城市家庭日常活动—出行交互制约机制研究

家庭内部的交互制约机制是解读个体活动—出行决策行为的重要视角.本文关注城市家庭多个成员间活动出行的互动关系,引入时间地理学制约观,认为家庭活动决策是"多人、多活动"交互制约下的决策行为,提出个人"活动制约度"和家庭"活动制约位"概念来描述家庭活动决策,并基于出行日志构建结构方程模型,侧重分析家庭成员间活动出行互动机理.结果表明,成员间的交互制约不仅影响个体活动出行选择,还会在个体之间相互传递并扩散到家庭活动模式上.家庭内部通过替代、互助等协作形式动态地平衡成员间的制约程度,最终确定出总体制约度最小的家庭活动出行模式.     

粉煤灰的活性效应在水泥混凝土中的应用

介绍粉煤灰的化学成分和物理性能,粉煤灰对水泥混凝土强度的作用以及经济效益。     

基于UML工作流模型的应用研究

分析了工作流模型的组成,根据统一建模语言的特点,形式化定义了为工作流过程建模的UML活动图结构以及建模规则,给出一个应用实例来描述建模过程并对模型作了详细分析。     

An analysis of the social context of children’s weekend discretionary activity participation

This paper examines the discretionary time-use of children, including the social context of children’s participations. Specifically, the paper examines participation and time investment in in-home leisure as well as five different types of out-of-home discretionary activities: (1) shopping, (2) social, (3) meals, (4) passive recreation (i.e., physically inactive recreation, such as going to the movies or a concert), and (5) active recreation (i.e., physically active recreation, such as playing tennis or running). The social context of children’s activity participation is also examined by focusing on the accompanying individuals in children’s activity engagement. The accompanying arrangement is classified into one of six categories: (1) alone, (2) with mother and no one else, (3) with father and no one else, (4) with both mother and father, and no one else, (5) with other individuals, but no parents, and (6) with other individuals and one or both parents. The utility-theoretic Multiple Discrete-Continuous Extreme Value (MDCEV) is employed to model time-use in one or more activity purpose–company type combinations. The data used in the analysis is drawn from the 2002 Child Development Supplement (CDS) to the U.S. Panel Study Income Dynamics (PSID). The results from the model can be used to examine the time-use choices of children, as well as to assess the potential impacts of urban and societal policies on children’s activity participation and time-use decisions. Our findings also emphasize the need to collect, in future travel surveys, more extensive and higher quality data capturing the intra- and inter-household interactions between individuals (including children). To our knowledge, the research in this paper is the first transportation-related study to rigorously and comprehensively analyze the social dimension of children’s activity participation.

完整街道视角下的城市道路功能分析

基于完整街道的理念,将城市道路的功能归纳为交通功能、公共活动功能和通道走廊功能三类。根据城市道路的服务对象和服务特征,将城市道路的交通功能分为快速交通功能、慢速交通功能、慢行交通功能和公共交通功能;城市道路的公共活动功能分为各类商业、社交、休憩休闲、运动等公共活动服务;城市道路作为城市中的带状构筑物,可以作为各类市政基础设施敷设的通道走廊。提出城市道路的功能是复合的,各项功能应合理组合,以充分发挥城市道路的作用。