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31.
This paper addresses the following subjects: biotechnology and consumers, concern about risks, consumer acceptance, labelling of foods produced using biotechnology, the legal approach to consumer protection, and consumer protection policies relating to biotechnology products in the European Union, the United States, Turkey and global institutions such as the Convention for Biological Diversity (CBD) and the World Trade Organisation (WTO). It is likely that biotechnology will gain ground much more rapidly in the twenty‐first century than in the past. Despite rapid, detailed and precise advances in gene technology, its applications have not been the received with a great deal of consumer enthusiasm. Consumers have approached genetically modified foods with considerable apprehension and opposition. Consumer concerns about bioengineered food products focus on the questions of human health, environmental and social risks and benefits. The most important stages in the process of marketing new foods produced using biotechnology are to demonstrate user need and consumer acceptance. Generally, the technical complexity of biotechnology makes it difficult for consumers to understand details of the product and the specific attributes of biotechnology applications. Scientific uncertainty, the nature of consumer concerns and general reluctance to accept biotechnology products, increase the importance of consumer protection. Legal protection is a very important factor in the solution of new social problems related to technological advances. More specifically, consumer and environmental law support consumer protection related to foods produced with biotechnology. The basic principles of consumer law can be re‐formulated as consumer rights. Environmental law is a new phenomenon, but precautionary principles and public participation in decision‐making for environmental law are relevant to consumer protection relating to bioengineered food products.  相似文献   
32.
Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.  相似文献   
33.
The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.  相似文献   
34.
1. Introduction The village election was first envisioned by the late chairman of the National People’sCongress (NPC), Mr Peng Zhen, in the mid-1980s to enhance village governance after the commune system was dissolved in China in the early 1980s. In 1987, the NPC passed a tentative version of The Organic Law of the Village Committee (OLVC), and started a 10 year experiment of village elections. In 1998, the NPC formally passed the law and elections quickly spread to the whole count…  相似文献   
35.
I model imperfect information, derive a downward sloping market demand curve, and explain vacancies in a partial equilibrium model of a rental housing market. Tenants can be completely described by an exogenous demand curve, perhaps arising from differences in income, preferred location, or tastes, and view vacant units based on a stochastic arrival of rental information. Free entry of these landlords induces excess rental housing capacity (equilibrium vacancies). I determine the equilibrium distribution of rents for vacant units, show that this rent distribution may be discontinuous, and explore the equilibrium vacancy rate to changes in exogenous parameters. The resulting characterization of equilibrium distributions of rents may be amenable to econometric modeling exploring the relationship between market rents and vacancies.  相似文献   
36.
罗赟 《物流科技》2007,30(11):12-14
随着近年流通领域的发展,尤其是电子商务对现代物流的要求,物流配送需要现代化的信息技术已越来越成为人们的共识,如何对物流配送系统和配送中心进行现代化建设,已成为不少物流配送公司的重要课题。针对目前物流配送中“不可见部分”和过程无法控制的现状,论文设计了一个物流配送实时监管系统来满足物流配送企业和客户的需求。  相似文献   
37.
上市公司股利分配现状及对策研究   总被引:2,自引:0,他引:2  
本文分析了我国上市公司股利分配的现状及存在的主要问题,并深入地剖析了这些问题产生的原因。在此基础上,从内部规范和外部规范两个方面提出改进我国上市公司股利分配的对策,以其对发展与完善我国资本市场提供帮助。  相似文献   
38.
丁勇 《物流科技》2004,27(1):24-26
物流配送是一个涉及多种影响因素的综合性复杂问题。本文探讨了基于Agent(智能体技术)的物流配送决策支持系统设计,在该系统中的智能体模型中引入学习机制,初步建立了一个具有专家系统特点、可以不断进化的物流配送决策支持系统。  相似文献   
39.
Recent work on social status led to derivation of a new continuous distribution based on the exponential. The new variate, termed the ring(2)-exponential, in turn leads to derivation of two closely related new families of continuous distributions, the mirror-exponential and the ring-exponential. Both the standard exponential and the ring(2)-exponential are special cases of both the new families. In this paper, we first focus on the ring(2)-exponential, describing its derivation and examining its properties, and next introduce the two new families, describing their derivation and initiating exploration of their properties. The mirror-exponential arises naturally in the study of status; the ring-exponential arises from the mathematical structure of the ring(2)-exponential. Both have the potential for broad application in diverse contexts across science and engineering. Within sociobehavioral contexts, the new mirror-exponential may have application to the problem of approximating the form and inequality of the wage distribution.  相似文献   
40.
物流配送系统中的运筹学问题及方法研究   总被引:1,自引:1,他引:1  
任志霞 《物流科技》2007,30(3):10-12
物流配送系统中包含诸多运筹学问题,如配送中心选址中的0-1规划问题,货物配载中的背包问题,配送路线优化中的动态规划问题等,通过建立数学模型,利用运筹学方法与信息技术的结合可对上述问题加以解决,为配送业务的进一步发展提供帮助.  相似文献   
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