【最新】一章节基本概念Chapter1BasicConcepts
词汇学(第一章)-PPT课件
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3. Native words and borrowed words 本族语词和外来语词
Native words / Angle-Saxon words
Words of Anglo-Saxon origin are native
words. They form the great majority of the
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Another important characteristic is that function words belong to a relatively small and permanent set of words, in comparison to content words. The total number of functional words is about 154. They are stable; they do not come and go with changing fashions and ideas.
basic word stock of the English language.
The basic word stock is the foundation of the
vocabulary accumulated over a number of
epochs. Most native words in modern
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What causes the differences between sound and form?
➢ 1) More morphemes than letters, ➢ 2) Stabilization of spelling, ➢ 3) Deliberate change of spelling by
基本概念及定义
实际过程是否可以作为准静态过程来处理？ 实际过程是否可以作为准静态过程来处理？这取决于所谓 弛豫时间。 弛豫时间。 弛豫时间—气体的平衡状态被破坏后恢复平衡所需的时间 气体的平衡状态被破坏后恢复平衡所需的时间。 弛豫时间 气体的平衡状态被破坏后恢复平衡所需的时间。 大部分实际过程可以近似地当做准静态过程。 大部分实际过程可以近似地当做准静态过程。因为气体分 子热运动的平均速度可达每秒数百米以上， 子热运动的平均速度可达每秒数百米以上，气体压力传播的速 度也达每秒数百米，因而在一般工程设备具有的有限空间中， 度也达每秒数百米，因而在一般工程设备具有的有限空间中， 气体的平衡状态被破坏后恢复平衡所需的时间， 气体的平衡状态被破坏后恢复平衡所需的时间，即所谓弛豫时 间非常短。 间非常短。 例如，内燃机的活塞运动速度仅每秒十余米， 例如，内燃机的活塞运动速度仅每秒十余米，与其中的气 体分子热运动的平均速度相比相差一个数量级，因此， 体分子热运动的平均速度相比相差一个数量级，因此，当机器 工作时气体工质内部能及时地不断建立平衡状态， 工作时气体工质内部能及时地不断建立平衡状态，而工质的变 化过程很接近准静态过程
功量： 功量：
δ W = pdV
势：p 势：T
W1−2 = ∫ pdV
1
2
状态坐标: 状态坐标:V 状态坐标: ？ 状态坐标:
热量 所以有
取描述热量传递的状态坐标为熵： 单位 单位： 取描述热量传递的状态坐标为熵：S,单位：J/K。
δ Q = T dS
Q1−2 = ∫ T dS
1
2
S 工质， 对1kg工质，则有 δq = 工质 则有： = = Td = Tds m m m
对准静态过程， 对准静态过程，F=pA,所以 δW=Fdx ,所以，δ 当系统由状态1到状态2进行一个准静态过程时， 当系统由状态1到状态2进行一个准静态过程时，系统对外 界所作的功可表示为： 界所作的功可表示为： 2 2 W1− 2 = ∫ δW = ∫ pdV
Chapter 1 Basic Concepts of RC Structures
The Cubic Compressive Strength f cu （1）Definition: In GB50010-2002,the grade of
concrete is rated by the compressive strength of a
cubic specimen with side length of 150 mm, cured for 28 days under standard curing conditions(temperature is at 20℃±2℃,humidity is over 95%), tested by standard test method
Disadvantages： （1）high self-weight solution Light aggregate material
（2）Crack resistance is, work with cracks solution Prestressed concrete （3）Construction is impacted by climate conditions, the a
st = 1.2 10–5
concrete ct = 1.0 ～ 1.5 10–5 (3) Steel rebar embedded in concrete, which can prevent steel from rust.
3、 The main advantages and disadvantages of RC structures
Example: a span of 4m, a concentrated load at midspan of tested beam, beam section size is 200 ×300mm, concrete is C20. Please see:
工程力学双语chBasicConcepts
What is Mechanics?
1.1 Introduction
第4页/共19页
Mechanics is fully connected with our daily life…
Statics (静力学)Equilibrium(平衡)
1.1 Introduction
第5页/共19页
第14页/共19页
1.2-1.4 Units ant Conversion of it
Length1 in.=25.40mm1 in.=0.02540m1 ft.=0.3048mForce1 lb=4.448N1 kip=4.448kN
1mm=0.03937 in.1m=39.37 in.1m=3.281 ft1N=0.2248 lb1kN=0.2248kip
1.1 Introduction
第11页/共19页
Dose the shoe smell ok?
1.1 Introduction
第12页/共19页
1.1 Introduction
1. About Static. Static is the branch of mechanics which studies the laws of equilibrium of bodies under the action of force systems. It mainly studies simplifications and equilibrium conditions of force systems and applications of the corresponding results.2. About Strength/Mechanics of materials.3. About the study of this course.
动荷载
动载荷
10-4 构件受冲击时的应力和变形
动载荷
动载荷
动能改变：T=T 势能改变：V=Q d 弹簧应变能： Vεd 机械能守恒定律
动能 T
Q
Q
d
动能 0
T V Vεd
1 Vεd Fd d 2
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动载荷
若Q以静载的方式作用在构件上，构件有静变形和静应力为st 、△ st 在动载Fd作用在构件上，构件有动变形和动应力为d、△ d 在线弹性范围内：
Fd d d Q st st P d d Q d Fd P st , st st
1 Vεd Fd d 2
1 Q Vεd P 2 st
2 d
动载荷
T=T V=Q d
1 Vεd P Q 2 st
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2T st d 2 st d 0 d st (1 Q P
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冲击动荷因素
动载荷
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自由落体冲击问题
h
=Qh
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or
19/63
动载荷
动载荷
动载荷
若无弹簧，许可高度 为多少？
9.56mm
动载荷 例题10 图示分别为不同支承的钢梁，承受相同的重物冲
动载荷
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采矿工程英语专业词汇
采矿工程专业英语词汇手册Content目录Introduction (2)绪论 (2)Chapter 1 Basic concepts of Coal Mining (2)第一章煤矿开采的基本概念 (2)Chapter 2 Coal Mining methods (5)第二章采煤方法的概念和种类 (5)Section I Mine Field Development and Mining Design第一篇井田开拓及矿井开采设计Chapter 3 Basic Concepts of Mine Development (8)第三章井田开拓的基本概念 (8)Chapter 4 Mine Development W ays (10)第四章井田开拓方式 (10)Chapter 5 Development Roadways Layout ..... (12)第五章井田开拓巷道布置 (12)Chapter 6 Level station ….………………………………………………………..…第六章井底车场…………………………………………………….…Chapter 7 Mine Development Deepen and T echnical Reform…………………………………第七章矿井开拓延深和技术改造………………………………………….…Introduction (绪论)mine n. 矿山，矿井。
v. 采矿colliery n. 矿井coal mining 采煤underground mining 地下开采surface mining 露天开采reserve n. 储量coal-bearing adj. 含煤的high production and high efficiency 高产高效development n. 开拓preparation n. 准备mining method 采煤方法subside v. 下沉，沉陷subsidence n. 沉降，沉陷mining subsidence n. 开采沉陷mechanize v. 使…机械化mechanization n. 机械化Chapter 1 Basic Concepts of Mine (矿井基本概念)coalfield n. 煤田mining area n. 矿区mine field n. 井田divide v. 划分division n. 划分mine production capacity （MPC）矿井生产能力mine service life 矿井服务年限production scale of mine 井型small mine 小型矿井middle mine 中型矿井large mine 大型矿井huge mine 特大型矿井strike n. 走向dip n. 倾向dip angle 倾角workable adj. 可采的workable reserve n. 可采储量opening n. 通道，开口mine opening n. 矿山井巷passageway n. 通道shaft n. 立井roadway n. 巷道chamber n. 硐室main shaft 主立井auxiliary shaft 副立井air shaft 风井blind shaft 暗立井drawn shaft 溜井chute n. 溜煤眼adit n. 平硐drift n. 平硐crosscut n. 联络巷；石门coal crosscut煤门entry n. 平巷haulage n. 运输main haulage roadway 主要运输平巷main return-air roadway 主要回风平巷head entry 区段运输平巷tail entry 区段回风平巷slope n. 斜井rise n. 上山dip n. 下山rock rise 岩石上山coal rise 煤层上山coal haulage rise 运煤上山material transporting rise 运料上山return-air rise 回风上山men-walking rise 行人上山inclined roadway of a strip 分带斜巷inclined coal haulage roadway of a strip 分带运煤斜巷inclined material haulage roadway of a strip 分带运料斜巷development roadway 开拓巷道preparation roadway 准备巷道gateway 回采巷道pit bottom 井底车场shaft bottom 井底车场station n. 车场，车站mining district station 采区车场horizon n. 阶段level n. 水平haulage level 运输水平return-air level 回风水平mining level 开采水平interval between levels 阶段垂高mining district 采区panel n. 盘区sublevel n. 分段strip district n. 带区inclined length 斜长strike length 走向长度district sublevel区段Open-off cut n. 切眼coalface n. 采煤面working face工作面production n. 生产；产量production system 生产系统coal haulage system 运煤系统ventilation n. 通风ventilation system通风系统fresh air 新鲜风dirty air 乏风，污风refuse n. 矸石material and refuse transportation system 运料排矸系统drain v. 排水drainage system 排水系统power supply system (electric power, compressed air) 动力供应（电、压风）communication and monitoring system 通讯、监测系统drive v. 掘进excavate v. 开挖，开掘hoist v. 提升winch n. 绞车Chapter 2 Coal Mining methods (采煤方法)stope 采场mining works/units 回采工作basic operation 基本工序break v. 破碎load v. 装载haul v. 运输auxiliary operations 辅助工序roof support 顶板支护gob treatment 采空区处理auxiliary transportation 辅助运输ventilation 通风drainage 排水power supply 供电,emulsion supply 供液（乳化液）等。
Chapter_1__A_General_survey_of_English_vocabulary[1]
![Chapter_1__A_General_survey_of_English_vocabulary[1]](https://img.taocdn.com/s3/m/59778a25482fb4daa58d4b36.png)
Chapter 1 A General survey of English vocabulary一． Basic concepts of words and vocabulary1 - The definition of a word comprises the following points:(1) a minimal free form of a language;(2) a sound unity;(3) a unit of meaning;(4) a form that can function alone in a sentence.A word is a minimal free form of a language that has a given sound and meaning and syntactic function.2- Sound and Meaning: symbolic connection is almost always arbitrary and conventional.A dog is called a dog not because the sound and the three letters that make up the word just automatically suggest the animal in question.3- Old English, the speech of the time was represented very much more faithfully in writing than it is today. The internal reason for this is that the English alphabet was adopted from the Romans, which does not have a separate letter to represent each sound in the language so that some letters must do double duty or work together in combination.Another reason is that the pronunciation has changed more rapidly than spelling over the years, and in some cases the two have drawn far apart.A third reason is that some of the differences were created by the early scribes. Finally comes the borrowing, which is an important channel of enriching the English vocabulary.5 - Vocabulary: All the words in a language make up its vocabulary. Not only can it refer to the total number of the words in a language, but it can stand for all the words used in a particular historical period. We also use it to refer to all the words of a given dialect, a given book, a given discipline and the words possessed by an individual person. The general estimate of the present-day English vocabulary is over million words.6 - Words may fall into the basic word stock and nonbasic vocabulary by use frequency, into content words and functional words by notion, and into native words and borrowed words by origin.7 - The basic word stock is the foundation of the vocabulary accumulated over centuries and forms the common core of the language. Though words of the basic word stock constitute a small percentage of the English vocabulary, yet it is the most important part of it. These words have obvious characteristics.8 - All national character. Words of the basic word stock denote the most common things and phenomena of the world around us, which are indispensable to all the people who speak the languageNatural phenomena/Human body and relations/Names of plants and animals/Action, size, domain, state/Numerals, pronouns, prepositions, conjunctions9 - Stability. Words of the basic word stock have been in use for centuries.10 - Productivity . Words of the basic word stock are mostly root words or monosyllabic words. They can each be used alone, and at the same time can form new words with other roots and affixes.11 - Polysemy. Words belonging to the basic word stock often possess more than one meaning because most of them have undertone semantic changes in the course of use and become polysemous.12 - Collocability . Many words of the basic word stock quite a number of set expressions, idiomatic usages, proverbial sayings and the like.13 - Terminology consists of technical terms used in particular disciplines and academic areas .14 - Jargon refers to the specialized vocabularies by which members of particular arts, sciences, trades and professions communicate among themselves such as in business. 15 - Slang belongs to the sub-standard language, a category that seems to stand between the standard general words including informal ones available to everyone and in-group words like cant, jargon, and argot, all of which are associated with, or most available to, specific groups of the population.Slang is created by changing or extending the meaning of existing words though some slang words are new coinages altogether. Slang is colourful, blunt, expressive and impressive.16 - Argot generally refers to the jargon of criminals.17 - Dialectal words are words used only by speakers of the dialect in question.18 - Archaisms are words or forms that were once in common use but are now restricted only to specialized or limited use.19 - Neologisms are newly-created words or expressions, or words that have taken on new meanings.20 - By notion, words can be grouped into content words and functional words. Content words denote clear notions and thus are known as notional words. They include nouns, verbs, adjectives, adverbs and numerals, which denote objects, phenomena, action, quality, state, degree, quantity.21 - Functional words do not have notions of their own. Therefore, they are also called empty words. As their chief function is to express the relation between notions, the relation between words as well as between sentences, they are known as form words. Prepositions, conjunctions, auxiliaries and articles belong to this category.22 - However, functional words do far more work of expression in English on average than content words.23 - Native words are words brought to Britain in the fifth century by the German tribes; the Angles, the Saxons, and the Jutes, thus known as Anglo-Saxon words.24 - Apart from the characteristics mentioned of the basic word stock, in contrast to borrowed words, native words have two other features:Neutral in style. they are not stylistically specific.Stylistically, natives words are neither formal nor informal whereas the words borrowed from French or Latin are literary and learned, thus appropiate in formal style.Frequent in use. Native words are most frequently used in everyday speech and writing.25 - Words taken over from foreign languages are known as borrowed words or loan words or borrowings in simple terms. It is estimated that English borrowings constitute 80 percent of the modem English vocabulary. The English language is noted for the remarkable complexity and heterogeneity of its vocabulary because of its extensive borrowings26 - Aliens are borrowed words which have retained their original pronunciation and spelling. These words are immediately recognizable as foreign in origin.27 - Semantic-loans. Words of this category are not borrowed with reference to the form. But their meanings are borrowed. In other words, English has borrowed a new meaning for an existing word in the language.二．The development of the English vocabulary1 - It is assumed that the world has approximately 3, 000 (some put it 5, 000 ) languages, which can be grouped into roughly 300 language families on the basis of similarities in their basic word stock and grammar.2 - The Indo-European is one of them. It is made up of most of the languages of Europe, the Near East, and India.3 - They accordingly fall into eight principal groups, which can be grouped into an Eastern set: Balto-Slavic , Indo-Iranian , Armenian and Albanian ; a Western set: Celtic, Italic, Hellenic, Germanic.4 - In the Eastern set, Armenian and Albanian are each the only modern language respectively. The Balto-Slavic comprises such modern languages as Prussian, Lithuanian, Polish, Czech, Bulgarian, Slovenian and Russian.5 - In the Indo-Iranian we have Persian. Bengali, Hindi, Romany, the last three of which are derived from the dead language Sanskrit.6 - In the Western set, Greek is the modern language derived from Hellenic.7 - The Germanic family consists of the four Northern European Languages: Norwegian, Icelandic, Danish and Swedish, which are generally known as Scandinavian languages. Then there is German, Dutch, Flemish and English.8 - Old English (450-1150)Anglo-Saxon as Old English. Old English has a vocabulary of about 50, 000 to 60, 000 words. It was a highly inflected language just like moderm German.Anglo-Saxon as Old English. Old English has a vocabulary of about 50, 000 to 60, 000 words. It was a highly inflected language just like moderm German.9 - Middle English (1150-1500)Although there were borrowings from Latin, the influence on English was mainly Germanic.Between 1250 and 1500 about 9000 words of French origin poured into English. Seventy-five percent of them are still in use today.If we say that Old English was a language of full endings. Middle English was one of leveled endings.10 - Modern English (1500-up to now)Modern English began with the establishment of printing in England.Early (1500-1700) and Late (1700-up to the present) Modern EnglishIn the early period of Modern English, Europe saw a new upsurge of learning ancient Greek and Roman classics. This is known in history as the Renaissance.Latin and Greek were recognized as the languages of the We stern world’s great literary heritage and of great scholarshipIn fact, more than twenty-five per cent of modern English words come almost directly from classical languages.It can be concluded that English has evolved from a synthetic language (Old English) to the present analytic language.11 - Three main sources of new words: the rapid development of modern science and technology(45%); social, economic and politicalchanges(24%); the influence of other cultures and languages(11%).12 - Modern English vocabulary develops through three channels: creation, semantic change, borrowing.Creation refers to the formation of new words by using the existing materials, namely roots, affixes and other elements. In modern times, this is the most important way of vocabulary expansion.Semantic change means an old form which takes on a new meaning to meet the new need. This does not increase the number of word forms but create many more new usages of the words, thus enriching the vocabulary.Borrowing has played a vital role in the development of vocabulary, particularly in earlier times. Borrowed words constitute merely six to seven percent of all new worlds. In earlier stages of English, french, Greek and Scandinavian were the major contributiors.Reviving archaic or obsolete words(复活古词和废弃词) also contributes to the growth of English vocabulary though quite insignificant.。
大学英语课程 资料结构 Chapter 1 Basic Concepts
1-4
Abstract Data Type
• Native data type
– int (not realistic integer), float (real number), char – hardware implementation
Data Structures
Chapter 1: Basic Concepts
1-1
Bit and Data Type
• bit: basic unit of information. • data type: interpretation of a bit pattern. e.g. 0100 0001 integer 65 ASCII code ’A’ BCD 41 (binary coded decimal)
Recursion for Binary Search
int BinarySearch (int *a, int x, const int left, const int right) //Search a[left], ..., a[right] for x { if (left <= right) { int middle = (left + right)/2; if (x < a[middle]) return BinarySearch(a, x, left, middle-1); else if (x > a[middle]) return BinarySearch(a, x, middle+1, right); else return middle; } // end of if return -1;// not found 1-12 }
算法分析基础
6
程序(Program)
• 程序是算法用某种程序设计语言的具体实现。 • 程序可以不满足算法的有限性的性质。例如操作系统，是一个
在无限循环中执行的程序，因而不是一个算法。 • 操作系统的各种任务可看成是单独的问题，每一个问题由操作
系统中的一个子程序通过特定的算法来实现。该子程序得到输 出结果后便终止。
《算法设计技巧与分析》
第1章 算法分析基本概念
曹霑懋 caozhanmao@
Chapter 1 Basic Concepts in Algorithmic Analysis 内容
1.1 Introduction l.2 Historical Background 1.3 Binary Search 1.3.1 Analysis of the binary search algorithm 1.4 Merging Two Sorted Lists 1.5 Selectinn Sort 1.6 Insertion Sort 1.7 Bottom-Up Merge Sorting 1.7.1 Analysis of bottom-up merge sorting
最大搜索次数：满足Floor(n/2j-1)=1 时的ｊ 值
– 即：１n/2j-1 <2 – 也即： 2j-1n <2j
– j-1 log n <j
j=Floor(log n)+1
2020/6/10
华南师范大学 计算
16
设随有堂序数练组习：
试搜索x=20, 以及 X =22. 1）拟用什么法？为什么？ 2）试给出用你想要得算法求解的过程。
2020/6/10
华南师范大学 计算
14
1. 3 二分搜索及其时间复杂
Chapter1 Basic Concepts Words and Vocabulary
第一章 单词和词汇的基本概念
1.1 What Is a Word 单词是什么
1.2 Sound and Meaning 声音和意义
1.3 Sound and Form 声音和形式
1.4 Vocabulary 词汇
1.5.3 Native Words and Borrowed Words 本土词汇与外来词汇
Native words （本族语词） : known as Anglo-Saxon words (50,000-60,000), are words brought to Britain in the 5th century by the Germanic tribes. (mainstream of the basic word-stocks). 安格鲁撒克逊单词比较出名，是从5 世纪的德国部落借入英国的。 （是基础词汇的主要成分）
1.5 Classification of Words 词汇的分类
1.1 What Is a Word 单词是什么
Word（词的定义）: A word is a minimal free form of a language that has a given sound and meaning and syntactic function. 单词是语言的最小自由体，它具备一个已知的声音、意义和句法 功能。 Four points:四个特点 (1)a minimal free form of a language 语言的最小自由形式 (2)a sound unity一个声音的整体
The reasons of the difference between sound and form
Basic Concepts.ppt
Chapter One —Nature and Terminology
On the contract’s breach (a breach of contract occurs when a contractual promises is not fulfilled), the breaching party may be subject to sanctions. These sanctions may include a payment of money (damages) to the nonbreaching party for the failure to perform. Under such circumstances, the breaching party may be required to render the performance promised in the contract.
The Function of Contract
Contract law is necessary to ensure compliance with a promise or to entitle a nonbreaching party to some form of relief when a contract is breached. By providing procedures for enforcing private agreements, contract law provides an essential condition for the existence of a market economy. Without a legal framework within which to plan, businessmen would be able to rely only on the good faith of others. Duty and good faith are usually sufficient, and most contractual promises are kept simply because keeping them is in the mutual selfinterest of the promiser and the promisee. But when price changes or adverse economic factors make it costly for one of the parties to comply with a promise, duty or good faith alone may not be enough.
Chapter1BASICCONCEPTS2008
1. Land 2. Labour 3. Capital
(capital is not money assets like stocks and bonds)
4. Entrepreneur - a person who organizes the other factors of production.
• Macroeconomic
- looks at the economy as a whole on issues like employment, national income, economic growth, inflation etc.
BECON 0201 Principles of Economics
• Microeconomic
- studies the choices and decisions made by individual units of the economy (i.e. households, individuals, firms)
BECON 0201
Principles of Economics
9
Scarcity.
• The problems of what, how and for whom exist resources were limited. • Economics goods – scarce, limited & not free (FOC) • Air = non-economics goods (infinite quantities & free - air to breath) • Limited/scarce resource but unlimited human wants • needs the study economics • Scarcity = the excess of human wants over what can actually be produced, so choice have to be made between alternatives.
激光原理
玻色子Boson (自旋量子数为整数): • 光子photon (1) • 介子meson:
p, h, K & D (0) r, w (1)
•
费米子Fermion（自旋量子数为半整数）: • 轻子Lepton (1/2): 电子, m子, t子,中微子 • 重子Baryon
• •
核子：质子Protons和中子Neutron (1/2) 超子：，， (1/2)， (3/2) .
的相干度都接近于1)
定义:
Where
Vc = Ac Lc = Ac t c c
Temporal Coherence
Spatial Coherence
Ac -- 垂直于光传播方向的截面上的相干面积 Lc -- 沿传播方向的相干长度 tc = Lc /c 光沿传播方向通过相干长度L c 所需的时间---相干时间
s1 or s2
Q2.1 决定光波模式(光子态)的 特征量有哪些 ?
§1.1 Description of Light Coherence
2.1 光波的模式---模式数计算
Q2.2 在自由空间，具有任意波矢k的单
色平面波都可以存在。在各向同性的体 积V中可存在多少独立的模式?
边界限制的空间V
Dx×Dy×Dz
的相干性; 描述: 相干面积
Ac
(横向相干性)
Q3.2 如何描述光场的时间相干性/空间相干性 ?
§1.1 Description of Light Coherence
3.2 普通光源的相干性
普通光源发光-----大量原子(分子)的自发辐射. 波列的长度 Lc = c Dt , 原子(分子)发光上能级(下能级 常为基态)的寿命 Dt 与光波的相干性和光源的单色 性 有关. Dn ---- 光源单色性的量度
(最新整理)高等工程热力学英文课件：Chapter1conceptsanddefinition
Everything external to the thermodynamic system is the environment or surrounding. The exchanges of mass or energy take place between the environment and the system.
environment. The boundary can be a real/physical interface or an imaginary one. It
can be mobile or fixed. It can be rigid or deformable.
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Related concepts
(1) Working substance or working medium The medium for the inter-transformation between thermal energy and mechanical energy. Requirements: expansibility, mobility, thermal capacity, stability, safety, friendly to environment, low cost. Typical working media: combustion gas and steam. The state of working medium can be static or flowing.
5. Basic thermodynamic processes
6. Single phase systems
basic
z × ² ½ 7.¸ ® À ª ê Ƥ R 3.§ ¦ ° ³ Î ¨ ² ]
6.¸ ® ¦ ¶ ê Ƭ ° 5.¿ ¶ ¤ ¨ Åq u ã
14
主要的量化研究方法
调查法
樣本選擇(又稱為抽樣方法)成為調查法研究 的重要工作。調查法的樣本必須具有隨機性、 代表性與足夠大小。 形式上分为结构性与非结构性问题。 内容分为事实性与态度性问题。
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主要的量化研究方法
相关研究法(Correlational research)
讨论两个或多个变项之 间关联性之方法 关联性之强度可以藉由相关系数来表示，正 相关代表变项间具有相同之变动方向，负相 关代表变项间变动方向相反。 此类研究仅能说明变项间之相关性，无法推 断因果关系与影响方向。因此有时需进行预 测或因果性分析(如回归分析或路径分析等)
测量的尺度（方法）
由测量尺度区分变项： 1. 名义变项(nominal)或类别变项(categorical)：将对 象分类为间断类别，以属性来辨识或表示事物类别， 如年龄、种族、婚姻状况等。 2. 次序变项(ordinal variable) ：变项除具有分类特 性外，又具备等级排序关系。主要属性在于表示对象 间优劣、多少、高低、次序等，如教育程度变项：研 究所以上、大学、专科、高中职以下等四种水平。 3. 等距变项(interval variable)：针对被观察者之某 种现象或特质，依特定之标准化单位测定程度上的特 性。
假设乃是在描述变项与变项之间的关系 研究者对于待解决之问题所提出之暂时的或尝试的答 案
chapter 1 basic amplifier concepts
overview of electronic system and steps of design process, basic concepts Amplifier: concepts and application Operational amplifiers: the ideal operational amplifier and op-amp imperfections in the linear range of operation Feedback :principle and design of feedback amplifiers Active filters: Low-pass filters, High-pass filters, band-pass filter, and band-stop filter
The Voltage Amplifier Model
Amplification can be modeled by a controlled source as illustrated in Figure below.
The input resistance Ri
Output resistance Ro
The Voltage Amplifier Model
The
input resistance Ri of an amplifier is the equivalent resistance seen when looking into the input terminals. Output resistance Ro is the Thevenin resistance seen when looking back into the output terminals of an amplifier.
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表压力：当高于大气压时，压力计显示的绝对压力 超出大气压力的部分。
Gage pressure（表压力）is denoted as Pg
表压力=绝对压力-大气压力 真空度表示绝对压力低于大气压力的量值
Vacuum pressure （真空度）：Pressures below atmosphere pressure. It is the pressure difference between atmospheric and system pressure when system pressure is lower than atmospheric And it is denoted as PVAC or H. 真空度=大气压力-绝对压力
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§1.1 热力系统 Thermodynamic System
1. 热力系统的定义（Definition ）
系统就是指被选做研究对象的物体或空间。 （A quantity of matter or a region in space
chosen for study.）
For example:
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(4) Characteristics of Boundary
▪ 边界是人为选定的 Boundaries are selected subjectively.
边界可以是固定的，也可以是可移动的 Boundaries can be fixed or movable.
边界可以是真实的，也可以是假想的 Boundaries can be real or imaginary.
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63.热力系统分ຫໍສະໝຸດ Types of systems
热力系
物质流进和流 出热力系统
物质交换 能量交换
外界
传热和作功两 种形式
Energy can cross the boundary, in the
form 2021/2/2 of heat and work.
7
(1) 以系统与外界关系划分：
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（2）状态参数的特征 Characteristics of State Properties
A. 状态确定，则状态参数也确定，反之亦然 Properties of a state are determined by the state.
If the state is specified, its properties are fixed, or vise versa.
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热力系统选取的人为性
锅 炉 boiler
过热器 (reheater)
汽轮机(turbine)
发电机(generator) 凝汽器
(condenser)
只交换功 既交换功 也交换热
只交换热
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给水泵(pump)
固定、活动
fixed 、 movable
真实、虚构
real 、 imaginary
是否传质 是否传热 是否传功 是否传热、功、质
有 开口系 非绝热系 非绝功系 非孤立系
无 闭口系 绝热系 绝功系 孤立系
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A. 闭口系统和开口系统 Closed system and Open system
闭口系与外界无物质交换
A Closed system (a control mass 控制质量) consists of a fixed amount of mass, and no mass can cross its boundary. That is, no mass enters or leave a closed system.
It has the unit of Newtons per square meter （N/m2)
1 Pa=1 N/m2
1 kPa= 103 Pa
1 MPa= 106 Pa
SI单位制
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其他单位 Other units
1 bar =105 Pa=100 kPa =0.1 MPa 标准大气压 Standard atmosphere
such as, A Water heater, a turbine and a compressor, etc
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B. 绝热系统和孤立系统 Adiabatic system and Isolated system
绝热系统与外界之间无热量交换 Adiabatic system is that no heat cross the boundary or heat is negligible compared with work cross the boundary
（2）边界（Boundary） The real or imaginary surface that separates the system from its surroundings.
(3) 系统与外界之间的质量及能量交换都必须穿越边界 The mass or energy exchange between system and its surroundings must cross the boundaries.
B. 状态参数的积分特征：状态参数的变化量与路径无关，只 与初终态有关
The magnitude of the change in property is independent of
the path (route), but just depend on the initial and final states.
1 atm= 101325 Pa=101.325 kPa 工程大气压 Engineer atmosphere
1 at=1 kgf/cm2 =9.807 N/cm2 =9.807*104 Pa
液柱高度 Height of liquid column 1 atm=760 mm Hg
1 at =10 m H2O
气缸-活塞装置
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Cylinder-piston equipment
汽轮机Steam turbine
2
2. 系统，外界和边界 System, Surroundings and boundary
(1) 外界（Surroundings） The mass or region outside the system
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2. Property （状态参数）
（1）状态参数：描述系统宏观物理状况的物理量,简称参数 Properties are used to depict any characteristic of a system.
such as
Pressure P （压力），temperature T（温度）， volume V（体积），mass m（质量）， internal energy U（内能），enthalpy（焓）， entropy（熵）， viscosity（粘度）， thermal conductivity（导热系数）。
3
非孤立系＋相关外界
＝孤立系
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（2）其它分类方式
物理化学性质
均匀系（Even System)
非均匀系(Uneven System)
其它分类方式
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工质种类
单元系 (Single substance system)
相态
多元系(multi substance system) 单相 (Single Phase)
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§1.2状态及状态参数 State and State Properties
1. 状态：某一瞬间热力系所呈现的宏观状况 State: it reveals the physical condition of a system.
Consider a system not undergoing any change. At this point, all the properties can be measured or calculated throughout the entire system. It can be described by a set of properties
多相(Multiple Phase) 13
简单可压缩系统 Simple compressible system 最重要的系统 只交换热量和一种准静态的容积变化功
Moving Boundary Work 容积变化功 Compression Work
压缩功 膨胀功
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Expansion Work
压力 p、温度 T、比容 v （容易测量）
(1)密度和比容
Density and Specific Volume
密度指单位体积所含物质的多少。
Density is defined as mass per unit
volume.
m
V
kg/ m3
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比体积
单位质量的物质所占有的体积，用v表示。
第一章 基本概念 Chapter 1. Basic Concepts
➢ 热力系统（Thermodynamic System） ➢ 系统的状态参数（Properties of A System） ➢ 状态及平衡状态（State and Equilibrium） ➢ 过程与循环（Process and Cycles）
It is defined as the force exerted by a fluid vertically on a surface of unit area.