测控专业英语论文
测控技术专业英文自荐信
测控技术专业英文自荐信Dear Hiring Manager,I am writing to express my interest in the position of Measurement and Control Technology at your esteemed organization. With a strong educational background and practical experience in the field, I believe that I would be a valuable asset to your team.I recently graduated with a Bachelor's degree in Measurement and Control Technology from XYZ University. During my studies, I have gained a comprehensive understanding of various measurement techniques, control systems, and network protocols. I have also acquired hands-on experience in using industry-standard software such as LabVIEW, MATLAB, and AutoCAD.In addition to my theoretical knowledge, I have had the opportunity to apply my skills in a real-world setting through internships and projects. As an intern at ABC Company, I was responsible for designing and implementing a control system for a manufacturing process. I collaborated with a team of engineers to analyze the requirements, select appropriate sensors and actuators, and program the controller. This experience has not only enhanced my technical skills but also developed my ability to work effectively in a team.During my final year of study, I conducted a research project focused on the development of a wireless sensor network for environmental monitoring. I was responsible for designing the network architecture, selecting appropriate sensors, and programming the communication protocols. This project not onlyrequired technical skills but also the ability to analyze data and provide meaningful insights. Through this experience, I sharpened my analytical and problem-solving abilities.Apart from my academic and practical experiences, I have also developed strong communication and interpersonal skills. Throughout my studies, I actively participated in group projects and presentations, which allowed me to become a confident and effective communicator. I am comfortable working in diverse teams and am able to contribute my ideas and perspectives while respecting others'.I am highly motivated to work in the field of Measurement and Control Technology as I believe it plays a crucial role in industries such as manufacturing, automation, and telecommunications. I am excited about the opportunity to apply my knowledge and skills to tackle real-world challenges and contribute to the success of your organization.Thank you for considering my application. I would welcome the opportunity to further discuss my qualifications and how I can contribute to your team. I have attached my resume for your review and look forward to hearing from you.Sincerely,[Your Name]Dear Hiring Manager,I hope this email finds you well. I am writing to follow up on my previous email expressing my interest in the position of Measurement and Control Technology at your esteemedorganization. I believe that with my strong educational background and practical experience in the field, combined with my passion for this industry, I would be a valuable asset to your team.During my studies at XYZ University, I gained a comprehensive understanding of various measurement techniques and control systems, as well as the underlying principles of network protocols. My coursework included subjects such as signal processing, instrumentation, industrial automation, and control system design. This solid foundation has equipped me with the necessary knowledge and skills to excel in this field.In addition to the theoretical knowledge gained from my coursework, I have also had the opportunity to apply what I have learned in practical settings. One of my most memorable experiences was during my internship at ABC Company, where I was involved in the design and implementation of a control system for a manufacturing process. Working closely with a team of experienced engineers, I was able to gain valuable hands-on experience in analyzing requirements, selecting appropriate sensors and actuators, and programming the controller. This experience not only solidified my technical skills but also taught me valuable lessons about working effectively in a team and managing project timelines.During my final year of study, I undertook a research project focused on the development of a wireless sensor network for environmental monitoring. This project required me to design the network architecture, select appropriate sensors, and program the communication protocols. Throughout this project, I sharpened myanalytical and problem-solving abilities, as well as my ability to analyze and interpret data. The project also exposed me to the importance of ensuring data accuracy and reliability, as well as the challenges associated with developing robust and scalable network infrastructures.Throughout my academic journey, I actively participated in group projects and presentations, which not only enhanced my technical skills but also honed my communication and interpersonal skills. I have become a confident and effective communicator, able to convey complex technical concepts in a clear and concise manner.I am comfortable working in diverse teams and am able to contribute my ideas and perspectives while respecting and valuing the contributions of others.I am highly motivated to work in the field of Measurement and Control Technology as I believe it plays a crucial role in industries such as manufacturing, automation, and telecommunications. These industries are constantly evolving, and I am excited about the opportunity to apply my knowledge and skills to tackle real-world challenges and contribute to the success of your organization. In conclusion, I would like to reiterate my strong interest in the position of Measurement and Control Technology. I am confident that my strong educational background, practical experience, and passion for this industry make me an excellent fit for your organization. Thank you once again for considering my application.I have attached my resume for your review and look forward to the opportunity to discuss my qualifications further.Sincerely, [Your Name]。
测绘专业英语 论文 作文
Geodesy and the Size and Shape of the Planet EarthMeasuring the Size and Shape of EarthEarth, with average distance of 92,955,820 miles (149,597,890 km) from the sun, is the third planet and one of the most unique planets in the solar system. It formed around 4.5-4.6 billion years ago and is the only planet known to sustain life. This is because factors like its atmospheric composition and physical properties such as the presence of water over 70.8% of the planet allow life to thrive.Earth is also unique however because it is the largest of the terrestrial planets (one that is composed of a thin layer of rocks as opposed to those that are mostly made up of gases like Jupiter or Saturn) based on its mass, density, and diameter. Earth is also the fifth largest planet in the entire solar system.Earth's SizeAs the largest of the terrestrial planets, Earth has an estimated mass of 5.9736 × 1024 kg. Its volume is also the largest of these planets at 108.321 × 1010km3.In addition, Earth is the densest of the terrestrial planets as it is made up of a crust, mantle and core. The Earth's crust is the thinnest of these layers while the mantle comprises 84% of Earth's volume and extends 1,800 miles (2,900 km) below the surface. What makes Earth the densest of these planets however is its core. It is the only terrestrial planet with a liquid outer core that surrounds a solid, dense inner core. Earth's average density is 5515 × 10 kg/m3. Mars, the smallest of the terrestrial planets by density, is only around 70% as dense as Earth.Earth is classified as the largest of the terrestrial planets based on its circumference and diameter as well. At the equator, Earth's circumference is 24,901.55 miles (40,075.16 km). It is slightly smaller between the North and South poles at 24,859.82 miles (40,008 km). Earth's diameter at the poles is 7,899.80 miles (12,713.5 km) while it is 7,926.28 miles (12,756.1 km) at the equator. For comparison, the largest planet in Earth's solar system, Jupiter, has a diameter of 88,846 miles (142,984 km).Earth's ShapeEarth's circumference and diameter differ because its shape is classified as an oblate spheroid or ellipsoid, instead of a true sphere. This means that instead of being of equal circumference in all areas, the poles are squished, resulting in a bulge at the equator, and thus a larger circumference and diameter there.The equatorial bulge at Earth's equator is measured at 26.5 miles (42.72 km) and is caused by the planet's rotation and gravity. Gravity itself causes planets and other celestial bodies to contract and form a sphere. This is because it pulls all the mass of an object as close to the center of gravity (the Earth's core in this case) as possible.Because Earth rotates, this sphere is distorted by the centrifugal force. This is the force that causes objects to move outward away from the center of gravity. Therefore, as the Earth rotates, centrifugal force is greatest at the equator so it causes a slight outward bulge there, giving that region a larger circumference and diameter.Local topography also plays a role in the Earth's shape, but on a global scale its role is very small. The largest differences in local topography across the globe are Mount Everest, the highest point above sea level at 29,035 ft (8,850 m), and the Mariana Trench, the lowest point below sea level at 35,840 ft (10,924 m). This difference is only a matter of about 12 miles (19 km), which is very minor overall. If equatorial bulge is considered, the world's highest point and the place that is farthest from the Earth's center is the peak of the volcano Chimborazo in Ecuador as it is the highest peak that is nearest the equator. Its elevation is 20,561 ft (6,267 m).GeodesyTo ensure that the Earth's size and shape is studied accurately, geodesy, a branch of science responsible for measuring the Earth's size and shape with surveys and mathematical calculations is used.Throughout history, geodesy was a significant branch of science as early scientists andphilosophers attempted to determine the Earth's shape. Aristotle is the first person credited with trying to calculate Earth's size and was therefore, an early geodesist. The Greek philosopher Eratosthenes followed and was able to estimate the Earth's circumference at 25,000 miles, only slightly higher than today's accepted measurement.In order to study the Earth and use geodesy today, researchers often refer to the ellipsoid, geoid and datums. An ellipsoid in this field is a theoretical mathematical model that shows a smooth, simplistic representation of the Earth's surface. It is used to measure distances on the surface without having to account for things like elevation changes and landforms. To account for the reality of the Earth's surface, geodesists use the geoid which is a shape that is constructed using the global mean sea level and as a result takes elevation changes into account.The basis of all geodetic work today though is the datum. These are sets of data that act as reference points for global surveying work. In geodesy, there are two main datums used for transportation and navigation in the U.S. and they make up a portion of the National Spatial Reference System.Today, technology like satellites and global positioning systems (GPS) allow geodesists and other scientists to make extremely accurate measurements of the Earth's surface. In fact it is so accurate, geodesy can allow for worldwide navigation but it also allows researchers to measure small changes in the Earth's surface down to the centimeter level to obtain the most accurate measurements of the Earth's size and shape.。
测控专业 毕业论文 外文翻译 中英文对照
Oscillation, Instability and Control of Stepper Motors LIYU CAO and HOWARD M. SCHWARTZDepartment of Systems and Computer Engineering, Carleton University, 1125 Colonel By Drive,Ottawa, ON K1S 5B6, Canada(Received: 18 February 1998; accepted: 1 December 1998)AbstractA novel approach to analyzing instability in permanent-magnet stepper motors is presented. It is shown that there are two kinds of unstable phenomena in this kind of motor: mid-frequency oscillation and high-frequency instability. Nonlinear bifurcation theory is used to illustrate the relationship between local instability and mid frequency oscillatory motion. A novel analysis is presented to analyze the loss of synchronism phenomenon, which is identified as high-frequency instability. The concepts of separators and attractors in phase-space are used to derive a quantity to evaluate the high-frequency instability. By using this quantity one can easily estimate the stability for high supply frequencies. Furthermore, a stabilization method is presented. A generalized approach to analyze the stabilization problem based on feedback theory is given. It is shown that the mid-frequency stability and the high-frequency stability can be improved by state feedback.Keywords: Stepper motors, instability, nonlinearity, state feedback.1. IntroductionStepper motors are electromagnetic incremental-motion devices which convert digital pulse inputs to analog angle outputs. Their inherent stepping ability allows for accurate position control without feedback. That is, they can track any step position in open-loop mode, consequently no feedback is needed to implement position control. Stepper motors deliver higher peak torque per unit weight than DC motors; in addition, they are brushless machines and therefore require less maintenance. All of these properties have made stepper motors a very attractive selection in many position and speed control systems, such as in computer hard disk drivers and printers, XY-tables, robot manipulators, etc.Although stepper motors have many salient properties, they suffer from an oscillation or unstable phenomenon. This phenomenon severely restricts their open-loop dynamic performance and applicable area where high speed operation is needed. The oscillation usually occurs at stepping rates lower than 1000 pulse/s, and has been recognized as a mid-frequency instability or local instability , or a dynamic instability . In addition, there is another kind of unstable phenomenon in stepper motors, that is, the motors usually lose synchronism at higher stepping rates, even though load torque is less than their pull-out torque. This phenomenon is identified as high-frequency instability in this paper, because it appears at much higher frequencies than the frequencies at which the mid-frequency oscillation occurs. The high-frequency instability has not been recognized as widely as mid-frequency instability, and there is not yet a method to evaluate it.Mid-frequency oscillation has been recognized widely for a very long time, however, acomplete understanding of it has not been well established. This can be attributed to the nonlinearity that dominates the oscillation phenomenon and is quite difficult to deal with.Most researchers have analyzed it based on a linearized model . Although in many cases, this kind of treatments is valid or useful, a treatment based on nonlinear theory is needed in order to give a better description on this complex phenomenon. For example, based on a linearized model one can only see that the motors turn to be locally unstable at some supply frequencies, which does not give much insight into the observed oscillatory phenomenon. In fact, the oscillation cannot be assessed unless one uses nonlinear theory.Therefore, it is significant to use developed mathematical theory on nonlinear dynamics to handle the oscillation or instability. It is worth noting that Taft and Gauthier , and Taft and Harned used mathematical concepts such as limit cycles and separatrices in the analysis of oscillatory and unstable phenomena, and obtained some very instructive insights into the so-called loss of synchronous phenomenon. Nevertheless, there is still a lack of a comprehensive mathematical analysis in this kind of studies. In this paper a novel mathematical analysis is developed to analyze the oscillations and instability in stepper motors.The first part of this paper discusses the stability analysis of stepper motors. It is shown that the mid-frequency oscillation can be characterized as a bifurcation phenomenon (Hopf bifurcation) of nonlinear systems. One of contributions of this paper is to relate the mid-frequency oscillation to Hopf bifurcation, thereby, the existence of the oscillation is proved theoretically by Hopf theory. High-frequency instability is also discussed in detail, and a novel quantity is introduced to evaluate high-frequency stability. This quantity is very easy to calculate, and can be used as a criteria to predict the onset of the high-frequency instability. Experimental results on a real motor show the efficiency of this analytical tool.The second part of this paper discusses stabilizing control of stepper motors through feedback. Several authors have shown that by modulating the supply frequency , the mid-frequency instability can be improved. In particular, Pickup and Russell have presented a detailed analysis on the frequency modulation method. In their analysis, Jacobi series was used to solve a ordinary differential equation, and a set of nonlinear algebraic equations had to be solved numerically. In addition, their analysis is undertaken for a two-phase motor, and therefore, their conclusions cannot applied directly to our situation, where a three-phase motor will be considered. Here, we give a more elegant analysis for stabilizing stepper motors, where no complex mathematical manipulation is needed. In this analysis, a d–q model of stepper motors is used. Because two-phase motors and three-phase motors have the same q–d model and therefore, the analysis is valid for both two-phase and three-phase motors. Up to date, it is only recognized that the modulation method is needed to suppress the mid-frequency oscillation. In this paper, it is shown that this method is not only valid to improve mid-frequency stability, but also effective to improve high-frequency stability.2. Dynamic Model of Stepper MotorsThe stepper motor considered in this paper consists of a salient stator with two-phase or three-phase windings, and a permanent-magnet rotor. A simplified schematic of athree-phase motor with one pole-pair is shown in Figure 1. The stepper motor is usually fed by a voltage-source inverter, which is controlled by a sequence of pulses and produces square-wave voltages. This motor operates essentially on the same principle as that of synchronous motors. One of major operating manner for stepper motors is that supplying voltage is kept constant and frequency of pulses is changed at a very wide range. Under this operating condition, oscillation and instability problems usually arise.Figure 1. Schematic model of a three-phase stepper motor.A mathematical model for a three-phase stepper motor is established using q–d frame-reference transformation. The voltage equations for three-phase windings are given byva = Ria + L*dia /dt − M*dib/dt − M*dic/dt + dλpma/dt ,vb = Rib + L*dib/dt − M*dia/dt − M*dic/dt + dλpmb/dt ,vc = Ric + L*dic/dt − M*dia/dt − M*dib/dt + dλpmc/dt ,where R and L are the resistance and inductance of the phase windings, and M is the mutual inductance between the phase windings. _pma, _pmb and _pmc are the flux-linkages of the phases due to the permanent magnet, and can be assumed to be sinusoid functions of rotor position _ as followλpma = λ1 sin(Nθ),λpmb = λ1 sin(Nθ − 2 /3),λpmc = λ1 sin(Nθ - 2 /3),where N is number of rotor teeth. The nonlinearity emphasized in this paper is represented by the above equations, that is, the flux-linkages are nonlinear functions of the rotor position.By using the q; d transformation, the frame of reference is changed from the fixed phase axes to the axes moving with the rotor (refer to Figure 2). Transformation matrix from the a; b; c frame to the q; d frame is given byFor example, voltages in the q; d reference are given byIn the a; b; c reference, only two variables are independent (ia C ib C ic D 0); therefore, the above transformation from three variables to two variables is allowable. Applying the above transformation to the voltage equations (1), the transferred voltage equation in the q;d frame can be obtained asvq = Riq + L1*diq/dt + NL1idω + Nλ1ω,vd=Rid + L1*did/dt − NL1iqω,Figure 2. a, b, c and d, q reference frame.where L1 D L CM, and ! is the speed of the rotor.It can be shown that the motor’s t orque has the following formT = 3/2Nλ1iqThe equation of motion of the rotor is written asJ*dω/dt = 3/2*Nλ1iq − Bfω – Tl ,where Bf is the coefficient of viscous friction, and Tl represents load torque, which is assumed to be a constant in this paper.In order to constitute the complete state equation of the motor, we need another state variable that represents the position of the rotor. For this purpose the so called load angle _ [8] is usually used, which satisfies the following equationDδ/dt = ω−ω0 ,where !0 is steady-state speed of the motor. Equations (5), (7), and (8) constitute the statespace model of the motor, for which the input variables are the voltages vq and vd. As mentioned before, stepper motors are fed by an inverter, whose output voltages are not sinusoidal but instead are square waves. However, because the non-sinusoidal voltages do not change the oscillation feature and instability very much if compared to the sinusoidal case (as will be shown in Section 3, the oscillation is due to the nonlinearity of the motor), for the purposes of this paper we can assume the supply voltages are sinusoidal. Under this assumption, we can get vq and vd as followsvq = Vmcos(Nδ) ,vd = Vmsin(Nδ) ,where Vm is the maximum of the sine wave. With the above equation, we have changed the input voltages from a function of time to a function of state, and in this way we can represent the dynamics of the motor by a autonomous system, as shown below. This will simplify the mathematical analysis.From Equations (5), (7), and (8), the state-space model of the motor can be written in a matrix form as followsẊ = F(X,u) = AX + Fn(X) + Bu , (10) where X D Tiq id ! _UT , u D T!1 TlUT is defined as the input, and !1 D N!0 is the supply frequency. The input matrix B is defined byThe matrix A is the linear part of F._/, and is given byFn.X/ represents the nonlinear part of F._/, and is given byThe input term u is independent of time, and therefore Equation (10) is autonomous.There are three parameters in F.X;u/, they are the supply frequency !1, the supply voltage magnitude Vm and the load torque Tl . These parameters govern the behaviour of the stepper motor. In practice, stepper motors are usually driven in such a way that the supply frequency !1 is changed by the command pulse to control the motor’s spee d, while the supply voltage is kept constant. Therefore, we shall investigate the effect of parameter !1.3. Bifurcation and Mid-Frequency OscillationBy setting ! D !0, the equilibria of Equation (10) are given asand ' is its phase angle defined byφ= arctan(ω1L1/R) . (16) Equations (12) and (13) indicate that multiple equilibria exist, which means that these equilibria can never be globally stable. One can see that there are two groups of equilibria as shown in Equations (12) and (13). The first group represented by Equation (12) corresponds to the real operating conditions of the motor. The second group represented by Equation (13) is always unstable and does not relate to the real operating conditions. In the following, we will concentrate on the equilibria represented by Equation (12).翻译译文步进电机的振荡、不稳定以及控制摘要本文介绍了一种分析永磁步进电机不稳定性的新颖方法。
和测绘有关的英语作文
和测绘有关的英语作文Surveying and Its Importance in Modern Society。
Surveying is a crucial discipline that plays a significant role in various aspects of our modern society. It involves the measurement and mapping of the Earth's surface, which provides valuable data for a wide range of applications. From construction and infrastructure development to environmental management and urban planning, surveying has become an indispensable tool for ensuring the efficient and sustainable growth of our communities. In this article, we will explore the importance of surveying and its various applications.One of the primary applications of surveying is in the field of construction. Before any construction project can begin, accurate measurements and mapping of the site are essential. Surveyors use advanced equipment such as total stations, GPS receivers, and laser scanners to gather precise data on the topography, boundaries, and existing structures. This information is then used by architects, engineers, and contractors to design and plan the project, ensuring that it is safe, cost-effective, and compliant with regulations.In addition to construction, surveying also plays a crucial role in infrastructure development. Whether it is the construction of roads, railways, or pipelines, surveyors are responsible for determining the optimal routes, assessing the terrain, and identifying any potential obstacles or hazards. By conducting detailed surveys, they can design efficient and sustainable infrastructure systems that minimize environmental impact and maximize resource utilization.Furthermore, surveying is essential for effective environmental management. By accurately mapping the land and monitoring changes over time, surveyors can assess the impact of human activities on the environment. This information is crucial for developing strategies to mitigate environmental risks, preserve natural resources, and protect sensitive ecosystems. For example, surveying is used in forestry to monitor deforestationrates, in agriculture to optimize land use, and in coastal areas to study erosion and sea level rise.Urban planning is another area where surveying plays a vital role. As cities continue to grow and expand, it is essential to plan and manage their development effectively. Surveyors provide valuable data on land use, zoning regulations, and infrastructure requirements, which helps urban planners make informed decisions. By analyzing survey data, they can identify areas for potential development, assess the impact on existing infrastructure, and ensure the efficient use of limited resources.Moreover, surveying is crucial for disaster management and risk assessment. By accurately mapping areas prone to natural disasters such as earthquakes, floods, or landslides, surveyors can help communities prepare for and respond to these events. They can identify high-risk areas, assess vulnerability, and develop evacuation plans. Additionally, surveying is used in post-disaster situations to assess the damage, plan reconstruction efforts, and restore essential services.In conclusion, surveying is a vital discipline that has numerous applications in our modern society. From construction and infrastructure development to environmental management and urban planning, surveyors provide valuable data that is essential for making informed decisions and ensuring the sustainable growth of our communities. By utilizing advanced equipment and techniques, surveyors play a crucial role in shaping our world and creating a better future.。
测控技术外文文献
Development of Sensor New TechnologySensor is one kind component which can transform the physical quantity, chemistry quantity and the biomass into electrical signal. The output signal has the different forms like the voltage, the electric current, the frequency, the pulse and so on, which can satisfy the signal transmission, processing, recording, and demonstration and control demands. So it is the automatic detection system and in the automatic control industry .If automatic Technology is used wider, then sensor is more important.Although there are exception ,most sensor consist of a sensing element diaphragms,bellows,strain tubes and rings, ourdon tubes, and cantilevers are sensing elements which respond to changes in pressure or force and convert these physical quantities into a displacement. This displacement may then be used to change an electrical parameter such as voltage, resistance, capacitance, or inductance. Such combination of mechanical and electrical lements form electromechanical transducing devices or sensor. Similar combination can be made for other energy input such as thermal. The Photo, the magnetic and the chemical,giving thermoelectric, photoelectric,electromaanetic, and electrochemical sensor respectively.The relationship between the measured and the sensor output signal is usually obtained by calibration tests and is referred to as the sensor sensitivity increment measured increment. In practice, the sensor sensitivity is usually known, and, by measuring the output signal, the input quantity is determined from increment K1.In information age, the information industry includes information gathering, transmission, process three parts, namely sensor technology, communication, computer technology. Because of ultra large scale integrated circuit’s rapid development after having been developed Modern computer technology andcommunication, not only requests sensor precision reliability, speed of response and gain information content request more and more high but also requests its cost to be inexpensive. The obvious traditional sensor is eliminated gradually because of the function, the characteristic, the volume, the cost and so on. As world develop many countries are speeding up to the sensor new technology’s research and the development, and all has obtained the enormous breakthrough. Now the sensor new technology development mainly has following several aspects.Using the physical phenomenon, the chemical reaction, the biological effect as the sensor principle therefore the researches which discovered the new phenomenon and the new effect are the sensor technological improving ways .it is important studies to developed new sensor’s the foundation. Japanese Sharp Corporation uses the superconductivity technology to develop successfully the high temperature superconductivity magnetic sensor and get the sensor technology significant breakthrough. Its sensitivity is so high and only inferior in the superconductivity quantum interference component. Its manufacture craft is far simpler than the superconductivity quantum interference component. May use in magnetism image formation technology. So it has the widespread promoted value.Using the immune body and the antigen meets one another compound when the electrode surface. It can cause the electrode potential change and use this phenomenon to be possible to generate the immunity sensor. The immunity sensor makes with this kind of immune body may to some organism in whether has this kind of ant original work inspection. Like may inspect somebody with the hepatitis virus immune body whether contracts the hepatitis, plays to is fast, the accurate role. The US UC sixth branch has developed this kind of sensor.The sensor material is the important foundation for sensor technology, because the materials science is progressive and the people may make each kind of new sensor For example making the temperature sensor with the high polymerthin film; The optical fiber can make the pressure, the current capacity, the temperature, the displacement and so on the many kinds of sensors; Making the pressure transmitter with the ceramics. The high polymer can become the proportion adsorption and the release hydrogen along with the environment relative humidity size. The high polymer electricity lies between the constant to be small, the hydrogen can enhance the polymer the coefficient of dialectical loss. Making the capacitor the high polymer dielectric medium, determines the electric capacity cape city the change, then obtains the relative humidity. Making the plasma using this principle to gather the legitimate polystyrene film temperature sensor below, it has the characteristic.The ceramic electric capacity type pressure transmitter is one kind does not have the intermediary fluid the dry type pressure transmitter. Uses the advanced ceramic technology, the heavy film electronic technology, its technical performance is stable, the year drifting quantity is smaller than 0.1%F.S, warm floats is smaller than ±0.15%/10K, anti- overloads strongly, may reach the measuring range several hundred times. The survey scope may from 0 to 60mpa.German E+H Corporation and the American Kahlo Corporation product is at the leading position.The optical fiber application is send the material significant breakthrough, its uses in most early the optical communication techniques. In the optical communication use discovered works as environmental condition change and so on the temperature, pres-sure, electric field, magnetic field, causes the fiber optic transmission light wave intensity, the phase, the frequency, change and so on the polarization condition, the survey light wave quantity change, may know causes these light wave physical quantity the and so on quantitative change temperature, pressure ,electric field, magnetic field size, uses these principles to be possible to develop the optical fiber sensor. The optical fiber sensor and the traditional sensor compare has many characteristics: Sensitivity high, the structure simple, the volume small, anti-corrosive, the electric insulation good, the path of raysmay be curving, be advantageous for the realization telemeter and so on. Optical fiber sensor Japan is in the advanced level. Like Idec Izumi Corporation and Sun x Corporation. The optical fiber send receiver and the integrated path of rays technology unify, accelerates the optical fiber sensor technology development. Will integrate the path of ray’s component to replace the original optics part and the passive light component; enable the optical fiber sensor to have the high band width, the low signal processing voltage, the reliability high, the cost will be low.The sensor’s development is changing day after day since especially the 80's humanities have entered into the high industrialization the information age, sensor techno-logy to renewal, higher technological development. US, Japan and so on developed country sensor technological development quickest, our country because the foundation is weak, the sensor technology compares with these developed countries has the big disparity. Therefore, we should enlarge to the sensor engineering research, the development investment, causes our country sensor technology and the foreign disparity reduces, promotes our country instrument measuring appliance industry and from the technical development.传感器新技术的发展传感器是一种能将物理量、化学量、生物量等转换成电信号的器件。
测控专业英语考试作文
测控专业英语考试作文精选英文测控专业英语考试作文：Title: The Vital Role of Measurement and Control Engineering in Modern IndustriesIn the ever-evolving landscape of modern industries, Measurement and Control Engineering (MCE) stands as a cornerstone, enabling precise monitoring, optimization, and automation of complex processes. This interdisciplinary field, which blends the principles of physics, mathematics, computer science, and electronics, has revolutionized production lines, enhanced safety standards, and driven technological advancements across diverse sectors such as manufacturing, aerospace, healthcare, and environmental monitoring.The Foundation of Precision and EfficiencyAt the heart of MCE lies the quest for precision. By employing highly sophisticated sensors and instrumentation, engineers can accurately measure various physical quantities like temperature, pressure, flow rate, and displacement. This data, when coupled with advanced control algorithms, enables real-time adjustments to systems, ensuring optimal performance and minimizing errors. For instance, in the automotive industry, MCE systems monitor engine performance, adjusting fuel injection and ignition timing for maximum fuel efficiency and reduced emissions.Automation and the Industrial Revolution 4.0The advent of Industrial Revolution 4.0, also known as the Smart Factory era, has underscored the importance of MCE. This paradigm shift emphasizes the integration of cyber-physical systems, Internet of Things (IoT), and big data analytics, all of which relyheavily on accurate measurements and intelligent control strategies. MCE provides the necessary framework for implementing autonomous systems, predictive maintenance, and supply chain optimization. By automating mundane tasks and facilitating decision-making based on real-time data, MCE has significantly boosted productivity, reduced downtime, and enhanced overall competitiveness.Safety and Reliability in Critical InfrastructuresIn sectors where safety and reliability are paramount, such as nuclear power plants, oil and gas refineries, and chemical processing facilities, MCE plays a vital role. Sophisticated control systems monitor the state of equipment and processes, alerting operators to potential hazards and automatically initiating safety protocols when necessary. For example, in nuclear power stations, MCE systems continuously monitor radiation levels, coolant flow, and reactor pressure, ensuring compliance with stringent safety regulations and preventing accidents.Innovations in HealthcareMCE's influence extends beyond traditional industrial settings, permeating into the healthcare industry. Medical devices like MRI scanners, ultrasound machines, and patient monitoring systems rely on precise measurements and control algorithms to provide accurate diagnoses and treatments. Furthermore, the integration of wearable devices and remote monitoring systems has revolutionized patient care, enabling early detection of health issues and facilitating personalized medicine.Environmental StewardshipLastly, MCE contributes significantly to environmental sustainability efforts. Bymonitoring air and water quality, tracking greenhouse gas emissions, and managing waste disposal processes, engineers can devise effective control strategies to mitigate environmental impacts. For instance, smart waste management systems use sensors to monitor waste levels and optimize collection routes, reducing fuel consumption and carbon emissions.In conclusion, Measurement and Control Engineering is a cornerstone of modern industries, driving innovation, enhancing efficiency, and ensuring safety across various sectors. As technology continues to advance, the demand for skilled MCE professionals will undoubtedly grow, necessitating ongoing education, research, and collaboration among stakeholders. The future holds immense promise for this dynamic field, as it continues to shape the way we live, work, and protect our planet.中文对照翻译：题目：测控工程在现代工业中的重要作用在现代工业不断发展的格局中，测量和控制工程（MCE）是一个基石，可以实现复杂过程的精确监控、优化和自动化。
测绘专业的英文作文
测绘专业的英文作文英文：As a surveying and mapping major, I think this profession is both challenging and rewarding. The main task of surveying and mapping is to measure and map the land, which requires a high level of accuracy and precision. The use of advanced technology such as GPS and GIS has greatly improved the efficiency and accuracy of surveying and mapping.However, surveying and mapping is not just about measuring and mapping the land. It also involves a lot of problem-solving and decision-making. For example, when designing a new road or building, surveyors need to take into account various factors such as topography, soil conditions, and environmental impact. They also need to consider the needs of the community and ensure that their designs are safe and practical.Another aspect of surveying and mapping that I find interesting is the ability to work outdoors. Surveyors often work in remote locations and encounter various challenges such as extreme weather conditions and difficult terrain. However, this also allows them to experience the beauty of nature and explore new places.Overall, I believe that surveying and mapping is a profession that requires both technical skills and creativity. It is a challenging but rewarding career that offers opportunities for personal and professional growth.中文：作为一名测绘专业的学生，我认为这个专业既具有挑战性又具有回报性。
2018-测控技术与仪器科技英语-word范文 (12页)
本文部分内容来自网络整理，本司不为其真实性负责，如有异议或侵权请及时联系，本司将立即删除！== 本文为word格式，下载后可方便编辑和修改！ ==测控技术与仪器科技英语篇一：测控技术与仪器科技英语第四课翻译与课文Unit 4Digital Signal Processing (DSP)Having heard a lot about digital signal processing (DSP) technology , investigate why DSP is preferred to analog circuitry for many types of operations , and discover how to learn enough to design your own DSP system .This article , the first of a series , is an opportunity to take a substantial first step towards finding answers to your question .This series is an introduction to DSP topics from the point of analog system designers seeking additional tools for handing analog signal. Designers reading this series can lean about the possibilities of DSP to deal with analog signals and where to find additional sources of information and assistance.4.1 What Is DSP?In brief, DSPs are processors or microcomputers whose hardware, software, and instruction sets are optimized high-speed numeric processing applications-an essential for processing digital data representing analog signals in real time. What a DSP does is straightforward. When acting as a digital filter, for example, the DSP receives digital values based on samples of a signal, calculates the results of a filter function operating on these values, and provides digital values that represent the filter output; it can also provide system control signals based on properties of these values. The DSP’s high-speed arithmetic and logical hardware is programmed to rapidly execute algorithms modeling the filter transformation.The combination of design elements a arithmetic operators, memory handling, instruction set, parallelism, data addressing that provide this ability forms the key difference between DSPs and other kinds of processors. Understanding the relationship between real-time signal and DSP Calculation speed provides some background on just how special this combination is .The real-time signal comes to the DSP asa train of individualsamples from an analog-to-digital converter (ADC) .To do filtering in real-time, the DSP must complete all the calculations and operations required for processing each samples (usually updating a process involving many previous samples ) before the next sample arrives. To perform high-order filtering of real-world signals having significant frequency content calls for really fast processors.4.2 Why Use a DSP?To get an ideal of the type of calculations of DSP dose and get an ideal of how an analog circuit compares with a DSP system , one could compare the two systems in terms of a filter function. The familiar analog filter uses resistors ,capacitors,inductors ,amplifiers .It can be cheap and easy to assemble ,but difficult to calibrate,modify, and maintain a difficulty that increases exponentially with filter order .For many purposes, one can more easily design ,modify,and depend on filters using a DSP because the filter function on the DSP is software-based, flexible ,and repeatable.Further,to createflexibly adjustable filter s with higher-order response requires only software modifications,with no additional hardware unlike purely analog circuits .An ideal bandpass filter,with the frequency response shown in Fig.4.1,would have the following characteristics:? a response within the passband that is completely flat with zero phase shift? infinite attenuation in the stopband.Useful additions would include:? passband tuning and width control? Stopband rolloff controlAs Fig.4.1 shows, an analog approach using second-order filters would require quite a few staggered high-Q sections; the difficulty of tuning and adjusting it can beimagined.With DSP software ,there are two basic approaches to filter design : finite impulse response (FIR) and infinite impulse response(IIR) .The FIR filter's time response to an impulse is thestraightforward weighted sum of the present and a finite number of previousinput samples. Having no feedback,its response to a given sample ends when the sample reaches the "end of the line "(Fig. 4 . 2). An FIR filter's frequency response has no poles, only zeros. The IIR filter , by comparison, is called infinite because it is a recursivefunction:its output is a weighed sum of inputs and outputs. Since itis recursive , its response can continue indefinitely . An IIR filter frequency response has both poles and zeros. .The x(s) are the input samples, y(s) are the output samples, a(s) are input sample weighings, and b(s) are sample weighings. Nis thepresent sample time, and M and N are the number of samples programmed (the filter's order). Note that the arithmetic operations indicatedfor both types are simply sums and products in potentially great number. In fact ,multiply-and-add is the case for many DSP algorithms that represent mathematical operations of great sophistication and complexity.Approximating an ideal filter consists of applying a transferfunction with appropriate coefficients and a high enough order , or number of taps (considering the train of input samples as tappeddelay line). Fig. 4.3shows the response of a 90-tap FIR filter compared with sharp-cutoff Chebyshev filters of various orders. The90-tap example suggests how close the filter can come toapproximating an ideal filter. Within a DSP system, programming a 90-tap FIR filter like the one in Fig. 4.3 is not a difficult task. By comparison, it would no be cost-effective to attempt this level of approximation with a purely analog circuit. Another crucial point in favor of using a DSP to approximate the ideal fillter is long-term stability. With an FIR (or an IIR having sufficientresolution to avoid truncation-error buildup), the programmable DSP achieves the same response,time after time. Purely analog filter responses of high order areless stable with time.Mathematical transform theory and practice are the core requirementfor creating DSP application and understanding their limits. This article series walks through a few signal-analysis and-processing examples to introduce DSP concepts. The series also provides references to texts for further study and identifies software tools that case the development of signal-processing software.4.3 Sampling Real-world SignalsReal-world phenomena are analog the continuously changing energylevels of physical processes like sound, light, heat, electricity, magnetism, A transducer converts these levels into manageableelectrical voltage and current signals, and an ADC sampling frequency, of the ADC is critically important in digital processing processingof real-world signals.This sampling rate is determined by the amount of signal information that is needed for processing the signal adequately for a given application. In order for an ADC to provide enough samples to accurately describe the real-world signal, the sampling rate must beat least twice the highest-frequency component of the analog signal. For example, to accurately describe an audio signal containing frequencies up to 20kHz, the ADC must sample the signal at a minimumof 40kHz. Since arriving signal can easily contain component frequencies above 20kHz (including noise), they must be removedbefore sampling by feeding the signal through a low-pass filter, is intend to remove the frequencies above 20kHz that could corrupt the converted signal.However, the anti-aliasing filter has a finite frequency rolloff, so additional bandwidth must be provided for the filter's transition band. For example, with an inputsignal bandwidth of 20kHz, one might allow 2 to 4kHz of extra bandwidth.Figure 4.4 depicts the filter needed to reject any signals with frequencies above half of a 48kHz sampling rate.Second sample .The time between samples is the time budget for the DSP to preform all processing tasks.For the audio example ,a 48kHz sample rate corresponds to a 20.833vs sampling interval. Fig.4.5 relates the the analog signal and digital sample rate .图Next consider the relation between the speed of the DSP andcomplexity of the algorithm (the software containing the transform or other set of numeric operations ).Complex algorithm require more processing tasks.Because the time between samples is fixed ,thehigher complexity calls for faster processing .For example ,suppose that the algorithm requires 50 processing operations to be performed。
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主要内容：
测控技术与仪器专业属于仪器仪表类专业，现代测控依靠智能仪器仪表，智能仪器也是现代工业生产中运用的一种现代化测量控制仪器。
本文主要简单介绍了什么是智能仪器以及其发展状况和特点。
最后说明了随着计算机技术和微电子技术的进一步发展，智能仪器将会向微型化，多功能，人工智能化，网络化方向发展。
本文简单介绍了什么是智能仪器的人工智能化，什么是智能仪器的网络化。
虚拟仪器是智能仪器发展的新的阶段。
Development of intelligent instrument
Measurement and control technology and instrument specialty is the acquisition and processing of information, as well as to the related theory and technology factor model control.with the continuous development of computer technology and microelectronics technology, has now been mature application in measurement and control system, the typical representative of intelligent instrument is the application.
Intelligent instrument is a measuring instrument with microcomputer ormicro processor ,has small volume, strong function, low power consumption.In 80 the microprocessor is applied to together, instrument front panel began to develop in the direction of the keyboard, the measurement system is often connected by a bus.In intelligent instrument outstanding performance in the following areas: advances in microelectronics and more profound impact on instrument design; the DSP chip is published, the instrument digital signal processing functions greatly enhanced; the development of the microcomputer, the instrument has the stronger ability of data processing; image processing function is increasing common VXI bus is widely used.The emergence of intelligent instrument to improve the measuring precision of the instruments, which greatly facilitates the maintenance of equipment.In recent years, digital self-tuning regulator development of intelligent measurement and control instrumentation such as American rapidly American production company FOXBORO, which combines expert system technologies,can be like control engineer experienced that, according to the scene quickly tuning parameters.This control system is especially suitable for the regulator object changes frequently or nonlinear. Because of this regulator can automatically tuning control parameters, which can make the whole system to always maintain the best state in the process of production.
With the continuous development of computer technology and microelectronics technology, intelligent instrument in future will be towards miniaturization, multifunction, artificial intelligence, networking. Artificial intelligence is a new field of computer application, using computer to simulate human intelligence, for each robot, medical diagnosis, expert system, reasoning and proof.The further development of intelligent instrument will contain a certain artificial intelligence, namely, to replace part of mental labor, which has certain ability in the visual, hearing, thinking and so on. Thus, the intelligent instrument without human intervention and independently to complete the detection or control function.The further development of intelligent instrument will contain a certain artificial intelligence, namely, to replace part of mental labor, which has certain ability in the visual, hearing, thinking and so on.
In future, virtual instrument is a new stage of the development of intelligent instrument. 测控1601 35。