数据挖掘技术在物流客户关系管理中的应用

通过数据挖掘技术的引入,提出了一种新的物流客户关系管理方法。在对数据挖掘方法作了全面论述的基础上,着重分析了关联分析方法和决策树分析方法,并结合两个实例讨论了方法的应用。     

Capacity-constrained traffic forecasting model

Projecting future traffic is an important stage in any traffic and transportation planning study. Accurate traffic forecasting is vital for transportation planning, highway safety evaluation, traffic operations analysis, and geometric and pavement design among others. In view of its importance, this paper introduces a regression-based traffic forecasting methodology for a one dimensional capacity-constrained highway. Five different prediction functions are tested; the best was selected according to the accuracy of projections against historical traffic data. The three-parameter logistic function produced more accurate projections compared to other functions tested when highway capacity constraints were taken into consideration. The R ² values at various test locations ranged from 88% to 98%, indicating good prediction capability. Using the Fisher's information matrix approach, the t-statistic test showed all parameters in the logistic function were highly statistically significant. To evaluate reliability of projections, predictive intervals were calculated at a 95% level of confidence. Predictions using the logistic function were also compared to those predicted using the compound growth rate and linear regression methods. The results show that the proposed methodology generates much more reasonable projections than current practices.     

密码技术及其应用

对信息安全所面临问题进行分析,然后回顾了密码学的发展历史,系统地探讨了现代密码学的一些主要算法,最后介绍了密码技术的几种应用。     

铁路货运发展现代物流的探讨

通过对铁路货运的优势分析,提出铁路货运发展现代物流的思路,并提出完善物流服务功能、建立快捷运输组织体系、拓展现有服务业务及加快现代物流人才培养的对策。     

上海内河货运量的组合预测

内河航运是综合交通运输系统中不可缺少的运输方式,存在着很大的潜在优势.定量地把握未来内河运输的发展趋势,具有重大的现实意义.通过利用时间序列模型、logistic曲线与自回归模型等,对2010-2015年的上海内河货运量进行预测.在此基础上,对不同模型赋予不同的权重,建立了组合预测模型.研究表明:未来上海内河货运量将持续稳定地增长.为提高预测的精度,有必要综合地使用多个预测方法.     

空气源热泵在港口的规模化集成应用

港口的节能环保新技术应用不仅体现在装卸设备上,而且应该涵盖码头装卸业务与后勤保障的全过程.在港口食堂、浴室的供热上,采用新型空气源热泵和能源循环组合集成技术,取代传统的燃煤、燃油、燃气加热的方法,大大节约了能源成本,实现了零排放.     

逆向物流管理理论与应用

该文通过实施体验和行业特点重新解读了逆向物流的定义和特点,分析了开展的必要性和当前的主要制约因素,指出开展过程中遇到的主要问题,进行总结和思考,结合自身开展业务取得的经验成果,提出了解决逆向物流运行发展中的存在问题的方法。     

船用柴油机综合保障系统研究

分析了船用柴油机综合保障概念和策略的发展及与柴油机维修性的关系,重点介绍了保障系统中维修计划管理;讨论了计算机辅助船用柴油机综合保障信息系统设计开发过程和系统主要功能模块,开发的原型系统可为进一步的实用系统研制提供参考.     

地下磁悬浮交通设计研究的若干问题

通过分析城市化带来的土地安全问题、环境安全问题、能源安全问题和交通事故引发的公共安全问题,详细论述了发展地下磁悬浮交通的动因。提出未来的城市交通和城际交通方式宜考虑发展地下磁悬浮交通,其中未来的城市客、货运交通宜发展地下中低速磁悬浮交通,而未来的城际交通宜发展成为绿色、低碳的地下高速磁悬浮交通。详细介绍了地下磁悬浮交通和地下物流系统的构造组成,重点介绍了地下磁悬浮系统具有节约土地、环境友好及高速大运量等优越性以及与该系统当前有关的试验研究成果,主要包括隧道的真空压力范围确定、截面设计、空气动力学试验模型、机械电力设备研究、生命支持系统研究以及建设成本估计等。     

Identification and interpretation of spatial–temporal mismatch between taxi demand and supply using global positioning system data

Taxis provide a type of on-demand mobility service in urban transportation. There are growing concerns regarding the level of service of taxis in satisfying residents’ mobility demand. However, the mismatch between demand and supply of taxi services has not been resolved even with the introduction of app-based vehicle services. In this study, three indicators are constructed using the Shanghai taxi global positioning system (GPS) dataset to reveal the spatial–temporal mismatch pattern. The issue is further analyzed via a case study, in which seven regions with frequent mismatch patterns are identified in the time period from 21:00 to 22:00. Then, a multinomial logistic regression model is employed to identify the demographic and built-environment factors contributing to the taxi mismatch problem. The study results show that population density, residential areas, the number of points of interest, and road density have significant relationships with the taxi undersupply. In contrast, the areas of commercial lands, as well as the other two transportation-related factors, that is, the number of bus stops and the distance to nearest subway station, are observed to be statistically significant for both “oversupply” and “undersupply” conditions. This study provides valuable insights for identifying mismatch patterns and interpreting the mismatch problem as a function of spatially explicit factors that are of great use for urban governance, especially in the improvement of taxi efficiency, taxi management, and urban planning.