• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2006.05a
• /
• pp.95-98
• /
• 2006

Data collected by sensors in field are transmitted to the base station gathering all of data. Because sensors have to gather data in surroundings and periodically transmit data to the base station, it makes energy consumed much. In this paper, we propose the scheme that is to avoid traffic congestion with achievement of energy efficiency, so collected data is transmitted efficiently. This is to adjust transmission rate differently in case of increasing or decreasing traffic and minimize the energy consumption with setting ideal options up basic CSMA(Carrier Sense Multiple Access) protocol in each sensor. Through the simulation, we find the ideal CSMA options and apply the proposed scheme of traffic control mechanism to them, then show energy efficiency and effective traffic control mechanism.

• Asia pacific journal of information systems
• /
• v.26 no.3
• /
• pp.427-448
• /
• 2016

The stochastic phenomena of traffic network condition, such as traffic speed and density, are affected not only by exogenous traffic control but also by endogenous changes in service time during congestion. In this paper, we propose a mixed M/G/1 queuing model by introducing a condition-varying parameter of traffic congestion to reflect structural changes in the traffic network. We also develop congestion indices to evaluate network efficiency in terms of traffic flow and economic cost in traffic operating system using structure-changing queuing model, and perform scenario analysis according to various traffic network improvement policies. Empirical analysis using Korean highway traffic operating system shows that our suggested model better captures structural changes in the traffic queue. The scenario analysis also shows that occasional reversible lane operation during peak times can be more efficient and feasible than regular lane extension in Korea.

• The Journal of the Korea Contents Association
• /
• v.21 no.12
• /
• pp.190-201
• /
• 2021

The variable message sign (VMS) is equipment to improve the efficiency of traffic flow and safety of travel by providing real-time information to road users on traffic, road, weather situation, and traffic control due to construction. The information messages of the letter-based VMS taking up most of the VMS on the general national highways consist of section, travel time in sections, and road control situation. This study devised an improvement plan centered on road users, not road managers-centered existing message-based VMS through an analysis of road users' preference targeting the letter-based VMS operated in the general national highways in the Seoul Metropolitan Area. By presenting the measure for system improvement through which information on unexpected situations that road users prefer the most can be quickly and efficiently provided, this study aims to improve the efficiency of road user-centered VMS traffic information.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.6
• /
• pp.137-146
• /
• 2007

The objective of this paper is to study the establishing system of truck collaboration and to reduce traffic cost for participating transportation enterprises. The system of truck collaboration can enhance the transport efficiency and to reduce traffic cost without new investment for trucks and equipments. The type of truck collaboration should be enumerated (1) the system of head and branch base (2) the system of central terminal (3) the system of separating collection and delivery for cargo (4) the system of cooperating cargo order and truck allocation. The efficiency of truck collaboration is possible to be realized for transportation enterprises, receiver and sender of cargo.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.11 no.2
• /
• pp.59-77
• /
• 2003

Air Traffic Control Tower is one of the most important units in Airport operation. It provides services related to safe and efficient traffic flows that control aircraft on the ground maneuvering area and terminal airspace. Also It is responsible for managing of ground operators. The major objective of this study is to evaluates relative efficiency of ATC towers in Domestic airports using data envelopment analysis so that it helps the ATC authority to improve the tower efficiency, to decide the level of benchmarking target and to establish the best alternative. The results of this study are the following; First, as a result of analysis for the potential improvement, it has analysed that the common problems of each ATC tower are to increase its number of flight and to reduce its number of runway followed by airside area, the number of air traffic controller and the number of stand. Second, it has shown that the each tower in RKPC(8), RKPT(5), RKPK(l) and RKSS(l) are used as the reference set. Especially, the tower in RKPC analyzed as a relatively efficient unit is the most main target for the towers in RKTU, RKTH, RKPS and RKTY to do bench marking and to set up the strategy for improving relative efficiency of the tower. Third, tower is actually not able to control the input and output data in this study except the number of controller, so that ATC authority is recommended to improve inefficiency of the towers through handling the number of controller.

• 한국방재학회:학술대회논문집
• /
• 2007.02a
• /
• pp.468-474
• /
• 2007

Korea's road traffic has been the important role of social and economic development, and it'll be a much more important in the future. But we require a far more efficient road traffic system to solve the problem of vehicle increases. So this paper is analyzed and researched both road traffic systems and road traffic safety, and hypothesized a solution to the problem by using small town's road traffic system demands as a good example. The road traffic system should harmonize around the structure of the town, and be related to the safety, By analyzing road traffic system, we can understand how importantly the traffic system is related with safety, efficiency and overall benefits for our community.

• Journal of Korea Multimedia Society
• /
• v.17 no.6
• /
• pp.681-686
• /
• 2014

In this paper, we propose a traffic adaptive mechanism that controls the receiver's wakeup periods based on the generated traffic amounts. The proposed control mechanism is designed for military, wild animal monitoring, and forest fire surveillance applications. In these environments, a low-rate data transmission is usually required between sensor nodes. However, continuous data is generated when events occur. Therefore, legacy mechanisms are ineffective for these applications. Our control mechanism showed a better performance in energy efficiency compared to the RI-MAC owing to the elimination of the sender node's idle listening.

• Journal of Korean Society of Transportation
• /
• v.14 no.2
• /
• pp.45-58
• /
• 1996

In a large signal intersection, it is the most important to set phase sequences and phase intervals of traffic signal in order to improve the efficiency of the capacity as well as safety. These setting allows to select the best sequence of signal phase among several alternatives, and thus to rearrange the starting and ending points of the individual phase using an effective interphase periods (EIP). The EIP is a gap between previous and current traffic movements at a potential collision point in an intersection. Each of traffic movements has an equality for safety and efficiency at the balanced condition of EIP. This paper presents how to set optimally the phase sequences and intervals of traffic signal in an intersection using phase based approach. And in the second part, we applied the theory developed in the first part. In particular, a numerical example of phase base signal setting is presented using a matrix computation method in order to select the best sequence among several alternatives, and thus to rearrange the starting and ending points of the individual phase using the EIP. This method also allows to apply to optimum signal setting even in five-lag or staggered-type intersection.

• Journal of the Korean Society of Safety
• /
• v.32 no.5
• /
• pp.141-148
• /
• 2017

Over the past 30 years, the business effects of the improvement project at black spot have been decreasing since 2010, with a reduction in the amount of government spending, coupled with proposing a uniform improvement plan. In order to promote more efficient improvement projects, it is necessary to evaluate the efficiency of local governments and improve the business methods of local governments with low efficiency. However, more sophisticated efficiency analysis methods are needed. Because in previous studies have been limited to the analysis of effects before and after the project through the simple before-after analysis. For this purpose, this study analyzed the efficiency of improvement project at black spot by local governments in Gyeonggi-do using DEA to compare and analyze efficiency in various fields. As a result, Goyang, Seongnam, Paju, Hanam and Yangju showed high efficiency local governments. For local governmetns with low efficiency, the improvement projets to improve efficiency were divided into civil engineering work, structure work, pavement work, additional work and transportation work, and the appropriate construction ratios of each local government were analyzed and presented.

• International Journal of Highway Engineering
• /
• v.19 no.1
• /
• pp.81-90
• /
• 2017

PURPOSES : The goal of this study is to analyze the operational efficiencies of special roundabouts using simulated programs. METHODS : This study primarily focuses on comparing the delays and traffic flow disturbances occurring at special roundabouts. In this study, the operational efficiencies of 450 scenarios (5 roundabout types ${\times}$ traffic volumes ${\times}$ directional ratios ${\times}$ measures) are analyzed according to the corresponding delays and traffic flow disturbances using VISSIM and SSAM. RESULTS : The main results are as follows: 1) the Hamburger roundabouts are determined to yield the least common-type delays, 2) the amount of delays at Turbo and Flower roundabouts with respect to relatively increased right-turn-type delays, in addition to the amount of delays at the Left-turn slip-lane roundabout with respect to relatively increased left-turn-type delays, are found to be reduced as compared to the common-type delays. Lastly, common- and increased right-turn-type traffic flow disturbances at the Turbo roundabout and increased left-turn-type traffic flow disturbances at the Left-turn slip-lane roundabout are determined to be the most infrequent. CONCLUSIONS : This study comparatively analyzes five roundabout types: standard, Flower, Turbo, Hamburger, and Left-turn slip-lane. The effectiveness of roundabouts can increase according to given traffic volume, directional ratio, and measure of effectiveness.