A Primary Observation on Palynofacies of the Chuangde Section (Late Jurassic-Cretaceous), Gya
non-orthogonalmultipleaccess（noma）for
Non-Orthogonal Multiple Access (NOMA) for Indoor Visible Light CommunicationsRefik Caglar Kizilirmak Corbett Ray Rowell Dept. of Electrical and Electronics EngineeringNazarbayev UniversityAstana, Kazakhstanrefik.kizilirrn a********.kz,*********************.kz Abstract-Providing multiple access support to visible light communication (VLC) systems requires new networking architectures. Non-orthogonal multiple access (NOMA) is a proposed multiple access technique for future cellular systems. In this work, based on a realistic indoor channel conditions, we apply NOMA to indoor VLC channels and demonstrate its superior performance over orthogonal frequency division multiple access (OFDMA).Index Terms-visible light communication, OFDMA, NOMA, successive interference cancellationI. INTRODUCTIONVisible light communications (VLC) has recently received considerable attention as an alternative to wireless access technologies operating in radio frequency bands. VLC uses unlicensed spectrum, avoids the health concerns associated with electromagnetic radiation in the microwave bands, and achieves high data rates [1]. Although most of the recent advances in the field consider point-to-point transmission, networking with multiple access (MA) support for VLC is essential to provide multi-user wireless services such as Internet access in an office environment.Most of the MA techniques in radio and optical engineering can be applied to indoor VLC channels. For instance, well known cellular MA techniques such as time division multiple access (TDMA), frequency division multiple access (FDMA), or code division multiple access (CDMA) together with some optical MA techniques such as wavelength division multiple access (WDMA) and space division multiple access (SDMA) have already been proposed for visible light communications [2].NOMA is fundamentally different than other multiple access schemes which provide orthogonal access to the users eitherin time, frequency, code, or space. In NOMA, each user operates in the same band and at the same time where they are distinguished by their power levels. NOMA uses superposition coding [3][4] at the transmitter such that the successive interference cancellation (SIC) receiver can separate the users bothin the uplink and downlink channels. NOMA was originally proposed as a candidate radio access technology for 5G cellular systems [4]. Although the practical implementation of NOMA in 5G cellular networks is still under discussion, it can be readily employed by VLC systems. First, the SIC receiver978-1-4673-7726-3/15/$31.00 ©20151EEE 98Murat UysalDept. of Electrical and Electronics EngineeringOzyegin UniversityIstanbul, Turkey***********************.trperforms better with fewer users; this is usually the case for VLC, but not for cellular networks. Secondly, superposition coding requires the channel knowledge for each user in order to adjust the power split between them; in VLC, unlike cellular networks, user terminals are usually stable and the channel is deterministic. VLC network characteristics perfectly match with the requirements for a successful NOMA implementation. In this work, we propose the use of NOMA in a VLC downlink channel with a two-user scenario and compare its performance with OFDMA based VLC networks. DC biased optical OFDM (DCO-OFDM) [5] is used for both NOMA and OFDMA as it is most commonly used bipolar-to-unipolar conversion technique in optical OFDM systems. A concurrent study in [6] also discusses application of NOMA to VLC systems. Our work is different from [6] in two major aspects: First, we consider optical OFDM transmission and compare the achievable capacities of NOMA and OFDMA and second, we include the impact of cancellation error in SIC receiver and analyzed for VLC systems with further comparison of NOMA and OFDMA systems.The paper is organized as follows: Section 2 introduces the channel models for two user scenario. Section 3 presents DCO-OFDM based NOMA and OFDMA. Section 4 presents the results of the numerical studies, and finally, Section 5 concludes the paper.II. INDOOR CHANNEL MODELThe room is modeled as an indoor office space with dimensions 5x5x3meters (Fig. 1) where two user equipments (VEs) are sharing the common downlink channel.In order to obtain the channel impulse responses, the methodology described in [7] is followed based on ray tracing simulations using Zemax@ [8]. The reflection coefficients of the walls, ceiling, floor and desk surface are taken as 0.8, 0.8, 0.3 and 0.8, respectively. When the location of the center of the ground is set at (0,0,0), the locations of the light source, VEl and VE2 are respectively chosen as (0,0,3), (0, 0, 0.7) and (1.7, 1.9, 0.7). Fig. 2 presents the obtained channel impulse responses hI (t) and h2(t) for UEI and UE2, respectively. The electrical channel DC gains are then calculated as GI I hI(t)dt -52 dB and GI I hI(t)dt -58 dB respectively for VEl and VE2.h y2.5 m i, .' ............ _-t ........__ , ". G : : •••• 2 :G : •..• : ' : ..... . , . Sm , OFDMA 1 1 UEI UE2 conjugate I ( NOMA1 . 1 conjugate I .... symmetric ----. 1 I � Bandwidth ---- 1 1 Fig. 1. Room with two users sharing the common downlink channel. 4.5 .5 � 2.5 1.5 0.5-6 xlOtime (nsec)(a) � 0.8� 0.60.402 -6 xlOtime (nsec) (b)Fig. 2. Channel impulse responses with respect to 1 watt transmitted optical power for (a) VEl (b) VE2. III. SYSTEM MODELNOMA and conventional OFDMA are illustrated conceptually in Fig. I where in OFDMA, the two users share thedifferent parts of the bandwidth whereas NOMA utilizes allthe band for each user. In this section, we first present NOMA,then discuss OFDMA as a benchmark.A. NOMA with DCO-OFDM Fig. 3 shows the block diagram of DCO-OFDM basedNOMA system in downlink. The NOMA transmitter processesthe information of both users in parallel and obtains OFDMsignals Xl(t) and X 2(t) for VEl and VE2. In DCO-OFDM,the complex symbols s (PSK, QAM etc.) are first assignedto a subcarrier vector. The OFDM time domain signal isthen obtained by IFFT operation. One important constraintin IMIDD optical communication is that the waveform whichmodulates the LEDs should be real-valued and non-negative.It is known that when the complex subcarrier vector X satisfiesthe Hermitian symmetry property, the time signal at the output IFFT becomes real [9]. Hermitian symmetry can be imposedby constructing X as 99where N is the number of subcarriers. As seen in (1), obtaining a real-valued Xl(t) and X 2(t)sacrifices approximately half of the spectral efficiency for each user. The transmitter then applies superposition coding and forms the transmitted waveform as [3][4] where P is the total available power for the transmitted signal and Kn is the power splitting factor which defines the power levels to be allocated to each information signal. In (2), lE[lxl(t)12] and IE[lXl(t)l 2] are normalized to one. It is also possible to apply superposition coding first and then apply IFFT Finally, the DC biased signal x N (t) modulates the luminary which consists of L number of LED chips. The electrical signal at the receiver of VE k , k E 1, 2, can then be written as LI'JPL hk(t)Q9x(t) + nk(t) (3) i=l L I'L hk(t) (t) + Kn )X 2(t)] i=l2015 4th International Workshop on Optical Wireless Communications (I W OW)2010o 10 15 20Rate of user 2 (Mbps)25 30 35Fig. 5. Boundary of rate pairs (Mbps) for NOMA and OFDMA. Perfect interference cancellation is assumed for NOMA.2010o 10 15 20Rate of user 2 (Mbps)25 30 35Fig. 6. Boundary of rate pairs (Mbps) for NOMA and OFDMA. Imperfect interference cancellation is assumed for NOMA.V. CONCLUSIONIn this work, NOMA has been proposed and analyzed for indoor VLC downlink channels. For a realistic indoor channel model with illumination design constraints, the superior performance of NOMA over conventional OFDMA scheme has been demonstrated. Although, the receiver complexity can be seen as a drawback for NOMA, the return is considerable. Future work includes developing power allocation mechanism for higher number of users and building a prototype.ACKNOWLEDGEMENTWe would like to thank Mr. Farshad Miramirkhani for his kind assistance in preparation of Fig. 2 in Section 2.REFERENCES[1] T. Komine, M. Nakagawa,"Fundamental analysis for visible-light communication system using LED lightings", IEEE Trans. on Comsun.Electron.,vol. 50, pp. 100-107, 2004.[2] H. Elgala, R. Mesleh, H. Haas, "Indoor optical wireless communication:potential and state-of-the-art",IEEE Communications Magazine, vol. 49, no: 9, pp. 56-62, 2011.[3] Y. Saito,et. ai, "System level performance evaluation of downlinknonorthogonal multiple access (NOMA)," in Proc. IEEE Symposium on Personal, Indoor and Mobile Radio Communications (PlMRC), Sept.2013.[4] Y. Saito, et, ai, "Non-orthogonal multiple access (NOMA) for future radioaccess," in Proc. IEEE Vehiccular Technology Conference (VTC Spring), pp. 1-5, Sept. 2013.[5] J. Armstrong, "OFDM for optical communications", Journal of LightwaveTech., vo1.27, no.3, pp. 189-204, Feb., 2009.[6] H. Marshoud, V. M. Kapinas, G. K. Karaganniadis, S. Muhadiat,"Non-orthogonal multiple access for visible light communications,"lpdf/1504.oo934.pdf.[7] E. Sarbazi, M. Uysal, M. Abdallah and K.Qaraqe, "Indoor channelmodeling and characterization for visible light communications", 16th International Conference on Transparent Optical Networks (ICTON), July 2014.[8] [9] R. Mesleh, H. Elgala, and H. Haas, "On the performance of differentOFDM based optical wireless communication systems", J. Opt. Commun.Netw., vol. 3, no. 8, pp. 620-628, 2011.[10] J. Grubor, S. Randel, K-D. Langer, and J. W. Walewski, "Broadbandinformation broadcasting using LED-based interior lighting", J. of Lightwave Tech., vol. 26, no. 24, pp. 3883-3892, 2008.[11] J. G. Andrews, and T. H. Meng, "Optimum Power Control for SuccessiveInterference Cancellation With Imperfect Channel Estimation", IEEE Trans. on Wireless Comm., vol. 2, no. 2, pp. 375-383, 2003.[12] D. Tse and P. Vishwanathan, "Multiuser capacity and opportunisticcommunication," Fundamentals of Wireless Communication, 2005. [13] S. A. Colak, R.C. Kizilirmak, M. Uysal, "On the Performance ofDCO-OFDM Visible Light Communication Systems under illumination Constraints", in Proc. Int'1. Con! on Transparent Optical Networks (ICTON), pp.I-4, 2015.[14] Cree XLamp XP-E2 LEDs, datasheet.[15] M Rahaim, A Miravakili, T Borogovac, IDC Little, V Joyner, "Demonstration of a software Defined Visible Light Communication System," in Proc. the 17th Annual International Conference on Mobile Computing and Networking, Mobicom20 11.[16] I. Stefan, H. Burchardt, and H. Haas, "Area spectral efficiency performance comparison between VLC and RF femtocell networks," in Proc.IEEE Inti Con! on Commun. (ICC) , pp. 3825-3829, 2013.101。
孢粉相_原理及方法
古生物学报,44(1):138-156(2005年1月)Acta Palaeont ol ogica Sinica,44(1):138-156(Jan .,2005) 收稿日期:20042062103中国科学院留学基金和国家自然科学基金委特殊学科点基金资助。
孢粉相:原理及方法3李建国1) David J Batten2)1)中国科学院南京地质古生物研究所,南京210008;2)University of W ales,Aberyst w yth SY233DB,University of Manchester,ManchesterM139P L,UK 提要 介绍并评论孢粉相分析的原理和方法。
孢粉相从提出至今已经历了很长时间的发展,现已基本成熟。
尽管如此,它对大多数孢粉学家(包括中国学者)来说仍然是陌生的。
文中论述了进行成功的孢粉相研究的基础:孢粉有机质分类、术语及研究方法,包括采样、实验技术、数据采集和相识别的数学方法、古环境解释及能源潜力评价等方面。
与传统的只注重孢型的孢粉学相比,孢粉相强调对样品中的所有沉积有机质进行总体评价,从而可以帮助人们从沉积物中获得更多的信息,更清晰地重建和描绘盆地沉积图景并评价目的地层的能源潜力。
有机地球化学和煤岩学的一些研究内容和方向与孢粉相研究非常相似,文中对它们相关的研究也作了简评。
它们对孢粉相研究的影响主要体现在有机质分类和术语上,一些孢粉相研究者完全采用有机地球化学或煤岩学的。
但是,这些学科在研究目的、实验技术及数据采集方法等方面都存在差异,孢粉有机质及其分类不一定对等于特定的干酪根型或煤岩显微组分,同时一个孢粉相也不一定等同于一个干酪根组合或有机质相。
因此,孢粉相应该有独立的沉积有机质分类方案和术语系统。
但是,研究方法和分类等方面的不同,并不会妨碍孢粉相获得与有机地化、煤岩学研究相似的结果。
如果能够将孢粉相数据与其它方法的数据结合起来解释,可能会获得更加理想的、经受得住时间考验的结果。
2023-2024学年上海市静安区高三上学期期末教学质量调研考试英语试题
2023-2024学年上海市静安区高三上学期期末教学质量调研考试英语试题Directions: After reading the passage below, fill in the blanks to make the passages coherent and grammatically correct. For the blanks with a given word, fill in each blank with the proper form of the given word; for the other blanks, use one word that best fits each blank.Japan’s robot revolution in senior careJapan’s artificial intelligence expertise is transforming the elder care industry, with 1 (specialize) robotic care accomplishing more than just taking pressure off the critical shortage of caregivers. Senior care facilities across Japan are testing out such new robots 2 deliver a collection of social and physical health care and the government-backed initiative has been met with positive reviews by elderly residents.The rapidly graying population 3 (eye) by the government as a potential market for medical technology now. Disappointing government predictions show that by 2025, Japan's first baby boomers will have turned 75 and about 7 million people are likely to suffer from some form of dementia (痴呆). The nation won't be able to avoid a dementia crisis 4 an additional 380,000 senior care workers.The long-standing shortage of professional care workers has encouraged the Japanese government 5 (simplify) procedures for foreign caregivers to be trained and certified. The current Technical Intern Training Program between Vietnam, the Philippines, and Indonesia, under 6 Economic Partnership Agreement, was extended to include nursing care as well as agriculture, fishery, and construction sectors.7 the government made efforts to increase the numbers of senior care workers, the target number of foreign graduates has still fallen flat, with the national caregiver examination proving a major obstacle to pass. The success rate for foreign students was a merely 106 students last year, 8 has slightly improved to 216 students this year. Another depressing reality is that 19 to 38 percent of foreign nurses who pass the exam opt to leave the industry and return home, 9 (cite) tough work conditions and long hours. Given the challenges, this is 10 the government believes care robots will be able to step in.Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.A. smoothingB. remainC. switchedD. likelihoodE. impactF. tipG. broadly H. headed I. booming J. positioning K. reliablySea-level rise predictionsA team of University of Idaho scientists is studying a fast-moving glacier in Alaska in hopes of developing better predictions on how quickly global sea levels will rise.Tim Bartholomaus, a professor in the Department of Geography and Geological Sciences, spent several weeks on Turner Glacier in Alaska’s southeastern 11 near Disenchantment Bay. The glacier is unique because, unlike other glaciers, it rises greatly every five to eight years.A surging glacier is defined, 12 , as one that starts flowing at least 10 times faster than normal. But the how and why of that glacial movement is poorly understood, although recent research suggests that global climate change increases the 13 of glacial surging.During Turner’s surges, the mass of ice and rock will increase its speed from roughly 3 feet a day to 65 feet per day.All of that is important because glaciers falling into the ocean are a major contributor to sea level rise, and current clima te change models don’t 14 account for these movements. For example, Greenland’s glaciers are one of the leading contributors to global sea-level rise. Since the early 2000s, Greenland 15 from not having any effect on world sea levels, to increasing sea level by about 1 millimeter per year. Half of that yearly increase is due to warmer average temperatures, which leads to more ice melting. The other half, however, is because glaciers in Greenland are, as a whole, moving faster and running into the ocean more frequently.Glacial movement has something to do with water running underneath the glacier. Glaciers are full of holes, and water runs through those holes. When the water pressure is high underneath a glacier, it starts to move, partly because it’s li fting the mass of ice and rock off the ground and partly because it’s 16 the underside of the glacier.But how exactly does that water move through the glacier, and how does the movement 17 the glacier’s speed? Those are the questions the scientists ho pe to answer.Bartholomaus, some graduate students and researchers from Boise State University, 18 onto the ice in August. They set up a base camp at the toe of the glacier and spent their days flying in on helicopters. They placed roughly 30 instruments, burying them deeply into the glacier and 19 them on rock outcroppings (露岩) alongside the glacier. This summer the team will return to get the instruments and replace batteries. Those instruments will 20 on and around the glacier until the glacier surge stops, providing researchers with before and after data.Investors probably expect that following the suggestions of stock analysts would make them better off than doing the exact opposite. _________, recent research by Nicola Gennaioli and his colleagues shows that the best way to gain excess return s would be to invest in the shares least favored by analysts. They compute that, during the last 35 years, investing in the 10 percent of U. S. stocks analysts were most _________ about would have yielded on average 3 percent a year._________, investing in the 10 percent of stocks analysts were most pessimistic about would have yielded a surprising 15 percent a year.Gennaioli and colleagues shed light on this _________ with the help of cognitive sciences and, in particular, using Kahneman and Tversky's concept of representativeness. Decision makers, according to this view, _________ the representative features of a group or a phenomenon. These are defined as the features that occur more frequently in that group than in a baseline reference group.After observing strong earnings growth—the explanation goes—analysts think that the firm may be the next Google. “Googles” are in fact more frequent among firms experiencing strong growth, which makes them _________. The problem is that “Googles” are very _________ in absolute terms. As a result, expectations become too optimistic, and future performance_________. A model of stock prices in which investor beliefs follow this logic can account both qualitatively and quantitatively for the beliefs of analysts and the dynamics (动态变化) of stock returns.In related work, the authors also show that the same model can _________ booms and busts in the volume of credit and interest rate spreads.These works are part of a research project aimed at taking insights from cognitive sciences and at__________them into economic models. Kahneman and Tversky's concept of “representativeness” lies at the heart of this effort. “In a classical example, we __________ to think of Irishmen as redheads because red hair is much more frequent among Irishmen than among the rest of the world,” Prof. Gennaioli says. “However, only 10 percent of Irishmen are redheads. In our work, we develop models of belief formation that show this logic and study the __________ of this important psychological force in different fields.”Representativeness helps describe __________ and behavior in different fields, not only in financial markets. One such field is the formation of stereotypes about social groups. In a recent experimental paper, Gennaioli and colleagues show that representativeness can explain self-confidence, and in particular the __________ of women to compete in traditionally male subjects, such as mathematics.A slight prevalence of __________ male math ability in the data is enough to make math ability un-representative for women, driving their under confidence in this particular subject.21.A．Consequently B．Furthermore C．Nevertheless D．Meanwhile22.A．curious B．controversial C．concerned D．optimistic23.A．In brief B．By contrast C．In addition D．Without doubt 24.A．engagement B．concentration C．puzzle D．definition25.A．memorize B．prioritize C．modernize D．fertilize26.A．representative B．argumentative C．executive D．sensitive27.A．harsh B．adaptable C．crucial D．rare28.A．cheers B．disappoints C．stabilizes D．improves29.A．account for B．count on C．suffer from D．hold up30.A．pouring B．admitting C．integrating D．tempting31.A．pretend B．afford C．offer D．tend32.A．effects B．delights C．intervals D．codes33.A．companions B．scales C．expectations D．findings34.A．necessity B．involvement C．perseverance D．reluctance35.A．equivalent B．exceptional C．mysterious D．distressing Montessori was born in Italy in 1870 with progressive parents, who frequently communicated with the country’s leading thinkers and scholars. This enlightened family environment provided Montessori with many advantages over other young girls of the time.Her mother’s support was vital for some impo rtant decisions, such as her enrolment in a technical school after her elementary education. Her parents’ support also proved to be essential for her decision to study medicine, a field that was dominated by men.Soon after graduating, in 1896, Montessori began work as a voluntary assistant in a clinic at the University of Rome, where she cared for children with learning difficulties. The rooms were bare, with just a few pieces of furniture. One day, she found that the children were enthusiastically playing with breadcrumbs (面包屑) that had dropped on the floor. It then occurred to her that the origin of some intellectual disabilities could be related with poverty. With the right learning materials, these and other young minds could be nurtured, Montessori concluded.The observation would lead Montessori to develop a new method of education that focused on providing optimal stimulation during the sensitive periods of childhood.At its centre was the principle that all the learning materials should be child-sized and designed to appeal to all the senses. In addition, each child should also be allowed to move and act freely, and use their creativity and problem-solving skills. Teachers took the role of guides, supporting the children without press or control.Mont essori opened her first Children’s House in 1907. When the Fascists (法西斯主义者) first came into power in Italy in 1922, they initially embraced her movement. But they soon came to oppose the emphasis on the children’s freedom of expression. Montessori’s value s had always been about human respect, and the rights of children and women, but the Fascists wanted to use her work and her fame.Things reached a breaking point when the Fascist tried to influence the schools’ educational content, and in 1934 Montessori and her son decided to leave Italy. She didn’t return to her homeland until 1947, and she continued to write about and develop her method until her death in 1952, at the age of 81.36. The primary reason for Montessori to develop a new educational method was ______.A．her family’s supportive influence on her educationB．her experience as a voluntary assistant in a clinicC．her observation of children playing with breadcrumbs happilyD．her decision to study medicine, a field dominated by men37. What was a central principle of Montessori’s educational method as described in the passage?A．Providing standardized, one-size-fits-all learning materials.B．Encouraging strict discipline and control over children’s actions.C．Focusing on rote memorization and competition.D．Creating a free and children-centered learning environment.38. Montessori decided to leave Italy in 1934 because .A．she wanted to explore other countries and culturesB．she wanted to avoid the Fascist’s influence on her workC．she was offered a better job in a different countryD．she wanted to retire and enjoy a peaceful life in another country39. Which of the following words can best describe Montessori in this passage?A．Observant and innovative. B．Traditional and emotional.C．Progressive and dependent. D．Open-minded and indifferent. Reducing the workweek to four days could have a climate benefit. In addition to improving the well-being of workers, cutting working hours may reduce carbon emissions. But those benefits would depend on a number of factors, experts emphasize, including how people choose to spend nonworking time.Commuting and travelTransportation is the biggest contributor to greenhouse emissions. A November 2021 survey of2,000 employees and 500 business leaders in the United Kingdom found that if all organizations introduced a four-day week, the reduced trips to work would decrease travel overall by more than 691 million miles a week.But the climate benefits of less commuting could be eliminated, experts said, if people choose to spend their extra time off traveling, particularly if they do so by car or plane.Energy usageShorter working hours could lead to reductions in energy usage, experts said. According to a 2006 paper, if the United States adopted European work standards, the country would consume about 20 percent less energy.Energy could also be conserved if fewer resources are needed to heat and cool large office buildings, reducing demands on electricity. For example, if an entire workplace shuts down on the fifth day, that would help lower consumption — less so if the office stays open to accommodate employees taking different days off.Lifestyle changesIt’s possible that fewer working hours may lead some people to have a larger carbon footprint, bu t experts say research suggests that most people are likely to shift toward more sustainable lifestyles.One theory is that people who work more and have less free time tend to do things in more carbon-intensive ways, such as choosing faster modes of transportation or buying prepared foods. Convenience is often carbon-intensive and people tend to choose convenience when they're time-stressed. Meanwhile, some research suggests that those who work less are more likely to engage in traditionally low-carbon activities, such as spending time with family or sleeping.“When we talk about the four-day workweek and the environment, we focus on the tangible, but actually, in a way, the biggest potential benefit here is in the intangible,” experts said.40. What is identified as the leading cause of greenhouse emissions according to the passage?A．The well-being of employees.B．The conservation of energy.C．Commuting and travel.D．The European work standard.41. What can be inferred from the underlined sentence “the biggest potential benefit here is in the intangible” in the last paragraph?A．People will have big potential in achieving intangible benefits while working.B．People are more likely to engage in carbon-intensive activities due to time constraints.C．People may shift toward more sustainable lifestyles and lower carbon footprints.D．People may travel more frequently by car or plane during their extra time off.42. The passage is mainly written to .A．highlight the importance of shortening working time in the context of well-beingB．provide an overview of transportation emissions worldwideC．analyze the impact of reduced working hours on mode of businessD．illustrate factors affecting the climate benefits of a shorter workweekThe cultivation of plants by ants is more widespread than previously realized, and has evolved on at least 15 separate occasions.There are more than 200 species of ant in the Americas that farm fungi (真菌) for food, but this trait evolved just once sometime between 45 million and 65 million years ago. Biologists regard the cultivation of fungi by ants as true agriculture appearing earlier than human agriculture because it meets four criteria: the ants plant the fungus, care for it, harvest it and depend on it for food.By contrast, while thousands of ant species are known to have a wide variety of interdependent relationships with plants, none were regarded as true agriculture. But in 2016, Guillaume Chomicki and Susanne Renner at the University of Munich, Germany, discovered that an ant in Fungi cultivates several plants in a way that meets the four criteria for true agriculture.The ants collect the seeds of the plants and place them in cracks in the bark of trees. As the plants grow, they form hollow structures called domain that the ants nest in. The ants defecate (排便) at designated absorptive places in these domain, providing nutrients for the plant. In return, as well as shelter, the plant provides food in the form of fruit juice.This discovery prompted Chomicki and others to review the literature on ant-plant relationships to see if there are other examples of plant cultivation that have been overlooked. “They have never really been looked at in the framework of agriculture,” says Chomicki, who is now at the University of Sheffield in the UK. “It’s definitely widespread.”The team identified 37 examples of tree-living ants that cultivate plants that grow on trees, known as epiphytes (附生植物). By looking at the family trees of the ant species, the team was able to determine on how many occasions plant cultivation evolved and roughly when. Fifteen is a conservative estimate, says Campbell. All the systems evolved relatively recently, around 1million to 3 million years ago, she says.Whether the 37 examples of plant cultivation identified by the team count as true agriculture depends on the definitions used. Not all of the species get food from the plants, but they do rely on them for shelter, which is crucial for ants living in trees, says Campbell. So the team thinks the definition of true agriculture should include shelter as well as food.43. According to biologists, why is ant-fungus cultivation considered as a form of true agriculture?A．Because it occurred earlier than human agriculture.B．Because it fulfills the standards typical of agricultural practices.C．Because it redefines the four criteria for true human agriculture.D．Because it is less common than previously thought.44. What motivated Chomicki and others to review the literature on ant-plant relationships?A．They determined on new family trees of the ant species.B．They overlooked some tree-living ants that provided nutrients for the plants.C．They never studied the ant-plant relationships within the context of agriculture.D．They never identified any an t species that engaged in cultivation of fungi.45. Which of the following statements is supported by the team's findings according to the passage?A．Ants’ cultivation of plants is limited to a few specific species.B．The cultivation of fungi by ants is considered the earliest form of agriculture.C．True agriculture in ants involves only food-related interactions with plants.D．Ants have independently cultivated plants on at least 15 distinct occasions.46. What is the passage mainly about?A．The evolution of ants in the plant kingdom.B．The widespread occurrence of ant-plant cultivation.C．The discovery of a new ant species engaging in agriculture.D．The contrast between ant agriculture and human agriculture.What is the likelihood of you having someone who looks just like you? Would it be a good thing? And if you did have one, would you want to meet them?Consider how often your facial features are used to identify you. Your passport, ID card and driving license all feature your face. 47 You may need your face to unlock your smartphone and possibly even need it to exclude you from being present at a crime scene.The word “doppelgänger” refers to a person who looks the same as you, essentially sharing your features; those that you thought were unique to you and your identity. Not identical twins, as a doppelgänger has no relation to you. The idea originated in German folklore. 48So, let's get real. What are the chances of you having one in the first place? There's said to be a one in 135 chance of an exact match for you existing anywhere in the world, so the chances are pretty low, despite folk wisdom promising you otherwise. And the chances of meeting? The mathematical certainty of finding this particular person is supposedly less than one in a trillion.That said, these statistics may be a good thing. Historically, having a double wasn't always a positive. Back in 1999, an innocent American man, indistinguishable from the real criminal, was sent to prison for robbery, where he stayed for 19 years. 49 . In a different case, a woman in New York was accused of trying to poison her doppelgänger with deadly cheesecake so that she could steal her identity!50 The fascination with doppelgängers may be rooted in historical beliefs that facial resemblance meant they were from the same family or had a common ancestor. It leads to the hope that one day you will meet your lookalike, creating the thrill of a potentially strange meeting. However, as these encounters can be both interesting and disturbing, we understand that after such an experience, you might not want to meet your doppelgänger again.passage in no more than 60 words. Use your own words as far as possible.Competitive CheerleadingOver the years, cheerleading has taken two primary forms: game-time cheerleading and competitive cheerleading. Game-time cheerleaders’ main goal is to entertain the crowd and lead them with team cheers, which should not be considered a sport. However, competitive cheerleading is more than a form of entertainment. It is really a competitive sport.Competitive cheerleading includes lots of physical activity. The majority of the teams require a certain level of tumbling (翻腾运动) ability. It’s a very common thing for gymnasts, so it’s easy for them to go into competitive cheerleading. Usually these cheerleaders integrate lots of their gymnastics experience including their jumps, tumbling, and overall energy. They also perform lifts and throws.Competitive cheerleading is also an activity that is governed by rules under which a winner can be declared. It is awarded points for technique, creativity and sharpness. Usually the more difficult the action is, the better the score is. That’s why cheerleaders are trying to experience great difficulty in their performance. Besides, there is also a strict rule of time. The whole performance has to be completed in less than three minutes and fifteen seconds, during which the cheerleaders are required to stay within a certain area. Any performance beyond the limit of time is invalid.Another reason for the fact that competitive cheerleading is one of the hardest sports is that it has more reported injuries. According to some research, competitive cheerleading is the number one cause of serious sports injuries to women. Generally, these injuries affect all areas of the body, including wrists, shoulders, ankles, head, and neck.There can be no doubt that competitive cheerleading is a sport with professional skills. It should be noted that it is a team sport and even the smallest mistake made by one teammate can bring the score of the entire team down. So without working together to achieve the goal, first place is out of reach. ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ___________________________________________________________________________52. 如果不好好准备，周五的演讲可能会变得一塌糊涂。
OBSERVATION OF THE B c MESON AT CDF VAIA PAPADIMITRIOU for the CDF Collaboration
1 Introduction
+ The Bc meson is the lowest-mass bound state of quarkonium states containing a charm quark and a bottom anti-quark 1. Since this pseudoscalar ground state has non-zero avor, it has no strong or electromagnetic decay channels. It is the last such meson predicted by the Standard Model and the only meson with two di erent heavy quarks. It decays weakly yielding a large branching fraction to nal states containing a J= 2;3;4;5. Nonrelativistic potential models predict a Bc mass in the range 6.2{6.3 GeV/c2 6;7. In these models, the c and b are tightly bound in a very compact system and have a rich spectroscopy of excited states. The production of Bc mesons has been calculated in perturbative QCD. At transverse momenta pT large compared to the Bc mass the dominant process is that in which a b is produced by gluon fusion in the hard collision and fragmentation provides the c. At lower pT a full 4 calculation 8 shows that the dominant process is one in s which both the b and c quarks are produced in the hard scattering. These and other calculations 8;9;10;11;12 provide inclusive production cross sections along with distributions in pT and other kinematic variables. We expect three major contributions to the Bc decay width: b ! cW + with the c as a spectator, leading to nal states like J= or J= ` ; c ! sW + , with the b as spectator, leading to nal states like Bs or Bs ` ; and cb ! W + annihilation, leading to nal states like D K, or multiple pions. Since these processes lead to di erent nal states, their amplitudes do not interfere. When phase space and other e ects are included, the predicted lifetime is in the range 0.4{1.4 ps 2;13;14;15;16;17. Because of the wide range of predictions, a Bc lifetime measurement is a test of the di erent assumptions made in the various calculations. Several authors have also calculated the Bc partial widths to semileptonic nal states 2;3;4;5;18. Limits on the Bc production have been placed by
托福测试题及答案
托福测试题及答案一、听力理解（Listening Comprehension）1. What is the main topic of the lecture?A. The history of photographyB. The impact of technology on artC. The role of photography in journalismD. The evolution of camera technologyAnswer: B2. According to the professor, what is one of the benefits of digital photography?A. It allows for greater artistic control.B. It is less expensive than film photography.C. It is easier to manipulate images.D. It requires less technical skill.Answer: A3. Why does the professor mention the example of the painter who used a camera?A. To illustrate the limitations of photographyB. To show how technology can inspire traditional art formsC. To demonstrate the influence of photography on paintingD. To argue that photography is a form of artAnswer: B4. What does the student imply about the relationship between photography and journalism?A. They are becoming more distinct from each other.B. They have always been closely related.C. They are merging due to technological advancements.D. They are separate fields with little overlap.Answer: C二、阅读理解（Reading Comprehension）Passage 1: The Impact of Technology on Education5. What is the author's main argument in the passage?A. Technology has had a negative impact on education.B. The integration of technology in education is essentialfor its future.C. Technology has made education less personal.D. The benefits of technology in education are overstated. Answer: B6. According to the passage, which of the following is NOT a benefit of using technology in the classroom?A. Increased student engagementB. Access to a wider range of resourcesC. Improved test scoresD. Enhanced communication between students and teachers Answer: C7. The author cites the example of online courses toillustrate:A. The accessibility of education to a broader audience.B. The potential for personalized learning experiences.C. The challenges of maintaining student motivation.D. The need for traditional classroom settings.Answer: APassage 2: The History of Urban Planning8. What is the primary focus of the passage?A. The evolution of urban planning over time.B. The role of government in urban development.C. The impact of urban planning on society.D. The challenges faced by urban planners.Answer: A9. The author mentions ancient Rome to demonstrate:A. The early origins of urban planning.B. The influence of urban planning on architecture.C. The importance of public spaces in cities.D. The limitations of early urban planning techniques. Answer: A10. What does the passage suggest about modern urban planning?A. It is more focused on aesthetics than functionality.B. It has become more inclusive and sustainable.C. It is primarily driven by economic considerations.D. It has largely abandoned traditional planning principles.Answer: B三、口语表达（Speaking Expression）Task 1: Describe a memorable event from your childhood.Sample Response:One of the most memorable events from my childhood was the summer I spent at my grandparents' farm. I was about ten years old at the time. The experience was incredibly enriching as I learned about farming, the importance of hard work, and the beauty of nature. It was a time filled with laughter, new discoveries, and a deep connection with my family.Task 2: Explain why you think environmental conservation is important.Sample Response:Environmental conservation is crucial for several reasons. Firstly, it ensures the preservation of natural resources for future generations. Secondly, it helps maintain biodiversity, which is vital for the balance of ecosystems. Lastly, conservation efforts contribute to combating climate change by reducing pollution and promoting sustainable practices. It is our collective responsibility to protect the environment for the well-being of all living beings on Earth.四、写作任务（Writing Task）Task 1: Write an essay discussing the advantages and disadvantages of social media.Sample Essay:Social media has revolutionized the way we communicate and access information. On the positive side, it allows for instant connectivity with people around the world, fosters communities with shared interests, and provides a platform for self-expression and creativity. However, it also has its downsides, such as the spread of misinformation, the potential for cyberbullying, and the negative impact on mental health due to social comparison. Balancing the benefits and drawbacks is key to harnessing the power of social media responsibly.Task 2: Propose a solution to a local environmental issue in your community.Sample Essay:One pressing environmental issue in our community is the excessive use of single-use plastics. To address this, I propose the implementation of a local ordinance that bans single-use plastic items, such as straws and bags, and encourages the use of reusable alternatives. Additionally, educational campaigns can raise awareness about the environmental impact of plastic waste. By working together, our community can significantly reduce its。
Reading Comprehension
Practice Test #1 Reading Comprehension(18 Essays, 61 Questions)Essay #1. 019 (21201-!-item-!-188;#058&00019-00)During the nineteenth century, occupational information about women that was provided by the United States census--a population count conducted each decade--became more detailed and precise in response to social changes. Through 1840, simple enumeration by household mirrored a home-based agricultural economy and hierarchical social order: the head of the household (presumed male or absent) was specified by name, whereas other household members were only indicated by the total number of persons counted in various categories, including occupational categories. Like farms, most enterprises were family-run, so that the census measured economic activity as an attribute of the entire household, rather than of individuals.The 1850 census, partly responding to antislavery and women's rights movements, initiated the collection of specific information about each individual in a household. Not until 1870 was occupational information analyzed by gender: the census superintendent reported 1.8 million women employed outside the home in "gainful and reputable occupations." In addition, he arbitrarily attributed to each family one woman "keeping house." Overlap between the two groups was not calculated until 1890, when the rapid entry of women into the paid labor force and social issues arising from industrialization were causing women's advocates and women statisticians to press for more thorough and accurate accounting of women's occupations and wages.Question #1. 019-01 (21247-!-item-!-188;#058&000019-01)The primary purpose of the passage is to(A) explain and critique the methods used by early statisticians(B) compare and contrast a historical situation with a current-day one(C) describe and explain a historical change(D) discuss historical opposition to an established institution(E) trace the origin of a contemporary controversyQuestion #2. 019-02 (21293-!-item-!-188;#058&000019-02)Each of the following aspects of nineteenth-century United States censuses is mentioned in the passage EXCEPT the(A) year in which data on occupations began to be analyzed by gender(B) year in which specific information began to be collected on individuals in addition to the head of the household(C) year in which overlap between women employed outside the home and women keeping house was first calculated(D) way in which the 1890 census measured women's income levels and educational backgrounds(E) way in which household members were counted in the 1840 censusQuestion #3. 019-04 (21339-!-item-!-188;#058&000019-04)The passage suggests which of the following about the "women's advocates and women statisticians" mentioned in the highlighted text?(A) They wanted to call attention to the lack of pay for women who worked in the home.(B) They believed that previous census information was inadequate and did not reflect certaineconomic changes in the United States.(C) They had begun to press for changes in census-taking methods as part of their participation in the antislavery movement.(D) They thought that census statistics about women would be more accurate if more women were employed as census officials.(E) They had conducted independent studies that disputed the official statistics provided by previous United States censuses.Essay #2. 066 (21346-!-item-!-188;#058&00066-00)The general density dependence model can be applied to explain the founding of specialist firms (those attempting to serve a narrow target market). According to this model, specialist foundings hinge on the interplay between legitimation and competitive forces, both of which are functions of the density (total number) of firms in a particular specialist population. Legitimation occurs as a new type of firm moves from being viewed as unfamiliar to being viewed as a natural way to organize.At low density levels, each founding increases legitimation, reducing barriers to entry and easing subsequent foundings. Competition occurs because the resources that firms seek--customers, suppliers, and employees--are limited, but as long as density is low relative to plentiful resources, the addition of another firm has a negligible impact on the intensity of competition. At high density levels, however, competitive effects outweigh legitimation effects, discouraging foundings. The more numerous the competitors, the fiercer the competition will be and the smaller will be the incentive for new firms to enter the field.While several studies have found a significant correspondence between the density dependence model and actual patterns of foundings, other studies have found patterns not consistent with the model. A possible explanation for this inconsistency is that legitimation and competitive forces transcend national boundaries, while studies typically restrict their analysis to the national level. Thus a national-level analysis can understate the true legitimation and competitive forces as well as the number of foundings in an industry that is internationally integrated. Many industries are or are becoming international, and since media and information easily cross national borders, so should legitimation and its effects on overseas foundings. For example, if a type of firm becomes established in the United States, that information transcends borders, reduces uncertainties, and helps foundings of that type of firm in other countries. Even within national contexts, studies have found more support for the density dependence model when they employ broader geographic units of analysis--for example, finding that the model's operation is seen more clearly at the state and national levels than at city levels.Question #4. 066-02 (21392-!-item-!-188;#058&000066-02)According to the passage, which of the following may account for the inconsistency between the general density dependence model and the evidence provided by certain studies of foundings?(A) Such studies have overemphasized the impact of preexisting firms on the establishment of new firms.(B) Such studies have not focused strongly enough on the role of competition among newly established firms operating at the city and state levels.(C) Such studies fail to differentiate among specialist firms with regard to the degree to which they deviate from familiar forms of organization.(D) Such studies have not taken into account the fact that many industries are internationally integrated.(E) Such studies have neglected to investigate firms that attempt to serve only a narrow target market.Question #5. 066-04 (21438-!-item-!-188;#058&000066-04)In the second paragraph, the author is primarily concerned with(A) noting various exceptions to a certain general finding(B) examining the impact of one type of industry on another(C) proposing a possible explanation for an inconsistency(D) providing specific examples of a particular phenomenon(E) defending the validity of a particular study's conclusionsQuestion #6. 066-06 (21484-!-item-!-188;#058&000066-06)The passage suggests that when a population of specialist firms reaches a high density level, which of the following is likely to occur?(A) Foundings will decline despite legitimation that has occurred in these industries.(B) Increasing competition will encourage many firms to broaden their target market.(C) Competition for resources will become stabilized and thus foundings will be encouraged.(D) Many customers will abandon their loyalty to older firms as more innovative firms enter the market.(E) Firms will begin to cross national borders in an attempt to gain a competitive advantage. Question #7. 066-08 (21530-!-item-!-188;#058&000066-08)The primary purpose of the passage is to(A) question the validity of an economic model(B) point out some inconsistencies within an economic model(C) outline an economic model and suggest revisions to it(D) describe an economic model and provide specific examples to illustrate its use(E) explain why an economic model remains valid despite inconsistent research resultsEssay #3. 075 (21535-!-item-!-188;#058&00075-00)In its 1903 decision in the case of Lone Wolf v. Hitchcock, the United States Supreme Court rejected the efforts of three Native American tribes to prevent the opening of tribal lands to non-Indian settlement without tribal consent. In his study of the Lone Wolf case, Blue Clark properly emphasizes the Court's assertion of a virtually unlimited unilateral power of Congress (the House of Representatives and the Senate) over Native American affairs. But he fails to note the decision's more far-reaching impact: shortly after Lone Wolf, the federal government totally abandoned negotiation and execution of formal written agreements with Indian tribes as a prerequisite for the implementation of federal Indian policy. Many commentators believe that this change had already occurred in 1871 when--following a dispute between the House and the Senate over which chamber should enjoy primacy in Indian affairs--Congress abolished the making of treaties with Native American tribes. But in reality the federal government continued to negotiate formal tribal agreements past the turn of the century, treating these documents not as treaties with sovereign nations requiring ratification by the Senate but simply as legislation to be passed by both houses of Congress. The Lone Wolf decision ended this era of formal negotiation and finally did away with what had increasingly become the empty formality of obtaining tribal consent.Question #8. 075-03 (21581-!-item-!-188;#058&000075-03)According to the passage, the congressional action of 1871 had which of the following effects?(A) Native American tribal agreements were treated as legislation that had to be passed by both houses of Congress.(B) The number of formal agreements negotiated between the federal government and Native American tribes decreased.(C) The procedures for congressional approval and implementation of federal Indian policy were made more precise.(D) It became more difficult for Congress to exercise unilateral authority over Native American affairs.(E) The role of Congress in the ratification of treaties with sovereign nations was eventually undermined.Question #9. 075-06 (21627-!-item-!-188;#058&000075-06)According to the passage, which of the following resulted from the Lone Wolf decision?(A) The Supreme Court took on a greater role in Native American affairs.(B) Native American tribes lost their legal standing as sovereign nations in their dealings with the federal government, but their ownership of tribal lands was confirmed.(C) The federal government no longer needed to conclude a formal agreement with a Native American tribe in order to carry out policy decisions that affected the tribe.(D) The federal government began to appropriate tribal lands for distribution to non-Indian settlers.(E) Native American tribes were no longer able to challenge congressional actions by appealing to the Supreme Court.Question #10. 075-07 (21673-!-item-!-188;#058&000075-07)The author of the passage is primarily concerned with(A) identifying similarities in two different theories(B) evaluating a work of scholarship(C) analyzing the significance of a historical event(D) debunking a revisionist interpretation(E) exploring the relationship between law and social realityEssay #4. 094 (21680-!-item-!-188;#058&00094-00)Some historians contend that conditions in the United States during the Second World War gave rise to a dynamic wartime alliance between trade unions and the African American community, an alliance that advanced the cause of civil rights. They conclude that the postwar demise of this vital alliance constituted a lost opportunity for the civil rights movement that followed the war. Other scholars, however, have portrayed organized labor as defending all along the relatively privileged position of White workers relative to African American workers. Clearly, these two perspectives are not easily reconcilable, but the historical reality is not reducible to one or the other.Unions faced a choice between either maintaining the prewar status quo or promoting a more inclusive approach that sought for all members the right to participate in the internal affairs of unions, access to skilled and high-paying positions within the occupational hierarchy, and protection against management's arbitrary authority in the workplace. While union representatives often voiced this inclusive ideal, in practice unions far more often favored entrenched interests. The accelerating development of the civil rights movement following the Second World War exacerbated the unions'dilemma, forcing trade unionists to confront contradictions in their own practices.Question #11. 094-01 (21726-!-item-!-188;#058&000094-01)The "unions' dilemma" mentioned in the highlighted text can best be described as the question of whether or not to(A) pressure management to create more skilled and high-paying positions(B) fight for greater union participation in management decisions(C) include minority workers in their membership(D) extend full rights and benefits to all their members(E) emphasize the recruitment of new members over serving the needs of current members Question #12. 094-02 (21772-!-item-!-188;#058&000094-02)According to the passage, the historians mentioned in the first highlighted portion of text and the scholars mentioned in the second highlighted portion disagree about the(A) contribution made by organized labor to the war effort during the Second World War(B) issues that union members considered most important during the Second World War(C) relationship between unions and African Americans during the Second World War(D) effect of the Second World War on the influence of unions in the workplace(E) extent to which African Americans benefited from social and political changes following the Second World WarQuestion #13. 094-06 (21818-!-item-!-188;#058&000094-06)The passage is primarily concerned with(A) providing a context within which to evaluate opposing viewpoints about a historical phenomenon(B) identifying a flawed assumption underlying one interpretation of a historical phenomenon(C) assessing the merits and weaknesses of a controversial theory about a historical phenomenon(D) discussing the historical importance of the development of a wartime alliance(E) evaluating evidence used to support a particular interpretation of a historical phenomenonEssay #5. 118 (21825-!-item-!-188;#058&00118-00)Historians have identified two dominant currents in the Russian women's movement of the late tsarist period. "Bourgeois" feminism, so called by its more radical opponents, emphasized "individualist" feminist goals such as access to education, career opportunities, and legal equality. "Socialist" feminists, by contrast, emphasized class, rather than gender, as the principal source of women's inequality and oppression, and socialist revolution, not legal reform, as the only road to emancipation and equality.However, despite antagonism between bourgeois feminists and socialist feminists, the two movements shared certain underlying beliefs. Both regarded paid labor as the principal means by which women might attain emancipation: participation in the workplace and economic self-sufficiency, they believed, would make women socially useful and therefore deserving of equality with men. Both groups also recognized the enormous difficulties women faced when they combined paid labor with motherhood. In fact, at the First All-Russian Women's Congress in 1908, most participants advocated maternity insurance and paid maternity leave, although the intense hostility between some socialists and bourgeois feminists at the Congress made it difficult for them to recognize these areas ofagreement. Finally, socialist feminists and most bourgeois feminists concurred in subordinating women's emancipation to what they considered the more important goal of liberating the entire Russian population from political oppression, economic backwardness, and social injustice.Question #14. 118-03 (21871-!-item-!-188;#058&000118-03)The passage suggests that socialists within the Russian women's movement and most bourgeois feminists believed that in Russia(A) women would not achieve economic equality until they had political representation within the government(B) the achievement of larger political aims should take precedence over the achievement of women's rights(C) the emancipation of women would ultimately bring about the liberation of the entire Russian population from political oppression(D) women's oppression was more rooted in economic inequality than was the case in other countries(E) the women's movement was more ideologically divided than were women's movements in other countriesQuestion #15. 118-05 (21917-!-item-!-188;#058&000118-05)The passage is primarily concerned with(A) identifying points of agreement between two groups(B) advocating one approach to social reform over another(C) contrasting two approaches to solving a political problem(D) arguing that the views espoused by one political group were more radical than those espoused by another group(E) criticizing historians for overlooking similarities between the views espoused by two superficially dissimilar groupsQuestion #16. 118-06 (21963-!-item-!-188;#058&000118-06)According to the passage, Russian socialists within the women's movement and most bourgeois feminists disagreed about which of the following?(A) Whether legal reform was central to the achievement of feminist goals(B) Whether paid employment was important for the achievement of equality(C) Whether maternity insurance was desirable for working mothers(D) Whether working mothers faced obstacles(E) Whether women's emancipation should be subordinated to the liberation of the Russian population Essay #6. 145 (21972-!-item-!-188;#058&00145-00)Colonial historian David Allen's intensive study of five communities in seventeenth-century Massachusetts is a model of meticulous scholarship on the detailed microcosmic level, and is convincing up to a point. Allen suggests that much more coherence and direct continuity existed between English and colonial agricultural practices and administrative organization than other historians have suggested. However, he overstates his case with the declaration that he has proved "the remarkable extent to which diversity in New England local institutions was directly imitative of regional differences in the mother country."Such an assertion ignores critical differences between seventeenth-century England and New England. First, England was overcrowded and land-hungry; New England was sparsely populated andlabor-hungry. Second, England suffered the normal European rate of mortality; New England, especially in the first generation of English colonists, was virtually free from infectious diseases. Third, England had an all-embracing state church; in New England membership in a church was restricted to the elect. Fourth, a high proportion of English villagers lived under paternalistic resident squires; no such class existed in New England. By narrowing his focus to village institutions and ignoring these critical differences, which studies by Greven, Demos, and Lockridge have shown to be so important, Allen has created a somewhat distorted picture of reality.Allen's work is a rather extreme example of the "country community" school of seventeenth-century English history whose intemperate excesses in removing all national issues from the history of that period have been exposed by Professor Clive Holmes. What conclusion can be drawn, for example, from Allen's discovery that Puritan clergy who had come to the colonies from East Anglia wereone-third to one-half as likely to return to England by 1660 as were Puritan ministers from western and northern England? We are not told in what way, if at all, this discovery illuminates historical understanding. Studies of local history have enormously expanded our horizons, but it is a mistake for their authors to conclude that village institutions are all that mattered, simply because their functions are all that the records of village institutions reveal.Question #17. 145-03 (22018-!-item-!-188;#058&000145-03)According to the passage, which of the following was true of most villages in seventeenth-century England?(A) The resident squire had significant authority.(B) Church members were selected on the basis of their social status within the community.(C) Low population density restricted agricultural and economic growth.(D) There was little diversity in local institutions from one region to another.(E) National events had little impact on local customs and administrative organization.Question #18. 145-05 (22064-!-item-!-188;#058&000145-05)The passage suggests that Professor Clive Holmes would most likely agree with which of the following statements?(A) An understanding of seventeenth-century English local institutions requires a consideration of national issues.(B) The "country community" school of seventeenth-century English history distorts historical evidence in order to establish continuity between old and new institutions.(C) Most historians distort reality by focusing on national concerns to the exclusion of local concerns.(D) National issues are best understood from the perspective of those at the local level.(E) Local histories of seventeenth-century English villages have contributed little to the understanding of village life.Question #19. 145-07 (22110-!-item-!-188;#058&000145-07)It can be inferred from the passage that the author of the passage considers Allen's "discovery" (see highlighted text) to be(A) already known to earlier historians(B) based on a logical fallacy(C) improbable but nevertheless convincing(D) an unexplained, isolated fact(E) a new, insightful observationQuestion #20. 145-08 (22156-!-item-!-188;#058&000145-08)The author of the passage is primarily concerned with(A) substantiating a claim about a historical event(B) reconciling two opposing ideas about a historical era(C) disputing evidence a scholar uses to substantiate a claim about a historical event(D) analyzing two approaches to scholarly research and evaluating their methodologies(E) criticizing a particular study and the approach to historical scholarship it representsEssay #7. 146 (22165-!-item-!-188;#058&00146-00)The United States government has a long-standing policy of using federal funds to keep small business viable. The Small Business Act of 1953 authorized the Small Business Administration (SBA) to enter into contracts with government agencies having procurement powers and to arrange for fulfillment of these contracts by awarding subcontracts to small businesses. In the mid-1960's, during the war on poverty years, Congress hoped to encourage minority entrepreneurs by directing such funding to minority businesses. At first this funding was directed toward minority entrepreneurs with very low incomes. A 1967 amendment to the Economic Opportunity Act directed the SBA to pay special attention to minority-owned businesses located in urban or rural areas characterized by high proportions of unemployed or low-income individuals. Since then, the answer given to the fundamental question of who the recipients should be--the most economically disadvantaged or those with the best prospects for business success--has changed, and the social goals of the programs have shifted, resulting in policy changes.The first shift occurred during the early 1970's. While the goal of assisting the economically disadvantaged entrepreneur remained, a new goal emerged: to remedy the effects of past discrimination. In fact, in 1970 the SBA explicitly stated that their main goal was to increase the number of minority-owned businesses. At the time, minorities constituted seventeen percent of the nation's population, but only four percent of the nation's self-employed. This ownership gap was held to be the result of past discrimination. Increasing the number of minority-owned firms was seen as a way to remedy this problem. In that context, providing funding to minority entrepreneurs in middle- and high-income brackets seemed justified.In the late 1970's, the goals of minority-business funding programs shifted again. At the Minority Business Development Agency, for example, the goal of increasing numbers of minority-owned firms was supplanted by the goal of creating and assisting more minority-owned substantive firms with future growth potential. Assisting manufacturers or wholesalers became far more important than assisting small service businesses. Minority-business funding programs were now justified as instruments for economic development, particularly for creating jobs in minority communities of high unemployment.Question #21. 146-01 (22211-!-item-!-188;#058&000146-01)The primary purpose of the passage is to(A) discuss historical changes in a government policy(B) describe the role of Congress in regulating the work of the SBA(C) contrast types of funding sources used by minority businesses(D) correct a misconception about minority entrepreneurship(E) advocate an alternative approach to funding minority entrepreneursQuestion #22. 146-05 (22257-!-item-!-188;#058&000146-05)It can be inferred that the "ownership gap" (see highlighted text) would be narrowed if which of the following were to occur?(A) Minority entrepreneurs received a percentage of government contracts equal to that received by nonminority entrepreneurs.(B) Middle- and high-income minority entrepreneurs gave more assistance to their low-income counterparts in the business community.(C) Minority entrepreneurs hired a percentage of minority employees equal to the percentage of minority residents in their own communities.(D) The percentage of self-employed minority persons rose to more than ten percent of allself-employed persons.(E) Seventeen percent of all persons employed in small businesses were self-employed.Question #23. 146-06 (22303-!-item-!-188;#058&000146-06)According to the passage, in 1970 funding to minority entrepreneurs focused primarily on which of the following?(A) Alleviating chronic unemployment in urban areas(B) Narrowing the ownership gap(C) Assisting minority-owned businesses with growth potential(D) Awarding subcontracts to businesses that encouraged community development(E) Targeting the most economically disadvantaged minority-owned businessesQuestion #24. 146-09 (22349-!-item-!-188;#058&000146-09)Which of the following best describes the function of the second paragraph in the passage as a whole?(A) It narrows the scope of the topic introduced in the first paragraph.(B) It presents an example of the type of change discussed in the first paragraph.(C) It cites the most striking instance of historical change in a particular government policy.(D) It explains the rationale for the creation of the government agency whose operations are discussed in the first paragraph.(E) It presents the results of policies adopted by the federal government.Essay #8. 147 (22358-!-item-!-188;#058&00147-00)In terrestrial environments, gravity places special demands on the cardiovascular systems of animals. Gravitational pressure can cause blood to pool in the lower regions of the body, making it difficult to circulate blood to critical organs such as the brain. Terrestrial snakes, in particular, exhibit adaptations that aid in circulating blood against the force of gravity.The problem confronting terrestrial snakes is best illustrated by what happens to sea snakes when removed from their supportive medium. Because the vertical pressure gradients within the blood vessels are counteracted by similar pressure gradients in the surrounding water, the distribution of blood throughout the body of sea snakes remains about the same regardless of their orientation in space, provided they remain in the ocean. When removed from the water and tilted at various angles。
全国大学英语CET四级考试试卷及答案指导
全国大学英语CET四级考试自测试卷及答案指导一、写作（15分）CET-4 Writing SectionDirections: For this part, you are allowed 30 minutes to write a short essay on the topic given below. You should write at least 120 words but no more than 180 words.Topic:In recent years, there has been a growing trend of young people choosing to live a minimalist lifestyle. What is your opinion on this trend? Write an essay entitled “The Charm and Challenge of Minimalist Living” to discuss the reasons behind this trend and its impact on individuals and society. You can cite examples to support your point of view.Sample EssayThe Charm and Challenge of Minimalist LivingIn the fast-paced modern world, the concept of minimalist living has become increasingly popular among young adults, as they seek a simpler, more meaningful way of life. The essence of minimalism lies in owning fewer possessions, which allows for greater focus on personal growth and experiences rather than material goods. This shift towards simplicity not only brings about a sense of freedom from the burden of excess but also encourages a more environmentally friendlylifestyle.On an individual level, adopting a minimalist approach can lead to reduced stress and increased happiness. By decluttering their physical space, people often find that their mental space becomes clearer as well, enabling them to concentrate on what truly matters—such as relationships, health, andself-development. Furthermore, with less time and energy spent on managing and maintaining belongings, one can dedicate more resources to pursuing passions and interests, leading to a more fulfilling existence.From a societal perspective, the minimalist movement contributes positively by promoting sustainable consumption patterns. As more individuals choose to buy less and opt for quality over quantity, the overall demand for products decreases, potentially reducing waste and conserving natural resources. Moreover, it fosters a culture that values experiences and connections, moving away from the consumerist mindset that often defines success through accumulation of wealth and possessions.However, embracing minimalism does come with its challenges. It requires a significant change in mindset and habits, which can be difficult for some. Additionally, in societies where social status is frequently associated with visible signs of wealth, minimalists might face judgment or misunderstanding. Despite these obstacles, the benefits of a minimalist lifestyle, including enhanced well-being and a lighter ecological footprint, make it a compelling choice for many.In conclusion, while the path to minimalist living may present certain hurdles, the potential rewards for both individuals and the wider community are profound. By simplifying our lives, we not only enrich our own experiences but also contribute to a more sustainable and harmonious world.Analysis•Introduction: The opening paragraph introduces the concept of minimalist living, setting the stage for the discussion.•Body Paragraphs:•Individual Impact: Explains how minimalism can reduce stress, increase happiness, and allow for more focus on personal development.•Societal Impact: Discusses the positive effects on the environment and the promotion of a value system based on experiences and connections rather than material possessions.•Challenges: Acknowledges the difficulties in adopting a minimalist lifestyle, such as changing established mindsets and facing societal pressures.•Conclusion: Summarizes the key points and reiterates the overall positive impact of minimalist living, emphasizing the dual benefits for personal well-being and environmental sustainability.This sample essay demonstrates a clear structure, logical argumentation, and the use of specific examples to support the main ideas, all of which are essential components of a strong CET-4 writing piece.二、听力理解-短篇新闻（选择题，共7分）第一题News Item 1:A new study suggests that eating a high-protein diet can help people maintain muscle mass as they age. The study, published in the Journal of the American Medical Association, found that older adults who consumed more protein were less likely to experience muscle loss compared to those who consumed less protein. Researchers believe that the high protein intake is essential for muscle repair and maintenance, especially in the aging population.Questions:1、What is the main finding of the study?A) Older adults with a high-protein diet are more likely to experience muscle loss.B) A high-protein diet is not beneficial for muscle repair.C) High protein intake is essential for muscle repair and maintenance in older adults.D) The study was conducted on a small sample size.2、In which journal was the study published?A) The New England Journal of MedicineB) The Journal of the American Medical AssociationC) The British Medical JournalD) The Lancet3、What is the primary focus of the study?A) The effects of a low-carb diet on muscle massB) The impact of physical exercise on muscle repairC) The importance of high protein intake in older adultsD) The role of genetics in muscle lossAnswers:1、C2、B3、C第二题Listening Comprehension - News ReportNews Content:The United Nations announced today that it has launched a new initiative aimed at promoting literacy worldwide. The campaign, called “Read to Succeed,” aims to provide educational resources and support to communities where access to reading materials is limited. At the launch event in New York City, UN Secretary-General highlighted the importance of literacy in achieving sustainable development goals. He stated that “by empowering individuals with the ability to read and write, we are not only improving their lives but also contributing to the overall stability and prosperity of our world.”Questions:1、What is the name of the new initiative launched by the United Nations?A. Write for ChangeB. Read to SucceedC. Books for AllAnswer: B. Read to Succeed2、、Where was the launch event of the campaign held?A. GenevaB. ParisC. New York CityAnswer: C. New York City3、、According to the UN Secretary-General, what is one of the main goals of promoting literacy?A. To enhance global tradeB. To improve individual lives and contribute to world stability and prosperityC. To increase tourismAnswer: B. To improve individual lives and contribute to world stability and prosperity三、听力理解-长对话（选择题，共8分）第一题Part Three: Listening ComprehensionIn this section, you will hear several long conversations. At the end ofeach conversation, a few questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question, there will be a pause. During the pause, you must read the four choices marked A), B), C) and D), and decide which is the best answer. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.ConversationM: Hey, have you heard about the CET-4 exam? It’s only two weeks away.W: Yeah, I know. I’m so nervous. I’ve been preparing for it for months, but I still feel like I’m not ready.M: I feel the same way. It’s really tough, especially the listening section. Do you have any tips for improving our listening skills?W: Well, I th ink it’s important to practice regularly. You can listen to English news or watch English movies to get used to the accent.M: That’s a good idea. But what about the questions? They can be quite tricky sometimes.W: Yes, you’re right. It’s important to und erstand the main idea of the conversation and the details as well. I usually take notes while listening to make sure I don’t miss anything important.M: I’ll have to start taking notes too. By the way, what’s the format of the listening section?W: It consists of three parts. There are 20 questions in total. The first part is a short conversation, the second part is a long conversation, and thethird part is a passage.M: Oh, I see. I guess we better start practicing now.Questions1、What is the main topic of the conversation?A) Preparing for the CET-4 exam.B) Listening skills for the CET-4 exam.C) The format of the CET-4 exam.D) Tips for passing the CET-4 exam.2、What does the woman suggest to improve listening skills?A) Reading English newspapers.B) Listening to English songs.C) Watching English movies.D) Taking English courses.3、What does the woman say about the listening section?A) It’s the easiest part of the exam.B) It’s quite difficult.C) It’s not necessary to practice.D) It requires good note-taking skills.4、How many questions are there in the listening section?A) 10B) 15C) 20D) 25Answers1、A2、C3、B4、C第二题对话内容：W: Hey, Mark! I heard you’re planning a trip to Japan. When are you going?M: Hi, Lisa. Yeah, I’m really excited about it. I’m actually leaving next week. I’ve been saving up for this for quite some time.W: That’s great! How long will you be staying there? And where exactly are you going?M: I’ll be in Japan for two weeks. My first stop is Tokyo. I’m going to spend about fi ve days there and then head over to Kyoto. After that, I’m thinking of visiting Hiroshima before coming back to Tokyo for my flight home.W: Wow, sounds like an amazing itinerary. Are you going alone or with someone?M: I’m traveling by myself. I love the freedom of solo travel; it allows me to make spontaneous decisions and fully immerse myself in the culture. Plus, I can practice my Japanese more when I’m on my own.W: That’s true. Speaking of which, how’s your Japanese coming along? Iremember you were taking classes last year.M: It’s getting better, but I still have a lot to learn. I’m able to handle basic conversations now, so I hope that will help. I also downloaded a translation app just in case.W: Good idea. What are you most looking forward to on this trip?M: Oh, definitely trying all the different kinds of food. I’m a huge fan of Japanese cuisine, and I can’t wait to try authentic sushi, ramen, and tempura. But, I’m also very excited to visit historical sites and temples. There’s just something so peaceful about them.W: It sounds like you have a wonderful adventure ahead of you. I hope you have a fantastic time, Mark!M: Thanks, Lisa. I really appreciate it. I’ll make sure to bring back lots of photos and stories to share.问题：1、How long is Mark planning to stay in Japan?•A) One week•B) Two weeks•C) Three weeks•D) Four weeks•答案: B) Two weeks2、What is the first city Mark plans to visit in Japan?•A) Osaka•B) Kyoto•C) Tokyo•D) Hiroshima•答案: C) Tokyo3、Why does Mark prefer to travel alone?•A) He enjoys making spontaneous decisions.•B) He wants to save money.•C) He doesn’t have any friends who want to go.•D) He prefers to read books during his travels.•答案: A) He enjoys making spontaneous decisions.4、Which of the following is NOT something Mark is looking forward to on his trip?•A) Visiting historical sites•B) Trying different kinds of Japanese food•C) Going to the beach•D) Experiencing the peacefulness of temples•答案: C) Going to the beach四、听力理解-听力篇章（选择题，共20分）第一题听力篇章Passage OneIn the United States, there are many different ways to go to school. Somestudents go to public schools, while others go to private schools. Public schools are supported by the government, and all students can go to them. Private schools are supported by parents, and they charge tuition.The first grade in the United States is for children who are five years old. Children go to school from Monday to Friday, from 8:00 a.m. to 3:00 p.m. Each school day is divided into periods. During each period, students have different subjects to study, such as math, science, language arts, social studies, and physical education.In the United States, the education system emphasizes critical thinking and problem-solving skills. Teachers encourage students to ask questions and express their opinions. They also use a variety of teaching methods, such as group discussions, projects, and experiments, to help students learn.1、What are the two main types of schools in the United States?A. Public and private schoolsB. Online and offline schoolsC. Technical and vocational schoolsD. High and middle schools2、What is the age of children in the first grade?A. 5 years oldB. 6 years oldC. 7 years oldD. 8 years old3、What do American teachers emphasize in their teaching?A. Memorization and repetitionB. Critical thinking and problem-solving skillsC. Reading and writingD. Physical education答案：1、A2、A3、BSecond Part: Listening Comprehension - Listening PassagesDirections: In this section, you will hear one passage. At the end of each passage, you will hear three questions. After you hear a question, you must choose the best answer from the four choices marked A), B), C), and D). Then mark the corresponding letter on your Answer Sheet with a single line through the center.Passage OneAttention, please! Welcome to the Freshman Orientation at Greenleaf University. My name is Sarah, and I’ll be guiding you through today’s program. The orientation is designed to familiarize new students with campus facilities and services. Firstly, let me introduce our library—it’s open from 8 AM until midnight on weekdays and from noon until 8 PM on weekends. You can access online journals and databases using your student ID number. Next, we have the cafeteriawhich serves breakfast, lunch, and dinner; it also offers vegetarian options. Lastly, don’t forget to check out the sports center, where you can join various clubs like basketball or yoga. That concludes our introduction; now le t’s move on to the Q&A session.Questions 1-3 are based on the passage you have just heard.1、When does the library close on weekdays?A) At 8 PM.B) At midnight.C) At noon.D) At 8 AM.Answer: B) At midnight.2、What do new students need to use the online resources of the library?A) A library card.B) A student ID number.C) A password.D) A registration form.Answer: B) A student ID number.3、Which facility was NOT mentioned in the introduction?A) The cafeteria.B) The sports center.C) The bookstore.D) The library.Answer: C) The bookstore.This is a mock-up example designed for illustrative purposes. For actual CET practice materials, please refer to officially published study guides and previous years’ papers.第三题In this section, you will hear 1 passage. At the end of the passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A), B), C), and D). Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.Passage:The internet has become an indispensable part of our daily lives, and its influence extends far beyond our personal communications. One of the most significant impacts of the internet is on education. With the advent of online learning platforms, students can access a vast array of educational resources from around the world, at any time and from anywhere. This has revolutionized the traditional classroom setting and has opened up a new era in education.However, this shift to online education also brings along challenges. One of the primary concerns is the potential for decreased social interaction among students. In traditional classrooms, students have the opportunity to interact with their peers and learn from each other’s experiences. This social interaction is crucial for their overall development. Online learning, on theother hand, can sometimes isolate students, making it difficult for them to build meaningful relationships.Another challenge is the issue of academic integrity. With the ease of accessing information online, students may be tempted to plagiarize or use someone else’s work without proper attribution. This not only undermines their own learning but also hampers the educational process for others.Despite these challenges, the benefits of online education cannot be overlooked. It provides flexibility and convenience, allowing students to learn at their own pace and in their own time. Moreover, it encourages self-discipline and independence, as students must take responsibility for their own learning.Questions:1、What is the main impact of the internet on education according to the passage?A) Increased social interaction among studentsB) Enhanced access to educational resourcesC) Improved academic integrityD) Decreased reliance on traditional classroom settings2、What is one of the primary concerns regarding online education?A) The need for more structured learning environmentsB) The potential for decreased social interactionC) The difficulty of maintaining academic integrityD) The lack of flexibility and convenience3、According to the passage, what is a potential negative outcome of online education?A) Increased student engagement in social activitiesB) Improved academic performance due to better time managementC) Enhanced access to a diverse range of educational materialsD) Isolation of students and difficulty in building relationshipsAnswers:1、B2、B3、D五、阅读理解-词汇理解（填空题，共5分）第一题Read the following passage and fill in each blank with ONE word from the word bank. Each word may be used only ONCE.In today’s fast-paced world, communication skills are more important than ever. Effective communication not only helps us express our ideas clearly, but also fosters better relationships with others. Here are some tips to improve your communication skills:1、Communication is a two-way process. It involves not only speaking but also listening actively. When you listen actively, you are fully focused on the speaker and try to understand their perspective.2、Non-verbal communication plays a crucial role in how we interact with others. Our body language, facial expressions, and gestures can all convey messages. For example, a smile can make a conversation more pleasant, while a frown can create a negative impression.3、Being clear and concise is essential in communication. Avoid using jargon or technical terms that your audience may not understand. Instead, use simple language that everyone can easily follow.4、It’s important to be open and honest in your communication. This means being transparent about your thoughts and feelings, and being willing to listen to others’ opinions as well.5、Practice makes perfect. The more you communicate, the better you will become at it. Consider joining a group or attending a workshop to improve your skills.Word bank:a.fosterb. transparentc.cruciald.expresse. involvedNow fill in the blanks:1、Communication is a two-way process,___________speaking but also listening actively.2、Non-verbal communication plays a___________role in how we interact with others.3、Being clear and concise is essential in communication,___________using jargon or technical terms.4、It’s important to be open and honest in yourcommunication,___________being transparent about your thoughts and feelings.5、The more you communicate, the better you will become atit,___________joining a group or attending a workshop.第二题Reading Passage:Many people believe that a good marriage is one where the partners have many shared interests. However, research suggests that this is not always the case. In fact, studies have shown that couples who have different hobbies and interests tend to be happier and more satisfied with their relationships. This is because when partners have their own individual interests, they are less likely to become bored with each other and more likely to support each other in their endeavors.The following sentences are extracted from the passage above. Fill in each blank with one word from the passage. Choose the best answer to complete the sentence.1、In many people’s opinions, a good marriage is one where the partners__________many shared interests.2、Research suggests that couples who have__________hobbies and interests tend to be happier.3、When partners have their own individual interests, they are less likely to become__________with each other.4、Different hobbies and interests can help couples support each other in their __________.5、The passage implies that boredom in a marriage is often causedby__________shared interests.Answers:1、have2、different3、bored4、endeavors5、lacking六、阅读理解-长篇阅读（选择题，共10分）第一题Reading PassagesPassage OneGlobalization has brought both opportunities and challenges to individuals and societies. One of the most significant impacts of globalization is the increase in international trade and investment. This has led to the growth of multinational corporations (MNCs) and the integration of national economies into a global market. However, this process has also raised concerns about the impact on local cultures, labor rights, and environmental sustainability.Questions:1、What is the main topic of the passage?a) The benefits of globalizationb) The challenges of globalizationc) The role of MNCs in globalizationd) The impact of globalization on local cultures2、The passage mentions the growth of what as a result of globalization?a) Small local businessesb) Multinational corporationsc) National parksd) Agricultural production3、Which of the following is NOT mentioned as a concern related to globalization?a) The erosion of local culturesb) The exploitation of laborc) The decline in education standardsd) The degradation of the environment4、The passage suggests that globalization has led to:a) A decrease in international tradeb) A rise in national protectionismc) The integration of national economiesd) The isolation of local communities5、The author’s atti tude towards globalization can be described as:a) Favorableb) Criticalc) Indifferentd) AmbiguousAnswers:1、b) The challenges of globalization2、b) Multinational corporations3、c) The decline in education standards4、c) The integration of national economies5、b) Critical第二题Reading PassagesPassage OneIn the past few decades, the Internet has revolutionized the way we communicate, access information, and conduct business. This technological marvel has brought about both advantages and challenges. The following article explores some of the key impacts of the Internet on society.1.The Internet has significantly enhanced communication by allowing people to connect with each other across the globe. (T/F)2.The Internet has had a negative impact on traditional businesses, leading to their decline. (T/F)3.Access to information has become more difficult due to the vast amount of data available online. (T/F)Questions:1、What is the main topic of the first paragraph?A. The history of the InternetB. The advantages and challenges of the InternetC. The decline of traditional businessesD. The role of the Internet in global communication2、Which of the following is NOT mentioned as an impact of the Internet in the passage?A. Improved communicationB. Increased access to informationC. Negative impact on traditional educationD. Enhanced global business opportunities3、The author implies that the Internet has made it easier for people to:A. find jobs locallyB. access global marketsC. avoid communicating in personD. rely on traditional media4、The passage suggests that the Internet has had a significant effect on:A. the speed of global travelB. the availability of informationC. the number of people with televisionsD. the quality of local newspapers5、According to the passage, which of the following is a challenge associated with the Internet?A. Increased job opportunitiesB. Improved communicationC. The difficulty in finding accurate informationD. The growth of the global economyAnswers:1、B2、C3、B4、B5、C七、阅读理解-仔细阅读（选择题，共20分）第一题Read the following passage and answer the questions below it.The Internet has become an integral part of our daily lives, transforming the way we communicate, work, and entertain ourselves. With its vast resources and instant access to information, it has opened up new possibilities for learning and collaboration. However, the rapid growth of the Internet has also brought about numerous challenges, particularly in the realm of privacy and security.One of the most significant concerns is the potential for identity theft. Cybercriminals can exploit vulnerabilities in computer systems to stealpersonal information, such as credit card numbers, social security numbers, and bank account details. This information can then be used to make unauthorized purchases or withdrawals, causing financial and personal damage to the victim.Another issue is the spread of misinformation. With the ease of sharing information online, false or misleading content can quickly spread, influencing public opinion and causing confusion. This has become particularly evident during times of crisis, such as the COVID-19 pandemic, where false information has had serious consequences.Despite these challenges, the Internet continues to offer immense benefits. Here are some ways in which it has transformed various aspects of our lives:cation: Online learning platforms have made education more accessible to people worldwide. Students can now take courses from top universities without leaving their homes. This has democratized education and provided opportunities for lifelong learning.2.Business: The Internet has revolutionized the way businesses operate. E-commerce has become a multi-billion-dollar industry, allowing companies to reach customers globally. Additionally, cloud computing has made data storage and processing more efficient and cost-effective.3.Healthcare: Telemedicine has become increasingly popular, particularly during the pandemic. Patients can now consult with healthcare professionals remotely, saving time and resources. This has also helped to bridge the gap in healthcare services in remote areas.4.Social Interaction: Social media platforms have transformed the way we connect with others. People can now stay in touch with friends and family acrossthe globe, share experiences, and build communities of like-minded individuals.5.Entertainment: Streaming services have changed the way we consume entertainment. We can now watch movies, TV shows, and listen to music from anywhere at any time, making the world a more connected place.Questions:1、What is one of the major concerns associated with the rapid growth of the Internet?A) Limited access to informationB) Potential for identity theftC) Increase in the cost of online servicesD) Decrease in the quality of education2、How has the Internet affected the way we learn?A) It has made education more expensive.B) It has made education more accessible.C) It has made education less efficient.D) It has made education less secure.3、What is the main purpose of the passage?A) To highlight the negative aspects of the Internet.B) To discuss the benefits and challenges of the Internet.C) To promote the use of the Internet in education.D) To provide a comprehensive guide to online safety.4、Which of the following is NOT mentioned as a way the Internet has。
CAP Regulation 1-2 - Publications Management说明书
F REQUENTLY A SKED Q UESTIONS FORCAP R EGULATION 1-2–P UBLICATIONS M ANAGEMENT1.Do all current publications issued by regions and their subordinate units become invalid onNovember 7, 2016?It depends on the document:Policy letters and similar documents that direct requirements or establish proceduresare prohibited.Supplements and OIs to current regulations will not need to be rewritten until theparent regulation is revised.In accordance with ICL 17-02 (15 Mar 17) to CAPR 173-1, Financial Procedures andAccounting, Financial Management Procedures (FMP) will now be issued assupplements or OIs depending on their purpose. They will be submitted to CAP/FM for approval and posted on the Supplements and OIs publication pages.2.What is the procedure for existing OIs and supplements?All currently approved OIs and supplements must be sent to the CAP/DA,*************** for posting on the publications website. CAP/DA should receive these publications by 7 Nov 16 to satisfy the requirement of paragraph8.3.3.4.If the existing OI or supplement was previously approved by NHQ, they will remain current until the parent regulation (for supplements) is revised. For these publications,recertification will occur on the anniversary of its original implementation date (paragraph8.3.4.).If the existing OI or supplement was not previously approved by NHQ, it needs to besubmitted to the applicable OPR immediately for approval and posting on the publications website.3.Do supplements and OIs require “compliance elements” as Attachment 1?Yes, they do. (Paragraph 7) As a general rule, the existence of supplements and OIs are reviewed during compliance inspections only if the parent regulation requires theirissuance. However, in contrast, the contents (i.e. requirements) of the supplement/OI are usually only assessed for compliance during subordinate unit inspections. Supplement and OI OPRs are responsible for monitoring and tracking subordinate unit compliance.4.Do operating instructions written by the wing apply only to Wing HQ?Yes, OIs are applicable only to the chartered unit issuing them, unlike supplements that are applicable to the issuing unit and all subordinate units. (Paragraph 8.3.2.3. andAttachment 4)5.Our unit has OIs that do not correspond with a specific regulation. What happens to them?The subject matter will still align with a functional department within NHQ and should be sent to that OPR for approval. Keep in mind that supplements and OIs should be usedsparingly. Unless the parent regulation requires a supplement or OI, they should be the exception and not the norm. (Paragraph 8.3.2.1.)6.Where do I find templates for OIs, supplements and waivers?https:///forms_publications__regulations/publications-management/7.I have a policy letter that is critical. What should I do?Carefully review the policy and determine if it is really necessary. If not, rescind the letter.If you believe it critical, rewrite it as a supplement or operating instruction and submit it through your chain of command to the appropriate NHQ office of primary responsibility (OPR).8.How does the regulation effect wing and region communication plans, mission exerciseplans, improvement plans in AARS, etc.?CAPR 1-2 will not affect the development of plans. As a general rule, plans are tools tohelp guide a unit to a desired end state and may provide “how to” information forattaining the desired end state. For example, a disaster response plan guides a unit onhow to recover from a disaster; the desired end state being to return to normal operations.Although a regulation may require development of a plan and direct its minimum contents, the plan itself serves more to promote a readiness posture than a list of “go do”requirements. As such, plans are more closely related to nondirective pamphlets.9.Does my chain of command have to approve every publication?Each parent regulation will eventually define their respective supplement and OI approval process. (Paragraph 8.3.3.) If the supplement or OI is associated with Air Force Assigned Missions or federally provided resources, it must be coordinated with intermediate levels of command and the CAP region and CAP-USAF liaison region prior to being sent to NHQ for approval. (Paragraph 8.3.3.2.)10.Can any unit really issue a pamphlet?Yes, pamphlets are nondirective publications and may be issued at any level unless limited or prohibited by the regulation pertaining to the subject matter. (Paragraph 9)11.Is NHQ approval required to supplement Index 0-2?No, indexes are not directive in nature and may be developed locally without higherapproval. No supplement is needed. (Paragraphs 14.1, 14.2 and 14.3)12.Is there concern NHQ OPRs will be inundated with publications to approve?Although some increase is anticipated, most NHQ OPRs currently review and/or approve supplements and OIs to their respective regulations.Contact CAP/DA, Jeanne Stone at *****************with any additional questions.。