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While facing the needs for Vehicle Infrastructure Integration (VII) applications in traffic management, the paper deals with the problem of locating Road Side Units (RSU) for VII deployment. After analyzing the difference between traditional problems of locating traffic information detector and the problem of RSU location, a significance ranking model for RSU localization and three kinds of Significance Degree (SD) computing strategies are put forward. A VII simulation environment for the purpose of RSU localization optimization within VISSIM microscopic traffic simulation software is established developing add-on functions using VISSIM's Component Object Model (COM). A VII test bed of the Olympic Park network in Beijing is taken as an example to evaluate the performance of RSU localization model. The results of simulation experiments indicate that the mixed SD strategy considering both speed and route monitoring is superior to the other two SD strategies. Then, the impact of RSU number and OBE market penetration rate on the evaluation measures of traffic monitoring are studied with reference to the proposed mixed SD strategy. In this case, the evaluation measures of optimized RSU configurations generated by the ranking algorithm are always better than those of random RSU configurations. In addition, the benefits of optimized RSU configurations increase along with RSU number and market penetration rate while the benefits of random RSU configurations are more fluctuant. [ABSTRACT FROM PUBLISHER]

Currently, the subject of housing in China is of great interest to many researchers, since improvements in living conditions for the largest population in the world have not kept pace with the territory's economic growth. This paper describes basic social housing situations in China, and assesses the inequality in housing reform since 1990s as a result of overall economic improvement. In order to reduce the degree of inequality in China's social housing, this paper is focusing on the policy management of access to economically affordable housing because housing affordability in China is a pressing social and economic issue, particularly for low-income families due to an unreasonable mechanism. The related policies are analyzed in is paper by using incentive mechanism design, which reveals that supervision and announcement system, the restriction in current mechanism, and the area of economically affordable house are critical for the effectiveness of present polices. Furthermore, a housing area calculation model based on the incentive mechanism design is presented and an illustrated case of Beijing City is also conducted, which can maximize the utility of government considering incentive compatibility. Finally, some policy suggestions are explored including enhancing external environment and establishing internal mechanism. [ABSTRACT FROM AUTHOR]

Road safety conditions in China have worsened following rapid urbanization and motorization. For a long time now, China has ranked first in the world in the number of road accidents and fatalities. Therefore, evaluating safety levels is essential to implementing effective countermeasures. For developing countries like China, however, assessing safety levels via crash data statistical analysis is difficult because of limitations on a short history of collecting crash data, small samples and an incomplete collection of information. To address these limitations, the method of surrogate safety analysis using the traffic conflict technique (TCT) has become a widely used evaluation procedure. On the basis of the mechanism analysis of TCT, the paper presents a conflict hazardous assessment model (CHAM) for the mixed traffic safety evaluation of urban intersections. In the proposed model, the principle of the conservation of momentum is used. CHAM is a model used for assessing safety levels from the aspects of severe conflict numbers and conflict hazardous levels (CHLs) when traffic conflicts among mixed-traffic modes occur. Factors such as the conflict type and conflict angle of different traffic modes, weight and velocity are considered and incorporated into the model through the integration of the accident collision theory and the head injury criterion (HIC) index for head hazard assessments. The calibration and validation of CHL models are also carried out using 341 intersection crash reports in Beijing from 2006 to 2008. The results show that the established CHL models have good validity. [ABSTRACT FROM AUTHOR]