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91.
92.
When allocating community-based health services for a geographically defined region, health planners are often faced with the serious conflict for improved health service and a limited budget. This paper extends the cost-based P-median location–allocation model (Daskin & Dean, 2005) to include a public service element and uses the non-inferior set estimation (NISE) method for evaluation of cost/service trade-offs. Service is measured by the percentage of demand volume that can be served within exogenously specified coverage distances. Importantly, we evaluate the efficiency (i.e. the relative cost and service) of the non-inferior solutions of our model using the commonly used “population-based” allocation policy as standard. Computational results illustrate the value of our model under several practical problem settings. 相似文献
93.
Meredith B. Nevers Murulee N. Byappanahalli Thomas A. Edge Richard L. Whitman 《Journal of Great Lakes research》2014
Monitoring beach waters for human health has led to an increase and evolution of science in the Great Lakes, which includes microbiology, limnology, hydrology, meteorology, epidemiology, and metagenomics, among others. In recent years, concerns over the accuracy of water quality standards at protecting human health have led to a significant interest in understanding the risk associated with water contact in both freshwater and marine environments. Historically, surface waters have been monitored for fecal indicator bacteria (fecal coliforms, Escherichia coli, enterococci), but shortcomings of the analytical test (lengthy assay) have resulted in a re-focusing of scientific efforts to improve public health protection. Research has led to the discovery of widespread populations of fecal indicator bacteria present in natural habitats such as soils, beach sand, and stranded algae. Microbial source tracking has been used to identify the source of these bacteria and subsequently assess their impact on human health. As a result of many findings, attempts have been made to improve monitoring efficiency and efficacy with the use of empirical predictive models and molecular rapid tests. All along, beach managers have actively incorporated new findings into their monitoring programs. With the abundance of research conducted and information gained over the last 25 years, “Beach Science” has emerged, and the Great Lakes have been a focal point for much of the ground-breaking work. Here, we review the accumulated research on microbiological water quality of Great Lakes beaches and provide a historic context to the collaborative efforts that have advanced this emerging science. 相似文献
94.
Gdel语言因语言成份复杂而缺乏严格的语义基础和成熟的编译器,因此推出后它一直发展缓慢。对此采用进化代数描述了其主要语言成分延迟声明语句的过程性语义,然后介绍了依据该语义的具体实现方法并给出运行流程图和C语言描述。最后通过一个例子来具体说明延迟计算在基于扩展Warren机的编译系统中的执行情况。实验结果表明了其可行性。 相似文献
95.
Wim Verbeke Federico J.A. Pérez-Cueto Marcia D. de Barcellos Athanasios Krystallis Klaus G. Grunert 《Meat science》2010
This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries. 相似文献
96.
紫花苜蓿生物活性与应用的研究现状 总被引:2,自引:0,他引:2
紫花苜蓿的茎、叶中含有多种营养素及未知生长因子,紫花苜蓿次生代谢物具有多种独特的生物活性,如抗氧化、抑菌等。本文简述了紫花苜蓿叶蛋白、皂苷、类黄酮、膳食纤维等主要活性成分及其营养保健作用,并谈及紫花苜蓿活性成分营养保健的应用前景。 相似文献
97.
98.
远红外织物的保健性能 总被引:3,自引:2,他引:3
远红外织物是80年代中期研究开发出的一种通过高效吸收和发射远红外线而具有改善微循环、促进血液循环等功能的新型纺织品。本文通过研究实例综述了国内外近年来对远红外织物保健性能的研究成果。 相似文献
99.
针对智慧健康(S-health)中个人健康档案(PHR)的隐私保护问题,提出了一种外包解密可验证并可代理的基于属性的访问控制方案。首先,利用密文策略属性基加密(CP-ABE)方法,实现PHR的细粒度访问控制;其次,通过将复杂的解密计算外包至云服务器,并利用授权机构来验证云服务器返回的部分解密密文(PDC)的正确性;然后,基于代理方法,受限用户可将外包解密及验证委托给第三方用户执行而不泄露隐私;最后,在标准模型下证明了方案的自适应安全性。理论分析结果表明,用户端解密仅需执行一次指数运算,该方案具有较强的安全性与实用性。 相似文献
100.
Muhammad Yaseen Kashif Saleem Mehmet A. Orgun Abdelouahid Derhab Haider Abbas Jalal Al-Muhtadi Waseem Iqbal Imran Rashid 《Telematics and Informatics》2018,35(4):702-726
Recent advances in hardware technology have led to the development of low cost, power efficient and more feature rich devices that are amongst the most critical parts of communication networks. These devices or sensors can now sense data with more accuracy, process it by themselves and send it to the neighboring node or the sink node. However, robust and reliable security mechanisms are not yet properly implemented on these sensors due to their limited energy and computation power. Sensors also play a very important role in eHealthcare systems where ubiquitous patient monitoring is performed. As data is generated from the sensor nodes, reliable, secure and attack-resistant data acquisition and transmission is important for an efficient eHealthcare systems. This survey focuses on security issues of sensors data acquisition and transmission protocols, describing their main security features and comparing them in the context of a secure eHealthcare system. A taxonomy of open issues and future challenges is also discussed with respect to specific security metrics described in the paper. 相似文献