• Proceedings of the KSME Conference
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• 2000.04b
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• pp.599-604
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• 2000

In order to study unsteady aerodynamic loads on high speed trains passing by each other at the speed of 350km/h, three-dimensional flow fields around trains during the crossing event are numerically simulated using the three-dimensional Euler equations. The Roe's FDS with MUSCL interpolation is employed to simulate wave phenomena properly. An efficient moving grid system based on domain decomposition techniques is developed to analyze the unsteady flow field induced by the restricted motion of a train on a rail. The numerical simulations of the trains passing by on the double-track are carried out to study the effect of the train nose-shape, the train length and the existence of tunnel when the crossing event occur. Unsteady aerodynamic loads side force and drag force-acting on the train during the crossing are numerically predicted and anlayzed. It is found that the strength of the side force mainly depends on the nose-shape, and that of drag force on tunnel existence. And it is observed that the push-pull like impulsive force successively acts on each car and acts in different directions between the neighborhood cars. The maximum change of the impulsive force reaches about 3 tons. These aerodynamic force data are absolutely necessary for the evaluation of the stability of the high speed multi-car train. The results also indicate the effectiveness of the present numerical method for the simulation of unsteady flow field induced by the bodies in the relative motion.

• Korean Journal of Ecology and Environment
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• v.38 no.spc
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• pp.67-75
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• 2005

The objectives of this study were to understand the runoff characteristics of the non-point sources originating from impervious surfaces and to assess their effect on the aquatic environment in the urban areas. The concentration of pollutants (SS, BOD, COD and T-P) except for T-N showed the highest value in runoff from road, and event mean concentration (EMC) also showed high value from road. The pollutants discharged from road showed a higher concentration in the beginning stage (0 ${\sim}$ 30%) of progressive percentage of rainfall. The contribution percentages of non-point sources by load were 44.9% for SS, 11.2% for BOD, 21.4% for COD, 11.4% for T-N and 8.1% for T-P in the total load of pollutant discharged through sewer. From our results, the road was a significant potential source that deteriorated water quality of the streams and lakes in the vicinity of the urban area during the rain period. Therefore, counter plan is required to reduce pollutant concentration on the road from non-point sources in the urban area. Also, since pollutant concentration in the beginning stage of rainfall was quite high, road cleaning seems to be one of the very useful methods to prevent inflowing of pollutants to the aquatic environment.

• Journal of the Korea Society for Simulation
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• v.15 no.1
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• pp.43-50
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• 2006

The major objective of this paper is to propose a hybrid simulation environment for autonomous UAV system by integrating the continuous-time model with discrete-event model. Proposed system is able to support high autonomous behavior by combining the planner, recognizer, and controller model to deal with the HL20 AIRPLANE model. Thus, the high level decision may be efficiently issued even upon the unexpected circumstance. The proposed system model has been successfully verified by several simulation test performed on the DEVS simulation S/W environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.3
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• pp.34-45
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• 2003

The motivation for transforming the Seoul City Hall plaza into place for pedestrians was prompted by the 2002 World cup event. This place has diverse time layers ranging from the Yi-dynasty to the present. Around city hall, diverse cultural assets and distinctive architecture are scattered. The place is a kind of melting pot that represents different times and cultures in the city. Transforming place for cars into place for citizens suggest several implications in city making policy such as high priority for pedestrians in urban design and enhancement of the public open spaces through downtown remodelling. Our plan is to propose the idea of Media plaza. One of the characteristics of Seoul now can be summarized as Media because the W industry and infrastructure are well developed in the city. ´Seoul Media Plaza´ adopts high-tech infrastructures such as RGB color post, multi box, I-Gate, etc as design materials. Three concepts of the plan are ´evolutionary plan´, ´flexible plan´, and ´participatory plan´. First, the plan will embrace the future changes of external conditions. Second, the plan should be flexible to accomodate the diverse activities in the plaza. Another special aspect of the plan is a kind of open plan. The ground surface of the plaza will be changed in its pattern and shape by citizen participation. Finally, the ´Seoul Media Plaza´ attempts to represent the spirit of Seoul and to connect the past, the present and the future while promoting citizen participation.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.61-70
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• 2005

The purpose of study was to investigate the kinematic variables of Kenmotsu motion in Parallel bars. To this study, by 3 dimensional kinematical analysis of 4 male national gymnasts participants in the 28th Athens Olympic Game in 2004, kinematic data collected using video camera. Coordinate data were smoothed by using a fourth-order Butterworth low pass digital filter with cutoff frequency of 6Hz. The conclusions were as follows. 1. In P2, because the constrained swing movement made the movement of a rising back difficult7, the movements of Reg. were performed at low position after Air phase. 2. In E5 event, for the shake of a stable handstand and applied techniques like a Belle(E-value), a Belle Piked(super E-value), a vertical velocity in E2, a horizontal velocity in E3 and a vertical velocity in E4 were necessary for high velocities. 3. In E4 event, it was appeared that for a flexible body's movement of a vertical up-flight, the large angle of the shoulder joint and the flexion & extension of the hip joint were necessary in Air phase and a long flight time and vertical displacement made Reg. movements stable at the high position.

• Journal of the Korean Society of Food Culture
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• v.30 no.1
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• pp.29-40
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• 2015

This study analyzed purchasing characteristics of local agricultural products and processed products as well as evaluated operation programs for Changnyeon festival participants. The purchasing rates of local agricultural products and processed products at this festival were 63.6% and 49.1%, respectively, and the main purchased crops were onion (42.6%) and garlic (20.7%). Drinks (43.6%) were highly purchased processed products. The recognition (95.3%) and preferences (98.4%) for Changyeong local agricultural products were high at this festival. Subjects (72.5%) responded that public relations were effective for sale at this festival, and evaluation of the operation program for the festival was $3.51{\pm}0.74$ (total score 5 points). Satisfaction with the experience event (37.7%) and exhibition event (33.6%) were high at this festival program, whereas participants gave low rates for art exhibition and sale events of local agricultural products (16.2%), cooking education (14.7%), direct education program (12.9%), and games (12.1%). This festival was an effective means of public relations, although purchase effects were not significant. This result suggests that the festival is necessary for planning a program to increase purchasing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.115-116
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• 2020

Recently, due to fires in high-rise residential and commercial buildings and apartments in Ulsan and Busan, the issue of evacuation safety in the event of a building fire is being closely watched. In the evacuation safety design for these building fires, it is important to secure evacuation routes considering the spatial characteristics of the building or the characteristics of the occupants and to take measures to protect the evacuation routes in order to ensure the safety of the occupants in the event of a fire. Although simulation is mainly used in Korea to assess the safety of evacuation, there is a big difference in that the Building Standards Act provides tools that can be calculated more than simulation in neighboring Japan. In addition to the evaluation method, which is called the "Building Law Assessment Methods" in Japan, the research team considered that it is important to know the process of evaluation in future domestic research, and investigated the contents of the evaluation process and wanted to apply it first to domestic buildings in the future.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1356-1359
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• 1996

The paper studies design of a decentralized supervisory controller with 2-level hierarchical structure for complex discrete event systems. Hierarchical structure with strict output-control-consistency(SOCC) gives a more abstract model for high-level control. The decentralized controller for a simple and abstract high-level system is designed more easily if the decentralized supervisory control problem in 2-level hierarchical structure systems(DSCP2) is solvable.

• Journal of Families and Better Life
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• v.14 no.4
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• pp.175-190
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• 1996

The purpose of this study was to investigate the relationships of resource financial events coping strategies and family financial satisfaction. The data were collected from 499 housewives in Seoul. The major findings: 1. The financial events were categorized into 6 factors. The factors were named as related to 'Family' 'Health' 'Money' 'Car & durables' 'Job', 'Housing'. Among these events respondents who had exprienced housing-related event reported the highest level of financial stress. 2. The coping strategies were categorized into 4 factors: 'Delaying payment' 'Borrowing' 'Economical purchasing' 'Using Worth' The most frequently used 'Economic purchasing' strategy. 3. Various coping strategies were differently used depending on financial events. For example the housewives used 'Economical purchasing' strategy to cope with family-related events and used 'Borrowing' strategy to housing-related events. Housewives who had less income and less net-worth used ' Economic purchasi g' strategy. 4. Job-related events were negatively effect to family financial satisfaction but car & durables-related event were positively effect to family financial satisfaction. Housewive who the more income and the less age had the high satisfaction. 'Delaying payment' and 'Economical purchasing' strategies were negatively related to family financial satisfaction.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.882-885
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• 2003

In this paper, we describe a haptic jacket and wheel as a haptic interface to enhance VR game realism. Building upon the VR game system using this devices, our haptic interface technique allows the user to intuitive interact on game contents, and then to sense the game event properties such as walking, attacking, driving and fire in a natural way. In addition, we extended the initial haptic model to support haptic decoration and dynamic interactions due to the added game event in a real time display. An application example presented here is a VR Dino-Attack game. This game supports interactions among dynamic and our intuitive haptic interface. Modeling physic interactions involves precise collision detection, real-time force computation, and high control-loop bandwidth.