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1.
以往超前、端头支护所使用的支护设备为单体柱配合金属梁支护顶板,不仅支护强度小,支柱易出现退山柱,特别是顶板来压明显时顶板下沉量明显加大,对顶板支护十分不利,而且人工搬运铁活出伤工事故的概率较大。端头、超前支架的应用使这些问题都迎刃而解,保证了生产安全高效地进行。  相似文献   

2.
以往超前、端头支护所使用的支护设备为单体柱配合金属梁支护顶板,不仅支护强度小,支柱易出现退山柱,特别是顶板来压明显时顶板下沉量明显加大,对顶板支护十分不利,而且人工搬运铁活出伤工事故的概率较大。端头、超前支架的应用使这些问题都迎刃而解,保证了生产安全高效地进行。  相似文献   

3.
本文通过对炮放工作面端头顺山棚防倒防滑装置研制与应用,解决了炮放工作面端头处安全系数小的问题并增强强了端头顺山棚的支护强度,从而提高了炮放工作面的生产效率。  相似文献   

4.
在综放工作面采煤过程中,端头支护始终是顶板支护环节亟待攻克的一项技术难题。传统液压支护形式既费工又费时,而且安全性能始终达不到预期。为实现端头支护,枣矿集团鲁南装备公司将放顶煤端头支护技术纳入科研攻关课题,通过技术人员努力成功研制了zt10000-25/50型端头卸载支架,于2013年8月初在田陈煤矿3下7110综放工作面进行安装试用并取得成功。  相似文献   

5.
通过对古山煤矿地质条件的分析,利用数值模拟法和估算法确定了支架的主要技术参数和结构特点;并针对古山矿工作面大倾角的特点,选择了相应的布置方式,有效改善了支架受力状态,使长期难以解决的端头复杂支护问题得到简化。  相似文献   

6.
锚杆支护作为一种有效的采矿巷道支护方式,由于对围岩强度的强化作用,可显著提高围岩的稳定性,加之成巷速度快、劳动强度低、提高巷道断面利用率、简化回采面的端头维护工艺,明显改善作业环境和安全生产条件,成为矿井巷道的主要支护形式,得到了大力推广应用。文章对锚杆支护的优点和具体施工作相关探讨,以供相关人员参考。  相似文献   

7.
刘峰  李彦才  林映红 《科技与企业》2014,(11):188-188,190
(一)概况 单体液压支柱是利用液体压力产生工作阻力并实现升柱和卸载的单根可缩性支柱。单体液压支柱是一种新环保型的、恒阻式支护装备,既可与金属铰接顶梁配套用于一般机械化采煤或炮采工作面支护项板用,以及综采工作面支护端头,也可单独做点柱或其它临时性支护用。  相似文献   

8.
某工程的基坑支护锚索施工中采用锚索末端高压喷射扩孔,形成扩大端头段的锚索体系,在扩大段端头的同时还具备支承作用,极大地改善了锚索的受荷性能,能显著提高单根锚索的抗拔力,形成一种非常有效的锚索抗拉拔体系。  相似文献   

9.
张修身 《价值工程》2013,(21):103-106
地铁地下车站一般为狭长形状,其标准段变形以横截面上的平面变形为主,因此通常采用二维平面模型进行分析,但对盾构端头井段等部位,由于其受力具有典型的空间特性,荷载-结构平面框架计算方法无论在精度或可靠度上都达不到设计要求,因此,需建立空间整体模型对其进行受力分析。本文介绍了端头井计算模型和计算中存在的问题,探讨了端头井的分析计算方法,并通过实例详细介绍了端头井空间三维计算模型的建立、荷载的组合、荷载图式、约束条件等,运用软件对模型进行了计算,对计算结果进行了分析,得出的结论对类似工程的设计有一定的参考价值。  相似文献   

10.
在对煤矿进行作业的过程中,为了提高经济效益,本文通过对综采大倾角采煤方法、回采工艺流程,以及端头及上下出口支护进行阐述,同时提出大倾角采煤的要点和生产的主要措施,进而为大倾角工作面开采提供参考依据。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
杨明 《价值工程》2012,31(7):16-17
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。  相似文献   

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