第二煤矿三水平掘进工作面供电系统的优化

结合第二煤矿井下掘进工作面供电系统的实际情况,为了使第二煤矿三水平三区段30#层掘进工作面供电系统合理、安全、可靠、经济运行,对掘进工作面的供电系统进行了优化改进,确保了三水平三区段30#层掘进工作面供电系统的稳定性、连续性和可靠性,保证了掘进面的安全生产。     

煤矿井下供电系统中漏电保护技术研究

文章针对煤矿供电系统中高压漏电保护的问题进行了分析,根据零序电压、电流的特征与高压漏电保护整定原则,对现有电流方向型高压漏电保护装置进行了性能分析,并分析了漏电保护计算整定方向型高压漏电保护装置进行了性能分析,并分析了漏电保护计算案,对实际工作有一定的指导意义。     

煤矿井下漏电的原因分析及预防措施

煤矿井下是一个特殊的环境,一旦发生漏电,带来的危害远比在地面上要严重.因此,分析漏电的危害和原因,并且做到预防为主,及时修正,是提高煤矿井下安全性的重要手段.本文在分析煤矿井下供电系统漏电危害及原因的基础上,进一步提出了预防漏电事故的有效措施,对提高井下供电系统的安全性,有一定的借鉴意义.     

煤矿井下供电系统漏电原因及处理措施研究

在对煤矿井下供电系统漏电原因进行简单归纳总结后,对煤矿井下供电系统漏电危害进行了阐述分析.最后,结合自我多年实际工作经验,对预防煤矿井下供电系统漏电故障的技术措施进行了详细分析研究.     

试论井下漏电的原因、危害及预防

煤矿生产以井下巷道作业为主,由于井下环境恶劣,供电系统及设备容易发生漏电、人身触电、短路、过负荷、电火灾、电雷管提前引爆等电气事故。该文根据煤矿生产的环境特点,结合现场实际,从自然因素和人为因素等入手,具体分析了煤矿井下供电系统漏电的原因以及对煤矿生产和人身安全带来的危害,并提出了预防井下漏电及人身触电的具体措施,具有一定借鉴意义。     

试论井下漏电的原因、危害及预防

煤矿生产以井下巷道作业为主,由于井下环境恶劣,供电系统及设备容易发生漏电、人身触电、短路、过负荷、电火灾、电雷管提前引爆等电气事故。该文根据煤矿生产的环境特点,结合现场实际,从自然因素和人为因素等入手,具体分析了煤矿井下供电系统漏电的原因以及对煤矿生产和人身安全带来的危害,并提出了预防井下漏电及人身触电的具体措施,具有一定借鉴意义。     

煤矿掘进工作面自动化技术研究

本文对当前煤矿生产现状做了分析研究,并对煤矿掘进工作面的自动化系统及其使用范围进行说明,对于煤矿掘进工作面的掘进技术一一进行探讨,以期能够对煤矿的生产发展起着一定的促进作用.     

试论井下漏电的原因、危害及预防

煤矿生产以井下巷道作业为主,由于井下环境恶劣,供电系统及设备容易发生漏电、人身触电、短路、过负荷、电火灾、电雷管提前引爆等电气事故.该文根据煤矿生产的环境特点,结合现场实际,从自然因素和人为因素等入手,具体分析了煤矿井下供电系统漏电的原因以及对煤矿生产和人身安全带来的危害,并提出了预防井下漏电及人身触电的具体措施,具有一定借鉴意义.     

煤矿井下漏电的危害与预防

煤矿井下供电电网发生漏电不仅会引起人身触电，更有可能导致瓦斯和煤尘爆炸，引发火灾等重大事故。井下漏电故障点在供电系统中显示不明确，故障排除困难，长期存在的漏电电流导致漏电处绝缘降低损坏，在恶化发展中造成短路等事故，威胁矿井安全。煤矿井下涉及的供电线路长、设备多，工作面随着采掘等不断延伸，各项检修及人员的维修范围等工作能力不能满足实际的检修维护，在保障安全生产的过程中，降低供电电网的漏电危害。     

关于煤矿井下低压漏电保护动作值的思考

漏电保护在安全生产中有看非常重要的作用。所谓漏电保护就是防止人身触电及漏电引起的事故发生。即通过检漏继电器对网络绝缘监测,当线路出现漏电故障,网络绝缘低于规定值时继电器动作．开关能自动有选择、快速的切除故障线路、记忆显示故障参数,切断故障电源,实现漏电闭锁保护。文章介绍煤矿井下低压供电系统漏电保护漏电动作电阻值的选定方法,分析所存在的一些问题,提出了一种新的计算方法,得出了不同的一组漏电闭锁动作电阻值。     

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.     

Incumplimiento del salario mínimo en Europa central y oriental

En este estudio se analiza el incumplimiento del salario mínimo durante el periodo 2003–2012 en diez países de Europa central y oriental con salario mínimo obligatorio nacional. A partir de los datos de EU‐SILC y la metodología propuesta por Bhorat, Kanbur y Mayet (2013), se cuantifica la incidencia y magnitud del incumplimiento. Se realizan análisis de regresión sobre determinantes individuales, laborales y macroeconómicos. Aunque la incidencia permanece relativamente baja, los trabajadores a los que se dirigen las políticas de salario mínimo parecen los más expuestos a su incumplimiento. Con el tiempo, una mayor incidencia se asocia a una razón más alta entre salario mínimo y salario medio.     

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.     

Cultural Economy Planning in Creative Cities: Discourse and Practice

While a growing body of research analyses the functional mechanisms of the cultural or creative economy, there has been little attention devoted to understanding how local governments translate this work into policy. Moreover, research in this vein focuses predominately on Richard Florida's creative class thesis rather than considering the wider body of work that may influence policy. This article seeks to develop a deeper understanding of how municipalities conceptualize and plan for the cultural economy through the lens of two cities held up as model ‘creative cities’ — Austin, Texas and Toronto, Ontario. The work pays particular attention to how the cities adopt and adapt leading theories, strategies and discourses of the cultural economy. While policy documents indicate that the cities embrace the creative city model, in practice agencies tend to adapt conventional economic development strategies for cultural economy activity and appropriate the language of the creative city for multiple purposes.     

Input/output ranges and performance: an examination of US machine tool producers

Despite the establishment of high-tech multinational enterprises (MNEs) in Ireland since the late 1950s, the country did not succeed in closing the technological gap with most of its EU counterparts. The weak National System of Innovation (NSI), and in particular low business and government R&D levels, combined with a lack of research and technology linkages between MNEs and indigenous firms, explain these poor results. However, the Shannon region in the West of the country presents some specific institutional characteristics that could theoretically make the region a strong technological enclave. The various actors in the region - i.e. the administrative, financial, political and research institutions, as well as the business organizations - have indeed infused a new type of economic development. After a brief review of the available concepts and models articulated around these actors and their interrelationships, the paper analyses whether the Shannon region, taken as an illustrative example, mirrors a specific economic and technological localized setting. The study is based on a survey of indigenous and foreign firms.     

Sixty years of discrimination and diversity research in human resource management: A review with suggestions for future research directions

This article reviews discrimination and diversity research published in Human Resource Management (HRM) over the past 60 years. While discrimination and diversity are very different constructs, it is often informative to study them together, because when people recognize each other's diversity, this can result in bias, stereotyping, and discrimination. We conducted bibliographic searches for terms related to discrimination and diversity as well as a manual search through every title and abstract published in HRM over the last 60 years to assess article relevance. The search resulted in 135 research articles with 136 unique studies (i.e., samples) which are reviewed in this article. Sex and race are the demographics that have been examined the most in HRM, while religion has been examined the least. Moreover, the number of studies examining lesbian, gay, bisexual, transgender, and queer (LGBTQ) employees in the workplace in HRM has grown quickly within the past 10 years, culminating in a recent meta‐analysis. Our review looks at some of the earliest research published, the most recent research published, and the overall trends we identified in the research over the years for both discrimination and diversity articles. We then make future research suggestions and recommendations to advance the study of discrimination and diversity in the coming years.     

Multinomial distributions applied to random sampling of particulate materials

When sampling a batch consisting of particulate material, the distribution of a sample estimator can be characterized using knowledge about the sample drawing process. With Bernoulli sampling, the number of particles in the sample is binomially distributed. Because this is rarely realized in practice, we propose a sampling design in which the possible samples have a nearly equal mass. Expected values and variances of the sample estimator are calculated. It is shown that the sample estimator becomes identical to the Horvitz–Thompson estimator in the case of a large batch-to-sample mass ratio and a large sample mass. Simulations and experiments were performed to test the theory. Simulations confirm that the round-off error due to the discrete nature of particles is negligible for large sample sizes. Sampling experiments were carried out with a mixture of PolyPropylene (PP) and PolyTetraFluorEthylene (PTFE) spheres suspended in a viscous medium. The measured and theoretical variations are in good agreement.     

The Early History of the Cumulants and the Gram-Charlier Series

The early history of the Gram-Charlier series is discussed from three points of view: (1) a generalization of Laplace's central limit theorem, (2) a least squares approximation to a continuous function by means of Chebyshev-Hermite polynomials, (3) a generalization of Gauss's normal distribution to a system of skew distributions. Thiele defined the cumulants in terms of the moments, first by a recursion formula and later by an expansion of the logarithm of the moment generating function. He devised a differential operator which adjusts any cumulant to a desired value. His little known 1899 paper in Danish on the properties of the cumulants is translated into English in the Appendix.