开发基于GIS的城市防震减灾信息系统 --组件对象模型的应用

应用GIS建立城市防震成灾信息系统是一条减轻城市地震灾害的有效途径,而现有的城市防震减灾信息系统中防震减灾专业模型与GIS功能结合不够紧密,因此加强对地震灾害智能计算的研究十分重要。文章分析了城市防震成灾信息系统常用的二次开发方法,阐述了组件对象模型(COM)技术及其在系统开发中的应用方法,论述了应用COM技术开发系统的界面与功能等。     

企业资源管理拓展问题评述

企业资源管理问题是关系到提升企业核心价值和保持企业持续竞争优势的重要问题，企业资源管理的拓展是企业管理理论和实践的共同需要。在文献综述的基础上，从企业广义资源环境划分、企业资源管理范畴拓展、企业资源形式和属性等几个不同角度，对企业资源管理拓展问题进行了讨论和分析。     

组合优化的能源消费量预测模型

针对非等间距灰色系统预测中存在误差较大的问题，结合序列本身的特点，利用世界能源消费的历史数据，采用3种灰色预测模型与神经网络进行组合优化，建立了灰色神经网络的能源消费量组合预测模型。实证分析结果表明，提高了模型的拟合和预测精度，拓宽了应用范围。该模型可对能源的消费趋势进行预测，为科学分析能源结构提供依据。     

我国城市生活垃圾的处理和发展趋势

城市生活垃圾给城市环境造成了严重污染，威胁了城市居民的生存环境和经济、社会的可持续发展。目前，国内采取的垃圾处理技术主要有卫生填埋、焚烧、堆肥等，热解技术由于具有资源回收率高、二次污染小、综合效益好等优点，越来越适合我国中小城市的垃圾处理。垃圾气化技术的研究成为当今世界的热点。此外，我国对垃圾衍生燃料的研究也刚刚起步。为促进城市持续、稳定的发展，提出了垃圾分类收集、分拣、综合利用垃圾处理技术的措施。     

轴心受压钢筋混凝土柱等效火灾荷载的计算

迄今为止，国内外有关计算构件耐火极限的方法，是钢筋混凝土构件与防火研究的主要内容。而在结构设计中，由于直接考虑的是荷载作用，为此提出了一个新概念——等效火灾荷载，将火灾对结构的影响直接考虑成荷载作用。在确定了混凝土柱的截面温度场后，利用一种简化计算方法计算出钢筋混凝土柱的等效火灾荷载，进而计算出钢筋混凝土柱的耐火极限。在火灾中，作为结构最基本的构件柱可能受到单面或多面的火作用，这里仅介绍轴心受压钢筋混凝土柱等效火灾荷载的计算。     

我国民航灾害应急联动机制优化研究

针对我国现行的民航灾害应急联动救援体系所存在着多头指挥、组织形式不明确、责任关系不协调、信息沟通不顺畅、资源调度不合理等问题,运用文献检索、理论分析与实地调研相结合的方法,笔者提出优化思路:民航灾害应急联动机制应以各级民航管理当局的飞行事故应急指挥部为主要指挥决策者,采用虚拟的网络式组织形式,理顺联动单位的责任与关系,将应急联动的信息网络与各地突发公共危机事件的信息平台接轨,成立全国统一的、具有双重功能的民航灾害应急资源调度中心。其中,对民航灾害应急联动虚拟网络组织形式的设计,较好地改进了现行组织的效率,体现了快速反应和协调行动的要求。     

US/Fenton试剂协同处理焦化废水的研究

采用US (超声波)协同Fenton试剂氧化法处理焦化废水,考察了H2O2投加量、Fe2 投加量、废水的pH、反应时间和超声波功率对处理效果的影响,确定了最佳工艺条件.结果表明,在H2O2投加量7.0 g/L;Fe2 投加量500 mg/L;pH=3.0; 反应时间 40 min; 超声波功率 600 W 的条件下,COD、NH3-N、CN-和色度的去除率分别达95.8%、71.3%、69.5%和75.2%,出水COD降至41.0 mg/L.在相同条件下,US/Fenton试剂协同法的处理效率比单独Fenton试剂氧化法的处理效率提高了约20%,且反应时间显著缩短.     

Assessing the sustainability of major cities in China

Rapid urbanization in the developing world calls for attention to address the issue of urban sustainability, especially in emerging countries such as China, where social equity and environmental conditions have been marginalized by the rapid economic development. In this paper, we addressed the above issue with an attempt to answer the following questions: (1) How did the sustainability of Chinese cities evolve over time? (2) What are the driving forces for the evolution? By constructing a composite index that incorporates three major aspects of sustainability, economy, environment, and social equity, we characterized the recent evolution of Chinese cities and assessed the disparity among regions in terms of the sustainability measures. Further, we analyzed the driving forces for the change of sustainability indices through a driving force-pressure-state-effect model. We substantiate our numerical analysis of Chinese cities with a detailed case study of Urumqi, the capital of Xinjiang Autonomous Region, which has experienced significant change over the past 3 decades in every aspect of sustainability. We highlight some fundamental socioeconomic driving forces that have caused spatial restructuring, reflected by land-use change, and consequently impacted the urban environment of Urumqi. A brief case analysis of Guangzhou is also provided.     

The fragmentation patterns of maternal plasma cell-free DNA and its applications in non-invasive prenatal testing

The discovery of cell-free DNA (cfDNA) in maternal plasma has opened up new promises for the development of non-invasive prenatal testing (NIPT). Application of cfDNA in NIPT of fetus diseases and abnormalities is restricted by the low amount of fetal DNA molecules in maternal plasma. Fetus-derived cfDNA in maternal plasma are shorter than maternal DNA, thus leveraging the maternal and fetus-derived cfDNA molecules size difference has become a novel and more accurate method for NIPT. However, multiple biological properties such as size distribution of plasma DNA, proportion of fetal-derived DNA and methylation levels in maternal plasma across different gestational ages still remain largely unknown. Further insights into the size distribution and fragmentation pattern of circulating plasma cfDNA will shed light on the origin and fragmentation mechanisms of cfDNA during physiological and pathological processes in prenatal diseases and enhance our ability to take the advantage of plasma cfDNA as a molecular diagnostic tool. In the review, we start by summarizing the research techniques for the determination of the fragmentation profiles of cfDNA in maternal plasma. We then summarize the main progress and findings in size profiles of maternal plasma cfDNA and cffDNA. Finally, we discuss the potential diagnostic applications of plasma cfDNA size profiling.