食品安全监管制度的优化及其实现逻辑--基于上海羊肉掺假的个案分析

食品安全监管制度是政府及其相关者行为规范和行为模式的总和。制度的主要作用是协调不同主体之间的行为,最终实现彼此间的共同利益,因而政府采取沟通、联合、互动的方式平衡彼此之间的关系,防止食品安全监管出现混乱无序的状态。但我国食品安全监管制度一直处于变迁之中,食品安全事故屡见不鲜,在现有的制度环境之下,难以协调一致来实现食品安全的目标。以上海羊肉掺假事件为个案,从个体行为层次与体制秩序层次分析事件的内在机理及其产生根源,并在“大部制”改革的前提下,通过制度优化来约束、激励、规范食品安全各利益主体的策略行为。     

我国食品安全信用规制的法学反思与完善

我国食品安全领域失信危机已成为广泛关注的社会问题,反映在法律制度上就是经营者、监管者对公众承负的食品安全信用义务的法律化程度低,信用关系依附消费合同和行政法律关系挑战着公众法律地位。通过法律之力建构独立的食品安全法律关系,在安全标准和信息披露制度等中体现公众意志是实现食品安全信用法治的必由之路。     

铸造Al-Si合金中Sr与B间反应产物的研究

通过观察不同Sr,B含量时Al-Si合金中枝晶α和共晶Si形态与大小的变化，考察了Sr,B间的交互作用，采用X射线能谱仪对反应产物进行了分析。研究表明反应产物呈现两种不同类型：当Sr含量在0.025-0.030,B含量在0.028-0.036（质量分数，％）范围内时，二者间交互作用形成细小的SrB6化合物颗粒相，数量很少，存在于枝晶α中心；但当合金中Sr和B含量高于此范围时，形成Sr,B原子比接近3：4的Sr-B化合物，颗粒尺寸大、数量较多，且大多出现在共晶区。Sr-B化合物的形成消耗了大量的Sr和B,削弱了二元素的变质效果，导致了Sr,B间的互毒化行为。该化合物的形成为Sr,B间互毒化机理提供了直接证据。     

基于Android平台的保健食品移动监管系统

针对保健食品企业监管效率低以及管理模式的不健全, 提出一种基于Android平台的移动监管系统模式. 智能终端设备通过连接3G、4G等无线网络, 使监管人员在执法现场将采集的信息数据直接上传至服务器, 同时增设数据同步代理机制, 实时监听用户的离线和在线状态, 防止数据丢失, 再利用蓝牙无线通信技术实现监管数据的后台打印功能, 进一步简化执法流程. 本系统的应用实现了移动监管和移动办公的模式, 具有实际应用价值.     

Food-water security and virtual water trade in the Middle East and North Africa

The purpose of this study is to analyze the political economy of food-water security in the water-scarce Middle East and North Africa region. The study deploys the lens of virtual water trade to determine how the region's economies have met their rising food-water requirements over the past three decades. It is shown that the region's water and food security currently depend to a considerable extent on water from outside the region, ‘embedded’ in food imports and accessed through trade. The analysis includes blue (surface and groundwater) and green water resources.     

Microsoft Windows vs. Apple Mac OS X: Resilience against ARP cache poisoning attack in a local area network

ABSTRACT

Robust security measures are integrated into new release versions of operating systems (OSs) to ensure that users have a more secure and reliable environment in which to run their daily tasks. In this article, through extensive practical experiments, we evaluate and compare the resilience of popular versions of Microsoft Windows OSs and Apple Mac OS X against Address Resolution Protocol (ARP) cache poisoning attack in a local area network (LAN). The experimental results demonstrate clearly that all tested versions of Windows OSs and Apple Mac OS X are vulnerable to the ARP cache poisoning attack, and do not deploy built-in efficient security features to prevent success of this attack. In addition, the experimental results directly contradict the common belief that Windows OSs are always less secure than Apple OSs. On the other hand, the article analyzes the efforts that have been made and the different methods that have been applied to detect and prevent ARP cache poisoning attacks. The article shows that none of these efforts and methods has been able to give satisfactory results.     

Establishing spatial trends in water chemistry and stable isotopes (δ15N and δ13C) in the Elwha River prior to dam removal and salmon recolonization

Two high‐head dams on the Elwha River in Washington State (USA) have changed the migratory patterns of resident and anadromous fish, limiting Pacific salmon to the lower 7.9 km of a river that historically supported large Pacific salmon runs. To document the effects of the dams prior to their removal, we measured carbon and nitrogen stable isotope ratios of primary producers, benthic macroinvertebrates, and fish, and water chemistry above, between and below the dams. We found that δ¹⁵N was significantly higher in fish, stoneflies, black flies, periphyton and macroalgae where salmon still have access. Fish and chloroperlid stoneflies were enriched in δ¹³C, but the values were more variable than in δ¹⁵N. For some taxa, there were also differences between the two river sections that lack salmon, suggesting that factors other than marine‐derived nutrients are structuring longitudinal isotopic profiles. Consistent with trophic theory, macroalgae had the lowest δ¹⁵N, followed by periphyton, macroinvertebrates and fish, with a range of 6.9, 6.2 and 7.7‰ below, between, and above the dams, respectively. Water chemistry analyses confirmed earlier reports that the river is oligotrophic. Phosphorous levels in the Elwha were lower than those found in other regional rivers, with significant differences among regulated, unregulated and reference sections. The removal of these dams, among the largest of such projects ever attempted, is expected to facilitate the return of salmon and their marine‐derived nutrients (MDN) throughout the watershed, possibly altering the food web structure, nutrient levels and stable isotope values that we documented. Published in 2010 by John Wiley & Sons, Ltd.     

Food security problems in sub-Saharan Africa: Operations Research as a tool of analysis

For many years, the author has been involved in teaching and research in the use of Operations Research as a tool of analysis to study food security problems in sub‐Saharan Africa, in particular, grass root problems of poor farmers. The paper presents an introduction to the way Operations Research methods have been applied in case studies and research projects, and discusses in retrospect the author's views on the strengths and limitations of the application of Operations Research. The paper has in particular been written for people who are not familiar with applications of Operations Research in agriculture, and are interested to learn about its potential usefulness in practice. The retrospective part is largely based on food security studies in e.g. Tanzania, Burkina Faso, Bénin, Togo and Eritrea and on participation in several interdisciplinary research programmes in Africa.     

新的仿生算法:蟑螂算法

通过模拟蟑螂的觅食行为,提出蟑螂算法(Cockroach Swarm Optimization,CSO)。算法充分利用了蟑螂社会的平等特性和群体智慧。食物再分配、回巢等策略的使用使算法具有较强的全局搜索和局部搜索能力。以TSP问题为例对算法进行仿真测试,实验证明算法有效且优于存在的离散粒子群算法(Discrete Particle Swarm Optimization,PSO)。