1、Geographical information systems 地理信息系统
Geo-referenced data 地理参照数据 data capture 数据获取
Data integration 数据集成projection and registration 投影与匹配
Data structures 数据结构information retrieval 信息检索
Topological modeling 拓扑建模network analysis网络分析
Overlay 叠置 data output 数据输出
2、discrete objects 离散对象raster data 格数据
Vector data 矢量数据continuous fields 连续字段
Spatial data model 空间数据模型digital terrain model（DTM）数字地面模型
Digital elevation model（DEM）数字高程模型Exhaustive enumeration 穷举法run-length encoding 行程长度编码
Hierarchical file 层次文件
relational file 关系文件
3、geo-referencing 空间参照geodesy 大地测量学
Map projections 地图投影coordinate systems 坐标系统
Datum 基准面ellipsoid 椭球体
Geoid大地基准面gravity 万有引力
Earth’ s spherical graticule 地球球面坐标网Cartesian coordinates 笛卡尔坐标
Lambert azimuthal equal-area projection 朗伯等积方位投影
Polar coordinate 极坐标gnomonic projection 心射切面投影
Albers equal-area conic projection 阿尔伯斯等积圆锥投影
Developable surface 投影面orthographic projection 正射投影
4、location 定位attribute 属性
Arcs（lines）弧线
polygons（traversed areas）多边形
Points（labeled nodes）点（标识节点） nodes （intersection points）节点（交汇点）
Data collection 数据采集color aerial photograph 彩色航空照片
Synthetic aperture radar 合成孔径雷达benchmark point 基准点
Scanner 扫描仪on-screen / heads-up digitizing 幕数字化Uncertainty 不确定性error 误差
Accuracy 准确性precision 精确性
Topology creation 拓扑创建indexing 索引
5、spatial analysis 空间分析database query 数据库查询
Reclassification 重分类generalization 概括
Ranking 分级geometry 几何学
Overlay analysis 叠加分析
connectivity analysis 连通性分析
Spatial interpolation 空间插值standard query language（SQL）标准化查询语言Polygon 多边形proximity analysis 邻近域分析
Network analysis 网络分析Geo-statistics 地统计学
Inverse distance weighted interpolation（IDW）反距离加权内插法
Geo-visualization 空间可视化
6、environmental management and conservation 环境管理与保护
Environmental planning 环境规划landscape 景观
Environmental hazards and risks 环境灾害与监测Environmental assessment and monitoring 环境评价与监测
Environmental model 环境模型air pollution & control 大气污染与控制Disaster management 灾害管理public health 公共卫生
Site analysis 位置分析
health insurance organization 健康保险组织Health care 卫生保健
7、remote sensing 遥感sensor 传感器
Electromagnetic radiation 电磁辐射radiometer 辐射计
Electro-optical scanner 光学扫描仪radar system 雷达系统
Platform 遥感平台electromagnetic spectrum 电磁波谱
Electrical field 电场magnetic field 磁场
Blackbody 黑体Planck radiation law 普朗克定律
Stefan-Boltzmann’s law 波尔兹曼定律Wien’s displacement law 维恩位移定律
Rayleigh scattering 瑞利散射Mie scattering 米氏散射
Nonselective scattering 非选择性散射atmospheric windows 大气窗口
specular reflector 镜面反射perfect diffuse reflector 漫反射（朗伯反射）
irregular reflector 不规则反射spectral reflectance curve 反射波谱曲线
8、platform 遥感平台meteorological satellite 气象卫星
TIRO-1（Television and Infrared Observation Satellite-1）电视和红外辐射观测卫星-1
Near-polar orbit 近极地轨道sun-synchronous 太阳同步轨道
GOES（Geostationary Operational Environmental Satellite）静止同步环境应用卫星
Advanced Very High Resolution Radiometers(AVHRR)甚高分辨率辐射计
Return beam vidicon 反束光导摄像管multispectral Scanner（MSS）多光谱扫描仪Thematic Mapper 专题测图仪pushbroom 推扫式
SPOT（Systeme Pour l’ Observation de la Terre）地球观察卫星系统
CNES（Centre National d’ Etudes Spatiales国家空间研究中心）
high resolution visible（HRV）sensors 高分辨可视成像传感器
Charge-coupled devices （CCDs）电荷耦合器件panchromatic（PLA）全色multispectral（MLA）多波段
WFI(Wide Field Imager)广角成像仪 earth observing system（EOS）地球观测系统
CBERS(China-Brazil Erath Resources Satellite)
中巴地球资源卫星
IRMSS(Infrared Multispectral Scanner) 红外多光
谱扫描仪
MODIS(Moderate Resolution Imaging Spectro-radiometer)中分辨率成像光谱仪
Coastal Zone Colour Scanner（CZCS）海按去彩色
扫描器
Marine Observation Satellite (MOS) 莫斯（海洋
观测卫星）
Multispectral Electronic Self-scanning Radiometer (MESSR) 多光谱电子自扫描仪辐射计Visible and Thermal Infrared Radiometer (VTIR) 可见光与热红外辐射计
Microwave Scanning Radiometer (MSR) 微波扫描
辐射计
SeaWiFS(Sea-viewing Wide-Field-of View Sensor)
Lecture 1 INTRODUCTION TO EARTH Major Concept (I) The planets in our solar system, including Earth, began to form out of a rotating disk of gas and dust about 4.6 billion years ago. Related or supporting concepts: The present view of the beginning of the solar system suggests that a cloud of gas and dust was flattened into a disk by rotation. The density of the matter in the disk was greatest at its center and decreased toward the edges. The sun formed at the center of the disk where the temperature was highest and the planets formed at greater distances away from the center. The compositions of the planets differ because of a natural sorting of elements in the cloud with distance from the center. The temperature of the early Earth was probably quite high due to: a. the gravitational capture of particles that released heat on impact, b. the increased pressure on the interior of the planet as it continued to grow, and c. the capture of radioactive elements that gave off heat when they decaye d. During the first few hundred million years, the internal temperature rose high enough to melt iron and nickel. These heavy metals sank to form the core of the planet and displaced lighter material that rose to form chemically differentiated shells. Major Concept (II) Earth’s oceans originated early in the planet’s history. There are two proposed sources of the water in the oceans. Related or supporting concepts: The oldest sedimentary rocks found that required water for their formation are 3.9 billion years old. This suggests that there are been oceans on Earth for roughly 4 billion years. Traditionally scientists have believed that the water in the oceans and atmosphere originated in Earth’s mantle and was brought to the surface by volcanism. Most magmas contain from 1% to 5% dissolved gas by weight, most of which is water vapor. If we assume that the current rate of release of water vapor in volcanic eruptions has remained essentially constant for the past 4 billion years, then the volume of water expelled(put out) during that time would be roughly 100 times the volume of today’s oceans. A relatively new proposal is that a significant amount of water is added to Earth from space when small icy comets（彗星）enter Earth’s atmosphere. The early atmosphere did not have any oxygen. The oxygen released from the interior of the planet would have combined with metals at the surface to produce oxides. It wasn't until large amounts of oxygen were produced after plants formed that it began to accumulate in the atmosphere. Major Concept (III)
Financial management is an integrated decision-making process concerned with acquiring, financing, and managing assets to accomplish some overall goal within a business entity. 财务管理是为了实现一个公司总体目标而进行的涉及到获取、融资和资产管理的综合决策过程。 Decisions involving a firm’s short-term assets and liabilities refer to working capital management. 决断涉及一个公司的短期的资产和负债提到营运资金管理 The firm’s long-term financing decisions concern the right-hand side of the balance sheet. 该公司的长期融资决断股份资产负债表的右边。 This is an important decision as the legal structure affects the financial risk faced by the owners of the company. 这是一个重要的决定作为法律结构影响金融风险面对附近的的业主的公司。 The board includes some members of top management(executive directors), but should also include individuals from outside the company(non-executive directors). 董事会包括有些隶属于高层管理人员(执行董事)，但将也包括个体从外公司(非执行董事)。 Maximization of shareholder wealth focuses only on stockholders whereas maximization of firm value encompasses all financial claimholders including common stockholders, debt holders, and preferred stockholders. 股东财富最大化只集中于股东，而企业价值最大化包含所有的财务债券持有者，包括普通股股东，债权人和优先股股东。 Given these assumptions，shareholders’ wealth maximization is consistent with the best interests of stakeholders and society in the long run。 根据这些假设，从长期来看，股东财富最大化与利益相关者和社会的最好利润是相一致的。 No competing measure that can provide as comprehensive a measure of a firm’s standi ng. Given these assumptions, shareholders’ wealth maximization is consistent with the best interests of stakeholders and society in the long run. 没有竞争措施，能提供由于全面的一个措施的一个公司的站。给这些臆说，股东'财富最大化一贯不比任何人差项目干系人项目利益相关者的利益，社会从长远说来。 In reality, managers may ignore the interests of shareholders, and choose instead to make investment and financing decisions that benefit themselves. 在现实中，经理可能忽视股东的利益，而是选择利于自身的投资和融资决策。 Financial statements are probably the important source of information from which these various stakeholders(other than management) can assess a firm’s financial health. 财务报表可能是最重要的信息来源，除管理者以外的各种利益相关者可以利用这些报表来评估一个公司的财务状况。 The stockholders’ equity section lists preferred stock, common stock and capital surplus and accumulated retained earnings. 股东权益列示有优先股，普通股，资本盈余和累积留存收益。 The assets, which are the “things” the company owns, are listed in the order of decreasing liquidity, or length of time it typically takes to convert them to cash at fair market values, beginning with the firm’s current assets. 资产，也就是公司拥有的东西，是按照流动性递减的顺序或将它们转换为公允市场价值所需要的时间来排列的，通常从流动资产开始。The market value of a firm’s equity is equal to the number of shares of common stock outstanding times the price per share, while the amoun t reported on the firm’s balance sheet is basically the cumulative amount the firm raised when issuing common stock and any reinvested net income(retained earnings). 公司权益的市场价值等于其发行在外的普通股份数乘以每股价格，而资产负债表上的总额则主要是公司在发行普通股以及分配任何再投资净收益（留存收益）时累积的数额。 When compared to accelerated methods, straight-line depreciation has lower depreciation expense in the early years of asset life, which tends to a higher tax expense but higher net income. 与加速折旧法相比,直线折旧法在资产使用年限的早期折旧费用较低，这也会趋向于较高的税金费用和较高的净收入。 The statement of cash flows consists of three sections:(1)operating cash flows,(2)investing cash flows, and(3)financing cash flows. Activities in each area that bring in cash represent sources of cash while activities that involve spending cash are uses of cash. 该声明现金流量表包含三个部分:(1)经营现金流,(2)投资的现金流,(3)融资现金流。在每个地区活动带来现金来源的现金而代表活动涉及到花钱是使用现金 Financing activities include new debt issuances, debt repayments or retirements, stock sales and repurchases, and cash dividend payments. 筹资活动,包括发行新债券，偿还债务，股票销售和回购，以及现金股利支付。 Not surprisingly, Enron’s executives had realized some $750 million in salaries, bonuses and profits from stock options in the 12 months before the company went bankrupt. 毫不奇怪, 公司破产前的十二个月里，安然的高管们实现了7.5亿美金的工资、奖金和股票期权利润。First, financial ratios are not standardized. A perusal of the many financial textbooks and other sources that are available will often show differences in how to calculate some ratios. 首先,财务比率不规范。一个参考的许多金融教科书及来源,可将经常表现出差异如何计算一些率。 Liquidity ratios indicate a firm’s ability to pay its obligations in the short run. 流动性比率表明公司的支付能力在短期内它的义务。 Excessively high current ratios, however, may indicate a firm may have too much of its long-term investor-supplied capital invested in short-term low-earning current assets. 当前的比率过高,然而,可能表明,一个公司可能有太多的长期 investor-supplied资本投资于短期low-earning流动资产 In an inflationary environment, firms that use last-in, first-out(LIFO)inventory valuation will likely have lower current ratios than firms that use first-in, first-out(FIFO). 在一个通货膨胀的环境下,企业选择使用后进先出法对存货计价的公 司比采用先进先出法的公司有一个低的流动比率。 The cash ratio is too conservative to accurately reflect a firm’s liquidity position because it assumes that firms can fund their current liabilities with only cash and marketable securities. 流动比率太稳健不能正确反映一个公司的流动性状况，因为在这一比率假定公司仅仅用现金和有价证券就可以偿还流动负债。 Debt management ratios characterize a firm in terms of the relative mix of debt and equity financing and provide measures of the long-term debt paying ability of the firm. 描述一个公司债务管理比率从相对的混合的债务和股权融资的措施, 提供长期偿债能力的公司。 Total capital includes all non-current liabilities plus equity, and thus excludes short-term debt. 资本总额包括所有非流动负债加上股本,从而排除短期贷款。 Net profit margins vary widely by the type of industry. 有着很大的不同,其净利润为典型的产业。 Note that earnings before interest and taxes, rather than net income, Is used in the numerator because interest is paid with pre-tax dollars, and the firm’s ability to pay current interest is not affected by taxes. 注意,分子中用的是息税前利润而不是净收入，这是因为利息是税前支付的，公司支付现金利息的能力不受税收的影响。 Managers should analyze the tradeoff between any increased sales from a more lenient credit policy and the associated costs of longer collection periods and more uncollected receivables to determine whether changing the firm’s credit sales policy could increase shareholder’s we alth. 管理者应该分析权衡增加的销售从一个更为宽松的信贷政策和相关费用较长的周期和更多的应收账款收集来决定是否改变公司的信用销售的政策可能会增加股东的财富。 If the receivables collection period exceeds a firm’s credit terms this may indicate that a firm is ineffective in collecting its credit sales or is granting credit to marginal customers. 如果应收账款采集时间超过公司的信用条款这也许说明了企业信用销售收集它无效或给予客户信用边缘。 A low, declining ratio may suggest the firm has continued to build up inventory in the face of weakening demand or may be carrying and reporting outdated or obsolete inventory that could only be sold at reduced prices, if at all. 一个低税率、下降率可能显示这个公司已经持续不断地加强库存面对需求不断减弱或可能携带和报告过期或过时的库存,只能减价出售。Thus, the operating profit margin, which indicates the operating profit generated per dollar of net sales, measures t he firm’s operating profitability before financing costs. 因此,经营利润,预示着美元营业利润产生的净销售额,公司的经营利润措施在融资成本。 If the firm’s fixed assets are old and have been depreciated to a low book value, and the assets have not lost their productive ability, the low figure in the denominator will inflate ROA. 如果公司固定资产比较旧,分母的减少会是ROA折旧到低的账面价值，但是资产并没有失去生产能力。 Return on common equity(ROCE) focuses on just the return to common shareholders and is computed by removing the dividends to preferred shareholders from net income and dividing by the capital provided by common shareholders. 普通股权益报酬率仅仅关注普通股股东的报酬率，用净收入扣除优先股股利除以普通股股东提供的资本计算得到。 Dividend yield represents parts of a stock’s total return; another part of a st ock’s total return is price appreciation. 代表部分股息率的股票总回报;另一部分是一个股票的总回报价格上涨。 In fact, of all the concepts used in finance, none is more important than the time value of money, also called discounted cash flow(DCF) analysis. 事实上,财务上所有的概念中，货币时间价值是最重要的，也称作是折现调整现金流量折价分析。
通信工程常用专业英语简写中英文翻译 3GPP 3rd Generation Partnership Project 第三代合作伙伴计划 1x RTT cdma2000 1x Radio Transmission Technology cdma2000 第一代无线接入技术 ACK Acknowledge 确认 ACLR Adjacent Channel Leakage power Radio 邻信道泄露功率比 ACS Adjacent Channel Selectivity 邻信道选择性 AMC Adaptive Modulation and Codeing自适应编码调制 A-MPR Additional Maximum Power Reduction 额外最大功率回退 AoA Angle of Arrival 到达角 AoD Angle of Departure 离开角 ARQ Automatic Repeat request自动重传请求 AS Angel Spread 角度扩展 AWGN Additive White Gaussian Noise 加性高斯白噪声 B3G Beyond 3rd Generation 后三代 BCCH Broadcast Control Channel 广播控制信道 BCH Broadcast Channel 广播信道 BD Block Diagonalization块状对角化 BER Bit Error Rate 误比特率 BLER Block Error Rate误块率 BM-SC Broadcast-Multicast Service Centre 广播/多播业务中心 BSR Buffer Status Reports 缓存状态报告 CA Carrier Aggregation 载波聚合 CBRM Circular Buffer Rate Matching 循环缓存速率匹配 CC Component Carrier 成员载波 CC Chase Combine Chase聚合 CCCH Common Control Channel 公共控制信道 CCCH Common Control Channel 公共控制信道 CCE Control Channel Element 控制信道单元 CCO Coverage and Capacity Optimization 容量与覆盖优化 CCO Cell Change Order 小区改变命令 CCSA China Communication Standards Association 中国通信标准化协会 CDD Cyclic Delay Diversity 循环延迟分集 CDMA Code Division Multiple Access 码分多址接入 cdma2000 Code Division Multiple Access 2000码分多址2000接入系统 CFI Control format Indicator 控制格式指示 CGI Cell Global Identifier 全球小区标识 CoMP Coordinated Multi-Point transmission 协调多点传输 CP Cylic Prefix 循环前缀 CPM Conference Preparing Meeting 大会准备会议 CQI Channel Quality Indicator 信道质量指示 CRC Channel Redundancy Check 信道冗余校验 B-RNTI Cell-Radio Network Temporary Identifier 小区无线网络临时标识
Chapter 1 Passage 1 Human Body In this passage you will learn: 1. Classification of organ systems 2. Structure and function of each organ system 3. Associated medical terms To understand the human body it is necessary to understand how its parts are put together and how they function. The study of the body's structure is called anatomy; the study of the body's function is known as physiology. Other studies of human body include biology, cytology, embryology, histology, endocrinology, hematology, immunology, psychology etc. 了解人体各部分的组成及其功能，对于认识人体是必需的。研究人体结构的科学叫解剖学；研究人体功能的科学叫生理学。其他研究人体的科学包括生物学、细胞学、胚胎学、组织学、内分泌学、血液学、遗传学、免疫学、心理学等等。 Anatomists find it useful to divide the human body into ten systems, that is, the skeletal system, the muscular system, the circulatory system, the respiratory system, the digestive system, the urinary system, the endocrine system, the nervous system, the reproductive system and the skin. The principal parts of each of these systems are described in this article. 解剖学家发现把整个人体分成骨骼、肌肉、循环、呼吸、消化、泌尿、内分泌、神经、生殖系统以及感觉器官的做法是很有帮助的。本文描绘并阐述了各系统的主要部分。 The skeletal system is made of bones, joints between bones, and cartilage. Its function is to provide support and protection for the soft tissues and the organs of the body and to provide points of attachment for the muscles that move the body. There are 206 bones in the human skeleton. They have various shapes - long, short, cube - shaped, flat, and irregular. Many of the long bones have an interior space that is filled with bone marrow, where blood cells are made. 骨骼系统由骨、关节以及软骨组成。它对软组织及人体器官起到支持和保护作用，并牵动骨胳肌，引起各种运动。人体有206根骨头。骨形态不一，有长的、短、立方的、扁的及不规则的。许多长骨里有一个内层间隙，里面充填着骨髓，这即是血细胞的制造场所。 A joint is where bones are joined together. The connection can be so close that no movement is possible, as is the case in the skull. Other kinds of joints permit movement: either back and forth in one plane - as with the hinge joint of the elbow - or movement around a single axis - as with the pivot joint that permits the head to rotate. A wide range of movement is possible when the ball - shaped end of one bone fits into a socket at the end of another bone, as they do in the shoulder and hip joints. 关节把骨与骨连接起来。颅骨不能运动，是由于骨与骨之间的连接太紧密。但其它的关节可允许活动，如一个平面上的前后屈伸运动，如肘关节；或是绕轴心旋转运动，如枢轴点允许头部转动。如果一根骨的球形末端插入另一根骨的臼槽里，大辐度的运动（如肩关节、髋关节）即成为可能。 Cartilage is a more flexible material than bone. It serves as a protective, cushioning layer where bones come together. It also connects the ribs to the breastbone and provides a structural base for the nose and the external ear. An infant's skeleton is made of cartilage that is gradually replaced by bone as the infant grows into an adult. 软骨是一种比一般骨更具韧性的物质。它是骨连结的保护、缓冲层。它把肋骨与胸骨连结起来，也是鼻腔与内耳的结构基础。一个婴儿的骨骼就是由软骨组成，然后不断生长、
引言Introduction 人文地理学，作为科学王国中一支较小的学科，尽管常常不被人们关注和重视，然而它却是一支最具活力的学科，它的研究主题——社会的空间组织和人与环境的关系——为许许多多形式的研究和朝气蓬勃的地理学者提供了机遇和挑战。在最近30年来，西方人文地理学可以说是百家争鸣、百花齐放。人文地理学家不断地接受他们以前很少遇到的其它学科的新思想、新观念，这样就给人文地理学的发展带来无限的生机。 Human geography is such a subject full of vitalities despite of being neglected sometimes.Its research themes, the social-spatial structure and the relationship between human and environments, have brought opportunities and challenges to both various forms of research and geographers.In recent 30 years, the western human geography has so many variegated theories and ramifications.Human geographers have kept absorbing new ideas and opinions from many other subjects, which gives tremendous vital force to the development of human geography. 一、人文地理学的性质 Characters of human geography 1、地理学形成及分化 Formation and differentiation of geography 地理学（geography）是希腊语中关于地球和书写两个词复合词，主要研究人类生活空间的地球表面（Haggett，1990）。 Geography mainly studies the earth sphere that people live in. 大学地理学的发展一开始就受到自然科学和人文社会科学两大类学科分化的影响，研究自然环境的地理学称为“自然地理学”，研究人工环境的称“人文地理学”。 Geography studied in university had ramifications about “physical geography”and “human geography”because its development had been affected by the differentiation of natural science and social science from the beginning. 随着科学的进步和社会需求的出现，地理学的定义也在不断地发生变化。通过英国和美国地理学家学会研究组对大多数地理学系课程和学科体系的调查发现，1990年代的地理学主要由人文地理学、自然地理学、混合人文和自然地理学和其它领域四个方面所组成。 With the development of sciences and the emergence of social demands, the definition of geography has been evolving continuously. As shown in a survey about the curriculum and the subject system of geography, in the 1990s, geography was consisted of four branches: human geography, physical geography, human- physical geography together with other geography fields. 2、人文地理学的发展 Progress of human geography 18世纪后期到19世纪早期，德国和法国的人文地理学萌芽 From late 1800s to early 1900s, human geography germinated in German and France. 1918－1939，两次世界大战之间，处在早期调查阶段 From 1918 to1939, the progress of human geography was in the period of early survey. 二战后，主要从1960年代起，人文地理学与其他社会科学互动与接轨，实现了从区域描述到诠释人与社会、人与环境、及人与地点或地方关系的转变。 After the world War II, especially from the 1960s, human geography had interacted and linked up with other social sciences. It changed into interpreting the relationship between human
In the case of a resistor, the voltage-current relationship is given by Ohm’s law, which states that the voltage across the resistor is equal to the current through the resistor multiplied by the value of the resistance. 就电阻来说, 电压—电流的关系由欧姆定律决定。欧姆定律指出:电阻两端的 电压等于电阻上流过的电流乘以电阻值。 2]It may be that the inductor voltage rather than the current is the variable of interest in the circuit. 或许在电路中,人们感兴趣的变量是电感电压而不是电感电流。 Viewed in this light, it will be found that the analysis of three-phase circuits is little more difficult than that of single-phase circuits. 这样看来,三相电路的分析比单相电路的分析难不了多少。 At unity power factor, the power in a single-phase circuit is zero twice each cycle. 在功率因数为 1时,单相电路里的功率值每个周波有两次为零。 It should be noted that if the polarity of point Awith respect to N ( is assumed for the positive half-cycle, then when used in the same phasor diagram should be drawn opposite to, or 180? out of phase with, . 应该注意,如果把 A 点相对于 N 的极性(定为正半周,那么在用于同一相量图中时就应该画得同相反,即相位差为 180? One problem with electronic devices corresponding to the generalized amplifiers is that the gains, AU or AI, depend upon internal properties of the two-port system. 对应于像广义放大器这样的电子装置,一个问题就是增益 AU 或者 AI ,它们取决于两输入端系统的内部特性。
第二部分 控制理论 第1章 1.1控制系统的引入 人类控制自然力量的设计促进人类历史的发展,我们已经广泛的能利用这种量进行在人类本身力量之外的物理进程?在充满活力的20世纪中,控制系统工程的发展已经使得很多梦想成为了现实?控制系统工程队我们取得的成就贡献巨大?回首过去,控制系统工程主要的贡献在机器人,航天驾驶系统包括成功的实现航天器的软着陆,航空飞机自动驾驶与自动控制,船舶与潜水艇控制系统,水翼船?气垫船?高速铁路自动控制系统,现代铁路控制系统? 以上这些类型的控制控制系统和日常生活联系紧密,控制系统是一系列相关的原件在系统运行的基础上相互关联的构成的,此外控制系统存在无人状态下的运行,如飞机自控驾驶,汽车的巡航控制系统?对于控制系统,特别是工业控制系统,我们通常面对的是一系列的器件,自动控制是一个复合型的学科?控制工程师的工作需要具有力学,电子学,机械电子,流体力学,结构学,无料的各方面的知识?计算机在控制策略的执行中具有广泛的应用,并且控制工程的需求带动了信息技术的与软件工程的发展? 通常控制系统的范畴包括开环控制系统与闭环控制系统,两种系统的区别在于是否在系统中加入了闭环反馈装置? 开环控制系统 开环控制系统控制硬件形式很简单,图2.1描述了一个单容液位控制系统, 图2.1单容液位控制系统 我们的控制目标是保持容器的液位h 在水流出流量V 1变化的情况下保持在一定 可接受的范围内,可以通过调节入口流量V 2实现?这个系统不是精确的系统,本系 统无法精确地检测输出流量V 2,输入流量V 1以及容器液位高度?图2.2描述了这 个系统存在的输入(期望的液位)与输出(实际液位)之间的简单关系, 图2.2液位控制系统框图 这种信号流之间的物理关系的描述称为框图?箭头用来描述输入进入系统,以及