备用电源自动投入装置手跳闭锁功能的实现

介绍了微机型备用电源自动投入装置手跳闭锁功能的实现方式,对备用电源自动投入装置按照手跳闭锁功能实现方法的不同进行了分类,对保护装置按有无STJ和KKJ进行了分类,分析了备用电源自动投入装置与各种保护之间的配合方法。     

廖坊水电站机组流道排水处理方法分析

廖坊水电站机组甩完负荷后需要进行流道检查.进水口检修门与尾水事故门止水效果不好,导致流道中的水排不干,无法进行流道检查.就此问题进行分析,提出处理方案.按处理方案重新操作后,解决了闸门止水问题.     

北京市工业用水节水分析及工业产业结构调整对节水的贡献

在分析20世纪90年代北京市工业及主要耗水行业节水特点的基础上,重点研究了产业结构调整对节水的作用,并以定量的形式计算出在不同时间段工业产业结构调整对节水的贡献率。1990—1994年间工业产业结构调整对节水的贡献率为29.5%,1994年以后比重逐渐上升,1998—2000年间比重已达到46.1%,表明1990—2000年间产业结构调整对北京市工业节水的贡献率呈上升趋势。     

高温炉管断裂的两种机制

通过对过热炉管受热冲击影响的事件考察，指出了在高温炉管的断裂中存在着超温引起过早的蠕变断裂，通常有明显的变形和热冲击导致快速的脆性断裂两种不同的机制。在失效成因的分析中，讨论了Manson—Haferd参量外推技术、热应力沿壁厚的分布和热冲击产生应力峰值问题，给出了热冲击的安全曲线。     

Precursor system of liquid crystalline phase containing propolis microparticles for the treatment of periodontal disease: development and characterization

Precursor systems of liquid crystalline phase were prepared using the surfactant PPG-5-Ceteth-20, isopropyl myristate, and water; gelatin microparticles containing propolis were then added into these systems. Homogeneity of dispersion, the in-system microparticle morphology, and sedimentation behavior of each formulation were evaluated. The rheological and mechanical properties (hardness, compressibility, and adhesiveness), the work of syringing, and the propolis release profile were also evaluated. All the formulations exhibited pseudoplastic flow and thixotropy, and they displayed storage modulus, loss modulus, dynamic viscosity, and loss tangent that depended on temperature, frequency, and composition. Mechanical properties varied significantly among the formulations being affected by changes in the composition and temperature. Raising the concentration of surfactant and adding propolis microparticles significantly decreased the work of syringing. The drug release was non-Fickian (anomalous) and there was no significant difference between the tested systems in the times required for 10%, 30%, and 50% release of the initial drug loading.     

大型深基坑支撑爆破拆除中的技术措施

分析了深基坑支撑拆除工程爆破中的技术难点,提出了对重点对象的保护措施,研究了支撑爆破振动的有效控制和延期网路的可靠连接,对装药量、爆破防护和施工组织进行了讨论,工程实践证明采用介绍的设计方案可以得到良好的爆破效果.     

Robust event correlation scheme for fault identification in communication networks

The complexity of communication networks and the amount of information transferred in these networks have made the management of such networks increasingly difficult. Since faults are inevitable, quick detection, identification, and recovery are crucial to make the systems more robust and their operation more reliable. This paper proposes a novel event correlation scheme for fault identification in communication networks. This scheme is based on the algebraic operations of sets. The causality graph model is used to describe the cause‐and‐effect relationships between network events. For each disorder, and each manifestation, a unique prime number is assigned. The use of the greatest common devisor (GCD) makes the correlation process simple and fast. A simulation model is developed to verify the effectiveness and efficiency of the proposed scheme. From simulation results, we notice that this scheme not only identifies multiple disorders at one time but also is insensitive to noise. The time complexity of the correlation process is close to a function of n, where n is the number of observed manifestations, with order O(n²); therefore, the on‐line fault identification is easy to achieve. Copyright © 1999 John Wiley & Sons, Ltd.     

Disciplining Communication Study at the University of Illinois at Chicago, 1973–2007

This article combines a theoretical exploration of the concept of disciplinization with a practical report on the departmental history of the Communication program at the University of Illinois at Chicago. The discussion of disciplinization is supported by theories of disciplinarity taken from Michel Foucault and Max Weber among others and the departmental history is formed from archival research and in-depth interviews with faculty. The result is a model for writing departmental history that contextualizes the concept of disciplinization within an historical account of the decisions made during the course of a program's development.     

Sensitivity of expected exceedance rate of SDOF-system response to statistical uncertainties of loading and system parameters

The effects of the statistical uncertainties of the loading and system parameters on the mean exceedance rate of a particular threshold are investigated for a linear SDOF-system with viscous damping. For this purpose the structural loading is described by the well-known stationary Kanai-Tajimi-earthquake model. The analysis is simplified by utilizing an approximate solution for the threshold-crossing rate, for which the error with respect to the exact solution is shown to be small. Each of the parameters involved in the expression for the mean exceedance rate of the stationary response of the structure is considered a random variable. The respective effects of the statistical uncertainties of the parameters on the threshold-crossing rate, as expressed by the first- and second moments, are shown explicitely in the numerical examples.