An adaptive hawkes process formulation for estimating time-of-day zonal trip arrivals with location-based social networking check-in data

Location-Based Social Networking (LBSN) services, such as Foursquare, Facebook check-ins, and Geo-tagged Twitter tweets, have emerged as new secondary data sources for studying individual travel mobility patterns at a fine-grained level. However, the differences between human social behavioral and travel patterns can cause significant sampling bias for travel demand estimation. This paper presents a dynamic model to estimate time-of-day zonal trip arrival patterns. In the proposed model, the state propagation is formulated by the Hawkes process; the observation model implements LBSN sampling. The proposed model is applied to Foursquare check-in data collected from Austin, Texas in 2010 and calibrated with Origin-Destination (OD) data and time of day factor from Capital Area Metropolitan Planning Organization (CAMPO). The proposed model is compared with a simple aggregation model of trip purposes and time of day based on a prior daily OD estimation model using the LBSN data. The results illustrate the promising benefits of applying stochastic point process models and state-space modeling in time-of-day zonal arrival pattern estimation with the LBSN data. The proposed model can significantly reduce the number of parameters to calibrate in order to reduce the sampling bias of LBSN data for trip arrival estimation.     

客车行业的本质及其技术创新与品牌传播

从产品属性、价值传递和市场营销的角度,分析客车行业的本质;基于客车行业的本质,阐述客车企业技术创新和品牌传播的主要内容。     

Exploring the distances people walk to access public transport

ABSTRACT

A shift from private motorised transport to more active transportation can, among other things, deliver significant health benefits. The main disadvantage of active transport (in particular walking) for most people compared to private motorised transport is the limited range. Public transport (PT) can complement the use of active modes and extend their range. Therefore, there might be potential to increase physical activity through an increase in PT use. This article takes a closer look at how walking relates to the use of PT by examining existing literature on the topic. It aims to study how far people walk to and from PT and what key factors influence this. Scopus, Transport Research International Documentation and Web of Science have been searched systematically for relevant articles, conference papers and books. After screening of titles and abstracts, 41 relevant publications were identified. Studies were included if they quantified the amount of walking (measured as either distance or time) that is directly related to the use of PT. Studies that quantified walking using general measures of daily physical activity or daily walking or that used stated preference designs were excluded. The PT systems considered in this paper are mass transport systems in urban areas, either road- or rail-based, with fixed schedules and stops. Demand responsive transport services, which can offer door-to-door travel, are not considered, as these systems can to a large extent eliminate the need to walk. In the identified publications, a large variety of walking distances and times have been reported, and these seem to be highly context-specific. The paper establishes the evidence for the wide range of factors that influence walking related to PT, which have been categorised as personal, PT-related, environmental, and journey-related. The different methods that have been used are discussed by critically analysing their advantages and limitations. Only a limited number of these methods used allow for an accurate assessment of the walking distances to and from PT. The paper concludes with suggestions for future research, such as a need for more accurate measurement of walking and research in different geographical areas to shed light on underlying influences of culture and climate.     

赴日、韩考察的几点体会

介绍了作者赴日本、韩国进行专业技术考察的情况 ,谈了几点认识和体会。     

高速公路服务区司乘人员活动规律与设施布局

服务区内司乘人员出行活动规律是进行服务区设施布局的重要依据。好的服务设施空间布局应该和司乘人员活动规律相一致,这样才能提高服务设施利用效率和交通秩序,为司乘人员提供更便利的服务。鉴于此,重点针对京秦、沿海高速公路服务区内司乘人员活动规律进行调查研究,并结合活动链原理提出服务区设施布局形式。     

世界主要区域港口国检查组织实施情况

港口国检查(port state control,简称PSC)制度实施近20年来,其依据不断变化,已经生效和即将生效的公约修正案不断对船舶应对PSC检查带来了新的挑战,PSC政策研究应该是一个持续的过程。通过对五个主要区域港口国检查组织近两年实施PSC检查的情况进行统计分析,展示了PSC实施过程中各地区的差异性,为各航运公司更好地应对PSC检查提供了新的参考依据,同时,根据我国船舶应对PSC检查的现状提出针对性的措施。为确保我国船舶顺利通过检查,对船舶检查具有重要的指导意义。     

The public's understanding of the functionality and limitations of automatic braking in Japan

Automated driving systems are increasingly widespread in the automotive industry. To operate automobiles that are assisted by such systems, drivers must correctly understand their functionality and limitations. Hence, focusing on the rapidly spreading technology of automated braking, this study seeks to clarify the general public's understanding of automatic braking systems. A total of 210 Japanese people responded to a questionnaire regarding how automatic brakes are operated, how they work, when they disengage, and so on. The proportion of those who misunderstood the operation of the system is not especially high, but there were a certain percentage of people who had misconceptions; e.g., some believed that automatic braking could detect pedestrians or bicycles. Moreover, respondents were under the impression that drivers cannot readily disengage automatic braking systems. If they mistakenly use the automatic brake, there is a possibility of posing a risk to the road transportation system.     

重型汽车维修性设计研究

维修性设计是整车开发过程中的重要组成部分,良好的维修性能够减少用户的维修时间,提高车辆运营效率。针对重型汽车开发过程中维修性设计,从定性和定量两方面给出设计要求及对应的分析评价方法。从简化产品设计、可达性和可操作性等方面建立维修性设计准则作为产品维修性的定性要求,并以满足的设计准则数量与设计准则的总数量之比来判断满足定性要求的程度对于定量要求,通过维修活动时间历程分析对维修时间做出预计,恨据预计结果判断是否满足指标的要求。     

扎实开展创先争优 推进学校内涵发展

本文立足学校实际,深刻分析了开展创先争优活动的重要意义,阐述了开展创先争优活动需要把握的重点内容,明确了活动开展要紧密结合实际,突出实践特色,注重六个结合,实现内涵发展目标。