A framework for navigation-driven lazy mediators
太空科技英语
太空科技英语The Boundless Realm of Space TechnologyHumanity's enduring fascination with the cosmos has long driven us to explore the great unknown beyond our planet. From the earliest stargazers to the modern-day pioneers of space exploration, the lure of the heavens has captivated our collective imagination. Today, the field of space technology has evolved into a vast and rapidly advancing discipline, offering unprecedented opportunities for scientific discovery, technological innovation, and the expansion of human knowledge.At the forefront of this remarkable journey are the visionary scientists, engineers, and innovators who dedicate their lives to unraveling the mysteries of the universe. Through the development of cutting-edge spacecraft, sophisticated instrumentation, and groundbreaking computational capabilities, these individuals are pushing the boundaries of what is possible, unlocking new frontiers in our understanding of the cosmos.One of the most significant areas of space technology is the design and construction of advanced spacecraft. From the sleek andefficient rockets that propel us into orbit to the intricate modules and habitats that allow us to establish a presence beyond Earth, these engineering marvels are the embodiment of our quest for interplanetary exploration. With each new generation of spacecraft, we witness remarkable advancements in materials science, propulsion systems, and onboard technologies, paving the way for longer, more complex missions that venture deeper into the solar system and beyond.Alongside the development of spacecraft, the realm of space technology also encompasses the design and deployment of sophisticated scientific instruments. These highly specialized tools, ranging from powerful telescopes that peer into the farthest reaches of the universe to sensitive detectors that measure the subtle nuances of planetary atmospheres, are instrumental in our quest to unravel the fundamental laws that govern the cosmos. Through the data collected by these instruments, scientists are able to make groundbreaking discoveries, from the detection of exoplanets to the mapping of dark matter, expanding our understanding of the universe in unprecedented ways.But the impact of space technology extends far beyond the realms of scientific exploration. In the modern era, space-based technologies have become deeply integrated into our daily lives, transforming the way we communicate, navigate, and access information. The globalnetwork of satellites that orbit our planet has revolutionized telecommunications, enabling instant connectivity and the seamless exchange of data across vast distances. Similarly, satellite-based navigation systems have become indispensable for everything from personal travel to global logistics, providing us with precise positioning and guidance capabilities that have become integral to the functioning of our modern societies.Moreover, the development of space technology has also led to numerous spin-off technologies that have found widespread applications in various industries. From advanced materials and manufacturing techniques to cutting-edge medical technologies and renewable energy solutions, the innovations born out of space exploration have had a profound impact on our daily lives, driving progress and improving the human condition in ways that were once unimaginable.As we gaze towards the future, the potential of space technology only continues to grow. With ambitious plans for long-term human settlements on the Moon and Mars, the establishment of permanent orbital outposts, and the exploration of the outer reaches of our solar system, the coming decades promise to be a truly transformative era in the history of human spaceflight. These bold endeavors will not only expand our scientific understanding of the universe but also pave the way for the development of newtechnologies that could revolutionize our way of life on Earth.However, the realization of these visionary goals is not without its challenges. The inherent complexities and risks associated with space exploration require the coordinated efforts of governments, private enterprises, and international collaborations to overcome. Securing the necessary funding, navigating the logistical and technological hurdles, and ensuring the safety of both human and robotic explorers are just a few of the formidable obstacles that must be addressed.Despite these challenges, the boundless potential of space technology continues to captivate and inspire us. As we venture forth into the great unknown, we do so with a sense of wonder and a profound appreciation for the transformative power of human ingenuity. The future of space exploration is not only a testament to our species' unwavering spirit of exploration but also a testament to our unwavering commitment to pushing the boundaries of what is possible, for the betterment of humanity and the preservation of our planet.。
认识方向与位置英语作文
认识方向与位置英语作文Title: Understanding Directions and Locations。
In our daily lives, understanding directions and locations is crucial for navigating through various places effectively. Whether it's finding your way in a new city or locating a specific destination, possessing knowledge of directions and locations enhances our ability to movearound efficiently and confidently.Firstly, it's essential to grasp cardinal directions, namely north, south, east, and west. Understanding these directions provides a foundational framework for navigation. For instance, knowing that the sun rises in the east and sets in the west helps in determining direction, especially when landmarks or compasses are unavailable.Secondly, mastering relative directions is equally important. Terms like "left," "right," "ahead," and "behind" are used to describe locations in relation tooneself or other objects. For instance, when someone says, "Turn left at the traffic light," they are providing a relative direction based on the observer's perspective.Furthermore, familiarizing oneself with landmarks aids in navigation. Landmarks serve as reference points and help in identifying locations within a particular area. Whether it's a prominent building, a distinctive tree, or a notable statue, landmarks provide visual cues that assist in orienting oneself and understanding directions more effectively.Moreover, understanding distances is crucial for estimating travel time and planning routes. Distances can be measured in various units such as kilometers, miles, or meters. Knowing the approximate distance between two points enables individuals to gauge the feasibility of walking, driving, or taking public transportation to reach their destination.Additionally, utilizing maps and navigation tools has become increasingly common in modern times. Digital mapsand GPS devices provide real-time directions and suggest the fastest routes to a destination. These tools not only display accurate directions but also offer additional features such as traffic updates and alternate routes, enhancing the overall navigation experience.Furthermore, learning directional expressions in different languages can be beneficial, especially when traveling to foreign countries. Basic phrases like "Where is...?" and "How do I get to...?" enable individuals to seek assistance and communicate effectively with locals when navigating unfamiliar territories.In conclusion, understanding directions and locationsis a fundamental skill that facilitates efficient navigation and enhances one's overall travel experience. By mastering cardinal and relative directions, familiarizing oneself with landmarks, estimating distances, and utilizing maps and navigation tools, individuals can navigate through various environments with confidence and ease. Moreover, learning directional expressions in different languages broadens communication capabilities and fosters culturalappreciation. Ultimately, acquiring proficiency in understanding directions and locations empowers individuals to explore the world and navigate through life's journeys with confidence.。
2023-2024学年江苏省常州市联盟学校高一下学期期末学情调研英语试题
2023-2024学年江苏省常州市联盟学校高一下学期期末学情调研英语试题Scientists play a crucial role in advancing technology and improving our quality of life. Consider thework of Marie Curie, who discovered radium and polonium, opening up new frontiers in the field ofradioactivity and laying the foundation for modern nuclear medicine. Her research has led to the development of life-saving treatments and diagnostic（诊断的）tools that have benefited countless patients.Another remarkable scientist is Albert Einstein. His theory of relativity changed our understanding of the universe, challenging conventional wisdom and inspiring countless subsequent studies in physics. This has not only deepened our knowledge of the cosmos but also led to technological advancements such as GPS navigation, which relies on the principles of relativity for correct positioning.Isaac Newton’s laws of motion and universal gravitation provided a framework for understanding the physical world and paved the way for modern engineering and aerospace technology. The applications of his theories are obvious in everything from the construction of buildings to the launch of satellites.Charles Darwin’s theory of evolution by natural selection transformed our understanding of the diversity of life on Earth. It has had far-reaching implications in fields such as genetics, ecology, and conservation biology, guiding our efforts to protect and preserve the natural world.Nikola Tesla’s contributions to electri cal engineering, particularly in the development of alternating current（交流电）, have powered our modern world. Without his innovations, our reliance on electricity for lighting, communication, and countless other applications would be severely limited.1. Who discovered radium and polonium?A．Albert Einstein. B．Isaac Newton.C．Marie Curie. D．Charles Darwin.2. Which of the following is a major and biggest difference between Albert Einstein and Isaac Newton?B．Their nationality.A．The field of science they mainlycontributed to.D．Their educational background.C．The century in which they did theirresearch.3. Which of the following is a common feature shared by all the scientists mentioned?A．They all made their discoveries in the 20th century.B．They were all from the same country.C．They all faced significant opposition to their work during their lifetimes.D．They all had a deep and lasting impact on the advancement of science and humanknowledge.My childhood memory is closely connected with hunger. Unable to provide enough food to feed its ever-increasing population, the People’s Republic had to adopt a food ration（定量）system to ensure equal supply of food for three decades—the ration for an adult in an urban area was 15 kilograms of wheat, rice, com or sorghum per month.Many young people today might not understand why I’m talking about hunger when an adult’s monthly quota for food grains was 15kg, especially because half of that would perhaps be enough for them for a month. But that’s all an adult c ould consume up to the 1970s, because cooking oil, meat, eggs and sugar were strictly controlled.Although the ration system ensured everybody had a share of the available food and prevented starvation deaths, it led to malnutrition（营养不良）among people of every age.On launching reform and opening-up. China realized a major reason for food shortage was farmers not getting their rightful due under the system then. So the government distributed the collectively-owned farmlands to households and farmers. Within years, the farm yield almost doubled, helping China to abandon the food rationing system in 1993.Now, enough food supply and much money have changed Chinese people’s dietary habits. Many youths refuse to learn cooking, arguing that they can source their meals from restaurants or take-out outlets. As a result, one can see thousands of electric bike riders zigzagging the streets to deliver breakfast, lunch or dinner.Paradoxically, Chinn is now battling over-nutrition. One would be lucky to not find a few overweight boys and girls in a class. When I meet with my former classmates, many of whom are overweight or suffering from over-nutrition-related illnesses, we sometimes talk about the “good old food ration days” when almost no one needed to worry about con trolling weight.4. What is the main purpose of China’s adopting a food ration system?A．To feed enough food to people. B．To ensure less waste of food.C．To avoid increase of population. D．To fight against food shortage.5. What can we infer from paragraph 2?A．Lacking other nutrition made 15kg food grains not enough for an adult.B．Young people today consume less food grains to avoid overweight problem.C．People in poverty had no access to oil, meat, eggs and sugar in the 1970s.D．The farm yield almost doubled with the development of faring technology.6. What does the underlined word “Paradoxically” in Paragraph 5 most probably mean?A．Consequently. B．Unexpectedly.C．Similarly. D．Reasonably.7. Why does the author write the article?A．To suggest our country adopting food ration again.B．To advise people to have enough food.C．To record the change in the development of society.D．To introduce a healthy lifestyle to young people.Playing music requires fine motor skills, which are controlled in both hemispheres（大脑半球）of the brain. It also combines language and mathematics, which the left hemisphere is more involved in, with the novel and creative content that the right does well in. For these reasons, playing music has been found to increase the volume and activity in the brain’s corpus callosum（肼胝体）, the bridge between the two hemispheres, allowing messages to get across the brain faster and through more different ways. This may allow musicians to solve problems more effectively and creatively, in both academic and social settings.Because making music also involves creating and understanding its emotional content and message, musicians often have higher levels of decision-making function, a category of interlinked tasks that includes planning, strategizing, and attention to detail and requires immediate analysis of both cognitive（认知的）and emotional aspects. This ability also has an impact on how our memory systems work. And, indeed, musicians exhibit better memory functions, creating, storing, and retrieving memories more quickly and efficiently. Studies have found that musicians appear to use their highly connected brains to give each memory multiple tags（标签）, such as a conceptual tag, an emotional tag, an audio tag, and a contextual tag, like a good Internet search engine.How do we know that all these benefits are unique to music, as opposed to, say, sports or painting? Or could it be that people who go into music were already smarter to begin with? Neuroscientists have explored these issues, but so far, they have found that the artistic and aesthetic aspects of learning to play a musical instrument are different from any other activity studied, including other arts. And several randomized（随机的）studies of participants, who showed the same levels of cognitive function and neural processing at the start, found mat those who were exposed to a period of music learning showed improvement in multiple brain areas, compared to the others.8. Which of the following could be the best title for the passage?A．The Connection Between Music and Brain Activity.B．The Secret of Musicians’ Success.C．How Music Changes Our Lives.D．The Impact of Music on Motor Skills.9. What does playing music increase in the brain?A．The size of the left hemisphere.B．The size of the right hemisphere.C．The volume and activity in the brain’s corpus callosum.D．The number of neural connections in the front part of brain.10. What have neuroscientists found about-the benefits of playing music?A．They are not unique. B．They are the same as those of sports.C．They are the same as those of painting. D．They are different from any other activitystudied.11. What did the randomized studies find about those exposed to music learning?A．They had worse cognitive function.B．They showed no improvement in brain areas.C．They showed improvement in duty brain area.D．They showed improvement in multiple brain areas.Last week a study was published showing that people with bowel cancer（肠癌）who drink coffee—quite a lot of coffee, two to four cups a day—were less likely to suffer a return of the disease. Experts have said that if the results hold in further studies, coffee could be prescribed（开处方）to cancer patients on the NHS（National Health Service）. That coffee does have an effect on human function is no doubt—but whether that impact is beneficial or harmful has been controversial（有争议的）since its beginning in the mid-15th century.The native peoples of the forests of Kaffa in south-west Ethiopia searched for berries（浆果）from wild coffee plants that were shipped across the Red Sea to prepare the decoction（煮出的汁）known as qahwa, which was used to reduce their desire for sleep. Once mainstream Islamic courts said coffee was not poisonous, consumption became widespread among the Muslim populations in the Middle East and the Ottoman empire.First regarded as a form of medicine, Turkish traders introduced coffee to Venice, where it was prescribed for digestive disorders. It was served in small, cold potions. London’s first coffee houses appeared in the 1650s, attracting customers with the advertised health benefits of the new beverage. However, not all were convinced. The 1674 Women’s Petition Against Coffee declared that too much coffee consumption weakened men and made them unproductive.Since the 1960s, mass surveys of coffee drinkers have shown different results of its impact. In 1991 the World Health Organization listed coffee as a possible cause of cancer, but in 2016 this conclusion was reversed（反转）as more studies have shown a larger number of positive outcomes being associated with coffee drinking. Following centuries on the defensive（处于守势）, it may be time for coffee professionals to dust down those handbills and channel their inner Pasqua Rosée.12. What was the main finding of the recent study mentioned in paragraph 1?A．Coffee has no impact on human function.B．Drinking coffee reduces the risk of bowel cancer.C．People with bowel cancer should avoid drinking coffee.D．Coffee has no effect on the return of bowel cancer.13. Why does the writer mention the history of coffee consumption?A．To highlight the cultural significance of coffee in different regions.B．To emphasize the historical controversy around coffee’s health effects.C．To show coffee’s long-standing popularity and usage.D．To show the link between coffee’s origins and its medical applications.14. Which is the most suitable title for this passage?A．The Dark Side of Coffee: A Hidden Cancer RiskB．The Bitter Drink: Coffee’s Secret in Being PopularC．Uncovering the Truth: Coffee’s Cancer-Fighting HistoryD．Surprising History of Coffee: From Controversial Drink to Potential Cancer Cure15. Which section of the journal might this article belong to?A．Health & fitness. B．Home & garden.C．History & Culture. D．Finance & investment.Around 1830, the Romantic period slowly arose from the delicate form of the Classical period, expanding orchestral（管弦乐的）forces to express emotions and extra-musical ideas they had never expressed before. How was this possible? 16Romantic Period SoundIf you expect the music to have a regular, eight bar phrase（乐节）, think again. It might have irregular phrases to throw you off course, like in Schubert’s ‘Unfinished’ Symphony No. 8. 17 It may well be that composers like Mahler jump to an unexpected musical ending, like in his Symphony No. 2. If in doubt, be prepared to forget anything and everything you previously thought about music, and expect to be surprised, attracted, and amazed by the unexpected twists and turns of the Romantic period.Romantic InstrumentsAs music grew more expressive, the standard orchestral instruments just weren’t rich enough for many Romantic composers. So, more were added, including the contrabassoon, bass clarinet and piccolo, xylophones, drums, celestes, harps, bells, and triangles. 18 Listen to how Tchaikovsky makes use of various instruments in the ‘Dance of the Sugar Plum Fairy’ in his ballet, The Nutcracker.Romantic PiecesDespite often being marked as a Classical period composer, Beethoven’s style really covered the two periods. His later works are pretty expansive, conjuring（变戏法般的）life, death, joy, peace, and even the concept of a universal brotherhood in the symphony of all symphonies, his choral Symphony No. 9, written in 1824. 19 It was a one-movement work evoking a story or poem, like Debussy’s dreamy Prélude à l’après-midi d’un faune or Dukas’ Sorcerer’s Apprentice.20 They also expanded the orchestra to express the full range of human emotion through music. But, understandably, this over-indulgent expression had its critics（批判者）who favoured absolute music-music for music’s sake, without a programme or story-and these critics led music into the ever-diverse 20th Century period.After being poorly bred（饲养）by a backyard breeder. Stevie was ________ at a rescue. She was born ________, so her breeder had no ________ to sell her. As soon as Stevie’s parents became aware of her situation, they immediately offered to ________ her. Her eyes were infected（感染）badly and she had congenital glaucoma（先天性背光眼）. Since she never had ________ to begin with, the vet（兽医）decided to ________ her eyes to relieve pain.Slowly, she started to heal from all the trauma（创伤）she had been through. Her adopt（收养）parents became more and more ________ to her. A ________ was made that Stevie would stay as a family member for the rest of her life. She now lives an adventure-packed life with her pup friends. Stevie has no problems ________ as she gradually learned to “feel” her way. She enjoys hikes, camping trips, and even helps other adopted dogs feel ________ in her home. Stevie has shown people that a dog with a（n）________ can live a healthy and happy lifestyle. Eventually, the family also tuned to The Endless Pawsabilities Rescue Society for help. The Endless Pawsabilities Rescue Society is a non-profit organization ________ to animal welfare（福利）. Furthermore, they actively support North American rescue and adoption ________.Stevie’s story became a beacon（灯塔）of hope for countless animals in need. She became a（n）________ of the unbreakable spirit that animals possess. ________ everyone that every pet, regardless of their challenges, deserves a loving home.21.A．bought B．abandoned C．attacked D．disliked 22.A．deaf B．unhappy C．blind D．broken23.A．reason B．secret C．course D．clue24.A．buy B．forgive C．sell D．keep25.A．ability B．sight C．hearing D．sense26.A．cover B．remove C．widen D．reduce27.A．equal B．closed C．attached D．cruel28.A．wish B．notice C．movement D．decision 29.A．going away B．getting over C．getting around D．going through 30.A．active B．popular C．confident D．comfortable 31.A．disability B．specialty C．difference D．interest32.A．admitted B．used C．addicted D．devoted 33.A．performances B．efforts C．battles D．answers 34.A．symbol B．signal C．imagination D．fact35.A．pushing B．helping C．proposing D．reminding阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
navigationlink 用法详解-概述说明以及解释
navigationlink 用法详解-概述说明以及解释1. 引言概述部分的内容可以从navigationlink的定义和作用开始介绍，然后可以描述一下我们为什么要详细了解navigationlink的用法。
可以这样编写概述部分的内容：1.1 概述NavigationLink是SwiftUI中的一个重要视图链接，用于在不同的视图之间进行导航和页面跳转。
它可以实现在用户点击按钮、文本或其它视图时，切换到目标视图的功能。
NavigationLink的设计使得我们可以快速构建具有导航功能的应用程序。
了解NavigationLink的用法对于开发者来说是非常重要的，因为它是构建iOS、iPadOS和watchOS上导航功能的关键组件之一。
NavigationLink可以通过声明式语法在代码中定义，也可以通过参数来自定义其样式和行为。
在本文中，我们将深入研究NavigationLink的用法，并探讨其各种参数的含义和作用。
我们将从NavigationLink的基本用法开始，然后逐步介绍其更高级的用法和一些常用的技巧。
通过学习NavigationLink的详细用法，我们将能够更好地理解和应用它，从而更加灵活和高效地构建导航功能。
因此，让我们开始全面了解NavigationLink的各种用法和应用场景吧！1.2 文章结构文章主要由引言、正文和结论三部分组成。
1. 引言：在引言部分，我们将对NavigationLink进行概述，介绍其作用和重要性。
我们还会提供一些背景信息，包括其在iOS开发中的应用广泛程度和现有的其他导航相关组件。
2. 正文：正文部分将分为三个小节，分别介绍NavigationLink的基本用法、参数说明和高级用法。
- 2.1 NavigationLink的基本用法：我们将详细介绍如何使用NavigationLink来创建一个简单的导航链接，并展示其在导航视图中的效果。
我们会讲解如何设置目标视图、添加导航按钮以及在导航之间传递数据。
无人驾驶英语PPT
Motion Planning
It determines the specific actions, including acceleration, braking, and steering, that the vehicle needs to take along the planned path
Global Path Planning
This technique plans a complete route for the vehicle from the start to the destination, considering all possible traffic scenarios and objectives
要点二
Semantic Segmentation
It allows the vehicle to understand the scene in detail by assigning semantic means to different parts of the environment
要点三
3D Reconstruction
Level 4
High automation The vehicle can handle most or all driving tasks without human intervention, but limited to specific geographic regions and weather conditions.
Public transportation
Autonomous vehicles can be used for shared rides, shuttle services, or even fully automated bus systems, providing effective and sustainable transportation options for urban areas
数学翻译成英语
数学翻译成英语Mathematics is one of the fundamental branches of knowledge that deals with the study of numbers, quantities, shapes, and patterns. It encompasses a wide range of concepts and techniques used to solve problems, make predictions, and understand the world around us.The origins of mathematics can be traced back to ancient civilizations, such as the Egyptians and Mesopotamians, who developed basic arithmetic and geometric principles. Over the centuries, mathematicians have built upon these foundations and developed sophisticated theories and methods.One of the key areas in mathematics is algebra, which deals with the manipulation and study of mathematical symbols and equations. Algebra allows us to solve equations, analyze patterns, and understand relationships between different variables. It is widely used in fields such as physics, engineering, and computer science.Another important branch of mathematics is geometry, which focuses on the properties and relationships of shapes. Geometry provides a framework for understanding spatial relationships and is crucial in fields like architecture, design, and navigation.Calculus is another essential area in mathematics, developed by Sir Isaac Newton and Gottfried Leibniz in the 17th century. It provides a powerful tool for analyzing and modeling continuous change. Calculus is used extensively in physics, economics, and statistics. Probability and statistics are also crucial in mathematics, dealingwith the study of uncertainty and randomness. Probability allows us to quantify the likelihood of events occurring, while statistics enables us to analyze and interpret data. These fields are essential in areas such as finance, medicine, and social sciences.Mathematics is not just a theoretical discipline, but also has practical applications in the real world. It is widely used in areas such as engineering, finance, computer science, and cryptography. For example, mathematicians use algorithms to encrypt and secure data in computer networks, and they develop mathematical models to predict and analyze financial markets.Furthermore, mathematics plays a crucial role in scientific research, providing a language and framework for formulating theories and making predictions. It enables physicists to describe the laws of nature through equations, and biologists to model population dynamics and genetics.In conclusion, mathematics is a universal language that helps us understand and describe the world around us. It provides a systematic approach to problem-solving and enables us to make sense of complex phenomena. Whether it is used to calculate the trajectory of a space shuttle or analyze data in a clinical trial, mathematics is an essential tool for modern society.。
航海知识面试英语
航海知识面试英语在航海领域，英语是一门至关重要的语言。
无论是在船舶操纵、通信、导航还是与其他国际航海相关方进行交流，英语都扮演着不可或缺的角色。
在航海知识面试中，考官往往会对英语能力进行测试，以确保申请人具备足够的沟通能力和专业知识。
本文将介绍一些常见的航海知识面试英语问题以及如何回答它们。
1. 自我介绍Question: Can you introduce yourself briefly?Answer: Hello, my name is [Your Name]. I have a strong passion for the maritime industry, which led me to pursue a career in navigation. I hold a Bachelor’s degree in Maritime Studies and have completed my mandatory sea time as a deck cadet. During my time at sea, I gained hands-on experience in various navigation techniques and vessel operations. I am also adept at using navigational equipment such as GPS, radar, and ECDIS. I am confident in my ability to contribute to a safe and efficient maritime environment.2. 航海术语Question:What is the difference between “port” and “starboard”?Answer:“Port” refers to the left side of a vessel when facing forward, while “starboard” refers to the right side. These terms are essential for communication and navigation on board a ship. By using “port” and “starboard,” sailors can provide clear instructions to each other, especially when maneuvering in tight spaces or during docking operations.3. 航海安全Question: What safety measures should be taken before setting sail?Answer: Before setting sail, several safety measures should be taken to ensure a safe voyage. These include conducting a thorough pre-departure check of the vessel’s equipment, ensuring that life-saving appliances, such as life jackets and life rafts, are in good condition and readily accessible. Additionally, verifying that all navigation and communication systems are in working order is vital. It is also important to review weather conditions and consult relevant charts and publications before departure. Lastly, a comprehensive crew briefing on emergency procedures and contingency plans should be conducted.4. 航行规则Question: What are the International Regulations for Preventing Collisions at Sea (COLREGS)?Answer:The COLREGS, also known as the “Rules of the Road,” ar e a set of international regulations that establish the legal framework for preventing collisions at sea. They provide guidelines on the actions to be taken by vessels in various situations to avoid collisions. The COLREGS cover a range of topics, including navigation lights, right of way, sound signals, and maneuvering rules. It is crucial for all mariners to be familiar with and adhere to these regulations to ensure safe navigation.5. 航海通信Question: What are the common communication methods used at sea?Answer: Communication is vital in maritime operations. Common communication methods used at sea include VHF radio, satellite communication systems, and Morse code. VHF radio is widely used for ship-to-ship and ship-to-shore communication, while satellite communication systems enable long-distance communication and provide access to weather reports and navigational information. Morse code, although less common nowadays, is still used as a backup method for distress signals and emergency communication.6. 航海导航Question: What is the purpose of a navigational chart?Answer: A navigational chart is a map specifically designed for navigation purposes. It provides essential information for safe and efficient navigation, including water depths, navigational aids, landmarks, and potential hazards. By using a navigational chart, mariners can plan and monitor their routes, avoid obstacles, and ensure that their vessels stay within safe navigable waters.结论航海知识面试英语涵盖了许多方面，包括航海术语、航海安全、航行规则、航海通信和航海导航等。
a-frame iscustomelement -回复
a-frame iscustomelement -回复什么是A-Frame？A-Frame是一种用于构建虚拟现实（VR）体验的开源Web框架。
它是基于HTML的，可以在任何支持WebGL的浏览器中工作。
A-Frame提供简单易用的语法和组件来创建交互式的3D场景和VR体验，使开发者能够轻松构建属于自己的虚拟现实世界。
A-Frame与其他VR开发框架相比的优势是什么？1. 使用简单：A-Frame基于HTML，采用类似于HTML的标记语言，使开发者能够在不需要掌握复杂的VR编程技术的情况下创建虚拟现实内容。
2. 开放性：A-Frame是开源项目，任何人都可以查看和修改其源代码。
这使得A-Frame社区能够共同推动该框架的发展，从而为开发者提供更多功能和改进。
3. 可扩展性：A-Frame提供了丰富的组件库，可以通过简单地添加和配置组件来实现复杂的交互和效果。
此外，开发者还可以通过自定义组件来扩展A-Frame的功能，满足特定的需求。
4. 跨平台支持：A-Frame可以在任何支持WebGL的浏览器中运行，包括桌面浏览器、移动浏览器和VR设备。
这种跨平台的支持使得开发者能够将他们的虚拟现实内容展示给更广泛的受众。
如何开始使用A-Frame？1. 引入A-Frame库：在HTML文件中引入A-Frame库的CDN（内容分发网络）链接，以便浏览器可以加载和解析A-Frame代码。
2. 创建场景：使用`<a-scene>`标签创建一个场景容器，类似于HTML 文档的`<body>`标签。
在场景中，可以添加各种元素和组件来构建虚拟现实世界。
3. 添加实体：使用`<a-entity>`标签来添加虚拟现实世界中的实体，比如物体、角色、相机等。
可以通过直接在HTML中进行静态创建，也可以通过JavaScript动态创建。
4. 配置组件：使用`<a-component>`标签来配置实体的组件。
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Abstract
BBQ User Interface
XML Application
user navigations client navigations We propose a framework for navigation-driven evalua- virtual XML view tion of virtual mediated views. The approach is based (DOM-VXD) partial results partial results on lazy mediators that translate incoming client naviga- XMAS view Lazy Mediator mq1 XMAS view Lazy Mediator mq2 de nition q2 tions on a virtual XML view (or the result of an XML de nition q1 source navigations source navigations query) into navigations on wrapped sources or lower level mediators. Such a demand-driven approach is inpartial results partial results evitable in order to handle up-to-date mediated views of OODB-XML RDB-XML HTML-XML Wrapper Wrapper Wrapper huge Web sources or large query results, which are commonplace when querying the Web. The proposed MIX mediator provides to the client an abstraction of the OODB DOM API, the de facto API to XML documents, hence Web sites RDB hiding the non-materialization of the view or the query. We also describe the inherent navigational complexity of queries and view de nitions wrt. navigations. Next, we Figure 1: DOM-VXD mediation architecture discuss the query/navigation processing aspects of the MIX mediator. The mediator translates a view into an algebraic plan. Then each operator of the algebraic plan In the MIX1 system we take the lazy mediator apacts as a navigation-driven lazy mediator. This allows proach to its full potential using the architecture of Figto characterize the complexity of plans and to compare ure 1. The common model for data exchange is XML their navigational complexity. XML98b]. Mediator views are expressed in XMAS2 , a declarative XML query language, which is very similar to XML-QL XML98a] and YAT CDSS98]. Nevertheless most of the concepts and results presented next are orthogonal to the details of the semistructured model Mediated views integrate information from heteroge- and the query language. neous sources. There are two main paradigms for evalu- An application, such as the B lended B rowsing and ating queries against integrated views: In the eager (or Q uerying (BBQ) interface BGL+ 99], may directly acwarehousing ) approach, data is collected and integrated cess the view or issue a query against the view and conprior to the execution of user queries against the mate- sequently access the query result. In the balance of the rialized views. However, when the user is interested in paper we assume that the application directly accesses the most recent data available and/or huge (or poten- the view. The case of issuing a query against the view tially in nite) views, then a lazy (or demand-driven ) ap- is handled by replacing the view with the composition proach has to be employed. Most notably such requirethe ments are encountered when considering integration of of The query and the view. the view using a subset of application accesses Web sources. For example, consider a mediator which navigation commands of the DOM3 API. However, the integrates data on books available from and lazy mediator MIXm does not materialize the view . Clearly, a warehousing approach in advance. Instead, view materialization based on all available books is not viable. In the lazy documentby the application's navigation. The mediais driven approach, however, the user query against the mediated view will be decomposed at the mediator and corre1 Mediation of Information using XML MIX99]. 2 XML Matching And Structuring Language LPVV99]. sponding subqueries will be sent to the sources at query 3 D ocument O bject M odel DOM98]. evaluation time.
A Framework for Navigation-Driven Lazy Mediators
Bertram Ludascher Yannis Papakonstantinou Pavel Velikhov
ludaesch@
fyanny mediator mq for a view de nition q operates as follows: The client navigates into the virtual view exported by mq by issuing DOM navigation commands on the view document exported by the mediator. For each command ci that the mediator receives (Figure 2), a minimal source navigation is sent to each source. Note that navigations sent to the sources depend on the client navigation, the view de nition, and the state of the lazy mediator. The results of the source navigations are then used by the mediator to generate the result for the client and to update the mediator's state.
1 Introduction and Overview