基于随机p-鲁棒优化的国家血液战略储备库选址-库存模型

以往的救灾实践对建立国家血液战略储备体系提出了迫切要求。国家血液战略储备库的建设问题亟待解决。由于血液产品特性以及应急血液保障特性的存在,使得国家血液战略储备库的选址决策具有一定的复杂性。本文将问题定位为选址-库存问题。首先,以应急条件下血液保障及时度最高为目标,构建了一个不确定环境下考虑多情景、多血型、多阶段、带提前期、有容量限制、日常随机需求、有预算约束及协同定位的国家血液战略储备库选址-库存模型。同时,为了规避应急条件下的不确定风险,进一步构建了国家血液战略储备库选址-库存问题的随机p-鲁棒优化模型。该模型为离散非线性混合整数规划模型,难以快速精确求解。故基于模型性质,设计了相应的遗传算法。最后,设计了两组算例验证模型与算法的有效性。其中,第1组算例基于我国大陆地区31个省级血液中心与省级行政区的数据,并根据不同预算值给出6个算例,得到了国家血液战略储备库的选址-库存决策方案。第2组算例为6个不同规模的模拟算例,用来测试不同规模下的算法性能。算例结果表明：遗传算法的性能更好;鲁棒解与确定性模型最优值相差不大（最大差距≤1.08%）,可降低不确定性导致的风险。实践中,可对本文所建模型稍作改进,应用于具有类似特征的易腐品（药品、粮食等）应急物资储备库选址-库存决策。     

小额信贷可持续发展面临的问题及对策分析

小额信贷引入我国已有近二十年了,对我国的扶贫攻坚计划起了重要的作用,但随着经济形势的变化,小额信贷面临一些新的问题。本文从小额信贷的产品设计、目标群体的定位、财务可持续以及面临的风险等四个方面出发,分析了其面临的可持续问题,并在此基础上提出了相关对策。     

关于普通理工科院校汉语言文学专业定位与发展的思考

汉语言文学专业是许多理工科院校开办的一个新的传统学科专业。本文就理工科院校的汉语言文学专业如何利用自身优势,改革培养模式,准确定位,办出特色,在高等教育汉语言文学专业人才市场中占有一席之地,进行研究与探索。     

西藏产业结构优化与主导产业选择

文章运用产业结构理论,对西藏产业结构所处的工业发展阶段、三次产业产值结构和就业结构的变动进行了总体评价.最后,通过科学选择西藏产业结构优化的战略导向,利用区位商方法,着重分析了西藏产业结构优化过程中的主导产业问题,由此确立了西藏工业经济应该培育和扶持的一级和二级主导产业部门.     

Evaluating the Temporal Location of Feedback: Providing Feedback Following Performance vs. Prior to Performance

In order to make feedback as effective as possible, it is important to understand its function in the three-term contingency (TTC) and the impact of various factors involved in delivering feedback. Timing of feedback is one factor that can affect the impact of feedback on learner’s behavior. An analysis of timing of feeback may help us getting closer to better understanding how feedback functions in the TTC. The purpose of this study was to evaluate the effects of feedback at different temporal locations. Specifically, feedback was provided either immediately (a) after a teaching session or (b) before the following teaching session, on teaching performance of undergraduate psychology students. The results indicated that feedback provided before the teaching session was more effective in improving teaching skills than feedback that was provided after the session. These findings suggest that feedback may function primarily as an antecedent to future performance and not necessarily as a consequence for past performance. However, the behavioral mechanism that explains these results is not yet clear. Future studies should investigate this further by manipulating the content of feedback prior to the teaching performance.     

新形势下上海引进外资问题研究

基于新形势下上海引进外资出现的新情况、新问题,通过对上海投资环境、定位和区位的具体分析,建立上海吸引高端外资的系统框架,并提出上海在市场开放方面,应扩大外资进入领域,鼓励外资投向"上海制造"、"上海服务"、"上海创造"的高端产业,依次引导外资的产业结构升级;在投资环境方面,应建立统一和可预见的法制环境,完善社会信用制度,以此维护市场的竞争秩序;在市场准入方面,应放宽行业限制,不断调整和优化利用外资结构。     

论高校国防教育的学科定位

随着教育自身的发展和国际局势的变化,高校国防教育呈现出新的时代特色和学科特点,表现为:全球性的视角、多功能的互补和多学科的渗透。高校国防教育处在众多学科的交叉点上,从共性中突出个性,从普遍性中寻找特殊性,是确立学科定位的基本原则。依照主体性原则,高校国防教育应以高校为主体;其次,国防是国防教育的出发点和落脚点,是目的和归宿,因此高校国防教育应以国防为本位;再次,任何领域的教育现象最终都要落实到育人上来,因此,育人是高校国防教育的基础。     

A test for the equality of k medians against the simple tree alternative under right censorship

We consider a test for the equality of k population medians, θ_i i=1,2,….,k, when it is believed a priori, that θ _i: The observations are subject to right censorhip. The distributions of the censoring variables for each population are assumed to be equal. This test is compared with the general k-sample test proposed by Breslow     

Geeta distribution and its properties

A new discrete distribution defined over all the positive integers and with the name of Geeta distribution is described. It is L-shaped like the logarithmic series distribution, Yule distribution and the discrete Pareto distribution but is far more versatile than them as it has two parameters. It belongs to the classes of location parameter distributions, modified power series distributions, Lagrange series distributions and exponential distributions. Its mean fi, variance a2 and two recurrence formulae for higher central moments are obtained. Convolution theorem and variations in the model with changes in the parameters have been considered. ML estimators, MVU estimators and estimators based of mean and variance and on mean and first frequency have been derived.     

On the one-sample location hypothesis for mixed bivariate data

We study a hypothesis testing problem involving the location model suggested by Olkin and Tate (1961). Specifically, we derive a likelihood ratio lest of the associated location hypothesis as an alternative to the conventional method of carrying out separate tests for each of the parameters. A small sample Monte Carlo comparison indicates the general superiority of the former in terms of statistical power. We also comment briefly on the properties of the test.