Exact and efficient Bayesian inference for multiple changepoint problems

We demonstrate how to perform direct simulation from the posterior distribution of a class of multiple changepoint models where the number of changepoints is unknown. The class of models assumes independence between the posterior distribution of the parameters associated with segments of data between successive changepoints. This approach is based on the use of recursions, and is related to work on product partition models. The computational complexity of the approach is quadratic in the number of observations, but an approximate version, which introduces negligible error, and whose computational cost is roughly linear in the number of observations, is also possible. Our approach can be useful, for example within an MCMC algorithm, even when the independence assumptions do not hold. We demonstrate our approach on coal-mining disaster data and on well-log data. Our method can cope with a range of models, and exact simulation from the posterior distribution is possible in a matter of minutes.     

INNUMERABLE TRANSMISSIONS: WI-FI® FROM SPECTACLE TO MOVEMENT

This paper analyses Wi-Fi, a mundane wireless networking technology, in terms of a cultural flow of meanings concerning movement of people and data. The principal analytical problem addressed in the paper is how to make sense of the profusion of images, practices, events, objects and social groupings associated with Wi-Fi. Rather than treating the abundance as driven by the IT industry's desire to find the Next Big Thing, or as hype that obscures actual social realities, the paper suggests that different ideas, ambivalences, frustrations and problems with Wi-Fi form part of an ongoing contestation of the meaning and value of information infrastructures. Using a model of culture drawn from Ulf Hannerz, the paper describes how meanings flow in three axes: ideas or modes of thought, forms of externalization and social distributions. Wi-Fi offers a significant opportunity to analyse how different movements of people and data are collectively negotiated and figured. The reflexive and tactical uses of wireless networks to contest ideas of information and movement are key elements of this negotiation.     

关于封建化的道路问题

本文概述了封建化道路问题的研究情况 ,并通过中西方历史对比 ,指出了中国封建化道路的特点和模式。     

文明的自性

文明总是处于生成之中,但就其本性而言,文明又总会努力守持其本原性的历史文化规定性,并以此为前提,处在一个不断自主性地扬弃旧我,又从其他文明中吸纳养分以重构新我的过程中.一个文明既不是又仍然是而且在更大程度上仍然是其先前所是的那个文明;亦即,在其自主性的发展中和与其他文明的互动中,一个有生命力的文明会努力葆守其本原性的历史文化规定性,同时又不断创造性地重构自我.     

虚拟团队关键成功因素模型构建与实证研究

在对虚拟团队相关文献深入检索与分析的基础上,归纳、提炼出影响虚拟团队成功的15项关键因素,构建了虚拟团队关键成功因素三维(目标、成员、沟通)模型假设;通过对国内12家IT企业的问卷调查,收集到242条有效数据;利用描述性统计分析对15项关键因素进行了验证,利用R型因子聚类分析对三维模型假设进行验证,结果表明15项关键成功因素体现在目标一致性、信息技术能力、成员素质、领导能力和沟通协调能力五个维度上;最后,从这五个方面出发,给出了提升虚拟团队绩效的针对性策略.     

The Future of HRD Research: A SWOT analysis by five leading scholars in the field

This article presents a review of the 11th International Conference on Human Resource Development Research and Practice across Europe through the lens of global mobility. The conference was held in Pécs, Hungary in June, 2010 and the four authors who participated in the conference present their own narratives as agents of global mobility, examine the theme of global mobility in the various aspects of the conference, and conclude with reflections on the factors that supported the learning environment at the conference.     

Frugal innovation for supply chain sustainability in SMEs: multi-method research design

Abstract

In this study, we attempt to establish the missing links between supply chain sustainability and frugal innovation. Our study motivations stem from two facets of the emerging markets: first, the institutional barriers and, second, the resource constraints. We argue that there is a synergy in the concepts of frugal innovation and sustainability in supply chains and there is a need to further explore this synergy. Furthermore, we claim that even in the wake of many success stories in the frugal innovative supply chain management practices from emerging markets such as India, there are very few, if any, attempts made to understand the implications of a sustainability oriented frugal innovations in the particular context. To address this gap, we develop a model to establish the linkage between sustainable supply chains and frugal innovations. Our proposed conceptual framework depicts the hierarchy and interlinks of the identified enablers in developing sustainability oriented frugal innovative capabilities in supply chains. Furthermore, we have empirically validated our theoretical framework using survey data. We observed that most of the interpretive links are supported. These findings extend the understanding of frugal innovation for supply chain sustainability using multi-method research design, while also providing theoretically guidance to managers in the development of frugal innovation capability to achieve sustainability in supply chain in resource constrained environment.     

Learning to learn and productivity growth: Evidence from a new car-assembly plant

This paper models learning by experience beyond the experience curve, including the possibility of “learning to learn”: the pace of learning increases over time by building on what has already been learned. We compare the extended deterministic learning model with Jovanovic and Nyarkos' [26] stochastic learning. The theoretical models are tested with data on the total factor productivity of a car-assembly plant in its first months of operation. We find that the deterministic “mixed learning model”, where the speed of learning is equal to a constant plus a learning to learn effect, is the one that best fits the empirical data. The mixed learning model results in a time pattern of total factor productivity growth, first increasing and later decreasing, different from the always decreasing rate of growth of the learning curve, opening new perspectives on the study of learning by experience.     

圆柱壳开孔补强结构的有限元分析

使用ANSYS软件计算同一筒径,不同开孔直径壳体,共六个模型的应力集中系数.按等面积补强法计算出以上模型分别采用补强圈补强和厚壁接管补强各自的厚度,建立相应的模型,求出应力集中系数.有限元的分析方法可以证明:在局部区域内产生较大的塑性变形时采用补强圈或厚壁接管补强,均可有效的改善孔边的应力集中,相同壳体直径,开相同大小的孔时,接管补强后的应力集中系数小于补强圈补强的应力集中系数.     

我国国债市场主要问题及其完善对策

1998年以来,我国国债市场得到了迅速的发展,但是,在拉动经济增长的同时其自身的问题也日渐突出,市场化程度不高,流动性较差,相对分裂的格局制约着整个市场的快速、良性发展。基于如此状况,建立一个统一的、多层次的、面向所有金融机构、企业法人和个人投资者的国债市场已成为市场完善的主导方向。