基于随机二元指标的边坡稳定性分析

考虑岩土体抗剪强度参数的变异性,综合极限平衡法和可靠性理论构建了安全系数概率密度分布函数模型。结合实际工程特点,以安全系数大于临界值为标准构建有效区,将有效区安全系数均值与对应可靠度相乘,得到以安全系数和可靠度为随机二元指标的有效安全系数。以有效安全系数为定量指标,将边坡宏观特征现象与定量分析相联系,构建意义更为明确的边坡稳定性分析及评价方法。通过工程实例对比了有效安全系数与传统评价指标之间的差异。所得结论可为工程建设提供参考和借鉴。     

抗滑桩设计推力计算方法研究

滑坡推力是抗滑桩设计推力的重要依据,工程中通常使用剩余推力法来计算滑坡推力。为了比较准确合理地计算出抗滑桩的设计推力,提出了在剩余推力法基础上的一种新的抗滑桩设计推力取值方法。分析极限平衡状态下和工程安全要求下各条块的剩余下滑力,选择合理的桩位,使得抗滑桩位于滑坡体的抗滑段;然后调整桩后滑体的剩余下滑力,其调整量一方面保证桩前桩后滑体满足工程安全要求,另一方面则作为抗滑桩设计推力的修正依据,其过程由程序实现。通过实例证明了该方法的合理性。同时对今后抗滑桩设计推力的合理取值提供了参考作用。     

青藏铁路冻土区环境问题对工程安全可靠性影响

本文分析了青藏铁路冻土区主要工程对多年冻土温度、水分特征和冻土环境特征的影响,探讨了冻土区工程环境与冻土环境之间相互作用特点。进而论述了控制外界对冻土工程环境系统的热侵蚀是保证冻土区工程安全可靠性的关键问题。     

中国蔬菜生产的农业物质投入及其潜在风险评价（英文）

由于蔬菜需求量的增加,中国的蔬菜产量不断增加;然而蔬菜地的化学污染会威胁到中国的食品安全。基于蔬菜和粮食作物的播种面积和产量、农业生产投入价格指数、单位面积的农业物质投入、蔬菜和粮食作物生产者价格指数和净利润等数据,本文计算分析了蔬菜地污染造成的中国潜在食品安全风险的变化趋势。研究表明,由于改革开放以来对蔬菜饮食的公共需求的不断增加和蔬菜高的市场价格,蔬菜的播种面积和产量显著增加;然而由于研究时段内蔬菜种植比例的增加,农业物质投入增加所带来的潜在污染风险也在不断增加。通过控制蔬菜地污染,中国的食品安全问题可以得到较大改善。     

Governance Logic and Basic Systems of the New “Food Safety Law of the People’s Republic of China”: a Focus on Social Co-Governance

To modernize food safety governance, we must carry out basic restructuring of its internal logic at the national level to reflect the features of contemporary Chinese society that shape food safety. This will entail establishing an overarching, macro-level conception of food safety that integrates “baseline safety”, “hub safety”, “co-constructed safety” and “endogenous safety”. These four dimensions of safety represent four fundamental requirements of food safety governance in modern Chinese society, which is a “risk society” (Beck 1992) and one that is also complex, open and pluralist. These requirements are: maximum legal liability, a unified, authoritative and efficient supervision system, a concept of social co-governance, and enterprises being the primary entities accountable for food safety. This article uses this analytical framework to interpret the basic contents of the newly revised Food Safety Law of the People’s Republic of China, and uses a focus on social co-governance to present the institutional highlights of this law and the transformation of the internal logic of food safety governance.     

Design and Implementation of the Hydrographic Production and Management Information System (HYPAMIS)

With the development of hydrographic work and information techniques, the traditional work mode is not suitable for the Chinese Marine Safety Administration Bureau (CMSAB). Aiming at the separation of charts production and management, a new idea that is the integration of production, management, and quality control is presented. Geographic Information System (GIS), Management Information System (MIS), Office Automation (OA) and Spatial Database Management (SDM) advanced techniques are introduced into the workflows in CMSAB. To realize information sharing, a mixed mode with Browser/Server (B/S) mode and Client/Serve (C/S) mode are adopted. Based on the above ideas and strategies, an integrated system named Hydrographic Production And Management Information System (HYPAMIS) was developed. The whole workflow and three subworkflows including survey management workflow, production workflow, and quality control workflow of are outlined after re-engineering the CMSAB organization. Some design principles and key techniques of the HYPAMIS including the cooperation of GIS and MIS, object-oriented spatial data model and management, data management based on database, and security control are illustrated in detail. Then the implementation of the system is introduced briefly. Finally, performance evaluation of the system and future work is given.     

Assuring fish safety and quality in international fish trade

International trade in fishery commodities reached US 58.2 billion dollars in 2002, a 5% improvement relative to 2000 and a 45% increase over 1992 levels. Within this global trade, developing countries registered a net trade surplus of US 17.4 billion dollars in 2002 and accounted for almost 50% by value and 55% of fish exports by volume. This globalization of fish trade, coupled with technological developments in food production, handling, processing and distribution, and the increasing awareness and demand of consumers for safe and high quality food have put food safety and quality assurance high in public awareness and a priority for many governments. Consequently, many countries have tightened food safety controls, imposing additional costs and requirements on imports. As early as 1980, there was an international drive towards adopting preventative HACCP-based safety and quality systems. More recently, there has been a growing awareness of the importance of an integrated, multidisciplinary approach to food safety and quality throughout the entire food chain. Implementation of this approach requires an enabling policy and regulatory environment at national and international levels with clearly defined rules and standards, establishment of appropriate food control systems and programmes at national and local levels, and provision of appropriate training and capacity building. This paper discusses the international framework for fish safety and quality, with particular emphasis on the United Nation's Food and Agricultural Organization's (FAO) strategy to promote international harmonization and capacity building.     

核电厂设计地震动评定中的构造法和概率法结果比较

剖析和比较了地震危险性分析方法(综合概率法)和地震构造法的结果,认为,不能简单将构造法的结果作为概率法的上限,也不能确定在10-4的概率水平上,概率法结果就比构造法结果大,因此评定核电厂极限安全地震应同时使用构造法、概率法和其它方法,并取各种结果的最大值     

砂土液化的尺度与概率

本文以液化安全间距及安全系数为随机变量进行了可靠性分析,给出了衡量砂土液化严重程度的尺度及相应的液化概率,并提出了对砂土液化严重程度进行分级的建议。     

区域地壳稳定性研究的后顾与前瞻

文章回顾了中国区域地壳稳定性研究的历史,划分了其发展阶段,阐述了不同学派的基本观点,分析了该领域面临的新挑战并指出了其未来的发展方向。明确提出,在活动地区选出并评价相对稳定地块(安全岛)作为重大工程场址将是未来的主流。