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171.
Heitor de Oliveira Duarte Enrique Lopez Droguett Márcio das Chagas Moura Elainne Christine de Souza Gomes Constança Barbosa Verônica Barbosa Moacyr Araújo 《Risk analysis》2014,34(5):831-846
We developed a stochastic model for quantitative risk assessment for the Schistosoma mansoni (SM) parasite, which causes an endemic disease of public concern. The model provides answers in a useful format for public health decisions, uses data and expert opinion, and can be applied to any landscape where the snail Biomphalaria glabrata is the main intermediate host (South and Central America, the Caribbean, and Africa). It incorporates several realistic and case‐specific features: stage‐structured parasite populations, periodic praziquantel (PZQ) drug treatment for humans, density dependence, extreme events (prolonged rainfall), site‐specific sanitation quality, environmental stochasticity, monthly rainfall variation, uncertainty in parameters, and spatial dynamics. We parameterize the model through a real‐world application in the district of Porto de Galinhas (PG), one of the main touristic destinations in Brazil, where previous studies identified four parasite populations within the metapopulation. The results provide a good approximation of the dynamics of the system and are in agreement with our field observations, i.e., the lack of basic infrastructure (sanitation level and health programs) makes PG a suitable habitat for the persistence and growth of a parasite metapopulation. We quantify the risk of SM metapopulation explosion and quasi‐extinction and the time to metapopulation explosion and quasi‐extinction. We evaluate the sensitivity of the results under varying scenarios of future periodic PZQ treatment (based on the Brazilian Ministry of Health's plan) and sanitation quality. We conclude that the plan might be useful to slow SM metapopulation growth but not to control it. Additional investments in better sanitation are necessary. 相似文献
172.
将SAO语义结构信息引入技术伙伴识别选择过程中,构建基于SAO语义分析的技术合作伙伴识别体系,通过对企业进行技术愿景分析、企业知识库分析确定技术合作网络,对网络内企业重点子技术领域进行相似度分析,从而识别企业潜在的技术合作伙伴,并制定针对性的合作方案。以染敏太阳能电池为案例开展实证研究,验证了该方法体系的可行性。 相似文献
173.
十年来中国社会保障建设取得了很大的成就,社会保障成为改善民生和社会建设重要领域和促进力量,对于克服经济全球化深入发展背景下各种矛盾、促进经济发展和社会稳定发挥着积极的作用。但是,中国社会保障制度还不完善,面对世界贸易组织框架下越来越复杂的国际国内形势,需要进一步加快社会保障制度建设,选择科学合理的社会保障模式和管理体制,加强社会保障公共服务体系建设,实现人人享有社会保障。 相似文献
174.
Shirley Musich Ronald J. Ozminkowski Frank G. Bottone Jr. Kevin Hawkins Shaohung S. Wang Janelle G. Ekness 《Journal of women & aging》2014,26(2):146-159
Numerous barriers to managing coronary artery disease (CAD) among older women are reported in the literature; however, few studies adjust for demographic and health status differences. A survey assessing barriers and other factors was distributed to a stratified random sampling of older women with CAD. Factor analysis and multiple logistic regression procedures were used to estimate the impact of these issues on receiving a CAD-related office visit. The most problematic barriers included denial and low health literacy. Efforts to promote patient awareness of heart health and better communication between patients and clinicians may alleviate these barriers. 相似文献
175.
完善了商品流通现代化指标体系,并运用模糊综合法将商品流通现代化指标转换成了指数。研究发现商品流通现代化水平与其区域位置、总体经济实力密切相关,且受到产业结构的影响。同时,通过基于指数的聚类分析得到如下结论:"率先发展型区域"要抓住历史机遇,培养创新型人才,保持领先地位;"积极追赶型区域"要发挥地理优势,打破省之间、行业和部门之间、所有制之间的界限,积极参与各种区域经济合作;"流通欠发达型区域"要进一步推进和实施西部大开发战略,推进物流现代化。 相似文献
176.
K. V. Viswakala 《统计学通讯:理论与方法》2013,42(17):4367-4379
AbstractIn this paper we find the maximum likelihood estimates (MLEs) of hazard rate and mean residual life functions (MRLF) of Pareto distribution, their asymptotic non degenerate distribution, exact distribution and moments. We also discuss the uniformly minimum variance unbiased estimate (UMVUE) of hazard rate function and MRLF. Finally, two numerical examples with simulated data and real data set, are presented to illustrate the proposed estimates. 相似文献
177.
Let T2 i=z′iS?1zi, i==,…k be correlated Hotelling's T2 statistics under normality. where z=(z′i,…,z′k)′ and nS are independently distributed as Nkp((O,ρ?∑) and Wishart distribution Wp(∑, n), respectively. The purpose of this paper is to study the distribution function F(x1,…,xk) of (T2 i,…,T2 k) when n is large. First we derive an asymptotic expansion of the characteristic function of (T2 i,…,T2 k) up to the order n?2. Next we give asymptotic expansions for (T2 i,…,T2 k) in two cases (i)ρ=Ik and (ii) k=2 by inverting the expanded characteristic function up to the orders n?2 and n?1, respectively. Our results can be applied to the distribution function of max (T2 i,…,T2 k) as a special case. 相似文献
178.
宋晓英 《西南交通大学学报(社会科学版)》2011,12(3):77-81
海外华人的网络写作越来越普遍,大多以非功利的"民间"立场、"性灵性"写作特点与多元文化视角独树一帜。网名"寒胭"者写作中对家国文化传承、城市现代化进程、人性变异与现代人精神实质的追溯与揭示颇具代表性,其感伤情结、家国情怀和忧患意识体现于哀国、殇城、感人、忧世四个方面。此类写作的意义在于,当一个民族身为"弱国"的历史未过百年,被强势文化浸濡的现状尚在延续,物质的发展建构在一定道德文明代价的付出之上,而多数人已在现代化进程中麻痹自满时,作为愈是远离而乡情愈重的海外儿女,他们的民族危机意识对"人的存在"与"现代化"真正涵义的质询与考辨,无论是对于祖国民族道德传承,还是精神物质文明建构,均有着弥足轻重的镜鉴意义。 相似文献
179.
This paper concludes our comprehensive study on point estimation of model parameters of a gamma distribution from a second-order decision theoretic point of view. It should be noted that efficient estimation of gamma model parameters for samples ‘not large’ is a challenging task since the exact sampling distributions of the maximum likelihood estimators and its variants are not known. Estimation of a gamma scale parameter has received less attention from the earlier researchers compared to shape parameter estimation. What we have observed here is that improved estimation of the shape parameter does not necessarily lead to improved scale estimation if a natural moment condition (which is also the maximum likelihood restriction) is satisfied. Therefore, this work deals with the gamma scale parameter estimation as a separate new problem, not as a by-product of the shape parameter estimation, and studies several estimators in terms of second-order risk. 相似文献
180.
This paper describes the implementation of JIT in a small manufacturing company and the benefits that resulted for the company's operations. Preliminary analysis identified various problems in the existing manufacturing operations. The pre-implementation and post-implementation conditions of the company arc detailed. The achievements of the JIT implementation included a reduction in material traversing, reduced lead limes and inventories leading to an overall reduction in the cost of manufacturing. A smooth flow of material from the raw material stage to the finished product stage was established. Three separate product lines were combined into a flexible manufacturing assembly line. With the adoption of a holistic approach to JIT implementation, it was found that even a small company can make significant strides towards world class manufacturing status. The experience gained by the company can encourage and benefit other small companies to embrace the JIT approach. 相似文献