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To effectively develop road networks under budgetary and time constraints, high-standard arterial expressways in Japan incorporate dual four-lane roads with provisional two-way two-lane (TWTL) sections in areas of low traffic demand. In the majority of TWTL sections, rubber poles are used to partially separate inbound and outbound lanes, but safety risks, including head-on collisions resulting from lane departures into an opposite-direction lane, are considered problematic. To urgently address this situation, wire ropes were installed along some road sections nationwide to verify their effectiveness in preventing head-on collisions. This paper presents a multifaceted evaluation study of the effectiveness of wire ropes on TWTL sections, including drivability, maintainability, and effectiveness in accident prevention.

The function of parking areas at expressway rest stops is to provide drivers with opportunities to park their vehicles for their own purposes, so the number of parking spots has been discussed. However, as the number of parking spots increases, the parking area becomes maze-like and the use of the parking spots becomes inefficient. This leads to skepticism that an increase in parking area capacity will contribute to enhancing parking area performance. Meanwhile, one vehicle is able to park in a parking spot when another vehicle exits the area that is fully occupied, so the condition of drop-by traffic at a rest stop can be discussed using the queuing theory by viewing a rest stop as a warehouse. Thus, this study aims to determine the applicability of the queuing theory when discussing drop-by traffic situations, while assuming a first-in first-out (FIFO) condition. For the applicability of the queuing theory of describing parking area performance, this study employed the electronic toll collection (ETC) probe time-stamp data. The observed values from the ETC probe time-stamp data and FIFO assumed time lags are described, and the applicability of the observed ETC time-stamp data to representing the exact conditions was determined by comparing the number of vehicles parked on the hour every hour and those counted by the observed ETC probe time-stamp data. Finally, the applicability of the FIFO assumption was discussed using the correlation between the observed ETC probe time-stamp data and the FIFO assumed time lags calculated by the data. The results indicate that a FIFO assumption could alternate the observed the ETC probe time-stamp data. The number of vehicles staying on the hour every hour can be represented by the calculation results from FIFO assuming time lags. These findings show that it could be possible to determine the congregative situations of an expressway rest stop analyzed by the ingress and egress time-stamp records. Also, this result assumes any contribution to assessing the functional performance by measuring only the number of vehicles entering and exiting a parking area.

In the summer of 2008, two hurricanes made landfall along the Texas coast causing billions of dollars in damage. Texas received presidential disaster declarations, which resulted in the state receiving over $350 million in hazard mitigation funds. Over 500 requests for mitigation projects were submitted to the government from communities impacted by these disasters, but not all requested projects could be funded. As a result, those communities that submitted requests for well-defined mitigation projects were the primary benefactors of the federal mitigation funds. To better understand the factors that characterize a “well-defined” mitigation project, a study was initiated to develop an index for rating the completeness and quality of mitigation project definition. The study incorporated concepts from research on the quality of community planning and from project definition rating methods. A rating tool was developed to evaluate projects that have been successfully funded and to contrast them with projects that have been rejected. The rating tool consists of detailed descriptions of the project scope elements along with a method for scoring the completeness and quality of the project's definition. This paper presents the research results and the outcome from comparing six mitigation project definition packages.