关于压杆构造长细比控制的一点看法

同直径空心管材,壁厚越大,杆件回转半径越小,即同等约束条件下,长细比比值比壁厚小的杆件大,作为压杆长细比构造条件控制情况,会得到同等条件下壁厚大的管材不如壁厚小的杆件的结论,本文从实际轴心受压构件受压稳定性角度论述单用构造长细比选压杆构件截面的方法不妥。     

大容量涤纶长丝生产线技术发展综述

近年来,化纤行业的迅速发展促进了我国涤纶长丝生产技术的不断成熟,同时更多的涤纶长丝生产线也不断建成并投入使用,为我国涤纶长丝生产提供了更为强健的基础。但在涤纶长丝生产线投入使生产的初期,很多生产线生产的产品都存在毛丝多、断头率高以及僵丝、染色率差等问题,产品质量还有待进一步提高。本文针对影响大容量涤纶长丝生产线生产质量的主要因素进宪了分析,并综述了如何解决这些问题所采取的策略,为大容量涤纶长丝生产线的实践应用提供借鉴基础。     

数控车床变速车削梯形螺纹的应用技巧

文章论述了一种可以解决变速车削梯形螺纹时产生乱牙问题的简单实用的数控车削加工方法,即车削螺纹时可以先用较高转速粗加工车削,再用低速来精车及修光,从而达到既提高了生产效率,又能很好地保证了螺纹的尺寸精度和表面粗糙度有效的数控车削梯形螺纹方法。     

基于虚拟加工的数控车削优化探析

随着车削技术的不断进步,人们对于数控车削优化的关注度也逐渐增强。为了做好车削加工过程优化,提升加工效率,就需要了解数控车削加工工艺,文章基于虚拟加工的数控车削优化的实证分析,希望可以对虚拟加工技术和数控车削优化有一个全面的认识与了解,从而为后续的研究奠定基础。     

怎样鉴别丝绸化纤织物

市场上的棉布、的确良、化纤织物（中长、长丝）如何鉴别？这就需要用感观的方法和试验的方法来判断鉴别是什么纤维。首先用眼观察布面的光泽和色泽,用手摸布面的感觉而作出大致的判断。如的确良光泽明亮、色泽淡雅,手感滑、挺、爽。富纤布和人棉布色泽鲜艳、光泽柔和,手感滑软、光洁。从织品中抽出几根纤维,如果是长丝可用舌关将丝条润湿,若在润湿处拉断,那就是粘胶长丝;不一定在润湿处拉断,则是蚕丝。纤维在干湿状态下强度都很好,则是锦纶、涤纶、丙纶等合纤。如果是短纤维,如果长短不一,那可能是羊毛、棉花等天然纤维。细的大…     

浅谈教学训练中车削螺纹时产生废品的常见原因及解决方法

在金工实训车工教学过程中,车削螺纹是车削加工中较为复杂的加工内容之一.在车削螺纹训练时产生废品的原因比较复杂,既有车床的原因,也有螺纹车刀、操作员等原因,造成车削螺纹时的常见原因有:牙型不准、乱扣、螺距(或导程)不正确、扎刀和项弯工件、螺纹表面不光洁等,在思考解决产生废品的原因时要视情况分析,通过各种检测和诊断手段,找出具体的影响因素,针对产生废品的原因采取相应的解决方法.     

铰链四杆机构的微进给应用研究

本文紧密结合工程实际应用,以超精密车削加工中的微进给系统为研究对象,以在收集了大量资料的基础上,探讨铰链四杆机构在微进给系统中的应用设计措施,结果计算其具备多条轨迹的综合,且具有较高的精度,值得推广应用。     

分层法车削超大梯形螺纹

石油化工企业有许多大型设备,超大梯形螺纹在设备中经常能用到,超大梯形螺纹车削是车工常见的技术难题,由于车削加工难度较大,对操作者的技能要求较高,因而操作起来较为困难.为了解决此难题,介绍了操作简单、易理解和易掌握的“分层”车削方法.     

梯形丝杆加工技巧

正细长轴加工是车削加工中的难题,而要在轴上车出梯形螺纹,其难度就更大了。因为细长轴本身刚性就差,在车削过程中,受切削力、装夹力、自身应力、振动和切削热等因素的影响,容易造成车削尺寸精度超差、加工表面粗糙度值、报废等缺陷。笔者探讨出加工小螺距丝杠加工的技巧。     

一体式压杆稳定性分析方法

一体式管状压杆承载能力高且重量较轻,因此被越来越多地应用于运输类飞机发动机安装中。但受限于结构形式,一体式压杆两端通常为变截面形式。针对一体式压杆结构特点,使用工程方法和有限元分析方法对几种不同参数的压杆稳定性进行分析,并与试验结果进行了对比验证。结果表明,工程方法和有限元分析方法计算误差随压杆长细比增大而增大。但有限元分析方法得到的结果优于工程方法。该研究为一体式管状压杆的设计提供了分析方法和试验支持。     

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.     

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。     

浅谈大体积混凝土裂缝的控制

大体积混凝土的裂缝问题是实际工程中长期困扰工程技术人员的问题,其控制技术的研究是混凝土结构研究的热点问题,具有重大的学术价值和潜伏的工程背景。     

Supply Chain Strategies in the UK Fashion Industry—The Rhetoric of Partnership and Realities of Power

This paper focuses on the fashion industry, one characterised by issues such as dramatic shifts in the scale and power of major retail buyers in the market, the advent of retailer own brands, and the nature of sourcing and supply chain decisions, issues that are increasingly global in nature. The aim of this research is to explore the nature of relationships between UK high street multiple fashion retailers and their contracted suppliers, many of whom are entrepreneurial firms by most definitions of the term. Four core themes emerge from the literature and provide a framework for the research, namely, power, process, partnership, and people. The research approach was qualitative, and conducted over a period of twelve months. The paper ends with an agenda for future research.