城市立交桥下空间的利用与设计

分析了立交桥下空间利用现状,针对桥下空间形态、桥墩形态的特征及功能利用取向,从公共性与适宜性结合、个性化与人性化结合、连续性与整体性结合、艺术性与生态性结合、安全性与适度性结合等六个方面,探讨了桥下空间的利用及设计原则。认为立交桥下的空间环境是一种宝贵的人工环境,应科学地利用这一环境,应从城市设计的角度对立交桥进行综合性的艺术设计。     

Profit‐sharing plans and affective commitment: Does the context matter?

This article analyzes the relationship between profit‐sharing plans (PSP) and affective commitment and how it is affected by the context of the PSP application. Overall, there is a positive relationship between profit sharing and commitment that is strongest in very small firms. The efficacy of a PSP in improving employees' affective commitment appears to be greatest in firms with low job‐related employee participation. Its application in workplaces where employees enjoy high levels of participation appears to have little impact and may even result in slight declines in affective commitment. © 2009 Wiley Periodicals, Inc.     

Encouraging knowledge sharing among employees: How job design matters

Job design is one of the most frequently researched practices in the Human Resource Management (HRM) literature, and knowledge sharing has become an important and heavily researched managerial practice. The links between these practices, however, have received little attention in the literature. We argue that job design matters to knowledge sharing for motivational reasons. Specifically, jobs contain characteristics that stimulate different kinds of motivation toward knowledge sharing, which have different effects on individual knowledge sharing behavior. We develop six hypotheses that unfold these ideas and test them on the basis of individual‐level data collected within a single firm. The hypotheses are tested in a LISREL model that confirms that job characteristics, such as autonomy, task identity, and feedback, determine different motivations to share knowledge, which in turn predict employees' knowledge sharing behaviors. © 2009 Wiley Periodicals, Inc.     

Reliable design of a congested disaster relief network: A two-stage stochastic-robust optimization approach

The preparedness of humanitarian relief networks can be enhanced by pre-positioning resources in strategic locations and using them when disasters strike, a strategy that gives rise to a two-stage planning problem. This paper presents a novel two-stage stochastic-robust optimization approach for integrated planning of pre- and post-disaster positioning and allocation of relief resources, while taking into consideration the uncertainty about demand for relief services and disruptions in the relief facilities and the transportation network. The proposed approach enables planners to effectively use limited historical data and imperfect experts’ opinions to obtain robust solutions while avoiding the over-conservatism of classical robust optimization methods. The objective sought is to minimize the expected total time victims need to receive assistance, including both access time to facilities and waiting/service time in them. Congestion in relief facilities is accounted for by modeling them as queuing systems and penalizing waiting time. A decomposition method based on column-and-constraint generation is implemented to solve the problem, whereas the nonlinear terms corresponding to queuing in the second-stage problem are handled using a direct search procedure. Applicability of the proposed approach is demonstrated through a real case study and the numerical results are analyzed to draw managerial insights.     

Time-varying road network design for urban hazmat transportation

Hazmat transportation in cities faces significant risks that may cause catastrophic losses to humans. From the perspective of the regulator, the main responsibility is to mitigate hazmat transport risk by determining the availability of road networks to hazmat carriers. Based on the time-variant population distribution, the hazmat transport risk was assessed via the total population exposure associated with the resident and variable populations at different times. We propose a risk-minimizing urban hazmat road network design model for multiple types of hazmats, considering time-varying traffic. The model was applied to a realistic case study of hazmat transportation in a densely populated urban area with complex traffic in Shanghai, China.     

基于温差发电的混合动力自行车的研究

本文主要研究了一种基于温差发电的混合动力自行车,并就其改装和发动机尾气余热利用的系统优化设计进行了集中分析,最终得出了相关结论。     

表上作业法和Matlab求解土方调配方案的比较

论述了表上作业法和以线性规划理论为基础的Matlab软件求解土方调配方案两种方法,通过具体事例分析,用Matlab软件求解的调配方案跟用表上作业法求得的土方调配方案是一样的,但用Matlab软件确定土方调配方案不仅速度快而且运算结果也比较精确。合理的确定土方调配方案可以缩短工期、降低成本,提高建设项目的经济效益。     

富水粉细砂地层隧道综合降水设计与施工技术

本文通过对实例进行分析论述,解决了围岩受施工扰动和水长期浸润后开挖时不稳定问题,保证了隧道结构和施工安全,为同等或类似地质条件下的地下工程研究及施工提供借鉴和参考。     

以煤为原料的甲醇制备工艺研究

本文对以煤为原料的甲醇制备工艺研究,有利于指导煤制甲醇生产工艺实践,有助于煤制甲醇生产工艺的改进和提高。