用初等方法研究函数y=x+1/x的性状

函数y=x 1/x是沟通平均值不等式与函数的桥梁。研究清楚其性状,在高中数学教学中有一定的必要性。1.极值点:当x∈(0, ∞)时,由平均值不等式有:x 1/x≥2,当且仅当x=1/x即x=1时等号成立。从而点(1,2)为函数在(0, ∞)上的极小值点。又y=x 1/x为奇函数,从而点(-1,-2)为函数在(-∞,0     

题词

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论知识资本参与下社会总产品的实现条件

知识资本在 19世纪至 2 0世纪开始形成 ,它的参与对社会资本的扩大再生产带来了新的变化 ,并产生了生产社会发展资料的部类Ⅲ ,这时社会总资本简单再生产的实现条件 ,用公式表示为 :Ⅰ (z +y +m) =Ⅱc +Ⅲ (c +v +m)。在不追加实物资本及劳动力的情况下扩大再生产的社会总产品实现条件是 :Ⅰ (z +Δz +mx) =Ⅱ (c -Δc) +Ⅲ (c -Δc)。     

例谈a3+b3+c3=3abc的解题功能

众所周知：a3 c3-3abc=1/2(a b c)[(a-b)2 (b-c)2 (c-a)],当a b c =0或a=b=c时,a3 b3 c3=3abc.其中a b c=0时,a3 b3 c3=3abc(以下称为定理)在中学数学中有一定的解题辅助功能。     

内增高鞋印对身高分析的影响及其改进方法

随着内增高鞋被人们越来越广泛接受,内增高鞋印在案发现场的出现也愈来愈多。常用的身高计算方法是基于赤足或平底鞋长度进行的,对内增高鞋印进行身高分析时易产生较大的误差。为避免这种误差,可采用局部特征比例反映身高的方法,即利用第一跖骨头与第五跖骨头之间的距离计算人身身高,公式为:y=7x/9%=77.8x。或利用跖压内缘凸点与拇趾压痕前缘凸点距离计算人身身高,公式为:y=7x/27.56%=25.4x。     

一个不等式的七种证明方法

高中数学第二册(上)P16页练习2:求证:ac bd≤[(a~2 b~2)(c~2 d~2)]~1/2说明:这个不等式就是著名的柯西不等式。在高中数学中,它有很多的应用。下面先看它的证明。这个习题有很多种证明方法,讲透这几种方法对于学生理解和掌握不等式的证明方法有很大的帮助。分析一:用分析法证法     

低持新菪畏从Τ赜杉す獾窨袒诰奂谆┧峒柞?

×40×3 mm)上雕刻而成。在实验所建立的最佳条件下,该方法在2.0×10-7~1.0×10-5g/mL范围内化学发光的降低值与四环素的质量浓度具有好的线性关系,检出限为1.7×10-8g/mL,相对标准偏差为1.7%(n=11,ρ=5.0×10-7g/mL),检测结果满意。Determination of Tetracycline in Fish and Shrimp by Chemilumines     

奢而无信?

一套红木家具的价格=一辆劳斯莱斯+一辆兰博基尼+一辆法拉利+两架私人飞机。2007中国(温州)国际奢侈品展,6800万元的海南黄花梨家具独领风骚。而此次展会的盛况,     

困境与出路:人的安全与江西农村经济发展的平衡——基于人的安全理论维度

农村经济在快速发展,留守儿童的人身安全问题也越来越突出,两者出现了一种失衡现象,一种近乎"1+1=0"的"零和"现象。为了在两者间寻求一种平衡,实现"双赢"(即:既要保证经济的发展,又要确保农村留守儿童的人身安全),笔者以江西农村(经济、留守儿童人身安全)为研究对象,尝试从人的安全理论维度探究两者间的平衡点。     

34项重大农业科技成果推广概览(1978—1989)

推广_项g杂交水稻地膜覆盖栽培技术推广时间1 976一19891 982一1989累计推广数撇 14亿亩 1.84亿亩累耀朴亿公和700多280多配方施肥技术水稻病虫害综合防治技术棉花优质高产综合技术马铃薯无毒种薯生产技术稻田稻萍鱼综合丰产技术1985一19881 983一t9861 986一19881978一毛9891 987一198916亿多亩2。66亿亩3659万亩2200万亩268万亩7 .99公斤/亩250公斤/亩(鲜薯)水稻略增产鲜萍15。。公斤/亩鱼30一40公斤/亩12 .2公斤/亩可减少损失50多亿元2。775540。20.9381。83(鲜萍)(鲜鱼)单双低油菜高产保优及配套技术旱地甘蔗高产综合栽培技术塑料棚蔬菜…     

Neither the T Index nor the D2 Score Measure “Two-Partyness”: A Comment on Gaines and Taagepera

This comment critiques the paper by Gaines and Taagepera (2013 Gaines, Brian J. &; Taagepera, Rein (2013) How to operationalize “two partyness”, Journal of Elections, Public Opinion and Parties. Digital online version, available at <http://dx.doi.org/10.1080/17457289.2013.770398> (accessed 23 March 2013). [Google Scholar]) outlining two new measures that compare how far election outcomes diverge from a particular ideal of “perfect two-partyness” (one in which all votes are divided equally between the top two parties). Their first proposed T index is an unstable amalgam of two different measures, one linear and the other not. Applied to analysing sets of election outcomes, it systematically mis-signals “two-partyness” in its accepted meaning, producing perverse results. Their second index, D₂, has a varying minimum size level depending on the size of the largest party (P₁) and the number of observable parties competing. In many circumstances D₂ scores bifurcate – the same scores are produced by both very low and very high P₁ levels. Applied to distributions, the D₂ score artefactually homogenizes very dissimilar distributions, again misreads even two-party configurations, and always overstates “two-partyness” in multi-party systems. I conclude that neither the T nor D₂ indices are fit for purpose. They should not be further used in electoral analysis.     

Political rationality reconsidered: Notes on an integrated evaluative scheme for policy choices

This essay deals with the concept and problem of political rationality. Following the ancient conception that the absence or presence of rationality manifests itself in choice situations, we try to explore at first the specific characteristics of political choice, then turn to a discussion of the criteria for rationality, considering process, goal contents and structure criteria, point to the restrictions for rationality analytically inherent in any choice structure, and try in the end to make clear the difference between these analytical (i.e. principally unremovable) restrictions and the (principally removable) confining conditions (Kirchheimer) for rational political choices provided by the circumstances of present-day politics.     

The Purpose and Perception of Learning Objectives

Much of existing assessment and instructional design strategies revolve around the use of learning objectives. Learning objectives are used by faculty, by instructional designers, by accreditors, by assessment offices, and by students. But even as the use of learning objectives becomes more widespread, the definition and purpose have remained unclear. Instructional designers argue that learning objectives exist to provide a focused mindset for students engaging in the content, while faculty often view learning objectives as an administrative requirement that has little impact on teaching or student performance. Existing research on the subject is primarily normative and/or qualitative in nature (Harden 2002 Harden, Ronald M. 2002. “Learning Outcomes and Instructional Objectives: Is There a Difference?” Medical Teacher 24 (2):151–155.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]; Torrance 2007 Torrance, Harry. 2007. “Assessment as Learning? How the Use of Explicit Learning Objectives, Assessment Criteria and Feedback in Post-Secondary Education and Training Can Come to Dominate Learning.” Assessment in Education 14 (3):281–94. doi:10.1080/09695940701591867.[Taylor &; Francis Online] , [Google Scholar]). In this article, the researchers seek to use empirical evidence to examine the definitions, purpose, and impact of learning objectives on student performance. We find that there is no shared understanding of definitions and purpose, and using an experimental design, we find that learning objective wording and use in the classroom does not affect student performance.     

Implicit theories in policy discourse: An inquiry into the interpretations of reality in German technology policy

Interpretations of reality are an important, sometimes even decisive, dimension of the policy process. This essay seeks to demonstrate this point in the field of technology policy. Empirical research shows that government support for technology transfer in Germany is based on a concept of technology that is shared by neither companies nor academic researchers. These different concepts become reified interpretations of what technology means. They are referred to here as implicit theories. Interviews with academic researchers and business people demonstrate how inquiries into the realm of policy theories can be carried out.     

Policy analysis: some observations on the West German scene

The article provides an overview on the development and the state of policy analysis as applied public policy research in West Germany. The developmental sketch shows that, similar to the upsurge of policy research in the United States since the mid-1960s, policy research in the Federal Republic of Germany is an offspring of the reformist period of the late 1960s and early 1970s, carried by a virtual reformers' coalition among politicians, bureaucrats, and researchers. Due to extradisciplinary demands and also intradisciplinary shifts in research foci, public policy research became almost a growth industry in the course of the 1970s.The article goes on to explore which repercussions the economic crisis, the new conservative moods and majorities and the end to reforms has had on the state and the orientation of policy analysis. The argument is presented that, no matter which majorities have the day, policy research remains socially and politically indispensible to detect and test corridors and niches for public action under ever narrower financial restraints and to identify the costs and benefits of such policies in a changing world.     

Prolegomena to policy sciences

Establishment of policy sciences as a new supradiscipline involves a scientific revolution, requiring fargoing innovations in basic paradigms. Particularly essential are: (1) Integration between various disciplines, and especially of social sciences with analytical decision approaches; (2) bridging of the pure vs. applied dichotomy; (3) acceptance of tacit knowledge as a scientific resource; (4) changes in interface between science and values; (5) broad time perspectives; (6) focus on metapolicies; (7) commitment to policymaking improvement; and (8) concern with extrarational and irrational processes, such as creativity.Unique subjects of policy sciences, opened up by these paradigms, include, among others: (a) Policy analysis, which involves critical changes in systems analysis so as to permit application to complex policy issues; (b) policy strategies, involving determination of postures and main guidelines for specific policies, such as on degrees of incrementalism vs. innovation and on attitudes to risks; and (c) policymaking system redesign, including evaluation and improvement of the policymaking system, e.g., through changes in one-person-centered high-level decisionmaking, development of politicians, and institutionalization of social experimentation.Development of policy sciences requires many innovations in research, teaching, and professional activities. It constitutes a main effort to reconstruct the role of intellectualism and rationality in human affairs and, therefore, justifies intense efforts.Parts of this article are based on papers delivered at the 136th Annual Meeting of the American Association for the Advancement of Science (Boston, 26–31 December 1969) and at the 65th Annual Meeting of the American Political Science Association (New York, 2–6 September 1969).     

Wildavsky on budget reform

A large part of the literature on budgeting in the United States is concerned with reform. The goals of proposed reforms are couched in similar language - economy, efficiency, improvement, or just better budgeting ... However, any effective change in budgetary relationships must necessarily alter the outcomes of the budgetary process. Otherwise, why bother? Far from being a neutral matter of better budgeting, proposed reforms inevitably contain important implications for the political system, that is, the who gets what of governmental decisions (Wildavsky, 1961: p. 186). ... budgeting is a subsystem of politics, not vise versa - because of the current tendency to overload budgeting. As much as I respect the importance of budgeting and the talents of budgeteers, to substitute budgeting for governing will not work (Wildavsky, 1992b: p. 439).     

The war on poverty: between economics and politics

A wealth of solutions to poverty have been proposed, with little understanding of the forces required to turn a sound idea into an implementable program. A system approach is suggested to overcome this deficiency. This implies analyzing the effects of antipoverty measures on other elements of a society and a polity and the feedback effects of changes in these other elements on the new programs which are being introduced. Such an approach is seen overcoming the limitations of fragmented views of the issue—such as the purely economic one—as well as the lack of systematic analysis of a progam's costs, benefits, sources of funds, and nonfinancial resources. Consequently, a challenge is also offered to those who formulate programs without taking into account dominant values (e.g., questions of consensus) and other political considerations (e.g., which groups would benefit or suffer from the program). This is seen as leading to undemocratic action or, most frequently, to inaction due to resistance. The article concludes with a brief review of the recent Nixon-Moynihan proposal in terms of the societal-system approach here advocated, and adds a cautionary note on the limits of planning.In revising this article, I benefited from comments by Daniel Bell, Carolyn O. Atkinson, and Sarajane Heidt.     

Fair treatment,fair play? The relationship between fair treatment perceptions,political trust and compliant and cooperative attitudes cross-nationally

Obtaining citizens’ voluntary compliance with political decisions is a fundamental democratic challenge. Fair treatment by public officials plays a key role in theoretical and empirical studies on citizens’ compliance and cooperation. Yet it is unclear whether citizens within different societies react to (un)fair treatment in the same way. Using multilevel structural equation modelling and multilevel regression analysis on the European Social Survey 2010–2 (N = 52,458), this article shows that perceptions of fair treatment by police officers are associated with higher levels of trust in political institutions and in turn stronger compliant and cooperative attitudes of citizens in 27 countries. Yet the link between perceptions of unfair treatment and institutional trust is stronger in countries in which fair behaviour is more prevalent. While fair treatment is often considered to be a universal norm affecting citizens in a uniform way, this article sheds light on important cross-national variations.