Fibonacci helps to evacuate from a convex region in a grid network

This study considers an evacuation problem where the evacuees try to escape to the boundary of an affected area, which is convex, and a grid network is embedded in the area. The boundary is unknown to the evacuees and we propose an online evacuation strategy based on the Fibonacci sequence. This strategy is proved to have a competitive ratio of 19.5, which is better than the best previously reported result of 21.     

比较优势动态递减概率模型及检验

在比较优势的持续时间是随机变量的条件下,文章运用不确定性数学方法和规范方法,推出了比较优势递减定理,认为比较优势会随着时间增加而递减,具有发散效应,即比较优势不会被锁定.推出的比较优势“无记忆性”定理表明,各国遵循比较优势发展国际贸易是正确的,国际贸易会让各个国家自动寻找到适合本国的比较优势.通过定义比较优势逆转概率,运用实证方法进行研究,研究表明比较优势基本符合比较优势递减定理和“无记忆性”定理内容,认为中国传统劳动密集型优势在逐渐减小,产业结构调整非常成功,逐渐拥有资本密集型优势和技术密集型优势,产业结构越来越合理.     

Small area estimation strategies for large population surveys: a comparison of design and model-based methods

Small area estimation (SAE) concerns with how to reliably estimate population quantities of interest when some areas or domains have very limited samples. This is an important issue in large population surveys, because the geographical areas or groups with only small samples or even no samples are often of interest to researchers and policy-makers. For example, large population health surveys, such as Behavioural Risk Factor Surveillance System and Ohio Mecaid Assessment Survey (OMAS), are regularly conducted for monitoring insurance coverage and healthcare utilization. Classic approaches usually provide accurate estimators at the state level or large geographical region level, but they fail to provide reliable estimators for many rural counties where the samples are sparse. Moreover, a systematic evaluation of the performances of the SAE methods in real-world setting is lacking in the literature. In this paper, we propose a Bayesian hierarchical model with constraints on the parameter space and show that it provides superior estimators for county-level adult uninsured rates in Ohio based on the 2012 OMAS data. Furthermore, we perform extensive simulation studies to compare our methods with a collection of common SAE strategies, including direct estimators, synthetic estimators, composite estimators, and Datta GS, Ghosh M, Steorts R, Maples J.'s [Bayesian benchmarking with applications to small area estimation. Test 2011;20(3):574–588] Bayesian hierarchical model-based estimators. To set a fair basis for comparison, we generate our simulation data with characteristics mimicking the real OMAS data, so that neither model-based nor design-based strategies use the true model specification. The estimators based on our proposed model are shown to outperform other estimators for small areas in both simulation study and real data analysis.     

“经验研究”与“理论研究”——古典社会学、心理学的诠释学意涵

当前中国社会学中的一个突出问题是,"经验研究"与"理论研究"两个阵营之间相互质疑。然而,从当代诠释学的角度则有"经验"与"理论"一致性的命题:经验是文本的类似物。这一命题原创性地蕴含在社会学和心理学的奠基者詹姆斯、涂尔干、弗洛伊德和韦伯的思想之中,而本文的主体部分即发掘这些古典思想的诠释学意涵。文章指出,基于这一诠释学命题的理论建构,在解决中国社会学中两个阵营对峙问题的同时,将文化自觉置于学科建设的基础位置。     

体制化“空转”： 发展悖境中社区工作站运行的组织行为分析——以S市X社区为例

社区工作站作为承接政府社区公共服务职能的新型社会组织，似乎并未真正摒弃行政化积弊及普遍性怠政现象，凸显出事实与价值背离的发展悖境态势。在当前新工作情境下，社区工作站无论是窗口、街头还是社区,其实都呈现出无工作负荷的“空转”状态，并彰显惯习性运作的体制化印记，而体制化“空转”的致因逻辑又在于情境暗示效应下的规章制度软性约束、街道办“示范效应”及社区工作“应付法则”。对此，有必要由情境反思予以解悖，从“干净的石板（clean slate）”出发，在政策原点上破解社区工作站的运行困境，尝试社区工作站的机构撤并及职能删减,以摒除社区公共服务工作中本不该有的体制化“空转”状态，力促基层组织体制改革去行政化的不二取向。     

基于符号吸引理论的广南地母文化旅游开发

地母文化是遍布于世界各地由原始崇拜演化而来的文化现象。笔者在对我国地母文化旅游资源的调查研究过程中，将符号吸引理论运用于广南地母文化旅游区的旅游规划设计，为广南地母文化符号的旅游产品开发提供科学依据。     

对马克思主义理论整体性问题研究的反思及其现实意义

整体性是马克思主义理论的重要特性,整体性问题是研究马克思主义的一个基本问题,也是当前我国学者研究马克思主义的一个热点问题。我国理论界围绕此问题进行了深入而系统的研究,取得了丰硕成果,但也存在一些问题,对这些问题的反思,有益于进一步实现马克思主义整体发展和创新的前瞻性使命。     

浅析大学生人际信任的现状及对策

大学生人际信任是研究大学校园内人际关系的一个重要维度,是大学生进行良好人际交往的重要前提.大学生正处于由青少年时期向成年早期过渡的阶段,获得自我同一性和亲密感、建立和维持良好的人际信任关系对大学生来说是其健康发展的重要保障.本文通过对大学生人际信任现状的分析,同时辅以对人际信任概念的梳理,从而提出了增强大学生人际信任的具体措施.     

Evaluation of scheduling strategies for a dynamic job shop in a tool-shared,flexible manufacturing environment

A two-phase approach is used to examine the impact of job scheduling rules and tool selection policies for a dynamic job shop system in a tool-shared, flexible manufacturing environment. The first phase develops a generalized simulation model and analyses 'simple' job scheduling rules and tool selection policies under various operating scenarios. The results from this investigation are then used to develop and analyse various bi-criteria rules in the second phase of this study. The results show that the scheduling rules have the most significant impact on system performance, particularly at high shop load levels. Tool selection policies affect some of the performance measures, most notably, proportion of tardy jobs, to a lesser degree. Higher machine utilizations can be obtained at higher tool duplication levels but at the expense of increased tooling costs and lower tool utilization. The results also show that using different processing time distributions may have a significant impact on shop performance.