• Tunnel and Underground Space
• /
• v.9 no.4
• /
• pp.306-314
• /
• 1999

In underground spaces including nuclear waste repository, prediction of air quantity, temperature/humidity and pollutant concentration is utmost important for space construction and management during the normal state as well as for determining the measures in emergency cases such as underground fires. This study aims at developing a model for underground space environment which has capabilities to take into account the effects of autocompression for the natural ventilation head calculation, to find the optimal location and size of fans and regulators, to predict the temperature and humidity by calculating the convective heat transfer coefficient and the sensible and latent heat transfer rates, and to estimate the pollutant levels throughout the network. The temperature/humidity prediction model was applied to a military storage underground space and the relative differences of dry and wet temperatures were 1.5 ~ 2.9% and 0.6 ~ 6.1%, respectively. The convection-based pollutant transport model was applied to two different vehicle tunnels. Coefficients of turbulent diffusion due to the atmospheric turbulence were found to be 9.78 and 17.35$m^2$/s, but measurements of smoke and CO concentrations in a tunnel with high traffic density and under operation of ventilation equipment showed relative differences of 5.88 and 6.62% compared with estimates from the convection-based model. These findings indicate convection is the governing mechanism for pollutant diffusion in most of the tunnel-type spaces.

• International Journal of Highway Engineering
• /
• v.18 no.3
• /
• pp.47-57
• /
• 2016

PURPOSES : This study aims to examine the differences between the existing traffic demand forecasting method and the traffic demand forecasting method considering future regional development plans and new road construction and expansion plans using a four-step traffic demand forecast for a more objective and sophisticated national highway maintenance. This study ultimately aims to present future pavement deterioration and budget forecasting planning based on the examination. METHODS : This study used the latest data offered by the Korea Transport Data Base (KTDB) as the basic data for demand forecast. The analysis scope was set using the Daejeon Metropolitan City's O/D and network data. This study used a traffic demand program called TransCad, and performed a traffic assignment by vehicle type through the application of a user equilibrium-based multi-class assignment technique. This study forecasted future traffic demand by verifying whether or not a realistic traffic pattern was expressed similarly by undertaking a calibration process. This study performed a life cycle cost analysis based on traffic using the forecasted future demand or existing past pattern, or by assuming the constant traffic demand. The maintenance criteria were decided according to equivalent single axle loads (ESAL). The maintenance period in the concerned section was calculated in this study. This study also computed the maintenance costs using a construction method by applying the maintenance criteria considering the ESAL. The road user costs were calculated by using the user cost calculation logic applied to the Korean Pavement Management System, which is the existing study outcome. RESULTS : This study ascertained that the increase and decrease of traffic occurred in the concerned section according to the future development plans. Furthermore, there were differences from demand forecasting that did not consider the development plans. Realistic and accurate demand forecasting supported an optimized decision making that efficiently assigns maintenance costs, and can be used as very important basic information for maintenance decision making. CONCLUSIONS : Therefore, decision making for a more efficient and sophisticated road management than the method assuming future traffic can be expected to be the same as the existing pattern or steady traffic demand. The reflection of a reliable forecasting of the future traffic demand to life cycle cost analysis (LCCA) can be a very vital factor because many studies are generally performed without considering the future traffic demand or with an analysis through setting a scenario upon LCCA within a pavement management system.

• The Journal of the Korea Contents Association
• /
• v.20 no.10
• /
• pp.190-198
• /
• 2020

The development in smartphone technology has brought convenience to the life of the mankind, but an excessive use of smartphones sometimes causes various accidents. This research tried to propose an application service 'Smombie Safe Go' UI(User Interface) that allows the prevention of such accident while using smartphones when walking. For this, after research and user observations, produced walker journey maps and derived necessary main functions needed for safety, and the result showed that transparent interface, obstacle location alert, warning of dangers functions were necessary. To make the contents of the service more detailed, hazardous situations faced during smartphone use when walking were classified into 3 situations : 1. Obstacle appearing in front, 2. traffic lights on crosswalks 3. No traffic lights on crosswalks. Scenarios by hazardous situation were written, and the flow and UI of the app service that warns its users in each situation of hazards were designed. it is predicted that 'Smombie Safe Go' may be possible to be utilized as an app service that provides a safe walking experience for not only regular pedestrians but also the blind population.

• Journal of Korean Society of Rural Planning
• /
• v.21 no.2
• /
• pp.11-21
• /
• 2015

This study carried out evaluation of vulnerability in accessability and functionality using road network that was extracted from Intelligent Transportation System(ITS) and digital map. It was built in order to figure out accessability that locational data which include community center, public facilities, medical facilities and highway IC. The method for grasping functionality are Digital Elevation Model(DEM) and land slide hazard map provided by Korea Forest Service. The evaluation criteria for figure out accessability was set to related comparison of average time in urban area. Functionality value was calculated by the possibility of backing the vehicle possibility of snowfall and landslides. At last, this research computed weighting value through Analytic Hierarchy Process (AHP), calculated a vulnerable score. As the result, the accessability of rural village came out that would spend more time by 1.4 to 3.2 times in comparison with urban area. Even though, vulnerability of the road by a snowfall was estimated that more than 50% satisfies the first class, however, it show up that the road were still vulnerable due snowing because over the 14% of the road being evaluated the fifth class. The functionality has been satisfied most of the road, however, It was vulnerable around Lake Daechung and Piban-ryung, Yumti-jae, Suriti-jae where on the way Boeun. Also, the fifth class road are about 35 km away from the city hall on distance, take an hour to an hour and a half. The fourth class road are about 25 km away from the city hall on distance, take 25 min to an hour. The other class of the road take in 30 min from the city hall or aren't affected of weather and have been analyzed that a density of road is high. In A result that compare between distribution and a housing density came out different the southern and the eastern area, so this result could be suggested quantitative data for possibility of development.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.3
• /
• pp.48-58
• /
• 2009

Geo-graphical routing protocols as GPSR are known to be very suitable and useful for vehicular ad-hoc networks. However, a corresponding node can include some stale neighbor nodes being out of a transmission range, and the stale nodes are pone to get a high priority to be a next relay node in the greedy mode. In addition, some useful redundant information can be eliminated during planarization in the recovery mode. This paper deals with a new recovery mode, the Greedy Border Superiority Routing(GBSR), along with an Adaptive Neighbor list Management(ANM) scheme. Each node can easily treat stale nodes on its neighbor list by means of comparing previous and current Position of a neighbor. When a node meets the local maximum, it makes use of a border superior graph to recover from it. This approach improve the packet delivery ratio while it decreases the time to recover from the local maximum. We evaluate the performance of the proposed methods using a network simulator. The results shown that the proposed protocol reveals much better performance than GPSR protocol. Please Put the of paper here.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.9 no.3
• /
• pp.12-19
• /
• 2010

In road network, especially in urban area, inefficiency of travel time is caused by signal control and turn maneuver at intersection and this inefficiency has substantial effects on travel time. When searching for the shortest path, this inefficiency which is caused by turn maneuver must be considered. Therefore, travel time, vehicle volume and delay for each link were calculated by using simulation package, PARAMICS V5.2 for adaptation of turn penalty at 16 intersections of Gangnam-gu. Turn penalty was calculated respectively for each intersection. Within the same intersection, turn penalty differs by each approaching road and turn direction so the delay was calculated for each approaching road and turn direction. Shortest path dealing with 16 intersections searched by Dijkstra algorithm using travel time as cost, considering random turn penalty, and algorithm considering calculated turn penalty was compared and analyzed. The result shows that by considering turn penalty searching the shortest path can decrease the travel time can be decreased. Also, searching the shortest path which considers turn penalty can represent reality appropriately and the shortest path considering turn penalty can be utilized as an alternative.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.12 no.3
• /
• pp.19-28
• /
• 2013

This study evaluated the quantitative effects of the deployment of semi-actuated signal systems using field data. For this, a semi-actuted signal system was deployed in the regional roadway network extensively. This paper investigated an operating strategy of semi-actuated signal systems for field application, and implemented the functional strategy into the standard signal controller. The performance was evaluated using three measures of effectiveness such as traffic volume, travel time, and the number of delayed vehicle. From the analysis results, traffic volume increased about 9.4% and 11.3% for morning and evening peak periods, respectively. The average travel time was reduced about 6.3% and 7.8% during morning and evening peak periods, respectively because of the expansion of bandwidths for major streets. In addition, the number of delayed vehicles was reduced about 36.4% and 23.9% for morning and evening peak periods, respectively. It is expected that the effectiveness of signal control system can be improved by incorporating a properly designed semi-actuated signal system in regional roadways with directional demand variation.

• The Korean Journal of Emergency Medical Services
• /
• v.6 no.1
• /
• pp.103-128
• /
• 2002

As a result of trying the various manufacturing methods considering the reality of manpower and equipments with this manual, the following standardized procedures and contents can be suggested. (1) Since tools presenting Rock-Drill data must formalize the order of explanation although explainers are different, it will be valid that it is configured by existing power point method rather than by web document type. Composition of contents are selected on the basis of defence card and survey and then 8 items including initial screen, peripheral conditions, mobilization route, general conditions, use and structure by floor, department of vehicle consideration in activities and end screen are included. (2) Making methods and cautions of data included and used in power point are as follows ; - It was most effective that objects of fire fighting and location of neighboring fire fighting water were expressed by electronic map and drawing of inner building was made by scanning it after paining general architecture drawing(plan by each floor) rather than using drawing tools of EXCEL program or CAD drawing. And it was helpful to simplify contents of architecture drawing to wall, stairs and gate in understanding them. - Photographing of video data should be taken to show available fire fighting facilities in fire, use of planned space and the whole inner structure of each floor from the inside of fire fighting buildings and to display play time between 10 sec. and 1 min, for obstacles to distance from adjacent buildings or passage of special vehicles and fire fighting water from the outside of the building. - File format of video data taken in this way is most suitable to use wmv(window media video) or asf(advanced streaming format) type in consideration of time required for export, screen quality, file capacity and play type in Rock-Drill through network. - Still screen(photo) is more effective to express the department of fire fighting vehicles or other equipments than using video. (3) In configuration work of power point, hyper link was used most and configured to see any part at any situation like web document and then uniformity of presentation order of power point was complemented. (4) In case of sales facilities with the area of $35.557m^2$, the time of 22 hours and 30 minutes for five days was taken with five persons. Therefore, when eight-hour works a day were calculated, the whole process of video work for Rock-Drill can be finished with three day works.

• Journal of Broadcast Engineering
• /
• v.16 no.2
• /
• pp.350-359
• /
• 2011

Fast developments of broadcasting technologies since 1990s enabled not only High Definition Television service providing high quality audiovisual contents at home but also mobile broadcasting service providing audiovisual contents to high speed moving vehicle. Terrestrial Digital Multimedia Broadcasting (T-DMB) is one of the technologies developed for mobile broadcasting service, which has been successfully commercialized. One of the major technical breakthroughs achieved by T-DMB in addition to robust vehicular reception is an adoption of framework based on MPEG-4 System. It naturally enables integrated interactive data services by using Binary Format for Scene (BIFS) technology for scene description and representation of graphics object and Object Descriptor Framework representing multimedia service components as objects. T-DMB interactive data service has two fundamental limitations. Firstly, graphic data for interactive service should be always overlaid on top of a video not to be rendered out of it. Secondly, data for interactive service is only received by broadcasting channel. These limitations were considered as general in broadcasting systems. However, they are being considered as hard limitations for personalized data services using location information and user characteristics which are becoming widely used for data services of smart devices in these days. In this paper, the architecture of T-DMB hybrid data service is proposed which is utilizing broadcasting network, wireless internet and local storage for delivering BIFS data to overcome these limitations. This paper also presents hybrid BIFS technology to implement T-DMB hybrid data service while maintaining backward compatibility with legacy T-DMB players.

• Korean Security Journal
• /
• no.39
• /
• pp.269-294
• /
• 2014

Korea is concerned with information security industry due to recent leak-out private information of 3 card companies. Executives are aware of damage from breach of security such as personal data spill, is more dangerous than any other financial risks. The information security industry, which was limited in physical security and network security formerly, is evolving into convergence security of public and facility security industry. The field of interest has also been changed into security of smart phone and intelligence image recently, from firewall or Anti-virus. The convergence security is originally about access control of facility, but recently its demand has been increased mostly by public institutions and major companies. The scope of the industry also varies from finance, education, distribution, national defense, medical care to automobile industry. The market of convergence security has been expanded and new various products and services of security of intelligent vehicle, 'U' healthcare, finance, smart grid and key industries are also developed. It is required to create and enhance of new curriculum and cultivate human resources for the development of knowledge information security industry. Raising standard of education and security consciousness of the nation is also necessary to strengthen the global competitiveness.