活动重叠模式与资源约束下的项目调度优化

采取活动重叠模式通常是加速研发的有效手段,带有活动重叠的资源受限项目调度问题是经典资源受限项目调度问题的扩展.首先,深入分析了活动重叠对于项目调度的影响,对活动重叠及其不确定进行详细描述与建模,提出了活动重叠导致下游活动返工时间的二项分布概率模型;其次,构建了以最小化研发项目期望工期为目标的优化调度模型,设计了基于串行进度生成机制的遗传算法对大规模问题进行优化求解;最后,基于PSPLIB J60问题库中480个算例分析了该算法的计算结果,并考察了网络参数、资源参数和重叠参数变化时,采用活动重叠模式对缩短项目工期的影响.研究结果表明:活动对资源的需求强度越小或资源稀缺程度越低,可重叠活动对数量就会增加,项目工期缩短得越明显;网络复杂度的变化对缩短项目工期的影响不大;项目中重叠活动对越多,重叠导致的下游活动返工的概率越小,项目工期缩短的越明显.     

Evolution of product quality in European,Japanese and US automotive firms: An exploratory longitudinal analysis

For years we have been hearing that US automobile manufacturers have been losing market share to their Japanese rivals who are reputed to make better quality vehicles. Most such reports are based on the initial quality surveys on new automobiles. In this paper we address two exploratory questions: (1) how does the quality of an automobile change with its age, and, (2) can firm level variables help explain differences quality. To answer these questions, we collected Consumer Reports’ reliability ratings on approximately 300 automobile models made by European, Japanese and US automotive firms during the 1998–2007; and approximately 240 models made by these firms over period of 2008–2015. For both periods we found that not only do automobiles made by Japanese firms have higher initial quality, but, as automobiles get older the difference in the product quality between Japanese versus European and US firms increases. We also found that the more generalist a European or US automobile firm, i.e., the wider is the firm׳s product offering in the marketplace, the lower its overall automobile quality during the 1998–2007 period. Conversely, Japanese generalist firms were found to have higher quality than specialist firms over the same period. The result is partly explained by the fact that Japanese firms have taken a different path to broadening their product variety – they have ensured a high level of quality of their initial offerings before entering newer market segments. The rate of reliability decline was found to be slower for all firms, and the differences in reliability across the 3 groups of firms were much less pronounced during the 2008–2015 period. This improvement may be as result of restructuring done by US automobile firms.     

Coalition-building and the forging of solidarity across difference and inequality

Diverse coalitions hold great potential for social movements, but they also face tremendous challenges. In this article, I review the literature on diverse alliances with a focus on how trust, commitment, and ultimately, solidarity can be developed and sustained across divides. The article begins by discussing the needs of diverse alliances to build trust and commitment, and the coalitional characteristics deemed vital for doing so, with a focus on shared neutral space, ongoing interaction, and social ties and bridgebuilders. Five coalitional processes and practices are identified and discussed that have been empirically found or theorized to be imperative for cultivating solidarity across difference and inequality. These processes include (a) uniting around shared principles while engaging difference; (b) acknowledging and managing inequalities; (c) making space for each other; (d) attention to managing conflicts; and (e) actions that confirm the shared commitments and negotiated identity. I conclude by evaluating the state of research on developing and sustaining alliances across divides.     

全过程跟踪审计在高校新校区建设工程项目中的实施

开展高校新校区建设工程项目全过程跟踪审计,是以一整套法律法规为准绳和依据,遵照审计规范和原则,按照审计工作计划,采用合适的审计方式,分步有序地对工程建设项目的全过程进行监督评价,以期有效地控制工程造价,提高资金使用效益,促进学校建设工程目标的实现。     

Life Course Status and Exchanges of Support Between Young Adults and Parents

The authors investigated intergenerational support exchanges in relation to young adults' life course status. In a sample of 2,022 young adults (ages 18–34 years) in The Netherlands, single young adults reported receiving more advice from parents than married young adults, and those with children of their own received more practical support. Married young adults and young adults with children provided less support to parents than, respectively, single young adults and young adults without children. Congruent with the life course perspective, the authors' findings suggest that the intergenerational support network is both durable and flexible, responding to the resources and needs associated with an individual's life course status.     

体育院校体育文化教育工程建设探究

体育院校要把校园体育文化作为一项教育工程来建设.以“一个文化内核、四种文化形态、六个文化系列”为建设思路来统领校园体育文化教育工程建设,形成一个校园体育文化体系,实现一个校园体育文化育人的优良环境,打造一个校园文化品牌,以提升学校的文化品味,增强办学特色.     

Math-oriented fields of study and the race gap in graduation likelihoods at elite colleges

This study examines the relationship between chosen field of study and the race gap in college completion among students at elite colleges. Fields of study are characterized by varying institutional arrangements, which impact the academic performance of students in higher education. If the effect of fields on graduation likelihoods is unequal across racial groups, then this may account for part of the overall race gap in college completion. Results from a large sample of students attending elite colleges confirm that fields of study influence the graduation likelihoods of all students, above and beyond factors such as students’ academic and social backgrounds. This effect, however, is asymmetrical: relative to white students, the negative effect of the institutional arrangements of math-oriented fields on graduation likelihood is greater for black students. Therefore, the race gap is larger within math-oriented fields than in other fields, which contributes to the overall race gap in graduation likelihoods at these selective colleges. These results indicate that a nontrivial share of the race gap in college completion is generated after matriculation, by the environments that students encounter in college. Consequently, policy interventions that target field of study environments can substantially mitigate racial disparities in college graduation rates.     

商业网站项目实战课程模式改革初探

本文依据高等职业教育的教学改革理念及国外课堂教学改革的经验借鉴，以信息技术专业教学为例，探讨高职工科课程教学模式改革思路。高等职业教育的宗旨是以综合职业能力培养为核心和促进人的全面发展，依托此目标高职教育课程模式的实践探索对于高等职业教育IT类课程模式的改革和发展具有重要的意义。     

Adaptive phase I/II clinical trials for drug combination assessment in oncology using the outcomes of each cycle

Many new anticancer agents can be combined with existing drugs, as combining a number of drugs may be expected to have a better therapeutic effect than monotherapy owing to synergistic effects. Furthermore, to drive drug development and to reduce the associated cost, there has been a growing tendency to combine these as phase I/II trials. With respect to phase I/II oncology trials for the assessment of dose combinations, in the existing methodologies in which efficacy based on tumor response and safety based on toxicity are modeled as binary outcomes, it is not possible to enroll and treat the next cohort of patients unless the best overall response has been determined in the current cohort. Thus, the trial duration might be potentially extended to an unacceptable degree. In this study, we proposed a method that randomizes the next cohort of patients in the phase II part to the dose combination based on the estimated response rate using all the available observed data upon determination of the overall response in the current cohort. We compared the proposed method to the existing method using simulation studies. These demonstrated that the percentage of optimal dose combinations selected in the proposed method is not less than that in the existing method and that the trial duration in the proposed method is shortened compared to that in the existing method. The proposed method meets both ethical and financial requirements, and we believe it has the potential to contribute to expedite drug development.