政府工程采购的发展情况及存在问题

政府采购机制是规范化我国政府投资建设项目管理的一个重要工作领域。文章针对我国政府采购和政府工程采购的基本发展情况进行了说明，并对政府工程采购发展过程中存在的主要问题进行了分析。     

浅谈房地产营销策划的几个问题

当前房地产业市场竞争十分激烈 ,房地产市场营销中不可避免地存在着一些问题 ,针对这些问题 ,探讨如何搞好房地产的营销策划 .     

澳大利亚的反田园诗

本文主要论述澳大利亚的反田园诗。它通过对一些原始而丑陋的自然物象的描写，揭示了宇宙的本质和人类的本质，进而反映了时空无限、存在与虚无以及美丑共存的哲学本质。     

论章黄学派的汉字系统观念

章黄学派从一开始就十分注重对汉字体系的系统性进行探索 ,从章太炎首创的“语根”说 ,到黄侃对“变易”和“孳乳”、“笔势”和“笔意”的深入阐释 ,从陆宗达的字源学研究 ,到王宁关于汉字构形学理论框架的建构 ,经过几代人的不断努力、不断完善 ,章黄学派的汉字系统观念已逐渐发展为一种科学系统的汉字理论 ,成为我国汉字学史上一条闪亮的红线     

论秘密拘留制度的改进

2012年3月14日,十一届全国人民代表大会第五次会议对刑事诉讼法的修订使秘密拘留浮出水面,由此引发了争议。由于我国的秘密拘留制度自身存在较多缺陷,目前受制于诸多因素,比较现实可行的方法是对秘密拘留制度加以改革与完善,主要思路是:秘密拘留的适用必须坚持相称性与必要性原则;建议将"不通知家属"的批准权移交人民检察院行使;严格限缩"不通知被秘密拘留人家属"的期间;拓展通知被秘密拘留人家属的内容;绝对禁止私设法外秘密拘留场所;改革错误秘密拘留赔偿制度;加强人民检察院对秘密拘留的控制和监督。     

Do resources of network members help in help seeking? Social capital and health information search

Does social capital as resources of network members affect health information search? Analyzing data from the 2004 General Social Survey in the United States, this study measures two social capital indicators (average education of network members and proportion of network members with a high school degree or higher) using the name generator. Most results are consistent using those two indicators. Both indicators are positively associated with frequency of health information seeking and seekers’ frequency of use of two sources (friends or relatives and the Internet). Also average education of network members is positively associated with seekers’ diversity of used sources and frequency of consultation with medical professionals. But neither indicator is associated with seekers’ frequency of use of other four sources (health-related magazines or newsletters, general magazines, daily newspapers, and radio or television programs). The findings demonstrate the theoretical utility of social capital in the social dynamics of medical help-seeking.     

Contents of heavy metals in arable soils and birth defect risks in Shanxi, China: a small area level geographic study

The burgeoning demands of China’s urbanization and industrial development put pressure on the resources of the entire country and have direct and indirect effects on the health of individuals, at times in areas far removed from cities themselves. Current evidence suggests that heavy metal pollution in soil, a common by-product of coal mining and other industrial activities, may be linked to risk of birth defects. We examine this hypothesis using small area level data including soil samples and detailed birth records from 2002 to 2004 from 97 villages in Shanxi province, a heavy coal-mining region. We find that soils containing arsenic, lead, and nickel are significantly correlated with the incidence of birth defects. In particular, we find a strong positive dose-dependent association of birth defects with lead, a moderate positive effect with arsenic, and a dose-dependent negative association with nickel. These results are consistent with the postulated link between arsenic and lead and human birth defects, but raise questions about the effects of nickel in this context. China’s rapid urbanization underscores the need for closer attention to the relationship between the health and the environment.     

A KNOWLEDGE-BASED DSS FOR MANAGERIAL PROBLEM DIAGNOSIS

A knowledge-based system supporting managerial problem diagnosis is described. The system provides the capability to monitor values of selected variables for problem situations. When problems are located, a list of problem symptoms is delivered to a problem processor for structuring and diagnosis. Problem structuring is based on a combination of concepts from expert systems and structural modeling. User assertions about cause-effect relationships between pairs of variables are maintained in a semantic network. Problem diagnosis uses the relationships in the semantic network to construct causation trees, the branches of which represent potential explanations of the problem symptoms. Mathematical models are constructed based on causation-tree branches, and values from the data base are used to test whether the model confirms the diagnosis. If so, the source of the problem has been located and it is then up to the user to resolve the problem. If the model fails to explain the problem, the model apparently is deficient and the user may perform “what if…” type scenarios in attempts to improve the model and search for problem causes. Realistic applications in the accounting and health care areas are discussed.     

The Invisible Village: An Exploration of Undergraduate Student Mothers’ Experiences

This study explored the experiences of mothers in college using a qualitative design. Results showed that a lack of financial resources was the chief barrier for student mothers in their educational pursuits while social/emotional support was the most important contributor to student mothers’ success in college. Participants relied heavily on student loans to cover costs of childcare or family to help watch their children. Role conflict experienced by student mothers has implications on family and college retention. Implications of this study included the adaptation and revisions of policies at the state and federal levels in addition to implications at the university level. Limitations of the study included a lack of racial and ethnic diversity and only including student mothers currently enrolled in college. Several recommendations for future research are described.     

单窃听双跳协作网络的中继选择方案及其性能分析

研究了安全通信意义下,单向译码转发（decode-and-forward,DF）协作无线网络的中继选择问题。针对窃听者既能获得信源发出的信号,又能窃取中继节点转发数据的通信系统,提出了3种中继选择方案来对抗窃听者,增强系统物理层安全性。其中,方案一选择到窃听者信噪比（signal-to-noise ratio,SNR）最小的中继节点;方案二为最大最小（max-min）选择方案,即选择信源到中继节点和中继节点到信宿的较差信噪比中最大值所对应的中继节点;方案三根据窃听信道和主信道的瞬时信道状态信息（channel state information,CSI）选择使得窃听网络有最大保密容量的中继节点。在对各方案的性能分析过程中,得到了各中继选择方案拦截概率的闭式表示,进一步对拦截概率作渐近分析,获得了各中继选择方案的分集阶数。具体地,方案一的分集阶数为1,另外2个中继选择方案的分集阶数均为中继节点个数M。数值结果验证了理论分析得到的结论。