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市场营销重点课程Ch04 消费者市场和购买行为分析

市场营销重点课程Ch04 消费者市场和购买行为分析

第四章第一部分消费者市场和购买行为分析(一)单项选择题(在下列每小题中,选择一个最合适的答案。

)1、_________是人类欲望行为最基本的决定因素。

A.文化B.性格C.国家D.社会2、消费者的购买单位是个人或_________。

A.集体B.家庭C.社会D.单位3、大多数消费者只能根据个人好恶和做出购买决策。

A.智慧B.经验C.感觉D.能力4、某种相关群体的有影响力的人物称为。

A.“意见领袖”B.“道德领袖”C.“精神领袖”D.“经济领导者”5、一个人的_________影响着消费需求和对市场营销因素的反应。

A.能力B.个性C.联系D.精神6、不同生活方式_________对产品和品牌有不同的需求。

A.群体B.社会C.模型D.艺术7、马斯洛认为需要按其重要程度分,最低层次需要是指_________。

A.生理需要B.社会需要C.尊敬需要D.安全需要8、_________在人格诸领域中最后形成,反映社会的各项准则,由理想、道德、良心等组成。

A.本我B.超我C.自我D.含我9、_________指存在于人体内驱使人们产生行为的内在刺激力,即内在需要。

A.刺激物B.诱因C.反应D.驱使力10、消费者购买过程是消费者购买动机转化为_________的过程。

A.购买心理B.购买意志C.购买行动D.购买意向11、体育明星和电影明星是其崇拜者的。

A.成员群体B.直接参照群体12、下列哪个因素不是影响消费者购买行为的主要因素_________。

A.文化因素B.社会因素C.自然因素D.个人因素13、对于减少失调感的购买行为,营销者要提供完善的_________,通过各种途径提供有利于本企业和产品的信息,使顾客确信自己购买决定的正确性。

A.售前服务B.售后服务C.售中服务D.无偿服务14、在复杂的购买行为中,消费者购买决策过程的第三个阶段是。

A.确认B.收集信息C.备选产品评估D.决定购买15、消费者对于有些产品品牌差异明显,但消费者不愿花长时间来选择和估价,而是不断变换所购产品的品牌,这种购买行为称为_________。

机器人机构学【ch04】串联机器人机构拓扑结构特征与综合 培训教学课件

机器人机构学【ch04】串联机器人机构拓扑结构特征与综合 培训教学课件
3)同一连杆上两运动副轴线平行,两者之间用“//”表示,如R//R,R//P,R//H, P//P等。
串联机器人机构拓扑结构特征
4)同一连杆上两运动副轴线相交于 一点,两者共用“⌒”表示。
5)若干个P副平行于同一平面,用 (-P-P-…-P-)表示。

6)同一连杆上两运动副轴线垂直,两者之间用“⊥”表示。
i(扭角):两相邻运动副轴线之间的夹角,即按右手坐标 系,绕xi轴线由zi到zi+1的转角。
串联机器人机构拓扑结构特征
1)两运动副轴线重合,即 αi=0,ai=0。
2)两运动副轴线平行,即 αi=0,ai≠0。
上述机器人连 杆的关节运动 副可特殊配置
如下:
3)两运动副轴线相交于一 点,即αi≠0,ai=0。

串联机器人机构拓扑结构特征
串联机器人机构的活动度公式
串联机器人机构的活动度公式为
m
F fi i1
式中,F为机构活动度;m为机构运动副数;fi为第i个运动副自由度数。
串联机器人机构拓扑结构特征
串联机器人机构运动输出特征矩阵
串联机器人机构的位移输出与速度输出
串联机器人机构的位移输出是末端连杆的位置与方向(位姿),为机构运动输入的函数。串
串联机器人机构运动输出特征方程
4)相互平行(重合)的两个转动必相关, 只对应一个独立转动输出。
5)平行于同一平面的三个转动必 相关。
“ 6)不平行于同一平面的四个转动必相关,三维空间内最多有三个独立的转动输出。 ”
03
串联机器人机构运动 输出特征矩阵运算
串联机器人机构运动输出特征矩阵运算 运动输出特征矩阵运算规则
步骤1 选定单开链的运动 输出特征矩阵MS。

Ch04 一阶过程和二阶过程的动态特性

Ch04 一阶过程和二阶过程的动态特性

峰值时间 最大超调nput Signals
Ramp function
xi
a
a=1 称为单位斜坡函数
0
1
t
Sinusoidal function
§4-1 Typical Input Signals
究竟采用哪种典型信号?
取决于系统在正常工况下最常见的输入信号形式 斜坡信号 阶跃信号 脉冲信号 正弦信号 随时间逐渐变化的输入 突然的扰动量、突变的输入 冲击输入 随时间往复变化的输入
1 0
5
wnt
10
15
阻尼系数、特征根与二阶系统单位阶跃响应
阻尼系数 特征根
[s]
二阶系统单位阶跃响应
[s]
[s]
阻尼系数、特征根与二阶系统单位阶跃响应
阻尼系数 特征根
[s]
二阶系统单位阶跃响应
[s]
[s]
§5-4 Time-domain Performance Specifications
时域分析性能指标是以系统对单位阶跃输入的瞬态响应 形式给出的。

§4-3 Transient Response of Second-order Systems
二阶系统:
能够用二阶微分方程描述的系统。 它的典型形式是二阶振荡环节。
形式一:
形式二:
二阶系统的单位阶跃响应
单位阶跃输入
则:
根据二阶系统的 极点分布特点, 分五种情况进行 讨论。
欠阻尼 临界阻尼 过阻尼 零阻尼 负阻尼
t
瞬态响应
稳态响应

——动态性能描述
——稳态性能描述
标准过程输入 一阶系统的瞬态响应 二阶系统的瞬态响应

离散数学CH04_图论_根树

离散数学CH04_图论_根树

4.6 树
4.6 树
图中的三棵树T1,T2和T3都是带权2,2,3,3,5
的二叉树,它们的权分别是:
W(T1)=2×2+2×2+3×3+5×3+3×2=38 W(T2)=3×4+5×4+3×3+2×2+2×1=47 W(T3)=3×3+3×3+5×2+2×2+2×2=36 以上三棵树都是带权2,2,3,3,5的赋权二叉树,但不 是最优树。
【例】求图所示的二叉树产 生的前缀码。 解:在图(a)中,每一个 分枝点引出的左侧边标记0, 右侧边标记1。由根结点到 树叶的路经上各边的标记组 成的0、1序列作为对应树叶 的标记,如图 (b)所示。产 生的前缀码为: 01,11,000,0010,0011
4.6 树
定理 任意一个前缀码,都对应一个二叉树。 证明:
4.6 树
给定了一个前缀码,设h是其中最长序列的长度。画出一个高为 h的正则二叉树。按定理9.6.7中描述的办法给各边标记0或1。 每一个结点对应一个0、1序列,它是由根结点到该结点的路经 上各边的标记组成的。如果某个0、1序列是前缀码的元素,则 标记该结点。将已标记结点的所有后代和该结点的射出边全部删 除,得到了一个二叉树,再删除未加标记的树叶,就得到要求的 二叉树。
在通信中常用0、1字符串表示英文字母,即用二进制 数表示英文字母。最少用多少位二进制数就能表示26
个英文字母呢?1位二进数可以表示2=21个英文字母
,两位二进制数可以表示4=22个英文字母,……,n 位二进制数可以表示2n个英文字母。如果规定,可以 用1位二进制数表示英文字母,也可以用两位二进制数 表示英文字母。
4.6 树
定理 在完全m叉树中,其树叶数为t,分枝点数为i,则 (m1)*i=t-1。 证明:

Ch04螺纹联接及螺纹传动-4

Ch04螺纹联接及螺纹传动-4

螺杆直径和长度、螺距、螺旋线头数、螺母高度。 5、螺纹公差的确定 6、螺旋副零件与滑板联接结构的确定
主要有刚性、弹性和活动联接结构。
三、滑动螺旋传动设计 1、滑动螺旋副的材料和结构
(1)滑动螺旋副的材料 (常用材料见表4-10) 1) 螺杆的材料应具有足够的强度和耐磨性,良好的可加工 性,对于精密传动螺旋,还要求在热处理后有较好的尺寸稳 定性。 2)螺母的材料除要求具有足够的强度外,还要求与螺杆配合 传动时摩擦因数小和耐磨性好,抗胶合能力强。 螺杆的材料:常用35、45号钢;需经热处理以达到高硬度的重 要螺杆,常用合金钢,如65Mn、40Cr、T12、20CrMnTi等。 螺母材料:常用材料有铸造青铜,如ZCuSn10Pb1, ZCuSn5Pb5Zn5;重载低速使用强度较高的铸造青铜ZCuAl10Fe3 或铸造黄铜ZCuZn25Al6Fe3Mn3 ;低速不重要的螺旋传动也可 用耐磨铸铁或灰铸铁。
螺 母
ZcuAl9Fe4Ni4 Mn2 ZCuZn25Al6Fe 3Mn3
注意:①要求强度耐磨性高,配对后f小,加工性好。 ②螺杆硬度高于螺母 (2)滑动螺旋副的结构
滑动螺旋副的结构主要是指螺杆、螺母的固定和支承的结构 形式。螺旋传动的工作刚度与精度等和支承结构有直接关系。
滑动螺旋传动采用梯形、矩形或锯齿形螺纹(多用梯形螺 纹,重载起重螺旋可用锯齿形螺纹, 对效率要求高时可用矩形 螺纹)。 螺母结构: 1)整体式——结构简单,但磨损后精度较差。 2)组合式——磨损后可补偿间隙、精度较高。 3)开合式——适合于双向传动,可提高传动精 度,消除空回误差。
螺距
F F FP p [ p] A d 2 h z d 2 h H
承载螺纹的圈数 一圈螺纹的承载面积

ch04统计分布的数值特征

ch04统计分布的数值特征

此称为加权算术平均公式。 可以证明,当f1= f2=…= fn时,
加权算术平均公式,将化为简 单算术平均公式。
表4-1 单变量分组表
组数i 1 2 3 …
标志变量xi x1 x2 x3 …
频数fi f1 f2 f3 …
n-1
xn-1
f n-1
n
xn
fn
-
合计
f
• Ch4 统计分布的数值特征

§4.1 数值平均数
6160
• Ch4 统计分布的数值特征

§4.1 数值平均数
§4.1.1 算术平均数
解:上表是50个工作日车流量的分布情况,只能作大概估计其日平均 车流量数。方法是计算其各组的组中值,用其组中值变量代替各组 的一般水平,然后进行加权求平均。即
n
x
(xi fi )
i 1 n
fi
6160 50
i 1
123.2(辆 /时).
f(x). 15
10
123.2
5
0
100 110 120 130 140 x
图4-3 某路口车流量分布
同时,我们也整理得到了该路口比较准确的车流量分布规律。
• Ch4 统计分布的数值特征

§4.1 数值平均数
§4.1.1 算术平均数
三、算术平均数的数学性质 ■各变量值与算术平均数的离差之和为零。
f1 f2 f3 ... fn
50
• Ch4 统计分布的数值特征

§4.1 数值平均数
§4.4.1 算术平均数
如果整理后的分布为组距变量分布,则必须用组中值变量 设数据组中值变量序列及相应的频数序列fi为
x i代替组距变量xi。

ch04 国际经济学课后答案与习题(萨尔瓦多)

*CHAPTER 4(Core Chapter)THE HECKSCHER-OHLIN AND OTHER TRADE THEORIESOUTLINE4.1 Introduction4.2 Factor Endowments and the Heckscher-Ohlin Theory4.3 The Formal Heckscher-Ohlin ModelCase Study 4-1 The Revealed Comparative Advantage of Various Countries and Regions4.4 Factor-Price Equalization and Income DistributionCase Study 4-2 Has International Trade Increased U.S. Wage Inequalities?4.5 Empirical Tests of the Heckscher-Ohlin Theory4.6 Economies of Scale and International TradeCase Study 4-3 The New International Economies of Scale4.7 Trade Based on Product DifferentiationCase Study 4-4 Growth of Intra-Industry Trade4.8 Technological Gap and Product Cycle ModelsCase Study 4-5: The United States as the Most Competitive Economy in the World4.9 Transportation Costs and International Trade4.10 Environmental Standards and International TradeAppendix The Specific-Factors Model and Intra-Industry Trade ModelsA4.1 The Specific-Factors ModelA4.2 A Model of Intra-Industry TradeKey TermsInternationalofscaleeconomies pricesRelativefactorproducts Heckscher–Ohlin (H–O) theory DifferentiatedtradeIntra-industryHeckscher–Ohlintheorem(H–O)Factor-proportions or factor-endowment theory Technological gap modelcyclemodelProductFactor–price equalization theoremcostsTransportationStolper-Samuelsontheoremmodel Nontraded goods and services Specific-factorsparadox Environmental standardsLeontiefMonopolisticcompetitionscalereturnsIncreasingtoLecture Guide1. This is one of the most important and difficult chapters in the book. It is also a long chapter andrequires four lectures to cover adequately.2. In the first lecture, I would cover sections 1-3. Section 3 is one of the most important sections inthe book because it presents the H-O model. I would proceed slowly and carefully in explaining Figure 4.1 and compare it to the standard trade model of Figure 3.4.3. In the second lecture, I would cover sections 4 and 5. Section 4 on the factor-price equalizationtheorem and income distribution is a difficult section. Case Study 4-2 should be of great interest to the students and give rise to a great deal of class discussion.4. In third lecture, I would cover sections sections 6-7, paying a great deal of attention to section 7on trade in differentiated products.5. In fourth lecture, I would cover the rest of the chapter.Answers to Review Questions and Problems1. a. The Heckscher–Ohlin (H-0) theorem postulates that a nation will export those commodi- ties whose production requires the intensive use of the nation’s relatively abundant and cheap factor and import the commodities whose production requires the intensive useof the nation’s relatively scarce and expensive factor. In short, the relatively labor-richnation exports relatively labor-intensive commodities and imports the relativelycapital-intensive commodities.b. Heckscher and Ohlin identify the relative difference in factor endowments amongnations as the basic determinant of comparative advantage and international trade.c. The H-O Theory represent an extension of the standard trade model because it explains the basis for comparative advantage (classical economists, such as Ricardo had assumed it) and examines the effect of international trade on factor prices and income distribution (which classical economists had left unanswered).2. See Figure 1 on the next page.3. a. The factor–price equalization theorem postulates that international trade will bring about the equalization of the returns to homogeneous or identical factors across nations.b. The Stopler-Samuelson theorem postulates that free international trade reduces the realincome of the nation’s relatively scarce factor and increases the real income of the nation’s relatively abundant factor.Fig 4.1Fig 4.2XXb. The specific-factors model postulates that the opening of trade (1) benefits the specific factorused in the production of the nation’s export commodity, (2) harms the specific factor used in the production of the nation’s import-competing industry, and (3) leads to an ambiguouseffect (i.e., it may benefit or harm) the mobile factor.c. Trade acts as a substitute for the international mobility of factors of production in itseffect on factor prices. With perfect mobility, labor would migrate from the low-wagenation to the high-wage nation until wages in the two nations are equalized. Similarly,capital would move from the low-interest to the high-interest nation until the rate ofinterest was equalized in the two nations.4. a. The Leontief paradox refers to the original Leontief’s finding that U.S. import substituteswere more K-intensive than U.S. exports. This was the opposite of what the H-O theorempostulated.b. The Leontief paradox was resolved by including human capital into the calculations andexcluding industries based on natural resources. Recent research using data on many sectors, for many countries, over many years, and considering that countries could specialize in aparticular subset or group of commodities that were best suited to their specific factorendowments, provides strong support for the H-O theorem.c. The Hecksher-Olhin theory remains the centerpiece of modern trade theory for explaininginternational trade today. To be sure, there are other forces (such as economies of scale,product differentiation, and technological differences across countries) that provide additional reasons and explanations for some international trade not explained by the basic H-O model.These other trade theories complement the basic H-O model in explaining the pattern ofinternational trade in the world today.5. International trade with developing economies, especially newly industrializing economies (NIEs), contributed in two ways to increased wage inequalities between skilled and unskilled workers in the United States during the past two decades. Directly, by reducing the demand for unskilledworkers as a result of increased U.S. imports of labor-intensive manufactures and, indirectly, byspeeding up the introduction of labor-saving innovations, which further reduced the U.S.demand for unskilled workers. International trade, however, was only a small cause of increased wage inequalities in the United States. The most important cause was technological change.6. a. Economies of scale refer to the production situation where output grows proportionatelymore than the increase in inputs or factors of production. For example, output may morethan double with a doubling of inputs.b. Even if two nations were identical in every respect, there is still a basis for mutually bene-ficial trade based on economies of scale. When each nation specializes in the production of one commodity, the combined total world output of both commodities will be greater thanthan without specialization when economies of scale are present. With trade, each nationthen shares in these gains.c. The new international economies of scale refers to the increase in productivity resultingfrom firms purchasing parts and components from nations where they are made cheaperand better, and by establishing production facilities abroad-26-7. a. Product differentiation refers to products that are similar, but not identical. Intra-industrytrade refers to trade in differentiated products, as opposed to inter-industry trade incompletely different products.b. Intra-industry trade arises in order to take advantage of important economies of scale inproduction. That is, with intra-industry trade each firm or plant in industrial countries canspecialize in the production of only one, or at most a few, varieties and styles of the sameproduct rather than many different varieties and styles of a product and achieve economies of scale.c. With few varieties and styles, more specialized and faster machinery can be developedfor a continuous operation and a longer production run. The nation then imports othervarieties and styles from other nations. Intra-industry trade benefits consumers because ofthe wider range of choices (i.e., the greater variety of differentiated products) available atthe lower prices made possible by economies of scale in production.8. a. According to the technological gap model, a firm exports a new product until imitators incountries take away its market. In the meantime, the innovating firm will have introduced a new product or process.b. The criticism of the technological gap model are that it does not explain the size of techno- logical gaps and does not explore the reason for technological gaps arising in the first place, or exactly how they are eliminated over time.c. The five stages of the product cycle model are: the introduction of the product, expansion of production for export, standardization and beginning of production abroad through imitation, foreign imitators underselling the nation in third markets, and foreigners underselling theinnovating firms in their home market as well.9. See Figure 2 on page 25.10. A nation with lower environmental standards can use the environment as a resource endow-ment or as a factor of production in attracting polluting firms from abroad and achieving acomparative advantage in the production of polluting goods and services. This can lead totrade disputes with nations with more stringent environmental standards.-27-Multiple-Choice Questions1. The H-O model extends the classical trade model by:a. explaining the basis for comparative advantageb. examining the effect of trade on factor prices*c. both a and bd. neither a nor b2. A nation is said to have a relative abundance of K if it has a:a. greater absolute amount of Kb. smaller absolute amount of Lc. higher L/K ratio*d. lower price of K in relation to the price of L3. A difference in relative commodity prices between nations can be based on a difference in:a. technologyb. factor endowmentsc. tastes*d. all of the above4. In the H-O model, international trade is based mostly on a difference in:a. technology*b. factor endowmentsc. economies of scaled. tastes5. According to the H-O theory, trade reduces international differences in:a. commodity pricesb. in factor prices*c. both commodity and factor pricesd. neither relative nor absolute factor prices6. According to the Stolper-Samuelson theorem, international trade leads toa. reduction in the real income of the nation’s relatively abundant factor*b. reduction in the real income of the nation’s relatively scarce factorc. increase in the real income of the nation’s relatively scarce factord. none of the above7. Which of the following is false with regard to the specific factors theorem, international trade *a. harms the immobile factors that are specific to the nation’s export commodities or sectorsb. harms the immobile factors that are specific to the nation’s import-competing commoditiesc. has an ambiguous effect on the nation’s mobile factorsd. may benefit or harm the nation’s mobile factors8. Perfect international mobility of factors of productiona. leads to a reduction in international differences in the returns to homogenous factorsb. acts as a substitute for international trade in its effects on factor pricesc. operates on the supply of factors in affecting factor prices*d. all of the above9. The Leontief paradox refers to the empirical finding that U.S.*a. import substitutes were more K-intensive than exportsb. exports were more L-intensive than importsc. exports were more K-intensive than import substitutesd. all of the above10. From empirical studies, we conclude that the H-O theory:a. must be rejectedb. must be accepted without reservations*c. can generally be acceptedd. explains all international trade11. International trade can be based on economies of scale even if both nations have identical:a. factor endowmentsb. tastesc. technology*d. all of the above12. A great deal of international trade:a. is intra-industry tradeb. involves differentiated productsc. is based on monopolistic competition*d. all of the above13. Intra-industry trade takes place:a. because products are homogeneous*b. in order to take advantage of economies of scalec. because perfect competition is the prevalent form of market organizationd. all of the above14. Which of the following statements is true with regard to the product-cycle theory?a. it depends on differences in technological changes over time among countriesb. it depends on the opening and the closing of technological gaps among countriesc. it postulates that industrial countries export more advanced products to lessadvanced countries*d. all of the above15. Transport costs:a. increase the price in the importing countryb. reduces the price in the exporting countryc. falls less heavily on the nation with the more elastic demand and supply curves of the traded commodity*d. all of the above-30-ADDITIONAL ESSAYS AND PROBLEMS FOR PART ONE1. Assume that both the United States and Germany produce beef and computer chips with the following costs:United States Germany(dollars) (marks)Unit cost of beef (B) 2 8Unit cost of computer chips (C) 1 2(a) What is the opportunity cost of beef (B) and computer chips (C) in each country?(b) In which commodity does the United States have a comparative cost advantage?What about Germany?(c) What is the range for mutually beneficial trade between the United States and Germanyfor each computer chip traded?(b) How much would the United States and Germany gain if 1 unit of beef is exchangedfor 3 chips?Answ. (a) In the United States:the opportunity cost of one unit of beef is 2 chips;the opportunity cost of one chip is 1/2 unit of beef.In Germany:the opportunity cost of one unit of beef is 4 chips;the opportunity cost of one chip is 1/4 unit of beef.(b) The United States has a comparative cost advantage in beef with respect to Germany,while Germany has a comparative cost advantage in computer chips.(c) The range for mutually beneficial trade between the United States and Germany foreach unit of beef that the United States exports is2C < 1B < 4C(d) Both the United States and Germany would gain 1 chip for each unit of beef traded.2. Given: (1) two nations (1 and 2) which have the same technology but different factor costs conditions, and (3) no transportation costs, tariffs, or other obstructions to trade.Prove geometrically that mutually advantageous trade between the two nations is possible.Note: Your answer should show the autarky (no-trade) and free-trade points of production and consumption for each nation, the gains from trade of each nation, and express the equilibrium condition that should prevail when trade stops expanding.)Ans.: See the figure below.Fig 4.3Fig 4.4Nations 1 and 2 have different production possibilities curves and different community indifference maps. With these, they will usually end up with different relative commodity prices in autarky, thus making mutually beneficial trade possible.In the figure, Nation 1 produces and consumes at point A and Px/Py=P A in autarky, while Nation 2 produces and consumes at point A' and Px/Py=P A'. Since P A < P A', Nation 1 has a comparative advantage in X and Nation 2 in Y. Specialization in production proceeds until point B in Nation 1 and point B' in Nation 2, at which P B =P B' and the quantity supplied for export of each commodity exactly equals the quantity demanded for import.Thus, Nation 1 starts at point A in production and consumption in autarky, moves to point B in production, and by exchanging BC of X for CE of Y reaches point E in consumption. E > A since it involves more of both X and Y and lies on a higher community indifference curve.Nation 2 starts at A' in production and consumption in autarky, moves to point B' in production, and by exchanging B'C' of Y for C'E' of X reaches point E'in consumption (which exceeds A').At Px/Py=P B =P B', Nation 1 wants to export BC of X for CE of Y, while Nation 2 wants to export B'C' (=CE) of Y for C'E' (=BC) of X. Thus, P B =P B' is the equilibrium relative commodity price because it clears both (the X and Y) markets.3. (a) Identify the conditions that may give rise to trade between two nations. (b) What aresome of the assumptions on which the Heckscher-Ohlin theory is based? (c) What does this theory say about the pattern of trade and effect of trade on factor prices?Ans. (a) Trade can be based on a difference in factor endowments, technology, or tastesbetween two nations. A difference either in factor endowments or technology results in a different production possibilities frontier for each nation, which, unlessneutralized by a difference in tastes, leads to a difference in relative commodity price and mutually beneficial trade. If two nations face increasing costs and have identical production possibilities frontiers but different tastes, there will also be a differencein relative commodity prices and the basis for mutually beneficial trade between the two nations. The difference in relative commodity prices is then translated into adifference in absolute commodity prices between the two nations, which is the immediate cause of trade.(b) The Heckscher-Ohlin theory (sometimes referred to as the modern theory – asopposed to the classical theory - of international trade) assumes that nations have the same tastes, use the same technology, face constant returns to scale (i.e., a givenpercentage increase in all inputs increases output by the same percentage) but differ widely in factor endowments. It also says that in the face of identical tastes or demand conditions, this difference in factor endowments will result in a difference in relative factor prices between nations, which in turn leads to a difference in relativecommodity prices and trade. Thus, in the Heckscher-Ohlin theory, the internationaldifference in supply conditions alone determines the pattern of trade. To be noted is that the two nations need not be identical in other respects in order for internationaltrade to be based primarily on the difference in their factor endowments.(c) The Heckscher-Ohlin theorem postulates that each nation will export the commodityintensive in its relatively abundant and cheap factor and import the commodityintensive in its relatively scarce and expensive factor. As an important corollary, itadds that under highly restrictive assumptions, trade will completely eliminate thepretrade relative and absolute differences in the price of homogeneous factors amongnations. Under less restrictive and more usual conditions, however, trade will reduce, but not eliminate, the pretrade differences in relative and absolute factor prices among nations. In any event, the Heckscher-Ohlin theory does say something very useful onhow trade affects factor prices and the distribution of income in each nation. Classical economists were practically silent on this point.-33-4. Suppose that tastes change in Nation 1 (the L-abundant and L-cheap nation) so that consumers demand more of commodity X (the L-intensive commodity) and less of commodity Y (the K- intensive commodity). Suppose that Nation 1 is India, commodity X is textiles, and commodi- ty Y is food. Starting from the no-trade equilibrium position and using the Heckscher-Ohlinmodel, trace the effect of this change in tastes on India's (a) relative commodity prices anddemand for food and textiles, (b) production of both commodities and factor prices, and(c) comparative advantage and volume of trade. (d) Do you expect international trade to leadto the complete equalization of relative commodity and factor prices between India and theUnited States? Why?Ans. (a) The change in tastes can be visualized by a shift toward the textile axis in India'sindifference map in such a way that an indifference curve is tangent to the steepersegment of India's production frontier (because of increasing opportunity costs) after the increase in demand for textiles. This will cause the pretrade relative commodity price of textiles to rise in India.(b) The increase in the relative price of textiles will lead domestic producers in India toshift labor and capital from the production of food to the production of textiles. Since textiles are L-intensive in relation to food, the demand for labor and therefore the wage rate will rise in India. At the same time, as the demand for food falls, thedemand for and thus the price of capital will fall. With labor becoming relative more expensive, producers in India will substitute capital for labor in the production of both textiles and food.(c) Even with the rise in relative wages and in the relative price of textiles, India stillremains the L-abundant and low-wage nation with respect to a nation such as theUnited States. However, the pretrade difference in the relative price of textilesbetween India and the United States is now somewhat smaller than before the change in tastes in India. As a result the volume of trade required to equalize relativecommodity prices and hence factor prices is smaller than before. That is, India need now export a smaller quantity of textiles and import less food than before for therelative price of textiles in India and the United States to be equalized. Similarly, the gap between real wages and between India and the United States is now smaller and can be more quickly and easily closed (i.e., with a smaller volume of trade).(d) Since many of the assumptions required for the complete equalization of relativecommodity and factor prices do not hold in the real world, great differences can be expected and do in fact remain between real wages in India and the United States.Nevertheless, trade would tend to reduce these differences, and the H-O model does identify the forces that must be considered to analyze the effect of trade on thedifferences in the relative and absolute commodity and factor prices between Indiaand the United States.-34-5. (a) Explain why the Heckscher-Ohlin trade model needs to be extended. (b) Indicate in what important ways the Heckscher-Ohlin trade model can be extended. (c) Explain what ismeant by differentiated products and intra-industry trade.Ans. (a) The Heckscher-Ohlin trade model needs to be extended because, while generallycorrect, it fails to explain a significant portion of international trade, particularly the trade in manufactured products among industrial nations.(b) The international trade left unexplained by the basic Heckscher-Ohlin trade model canbe explained by (1) economies of scale, (2) intra-industry trade, and (3) trade based on imitation gaps and product differentiation.(c) Differentiated products refer to similar, but not identical, products (such as cars,typewriters, cigarettes, soaps, and so on) produced by the same industry or broadproduct group. Intra-industry trade refers to the international trade in differentiated products.-35-。

ch04国际经济学课后答案与习题(萨尔瓦多)

ch04国际经济学课后答案与习题(萨尔⽡多)*CHAPTER 4(Core Chapter)THE HECKSCHER-OHLIN AND OTHER TRADE THEORIESOUTLINE4.1 Introduction4.2 Factor Endowments and the Heckscher-Ohlin Theory4.3 The Formal Heckscher-Ohlin ModelCase Study 4-1 The Revealed Comparative Advantage of Various Countries and Regions4.4 Factor-Price Equalization and Income DistributionCase Study 4-2 Has International Trade Increased U.S. Wage Inequalities?4.5 Empirical Tests of the Heckscher-Ohlin Theory4.6 Economies of Scale and International TradeCase Study 4-3 The New International Economies of Scale4.7 Trade Based on Product DifferentiationCase Study 4-4 Growth of Intra-Industry Trade4.8 Technological Gap and Product Cycle ModelsCase Study 4-5: The United States as the Most Competitive Economy in the World4.9 Transportation Costs and International Trade4.10 Environmental Standards and International TradeAppendix The Specific-Factors Model and Intra-Industry Trade ModelsA4.1 The Specific-Factors ModelA4.2 A Model of Intra-Industry TradeKey TermsInternationalofscaleeconomies pricesRelativefactorproducts Heckscher–Ohlin (H–O) theory DifferentiatedtradeIntra-industryHeckscher–Ohlintheorem(H–O)Factor-proportions or factor-endowment theory Technological gap modelcyclemodelProductFactor–price equalization theoremcostsTransportationStolper-Samuelsontheoremmodel Nontraded goods and services Specific-factorsparadox Environmental standardsLeontiefMonopolisticcompetitionscalereturnsIncreasingtoLecture Guide1. This is one of the most important and difficult chapters in the book. It is also a long chapter andrequires four lectures to cover adequately.2. In the first lecture, I would cover sections 1-3. Section 3 is one of the most important sections inthe book because it presents the H-O model. I would proceed slowly and carefully in explaining Figure 4.1 and compare it to the standard trade model of Figure 3.4.3. In the second lecture, I would cover sections 4 and 5. Section 4 on the factor-price equalizationtheorem and income distribution is a difficult section. Case Study 4-2 should be of great interest to the students and give rise to a great deal of class discussion.4. In third lecture, I would cover sections sections 6-7, paying a great deal of attention to section 7on trade in differentiated products.5. In fourth lecture, I would cover the rest of the chapter.Answers to Review Questions and Problems1. a. The Heckscher–Ohlin (H-0) theorem postulates that a nation will export those commodi- ties whose production requires the intensive use of the nation’s relatively abundant and cheap factor and import the commodities whose production requires the intensive useof the nation’s relatively scarce and expensive factor. In short, the relatively labor-richnation exports relatively labor-intensive commodities and imports the relativelycapital-intensive commodities.b. Heckscher and Ohlin identify the relative difference in factor endowments amongnations as the basic determinant of comparative advantage and international trade.c. The H-O Theory represent an extension of the standard trade model because it explains the basis for comparative advantage (classical economists, such as Ricardo had assumed it) and examines the effect of international trade on factor prices and income distribution (which classical economists had left unanswered).2. See Figure 1 on the next page.3. a. The factor–price equalization theorem postulates that international trade will bring about the equalization of the returns to homogeneous or identical factors across nations.b. The Stopler-Samuelson theorem postulates that free international trade reduces the realincome of the nation’s relatively scarce factor and increases the real income of the nation’s relatively abundant factor.Fig 4.1Fig 4.2XXb. The specific-factors model postulates that the opening of trade (1) benefits the specific factorused in the production of the nation’s export commodity, (2) harms the specific factor used in the production of the nation’s import-competing industry, and (3) leads to an ambiguouseffect (i.e., it may benefit or harm) the mobile factor.c. Trade acts as a substitute for the international mobility of factors of production in itseffect on factor prices. With perfect mobility, labor would migrate from the low-wagenation to the high-wage nation until wages in the two nations are equalized. Similarly,capital would move from the low-interest to the high-interest nation until the rate ofinterest was equalized in the two nations.4. a. The Leontief paradox refers to the original Leontief’s finding that U.S. import substituteswere more K-intensive than U.S. exports. This was the opposite of what the H-O theorempostulated.b. The Leontief paradox was resolved by including human capital into the calculations andexcluding industries based on natural resources. Recent research using data on many sectors, for many countries, over many years, and considering that countries could specialize in aparticular subset or group of commodities that were best suited to their specific factorendowments, provides strong support for the H-O theorem.c. The Hecksher-Olhin theory remains the centerpiece of modern trade theory for explaininginternational trade today. To be sure, there are other forces (such as economies of scale,product differentiation, and technological differences across countries) that provide additional reasons and explanations for some international trade not explained by the basic H-O model.These other trade theories complement the basic H-O model in explaining the pattern ofinternational trade in the world today.5. International trade with developing economies, especially newly industrializing economies (NIEs), contributed in two ways to increased wage inequalities between skilled and unskilled workers in the United States during the past two decades. Directly, by reducing the demand for unskilledworkers as a result of increased U.S. imports of labor-intensive manufactures and, indirectly, byspeeding up the introduction of labor-saving innovations, which further reduced the U.S.demand for unskilled workers. International trade, however, was only a small cause of increased wage inequalities in the United States. The most important cause was technological change.6. a. Economies of scale refer to the production situation where output grows proportionatelymore than the increase in inputs or factors of production. For example, output may morethan double with a doubling of inputs.b. Even if two nations were identical in every respect, there is still a basis for mutually bene-ficial trade based on economies of scale. When each nation specializes in the production of one commodity, the combined total world output of both commodities will be greater thanthan without specialization when economies of scale are present. With trade, each nationthen shares in these gains.c. The new international economies of scale refers to the increase in productivity resultingfrom firms purchasing parts and components from nations where they are made cheaperand better, and by establishing production facilities abroad-26-7. a. Product differentiation refers to products that are similar, but not identical. Intra-industrytrade refers to trade in differentiated products, as opposed to inter-industry trade incompletely different products.b. Intra-industry trade arises in order to take advantage of important economies of scale inproduction. That is, with intra-industry trade each firm or plant in industrial countries canspecialize in the production of only one, or at most a few, varieties and styles of the sameproduct rather than many different varieties and styles of a product and achieve economies of scale.c. With few varieties and styles, more specialized and faster machinery can be developedfor a continuous operation and a longer production run. The nation then imports othervarieties and styles from other nations. Intra-industry trade benefits consumers because ofthe wider range of choices (i.e., the greater variety of differentiated products) available atthe lower prices made possible by economies of scale in production.8. a. According to the technological gap model, a firm exports a new product until imitators incountries take away its market. In the meantime, the innovating firm will have introduced a new product or process. b. The criticism of the technological gap model are that it does not explain the size of techno- logical gaps and does not explore the reason for technological gaps arising in the first place, or exactly how they are eliminated over time.c. The five stages of the product cycle model are: the introduction of the product, expansion of production for export, standardization and beginning of production abroad through imitation, foreign imitators underselling the nation in third markets, and foreigners underselling theinnovating firms in their home market as well.9. See Figure 2 on page 25.10. A nation with lower environmental standards can use the environment as a resource endow-ment or as a factor of production in attracting polluting firms from abroad and achieving acomparative advantage in the production of polluting goods and services. This can lead totrade disputes with nations with more stringent environmental standards.-27-Multiple-Choice Questions1. The H-O model extends the classical trade model by:a. explaining the basis for comparative advantageb. examining the effect of trade on factor prices*c. both a and bd. neither a nor b2. A nation is said to have a relative abundance of K if it has a:a. greater absolute amount of Kb. smaller absolute amount of Lc. higher L/K ratio*d. lower price of K in relation to the price of L3. A difference in relative commodity prices between nations can be based on a difference in:a. technologyb. factor endowmentsc. tastes*d. all of the above4. In the H-O model, international trade is based mostly on a difference in:a. technology*b. factor endowmentsc. economies of scaled. tastes5. According to the H-O theory, trade reduces international differences in:a. commodity pricesb. in factor prices*c. both commodity and factor pricesd. neither relative nor absolute factor prices6. According to the Stolper-Samuelson theorem, international trade leads toa. reduction in the real income of the nation’s relatively abundant factor*b. reduction in the real income of the nation’s relatively scarce factorc. increase in the real income of the nation’s relatively scarce factord. none of the above7. Which of the following is false with regard to the specific factors theorem, international trade *a. harms the immobile factors that are specific to the nation’s export commodities or sectorsb. harms the immobile factors that are specific to the nation’s import-competing commoditiesc. has an ambiguous effect on the nation’s mobile factorsd. may benefit or harm the nation’s mobile factors8. Perfect international mobility of factors of productiona. leads to a reduction in international differences in the returns to homogenous factorsb. acts as a substitute for international trade in its effects on factor pricesc. operates on the supply of factors in affecting factor prices*d. all of the above9. The Leontief paradox refers to the empirical finding that U.S.*a. import substitutes were more K-intensive than exportsb. exports were more L-intensive than importsc. exports were more K-intensive than import substitutesd. all of the above10. From empirical studies, we conclude that the H-O theory:a. must be rejectedb. must be accepted without reservations*c. can generally be acceptedd. explains all international trade11. International trade can be based on economies of scale even if both nations have identical:a. factor endowmentsb. tastesc. technology*d. all of the above12. A great deal of international trade:a. is intra-industry tradeb. involves differentiated productsc. is based on monopolistic competition*d. all of the above13. Intra-industry trade takes place:a. because products are homogeneous*b. in order to take advantage of economies of scalec. because perfect competition is the prevalent form of market organizationd. all of the above14. Which of the following statements is true with regard to the product-cycle theory?a. it depends on differences in technological changes over time among countriesb. it depends on the opening and the closing of technological gaps among countriesc. it postulates that industrial countries export more advanced products to lessadvanced countries*d. all of the above15. Transport costs:a. increase the price in the importing countryb. reduces the price in the exporting countryc. falls less heavily on the nation with the more elastic demand and supply curves of the traded commodity*d. all of the above-30-ADDITIONAL ESSAYS AND PROBLEMS FOR PART ONE1. Assume that both the United States and Germany produce beef and computer chips with the following costs: United States Germany(dollars) (marks)Unit cost of beef (B) 2 8Unit cost of computer chips (C) 1 2(a) What is the opportunity cost of beef (B) and computer chips (C) in each country?(b) In which commodity does the United States have a comparative cost advantage?What about Germany?(c) What is the range for mutually beneficial trade between the United States and Germanyfor each computer chip traded?(b) How much would the United States and Germany gain if 1 unit of beef is exchangedfor 3 chips?Answ. (a) In the United States:the opportunity cost of one unit of beef is 2 chips;the opportunity cost of one chip is 1/2 unit of beef.In Germany:the opportunity cost of one unit of beef is 4 chips;the opportunity cost of one chip is 1/4 unit of beef.(b) The United States has a comparative cost advantage in beef with respect to Germany,while Germany has a comparative cost advantage in computer chips.(c) The range for mutually beneficial trade between the United States and Germany foreach unit of beef that the United States exports is2C < 1B < 4C(d) Both the United States and Germany would gain 1 chip for each unit of beef traded.2. Given: (1) two nations (1 and 2) which have the same technology but different factor costs conditions, and (3) no transportation costs, tariffs, or other obstructions to trade.Prove geometrically that mutually advantageous trade between the two nations is possible.Note: Your answer should show the autarky (no-trade) and free-trade points of production and consumption for each nation, the gains from trade of each nation, and express the equilibrium condition that should prevail when trade stops expanding.) Ans.: See the figure below.Fig 4.3Fig 4.4Nations 1 and 2 have different production possibilities curves and different community indifference maps. With these, they will usually end up with different relative commodity prices in autarky, thus making mutually beneficial trade possible.In the figure, Nation 1 produces and consumes at point A and Px/Py=P A in autarky, while Nation 2 produces and consumes at point A' and Px/Py=P A'. Since P A < P A', Nation 1 has a comparative advantage in X and Nation 2 in Y. Specialization in production proceeds until point B in Nation 1 and point B' in Nation 2, at which P B =P B' and the quantity supplied for export of each commodity exactly equals the quantity demanded for import.Thus, Nation 1 starts at point A in production and consumption in autarky, moves to point B in production, and by exchanging BC of X for CE of Y reaches point E in consumption. E > A since it involves more of both X and Y and lies on a higher community indifference curve.Nation 2 starts at A' in production and consumption in autarky, moves to point B' in production, and by exchanging B'C' of Y for C'E' of X reaches point E'in consumption (which exceeds A').At Px/Py=P B =P B', Nation 1 wants to export BC of X for CE of Y, while Nation 2 wants to export B'C' (=CE) of Y for C'E' (=BC) of X. Thus, P B =P B' is the equilibrium relative commodity price because it clears both (the X and Y) markets.3. (a) Identify the conditions that may give rise to trade between two nations. (b) What aresome of the assumptions on which the Heckscher-Ohlin theory is based? (c) What does this theory say about the pattern of trade and effect of trade on factor prices?Ans. (a) Trade can be based on a difference in factor endowments, technology, or tastesbetween two nations. A difference either in factor endowments or technology results in a different production possibilities frontier for each nation, which, unlessneutralized by a difference in tastes, leads to a difference in relative commodity price and mutually beneficial trade. If two nations face increasing costs and have identical production possibilities frontiers but different tastes, there will also be a differencein relative commodity prices and the basis for mutually beneficial trade between the two nations. The difference in relative commodity prices is then translated into adifference in absolute commodity prices between the two nations, which is the immediate cause of trade.(b) The Heckscher-Ohlin theory (sometimes referred to as the modern theory – asopposed to the classical theory - of international trade) assumes that nations have the same tastes, use the same technology, face constant returns to scale (i.e., a givenpercentage increase in all inputs increases output by the same percentage) but differ widely in factor endowments. It also says that in the face of identical tastes or demand conditions, this difference in factor endowments will result in a difference in relative factor prices between nations, which in turn leads to a difference in relativecommodity prices and trade. Thus, in the Heckscher-Ohlin theory, the internationaldifference in supply conditions alone determines the pattern of trade. To be noted is that the two nations need not be identical in other respects in order for internationaltrade to be based primarily on the difference in their factor endowments.(c) The Heckscher-Ohlin theorem postulates that each nation will export the commodityintensive in its relatively abundant and cheap factor and import the commodityintensive in its relatively scarce and expensive factor. As an important corollary, itadds that under highly restrictive assumptions, trade will completely eliminate thepretrade relative and absolute differences in the price of homogeneous factors amongnations. Under less restrictive and more usual conditions, however, trade will reduce, but not eliminate, the pretrade differences in relative and absolute factor prices among nations. In any event, the Heckscher-Ohlin theory does say something very useful onhow trade affects factor prices and the distribution of income in each nation. Classical economists were practically silent on this point.4. Suppose that tastes change in Nation 1 (the L-abundant and L-cheap nation) so that consumers demand more of commodity X (the L-intensive commodity) and less of commodity Y (the K- intensive commodity). Suppose that Nation 1 is India, commodity X is textiles, and commodi- ty Y is food. Starting from the no-trade equilibrium position and using the Heckscher-Ohlinmodel, trace the effect of this change in tastes on India's (a) relative commodity prices anddemand for food and textiles, (b) production of both commodities and factor prices, and(c) comparative advantage and volume of trade. (d) Do you expect international trade to leadto the complete equalization of relative commodity and factor prices between India and theUnited States? Why?Ans. (a) The change in tastes can be visualized by a shift toward the textile axis in India'sindifference map in such a way that an indifference curve is tangent to the steepersegment of India's production frontier (because of increasing opportunity costs) after the increase in demand for textiles. This will cause the pretrade relative commodity price of textiles to rise in India.(b) The increase in the relative price of textiles will lead domestic producers in India toshift labor and capital from the production of food to the production of textiles. Since textiles are L-intensive in relation to food, the demand for labor and therefore the wage rate will rise in India. At the same time, as the demand for food falls, thedemand for and thus the price of capital will fall. With labor becoming relative more expensive, producers in India will substitute capital for labor in the production of both textiles and food.(c) Even with the rise in relative wages and in the relative price of textiles, India stillremains the L-abundant and low-wage nation with respect to a nation such as theUnited States. However, the pretrade difference in the relative price of textilesbetween India and the United States is now somewhat smaller than before the change in tastes in India. As a result the volume of trade required to equalize relativecommodity prices and hence factor prices is smaller than before. That is, India need now export a smaller quantity of textiles and import less food than before for therelative price of textiles in India and the United States to be equalized. Similarly, the gap between real wages and between India and the United States is now smaller and can be more quickly and easily closed (i.e., with a smaller volume of trade).(d) Since many of the assumptions required for the complete equalization of relativecommodity and factor prices do not hold in the real world, great differences can be expected and do in fact remain between real wages in India and the United States.Nevertheless, trade would tend to reduce these differences, and the H-O model does identify the forces that must be considered to analyze the effect of trade on thedifferences in the relative and absolute commodity and factor prices between Indiaand the United States.5. (a) Explain why the Heckscher-Ohlin trade model needs to be extended. (b) Indicate in what important ways the Heckscher-Ohlin trade model can be extended. (c) Explain what ismeant by differentiated products and intra-industry trade.Ans. (a) The Heckscher-Ohlin trade model needs to be extended because, while generallycorrect, it fails to explain a significant portion of international trade, particularly the trade in manufactured products among industrial nations.(b) The international trade left unexplained by the basic Heckscher-Ohlin trade model canbe explained by (1) economies of scale, (2) intra-industry trade, and (3) trade based on imitation gaps and product differentiation.(c) Differentiated products refer to similar, but not identical, products (such as cars,typewriters, cigarettes, soaps, and so on) produced by the same industry or broadproduct group. Intra-industry trade refers to the international trade in differentiated products.。

Ch04罪犯劳动管理的特点及其岗位要求(精)






学习任务一 学习任务二 学习任务三
罪犯动管理对象的特点 罪犯劳动管理岗位的职责 罪犯劳动管理岗位的要求
主讲人:程玉敏
副教授
一、罪犯劳动管理对象的特点
(一)当前在押犯成分多元化 20世纪80、90年代罪犯构成特点: “三盲”(文盲、法盲、和 流氓), “三多”(贫者多、青年多、短期多),“三化” (低文化、低龄化、农村化)。 现在罪犯构成特点: 从罪犯案情上看,暴力加剧,作案手段残暴;团伙罪犯、涉黑涉恶 突出;邪教组织漫延,毒品犯罪严重。 从罪犯的文化、年龄、住地、职业看,文化程度高,年龄大,智能 型犯罪和职业犯罪相对增多。 从罪犯刑期看,刑期长、二进宫以上累犯、团伙犯增多。 这些构成变化使改造对象自身的心态、思想、行为向畸形冲动恶 变,具有极强报复性、突发性、纠合性、欺骗性和两面性,改造 难度加大,安全隐患较多。

(五)劳动力队伍极不稳定

1.劳动力数量、质量不稳定。 2.劳动力熟练程度和操作技术上的不稳定性。
学习任务二 罪犯劳动管理岗位的职责
“把墙内的人改造好,让墙外的人生活好, 这就是我们的职责” ——梅州监狱警察
监狱人民警察职权的内容
1.执行刑罚权 2.管理监狱权

收监权。 警戒隔离带的设置权。 戒具使用权。 武器使用权。 罪犯来往信件检查权。 对罪犯的考核权。 对罪犯的行政奖惩权。

(四)劳动力结构不合理 社会普通企业是围绕生产配置劳动力的,随时可以根据 企业的生产经营需要对劳动力结构进行调整,以确保其 合理性。

监狱的生产劳动是围绕执行刑罚,惩罚与改造罪犯这个 职能组织的。监狱生产的劳动力来源完全由社会打击犯 罪情况决定。
劳动力结构由监狱收押的罪犯结构决定。监狱劳动力思 想行为结构、数量质量结构、文化技术结构,年龄结构, 性格气质结构不可能按一般生产劳动需要进行主动的科 学配置,因此呈现不合理状况。

CH04 存储系统

CH04 存储系统习题与思考题1.存储器的哪一部分用来存储程序指令及像常数和查找表一类的固定不变的信息?哪一部分用来存储经常改变的数据?解答:只读存储器ROM;随机存储器RAM。

2.术语“非易失性存储器”是什么意思?PROM和EPROM分别代表什么意思?解答:“非易失性存储器”是指当停电后信息会丢失;PROM--可编程序的只读存储器PROM(Programmable ROM),EPROM--可擦除的可编程的只读存储器EPROM(Erasible Programmable ROM)。

3.微型计算机中常用的存储器有哪些?它们各有何特点?分别适用于哪些场合?解答:(略)4.现代计算机中的存储器系统采用了哪三级分级结构,主要用于解决存储器中存在的哪些问题?解答:目前在计算机系统中通常采用三级存储器结构,即使用高速缓冲存储器、主存储器和辅助存储器,由这三者构成一个统一的存储系统。

从整体看,其速度接近高速缓存的速度,其容量接近辅存的容量,而位成本则接近廉价慢速的辅存平均价格。

三级结构主要用于解决速度、容量和成本的问题。

5.试比较静态RAM和动态RAM的优缺点,并说明有何种方法可解决掉电时动态RAM中信息的保护。

解答:静态RAM----存储一位信息的单元电路可以用双极型器件构成,也可用MOS器件构成。

双极型器件构成的电路存取速度快,但工艺复杂,集成度低,功耗大,一般较少使用这种电路,而采用MOS器件构成的电路。

静态RAM的单元电路通常是由6个MOS 管子组成的双稳态触发器电路,可以用来存储信息“0”或者“1”,只要不掉电,“0”或“1”状态能一直保持,除非重新通过写操作写入新的数据。

同样对存储器单元信息的读出过程也是非破坏性的,读出操作后,所保存的信息不变。

使用静态RAM的优点是访问速度快,访问周期达20~40ns。

静态RAM工作稳定,不需要进行刷新,外部电路简单,但基本存储单元所包含的管子数目较多,且功耗也较大,它适合在小容量存储器中使用。

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Equipment Machinery Buildings Land
LO 2
Current Liabilities
Liabilities that will be due within a short time (usually one year or less) and that are to be paid out of current assets are called current liabilities.
LOce Sheet
A classified balance sheet is a balance sheet that was expanded by adding subsections for current assets; property, plant, and equipment; current liabilities; and long-term liabilities.
(concluded)
LO 1
Flow of Accounting Information
LO 1
Flow of Accounting Information
4-1
TRUE/FALSE A net loss is shown on the work sheet in the credit columns of both the Income Statement columns and the Balance Sheet columns.
ANSWER D
4-1
MULTIPLE CHOICE
A net loss appears on the work sheet in the
A debit column of the Balance Sheet columns B credit column of the Balance Sheet columns C debit column of the Income Statement columns D credit column of the Adjustments columns
Learning Objective 3
LO 2
Fixed Assets
Property, plant, and equipment (also called fixed assets or plant assets) include assets that depreciate over a period of time. Land is an exception, as it is not subject to depreciation.
Accounts payable Wages payable Interest payable Unearned fees
LO 2
Long-Term Liabilities
Liabilities not due for a long time (usually more than one year) are called long-term liabilities.
LO 2
Statement of Owner’s Equity
The first item presented on the statement of owner’s equity is the balance of the owner’s capital account at the beginning of the period.
Completing the Accounting Cycle
ACCOUNTING Chapter 4
Warren Reeve Fess
Learning Objective 1
1. Describe the flow of accounting information from the unadjusted trial balance into the adjusted trial balance and financial statements.
(continued)
LO 1
Flow of Accounting Information
End-of-Period Spreadsheet (Work Sheet)
Unadjusted TB Adjustments Adjusted TB
Accounts
Dr
Cr
Dr
Cr
Dr
Cr
Adjustments are combined with the trial balance amounts. Account balances are now adjusted. (continued)
LO 1
Flow of Accounting Information
LO 1
Flow of Accounting Information
End-of-Period Spreadsheet (Work Sheet)
Unadjusted TB Adjustments Adjusted TB
Accounts
Cash Accounts Receivable Notes Receivable Supplies
LO 2
Notes Receivable
Notes receivable are written promises by the customer to pay the amount of the note and possibly interest at an agreed rate.
LO 2
Balance Sheet
The balance sheet is prepared directly from the Balance Sheet or Adjusted Trial Balance columns of the end-of-period spreadsheet (or work sheet), beginning with Cash of $2,065.
ANSWER True.
4-1
MULTIPLE CHOICE
The worksheet
A is an integral part of the accounting cycle B eliminates the need to rewrite the financial statements C is a working paper that is required D is used to summarize account balances and adjustments for the financial statements
End-of-Period Spreadsheet (Work Sheet)
Unadjusted TB Adjustments Adjusted TB
Accounts
Dr
Cr
Dr
Cr
Dr
Cr
Adjustments are entered here. Two possibilities:
Deferrals – Existing balances are changed Accruals – New information is entered
LO 2
Income Statement
The income statement is prepared directly from the Income Statement or Adjusted Trial Balance columns of the end-of-period spreadsheet (work sheet) beginning with fees earned of $16,840.
LO 1
Flow of Accounting Information
End-of-Period Spreadsheet (Work Sheet)
Adjusted TB Income State. Balance Sheet
Accounts
Dr
Cr
Dr
Cr
Dr
Cr
Revenue and expense balances in the Adjusted Trial Balance column are extended to the Income Statement column.
Dr
Cr
Dr
Cr
Dr
Cr
Account balances are listed in the Trial Balance column using the ending balances found in the general ledger. (continued)
LO 1
Flow of Accounting Information
(continued)
LO 1
Flow of Accounting Information
End-of-Period Spreadsheet (Work Sheet)
Adjusted TB Income State. Balance Sheet
Accounts
Dr
Cr
Dr
Cr
Dr
Cr
Asset, liability, owner’s equity, and drawing balances in the Adjusted Trial Balance column are extended to the Balance Sheet column.
ANSWER A
Learning Objective 2
1. Describe the flow of accounting information from the unadjusted trial balance into the adjusted trial balance and financial statements. 2. Prepare financial statements from adjusted account balances.
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