Female power

Female power

Across the rich world more women are working than ever before. Coping with this change will be one of the great challenges of the coming decades

THE economic empowerment of women across the rich world is one of the most remarkable revolutions of the past 50 years. It is remarkable because of the extent of the change: millions of people who were once dependent on men have taken control of their own economic fates. It is remarkable also because it has produced so little friction: a change that affects the most intimate aspects of people’s identities has been widely welcomed by men as well as women. Dramatic social change seldom takes such a benign form.

Yet even benign change can come with a sting in its tail. Social arrangements have not caught up with economic changes. Many children have paid a price for the rise of the two-income household. Many women—and indeed many men—feel that they are caught in an ever-tightening tangle of commitments. If the empowerment of women was one of the great changes of the past 50 years, dealing with its social consequences will be one of the great challenges of the next 50.

At the end of her campaign to become America’s first female president in 2008, Hillary Clinton remarked that her 18m votes in the D emocratic Party’s primaries represented 18m cracks in the glass ceiling. In the market for jobs rather than votes the ceiling is being cracked every day. Women now make up almost half of American workers (49.9% in October). They run some of the world’s bes t companies, such as PepsiCo, Archer Daniels Midland and W.L. Gore. They earn almost 60% of university degrees in America and Europe.

Progress has not been uniform, of course. In Italy and Japan employment rates for men are more than 20 percentage points higher than those for women (see chart 1). Although Italy’s female employment rate has risen markedly in the past decade, it is still below 50%, and more than 20 percentage points below those of Denmark and Sweden (chart 2). Women earn substantially less than men on average and are severely under-represented at the top of organisations.

The change is dramatic nevertheless. A generation ago working women performed menial jobs and were routinely subjected to casual sexism—as “Mad Men”, a television drama a bout advertising executives in the early 1960s, demonstrates brilliantly. Today women make up the majority of professional workers in many countries (51% in the United States, for example) and casual sexism is for losers. Even holdouts such as the Mediterranean countries are changing rapidly. In Spain the proportion of young women in the labour force has now reached American levels. The glass is much nearer to being half full than half empty.

What explains this revolution? Politics have clearly played a part. Feminists such as Betty Friedan have demonised domestic slavery and lambasted discrimination. Governments have passed equal-rights acts. Female politicians such as Margaret Thatcher and Mrs Clinton have taught younger women that anything is possible. But politics is only part of the answer: such discordant figures as Ms Friedan and Lady Thatcher have been borne aloft by subterranean economic and technological forces.

The rich world has seen a growing demand for women’s labour. When brute strength mat tered more than brains, men had an inherent advantage. Now that brainpower has triumphed the two sexes are more evenly matched. The feminisation of the workforce has been driven by the relentless rise of the service sector (where women can compete as well as men) and the equally relentless decline of manufacturing (where they could not). The landmark book in the rise of feminism was arguably not Ms Friedan’s “The Feminine Mystique” but Daniel Bell’s “The Coming of Post-Industrial Society”.

Demand has been matched by supply: women are increasingly willing and able to work outside the home. The vacuum cleaner has played its part. Improved technology reduced the amount of time needed for the traditional female work of cleaning and cooking. But the most important innovation has been the contraceptive pill. The spread of the pill has not only allowed women to get married later. It has also increased their incentives to invest time and effort in acquiring skills, particularly slow-burning skills that are hard to learn and take many years to pay off. The knowledge that they would not have to drop out of, say, law school to have a baby made law school more attractive.

The expansion of higher education has also boosted job prospects for women, improving their value on the job market and shifting their role models from stay-at-home mothers to successful professional women. The best-educated women have always been more likely than other women to work, even after having children. In 1963, 62% of college-educated women in the United States were in the labour force, compared with 46% of those with a high school diploma. Today 80% of American women with a college education are in the labour force compared with 67% of those with a high school diploma and 47% of those without one.

This growing cohort of university-educated women is also educated in more marketable subjects. In 1966, 40% of American women who received a BA specialised in education in college; 2% specialised in business and management. The figures are now 12% and 50%. Women only continue to lag seriously behind men in a handful of subjects, such as engineering and computer sciences, where they earned about one-fifth of degrees in 2006.

One of the most surprising things about this revolution is how little overt celebration it has engendered. Most people welcome the change. A recent Rockefeller Foundation/Time survey found that three-quarters of Americans regarded it as a positive development. Nine men out of ten said they were comfortable with women earning more than them. But few are cheering. This is partly because young women take their opportunities for granted. It is partly because for many women work represents economic necessity rather than liberation. The rich world’s growing army of single mothers have little choice but to work. A growing proportion of married women have also discovered that the only way they can preserve their households’ living standards is to join their husbands in the labour market. In America families with stay-at-home wives have the same inflation-adjusted income as similar families did in the early 1970s. But the biggest reason is that the revolution has brought plenty of problems in its wake.

Across the rich world more women are working than ever before. Coping with this change will be one of the great challenges of the coming decades

在发达国家，比以往更多的女性正在工作。应对这一变化这将是今后几十年面临的重大挑战之一。

THE economic empowerment of women across the rich world is one of the most remarkable revolutions of the past 50 years. It is remarkable because of the extent of the change: millions of people who were once dependent on men have taken control of their own economic fates. It is remarkable also because it has pro duced so little friction: a change that affects the most intimate aspects of people’s identities has been widely welcomed by men as well as women. Dramatic social change seldom takes such a benign form.

发达国家女性的经济赋权是过去五十年中最引人注目的革命之一。它引人注目是因为变革的程度：成千上万曾经依靠男人的女人们掌握了自己的经济命运。还因为它几乎没怎么产生摩擦：一个影响人身份最本质方面的变革受到男人们和女人们的普遍欢迎。巨大的社会变革很少能有这样温和的形式。

Yet even benign change can come with a sting in its tail. Social arrangements have not caught up with economic changes. Many children have paid a price for the rise of the two-income household. Many women—and indeed many men—feel that they are caught in an ever-tightening tangle of commitments. If the empowerment of women was one of the great changes of the past 50 years, dealing with its social consequences will be one of the great challenges of the next 50.

但即使温和的变革也可以有带刺的尾巴。社会配置没有跟上经济变化。许多孩子为双收入家庭的增加付出了代价。很多女性-事实上还有很多男性-觉得自己被缠绕在一个越来越紧的“义务”线团之中。如果说女性赋权是过去50年中最伟大的变革之一，那么应对其带来的社会效应将是今后50年最巨大的挑战之一。

At the end of her campaign to become America’s first female president in 2008, Hillary Clinton remarked that her 18m votes in the Democratic Party’s primaries represented 18m cracks in the glass ceiling[1]. In the market for jobs rather than votes the ceiling is bei ng cracked every day. Women now make up almost half of American workers (49.9% in October). They run som e of the world’s best companies, such as PepsiCo, Archer Daniels Midland and W.L. Gore. They earn almost 60% of university degrees in America and Europe.

在希拉里克林顿竞选美国首位女性总统的运动结束时，她评论说她的一千八百万民主党党内初选选票代表了玻璃天花板的一千八百万次粉碎。而每天在被打破着的，是工作机会的玻璃天花板。女性几乎占了当今美国劳动力的半数（十月：49.9%）。她们领导着一些世界最好的公司，比如百事可乐，阿彻丹尼斯米德兰（AMD）和戈尔公司（W.L. Gore）。在美国和欧洲，大约60%的大学学位由女性获得。

Progress has not been uniform, of course. In Italy and Japan employment rates for men are more than 20 percentage points higher than those for women (see chart 1). Although Italy’s female employment rate has risen markedly in the past decade, it is still below 50%, an d more than 20 percentage points below those of Denmark and Sweden (chart 2). Women earn substantially less than men on average and are severely under-represented at the top of organisations.

当然，进程不可能是一致的，在意大利和日本，男性的就业率比女性高出20多个百分点（见图1）。虽然意大利的女性就业率在过去十年中显著增长，但却仍然低于50%，比丹麦和瑞典低了二十多个百分点（见图2）。女性平均比男性挣得少很多，并且在组织高层所占席位极少。

The change is dramatic nevertheless. A generation ago working women performed menial jobs and were routinely subjected to casual sexism—as “Mad Men”, a television drama about advertising executives in the early 1960s, demonstrates brilliantly. Today women make up the majority of professional workers in many countries (51% in the United States, for example) and casual sexism is for losers. Even holdouts such as the Mediterranean countries are changing rapidly. In Spain the proportion of young women in the labour force has now reached American levels. The

glass is much nearer to being half full than half empty.

不过变革仍然是剧烈的。30年以前，职业女性干的只是些粗活，并且总是会被“不经意的歧视”-“广告狂人”，一部关于1960年代广告人的美剧，很好的诠释了这点。如今，女性占专业人员的大半部分（比如在美国占了51%），而只有那些失败者才会“不经意的歧视”（女性）。即使是顽固的地中海国家们也在迅速的变化着。在西班牙，年轻女性占劳动力的比例已与美国相当，差不多已经大于了一半。

What explains this revolution? Politics have clearly played a part. Feminists such as Betty Friedan have demonised domestic slavery and lambasted discrimination. Governments have passed equal-rights acts. Female politicians such as Margaret Thatcher and Mrs Clinton have taught younger women that anything is possible. But politics is only part of the answer: such discordant figures as Ms Friedan and Lady Thatcher have been borne aloft by subterranean economic and technological forces.

是什么造成了这场革命？政治很明显起了一定作用。贝蒂?弗里丹这样的女权主义者妖魔化了“家务奴隶”并狠狠的鞭笞了性别歧视。政府们通过了权利平等法案。玛格丽特?撒切尔和希拉里?克林顿这样的女政治家教会了年轻女孩们“万事皆有可能”。但政治只是部分因素：像弗里丹和撒切尔夫人这样的“离经叛道者”其实是被经济和技术力量的暗涌推到风口浪尖的。

The rich world has seen a growing demand for women’s labour. When brute strength mattered more than brains, men had an inherent advantage. Now that brainpower has triumphed the two sexes are more evenly matched. The feminisation of the workforce has been driven by the relentless rise of the service sector (where women can compete as well as men) and the equally relentless decline of manufacturing (where they could not). The landmark book in the rise of feminism was arguably not Ms Friedan’s “The Feminine Mystique” but Daniel Bell’s “The Coming of Post-Industrial Society”.

发达国家对女性劳动力的需求见长。在蛮力比脑力重要的年代，男人有天生的优势。而今由于脑力占优势，两性的实力更相当了。服务业（在此行业，女性可与男性竞争）的迅猛增长和制造业（在此行业，女性无法与男性抗衡）同样迅猛的衰落推动了劳动力的女性化。也许女权主义兴起的里程碑式的书籍不是弗里丹女士的《女性迷思》，而可能是丹尼尔?贝尔的《后工业社会的来临》。

Demand has been matched by supply: women are increasingly willing and able to work outside the home. The vacuum cleaner has played its part. Improved technology reduced the amount of time needed for the traditional female work of cleaning and cooking. But the most important innovation has been the contraceptive pill. The spread of the pill has not only allowed women to get married later. It has also increased their incentives to invest time and effort in acquiring skills, particularly slow-burning skills that are hard to learn and take many years to pay off. The knowledge that they would not have to drop out of, say, law school to have a baby made law school more attractive.

需求和供给得以匹配：女性更愿意并更能外出工作了。吸尘器起到了作用。改进的技术减少了打扫和烹饪等传统女性家务的所需时间。但最重要的创新是避孕药。避孕药的推广不光使女性可以更晚结婚，还增加了她们在获得技能，特别是那些难学、又要很多年才有成效的“慢性”技能上投资时间和努力的动因。比方说，女性们要是知道她们没有必要为了生小孩而从法律学院辍学，那法学院对她们就更有吸引力了。

The expansion of higher education has also boosted job prospects for women, improving their value on the job market and shifting their role models from stay-at-home mothers to successful professional women. The best-educated women have always been more likely than other women to work, even after having children. In 1963, 62% of college-educated women in the United States were in the labour force, compared with 46% of those with a high school diploma. Today 80% of American women with a college education are in the labour force compared with 67% of those with a high school diploma and 47% of those without one.

高等教育的普及也提升了女性的就业前景，提升了她们在就业市场上的价值，并且使她们的角色模型从全职妈妈变成了成功专业女性。接受最好教育的女性往往比一般女性更愿意工作，就算有了孩子也一样。1963年，62%的大学毕业女性在工作，而高中毕业的女性中，

这个数字只有46%。而如今的美国，这两个比率分别为80%和67%，而高中未毕业的女性中，这个数字为47%。

This growing cohort of university-educated women is also educated in more marketable subjects. In 1966, 40% of American women who received a BA specialised in education in college; 2% specialised in business and management. The figures are now 12% and 50%. Women only continue to lag seriously behind men in a handful of subjects, such as engineering and computer sciences, where they earned about one-fifth of degrees in 2006.

这群越来越多的大学毕业女性也选择了更畅销的专业。1966年，获得文科学士的女性中，40%主修教育专业，2%主修工商和管理学。如今这两个数字是12%和50%。女性只在少数专业上落后于男性，比如工程学和计算机科学，2006年这些专业女性只占1/5。

One of the most surprising things about this revolution is how little overt celebration it has engendered. Most people welcome the change. A recent Rockefeller Foundation/Time survey found that three-quarters of Americans regarded it as a positive development. Nine men out of ten said they were comfortable with women earning more than them. But few are cheering. This is partly because young women take their opportunities for granted. It is partly because for many women work represents economic necessity rather than liberation. The rich world’s grow ing army of single mothers have little choice but to work. A growing proportion of married women have also discovered that the only way they can preserve their households’ living standards is to join their husbands in the labour market. In America families with stay-at-home wives have the same inflation-adjusted income as similar families did in the early 1970s. But the biggest reason is that the revolution has brought plenty of problems in its wake.

最让人惊奇的事之一是这一革命引来的公开颂扬如此之少。大多数人欢迎这个变革，最近一次洛克菲勒基金会和时代杂志的调查显示，3/4的美国人认为这是一项积极的发展。10个男人里有9个声称不介意女性赚得比他们多，但很少有为此高兴的。这部分是因为许多年轻女性认为她们的机会是理所应当的。而这又部分是因为许多女性参与工作代表的是一种经济需求，而不是妇女解放。发达国家逐渐增加的单身妈妈群体必须选择工作。越来越多的已婚女性也发现保证家庭生活水平的唯一方法就是参加工作。在美国，全职太太家庭的通胀调整后收入仅相当于1970年代初期的同类水平。但最大的问题是，这场革命的尾流带来了许多问题

机械原理凸轮设计C

机械原理课程设计 说明书 题目：双联凸轮写“C”机构 学院：xxxxxxxxxxxxxxxxx 班级：xxxxxxxxxxxxx 姓名：xxxxxxxxxxx 学号：xxxxxxxxxxxxx 指导教师：xxxxxxxxx 2015年1月23日

一．设计任务…………………………………………二．原始数据设计及设计要求………………………三．设计方案分析……………………………………四．设计内容…………………………………………五．设计小结…………………………………………六．参考文献…………………………………………

一．设计任务 设计能写出英文字母C的凸轮写字机构。且该机构由两凸轮连续回转的协调配合及相应的连杆，控制绘图部件画出英文字母C。 二．原始数据设计及设计要求 1. C字高60mm(y方向)。 2. C字宽45mm(x方向)。 3. 机构体积小，质量轻，工作可靠，启动或停顿时冲击小。 三．设计方案分析 1. 方案一：两对心直动尖顶推杆盘形凸轮写字机构。 尖顶推杆虽然构造简单，但易磨损，且启动或停顿时冲击大。 2. 方案二：两对心直动滚子推杆盘形凸轮写字机构。 滚子与凸轮间为滚动摩擦，磨损小，传动精度高，冲击小。 3. 方案选择：通过对上述两种方案分析比较，选用方案二。

四、设计内容 目标C曲线 通过作图工具，得到想要的C曲线如下图所示 该“C”曲线为一段半径是30mm的圆弧的一部分。由于双联凸轮机构的特性，作出的曲线应为封闭图形。所以要用一条线段将“C”的首尾相连，即得到如图所示的曲线。

数据处理 通过建立如图所示的坐标系，得到X的相对偏移量和X=X(Φ)和Y的相对偏移量和Y=Y(Φ)。并建立如下的表格。

机械原理 凸轮机构设计

机械原理课程设计——凸轮机构设计（一） 目录 (1) ＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿（一）、题目及原始数据 (2) （二）、推杆运动规律及凸轮廓线方程 (3) （三）、计算程序方框图 (5) （四）、计算源程序 (6) （五）、程序计算结果及分析 (10) （六）、凸轮机构图 (15)

（七）、心得体会 (16) （八）、参考书 (16)

（一）、题目及原始数据 试用计算机辅助设计完成偏置直动滚子推杆盘形凸轮机构的设计，凸轮以 1rad/s的角速度沿逆时针方向转动。要求： （1）、推程运动规律为等加速等减速运动，回程运动规律为五次多项式运动规律； （2）、打印出原始数据； （3）、打印出理论轮廓和实际轮廓的坐标值； （4）、打印出推程和回程的最大压力角，以及出现最大压力角时凸轮的相应转角； （5）、打印出凸轮实际轮廓曲线的最小曲率半径，以及相应的凸轮转角； （6）、打印出凸轮运动的位移； （7）、打印最后所确定的凸轮的基圆半径。 原始数据如下： r0=0.015; 初选的基圆半径r0 Deltar0=0.0005; 当许用压力角或许用最小曲率半径不满足时，r0以Δr0 为步长增加重新计算 rr=0.010; 滚子半径r r h=0.028; 推杆行程h e=0.005; 偏距e omega=1; 原动件凸轮运动角速度，逆时针ω delta1=pi/3; 近休止角δ1 delta2=2*pi/3; 推程运动角δ2 delta3=pi/2; 远休止角δ3 delta4=pi/2; 回程运动角δ4 alpha1=pi/6; 推程许用压力角[α1] alpha2=(70/180)*pi; 回程许用压力角[α2] rho0min=0.3*rr; 许用最小曲率半径ραmin （二）、推杆运动规律及凸轮廓线方程 推杆运动规律： （1）近休阶段：0o≤δ<60 o s=0 v=0 a=0 （2）推程阶段：60o≤δ<180 o 等加速运动规律：60o≤δ<120 o s=2h(δ-60o)2/(120 o)2 v=4hω(δ-60o)/(120 o)2 a=4hω2/(120 o)2 等减速运动规律：120o≤δ<180 o

机械原理凸轮设计D

机械原理课程设计 说明书 设计题目：盘形凸轮写字机构D 工程机械xxxxxxxxxxxxxxxxx 设计者：xxxxxxxx

学号：xxxxxxxxxxx 指导教师：xxxxxxxxxxx 2015 年 1 月23 日一．设计任务 (1) 二．原始数据设计及设计要求 (1) 三．设计方案分析 (1) 四．设计容 (2) 五．设计小结 (6) 六．参考文献 (7)

一．设计任务 设计能写出英文字母D的凸轮写字机构。且该机构由两凸轮连续回转的协调配合及相应的连杆，控制绘图部件画出英文字母D。 二．原始数据设计及设计要求 1.D字高60mm(y方向)。 2.D字宽30mm(x方向)。 3.机构体积小，质量轻，工作可靠，启动或停顿时冲击小。 三．设计方案分析

1.方案一：两对心直动尖顶推杆盘形凸轮写字机构。 尖顶推杆虽然构造简单，但易磨损，且启动或 停顿时冲击大。 2.方案二：两对心直动滚子推杆盘形凸轮写字机构。 滚子与凸轮间为滚动摩擦，磨损小，传动精度 高，冲击小。 3.方案选择：通过对上述两种方案分析比较，选用方案二。取凸轮A的基圆半径R=50mm 凸轮A的理论廓线如图所示

取滚子半径r=3mm得凸轮A的实际廓线 取凸轮B的基圆半径r=50mm Φ /° 0 10 20 30 40 50 60 70 80 90 100 110 120 Y/m m 50.0 53.3 56.7 60.0 63.3 66.7 70.0 73.3 76.7 80.0 83.3 86.7 90.0 Φ /° 130 140 150 160 170 180 190 200 210 220 230 240 250 Y/m m 93.3 96.7 100. 103. 3 106. 7 110. 109. 5 108. 5 105. 9 102. 9 99.3 95.0 90.3

哈工大—机械原理凸轮大作业

一、题目要求及机构运动简图 如图1所示直动从动件盘形凸轮机构。其原始参数见表1。 图一凸轮运动简图 表一凸轮原始参数

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s= p1+p2p p>=p 1&&p

s

N Y ② N Y ① N ② s= 执行函数zuobiao （） p+5=>p p>=p 1+p 2+p 3/2&&p< s=

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线交于一点H’，以H’为圆心，BD的长度为半径作弧，与B的轨迹圆（大红圆）交于点BH，这里比较好理解，是根据BD的长度不变得来的。找出来BH点，如图所示的角BABh就是转到H点接触的转角。这是反转法求转角的基本方法，可以在凸轮廓线上找出任意两个不同接触点接触时的转角。容易出错的是B的轨迹圆，其圆心是滚子的回转中心，不是滚子的形心。（3） 推程角定义：推程角即从动件由离凸轮转动中心最近位置到达最远位置时相应的凸轮转角。回程角的大小等于360度减去推程角。要找出推程角，首先找出离凸轮转动中心最近和最远的位置，在图中分别为M点和N点。如第二题所说的方法，可以求出M和N对应的BM和BN。然后按照和凸轮转向相反的方向，由BM沿着B的轨迹圆（大红圆）转动到BN，这个角度就是推程角。推 程角和回程角表示时可以另外画出一个和轨迹圆（大红圆）同圆心的圆上表示，如图，一定写清楚，注意两个角都有箭头标注方向。 （4） 压力角，无论是在凸轮中还是在四杆机构中都是最难的。先确定压力角的定义。首先，压力角是针对从动件而言，比如在以曲柄为主动件的曲柄摇杆中摇杆是从动件。这个题，从动件上貌似有一个滚子，但是这个和普通滚子是不同的，这个是相对固定的死的，从动件是包括这个小圆在内，而普通的滚子，也就是能相对转动的滚子，不属于从动件。简单了说 就是这个小圆如果不能转，从动件指的就是构件BC（C为动点），如果能转，从动件指的就是不含小圆的BD杆。2009的从动件指的是构件2，而不是提供恒定重力的重块。从动件的运动方向是垂直于从动件的，如果小圆能转，其运动方向是垂直于直线BD，如果小圆不能转也就是本题中的情况，从动件的运动方向是垂直于B到接触点的连线即直线BC的。从动件不一样直接影响到压力角。2006的凸轮压力角也是这样，从动件的运动方向垂直于B到接触点的连线。受力方向是在过接触点的半径方向。这样压力角就找到，

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机械原理凸轮设计D 公司内部档案编码：[OPPTR-OPPT28-OPPTL98-OPPNN08]

机械原理课程设计 说明书 设计题目：盘形凸轮写字机构D 工程机械 xxxxxxxxxxxxxxxxx 设计者：xxxxxxxx 学号：xxxxxxxxxxx 指导教师：xxxxxxxxxxx

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取凸轮A的基圆半径R=50mm Φ /°0102030405060708090100110120 X/mm Φ /°130140150160170180190200210220230240250 X/mm Φ /°260270280290300310320330340350360 X/mm 凸轮A的理论廓线如图所示 取滚子半径r=3mm得凸轮A的实际廓线

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H=110 ,05 6φπ = B.推杆回程方程： 当13π/12 ≤φ≤59π/36 时，有： 2 345222221 222'02 21222' 0[1(10156)] 30(12)60(132) s h T T T h v T T T h a T T T ωφωφ=--+=- -+=- -+ 式中 () 02' 0s T ?φφφ-+= h=110 056 φπ= ' 05 9φπ= ?s =5π/9 2、推杆位移,速度,加速度线图如下（用matlab 编程得）： A 、推杆位移线图 clear clc x1=linspace(0,5*pi/6,300); x2=linspace(5*pi/6,13*pi/12,300); x3=linspace(13*pi/12,59*pi/36,300); x4=linspace(59*pi/36,2*pi,300); t1=x1/(5*pi/6) s1=110*(10*t1.^3-15*t1.^4+6*t1.^5); s2=110; t2=9*x3/(5*pi)-39/20; s3=110*(1-(10*t2.^3-15*t2.^4+6*t2.^5)); s4=0; plot(x1,s1,'k',x2,s2,'k',x3,s3,'k',x4,s4,'k') ; xlabel('角度/rad'); ylabel('位移s/mm'); title('推杆位移线图'); grid;