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61.
Wang  Dewei  Jiang  Chendi  Park  Chanseok 《Lifetime data analysis》2019,25(2):341-360

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.

  相似文献   
62.
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。  相似文献   
63.
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.  相似文献   
64.
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.  相似文献   
65.
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.  相似文献   
66.
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.  相似文献   
67.
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.  相似文献   
68.
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。  相似文献   
69.
当前,农村地区彝族青年的婚姻困境问题明显,形式变异的"买卖婚"在强大的社会心理支撑下普遍存在,婚姻困境中的性别差异明显,青年男女的婚姻自由受到限制,固守传统婚姻形式造成多种社会问题。破解农村地区彝族青年婚姻困境,需要给予公共政策支持的外力推动,形成解决这一问题的内生动力,并最终帮助彝族青年男女突破婚恋的物质和精神束缚,促进农村地区婚姻进步和经济社会发展。  相似文献   
70.
通过对青岛市儿童文学翻译市场进行调查研究,在对《爱丽丝漫游奇境记》的大量复译本进行分析的基础上,我们发现,众多儿童文学经典复译作品在秉承初译优点、取得不同程度进步的同时,也暴露出一些问题,比较普遍的是漏译、误译和文字中英夹杂、有失规范等问题,最关键的问题在于儿童文学翻译的文学性没有质的提高,没有从根本上超越初译。我们认为,儿童文学的复译应该遵循批判性借鉴和实质性超越的原则,真正实现其存在价值。  相似文献   
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