Joint leisure travel optimization with user-generated data via perceived utility maximization

The lack of personalized solutions for managing the demand of joint leisure trips in cities in real time hinders the optimization of transportation system operations. Joint leisure activities can account for up to 60% of trips in cities and unlike fixed trips (i.e., trips to work where the arrival time and the trip destination are predefined), leisure activities offer more optimization flexibility since the activity destination and the arrival times of individuals can vary.To address this problem, a perceived utility model derived from non-traditional data such as smartphones/social media for representing users’ willingness to travel a certain distance for participating in leisure activities at different times of day is presented. Then, a stochastic annealing search method for addressing the exponential complexity optimization problem is introduced. The stochastic annealing method suggests the preferred location of a joint leisure activity and the arrival times of individuals based on the users’ preferences derived from the perceived utility model. Test-case implementations of the approach used 14-month social media data from London and showcased an increase of up to 3 times at individuals’ satisfaction while the computational complexity is reduced to almost linear time serving the real-time implementation requirements.     

船用双平衡环挠性陀螺仪接头设计准则及力学分析

本文讨论了船用双平衡环挠性陀螺仪接头的设计准则，进行了接头的刚度计算及承载能力和强度分析，从而为设计高精度挠性陀螺仪提供了重要的参考依据。     

公用移动通信铁路共建干扰及隔离度分析

公用移动通信引入铁路时将进行不同制式移动通信系统的共建共享,通过对多系统间产生干扰的机制和隔离度计算进行剖析,探讨多系统共用铁塔和漏泄电缆的建设方案。     

浅谈改性沥青及SMA路面平整度的控制

从沈大SMA表面层施工中分析影响平整度的主要因素,认为重点应从摊铺、碾压和接缝处理等施工工艺方面对平整度进行控制。     

水泥混凝土路面设计关键问题探讨

通过分析水泥混凝土路面设计过程中应注意的一些关键问题,从路面结构组成、隔离封层和缓冲封层设置、板块划分、接缝设计、钢筋网等五个方面阐述了相应的设计要点及应注意的问题.     

面向骑行者的AEB测试方法研究

文章通过对CIDAS统计的150例汽车与二轮车碰撞事故工况样本参数信息进行系统聚类分析,提取出了用于评价面向骑行者的自动紧急制动系统(AEB)的测试场景,建立了面向骑行者的自动紧急制动系统测试评价方法,并利用Prescan和Simulink软件搭建了典型场景的虚拟交通模型以及自动紧急制动系统(AEB)算法控制模型,通过联合仿真分析验证了AEB控制算法的具体实施过程,进一步说明了典型场景和测试方法的有效性。     

海上联合搜救机制研究

海上联合搜救是一项复杂的系统工程,需要建立规范科学完整的机制来推动.海上联合搜救机制的建立要符合政治、经济、技术和管理需要.目前的海上联合搜救机制存在机制内容不完整、不被重视、缺乏统一的指挥协调机构和保障机制不完善等问题建议应重视并建立规范科学完整的海上联合搜救机制,建立统一的指挥协调机构,制定相关制度规范参与方行为,建立切实有效的保障制度;通过联合来达到信息共享、技术交流、资源援助和人员支持等目的.     

关联在多表数据操作中的应用

面对大量数据,关联是一种行之有效的方法。由于VFP语言简单易学,有广大的用户群,非常适合普及。这就使得非计算机人员也可以方便的掌握关联这种方法。经过几年的应用,我们在利用用户别名来分清当前工作区、关联时索引关键字必须结构一致、多对一表的关联方法、关联产生循环的处理方法等方面总结出一些经验。     

An activity-episode generation model that captures interactions between household heads: development and empirical analysis

In this paper, we develop an approach for modeling the daily number of non-work, out-of-home activity episodes for household heads that incorporates in its framework both interactions between such members and activity setting (i.e. independent and joint activities). Trivariate ordered probit models are estimated for the heads of three household types – couple, non-worker; couple, one-worker; and couple, two-worker households – using data from a trip diary survey that was conducted in the Greater Toronto Area (GTA) during 1987. Significant interactions between household heads are found. Moreover, the nature of these interactions is shown to vary by household type implying that decision-making structures and, more generally, household dynamics also vary by household type. In terms of predictive ability, the models incorporating interactions are found to predict more accurately than models excluding interactions. The empirical findings emphasize the importance of incorporating interactions between household members in activity-based forecasting models.     

节理倾角对公路隧道围岩塌落拱影响分析

文章主要通过室内石膏块模型试验对节理间距为0.5 m的隧道围岩在节理倾角分别为0°,30°,45°,60°和90°时无支护开挖情况下围岩的塌落拱跨度、高度和塌落面积的探讨,得出了在不同节理倾角下得到的结果 ,并与普氏理论值进行了对比分析,发现塌落高度、塌落宽度以及塌落面积均与节理倾角呈非线性变化关系,其极小值介于45°~60°之间;同时利用离散元软件UEDC对上述工况进行二维数值分析,室内试验结果与数值分析结果一致;依据数值计算和室内试验综合分析,得到了在不同节理倾角下塌落拱高度的计算方法。