Strategy and program analyses using option evaluation systems (OESs) such as HDM-4 have been powerfully used for exercising pavement management planning at the network level. Theoretically, there is no distinction between strategy analysis with dynamic sectioning (SDS) and program analysis, and the results of SDS analysis may be used directly to identify the most appropriate single or rolling multiyear work programs and contract packages for individual sections of a road network or sub-networks. However, techniques for doing such an analysis have not been well presented. Therefore, the objective of this paper is to provide a systematic procedure as a guideline for identifying single or rolling multiyear work programs under given budget constraints where the SDS is utilized. The presented procedure employs HDM-4 as an OES for the purpose of demonstration, but it is deemed to allow almost any OESs.

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This paper provides information on the configuration of the Elevated U-turn that is finally constructed along C5 as alternative to the initial C5/Kalayaan underpass and C5/Vargas-Lanuza overpass plans. It further gives an analysis on its expected performance as an infrastructure that will meet the current and future traffic demand. Specifically, the level of service at peak hours are computed and assessed. Further qualitative analysis discussed the advantages and disadvantages of the U-turn flyover. Several road safety issues have been identified with regard to the new facility and this review recommends some strategies to mitigate risks.

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This paper demonstrates the study of a footbridge's design and also the analysis of the dynamic behavior of the structure due to human-induced load. The bridges are located in Surabaya. Firstly, the human loading as a vibration source of the footbridge is presented together with the model force of the loadings. The next section is the design of the bridge subjected to dynamic load from British Standard, AASTHO and Eurocode. Then the dynamic behavior of the structure is studied using three Tunjungan footbridges as examples. Finally SDOF system is used to calculate the footbridge vibration induced by human load and this is presented and applied to the Tunjungan footbridges, which is very helpful to calculate in practice. The conclusion can be drawn from this study is that the dynamic behavior should be considered in the design of the footbridges due to human-induced loads and using SDOF system is accurate enough to calculate the structural responses of the bridge.

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In a multi lanes-two ways divided road, lane changing behaviour is more important than overtaking behaviour. In this paper the lane changing behaviour on a six lanes-two ways divided urban freeway will be discussed. A 24 hours observation was carried out in urban freeway segment adjacent an arterial road. A video camera was installed in a nearby pedestrian crossing bridge to record 24 hours traffic movement of the freeway. Desk observation was then carried out by playing back the video. For each type of vehicle, the number of several movements were recorded every 15 minutes. These include lane changing to the left, lane changing to the right, overtaking from the left and overtaking from the right. The percentages of each type of movement relative to the number of vehicle for each vehicle type for every 15 minutes period were calculated. The correlations between these percentages and V/C were calculated.

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Delay is an important factor in the optimization of traffic signals and the determination of the level of service of a signalized intersection. The paper proposes the modified Webster formula to estimate the delay of vehicles at signalized intersections under mixed traffic conditions. The passenger car unit is estimated by using the multiple regression analysis. Distributions of the saturation flow are developed and proved to follow the normal distributions at three studied intersections. The expectation function method and Taylor series expansion are then utilized to estimate the mean and variance of delay. A comparison between the proposed model and the conventional Webster model and observed delays are performed to present the improvements of this model.

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While many developed countries have typically been facing problems related to four-wheeled traffic, developing countries are facing problems related to small motorized vehicles, such as motorcycles. However, very few studies have been conducted to the traffic operation of motorcycles in the existing literature. This study proposes the methodology to estimate the motorcycle unit with a consideration of dynamic characteristics of moving vehicles. It expresses the relationship between speeds and occupied spaces with respect to motorcycles and other types of vehicles. A case study is introduced in order to estimate the parameters of proposed formula by using microscopic traffic data at three mid-blocks in Hanoi, Vietnam. Then, the proposed methodology is compared with previous methods. The results show that the proposed formula represents the best among them. The findings provide useful information that can be used to develop the speed-flow relationship, estimate highway capacity, analyze level of service, and formulate effective traffic regulation and control measures.

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Variable Message Sign (VMS) is one of the major components of intelligent transportation systems (ITS). In particular, portable variable message signs (PVMS) are very useful in managing traffic events including work zone, special events, and incidents. It is essential that PVMS locations and message operations should be designed with the proper consideration of driver's legibility distance. This study aimed at establishing a functional relationship between legibility distance and causal factors based on extensive field experiments. A differential global positioning system (DGPS) in a control vehicle was used to obtain legibility distances. The proposed model based on multiple linear regression would be greatly useful for ITS designers and planners when making decisions on PVMS locations and message operations for better traffic management.

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This research unveils the factors that affect urban street bottleneck capacity through the use of oblique cumulative plots for traffic analysis on Henry Dunant Road, a busy urban street in Bangkok. Detailed observations on the street reveal that the street bottleneck capacity was affected by several factors such as illegal blocking parked cars, interrupted U-turns from the opposing direction, and interrupted crossover right turns from an access road. In order to analyze the quantitative effects from these factors, four days of traffic data at the study site were collected by video cameras, manually extracted, and plotted using the oblique cumulative curves such that traffic mechanism at the site can be examined by visualizing the changes in flow rates from each different measurement and comparing across observation days. The analysis results show the degrees of how these individual factors affect the street bottleneck capacity.

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In Taiwan latest revised HCM, straight lanes and un-opposed left-turn lanes at signalized intersections were respectively divided into six types and four types in officially. The field data showed that queue discharge characteristics varied with the lane type and the location of the city, and the nonlinear regression models could accurately describe the discharge behavior of each lane type. Based on these regression models, the influence of the city location factor, fz, could be used to adjust the queue discharge behaviors among different cities. Therefore, this study collected queue discharge data in several Taiwan cities, performed statistical analyses, and compared the field data to determine fz. It was found that fz is an important parameter for comparing queue discharge behavior among cities in this study.

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This paper develops a novel travel time forecasting model using artificial neural networks with feature composition. The core logic of the model is based on a functional relation between real-time traffic data as the input variables and actual travel time data as the output variable. Feature composition is employed to reduce the data features with fewer input variables while still preserving the relevant traffic characteristics. The forecasted travel time is then obtained by plugging in the real-time traffic data into the functional relation. To validate the model, sufficient amounts of actual travel time and real-time traffic data are collected from Taiwan freeway intercity buses (equipped with global positioning systems), roadway vehicle detectors and the accident database. The proposed travel time forecasting model has shed some light on the practical applications in the intelligent transportation systems context.

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This paper aims to develop automatic incident detection models based on a genetic fuzzy logic controller (GFLC). Two approaches are used to overcome the problem that GFLC can not consider too many state variables simultaneously. The first approach is to partially select three variables from all available traffic information (nine variables) as state variables of four GFLC models. The second approach is to extract first three principal components from the original nine variables as state variables of GFLC model, namely the Components model. For comparison, artificial neural network (ANN) incident detection models are also developed. To investigate the applicability of the proposed models, three commonly used indices: detection rate (DR), false alarm rate (FAR) and mean time to detect (MTD) are used to measure their performances. The results show that the Components model outperforms among all these incident detections models with DR=100%, FAR=1.21% and MTD=12.3 seconds.

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Conducting traffic control duties at urban intersections significantly affects the operating efficiency of traffic in peak hours. How to make a good personnel allocation plan is a very important issue for urban traffic management. Therefore, this study constructed a manpower demand evaluation model of three objectives and nine criteria based on two-stage questionnaire surveys. The relative weight of the criteria was determined by the analytic hierarchy process (AHP). The generalized score of this evaluation model can be used to measure the need of traffic control manpower for urban intersections. According to this generalized score and a practical rule-of-thumb, this study proposed the personnel allocation principles further. Finally, this study found that the proposed model and principles are feasible by applying to two cases of the Taipei Police Districts.

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Traffic conditions of DKI Jakarta road networks, including the freeways have been getting worse and this leads to higher transport costs. It is very important that the users obtain benefits, i.e. lower transport costs. At this moment the traffic performance has been predicted using either IHCM (DGH, 1997) or other models such as those developed in HCM 2000 (TRB, 2000). Research has been carried out aiming at modelling traffic at Jakarta freeways based on traffic measurement. Furthermore models of user costs, i.e. vehicle operating costs, VOC and travel time costs, TTC were developed. It was found that the capacity of freeways to be higher than the capacities predicted by IHCM (DGH, 1997) and HCM 2000 (TRB, 2000), i.e. 2651 pcu/lane-hour, compared to 2208 pcu/lane-hour and 2250 pcu/lane-hour respectively. The transport costs per km at Jakarta freeways were found to be Rp. 2,513.-; Rp. 10,497.-; and Rp. 4,277.- for passenger cars, buses and good vehicles respectively.

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The objective of this study is to find some factors determining the difference of design speed and speed limit between Japan and Korea. The manner of speed limit setting and the historical change of road geometric standard in Japan and Korea are investigated by conducting interview surveys to several road facility and traffic control administrative offices. We find out that speed limit is same as design speed in many road types in Korea while speed limit is less than design speed in all road types in Japan. We can observe that Korea succeeded in changing her road geometric standard taking the actual condition into account, while the challenges for taking the actual condition into account have been completely escaped in Japan. In consequence, we extract three factors for the differences, national consensus to safety, volition toward the orientation of foreign models, and leadership and challenge sprit.

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The understanding of merging operational quality for expressway is very important to transportation engineers in order for planning, designing and maintaining the highways. Projected traffic demands along with the estimated ability of facilities in carrying traffic are crucial inputs to the planning of infrastructure expansions. Traffic engineers normally utilize traffic models prediction to anticipate congestion and potential breakdown at critical areas and through this approach they are able to develop appropriate countermeasures and route diversion strategies as well as in developing traffic management strategies to solve the congestion on the expressway. Merging Flow rates models were successfully developed and validated in these studies that are needed in order to understand the merging operation at ramp junction. The models are for estimating flow rates in lane 1 and 2 immediately upstream of the merge influence area.

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This study proposes a modified asymmetric simple exclusion process (ASEP) approach to simulating low-to-high traffic densities, from which the three-phase traffic phenomena are explored. The chronologically-ordered flow, speed and occupancy data extracted from Taiwan freeway's dual-loop detectors are analyzed and tested. The observed traffic features do exhibit free-flow phase, synchronized-flow phase, and breakdown phenomena, which can also be elucidated by the simulated results with the proposed approach. Paired traffic parameters are displayed by their relations and by their chronological order so that more insightful traffic features are explored.

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This paper presents an approach and a case study to traffic responsive signal control in mixed traffic conditions. Inductive loop detectors are not likely to be a feasible option in many fast growing cities of developing countries due to heterogeneous, often very congested traffic conditions with no lane discipline. Therefore, the approach used in this paper is based on identifying traffic conditions through bus travel time information obtained through direct vehicle to infrastructure communication. The approach is embedded in the MOSCUE framework (multi-objective signal control in urban areas) which allows the decision maker flexible adjustments of the signal controller to possibly changing policy objectives. The feasibility of the concept is illustrated with a case study from Ho Chi Minh City, Vietnam. It is shown that even if only buses transmit travel time data the controller can achieve some improvements in overall traffic performance.

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If the current adaptive cruise control systems(hereafter referred to as ACC) is fitted to vehicles running on expressways, the occurrence of congestion will be relieved by maintaining the appropriate following distance. However, it does not have the function of appropriately controlling starting and following of a vehicle in congestion, so it is considered that once congestion has occurred, ACC is not useful for faster clearing of the congestion. Therefore, in this research an advanced ACC is proposed in which the function of starting and following is added to conventional ACC, and an estimate of the extent to which congestion would be relieved by installing this to vehicles was made based on current traffic data. The results indicate that, for example, when 25% of vehicles are installed with advanced ACC, the congestion volume would be relieved by about 40%. This shows that faster clearing of congestion can be achieved by increasing the use of advanced ACC.

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This paper investigates the effects of motorcycles on traffic operations at signalized intersections. Field surveys are conducted to study the effects of motorcycles on other traffic by examining discharge headway. It is found that the effects of motorcycles may be measured in terms of an increase in the start-up lost time of signal phase. Presence of motorcycles does not affect the saturation headway of traffic. A microscopic traffic simulation is developed so that effects of motorcycles can be taken into account in the planning and management of urban streets. It is found that our software can replicate the discharge headway as observed from the actual data.

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This paper investigates the methodology of motorcycle equivalent unit (MCU) at road-segments in motorcycle dependent city. A methodology based on passenger car equivalent (PCE) approach previously developed by Chandra et al. (2003) is presented in this research. This methodology illustrates a more accurate method of MCU in mixed traffic flow by considering the characteristics of moving vehicles such as velocity and an effective space. In which, the effective space of each kind of vehicle is computed under considering influences of velocity and physical size of the subject vehicle and the surrounding motorcycles. The proposed methodology was applied to field data collected at eight sections in four road-segments located in Hanoi city, Vietnam. The field data indicated that the effective space of each vehicle varies by the speed of moving vehicle, and MCU value increases slightly corresponding with the lane number of each urban road during the peak hour. Also, it was found that the MCU is a function of the mean speed, a mean effective space of each vehicle. The field data indicates that the MCU values of car, bus, minibus, and bicycle are 3.43, 10.48, 8.34 and 1.38, respectively at road-segments in urban road.

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Advanced Traveler Information System (ATIS) has been applied in many countries. Yet the effectiveness of the system is heavily dependent on driver's behavior and response to the given information. The behaviors are somewhat unique for specific individuals (cities). The objective of the paper is to analyze the behaviors of drivers in different Southeast Asian cities, Bangkok (Thailand), Kuala Lumpur (Malaysia), and Singapore (Singapore), pertaining to changing route under influence of traffic information availability and travel situation. The results illustrate that the behavior of drivers in the three cities are different pertaining to the factors that affect them to change the route.

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Traffic calming measures aim at slowing down vehicle speed, and then enhancing traffic safety and reducing traffic noise on local residential streets. Speed bump is one of the most popular traffic calming countermeasures. However, sometimes, the installation of speed bump was protested by the residents in Taiwan due to traffic noise generated additionally. Therefore, this study was conducted to assess the acceptable level of noise on local streets, and furthermore, to develop the Acceptable Level of Noise assessment model. Using Fuzzy Classification Method, the Acceptable Level of Noise is classified based on the resident subjective feeling on the noisy traffic situation. Applying it, the Acceptable Level of Noise on local residential streets can be identified for deciding the installation of traffic calming countermeasures.

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Intelligent Transportation Systems (ITS) focus on increasing the efficiency of existing surface transportation systems through the use of advanced computers, electronics, and communication technologies. The interaction between signal setting and traffic assignment is an important issue in designing efficient ATMS. This research focuses on finding dynamic user equilibrium between signal setting and route assignment. The problem is solved through a bi-level framework. The upper level solves for signal setting parameters, including cycle length, green splits, and offsets. The lower level solves for time-dependent user equilibrium (UE) flows in a traffic network. The signal setting is adjusted through two methods: the Webster formula and Adaptive Signal Control. Dynamic UE flow patterns are solved through a simulation-based DTA model, DynaTAIWAN. This bi-level framework can be applied in cities with signalized networks. Numerical experiments are conducted based on a subnetwork of the Kaohsiung City to illustrate the proposed framework.

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Travel time is used for performance measures of the developed transportation system. Among many other advanced techniques, Automatic Number Plate Recognition (ANPR) has gained lots of intentions because it is a non-intrusive approach and this system do not required any additional vehicle identification need to be installed to the vehicle. In this paper, a new real-time ANPR system is presented. The proposed ANPR system has been developed to suit with traffic environment in Malaysia. The development of the ANPR system consists of several processing steps such as vehicle detection, number plate localization and extraction, character segmentation and recognition. A number of tests were done in order to measure the performance and capability of the developed ANPR system. Based on the results, the system is reliable and robust and its capability to measure travel time indicated that it have huge potential to be use in traffic and transportation studies.

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As traffic flow has been worsening, congestion causes poor traffic management performance, and negative impact on economic productivity as well as environmental quality. The focus of research is to find the recent traffic's fuel consumption character in congested network, in terms of geometric, vehicles and traffic data. Survey was conducted in Bandung, representing the congested cities in Indonesia. Research finds that during last 9 years since TRRL test, average travel speed has been decreasing more than 40 percent. The analysis is developed utilizing 3 methods, driving cycle's principle, Greenwood's noise acceleration, and hydro dynamic traffic model. Commercial and private vehicles are tested, using benzene and diesel, with various engine cylinders. the output of research will give contribution for understanding behaviour of fuel consumption, from then the alternative to reduce oil consumption would be developed.

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There are many researches on traffic flow dominated by passenger cars in developed countries. However, few researches have been done concerning traffic flow dominated by motorcycles in developing countries. Thus, this study addresses the calculating methodology of Motorcycle Equivalents Units (MEU) of bus based on the delay at signalized intersections in urban roads in motorcycles dependent cities. For signalized intersection analysis, the methodology of delay based Passenger Car Units (PCU) for trucks by Zhao et al. (2000) is developed to measure MEU of bus based on the delay under mixed traffic conditions. MEU is a function of average delay of motorcycle in homogeneous case and additional delay due to each bus in heterogeneous case. The validating of proposal model based on the comparison of departure rate process at signalized intersection using the value of MEU of bus.

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In Japan, and also in other Asian countries, intersections with very long signal cycle time have been problematic especially form pedestrian viewpoint. This research aims to suggest one technique to solve the problems: two-step crossing system with cycle time reduction, as a new standard of intersection design in Japan and other Asian countries as well. To check the effects of it, an experimental attempt are conducted in a real intersection and analyzed through a video survey and an interview survey. As a result, we revealed how much the effect differs by pedestrian walking direction and that lots of pedestrians accept this kind of experiment and think about the future extension. For future task, installing sound signals and remaining-time indicators, and applying different cycle time will be necessary to make this technique new Asian standard of intersection designing and controlling.

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An algorithm to track vehicles and determine traffic flow parameters through images generated by a surveillance camera in real time is developed. It aims to obtain traffic parameters such as vehicle count, vehicle speed, vehicle time headways, traffic volume and vehicle classification from a complex traffic scene. Two different video vehicle detection algorithms were developed for two different image types in processing, namely grey scale image technique and colour image technique. The vehicle is detected due to the difference of pixel value with the threshold value. Vehicle classification employed in this project is length based classification. Both methods give a high accuracy in vehicle detection and classification result. From the experiments which are done in real time, the accuracy of traffic parameters obtained is more than 80%. The develop algorithms may can be applied to various site locations with different luminance and lighting condition.

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Excessive growth of motorcycle in Indonesia resulting a problematic to the society particularly road users. Three motorcycles market rank are China, India then Indonesia. Aggressively, motorcycles industries expanded their manufacturing capacity to meet the local market and overseas, as well as dealers and agents were intensively conducting distribution and tempted marketing. Social and economic impacts of motorcycles use may include: economics growth, traffic accident, traffic jam and the environment impacts. This paper outlines some policy instruments that are possibly applied to control motorcycles negativity impact. Besides its utility, motorcycles growth and usage need to be restricted, effective policy instruments should be sought in order to minimize risk and protect the public interests. Some research agendas for the continuation of the study are also outlined.

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The current loss time estimation and intergreen time design methods in Japan lack sufficient consideration of the characteristics of right-turn traffic, such as right-turners behavior as well as clearing distance and speed under various phases. Utilizing field data, this paper first examined loss time estimation method under the permissive-and-protected right-turn (PPRT) and protected-only right-turn (PORT) phasing plans. Results showed that the current method is very likely to overestimate loss time. Two modifications to the current method for the PORT and PPRT phasing plans respectively were then proposed to provide more accurate and sophisticated estimation. Meanwhile, intergreen time design method was examined. It was found that the current method tends to generate unnecessarily long all-red times for right-turn traffic as compared with German method. Thus, it is suggested that the applicability of German method in Japan needs to be investigated to reduce loss time as well as cycle length.

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This study contained to develop a real-time signal control algorithm based on the sectional travel time and confirmed the reduction and equalization of delay by approach which was the objective function of the algorithm as against TOD control by the field test. The dissolved time of queue was calculated, using the average delay and detection time of probe vehicles, which was collected during the accumulated cycle. Then a delay variation and a targeted red time were calculated, and a phase assignment was conducted. This study was conducted to develop a real-time traffic signal control algorithm based on sectional travel time of individual vehicles, using general-purpose traffic information detectors. With the current of disseminating ubiquitous technology, the aim of this study was a fundamental change of traffic signal control method.

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Uninterrupted facility forms interrelation of cause and effect among traffic volume-speed-density, so if ramp traffic flow is merged into main, not only single variable such as speed or density but also qualitative change of traffic flow are caused by correlation. Thus, this study used the traffic data which are continuous temporally and spatially in various of traffic conditions, to find out correlation change section by speed-density traffic flow model. As a result of analysis, it was found that downstream section where traffic flow (decelerated by merging) is recovering changed to "Greenshields" model, and that spatial transition occurs as traffic flow moves farther towards downstream (starting from merge terminal point of lane 3), change section would shift to inner lane within the extent of downstream 100m~500m. It was also discovered that upstream, merge and downstream(which were applied as section dummy variables) showed heterogeneous traffic flow characteristics.

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As a part of a public transportation information provision, the Bus Information System (BIS), which has been recently advocated by the city governments of South Korea, provides bus arrival information and bus location information to users. The reliability index and level are evaluated differently in each city. As the evaluation is performed, without considering prediction size and range, the evaluation result cannot be fed back to the BIS. Therefore, this study derived time range and spatial range of bus arrival information based on the results of a survey. 'User allowed range' and 'User allowed error' can be selected as the range of the evaluation and the level of the evaluation. The accumulation probability of the absolute error can be selected as the reliability evaluation index. Thus, this study showed the methods of selecting evaluation range, index and level for the evaluation of real-time bus arrival information reliability

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Traffic lights are used around the world to control traffic flow in urban road networks in an efficient way. Especially in higher-ranking road sections of road networks, neighbouring intersections with signal control are normally coordinated between each other in order to serve traffic volume on a high quality level. In periodical time intervals, the coordination of signalised intersections needs to be analysed. In this way, it is possible to identify defects in signal control and to adapt traffic control to changed conditions. In this paper, a method for "Analysis of Traffic Flow in Coordinated Sections in Urban Road Networks by Application of up-to-date Low-Cost Methods" will be presented. The developed method can be used for assessment of the traffic flow as well as for identification of defects in signal control in coordinated road sections. It is a stand-alone solution which can be applied independently from local technical equipment of traffic lights.

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This paper uses simulation models to demonstrate the traffic conditions in Ho Chi Minh City under different scenarios of levels of car and bus use. To predict the negative impacts of shifting from motorcycle to car use which is likely to occur in the future, 4 scenarios, i.e. 10%, 20%, 40%, 60% car use, were simulated. The results show that if 30-40% of motorcycle users shift to use car, traffic conditions would significantly worsen. Further analysis indicates that behavior change of private mode users to become bus users would have large effects on maintaining acceptable travel speeds. Based on these results, the study suggests that managing travel demand, i.e. restraining car use, and promoting bus usage is crucial to ensure the mobility of the city.

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This paper studies the departure time and route choice problem (DTARCP) for the development of online routing applications in advanced traveler information system (ATIS). The DTARCP is defined as to determine optimal departure time and reliable shortest path simultaneously in stochastic and time-dependent (STD) networks. It is motivated by the fact that travelers make these two decisions inter-related in STD networks. We propose a new model for modeling the DTARCP. An efficient heuristic solution algorithm is developed to solve the new proposed model. Numerical results based on real-world ATIS are also presented to demonstrate the features of proposed model and solution algorithm.

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Urban traffic in Phnom Penh is characterized by the high level of mixed traffic with an extremely high proportion of motorcycle. Rapid growth of motorcycle with its behavior in traffic is the main cause of road congestion and accident. Recently, there is also a drastic increase in number of light vehicles including car, pick-up, and van causing a more serious problem on traffic capacity and safety. Firstly, this paper investigates the traffic performance of motorcycle-dominated urban street under different proportion of light vehicle, whereby particular observation on how motorycle responds under different proportions of light vehicle is conducted. Data was collected using videotaping technique. Secondly, the present paper examines motorcyclists perception on traffic safety issue and the extent to which they involve in traffic accident based on motorcycle driver interviewer survey. Finally, discussion on how to improve capacity and safety is made.

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Current follower recognition methodologies are based on single critical headway values that may not accurately identify followers since they do not take into account the randomness of preferred tracking headways and drivers desired speeds. This paper presents an improved, probability-based follower identification methodology that takes both of these factors into account while also considering their variability across different driving conditions. The calculated follower percentage and follower density values were compared with those estimated using the 3-second threshold suggested by the HCM. The proposed methodology estimated more followers, particularly during periods of heavy flow, highlighting the inability of using a single headway value to correctly identify followers. The resulting follower counts have been normalized, making it possible to theoretically identify followers at any given time or driving condition.

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The objective of the study is to develop a signal-control strategy for work zone on two way two lanes roads which is treated as an isolated intersections during severe over saturation. The Modified Maximum Throughput Model simulation on work zone traffic control was done on 6 meter road width and workzone speed 20 kph with the variation of work zone length. The study gave indication of maximum work zone length and cycle time to accommodate over saturation traffic condition.

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The speed - flow characteristics determine the fuel consumption and other road user cost components. Hence, it is necessary to understand the speed - flow characteristics, which directly influence the road user costs. In India, road transportation has come to play dominant role by virtue of its flexibility and the expansion that has taken place in the road network and vehicle technology in the last three decades. In recent past the massive road expansion projects to six lanes and eight lanes are taken up on BOOT/BOT basis. Hence, it is essential to study these changes in speed - flow characteristics of multilane highways, which in turn would be useful in estimating the road user costs. Therefore, an attempt has been made in this paper to present the speed - flow characteristics on Indian highways on multilane highways/expressways in plain terrain. For the present study NH8 Delhi- Gurgaon Access Controlled Expressway have been considered

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The improper design of traffic signal can be a cause of accident such as driver can not pass a large intersection because of insufficient of Intergreen time. Intergreen time is duration time of the clearance part of the phase corresponding to the period between the phase change point and the beginning of the green display for the next phase. In Thailand, design guideline suggests that Intergreen time is the minimal time that the accident will not be occurred and the least time is 4 seconds. However, the comparison study with international design guidelines from Germany, Hungary and China; their guidelines consist of description and formula to determine the Intergreen time clearly. The Intergreen time depends on multi factors such as distance, design vehicle and speed. This paper describes the comparison the intergreen time among four countries.

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The Central Java region is located in the central part of Java Island and encompasses major inter-regional and intra-regional freight corridor. The Central and Local Governments, however, are not capable of maintaining their roads with high service level due to rapid deterioration of pavement by overloaded trucks as well as budgetary constraints. This paper proposed a new weighbridge survey method with minimum resource by utilizing daily operation of weighbridge stations. Overload analysis based on the survey data revealed that bulky commodities, particularly steel and cement, damaged the pavement. The commodity weight OD table estimated by the survey data also revealed that the bulky commodities are transported across Java Island. The methodology for estimating the economic benefit of pavement cost reduction by transportation project using the survey data was proposed and a case study was conducted for the new freight railway project along Semarang - Solo - Yogyakarta corridor.

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Simulation softwares were developed for the past years because these represent the real-world system of traffic behavior. The high cost of acquisition and the tedious and time-consuming calibration and validation of the system hinders many potential end-users from utilizing this technology. End-users, especially the local government units might not readily understand the system's output-this may create dilemmas in selecting the most effective traffic control alternative in addressing traffic congestion and accidents alleviation. Moreover,these softwares do not include practical yet economical solutions. The study's aim is to develop an expert system for decision-making factors for the use of traffic engineers in government agencies, private companies, as well as civil engineering students. The system will be able to present mitigating measures and cross-classify potential alternatives for both the alleviation of traffic congestion and the reduction of accidents in an intersection.

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This paper investigates the advantages of exclusive bus lanes by the comparison of car travel time between ordinary lane case and exclusive bus lane case. Moreover, the effects of bus lane types and bus bay priority on the travel time of each kind of vehicles are analyzed based on the simulation of bus bay priority and three cases of bus lane in a traffic system. The simulated bus lane cases include roadside exclusive bus lane case, bus priority lane case and ordinary lane case. Especially, aggregations of the bus bay priority in the case of ordinary lane can create many effects on the travel time of buses and other vehicles as well. This bus bay priority is considered as the priority of bus in merging into the main stream. Besides, a share of the number of buses that have this kind of priority in each simulation period can be quantified to vary from 0% to 100%. Finally, conclusions and suggestions concerning with bus lane types and bus bay priority are proposed.

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Lately the government has started to allow freeway motorists to operate on the Dynamic Traffic Lane (DTL) that is a temporary lane within the hard shoulder areas opened only during traffic congestion periods in urban freeways. Despite drawing safety concerns, the DTL is reported to be helpful in handling freeway congestion. This paper presents the result of investigating the efficiency impacts of the DTL in several sites. The result showed that some speed reductions were observed in the afternoon hours, but little speed variations were found in Type I. Type II use gives greater effects than the ones in Type I in South Korea, and this is believed to be caused by the fact that fundamentally Type II fits more closely to the original dynamic traffic lane concept. With Type III DTL, the average speed decreased for the most part except it increased slightly when volume reduces.

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In this paper, standard score of travel time is proposed as a new measure of travel time reliability. ETC (Electronic Toll Collection) data is firstly used to estimate and clarify the micro relationship between travel time variance and accident/incident happenings on some popular routes on the Metropolitan Expressway Co., Ltd. at Tokyo. We find that although the common travel time reliability measures such as 95percentile travel times are more sensitive to the happenings of accidents, if compared with average travel times, the difference is not that significant. On the other hand, the standard scores of travel times have a potential of being adopted as a new measure of travel time reliability since it can better distinguishes the different travel time distributions of cases with and without accidents.

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Capacity is a primary concept in the most of traffic engineering studies, however microsimulation models generally ignore this concept because these models are built on car following and lane changing theories. There are significant numbers of studies on capacity analysis based on analytical approaches including Highway Capacity Manual and the Australian Research Report. The analyses conducted using microsimulation reflected under representation of capacity however such studies are limited in numbers and scope. This paper reports an investigation conducted using AIMSUN microsimulation model to analyze the capacity and queue discharge flow rate at a signalized intersection in Auckland. The results from this model were first verified against the data collected from loop detectors and then compared with those from analytical approaches.

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Travel time is one of the most important measures for evaluating the performance of road networks. Travel time information has become increasingly important for transportation planning, route guidance as well as congestion management purpose. This paper reports a study conducted to investigate the level of congestion on arterial road networks in Auckland. Average car method was employed to collect travel time data on three major arterial routes during morning peak hours using an instrumented vehicle equipped with GPS receiver. The Level of Service (LOS) concept proposed in Highway Capacity Manual 2000 was used to determine the level of congestion on the arterial routes. The sample size required for reliable estimation of travel time was determined based on confidence interval method. The analysis results were then compared with those coming from a similar study conducted in 2004 by Transit New Zealand.

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The paper proposed a simple technique using statistical color matching to identify the stain or mark on the object at accident scene. The whole process includes scanning the photos to obtain digital images, retrieving RGB color values of the pixels sampled on the stain, converting them to HSI values, and establishing the hypothesis testing on the difference of color parameters means. A case study was conducted to identify whether stain or contaminant on a motorcycle in accident-scene photos was the bloodstain. Test results show no difference in color hue but significant distinction in saturation between the two assuming that alpha value is 0.00001. We have not sufficient evidence to support that the suspect stain is bloodstain. Obviously, the color matching technique can be used to facilitate the visual examination to identify the belonging of the stains.

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This paper attempts to provide additional insights of using a bivariate ordered probit model to simultaneously examine influential factors that affect injury severity (IS) and collision type (CT) of traffic accidents occurring on intersections of national highways in Japan. The effectiveness of the bivariate model is re-confirmed using a large-scaled traffic accident data. The corrections between error terms of IS and CT are statistically significant, implying that there are some unobserved factors that simultaneously affect IS and CT, but are not well captured in traditional accident surveys. Six types of collisions are dealt with and their influential factors are examined with respect to both primary and secondary parties. A complicated structure of influential factors is clarified, and it is expected that such complexity cannot be properly captured based on the widely applied cross-aggregation method in practice.

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