板坯连铸涡流检测钢水液位系统的应用

介绍了新一代RAM型涡流传感钢水液位控制仪在莱钢板坯连铸机上的应用及其效果。     

科技期刊编辑专业化和学者化是保证期刊学术质量的关键

一般科技期刊刊载的论文内容都具有很强的专业性,这就要求科技期刊编辑必须具有丰富的专业知识和较高的学术水平才能胜任编辑工作.从编辑过程的选题组稿、论文初审、选择审稿专家和编辑加工四个方面对此进行了阐述,指出了提高科技期刊编辑的相关专业知识和学术水平的措施.     

变压器和电抗器声级测量方法的对比分析

介绍了变压器、电抗器声级测量方法－－声压法和声强法，并对影响测量结果的各种因素进行了对比分析。     

《无线电频率划分规定》学习心得

主要介绍学习新的《无线电频率划分规定》的目的，《无线电频率划分规定》的特点，作了哪些重要修改和划分表的主要内容及如何贯彻执行《无线电频率划分规定》。     

鞍钢1780mm热轧生产线"三电"工程施工概述

概述了鞍钢1780mm生产线技术改造工程中供电、传动及自动控制系统的构成、安装及调试技术要点,以及技术经济效果评述,可供同类工程施工参考.     

A hybrid extended finite element/level set method for modeling phase transformations

A hybrid numerical method for modelling the evolution of sharp phase interfaces on fixed grids is presented. We focus attention on two‐dimensional solidification problems, where the temperature field evolves according to classical heat conduction in two subdomains separated by a moving freezing front. The enrichment strategies of the eXtended Finite Element Method (X‐FEM) are employed to represent the jump in the temperature gradient that governs the velocity of the phase boundary. A new approach with the X‐FEM is suggested for this class of problems whereby the partition of unity is constructed with C¹(Ω) polynomials and enriched with a C⁰(Ω) function. This approach leads to jumps in temperature gradient occurring only at the phase boundary, and is shown to significantly improve estimates for the front velocity. Temporal derivatives of the temperature field in the vicinity of the phase front are obtained with a projection that employs discontinuous enrichment. In conjunction with a finer finite difference grid, the Level Set method is used to represent the evolution of the phase interface. An iterative procedure is adopted to satisfy the constraints on the temperature field on the phase boundary. The robustness and utility of the method is demonstrated with several benchmark problems of phase transformation. Copyright © 2002 John Wiley & Sons, Ltd.     

浅谈课堂教学的自我反思

介绍了课堂教育反思的意义、途径和策略，指出了善于课堂反思是提高课堂教学水平、促进教师专业性发展的重要渠道。     

论社区服务产业化

社区经济作为一种优化的资源配置方式，利用社区服务为载体，将社区内互不相联的各种经济成份变为利益共同体，建立一种新的经济生产方式，从而带动社区乃至更广区域的经济发展。     

电厂热力系统耗差分析系统实现的研究与发展

总结了电厂热力系统耗差分析几种实现方式，回顾了国内在该领域的发展过程。电厂热力系统耗差分析实现方式分别经历了独立的耗差分析系统、基于DCS的耗差分析系统、基于MIS的耗差分析系统。并在不同的分析方式上进行了评价，指出了耗差分析系统的发展方向。     

Proactive resource allocation for asynchronous real-time distributed systems in the presence of processor failures

We present two proactive resource allocation algorithms, RBA^*-FT and OBA-FT, for fault-tolerant asynchronous real-time distributed systems. The algorithms consider an application model where task timeliness is specified by Jensen's benefit functions and the anticipated application workload during future time intervals is described by adaptation functions. In addition, we assume that reliability functions of processors are available a priori. Given these models, our objective is to maximize aggregate task benefit and minimize aggregate missed deadline ratio in the presence of processor failures. Since determining the optimal solution is computationally intractable, the algorithms heuristically compute sub-optimal resource allocations, but in polynomial time. Experimental results reveal that RBA^*-FT and OBA-FT outperform their non-fault-tolerant counterparts in the presence of processor failures. Furthermore, RBA^*-FT performs better than OBA-FT, although OBA-FT incurs better worst-case and amortized computational costs. Finally, we observe that both algorithms robustly withstand errors in the estimation of anticipated failures.