基于QT Quick的消息分发模型研究

QT Quick是一项新技术,用于动态设计和描述图形用户界面。文章基于QT Quick技术,提出了一种消息分发模型,并结合工程实际应用,对该模型实现的关键技术、消息分发流程进行了研究。     

站台有柱雨棚结构抗震性能化设计分析

通过对铁路站台有柱雨棚"Y"形钢筋混凝土结构典型单元的抗震全过程分析,证明其按《建筑抗震设计规范》"两阶段设计"难以满足"三性能水准"的设防目标,调整结构侧向刚度来实现满足抗震性能化设计的"两阶段设计"。既便于结构设计,又能保证结构在中震下的可修复性和罕遇地震作用下的安全性。     

基于BIM的城市轨道交通运维模型交付标准研究

结合我国城市轨道交通建设的发展现状，并基于BIM（building information modeling，建筑信息模型）技术的应用尝试与实践，阐述轨道交通交付信息标准化的重要性，提出了轨道交通设施设备BIM模型数据库的初步架构。以轨道交通运营维护管理需求为导向，调研分析轨道交通交付的设施设备对象及其信息，在21类轨道交通设施设备中确定了15类交付对象，并将交付对象的属性信息分为两大模块，即基本模块和外部链接模块，规范BIM模型建制单位提交的BIM模型成果内容。最后，探讨轨道交通建筑信息模型的交付形式，对BIM模型交付的数据格式、模型拆分与组合给出了一定的建议。     

Logistics impacts of student online shopping – Evaluating delivery consolidation to halls of residence

Growth in online shopping has led to increased numbers of small delivery vehicles in urban areas leading to a range of negative externalities. Young people are significant generators of home deliveries and, when clustered in university halls of residence, can generate considerable freight traffic to one location. This paper explores the potential to consolidate these deliveries using an urban consolidation centre. Based on the case of Southampton, UK, data were compiled from three linked sources: a delivery audit of four halls of residence at the University of Southampton housing 5050 residents; annual package receipt records from Southampton Solent University halls (2294 residents); and an online shopping survey distributed to Southampton University students (486 responses). The results suggest that in cities with multiple higher education institutions (HEIs), where in excess of 8000 students live in halls, over 13,000 courier trips could be generated annually, delivering over 4000 m³ of packages. These could be consolidated onto fewer than 300 vehicles for an annual service cost of approximately £18 per student, reducing congestion, parking infringements and improving air quality. Analysis indicated student acceptance of a consolidated parcel service but operational challenges would include enforcement, performance risk, finance and delivery speed.     

标准明挖地铁车站结构内力及造价分析

不同站台宽度、柱网形式对地铁车站土建造价有重大影响。选取典型的地铁车站形式,对其结构内力及造价进行对比分析;对不同站台宽度的单柱及双柱车站内力分析其弯矩规律,并对比分析不同柱网形式下车站的弯矩变化规律。根据对比分析,11 m站台宽度的单柱车站及双柱车站的结构内力较合理,造价较低。对比分析的结论可为地铁车站方案决策提供参考。     

基于WebGIS的ITS共用信息平台信息发布系统设计

以广州市ITS共用信息平台网站发布系统的设计为背景,分析交通信息发布的需求特点,研究WebGIS技术在交通信息发布中的具体应用方法,以满足ITS共用信息平台大范围发布交通地理信息的需求。根据对外和对内交通信息发布的特点,分别提出采用胖客户机和瘦客户机模式的系统逻辑结构方案,以及使用分布式服务器组分担负载并考虑到系统安全性的物理结构方案,并对其具体实现方式进行研究。     

Can agents measure up? A comparative study of an agent-based and on-line optimization approach for a drayage problem with uncertainty

Experiments studying the behavior of agent-based methods over varying levels of uncertainty in comparison to traditional optimization methods are generally absent from the literature. In this paper we apply two structurally distinct solution approaches, an on-line optimization and an agent-based approach, to a drayage problem with time windows under two types of uncertainty. Both solution approaches are able to respond to dynamic events. The on-line optimization approach utilizes a mixed integer program to obtain a feasible route at 30-s intervals. The second solution approach deploys agents that engage in auctions to satisfy their own objectives based on the information they perceive and maintain locally. Our results reveal that the agent-based system can outperform the on-line optimization when service time duration is highly uncertain. The on-line optimization approach, on the other hand, performs competitively with the agent-based system under conditions of job-arrival uncertainty. When both moderate service time and job-arrival uncertainties are combined, the agent system outperforms the on-line optimization; however, in the case of extremely high combined uncertainty, the on-line optimization outperforms the agent-based approach.     

Weekly container delivery patterns in liner shipping planning models

This paper addresses a fundamental question related to nearly all container liner shipping planning models: whether the implicit assumption of identical container delivery pattern every week is valid in a situation of identical shipping services and identical cargo demand every week. We prove that when the number of containers transported from one port to the next is formulated as a continuous variable, the resulting mathematical model with an identical container delivery pattern is equivalent to the model with general container delivery patterns which can be different in different weeks. When the number of containers transported is formulated as an integer variable, the model with an identical container delivery pattern is not equivalent to the model with general container delivery patterns. However, the difference between the optimal objective values of the two models is negligible for practical applications. In sum, little, if not nothing, is lost by assuming an identical container delivery pattern in liner shipping planning models.     

基于稳定性理论的张力腿平台横摇固有周期分析

文章以稳定性理论为基础提出了一种张力腿平台横摇固有周期计算模型,分析了横摇临界角对平台横摇稳定性的影响,并将其应用于分析平台设计参数对横摇固有周期的影响。提出在一个横摇周期里,最后稳定横摇临界角对应的时间历程为1/4横摇固有周期这一假设,基于此假设,编制计算机计算程序,计算横摇运动中每一个横摇角,判断其稳定性,找出一个横摇周期内最后稳定横摇临界角对应的时间历程,求解横摇运动固有周期。考虑两种横摇阻尼情况,计算不同初始横摇角、横摇下沉位移、张力腱长度、平台重量和横摇阻尼的横摇固有周期,论证了平台设计参数对横摇固有周期的影响。该计算模型克服了从结构角度计算固有周期工作量大、计算周期长、计算结果不可靠的弱点,使横摇固有周期计算简单、有效。通过与不考虑横摇阻尼的情况对比,分析了横摇阻尼对横摇固有周期的影响。可以快速计算处于设计阶段或者已服役张力腿平台横摇固有周期。结合一型设计中的张力腿平台,应用文中提出的横摇固有周期计算模型对该平台进行了横摇固有周期的计算,并且分析了平台参数对横摇固有周期的影响。结果表明该方法可以对张力腿平台横摇固有周期进行快速计算。并可推广应用于其它海上结构物的横摇固有周期计算。     

基于物联网技术的血液物证保全系统的设计与实现

本文利用物联网技术设计了血液物证保全系统,包括研发一款便携式智能血液物证送检箱和建立血液物证信息化保管平台。系统同时可使血液物证从提取到送检移交全过程密闭、低温冷藏保存,且可进行在线血液监管,较好的保全血液物证。系统同时可实现血液物证系统化、规范化保管,使血液检验结论更客观、公正,对规范酒驾、醉酒办案具有重要的支撑作用。