Determining spacing by radiant heat limits

A method for calculating the “safe” separation distance between pressurized LPG storage tanks and flammable liquid storage tank dikes is presented. The safe separation distance is defined as the minimum distance at which the radiant heat from a dike fire is insufficient to cause catastrophic tank failure, even if no cooling water is applied to the LPG tank.     

Hazard analysis and safety considerations in refrigerated ammonia storage tanks

A systematic approach to find out the probability of Ammonia tank failure was adopted and a consequence analysis in case of accidental Ammonia release from refrigerated ammonia storage tanks was made. The study revealed that construction of a concrete bund wall around the tanks is not justified. Instead, it would be adequate to upgrade the safety in the common dyke around the tanks by adopting additional conventional methods.     

立式金属罐腐蚀原因分析

立式金属储罐罐顶、内部附件及罐底边缘板腐蚀一直是影响立式金属罐使用寿命的一个重要因素,针对安塞油田立式金属罐腐蚀现状,分析了防腐工艺及内部附件在设计上存在的弊端,提出新的防腐及施工工艺。     

出口企业反倾销中非市场经济地位问题应对策略

2009年,欧美等国对我国进行多起反倾销、反补贴调查,严重影响我国出口企业经济恢复和发展。非市场经济地位问题是影响反倾销诉讼成败的关键因素之一。本方试阐述我国被认定为非市场经济国家法律依据;挖掘反倾销中非市场经济地位理论缺欠;提出解决非市场经济地位问题措施和建议。     

Men versus women in industrial sales: A performance gap

Sales managers have typically directed an all-male sales force. Today, they are recruiting women for positions in industrial sales. Whereas such managers may have a number of questions about women, probably the single most important question is how men and women compare in job performance. Although trade publications report that women have done quite well in sales [1], the question should not be considered resolved. Trade reports are extremely useful but are not based on systematic evidence. Another difficulty with trade reports is the failure to test for spurious relationships, that is, apparent relationships due to variables correlated with both sex and performance. In particular, variables that may be related to both sex and job performance should be examined to see whether job performance differences are actually due to the sex of the person or whether such relationships are spurious.     

Firm Survival in the Netherlands

The purpose of this paper is to examine whether the dynamics of industrial organization differ in the Netherlands from what has emerged as a Stylized Fact in other countries. Because the Netherlands has pursued a unique set of institutions and policies comprising what has become known as the Polder Model, the factors leading to firm failure may systematically differ from those in other countries. We address this question using a longitudinal database from Statistics Netherlands (CBS) that identifies over two thousand firms in manufacturing and then tracks their performance over time.     

储罐设计标准关键技术问题探讨

针对国内外储罐事故的经验教训,系统梳理了国内外储罐设计标准。为了提高国内储罐标准的先进性,分别从储罐附件设计、储罐消防设计和储罐安全设计3个方面,深入研究了国内外标准差异。国外储罐标准技术先进性包括储罐安全距离、浮顶储罐浮盘状态监视、储罐泄漏检测和防渗设计等方面。最后借鉴国外标准先进理念,就完善国内储罐设计标准提出了建议。     

间歇式自动冲洗水箱的原理和应用

现有公用卫生间的冲洗水箱种类虽多 ,但都存在共同的缺陷 ,结构复杂 ,易损坏 ,使用成本高 ,一旦损坏 ,随即影响到公用卫生间的环境卫生。为此设计出一种利用虹吸原理的间歇式自动冲洗水箱 ,不需人为控制 ,不需动力 ,能达到自动冲洗便坑的效果。整个结构中没有活动零件 ,也就没有易损件 ,最大的特点是不易损坏 ,从某种意义上讲 ,可以说永不损坏。安装方法、使用效果和其他形式一样 ,只有几个零件组成 ,结构比其他类型的自动冲洗水箱简单 ,应用虹吸原理可靠 ,可全为塑料制品 ,生产成本低于同类产品 ,宜于推广应用     

The Incidence of Property Taxes on Single-Family Housing*

The incidence of local property taxes, specifically the degree of capitalizing of property tax differentials in market prices, remains an unresolved question. The studies by Oates (1969) and McMillan and Carlson (1977) , which come to contradictory conclusions typify the diversity of opinion on the question. Many of the previous studies suffer from research design problems including, the use of census data for market values and property tax levels on real property; failure to control for differences in public services quality among the cities samples; and use of assessed value as a proxy for market price. A theoretical model in developed to explain the capitalization effect of property tax differentials within an urban area. Because the model is exactly identified, a single reduced from equation relating market value to a set of physical characteristics of the property and the level of property taxes can be estimated using ordinary least-squares techniques. The function is estimated using data drawn from 107 residential property sales made during 1976. Estimated parameters for the other equations then are determined indirectly. Actual market price and property tax data for each parcel ware used. It is found that property tax differentials on otherwise comparable properties are associated with significant market value differentials. Because the assessed value ranges from 7 to 20 percent of market value, the property tax procedure in the area studied appears to have randomly generated large capital gains for some and capital losses for others. Because of the limited data base, the statistical results are only indicative; the model, howevfer, should have wide applicability in a variety of questions concerning the incidence of property taxes.     

球罐地震反应分析及其子结构拟动力试验方法

为了研究流固耦合作用对球罐地震反应的影响,利用ABAQUS软件建立1 000m3球罐有限元模型。采用子空间法对球罐进行了模态分析,并与规范算法进行对比,同时采用耦合拉格朗日欧拉算法,对考虑液固耦合作用的球罐进行地震反应分析。分析结果表明:考虑液固耦合作用使球形储罐的顶点位移、竖向支反力、支柱底部剪力以及拉杆应力等方面衰减得更快,并且在数值上也比附加质量法所模拟的结果小很多。在此基础上,介绍了子结构拟动力试验方法,提出将子结构拟动力试验方法应用于球形储罐的抗震性能分析,阐述了球形储罐子结构拟动力试验的步骤,为球形储罐抗震研究提供一种新的试验研究思路。     

原油储罐油水计量在线监测系统

论述了原油储罐油水计量在线监测系统的基本原理及其确定圆柱形油罐内油水量的方法，成功解决了油水过渡带这一困扰油罐计量的难题。该系统特别适合储存非均质的、两种不同性质液体的圆柱形储罐。     

The Productivity-Enhancing Impacts of the Minimum Wage: Lessons from Denmark and New Zealand

This article adds an international comparative perspective to the reflection on 100 years of minimum wage legislation in Britain by exploring the impact of minimum wage regulations and institutions in Denmark and New Zealand. In particular, it looks at the question of whether minimum wages can raise productivity through the 'shock effect'. It argues that while they will play a role, a supportive institutional framework is more important in providing coordinated solutions to issues of market failure, such as inadequate levels of training. The article suggests that sectoral bargaining institutions in low-paid sectors may have the potential to facilitate such coordination and enable the high-productivity model to emerge.     

Experiments on the thermo-hydraulic response of pressure liquefied gases in externally heated tanks with pressure relief

An experimental program is described and experimental results presented for the response of an externally heated horizontal cylindrical tank protected by a PRV and partially filled with a pressure liquefied gas. Measurements of tank pressure, temperatures, mass discharge and void development, along with photography of internal fluid behavior are used to demonstrate the complex thermo-hydraulic behavior as a function of heating and valve position. The results are used to compare some of these parameters with analyses of stratification and void development.     

Complementary assets as pipes and prisms: Innovation incentives and trajectory choices

The issue of the failure of incumbent firms in the face of radical technical change has been a central question in the technology strategy domain for some time. We add to prior contributions by highlighting the role a firm's existing set of complementary assets have in influencing its investment in alternative technological trajectories. We develop an analytical model that considers firm heterogeneity with respect to both technological trajectories and complementary assets. Complementary assets play a dual role in incumbents' investment behavior toward radical technological change: they are not only resources (pipes) that can buffer firms from technology change, but also prisms through which firms view those changes, influencing both the magnitude of resources that should be invested and the trajectory to which these resources should be directed. Copyright © 2013 John Wiley & Sons, Ltd.     

Financial Participation: Does the Risk Transfer Story Hold in France?

Several articles report a positive effect of financial participation (profit sharing (PS) and employee share ownership) on firms' economic performance. This increase can be obtained in two main ways: by increasing the effort (extrinsic, intrinsic or commitment) of workers, directly or indirectly through worker selection; or by transferring more risk to the workers. The question is, of course, not neutral. Indeed, if the risk transfer story is true then it means that the increase of economic performance is obtained at the expense of workers, who take on the burden of more risks. The question is especially important in France where financial participation is associated with tax exemption for firms and where it is forbidden by law to substitute base wage and PS. The purpose of our article is to use an employer–employee dataset to answer the question of whether financial participation schemes are mainly designed as a risk transfer (from firms to workers) device.     

甲醇罐区消防及喷淋冷却水系统的设计优化

为加强消防系统的安全性和实用性,实现甲醇罐区喷淋冷却水的节水回用,依据相关规范,从形式选择、设计计算、系统布置和操作控制等方面阐述了消防及冷却系统设计的优化方法。根据点火源模型的计算结果,提出甲醇罐区泡沫消防管道设计宜采取分散布置,替代原来集中布置的敷设形式,优化后夏季喷淋冷却系统的水回用率达到了98.25%。通过优化,降低了储罐事故状态下热辐射对相邻泡沫管道的影响程度,减少了消防车械的拥堵状况,提高了消防精度。此外,循环夏季喷淋冷却系统还有效减少了企业污水的排放量,人工操作量小,实现了较为智能的冷却水回用功能。     

一种矿井井下水仓自动排水系统

本文介绍了一种用于矿井井下的水仓自动排水系统,并提出了一种新方法。通过区别小电机是空载还是满载来确定水仓的状态。从而控制被简化。     

石油及液体石油产品静态计量技术

介绍了石油静态计量基础知识,包括物理特性、大罐的标定、温度、液位、含水的测量方法,最后给出了标准计算顺序。     

大型浮顶储罐非平面倾斜纠偏实践

介绍了2万m^3浮顶油罐基础发生非平面倾斜，导致密封装置漏油问题的经过，提出了简易可行的处理方案．并就有关规范和标准问题进行了探讨。     

An ammonia storage tank study

An in-depth hazards review and subsequent field work on a 20-year-old ammonia tank are discussed, as well as a new method used to change tank valves. Included are a risk assessment of critical piping and a fracture mechanic study of the tank.