Reliability analysis of load-sharing systems with memory

The load-sharing model has been studied since the early 1940s to account for the stochastic dependence of components in a parallel system. It assumes that, as components fail one by one, the total workload applied to the system is shared by the remaining components and thus affects their performance. Such dependent systems have been studied in many engineering applications which include but are not limited to fiber composites, manufacturing, power plants, workload analysis of computing, software and hardware reliability, etc. Many statistical models have been proposed to analyze the impact of each redistribution of the workload; i.e., the changes on the hazard rate of each remaining component. However, they do not consider how long a surviving component has worked for prior to the redistribution. We name such load-sharing models as memoryless. To remedy this potential limitation, we propose a general framework for load-sharing models that account for the work history. Through simulation studies, we show that an inappropriate use of the memoryless assumption could lead to inaccurate inference on the impact of redistribution. Further, a real-data example of plasma display devices is analyzed to illustrate our methods.

     

施工企业投标优化的问题与对策

通过对某大型施工企业多个铁路、公路施工项目部的调查，总结了企业当前投标优化方面存在的问题。针对企业以铁路、公路项目为主业的特点，提出了优势项目滚动发展、建立有效激励制度、做好投标准备、优化施工组织设计、应用报价技巧等优化对策。对于施工企业改善市场经营效果，提高中标质量，增加项目盈利有重要的借鉴作用。     

Internal consistency of demographic assumptions in the shared socioeconomic pathways

A new set of alternative socioeconomic scenarios for climate change researches—the shared socioeconomic pathways (SSPs)—includes for the first time a more comprehensive set of demographic conditions on population, urbanization, and education as the central scenario elements, along with other aspects of society, in order to facilitate better analyses of challenges to climate change mitigation and adaptation. However, it also raises a new question about the internal consistency of assumptions on different demographic and economic trends under each SSP. This paper examines whether the interactions between the demographic and economic factors implied by the assumptions in the SSP projections are consistent with the research literature, and whether they are consistently represented in the projection results. Our analysis shows that the interactions implied by the demographic assumptions in the SSPs are generally consistent with findings from the literature, and the majority of the assumed relationships are also evident in the projected trends. It also reveals some inconsistency issues, resulting mainly from the use of inconsistent definitions of regions and limitations in our understanding of future changes in the patterns of interactions at different stages of socioeconomic development. Finally, we offer recommendations on how to improve demographic assumptions in the extended SSPs, and how to use the projections of SSP central elements in climate change research.     

Diagnostics for quasi-likelihood nonlinear models

Quasi-likelihood nonlinear models (QLNMs) are an extension of generalized linear model and include a widen class of models as special cases. This article investigates some diagnostic methods in QLNMs. An equivalency between a case-deletion model and a mean-shift outlier model in QLNM is established. Two simulation study and a real dataset are used to illustrate the proposed diagnostic methods.     

"三不朽"图赞与"速朽"《阿Q正传》的文脉勾连

张岱晚年所著《於越有明三不朽图赞》,以图像加赞辞的形式,辑录了绍兴有明一代先贤的事迹,汇成人物传记式圣贤画谱.鲁迅家藏该著作珍本,曾于1912、1913年两次补绘插图,补足跋语,周建人抄录赞文,鲁迅又两次购藏此书三册,以表达对绍兴先贤和文学前辈的敬意.本文是学界首次整理鲁迅补录手迹,赏析鲁迅唯一存世手绘圣贤人物画像,基于"三不朽"的儒教内涵,赞文体裁的文学性,鲁迅对张岱文章史著风格的传承,勾连"反圣贤"的白话小说《阿Q正传》,于此个案回溯流转的文脉深处,论证所谓"沉默期"鲁迅钞校古籍与新文学创作之间的对话关系.     

Composite quantile regression for massive datasets

Analysis of massive datasets is challenging owing to limitations of computer primary memory. Composite quantile regression (CQR) is a robust and efficient estimation method. In this paper, we extend CQR to massive datasets and propose a divide-and-conquer CQR method. The basic idea is to split the entire dataset into several blocks, applying the CQR method for data in each block, and finally combining these regression results via weighted average. The proposed approach significantly reduces the required amount of primary memory, and the resulting estimate will be as efficient as if the entire data set is analysed simultaneously. Moreover, to improve the efficiency of CQR, we propose a weighted CQR estimation approach. To achieve sparsity with high-dimensional covariates, we develop a variable selection procedure to select significant parametric components and prove the method possessing the oracle property. Both simulations and data analysis are conducted to illustrate the finite sample performance of the proposed methods.     

大学生海岛户外体育拓展基地模式的构建——以江苏省海州湾地区为例

江苏省海州湾地区海岛资源丰富,优势明显,十分适合于海岛户外体育拓展.研究了该地区海岛体育资源特点和现状,分析了在海州湾地区构建大学生海岛户外体育拓展基地的优势,在此基础上,提出了构建大学生海岛户外体育拓展基地的模式选择.     

网络环境下服务科学与创新管理研究展望

基于网络环境的服务发展与创新已成为经济发展的新引擎。本文在分析网络环境下服务特征基础上，探讨了其对服务科学与创新管理研究的影响。结合我国社会经济发展对现代服务快速增长的需求，本文提炼了服务科学研究的三类基本科学问题，包括服务价值的内涵与度量，服务资源的要素及其价值生成，和服务关系的界定与形成问题；提出了服务与创新管理的四个重要研究领域，即：服务生态系统的形成与演化，服务资源要素的组织与协调，服务的关联与融合和社会服务运作管理问题。在四个重要研究领域的进一步分析中，论文以一个异质数据服务资源的组织与融合为例，描述了服务资源组织与协调的一个具体问题，说明了已有研究方法解决该问题的困难，和未来该问题研究需要关注的重点；另以平台服务中基于价值和关系的服务定价问题为例，说明服务关联与融合研究的挑战及其未来研究的努力方向。     

人工智能时代的话语悖论与结构转向

以追求智能、精准为核心的技术认知对突发社会问题的预测失灵,形塑了人工智能时代的话语悖论。此悖论体现出盲目崇尚加速的、闭合化的现代性认知结构的困窘,且揭示了晚近技术反思的谱系化与经验"二分"的双重结构观的局限性,进而使超越悖论的结构转向成为必须面对的命题。因此关键在于以突发社会问题为节点,面向日常生活,实现对"二分"的总体性统合。唯有把握日常生活在突发问题中可能产生的反转契机,合理审视智能化的技术,促使技术的精准思维融入于日常生活之中,方能为加速多变的现代科学创设总体化的良善格局。     

日本“向右转”的民族两面性解读——读《菊与刀》的文化启示

近期,日本社会右倾化抬头,日本政府对钓鱼岛的“国有化”事件引发中日关系的紧张,日本为什么会向右转,会走多远?成为牵动整个亚太格局变动的重大因素.要深刻地理解当下日本政治“向右转”的深层次原因,需要从全球、亚太地区格局变动、日本国内的困境来进行考察,更重要的是要对日本的传统文化特征进行剖析.真切了解与中国利益攸关的日本的民族性,是21世纪前半叶中国在崛起过程中所必须解决的问题.本文依据美国学者撰写的报告《菊与刀》,对日本的民族性进行剖析,以期引起国内思想界和学术界的重视.