浅谈建筑工程施工质量问题产生原因

针对当今建筑业的实际情况，结合施工管理经验，对建筑工程施工质量问题的产生原因作一简单的分析与阐述，通过对导致建筑工程施工质量问题的市场原因和形势原因进行分析，以达到促进建筑业发展的目的。     

当前建筑企业潜亏的思考

阐述了建筑企业潜亏的现状,分析了建筑企业潜亏的原因,探讨了潜亏对建筑企业发展的不利影响,提出了解决建筑企业潜亏的建议与对策,以最大限度地避免潜亏,从而为建筑企业持续、健康发展奠定基础。     

Sharing Rivers for Peace,Development, and Security

Abstract

Water is a finite resource, and with the considerable upsurge in population, urbanization, and industrialization, it is also becoming an increasingly scarce resource. Many countries in the world rely on river waters, and many of those rivers are shared by two or more countries. Dams on those rivers have been a major source of tensions, disputes, and, in some cases, even conflict between riparian countries because dams could result in massive diversion of river flows. Those developments have, inter alia, highlighted the relevance and importance of the principles of international water law, as reflected in the United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses. The World Commission on Dams has also underscored the importance of, and elaborated on, those principles with regard to dams on shared rivers. This article discusses and analyzes the recommendations of the Commission in this area, and compares them with the principles of international water law as enunciated in the United Nations Convention     

Second law analysis of a natural gas‐fired gas turbine cogeneration system

The influence of operating conditions such as reheat, intercooling, ambient temperature and pressure ratio are analyzed from a second law perspective on the performance of a natural gas‐fired gas turbine cogeneration system. The effect of these operating parameters on carbon dioxide emissions is also discussed. The second law efficiency of gas turbine cogeneration system increases markedly with reheat option. Higher pressure ratios lead to decreased second law cogeneration efficiency but this effect can be reduced with a higher level of reheat option. The effect of intercooling on second law efficiency is strongly related to pressure ratio with higher pressure ratios significantly decreasing efficiency. The second law efficiency is not so sensitive to the environment temperature for levels of reheat or intercooling greater than 50%. Copyright © 2009 John Wiley & Sons, Ltd.     

试论中国铁矿业崛起与未来的发展规划（二）

从资源分布、铁矿床类型、铁矿产量、露天和地下开采技术、选矿技术、矿山装备等方面,全面论述了我国铁矿业的崛起和现状,提出了我国2010—2015在铁矿产量、勘查力度、环境保护及恢复安全生产,建立现代化、绿色、数字化矿山方面的发展规划。     

河南省职业院校女生课余体育锻炼现状调查与分析

运用文献资料法、问卷调查法和数理统计法，对河南省职业院校女生课余体育锻炼现状进行调查和分析，对其存在问题进行探讨，以此提出与之相关的建议和解决办法，为进一步提高河南省职业院校女生课余体育锻炼水平和质量提供借鉴。     

起伏地形点电源地下传导电流磁场表达式——磁电阻率法地形改正

修正的毕奥-沙伐尔定律完全适用于任意起伏地形的情况。任意地形点电源地下传导电流产生的磁场,可以写成传导电流的电位在地形边界面上的面积分形式。若为二度地形,沿其走向作一维富氏变换,可把面积分形式转换成波数域的线积分形式。利用有限单元法、有限差分法等数值计算方法可以计算任意地形传导电流的磁场。     

m值随机变量序列的几个强大数定律

本文的目的是要引进m值随机变量序列相对于独立分布的随机比较系数的概念,并利用这个概念给出关于给定值在此序列中出现频率的几个强大数定律。     

模型参考自适应控制系统的稳健性分析

本文对高频寄生,外部干扰及高频参考输入共存的模型参考控制系统进行了稳健性分析。采用Narendra直接法设计思想,利用Ioannou修改的自适应律,给出了状态偏差,寄生变量和失配参数向量的有限上界。     

高登粒度特性方程式的参数及变化规律研究

磨矿产品粒度特性方程式的参数不可能是常数,而是一个变数.它随矿石性质及磨矿粒度粗细而变化.本文中通过实际矿物磨碎试验而研究细磨及超细磨下高登粒度特性方程式参数k的意义及变化规律.