ZY5000/15/32掩护式液压支架的优化设计

当支架工作一定时间后出井维护时,需要将前梁与顶梁之间的销轴拿掉后改为运输销轴连接,由于井底空间、设备有限,操作极为不便;另外,由于前梁千斤顶是靠销轴受力,因为支架工作时间比较长且井下环境恶劣,导致销轴出现变形、生锈等现象,以致销轴不易拆卸。     

基于磁记忆检测技术的游乐设施检测方法研究

在大型游乐设施中,销轴类部件以及焊缝作为核心金属连接件,承载较大载荷,起到关键的连接作用,直接涉及到人身和设备安全。在每年的定期检验过程中,对所规定的游乐设施重要轴、销轴的要求是进行不低于20%的无损探伤,而常规的无损检测方法只能检测出已然存在的宏观缺陷。本文讨论了常规无损检测技术在游乐设施中的应用,提出了磁记忆检测技术可以对游乐设施金属部件缺陷起到早期预报作用,磁记忆信号梯度值K可以表征45钢缺陷的部位。在一定程度上,弥补了常规无损检测方法无法探伤轴的内部应力集中区等缺陷早期形态的不足。     

销孔直径、销孔间隙与孔壁承压容许应力取值研究

销连接是现代钢结构连接常用形式,现实条件下销轴和销孔之间都会有间隙。在弹塑性阶段,通过数值分析以塑性区面积为"桥梁"研究了销孔间隙对耳板孔壁承压建议容许应力的影响。     

大吨位起重机臂销轴内螺纹加工方法探究

1000吨级、800吨、500吨等大吨位臂销轴的加工是起重机伸臂部分的关键技术之一。臂销轴起到伸臂的自锁、定位,伸缩及起重时的载重作用,所以其加工必须严格的符合图纸要求,它直接关系到整车的使用性能和安全性,是产品安全、质量控制等重点关注的内容。由于该部件在机械加工的过程中出现了"轴向窜动"的现象,故设计出一套装夹工装来解决此问题。     

节气门端面车夹具

１概述如图１所示节气门为我厂生产的化油器上的一个关键零件，材料为铜板，其厚度公差要求控制在±０．０２mm范围内，国产板料很难达到上述要求，所以用１．５mm厚的板料冲制的节气门在装入节气门轴槽时十分困难，由于工件材料不能用平面磨床磨削加工达到尺寸要求，因此设计了一副车夹具在车床上加工。２结构（如图２）夹具由两部分组成：一部分由夹具体１和两个用于支承零件的定位销２组成，该部分装在车床主１．５±０．０２２－Φ４７５°Φ３０１６图２１夹具体２定位销３工件４轴５压紧柱６支承座７弹簧８尾锥轴上。另一部分由尾锥８…     

煤矿机械中铰销润滑结构与方法探究

文章首先列举了几种典型的煤矿机械中的铰销润滑结构,通过对这些结构的对比和分析,指出虽然这些结构经常被人们使用,但是它们仍然是优点与问题并存的。因此,文章提出了一种新型的铰销润滑结构,该结构能更适用于煤矿机械中铰接轴的润滑,通过对这种新型铰销润滑结构的介绍以及其与传统铰销润滑结构的对比,展现了新型铰销润滑结构的优势以及发展前景。     

长圆孔销轴的孔壁承载力计算

应用规范公式与有限元分析结果进行对比,并提出了一种新型的长圆孔专用销轴     

移动式垃圾转运站箱体有限元分析与优化设计

利用ANSYS软件对移动式垃圾转运站箱体结构建立了参数化几何模型和有限元分析模型,采用接触副合理解决了推头、垃圾、箱体间的接触和轴销连接问题.在此基础上进行了压缩进程、上车进程、满载颠簸、刹车行驶、卸料顶起和翻斗作业最大反力等11种危险工况下的约束、加载和结构有限元分析计算,得出各工况下结构的应力分布和最大应力.采用ANSYS与导重法相结合的结构优化方法对移动式垃圾转运站箱体结构进行了优化设计,在满足结构强度要求的前提下,使箱体结构的总重量减少了20.2％.     

30 t轴重载铁路弹性道砟垫的技术应用效果研究

文章通过对工程实例的分析,明确了30 t轴重载铁路道砟垫的技术应用效果。结合工程实例项目的分析,明确30 t轴重载铁路道砟垫的技术应用需要满足国家标准要求,并且要在过程中,充分考虑后续投入使用的效果,保证维护及安全运行的要求。利用工程试验结果,验证了道砟垫的技术应用在刚度、强度、外观等方面,均能够较好地满足施工规范要求。因此,可以确定道砟垫的技术可以广泛应用于重载铁路施工。     

浅谈卧式电机大轴偏移处理的处理方法

为了有效解决由于抽水站电机大轴偏移问题,大北沟抽水站针对电机与泵轴弹性柱销式联轴器的特点,采用加垫片的办法解决了电机大轴偏移问题,方法简单易行,费省效宏。     

Development in Information and Communications Technology (ICT) Statistics at the Australian Bureau of Statistics

This paper outlines the ICT statistical developments that the ABS has undertaken over recent years. These developments have been on both the supply side (ICT industry) and the demand side (use of IT by sector). The content of ABS ICT surveys has changed significantly over the last few years and are expected to develop further in line with industry changes and emerging policy needs.
Recent developments in household collections have been the inclusion of IT use questions in the 2001 Census of Population and Housing and in various ABS social surveys such as Children's Participation in Culture and Leisure Activities. Annual business IT use surveys are now conducted and include topics such as Internet commerce and IT security. Biennial ICT industry surveys are conducted to provide data on ICT production, imports and exports, ICT industry employment, performance and structure information. An Internet activity survey is run every six months and provides regional Internet access details and infrastructure details on Internet service providers.
A major development for 2002–03 will be the compilation of an ICT satellite account. ABS intends to produce an ICT Information Development Plan to guide its future statistical development work in the ICT field.     

Value at Risk in the Suburbs: Eminent Domain and the Geographical Politics of the US Foreclosure Crisis

Several US counties and local governments have recently considered a novel solution to the foreclosure crisis. They plan to use eminent domain to compel the owners of mortgage debt—and specifically of private‐label mortgage‐backed securities—to sell the debt to the government at a price reflecting the loan's market value. The government would then restructure the debt and resell it to new investors. The plans are striking because—in contrast to both development‐driven eminent domain and the federal subprime bank bailout—they would force investors to assume asset devaluation and increased long‐term risk. Notably, the plans have emerged as an instance of financialization‐focused politics in suburbs and suburban cities of color, specifically majority‐black and ‐Latino/a suburbs. Local support for the plans, we argue, is rooted in the long‐term disinvestment of these ‘suburbs of exception', which became targets of subprime lending and eventually sites where the ‘financial exception' has been localized. But these demographic shifts, fragmentation and fiscal pressures have at the same time created a suburban political terrain in which the plans have gained their strongest political support.     

Towards a Theory of Serendipity: A Systematic Review and Conceptualization

Serendipity – the notion of making surprising and valuable discoveries – plays a major role in the success of individuals and organizations alike. Previous research has established the importance of serendipity and identified important individual- and organizational-level antecedents. However, the literature has been dispersed and the boundaries of the concept have been blurry, leading to a lack of conceptual clarity and structure, and thus limiting validity and managerial actionability. Based on a systematic literature review, I synthesize existing management-related research on serendipity and explicate the emergence and composition of serendipity in the organizational context. I first identify three necessary conditions that differentiate serendipity from related concepts such as luck or targeted innovation: agency, surprise, and value. Then, I draw from the literature on sensemaking, event-based theorizing, and quantum-based approaches to management to conceptualize the process of cultivating serendipity in the organizational context as a process of enabling potentiality and materialization, and develop a multi-level theory of (cultivating) serendipity. This conceptualization contributes to our collective understanding of how, why, and when (i.e., under what conditions) organizations can leverage the value in the unexpected, which opens up fruitful avenues for further research.     

Accountability of NGOs in Bangladesh A critical overview

NGOs in Bangladesh have been recognized as effective change agents in the socio-economic arena throughout the world. Their contributions in micro credit, non-formal education and primary health care are widely known. NGOs play a significant role in society. NGO accountability, as a result, has become a critical issue. NGO accountability in Bangladesh has been examined here in relation to patrons, clients and themselves. Of the three relationships only accountability to patrons is in a near satisfactory state. Accountability to clients is handicapped by lack of opportunities of beneficiaries to participate meaningfully in NGO policy making. Accountability to themselves is adversely affected due to the adherence to a strictly hierarchical system and the influence of founding and charismatic NGO leaders.     

Towards an Asian model of human resource management? A comparative analysis of China,Japan and South Korea

There has been much discussion regarding the possible decline and weakening of national systems of human resource management (HRM). Yet, culture and institutions are often cited as the major stumbling blocks to this outcome. Such constraints may dissipate in the analysis, particularly if ‘regional clusters’ are considered where geographic and cultural closeness and ‘openness’ to similar economic pressures exist. In such cases, it might be postulated that convergence in HRM will occur. We argue that China, Japan and South Korea represent such a cluster. This article examines these countries, to see if a degree of convergence is taking place and if it is towards an identifiable ‘Asian’ model of HRM. A model of change is presented that distinguishes between levels of occurrence and acceptance. Details of the development and practice of HRM in each country are then set out. The article ends with a discussion and implications section and a brief conclusion.     

Ansätze und Ergebnisse anglo-amerikanischer M&A-Forschung

Based on a review of established U.S. management journals (1995–2003), six schools of thought are identified within the Anglo-American M&;A research: “Capital Market”, “Principal/Agent”, “Industrial Organization”, “Organizational Behavior”, “Human Resources” and “Strategic Management”. The literature review shows that the definition of M&;A success, the methods applied, and insights from empirical research differ according to the respective school of thought. Empirical studies focus on the resource combinations of merger partners, the specific circumstances of merger negotiations, and on integration management as antecedents of merger performance. Unfortunately, empirical findings have not yet provided reliable explanations for M&;A success. Based on the current state of Anglo-American M&;A research, the authors discuss implications for business practice, identify research gaps, and propose areas for future research.     

Introduction of New Technology with a Sound Transition of the Input-Output Structure

We examine the general equilibrium repercussions associated with the introduction of new technologies, using the generalized Leontief system that allows technological substitutions. We show that an untested introduction of cost-increasing technologies in any industry may result in creating a non-productive technological structure that does not satisfy the Hawkins-Simon condition, following the autonomous dynamic adjustment process with structural transitions in the economic system. Therefore, we propose a practicable control scheme of introducing cost-increasing technologies that strictly avoids the creation of non-productive structures in all periods of structural transition, using the available information on the ex ante technological structure.     

The Creation of the Office for National Statistics

A new Office for National Statistics was created in the United Kingdom in 1996 following a series of developments designed to strengthen the relevance and integrity of statistics. This paper describes these fundamental changes and sets out a blueprint for future progress. It also sets current developments in the United Kingdom in an historical and international context.     

What helps? Women engineers' accounts of staying on

We have considerable understanding of the obstacles that women engineers encounter and the reasons that they leave the field, but we know less about what enables them to remain. Adopting an interpretivist approach, this article examines how a group of British women engineers in two FTSE 100 companies account for “staying on” in their male‐dominated work settings. We delineate four specific forms of help that facilitate women's retention in the field. We argue that exposure to help leads to women developing a habitus that enables them to continue working in engineering. To conclude, we draw on our findings to outline HR practices that will facilitate supportive relationships in the workplace and pave the way towards developing more positive organisational climates.     

论现代物流企业的发展观

物流业经过诸多年的发展目前已经成为最热门的行业之一,物流企业的注册数量也与日俱增,达到前所未有的规模。毋庸置疑,任何企业都希望自己迅速做强做大,并成为真正现代物流企业的典型代表,要实现这一目标一个首要问题就是要解决现代物流企业的发展观问题。