Optimal scheduling replacement policies for a system with multiple random works

From the economical viewpoint in reliability theory, this paper addresses a scheduling replacement problem for a single operating system which works at random times for multiple jobs. The system is subject to stochastic failure which results the imperfect maintenance activity based on some random failure mechanism: minimal repair due to type-I (repairable) failure, or corrective replacement due to type-II (non-repairable) failure. Three scheduling models for the system with multiple jobs are considered: a single work, N tandem works, and N parallel works. To control the deterioration process, the preventive replacement is planned to undergo at a scheduling time T or the job's completion time of for each model. The objective is to determine the optimal scheduling parameters (T^* or N^*) that minimizes the mean cost rate function in a finite time horizon for each model. A numerical example is provided to illustrate the proposed analytical model. Because the framework and analysis are general, the proposed models extend several existing results.     

Delay causes analysis in complex construction projects: a Semantic Network Analysis approach

Delays are among the most crucial adversaries to the success and performance of construction projects, making delay analysis and management a critical task for project managers. This task will be highly complicated in large-scale projects such as construction, which usually consist of a complex network of heterogeneous entities in continuous interaction. Traditional approaches and methods for the analysis of delays and their causes have been criticised for their ability to handle complex projects, and for considering the interrelationships between delay causes. Addressing this gap, this research introduces an alternative approach for delay causes analysis by adopting Semantic Network Analysis (SNA) method. The paper reports the results from an investigation of delays in construction projects in the Oil-Gas-Petrochemical sector using SNA. The method’s capacity to identify and rank delay causes, which can assist managers in selecting appropriate measures for eliminating them, are empirically examined and discussed. The paper argues that SNA leads to a more comprehensive understanding of the main causes of delay in large and complex projects, allowing a better identification and mapping of the interrelationships between these discrete factors.     

策略延迟下众筹项目的定价和激励决策

本文研究了投资者的策略延迟行为对众筹项目的定价以及激励决策的影响。策略延迟是指投资者在投资过程中自动按照估值在相应阶段投资,并且部分投资者会刻意延迟投资来搭便车的行为。本文采用了一个两阶段模型来刻画投资者的投资行为,并进一步对比序列到来模式（投资者没有策略延迟）与同时到来模式（投资者有策略延迟）中的贝叶斯均衡。研究结果表明,当发起人采用价格激励的方式提高成功率时,投资者的策略延迟行为可能会影响最优的激励策略。当存在固定目标约束时,如果投资者没有策略延迟行为,发起人应该激励前期投资者,通过弥补他们等待成本的方式提高成功率;反之如果投资者出现策略延迟行为,对项目估值较高的投资者会自动在前期投资并且愿意承受更高的价格,此时发起人应该反过来激励后期投资者。当不存在目标约束时,不论投资者是否有策略延迟行为,发起人都应该始终激励前期投资者以获得更高的成功率以及期望收益。     

President Barack Obama's image repair on HealthCare.gov

Obama's health care initiative HealthCare.gov went live on October 1, 2013. It was plagued with problems. Furthermore, the President promised that if people liked their current health care plan, they could keep it. People were shocked when they started to receive cancelation notices from their insurance companies. Republicans seized on the opportunity to savage the president, his administration, and his health care program. Obama's approval rating was anemic and on November 7, he was interviewed by Chuck Todd and on November 14, 2013, Obama held a press conference to try to mend his image. His defense relied heavily on mortification, corrective action, and minimization but also contained instances of defeasibility, bolstering, and transcendence. This essay uses Image Repair theory to analyze and evaluate the President's image repair effort.     

数字多声束形成技术

医用超声诊断设备中存在两种声束形成技术。近年来在少数几个高档设备中使用了数字声束形成技术。正交分解是获得复包络信号的幅度和相位的关键，而数字延迟是数字电子聚焦所必须的。文中介绍了数字多声束形成的原理及应用。     

交易延迟与机构投资者交易策略研究

对于机构投资者而言,出清具有一定规模的证券时,其提交指令的行为将对证券价格造成冲击形成交易成本,之后指令执行延迟也造成交易成本。文章以既定风险厌恶的机构投资者为研究对象,探讨其在交易延迟下的最优指令提交策略。经研究表明:交易延迟下最优指令提交策略受风险态度、证券收益、证券价格的波动性、市场的流动性与深度以及瞬时冲击程度等参数影响,不同市场的情况要求机构投资者调整策略,改变指令提交过程。     

Increasing Vocal Variability in Children with Autism Using a Lag Schedule of Reinforcement

Variability has been demonstrated to be an operant dimension of behavior (Neuringer, 2002; Page & Neuringer, 1985). Recently, lag schedules have been used to demonstrate operant variability of verbal behavior in persons with a diagnosis of autism (e.g., Lee, McComas, & Jawor, 2002). The current study evaluated the effects of a Lag 1 schedule on the vocal variability of 2 nonverbal children with a diagnosis of autism. Results showed systematic increases in variability during the Lag 1 schedule. Implications of lag schedules for speech and language training are discussed.     

Former Minister Zhang's discourse on SARS: Government's image restoration or destruction?

This study analyzes the image repair discourse by Chinese Health Minister Zhang Wenkang's discourse on SARS. The minister faced several accusations: the SARS outbreak was growing, the Chinese government had covered up the severity of this problem, the Chinese government ignored Taiwanese who suffered from SARS, and the Health Ministry provided information that was neither timely nor accurate. He employed several image repair strategies (denial, defeasibility, bolstering, minimization, differentiation, attack accuser, and corrective action). However, his messages were contradictory and apparently related on false information, so his efforts were unsuccessful and he was stripped of his office.     

Surveillance of the interaction parameter of the ising model

Surveillance to detect changes of spatial patterns is of interest in many areas such as environmental control and regional analysis. Here the interaction parameter of the Ising model, is considered. A minimal sufficient statistic and its asymptotic distribution are used. It is demonstrated that the convergence to normal, distribution is rapid. The main result is that when the lattice is large, all approximations are better in several respects. It is shown that, for large lattice sizes, earlier results on surveillance of a normally distributed random variable can be used in cases of most interest. The expected delay of alarm at a fixed level of false alarm probability is examined for some examples.     

The European delay in transition to parenthood: the Italian case

A delay in the transition to parenthood is common to all European countries, but Mediterranean and North European young people follow different pathways of transition to adulthood, which are described in the article. Since 2003, we have conducted four social inquiries in Italian urban contexts involving male and female young people with and without children and the article is therefore focused on Italy. The principal purpose of this research programme is to interpret the determinants of the Italian phenomenon of delaying the birth of the first child. The interpretative axes for conceptualizing the problem are intergender and intergenerational comparisons. In particular, the results of these inquiries indicate that in Italy the delay of the parenthood transition is linked to the policy-makers' ‘delay’ in realizing that the decision to postpone having children is not strongly linked to any ‘crisis of family values’. The real problem is that since the beginning of the twentieth century, the present younger generation is the first to suffer from a general decrease in social opportunities as compared with the previous one. The mechanism is illustrated by Bourdieu: the new generation's members continue to form their life expectations on the basis of their parents' situations without considering the changes in conditions (e.g. inflation of study titles) that restrict their access to social resources. According to our results, the delay in the assumption of the parental role is an unintentional effect of a set of intentional actions aimed at creating and consolidating life conditions supporting self-realization. ‘Delayers’ continually try to resist the distressing sensations of precariousness, instability, vulnerability and uncertainty recognized by influential sociologists as distinctive features of contemporary life. Consequently, the delay in the family-building process takes on an active connotation: the attempt is to fill the gap in life chances related to gender and generational memberships. The last part of the article is dedicated to a comparison of European countries' social policies in support of parenthood.