Estimation of urbanization bias in observed surface temperature change in China from 1980 to 2009 using satellite land-use data

Since the 1980s,China has undergone rapid urbanization.Meanwhile,the climate has been warming substantially.In this paper,the urbanization effect on observed temperatures from 1980 to 2009 in China is estimated,based on analysis of urban land use from satellite observation.Urban land-use expansion(U) during 1980-2005 is applied as an urbanization index.According to these U values,stations are divided into three categories:(C1) intense urbanization around the stations;(C2) moderate urbanization around the stations;and(C3) minimal urbanization around the stations.Most C1 stations are in municipalities or provincial capitals,while C2 stations tend to be in prefecture-level cities.C3 stations are mostly in counties.The urban heat island(UHI) effect can be estimated if the urban effect on C3 is negligible.The warming of C1 or C2 relative to that of C3 represents their urbanization effects,assuming that the same larger-scale natural warming has affected each category.For C1,the local urbanization effect is 0.258°C/10 a over 1980-2009,accounting for 41% of the total warming;the trend at C2 is 0.099°C/10 a,or 21%.For all China,the urbanization effect is 0.09°C/10a,accounting for 20% of the total national warming.Winter urban warming is greater than in summer.The assumption of negligible urbanization effect on C3 is debatable,and so the true urbanization effect may equal or slightly exceed estimates.Further,the U index may have some uncertainties,for it is only one of the urbanization indices.However,it provides a new and direct estimation of environmental change,in contrast to indirect indices.     

Optimization criteria for the performance of heat and mass transfer in indirect evaporative cooling systems

The wide application of evaporative cooling techniques in which the optimization criteria form the theoretical basis for improving evaporative cooling performance is essential for energy conservation and emission reduction.Based on exergy analysis and the entransy dissipation-based thermal resistance method,this contribution aims to investigate the effects of flow and area distributions in the optimization of the performance of indirect evaporative cooling systems.We first establish the relationships of exergy efficiency,entransy dissipation-based thermal resistance and cooling capacity of a typical indirect cooling system.Using the prescribed inlet parameters,the heat and mass transfer coefficients and the circulating water mass flow rate,we then numerically validate that when the cooling capacity reaches a maximum,the entransy dissipation-based thermal resistance falls to a minimum while the exergy efficiency is not at an extreme value.The result shows that the entransy dissipation-based thermal resistance,not the exergy efficiency,characterizes the heat transfer performance of an evaporative cooling system,which provides a more suitable method for evaluating and analyzing the indirect cooling system.     

安徽沙溪式斑岩铜(金)矿床地质地球化学特征及成因分析

沙溪斑岩铜(金)矿床位于庐枞火山岩盆地西北外围,处于郯庐断裂带内部.矿体主要产于燕山期的石英闪长斑岩,次为黑云母石英闪长斑岩中.主要成矿期为岩浆期后热液期.蚀变分带自内向外:钠-更长石化带—硬石膏-黑云母-钾硅酸盐化带—钾硅酸盐青磐岩化叠加带—石英绢云母化带—青磐岩化带,主要工业矿体位于钾硅酸盐化带及其外侧.文章总结沙溪式斑岩铜(金)矿床地质地球化学特征,并对该类型铜(金)矿床的成因进行了探讨.     

资源型企业技术创新管理的复杂性及协同研究

着力挖掘资源型企业技术创新及其管理的复杂性来源及特点,以准确反映其创新本质和规律。基于系统研究的视角,运用协同理论确立了资源获取与控制能力、动态整合能力和创新实现能力作为支配役使资源型企业技术创新管理系统演化和发展的序参量,从而为使技术创新活动走向更高级的有序阶段,建立起科学有效的技术创新管理模式提供理论指导。     

网络故障边的权重优化分配与比例分配策略比较分析

边的故障可通过级联效应给网络带来灾难性后果.如何减弱或避免故障带来的影响成为目前研究的重点.当网络中某边出现故障后,需对故障边的边权进行分配,该文提出一种优化分配模型,模型中考虑了对点权大的节点的保护,常用的比例分配方案是优化分配模型的一个可行解.实例分析表明,采用优化分配策略有时可完全避免级联失效的发生,并指出不同的攻击策略下,易选取不同的故障边边权分配方案.     

生态适宜性评价方法在城市规划中的应用——以平顶山市新城区为例

以平顶山市新城区为例,对生态适宜性评价方法在城市规划中的应用进行了说明,通过分析可知平顶山市新城区生态适宜度综合评价值为2.05,属基本适宜范围.影响生态适宜度评分的主要因素为工业和生活组团的布局,跟当地大气环境质量较差、湛河水质超标也有关系.     

船体结构粘弹性夹层阻抑振动波传递特性研究

基于波动理论分析了含粘弹性材料夹层的船体板架中振动波传递特性,给出粘弹性夹层对弯曲波的隔声量公式.同时将粘弹性夹层引入转角含阻振质量的典型船舶L型结构中,通过多次构造阻抗失配有效地阻断船体振动噪声主分量的传递.在此基础上,将这种复合隔振技术引入到动力舱段声学设计中并开展相应的数值实验.结果表明:粘弹性夹层对船体结构波具有较强的阻抑作用,夹层隔振性能随其杨氏模量降低及尺度增加而增大,夹层杨氏模量对隔声量的影响较其尺度更为显著,在刚性隔振基础上联合应用较小尺度的聚氨酯夹层可显著增加隔振效果并有效拓宽了隔振频带,具有较高的效费比.     

从文献计量分析看我国自学考试的发展

对1981—2010年30年间我国关于自学考试的研究论文从数量分布、年代分布、期刊分布、作者和作者机构分布等方面进行了文献计量学分析,探讨了自学考试研究的发展趋势。     

浅析基于WinCC的煤矿主扇风机监控系统

为了实现对煤矿主扇风机运行状况的实时监测及实现对风机的远程控制,选用一套基于WinCC组态软件的煤矿主扇风机监控系统,实现了对风机的实时监控和远程控制。本监控系统操作方便,能够及时提供动态信息,具有较高的可靠性和灵活性。     

高校图书馆勤工俭学工作的思考

高校图书馆开展勤工俭学工作,既有利于图书馆管理和服务升级,又有利于学生缓解经济压力。阐述了高校图书馆开展勤工俭学工作的意义,介绍了高校图书馆勤工俭学工作的内容,针对高校图书馆勤工俭学工作存在的问题,提出了加强勤工俭学工作的管理,促进勤工俭学工作良性发展的措施。