chapter03
环境经济学Chapter_03
生产率变动法
又称生产效应法，环境变化可以通过生
产过程影响生产者的产量、成本和利润， 或是通过消费品的供给与价格变动影响 消费者福利 估计环境变化对受体（财产、设备或者 人）影响的物理效果和范围 评估对成本或产出造成的影响 评价产出或者成本变化的经济价值
估算保护自然资源的机会成本，用该资
源作为其他用途时可能获得的收益表征
估算资源保护的机会成本，让决策者和
公众决定自然资源是否具有价值或是否 值得为保护资源而放弃这些收益
计算由于环境污染引起的经济损失
©中国人民大学环境学院 2004-2012
直接市场评价法适用于：
水土流失对农业的影响 泥沙沉积对下游使用者的影响
©中国人民大学环境学院 2004-2012
与环境相关的外部性，主要是生产
和消费的外部不经济性，尤其是生 产的外部不经济性，并且都不是货
币外部性。
©中国人民大学环境学院 2004-2012
环境外部性对资源配置影响
外部性是当一个行动的某些效益或费用不在
决策者的考虑范围内所产生的一种低效率,将 导致市场失灵 外部性计量:社会成本或效益与私人成本或效 益之间的差值
生产力
健康影响
舒适性
旅行费用法 内涵资产价值法 意愿调查价值评估法
环境经济评价的含义
定量评估环境资源提供的物品或服务的
经济价值（货币形式），衡量人们对环 境物品或服务的偏好程度。 环境经济评价为制定环境政策提供了依 据，将环境影响纳入综合决策过程的重 要步骤 完整测度人类社会经济活动的费用和效 益
第三章
环境价值与外部性
环境资源的价值
价值的形成与实现
chapter03外汇业务和汇率折算ppt课件
4
三、外汇市场的类型：
1、批发市场、零售市 场；
2、柜台市场和交易所 市场
3、官方外汇市场、自 由外汇市场和外汇 黑市；
同意 我的日元请划拨至B 银行账号为+++ 谢谢你朋友，再见
11
二、 期汇交易（远期外汇交易）
1）远期外汇交易概述 （1）含义：交易货币的交割在2个工作日以
后进行，期限以1－3个月居多，最长可以 做到1年。 （2）使用远期汇率(forward exchange rate)
由双方在远期合约成交时确定下来 是约定日期交割约定金额货币的价格依据
2)即期外汇交易的基本程序
询价→ 报价→成交→证实→结算
3)即期外汇交易的报价 （1）采用美元报价 （2）采用双向报价 （3）使用规范用语 （4）通过电话、电传等报价时，报价银行一
般只报汇率的最后两位数。
9
即期汇率报价
BCGD：GTCX SP JPY
香港中银请报美元兑日元的即期汇价
GTCX：115.70/80
（2）若远期汇率的报价小数在前，大数在后，则表示单位货币 远期升水，计算时应用即期汇率价加上远期点数。
13
直接标价法:
远期汇率=即期汇率+升水 -贴水
如:某日纽约外汇市场的即期汇率为:1欧元=1.2481美元,3 个月欧元远期外汇升水0.32美分,则3个月欧元远期外 汇汇率为: 1欧元=1.2481+0.0032=1.2513美元 如果3个月欧元远期外汇贴水0.32美分,则3个月欧元远 期外汇汇率为: 1欧元=1.2481-0.0032=1.2449美元
Chapter03旋转机械故障诊断mfd,故障诊断,电子科技大学ppt课件
n0 .5 n cr 1
刚性转子
0 . 5 n n 0 . 7 n cr 1 cr 1
准刚性转子 柔性转子
n0 .7 n cr 1
机械电子工程学院
3.1.2.2 阻尼对临界转速下转子振动的影响
取坐标系Oxy，在x和y两坐标方向上列力的平衡式：
2 m x c x kx me cos t 2 m y c y ky me sin t
3.1.2.1 临界转速的动力特性
一般规定，转子在一阶临界转速以下运行时，工作转速n应低 n cr 0.75 于一阶临界转速 的 倍；工作转速高于一阶临界转速时， 1 要求在下列范围内（i为临界转速的阶数）：
1 . 4 n n 0 . 7 n cri cr ( i 1 )
从动力学角度分析，转子系统分为刚性转子和柔性转子。 转动频率低于转子一阶横向固有频率的转子为刚性转子，如 电动机、中小型离心式风机等。转动频率高于转子一阶横向固 有频率的转子为柔性转子，如燃气轮机转子。
2 2
A
2 2 n
2
式中阻尼比为：
c 2mn
2 n arctan 2 1 n
机械电子工程学院
3.1.2.2 阻尼对临界转速下转子振动的影响
机械电子工程学院
3.1.2 临界转速对不平衡振动的影响
3.1.2.1 临界转速的动力特性
在工程上，把对应于转子一阶横向固有频率的转速称为临界 转速。 临界转速是指由不平衡离心力引起转子共振现象时的转速。
转子运动的力学模型
机械电子工程学院
3.1.2.1 临界转速的动力特性
茶树育种学Chapter-03第三章 选择育种
江山千秋俊 是却未必有利于茶树本身对环境条件的适应性，
如果按单一的经济目标进行多世代人工选择，会
昌隆万代兴 导致原有种群的遗传基础变窄，抗性基因就有可
能“丢失”。
第二节 选择与选择育种
二、 遗传力与选择效果
（一）遗传力的概念
江山千秋俊 表型变异:基因及相互作用+环境作用
第二节 选择与选择育种
无意识选择是指人类无预定目标地保存优良 个体，淘汰没有价值的个体。作用一般比较缓慢，
江山千秋俊 但随着时间的积累也会产生明显的效果。 昌隆万代兴 有意识选择是指有目标、有计划，应用完善
的鉴定方法系统地进行工作。这种选择作用大， 见效快，现在主要是有意识选择。
第二节 选Байду номын сангаас与选择育种
→龙井43；祁门群体→安徽1、3、7号 。 （2）连续选优，品种不断改进提高
变异→选择→变异→选择
在长期的自然选择和人工选择下，品种 资源形成了非常丰富的多样性。选择育种简单
江山千秋俊 易行的育种方法，初期很多品种大都用这种方 昌隆万代兴 法育成。选择育种不仅用于从有性品种中分离
选择新品种，而且也用于引种后的驯化选择、 杂交育种Ｆ1的分离选择、人工诱变材料的选 择等。
（1）自然异交引起的基因重组 茶树是异花授粉植物，在繁殖过程中不可避免
江山千秋俊 地会发生异交，每一次有性繁殖都要伴随基因重组 昌隆万代兴 而发生性状的改变。基因重组是有性群体前后代及
同代不同个体间的遗传变异的主要来源，但群体的 遗传变异还主要受选择的影响，通过逐代选择，使 群体内的基因型频率和基因频率向选择方向变化。
第三节 选择的类别
二、单株选择、集团选择和混合选择 （1）单株选择法：从原始群体中选 取优良单株，分别编号，分别繁殖，
(国际经济学课件)chapter03The Ricardian Model
partial equilibrium analysis
opportunity cost
nontraded goods production possibility frontier
pauper labor argument
unit labor requirement
relative supply/demand curve
(ⅳ)Trade in a one-factor world
PC/PW
a *LC/a*LW
RS
a LC/aLW
RD
2021/1/13
(L/aLC)/(L*/a*LW) (QC+Q*C)/(QW+Q*W)
1.PC/PW< aLC/aLW < a*LC /a*LW
The supply of cheese equals to zero.
2021/1/13
据经济之声《天下财经》报道，美国经济和政策研究 中心主任德安·贝克尔介绍，在中国，工人的工资大约为 每小时2到3美元，几年前则为不到1美元。而在美国，大 约每小时为18到20美元。中美制造业工资水平相差9倍， 但是未来差距将缩小。
2021/1/13
Main Contents:
• Introduction • The Concept of Comparative Advantage • A One-Factor Economy • Trade in a One-Factor World • Comparative Advantage with Many Goods • Adding Transport Costs and Nontraded
LNG液化天然气Chapter03气液相平衡
Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
液 固 固 液 固 临界点 气
液
临界点 气
汽 汽
由一系列面组成，表示单相或由两相组成的混合相。
College of Chemistry & Chemical Engineering,SWPU 10
Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
6、饱和蒸汽压(Vapor Pressure) 在一定T下，液体与在液面上的蒸气呈 平衡状态时，此蒸气所产生的压力。 体现为气相分子对器壁的压力。 7、沸点(Boiling Point) 蒸汽 液体
形状与容器底部相同，难于被压缩，仅在极高压力下 可被压缩。 (3)固相(Solid Phase) 有固定形状而不能被压缩。
可能存在几种液相和固相，但气相只有一种。天然气
处理与加工中通常只需考虑液相和气相。
College of Chemistry & Chemical Engineering,SWPU 5
Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
将三维立体相图进行的投影可得到二维平面相图。
College of Chemistry & Chemical Engineering,SWPU
11
Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
泡点温度：在p一定的时，开始从液相中出现第一个
国际商务PPTChapter03
and network of interpersonal contacts; competition between individuals less ability to build
teams to perform collective tasks.
3-14
Individuals And Groups
There may be a relationship between the culture and the cost of doing business in a country or region.
Culture is not static. – MNEs can contribute to cultural change. (Western fast-food companies)
While all societies are stratified to some extent, they differ by: the degree of mobility between social strata the significance attached to social strata in business
Societies differ in terms of the degree to which the group is viewed as the primary means of social organization.
怀尔德会计学原理答案Chapter-03
Chapter 3Adjusting Accounts and Preparing1. The cash basis of accounting reports revenues when cash is received while theaccrual basis reports revenues when they are earned. The cash basis reports expenses when cash is paid while the accrual basis reports expenses when they are incurred and matched with revenues they generated.2. The accrual basis of accounting generally provides a better indication of companyperformance and financial condition than does the cash basis. Also, the accrual basis increases the comparability of financial statements from one period to the next.Thus, business decision makers generally prefer the accrual basis.3. Businesses that have major seasonal variations in sales are most likely to select thenatural business year as the fiscal year.4. A prepaid expense is an item paid for in advance of receiving its benefits. As such, itis reported as an asset on the balance sheet.5. Long-term tangible plant assets such as equipment, buildings, and machinery leadto adjustments for depreciation. Generally, land is the only long-term tangible plant asset that does not require depreciation.6. The Accumulated Depreciation contra account is used for depreciation. It providesfinancial statement users with additional information about the relative age of the assets. Without the contra account information, the reader would not be able to tell whether the assets are new or in need of replacement.7. Unearned revenue refers to cash received in advance of providing products andservices. Another name for unearned revenue is deferred revenue. It is reported asa liability on the balance sheet.8. Accrued revenue is revenue that is earned but is not yet received in cash (and/orother assets) and the customer has not been billed prior to the end of the period.Therefore, end-of-period adjustments are made to record accrued revenue.Examples are interest income that has been earned but not collected and revenues from services performed that are neither collected nor billed.9.A If prepaid expenses are initially recorded with debits to expense accounts, then theprepaid expenses asset accounts are debited in the adjusting entries.10. For Best Buy, all of the accounts under the category of Property and Equipment(except for Land), require adjusting entries. The expense related to the depreciation expense account would be understated on the income statement if Best Buy fails to adjust these asset accounts. If the adjusting entries are not made, net income would be overstated. Note: Students might also correctly identify accounts receivable, goodwill, and tradenames as needing adjustment.11. Circuit City must make adjusting entries to Prepaid expenses and other currentassets; Deferred income taxes; Accrued expenses and other current liabilities;Accrued income taxes; and possibly other assets and liabilities such as Receivables for bad debts. (It is also possible that Circuit City would need to adjust Goodwill and Other intangible assets.)12. RadioShack would need to debit interest receivable and credit interest revenue.13. The Accrued Wages Expense would be reported as part of “Accrued Expenses” onCash AccountingRevenues (cash receipts) ...................................................... $52,000Expenses (cash payments: $37,500 - $6,000 + $3,250) ...... 34,750Net income ............................................................................. $17,250 Accrual AccountingRevenues (earned) ................................................................ $60,000Expenses (incurred) .............................................................. 37,500Net income .............................................................................. $22,500 Quick Study 3-2 (10 minutes)a. AE Accrued expensesb. PE Prepaid expensesc. UR Unearned revenuesd. PE Prepaid expenses (Depreciation)e. AR Accrued revenuesa. Debit Unearned Revenue Balance SheetCredit Revenue Earned Income Statementb. Debit Wages Expense Income StatementCredit Wages Payable Balance Sheetc. Debit Accounts Receivable Balance SheetCredit Revenue Earned Income Statementd. Debit Insurance Expense Income StatementCredit Prepaid Insurance Balance Sheete. Debit Depreciation Expense Income StatementCredit Accumulated Depreciation Balance SheetQuick Study 3-4 (15 minutes)a. Insurance Expense ....................................................... 3,000Prepaid Insurance ................................................. 3,000 To record 6-month insurance coverage expired.b. Supplies Expense ......................................................... 4,150Supplies .................................................................. 4,150 To record supplies used during the year.($900 + $4,000 – [?] = $750)Quick Study 3-5 (15 minutes)a. Depreciation Expense—Equipment ............................ 8,400Accumulated Depreciation—Equipment ............. 8,400 To record depreciation expense for the year.($45,000 - $3,000) / 5 years = $8,400b. No depreciation adjustments are made for land asit is expected to last indefinitely.Salaries Expense (400)Salaries Payable (400)To record salaries incurred but not yet paid.[One student earns $100 x 4 days, Mondaythrough Thursday]Quick Study 3-7 (15 minutes)a. Unearned Revenue ........................................................ 22,500Legal Revenue ....................................................... 22,500 To recognize legal revenue earned (30,000 x 3/4).b. Unearned Subscription Revenue ................................ 1,200Subscription Revenue ........................................... 1,200 To recognize subscription revenue earned.[100 x ($24 / 12 months) x 6 months]1. Accrue salaries expense e ga f2. Adjust the Unearned Services Revenue accountto recognize earned revenueb f3. Record the earning of services revenue for whichcash will be received the following periodQuick Study 3-9 (10 minutes)The answer is a.ExplanationThe debit balance in Prepaid Insurance was reduced by $400, implying a $400 debit to Insurance Expense. The credit balance in Interest Payable increased by $800, implying an $800 debit to Interest Expense.The answer is 2.ExplanationInsurance premium errorUnderstates expenses (and overstates assets) by .......... $1,600 Accrued salaries errorUnderstates expenses (and understates liabilities) by .... 1,000The collective effects from this company’s errors follow:Understates expenses by ..................................................... $2,600Overstates assets by ............................................................. $1,600Understates liabilities by ...................................................... $1,000 Quick Study 3-11 (10 minutes)Profit margin = $78,750 / $630,000 = 12.5%Interpretation: For each dollar that records as revenue, it earns 12.5 cents in net income. Miller’s 12.5% is markedly lower than competitors’ average profit margin of 15%—it must improve performance.Quick Study 3-12A (5 minutes)1. B 4. A2. F 5. D3. C 6. EExercise 3-2 (25 minutes)a. Depreciation Expense—Equipment ................................ 16,000Accumulated Depreciation—Equipment..................... 16,000 To record depreciation expense for the year.b. Insurance Expense ........................................................... 5,360Prepaid Insurance* ....................................................... 5,360 To record insurance coverage that expired($6,000 - $640).c. Office Supplies Expense .................................................. 3,422Office Supplies**............................................................ 3,422 To record office supplies used ($325 + $3,480 - $383).d. Unearned Fee Revenue .................................................... 3,000Fee Revenue .................................................................. 3,000 To record earned portion of fee received in advance($15,000 x 1/5).e. Insurance Expense ........................................................... 6,160Prepaid Insurance ......................................................... 6,160 To record insurance coverage that expired.f. Wages Expense ................................................................. 2,700Wages Payable .............................................................. 2,700 To record wages accrued but not yet paid.a. Unearned Fee Revenue .................................................... 5,000Fee Revenue .................................................................. 5,000 To record earned portion of fee received in advance($15,000 x 1/3).b. Wages Expense ................................................................. 7,500Wages Payable .............................................................. 7,500 To record wages accrued but not yet paid.c. Depreciation Expense—Equipment ................................ 17,251Accumulated Depreciation—Equipment..................... 17,251 To record depreciation expense for the year.d. Office Supplies Expense .................................................. 5,682Office Supplies*............................................................. 5,682 To record office supplies used ($240 + $6,102 - $660).e. Insurance Expense ........................................................... 2,700Prepaid Insurance†........................................................ 2,700 To record insurance coverage expired ($4,000 - $1,300).f. Interest Receivable ......................................................... 1,400Interest Revenue ........................................................ 1,400 To record interest earned but not yet received.g. Interest Expense ............................................................. 2,000Interest Payable........................................................... 2,000 To record interest incurred but not yet paid.a. Adjusting entry2009Dec. 31 Wages Expense (825)Wages Payable (825)To record accrued wages for one day.(5 workers x $165)b. Payday entry2010Jan. 4 Wages Expense.......................................................2,475Wages Payable (825)Cash .....................................................................3,300To record accrued and current wages.Wages expense = 5 workers x 3 days x $165Cash = 5 workers x 4 days x $165Exercise 3-5 (15 minutes)a. $ 2,000b. $ 6,607c. $11,987d. $ 1,375Proof: (a) (b) (c) (d) Supplies available – prior year-end ......... $ 350 $1,855 $ 1,576 $1,375 Supplies purchased in current year ........ 2,450 6,307 11,987 6,907 Total supplies available ............................ 2,800 8,162 13,563 8,282 Supplies available – current year-end ..... (800) (6,607) (2,056) (800) Supplies expense for current year........... $2,000 $1,555 $11,507 $7,482a.Apr. 30 Legal Fees Expense ........................................... 4,500Legal Fees Payable ..................................... 4,500 To record accrued legal fees.May 12 Legal Fees Payable ............................................ 4,500Cash ............................................................. 4,500 To pay accrued legal fees.b.Apr. 30 Interest Expense ................................................. 1,900Interest Payable .......................................... 1,900 To record accrued interest expense($5,700 x 10/30).May 20 Interest Payable .................................................. 1,900Interest Expense ................................................. 3,800Cash ............................................................. 5,700 To record payment of accrued and currentinterest expense ($5,700 x 20/30).c.Apr. 30 Salaries Expense ................................................ 4,800Salaries Payable.......................................... 4,800 To record accrued salaries($12,000 x 2/5 week).May 3 Salaries Payable ................................................. 4,800Salaries Expense ................................................ 7,200Cash ............................................................. 12,000 To record payment of accrued andcurrent salaries ($12,000 x 3/5 week).Basis*Basis Basis**Basis Dec. 31, 2007 ........$14,450 $0 2007 ..........$ 850 $15,300 Dec. 31, 2008 ........9,350 0 2008 ..........5,100 0 Dec. 31, 2009 ........4,250 0 2009 .......... 5,100 0 Dec. 31, 2010 ........0 0 2010 .......... 4,250 0$15,300 $15,300 Explanations:*Accrual asset balance equals months left in the policy x $425 per month (monthly cost is computed as $15,300 / 36 months).Months Left Balance12/31/2007 .. 34 $14,45012/31/2008 .. 22 9,35012/31/2009 .. 10 4,25012/31/2010 .. 0 0**Accrual insurance expense equals months covered in the year x $425 per month.Months Covered Expense2007 ............ 2 $ 8502008 ............12 5,1002009 ............12 5,1002010 ............10 4,250$15,300Dec. 31 Accounts Receivable ............................................. 1,980Fees Earned ..................................................... 1,980 To record earned but unbilled fees (30% x $6,600).31 Unearned Fees ........................................................ 4,620Fees Earned ..................................................... 4,620 To record earned fees collected in advance(70% x $6,600).31 Depreciation Expense—Computers ..................... 1,650Accumulated Depreciation-Computers ........ 1,650 To record depreciation on computers.31 Depreciation Expense—Office Furniture ............. . 1,925A ccumulated Depreciation—Office Furniture ... 1,925To record depreciation on office furniture.31 Salaries Expense .................................................... 2,695Salaries Payable.............................................. 2,695 To record accrued salaries.31 Insurance Expense.................................................. 1,430Prepaid Insurance ........................................... 1,430 To record expired prepaid insurance.31 Rent Expense (700)Rent Payable (700)To record accrued rent expense.31 Office Supplies Expense (528)Office Supplies (528)To record use of office supplies.31 Advertising Expense (500)Advertising Payable (500)To record accrued advertising expense.31 Utilities Expense (77)Utilities Payable (77)To record incurred and unpaid utility costs.a. $ 6,039 / $ 52,970 = 11.4%b. $100,890 / $ 471,430 = 21.4%c. $106,880 / $ 301,920 = 35.4%d. $ 67,140 / $1,721,520 = 3.9%e. $ 84,780 / $ 513,800 = 16.5%Analysis and Interpretation: Company c has the highest profitability according to the profit margin ratio. Company c earns 35.4 cents in net income for every one dollar of net sales earned.Exercise 3-10A (30 minutes)a.Dec. 1 Supplies Expense ................................................... 2,000Cash ................................................................. 2,000 Purchased supplies.b.Dec. 2 Insurance Expense ................................................. 1,540Cash ................................................................. 1,540 Paid insurance premiums.c.Dec. 15 Cash ......................................................................... 13,000Remodeling Fees Earned ............................... 13,000 Received fees for work to be done.d.Dec. 28 Cash ......................................................................... 3,700Remodeling Fees Earned ............................... 3,700 Received fees for work to be done.e.Dec. 31 Supplies .................................................................. 1,840Supplies Expense ........................................... 1,840 Adjust expenses for unused supplies.f.Dec. 31 Prepaid Insurance .................................................. 1,200Insurance Expense ......................................... 1,200 Adjust expenses for unexpired coverage($1,540 - $340).g.Dec. 31 Remodeling Fees Earned ..................................... 11,130Unearned Remodeling Fees .......................... 11,130 Adjusted revenues for unfinished projects($13,000 + 3,700 - $5,570).a. Initial credit recorded in the Unearned Fees accountJuly 1 Cash ....................................................................... 2,800Unearned Fees .............................................. 2,800 Received fees for work to be done for Solana.6 Cash ....................................................................... 8,100Unearned Fees .............................................. 8,100 Received fees for work to be done for Haru.12 Unearned Fees ...................................................... 2,800Fees Earned ................................................... 2,800 Completed work for Solana.18 Cash ....................................................................... 7,300Unearned Fees .............................................. 7,300 Received fees for work to be done for Jordan.27 Unearned Fees ...................................................... 8,100Fees Earned ................................................... 8,100 Completed work for customer Haru.31 No adjusting entries required.b. Initial credit recorded in the Fees Earned accountJuly 1 Cash ....................................................................... 2,800Fees Earned ................................................... 2,800 Received fees for work to be done for Solana.6 Cash ....................................................................... 8,100Fees Earned ................................................... 8,100 Received fees for work to be done for Haru.12 No entry required.18 Cash ....................................................................... 7,300Fees Earned ................................................... 7,300 Received fees for work to be done for Jordan.27 No entry required.31 Fees Earned .......................................................... 7,300Unearned Fees .............................................. 7,300 Adjusted to reflect unearned fees for unfinishedjob for Jordan.c. Under the first method (and using entries from a)Unearned Fees = $2,800 + $8,100 - $2,800 + $7,300 - $8,100 = $7,300 Fees Earned = $2,800 + $8,100 = $10,900Unearned Fees = $7,300Fees Earned = $2,800 + $8,100 + $7,300 - $7,300 = $10,9001. I 5. G 9. H2. D 6. C 10. E3. F 7. I 11. H4. B 8. A 12. BProblem 3-2A (35 minutes)Part 1Adjustment (a)Dec. 31 Office Supplies Expense ................................ 12,325Office Supplies ......................................... 12,325 To record cost of supplies used($2,900 + $11,977 - $2,552).Adjustment (b)31 Insurance Expense .......................................... 12,280Prepaid Insurance .................................... 12,280B 290 ($10,440/36 mo.) 9 2,610C 770 ($ 9,240 /12 mo.) 5 3,850Total $12,280Adjustment (c)31 Salaries Expense ............................................. 3,660Salaries Payable....................................... 3,660 To record accrued but unpaid wages(2 days x $1,830).Adjustment (d)Dec. 31 Depreciation Expense—Building ................... 18,875Accumulated Depreciation—Building ... 18,875 To record annual depreciation expense[($800,000 -$45,000) / 40 years = $18,875]Adjustment (e)31 Rent Receivable ............................................ 3,000Rent Earned ........................................... 3,000 To record earned but unpaid Dec. rent.Adjustment (f)31 Unearned Rent .............................................. 5,436Rent Earned ........................................... 5,436 To record the amount of rent earned forNovember and December (2 x $2,718).Part 2Cash Payment for (c)Jan. 6 Salaries Payable ........................................... 3,660Salaries Expense* ........................................ 5,490Cash ....................................................... 9,150 To record payment of accrued andcurrent salaries. *(3 days x $1,830)Cash Payment for (e)15Cash ............................................................... 6,000Rent Receivable .................................... 3,000Rent Earned ........................................... 3,000 To record past due rent for two months.Part 2Adjustment (a)Dec. 31 Insurance Expense ...............................................3,000Prepaid Insurance ...........................................3,000 To record the insurance expired.Adjustment (b)31 Teaching Supplies Expense ................................9,000Teaching Supplies ..........................................9,000 To record supplies used ($11,000 - $2,000).Adjustment (c)31 Depreciation Expense—Equipment ....................10,000Accumulated Depreciation—Equipment ............10,000 To record equipment depreciation.Adjustment (d)31 Depreciation Expense—Profess. Library ...........5,000A ccumul. Depreciation—Profess. Library.........5,000To record professional library depreciation.Adjustment (e)31 Unearned Training Fees .......................................5,000Training Fees Earned .....................................5,000 To record 2 months’ training fees earnedthat were collected in advance.Adjustment (f)31 Accounts Receivable ............................................4,000Tuition Fees Earned........................................4,000 To record tuition earned($1,600 x 2 1/2 months).Adjustment (g)31 Salaries Expense (480)Salaries Payable (480)To record accrued salaries(2 days x $120 x 2 employees).Adjustment (h)31 Rent Expense ........................................................2,178Prepaid Rent ....................................................2,178 To record expiration of prepaid rent.Part 3WELLS TEACHING INSTITUTEAdjusted Trial BalanceDecember 31, 2009Debit Credit Cash .......................................................................... $ 28,064Accounts receivable ................................................ 4,000Teaching supplies ................................................... 2,000Prepaid insurance .................................................... 13,000Prepaid rent 0Professional library ................................................. 33,000 Accumulated depreciation—Professional library ... $ 15,000 Equipment ................................................................ 75,800 Accumulated depreciation—Equipment ................ 25,000 Accounts payable .................................................... 39,500 Salaries payable . (480)Unearned training fees ............................................ 7,500 T. Wells, Capital ....................................................... 71,000 T. Wells, Withdrawals .............................................. 44,000Tuition fees earned .................................................. 115,000 Training fees earned ................................................ 46,000 Depreciation expense—Professional library ........ 5,000 Depreciation expense—Equipment ....................... 10,000Salaries expense ..................................................... 52,480Insurance expense................................................... 3,000Rent expense ............................................................ 26,136Teaching supplies expense .................................... 9,000 Advertising expense ................................................ 8,000Utilities expense....................................................... 6,000 _______ Totals ........................................................................ $319,480 $319,480Part 4WELLS TEACHING INSTITUTEIncome StatementFor Year Ended December 31, 2009RevenuesTuition fees earned ............................................ $115,000Training fees earned .......................................... 46,000Total revenues .................................................... $161,000 ExpensesDepreciation expense—Professional library ... 5,000Depreciation expense—Equipment .................. 10,000Salaries expense ................................................ 52,480Insurance expense ............................................. 3,000Rent expense ...................................................... 26,136Teaching supplies expense ............................... 9,000Advertising expense .......................................... 8,000Utilities expense ................................................. 6,000Total expenses ................................................... 119,616 Net income ............................................................ $ 41,384WELLS TEACHING INSTITUTEStatement of Owner’s EquityFor Year Ended December 31, 2009T. Wells, Capital, December 31, 2008 ................................. $ 71,000 Plus: Net income .................................................................. 41,384112,384 Less: Withdrawals by owner ............................................... 44,000 T. Wells, Capital, December 31, 2009 ................................. $ 68,384Problem 3-3A (Concluded)WELLS TEACHING INSTITUTEBalance SheetDecember 31, 2009AssetsCash ................................................................................. $ 28,064 Accounts receivable ...................................................... 4,000 Teaching supplies .......................................................... 2,000 Prepaid insurance .......................................................... 13,000 Professional library ........................................................ $33,000 Accumulated depreciation—Professional library ....... (15,000) 18,000 Equipment ....................................................................... 75,800 Accumulated depreciation—Equipment ...................... (25,000) 50,800 Total assets ..................................................................... $115,864LiabilitiesAccounts payable ........................................................... $ 39,500 Salaries payable . (480)Unearned training fees .................................................. 7,500 Total liabilities ................................................................ 47,480EquityT. Wells, Capital .............................................................. 68,384 Total liabilities and equity ............................................. $115,864Problem 3-4A (45 minutes) —Part 1Cash ......................................... $ 86,000 $ 86,000 Accounts receivable ........... 15,000 (a) 4,000 19,000Office supplies ...................... 17,800 (b) 8,800 9,000Prepaid insurance ................ 6,040 (c) 2,080 3,960Office equipment .................. 87,000 87,000 Accumulated depreciation—Office equipment ........... $ 24,000 (d) 2,000 $ 26,000 Accounts payable ................ 9,100 (e) 14,900 24,000 Interest payable ..................... (f) 2,500 2,500 Salaries payable ................... (g) 15,000 15,000 Unearned consulting fees .20,000 (h) 7,000 13,000 Long-term notes payable .. 54,000 54,000 K. Jenkins, Capital ............... 46,000 46,000 K. Jenkins, Withdrawals .... 10,000 10,000Consulting feesearned .................................... 165,000 (a)(h)4,0007,000 176,000Depreciation expense—Office equipment ................ (d) 2,000 2,000Salaries expense .................. 67,990 (g) 15,000 82,990Interest expense ................... 1,270 (f) 2,500 3,770 Insurance expense .............. (c) 2,080 2,080Rent expense ........................ 14,540 14,540Office supplies expense .... (b) 8,800 8,800 Advertising expense ........... 12,460 _______ (e) 14,900 ______ 27,360 _______ Totals ........................................ $318,100 $318,100 $56,280 $56,280 $356,500 $356,500 Adjustment description(a) Earned but uncollected revenues.(b) Cost of office supplies used.(c) Cost of expired insurance coverage.(d) Depreciation expense on office equipment.(e) Incurred but unpaid advertising expense.(f) Incurred but unpaid interest expense.(g) Incurred but unpaid salaries expense.(h) Earned revenues previously received in advance.。
文体学 Chapter 03
Tense That will be John. That was John. It is raining and I have nothing to do, so I suppose I might as well write.
It was raining and he or she had nothing to do.
• (rules for the) arrangement of words into phrases and phrases into sentences • Syntax refers to the rules for ordering and connecting words into sentences. What is the right way of arranging the elements in a sentence.
III. Sentence Types simple sentence
compound
multiple sentence complex
complex compound
Major : conforming to the regular patterns
SPOCA • consisting of a dependent clause • non-finite construction • phrase • elliptical sentence • abbreviated sentence • block language
(how) (what)
situation type dynamic
sub-type action
verb type agentive
participant roles
广告学概论教案chapter03
第三章广告学与其他相关学科本章要点及学习要求本章主要阐述了广告学与其他相关学科如市场营销学、心理学和社会学的关系，以及相关学科理论在广告学中的应用。
从而认识到学习广告学这门综合性边缘学科不可缺少一些相关背景学科的理论基础。
广告学是一门综合性边缘交叉学科。
广告学的形成与发展受到各种相关学科的影响，在其形成过程中大量吸收各种相关学科的知识。
正是由于社会学、经济学、美学、统计学、市场学、管理学、心理学、传播学、新闻学、公共关系学等相关学科的发展，给广告学不断注入新的血液，才促使现代广告学在独立的学科轨道上不断丰富和发展。
广告学与这些学科相互影响，互相渗透，互相联系和包容，彼此之间建立了密切的关系。
因此有必要探讨广告学与其他学科之间的关系。
这里，我们主要讨论广告学与市场营销学、心理学和社会学等学科之间的关系。
因为这三者在广告实际应用中很有意义。
而后两者在广告学中的应用对广告学向纵深发展大有裨益。
第一节广告学与市场营销学一、广告学与市场营销学的关系广告活动和市场营销都是商品经济发展到了一定程度的产物。
作为一门学科，广告学的建立，也是市场经济孕育的结果。
市场营销学是在十九世纪末、二十世纪初，资本主义经济迅速发展时期创建的，广告学亦在这一时期兴起。
从一开始，这两门学科就紧密地结合在一起，相互影响，密不可分。
研究广告学，需要从市场营销的角度去审视、深入；研究市场营销学，又必须考虑广告的原理和运用。
从研究内容上看，它们同属于经济范畴。
市场营销是个人和群体通过创造并同他人交换产品和价值，以满足需求和欲望的一种社会和管理过程。
涉及需要、欲望和需求，产品、效用、交换、交易和关系，市场、市场营销和市场营销者等核心概念。
①而这些概念对于广告活动的理论和实务也是至关重要的。
广告是一种信息传播活动，但它的起点和落点都是在经济领域，传递什么样的信息内容以及如何进行传播，需要研究市场，了解营销环境，研究消费者，从满足消费者的需要和欲望出发；也需要研究产品，应适应不同的市场环境，制定相应的广告策略，争取较好的传播效果。
LNG液化天然气 Chapter 03 气液相平衡
3.1 Phase Behavior of Natural Gas
(2)纯组分p-T相图 C点：Critical Point 表示纯物质汽-液两相可 以共存的最高温度TC和最高 压力PC。 高于TC和PC，由虚线隔开 的区域为密流区。 密流区的流体称超临界流体，在这个区域流体的属性 不同与气体也不同于液体，它具有特殊的属性。
College of Chemistry & Chemical Engineering,SWPU
汽 C B 液 两相区
C临界点 T>TC D T=TC T<TC V
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Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
(2)多组分体系p-T相图 ①纯组分泡点线和露 点线重合为单一蒸气压曲 线，而多组分则存在露点
3、天然气的反凝析现象
pm 3 C 液 气液两相区 A B 温度T
College of Chemistry & Chemical Engineering,SWPU 17
1
气 4
(1)等温反凝析 (2)等温反蒸发
(3)等压反凝析
2
Tm
(4)等压反蒸发 将上述四种反常现 象统称作“反凝析现 象”。
Southwest Petroleum University
3.1 Phase Behavior of Natural Gas
天然气等温反凝析过程分析如下：
设体系原始态为A，等温降压A→F A→B(露点)降压 相变：气相→开始出现液相； B→D 降压： 相变：B→B1→B2→B3→D(反常相变) 液相：0→10→20→30→40％。 CDCTBC为反凝析区 D →E (露点) 降压： 相变：D→D3→D2→D1→E(正常相变) 液相：40→30→20→10→0％。 E→F降压：单一气相
北师大版七年级数学上册chapter-03§3.6《探索规律：算式规律》
习七年级数学上册§3.6《探索：算式规律》同步讲练【知识要点】1、探索规律就是一种观察、归纳、猜想、验证的过程.是一个创新意识的培养过程， 体现了从特殊到一般的数学思想2、探索规律主要是以下题型：（1）棋牌规律 （2）图形规律（重点） （3）剪纸规律 （4）算式规律（重点）【典例精析】一、算式规律例1．已知331＝，932＝，2733＝，8134＝，24335＝，72936＝，218737＝，……。
推测203的个位数字是______例2．观察下列顺序排列的等式：9×0＋1＝1， 9×1＋2＝11， 9×2＋3＝21， 9×3＋4＝31， 9×4＋5＝41，…… ．猜想：第n 个等式（n 为正整数）应为例3．观察下列各式，你会发现什么规律？ 3×5＝42－1 5×7＝62－1 7×9=112－1 ………请将你发现的规律用只含一个字母的表达式表示出来： 。
例4．已知：3223222⨯=+，8338332⨯=+，154415442⨯=+，…若ba ba ⨯=+21010（a 、b 为正整数），则a ＋b ＝ 。
例5．观察下列各式：3211=332123+=33221236++=33332123410+++=……猜想：3333123n ++++= ．例6．观察下列等式：223941401⨯=-， 224852502⨯=-，225664604⨯=-， 226575705⨯=-，228397907⨯=-…请你把发现的规律用字母表示出来： ．【基础巩固】1． 观察下列算式：122=，224=，328=，4216=，5232=，6264=，72128=，通过观察，用你所发现的规律确定272的个位数字是 （ ）A. 2B. 4C.6D. 8 2．观察下面的几个算式： 1+2+1=4 1+2+3+2+1=9 1+2+3+4+3+2+1=16 1+2+3+4+5+4+3+2+1=25根据上面几道题的规律，计算下面的题（1）1+2+3+…+9+…+3+2+1= 。
Chapter03第三章 空间平滑和空间插值
35第三章空间平滑和空间插值本章介绍基于GIS的空间分析中两个常用操作：空间平滑和空间插值。
空间平滑和空间插值关系密切，它们都可以用于显示空间分布态式及空间分布趋势，二者还共享某些算法（如核密度估计法Find/Replace All）。
空间平滑和空间插值的方法有很多种，本章只介绍其中最常用的几种。
空间平滑与移动平均在概念上类似（移动平均是求一个时间段内的均值），而空间平滑术是一个空间窗口内计算平均值。
第 3.1节介绍空间平滑的概念和方法，第 3.2节是案例分析3A，用空间平滑法研究中国南方/泰语地名(Find/Replace all)分布。
空间插值是用某些点的已知数值来估算其他点的未知数值。
第3.3节介绍了基于点的空间插值，第3.4节为案例3B，演示了一些常用的点插值法。
案例3B所用数据与3A相同，是案例3A工作的延伸。
第3.5节介绍基于面的空间插值，用一套面域数值（一般面单元较小）来估算另一个面域的数值（范围较大）。
面插值可用于数据融合以及不同面域单元的数据整合。
第 3.6节为案例3C，介绍两种简单的面插值法。
第3.7节为小结。
3.1空间平滑与移动平均法计算一个时间段的平均值（例如：五日平均温度）相似，空间平滑是将某点周围地区（定义为一个空间窗口）的平均值作为该点的平滑值，以此减少空间变异。
空间平滑适用面很广。
其中一种应用是处理小样本问题，我们在第八章会详细讨论。
对于那些人口较少的地区，由于小样本事件中随机误差的影响，癌症或谋杀等稀有事件发生率的估算不够可靠。
对于某些地区，这样的事情发生一次就可导致一个高发生率，而对于另外许多地区，没有发生这种事情的结果是零发生率。
另外一种应用是将离散的点数据转化为连续的密度图，从而考察点数据的空间分布模式，可参见下面的第3.2节。
本节介绍两种空间平滑方法（移动搜索法及核密度估计法），附录3介绍经验贝叶斯估计。
3.1.1移动搜索法移动搜索法（FCA）是以某点为中心画一个圆或正方形作为滤波窗口，用窗口内的平均值（或数值密度）作为该点的值。
北师大版七年级数学上册chapter-03§3.3《整式》
鼎吉教育（Dinj Education ）中小学生课外个性化辅导中心资料 北师大版七年级数学下册同步练习地址：佛山市南海区桂城南海大道丽雅苑中区会所2楼（南海体育馆对面） 1 鼎吉教育吉红勇老师编辑七年级数学下册§1.1《整式》同步讲练【知识要点】1、单项式的定义：2、在一个单项式中，所有字母 ，叫做这个单项式的 次数3、几个单项式的，叫做.4、和统称整式.5、注意：1) 单独一个字母或者数也是单项式 2) 非零常数是零次单项式【典例精析】例1．把下列代数式，分别填在相应的集合中：-5a 2,-ab,-3xy ,a 2-2ab,23n m -,1-22x ,13+m ，x 2，πy x -;单项式集合：{ …} 多项式集合：{…}整 式集合：{…}例2．在多项式-x 4＋2x 2y 2-y 4＋3xy 2-3x 2y 中填括号，要求把三次项相结合放在前面带有正号的括号里．例3．把多项式5x 3y-y 4-3xy 3+2x 2y 2-7.A.按y 的升幂排列；B.按x 的降幂排列.例4．指出下列多项式的项和系数： 1、多项式-2a 3+21b 3-61ab+a-2b 有 项，分别是： ，最高次项的系数是，这个多项式是次项式.例5、如图，求阴影部分的面积．【基础巩固】一．填空题：1、单项式-2πxy 2的系数是，次数是 . 2、多项式：5x 3-3x 2+2x+8是次项式.3、一辆汽车以x 千米/小时行驶d 千米路程，若速度加快10千米/小时，则可少用 小时 4、把多项式-5x 2-6x 4+2x-31x 3+5按字母x 的升幂排列为：5、下列代数式中，是单项式的有.①-15； ②32a ； ③π1x 2y; ④ a bc 32; ⑤3a+2b; ⑥0; ⑦ 7m6、单项式22ab 2c 的系数是 ，次数是 .7、πR 2是次单项式，-32是次单项式.8、某次旅游分甲、乙两组，已知甲组有a 名队员，平均门票m元，乙组有b 名队员，平均门票n 元，则一共要付门票___元． 9、某公司职员，月工资a 元，增加10%后达到________元． 10、如果一个两位数，十位上数字为x ，个位上数字为y ，则这个两位数为________．11、________和________统称整式． 12、单项式21xy 2z 是________次单项式．13、多项式a 2-21ab 2-b 2有_____项，其中-21ab 2的次数是____ 14、整式21，3x-y 2，23x 2y ，a ，πx ＋21y ，522a π，x ＋1中________是单项式，________是多项式． 15、x ＋2xy ＋y 是________次 项式．16、含盐20%的盐水x 千克，其中含盐_______千克，含水________千克．17、甲车的速度为每小时x 千米，乙车的速度为每小时y 千米．若甲、乙两车由两地同时出发，相向而行，t 小时后相遇，则两地距离为________千米．若两车同时分别从两地出发，同向而行，t 小时甲车追上乙车，则两地距离为________千米． 18、有一棵树苗，刚栽下去时，树高2.1米，以后每年长0.3米，则n 年后树高________米．二．判断题（对的画“√”，错的画“×”） （1）263m -是整式；（ ）（2）单项式6ab 3的系数是6，次数是4；（ ）鼎吉教育 遵循：“授人以鱼，不如授人以渔”的教育理念 . 秉承：以人为本，质量第一，突出特色， 服务家长 ◆ 以鲜明的教育理念启发人 ◆ 以浓厚的学习氛围影响人 第2页 以不倦的育人精神感染人 ◆ 以优良的学风学纪严律人◆（3）ac b 23-是多项式；（ ）（4）多项式5a-4322b a -的项是5a ，－42a 和-433b 各项的系数分别是5，－41，43；（ ）（5）如是a,b 都是自然数，那么x a+y b-3a+b是a+b 次三项式.（ ） 三．选择题1．制造一种产品，原来每件成本a 元，先提价5%，后降价5%，则此时该产品的成本价为( ) A ．不变 B ．a(1＋5%)2C ．a(1＋5%)(1-5%)D ．a(1-5%)22．某省为了解决药品价格过高的问题，决定大幅度降低药品价格，其中将原价为a 元的某种常用药降低40%，则降价后此药价格是( ) A ．4.0a 元 B ．6.0a 元 C ．60%a 元D ．40%a 元3．下列单项式次数为3的是( ) A ．3abcB ．2×3×4C ．41x 3yD ．52x4．下列代数式中整式有( )x1，2x+y ，31a 2b ，πyx -，xy 45，0.5，aA ．4个B ．5个C ．6个D ．7个5．下列整式中，单项式是( ) A ．3a ＋1B ．2x-yC ．0.1D ．21+x6、单项式-xy 2z 3的系数和次数分别是（ ）.A ．-1，5B ．0，6C ．-1，6D ．0，57、多项式-x 2-21x-1的各项分别是（ ）A ．-x 2, 21x,1;B ．-x 2,- 21x,-1;C ．x 2,21x,1; D ．以上答案都不对.8、下列说法正确的是（ ）.A ．21不是单项式； B ．ab 是单项式；C ．x 的系数是0；D ．223y x -是整式.9．（1）把多项式x 3-y 3-5x 2y+3xy 2按字母x 升幂排列；（2）把多项式4x 3y 2-xy 3-2x 2y 4+3x 4-5按x 的降幂排列，再按y的升幂排列.【能力提高】1、如果一个多项式是五次多项式，那么（ ） A ．这个多项式最多有六项；B ．这个多项式只能有一项的次数是六；C ．这个多项式一定是五次六项式；D ．这个多项式最少有二项，并且最高次项的次数是五. 2．第二十届电视剧飞天奖今年有a 部作品参赛，比去年增加了40%还多2部，设去年参赛作品有b 部，则b 等于( ) A ．%4012+-a B ．%4012++a C ．a(1+40%)+2 D ．a(1-40%)-23．随着计算机技术的迅猛发展，电脑价格不断降低，某品牌电脑按原售价降低m 元后，又降低20%，现售价为n 元，那么该电脑的原售价为( )A ．(54n ＋m)元B ．(45n ＋m)元C ．(5m ＋n)元D ．(5n ＋m)元4．小芳家去年结余6000元，估计今年可结余10000元，并且今年收入比去年高15%，支出比去年低10%．(1)若去年支出x 元，求去年收入多少元？今年的收入和支出各多少？(2)若今年支出x 元，则今年收入多少元，去年的收入和支出各多少？5．关于x 的多项式（a-4）x 3-x b+x-b 为二次三项式，求当x=-2这个二次三项式的值.6．一批运动服按原价85%（八五折）出售，每套售价为y 元，则这批运动服装原价为多少？7．请你写出一个四次项系数为-1的四次多项式，并指出其余各项的次数和系数．。
复变函数Chapter-03
dz = dx + idy
= ∫ xdx − ydy + i ∫ ydx + xdy
M N M N
∫ F ⋅ dr = ∫ Mdx + Ndy
c c β r r = ∫ F ( x (t ), y (t )) ⋅ r dt α
r
r
∫
C
f ( z )dz = ∫ (u + iv )(dx + idy )
(1)C : α = i → β = −i 的直线段； (2)C：左半平面以原点为中心 逆时针方向的单位半圆周。 解:(1) 线段αβ 的参数方程为 z = it ( t :1 → −1) dz = idt , z = it = t ⇒
−1
∫ f ( z )dz = 0
c
证：(不严格证明)假定 f ' ( z ) 连续，由Green公式得
C
C2 : z = eiθ , θ : 0 → π ⇒ 1 = i ∫ e dθ = e3θ i 3 0
3θ i π π
∫
C2
z 2 dz = ∫ e2θ i ieiθ dθ
0
π
∫ f ( z ) dz = ∫ f ( z ) dz + ∫
C C1
f ( z ) dz , C = C1 + C2
0
2 =− . 3
C C
特例：若f(z) = 1
= ∫ [u ( x(t ), y (t )) x ' (t ) − v( x(t ), y (t )) y ' (t )]dt
a
b
∫ dz = lim ∑ ∆z
c λ →0 k =1
n
k
Chapter 03_SA&GP
3.1 How to Convert an LP to Standard Form
Before the simplex algorithm can be used to solve an LP, the LP must be converted into a problem where all the constraints are equality equations and all variables are nonnegative. An LP in this form is said to be in standard form.
15
3.4 Why Does LP Have an Optimal bfs?
Theorem 3 If an LP has an optimal solution, then it has an optimal bfs. Proof: Omitted.
For any LP with m constraints, two basic feasible solutions are said to be adjacent if their sets of basic variables have m – 1 basic variables in common.
7
3.2 Preview of the Simplex Algorithm
Consider a system Ax = b of m linear independent equations in n variables (where n ≥ m). A basic solution to Ax = b is obtained by setting n–m variables equal to 0 (But setting which variables?) & solving for the remaining m variables. By setting the n–m variables equal to 0, which yields a unique value for the remaining m variables.
英国部分Chapter 03
Feudal System
This system of duties and rewards was called the Feudal System. In Normandy when barons or bishops were given land they had to swear an oath of loyalty to the lord who was giving it. This was called doing
1. The Hundred Year’s War 2. Joan of Arc
IV. The Black Death (1348-1349) and the Peasant Uprising (1381)
1. The Black Death 2. harm of the Black Death to the English society 3. The Lollards 4. Wat Tyler’s Uprising
英国社会与文化
2
I. Norman Rule (1066-1381)
1. William’s Rule (1066-1087) (1) The beginning of feudalism in England (2) feudalism in England under William the Conqueror
英国社会与文化 10
I. Norman Rule (1066-1381)
(4) quarrel between Henry II and Thomas Becket
Thomas Becket was Henry‟s intimate friend. Henry made Thomas Archbishop of Canterbury, hoping that he would assist him in carrying out legal reforms. A. Henry planned to reform the old Church Courts, to increase the jurisdiction of the civil courts at the expense of the church courts, to deprive the privileges enjoyed by the clergy
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3.2
集成运放
集成运放是高增益直接耦合多级放大器，组成框图如图 3-1 所示。输入级主要由差分放大 器构成，要求输入电阻高，零漂小。中间级主要提供电压放大倍数，通常由一级或两级有源负 载放大器构成。输出级一般由互补对称电路或准互补对称电路构成，有一定的输出功率，带负 载能力强。偏置电路的作用是为各级放大器设置稳定的工作点。 此外，集成运放还有一些辅助电路。例如，通过电平移动电路，实现“零输入时零输出” ； 双端输入转换成单端输出电路等。
3.2 集成运放
75
u I1 = u ID1 + u IC = u I 2 = u ID2 + u IC
1 ⎫ u ID + u IC ⎪ ⎪ 2 ⎬ 1 = − u ID +u IC ⎪ ⎪ 2 ⎭
（3-5
通过上式可以求得差放差模输入电压和共模输入电压分别为 uID=uI1−uI2
1 uIC= 2 (uI1+uI2)
β
IC2=
I REF ≈I 2 REF 1+
(β
2，2/β
1)
β
式中， IC2 为电流源恒定电流； IREF 称为参考电流或基准电流， 有 IREF=
U CC − U BE U CC ≈ R R
(UCC UBE)
可见，当 UCC、R 确定后，IREF 确定，IC2 随之确定，IC2 如同 IREF 的 镜像，故称镜像电流源。 例 3-1 分析图 3-5（a）所示电路。与图 2-20 所示基本共射放 大器比较，该电路有何特点。
（5）共模输入动态分析 在共模信号作用下，iE1、iE2 变化相同，即交流量 ie1=ie2，ie=2ie1，ue=ieRE=2ie1RE。对每管来 说，可认为 ie1 或 ie2 在流过 2RE 时产生 ue，由此可画共模交流通路如图 3-9（a）所示。
（3 （
（3-16
图 3-9
共模交流通路
a．双端输出 由于电路对称，总有 uc1=uc2，所以 RL 中无电流流过，可视为开路，交流通路如图 3-9（b） 所示。显然，uoC=0V，因此 u Ac= oC =0 uiC
式中，Au1 为单管共射放大器电压增益；RL′=RC//(RL/2)。 差模输入电阻 R iD 是从两个输入端看进去的等效电阻。容易看出 RiD=2(RB+rbe)
（3
76
第 3 章 集成运放及其应用
差模输出电阻 R oD 为
RoD=2RC b．单端输出 单端输出时，RL 接在 V1 集电极与地之间，交流通路如图 3-8（c）所示，所以 βRL' u u 1 Ad1= oD1 = oDl = Au1=− uiD 2uiDl 2 2(RB + rbe )
（3-
由于实际电路不可能完全对称，双端输出时 Ac 将是一很小数值，故 KCMR 很大。 b．单端输出 单端输出共模交流通路如图 3-9（c）所示，可以求得
3.1
概述
集成电路（Integration Circuit，简称 IC）是指将晶体管、电阻、电容及连接导线等集中制 作在一块很小的硅片上并加以封装，构成的具有一定功能的电路。
3.1.1
集成电路分类
根据导电类型，IC 分为双极型集成电路和单极型（即 MOS）集成电路（单极型指在 MOS 管中只有多子参与导电，或是自由电子或是空穴，而在双极型三极管中，自由电子和空穴都参 与导电） ；根据功能，IC 分为模拟集成电路和数字集成电路；根据集成度（单个芯片包含元器 件的数量） ， IC 分为小、 中、 大、 超大规模集成电路。 小规模集成电路 SSI （Small Scale Integration） 包含 10～100 个元器件，如集成运放、集成功放、集成稳压器和集成门电路等；中规模集成电 路 MSI（Medium Scale Integration）包含 100～1 000 个元器件，如四通用集成运放、集成触发 器、集成计数器、集成寄存器和集成译码器等；大规模集成电路 LSI（Large Scale Integration） 包含 1 000～100 000 个元器件， 如存储器和某些设备的控制器等； 超大规模集成电路 VLSI （Very Large Scale Integration）包含 100 000 个以上元器件，如大容量存储器等。
图 3-2
恒流源伏安特性
72
第 3 章 集成运放及其应用
却较小。 三极管工作在放大区，如果 IB 固定，IC 将呈现恒流特性，如图 3-3（a）所示。因此，利 用三极管可以组成电流源电路如图 3-3（b）所示，图中 IC 为电流源恒定电流。
图 3-3
三极管电流源
三极管电流源除图 3-3 所示基本形式外，还有其他多种形式。图 3-4 所示为镜像电流源， 其中 V1 与 V2 参数完全相同，即β1=β2=β，UBE1=UBE2=UBE，IB1=IB2=IB，IC1=IC2=IC。所以 2 IREF=IC1+2IB=IC2+2IB=IC2+ IC2
3.2 集成运放
71
3.1.2
集成电路的元器件
集成电路中的电阻有扩散电阻和金属膜电阻。电容利用 PN 结反偏电容或 MOS 管电容。 由于受制造工艺的限制，电阻和电容的数值不能很大，电阻值一般为几十欧至几千欧，电容量 在 200 pF 以下。对于电感，只能限于极小数值（微亨以下） 。因此，由集成电路组成电子线路 时，大电阻、大电容均需外接。此外，二极管一般是将 NPN 型三极管的 b、c 极短接而成。三 极管还有多发射极管和多集电极管。 思考与练习
图 3-6
典型差分放大器
（1）静态分析 典型差放直流通路如图 3-6（b）所示。由于两管电路参数相同，所以 IE1=IE2，IE=2IE1。由 图可得 IB1RB+UBE+2IE1RE=UEE 设两管电流放大系数均为β，又满足 UEE UBE，2RE RB/(1+β)，变换并化简上式得
74
第 3 章 集成运放及其应用
第3章
集成运放及其应用
学习目标
（1）了解集成运放的电路结构，理解单元电路（差分放大器、恒流源）的基本工作原理。 熟悉其符号、外形及引脚顺序。 （2）掌握放大电路中是否存在反馈、反馈的极性及负反馈类型的判断方法。 （3）理解反馈放大器的组成框图、负反馈对放大器性能的影响。 （4）掌握集成运放线性应用和非线性应用的方法，会分析典型的集成运放电路。 （5）会应用电阻测量法和电压测量法判断集成运放的质量，初步具备排除集成运放电路常 见故障的能力。 集成运算放大器简称集成运放，是发展最早、应用最广的模拟集成电路。集成运放最初用 于模拟计算机中实现数值运算，故有运算放大器之称。现在其应用已远远超出了模拟运算的范 围，但人们仍沿用运算放大器这一名称。本章首先简介集成运放的组成，然后重点讨论集成运 放的应用。由于集成运放在线性应用时广泛采用负反馈，所以本章还将讨论负反馈对电路性能 的影响。
式中，RL′=RC//RL。 差模输入电阻和输出电阻分别为
（
（3-13）
RiD=2(RB+rbe) RoD=RC 式（3-13）表明，在图 3-8 所示电压极性条件下，从 V1 集电极输出为反相输出。如果从 V2 集电极输出则为同相输出，并且有 u βRL' Ad2= oD2 =−Ad1= 2(RB + rbe ) uiD
当差放输入信号 uI 加在两输入端之间时，如图 3-7（a）所示，由于两管电路对称，所以 uI1=−uI2=uI/2，即为差模输入。
（
图 3-7
差模输入与共模输入
一对大小相等、极性相同的信号称为共模信号，均用 uIC 表示。差放两输入端加共模信号 时，称为共模输入。此时有 uI1=uI2=uIC。整个电路的共模输入信号就是共模输入电压，即 uI=uIC， 如图 3-7（b）所示。在共模输入电压 uIC 作用下，差放输出电压为共模输出电压 uOC。uOC 与 uIC 之比称为共模电压增益 Ac，即 u Ac= OC u IC 实际中，输入信号 uI1、uI2 是任意的。这时可将 uI1、uI2 的作用分解为一对差模信号和一对 共模信号的作用。设
可见，差放对共模信号具有抑制作用。为了全面衡量差分放大器放大差模信号，抑制共模信号 的能力，引入共模抑制比 KCMR，定义
（3
KCMR=
Ad Ac
（3
3.2 集成运放
77
（3-1
或
KCMR=20lg
Ad (dB) Ac
KCMR 越大，表明差分放大器放大差模信号，抑制共模信号的能力越强。 根据 KCMR 定义，可以求得双端输出时共模抑制比为 KCMR= Ad →∞ Ac
所以
（
uO=uOD+uOC=AduID+AcuIC 一般能满足⎪Ac⎪极小，甚至⎪Ac⎪→0，而⎪Ad⎪较大，⎪Ad⎪ ⎪Ac⎪，使 uOD uOC。所以 uO≈AduID=Ad(uI1−uI2) 上式表明，两输入端电压有差别，才有输出电压。差分放大器由此得名。 （3）差放的四种接法 差放有两个输入端和两个输出端，可根据实际需要，选择以下四种输入输出方式：双端输 入双端输出；单端输入双端输出；双端输入单端输出；单端输入单端输出。 （4）差模输入动态分析 在差模信号作用下，两管发射极电流 iE1、iE2 变化相反，因此流过 RE 的电流 iE=iE1+iE2 不变， RE 两端电压不变，所以 RE 对差模信号相当于短路，由图 3-7（a）可画出交流通路如图 3-8（a） 所示。
图 3-1
集成运放组成框图
关于集成运放的中间级与输出级在第 2 章已经介绍，本节讨论输入级和偏置电路。
3.2.1
集成运放的单元电路
1．电流源电路 电流源电路主要有两种用途：一是为各级放大器 提供稳定的工作点，即作偏置电路。二是作放大器的 负载，称为有源负载。 理想电流源就是恒流源，伏安特性如图 3-2 所示， 其两端电压 u 变化时，电流恒定不变，即ΔI=0，因 此， 交流电阻 r=Δu/Δi=ΔU/ΔI→∞， 直流电阻 R=U/I