• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.11-21
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• 2011

This study intends to construct scenic byway database and to examine and suggest social experiment of scenic byway. As basis work for the experiment of the scenic byway, we build database by using ITS standard node link management system. The DB includes scenic byway routes of Korea and Japan. The analyses show that the scenic byway in both nations consists of roads, reservation, road sign, vehicle number plate, and it was found that infrastructure and system are inadequate for scenic byway. These experiment can be effectively used for scenic byway in Korea and Japan as the basis data. The results of this experiment will be useful for plan and develop a scenic byway.

• Journal of KIISE
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• v.42 no.10
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• pp.1231-1238
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• 2015

Traffic light rules are one among the most common and important safety rules as the directly correlate with the safety of pedestrians. Consequently, an algorithm is required to cause an automated (or semi-automated) vehicle to observe traffic light signals. We present a novel, artificial potential function to guide an automated vehicle through traffic lights. Our function consists of three potential function components representing the three traffic light colors: green, yellow, and red. The traffic light potential function smoothly changes an artificial potential field using the elapsed time for the current light and light conversion. Our traffic light potential function is combined with other potential functions to guide vehicles' movement and constructs the final artificial potential field. Using various simulations, we found or method successfully guided the vehicle to observe traffic lights while behaving like human-controlled cars.

• New & Renewable Energy
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• v.4 no.4
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• pp.30-36
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• 2008

The possibility of whether the induced wind from a vehicle traveling on highway can be used in wind power generation has been verified through computational flow analysis. The bus which is presumed to accompany relatively strong and wide range of induced wind compared to passenger vehicles because of its wide frontal area has been set as the subject of research. In order to ensure the reliability of research, the flow analysis surrounding the bus on a flat road where median strip is not installed has been compared with a preceding research while the validity of grid system and interpretation method used in this research have been assured by a qualitative method. In case of the median strip type wind power generator system, because it has been verified that a strong streamwise wind speed (5 m/s) is derived from the contraction effect of flow passage between the bus and the median strip while maintaining a relatively consistent upwind wind speed (1.4 m/s) in vertical direction in the wake area after the bus passes by although the change of wind speed is intense, it was decided as having some possibility of wind power generation. In case of the traffic sign panel type wind power generator system installed at the upper top of highway, because the wind speed of 2 m/s level has been derived for a limited time only at a section equal to the length of the bus and a faint induced wind speed less than 0.5 m/s was shown at other regions, it was decided as having almost no possibility of wind power generation.

• Journal of the Korean Society of Safety
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• v.27 no.6
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• pp.185-191
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• 2012

Rear collisions to expressway work trucks result many casualties these days. But, currently, no special measure are being taken except deploying sign trucks behind the working trucks. In the U.S and Europe, trucks with TMA(Truck Mounted Attenuator) are being deployed behind the working truck, which is regarded as the standard method for work area safety, thereby reducing the fatality rates and property damage tremendously. Also, standard for the performance of TMA are established and TMA can be used in the field only when it satisfies the standard. In Korea, neither the standard for nor any guide to the TMA exists. In the situation some manufacturer developed TMA without proper performance evaluation and marketed limited number of TMAs in the field. In the study, NCHRP350, which is the performance standard of expressway safety features of U.S. and materials related to the TMA standard in Europe have been reviewed to establish the Korean performance criteria. Based on the review, and incorporating existing Korean standard for crash cushions, domestic standard for TMA has been proposed and applied in developing Korean TMA and crash tested it to verify the performance. The original design developed was crash tested and modified. The newly proposed design was studied using impact simulation program several times. Modifications were made after each simulation and prototype was built and crash tested as per the newly established TMA performance criteria.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.5
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• pp.959-967
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• 1988

In this paper, 2-DOF vehicle suspension system with a semiactive on-off damper was studied for improving the ride comfort. It is known that a nonlinear hydraulic damper, which generates force proportional to the square of the relative velocity, can describe the actual fluid resisting type damper more properly than the traditional viscous damping model. On the other hand, hydraulic damper adoption in analysis makes the system nonlinear and causes difficulties to get the system response. In this work, time domain direct integration method was used to calculate system displacement and acceleration. first of all, the response of the suspension system experiencing a given road profile was optimized by Lagrangian multiplier method within the range of given damping coefficients. The appropriate on-loaf damping values were obtained by averaging the already calculated optimum damping coefficients from Lagrangian techniques. The criterion to control the on-off mechanism was determined by examining the suspension efficiency. It was found that the best out of practically applicable criteria is following the sign (positive and negative) of the multiplication of relative displacement and velocity. Judging from the theoretical calculations, it was proved that the semiactive on-off damper can increase suspension efficiency as much as 8-11% in object function.

• Journal of Chest Surgery
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• v.56 no.6
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• pp.431-434
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• 2023

Background: The first 3 ribs are anatomically well-protected, shielded by the large thoracic muscles, the shoulder girdle, and the arm. A significant force is required to fracture these ribs; thus, such fractures suggest a high-energy trauma and are associated with injuries to vital organs of the thorax, such as the aorta, the heart, the lungs and the great vessels. Methods: A retrospective analysis was conducted over a 10-year period at a single hospital. The study assessed patients with fractures of the second rib, including their concurrent injuries and the overall severity of their trauma. Results: Among the 76 patients included in the study, the average age was 47.35 years, 81.5% were men, and 19.5% were women. Thirteen patients (17.1%) survived their injuries. The most common causes of injury were road traffic accidents (63%) and pedestrian injuries (22%). The patients who did not survive sustained injuries to an average of 5 additional organs, while survivors had injuries to an average of 2.07 additional organs. Left rib fractures were the most frequently observed (46%). The most serious concurrent injuries reported were to the aorta (5.26%), heart (10.52%), lung (52.36%), head (57.89%), liver (30.2%), spleen (26.31%), and kidney (17.1%). Conclusion: As indicators of serious injury to vital endothoracic organs, isolated fractures of the second rib should be considered equal to first rib fractures in clinical importance.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.375-382
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• 2020

As the 4th Industrial Revolution era in worldwide, interest in autonomous vehicles is increasing. but due to recent safety issues such as pedestrian accidents and car accidents, as a technical model for this, the demand for 3D HD maps (High Definition maps) is increasing in including lanes, road markings, road information, traffic lights and traffic signs etc. However, since some complementary points have been continuously raised according to demand, It is necessary to collect the opinions of institutions and companies utilizing HD maps and to improve HD maps. This study was conducted by utilizing the results of the contest for usability verification of HD Maps hosted by the National Geographic Information Institute and organized by the Spatial Information Industry Promotion Institute. For this study, we researched HD maps' layers and codes for HD maps object usability to improve HD maps, constructed HD maps object usability items accordingly, and contested usability verification of HD maps according to the items The contestants conducted verification and analyzed the results. As a result, the most frequently used code for each layer was the flat intersection, and the code showing the highest usage rate was a safety sign. In addition, the use rate of the sub-section and height obstacles was 16.67% and 8.88%, respectively, showing a low ratio. In order to utilize HD maps in the future, this study is expected to require research to continuously collect opinions from customers and improve data objects and data models that are actually needed by customers.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.1
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• pp.55-69
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• 2017

Recently, the IoT (Internet of Things) environment is being developed rapidly through network which is linked to intellectual objects. Through the IoT, it is possible for human to intercommunicate with objects and objects to objects. Also, the IoT provides artificial intelligent service mixed with knowledge of situational awareness. One of the industries based on the IoT is a car industry. Nowadays, a self-driving vehicle which is not only fuel-efficient, smooth for traffic, but also puts top priority on eventual safety for humans became the most important conversation topic. Since several years ago, a research on the recognition of the surrounding environment for self-driving vehicles using sensors, lidar, camera, and radar techniques has been progressed actively. Currently, based on the WAVE (Wireless Access in Vehicular Environment), the research is being boosted by forming networking between vehicles, vehicle and infrastructures. In this paper, a research on the recognition of a traffic signs on highway was processed as a part of the awareness of the surrounding environment for self-driving vehicles. Through the traffic signs which have features of fixed standard and installation location, we provided a learning theory and a corresponding results of experiment about the way that a vehicle is aware of traffic signs and additional informations on it.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.101-113
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• 2008

VMS are installed in many Korean highways in oder to give drivers informations such as travel time to destination, congestion and Incident situation. However, some guidelines for install VMS are restricted in only geometric factors although human factors considering driver behavior are very important to affect the VMS installation. Therefore, this paper are focusing on developing and verifying the discriminant model for VMS installation considering human factors. As a result, following outputs are obtained ; (1) developing the discriminant model using human factors of driving simulation experiments in oder to predict driver reading VMS messages safely detour highway. (2) proving that driving experiences in highway, personal driving history, vehicle speed orderly affects VMS installation (3) verifying predictability of developed model by comparing the real values with predicted values. (4) suggesting that VMS should be installed off 3.2Km from the I.C. of rural highway.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.223-233
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• 2014

This study empirically analyzes the relationships among the road and traffic experts' personal characteristics, the driving behavior and factors being expected to have an effect on the satisfaction about roundabout operation. The factors are drawn and grouped through the principle component analysis to clarify driving environment satisfaction on roundabout operation. Each group is named as personal attribute, driving behavior attribute, and satisfaction. After the variables are refined by confirmatory factor analysis, satisfaction model is developed with personal attribute and driving behavior attributes as exogenous variables and roundabout driving awareness and emotion attributes as endogenous variables. As a result, driving satisfaction of roundabout operation is directly influenced by delay reduction, safety improvement, capacity increase, sight improvement, severity accident reduction, and bicycle convenience and indirectly gender, age, driving time, and driving experience. Law obeyance, driving concession, traffic sign obeyance, and interposition do not statistically shows significant on satisfaction. As a result of Analytical Hierarchy Process (AHP), the turning radius of geometry and the driving behavior are important elements for roundabout safety.