• Journal of Industrial Technology
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• v.21 no.A
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• pp.231-240
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• 2001

U-turn and P-turn as well as left-turn restriction exist in real traffic network. the optimal route should be selected for considering these using shortest path algorithms. But, the traditional algorithms have some limitations to use for considering there. The objective of this paper is to modify Dijkstra algorithm in order to find the optimal path in real traffic network. The continuous three nodes are used to check turn-restrictions and exclude these from and optimal path. A virtual connection is used to consider U-turn and P-turn.

• Journal of Industrial Technology
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• v.21 no.A
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• pp.241-249
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• 2001

The objective of this paper is to develop the optimal path algorithm for dynamic route guidance system in advanced traveler information system (ATIS). The travel time is forecasted in each path between network nodes. Floyd-Warshall algorithm is used to find the optimal route based on this forecasted travel time in dynamic traffic network. This algorithm is modified to apply the real traffic network that has left-turn restriction, U-turn, and P-turn. A big value is assigned to one of arcs in turn restriction and a virtual node is used to consider U-turn and P-turn for Floyd-Warshall algorithm.

• Journal of Industrial Technology
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• v.22 no.A
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• pp.73-82
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• 2002

It is difficult to find the shortest paths using existing algorithms (Dijkstra, Floyd-Warshall algorithm, and etc) in high complex and large size real traffic networks The objective of this paper is to develop an evolution program to find the multiple shortest paths within reasonable time in these networks including turn-restrictions, U-turns, and etc.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.663-668
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• 2010

In driving a car, turns such as left turns, right turns, or u-turns, make the speed of the car decrease considerably. A more straight path, therefore, is probably faster to arrive at the destination than zig-zag path with same distance. In this paper, we have newly proposed the turn heuristic to make more straight path. The path navigation algorithm with turn heuristic(called as TA* algorithm) could enhance the straightness of a path by putting the turned-edges to the turn cost. It requires higher cost to use TA* algorithm than traditional A* algorithm because the straight-edge first searching have increased the search space. We have improved the TA* algorithm into the variable TA* algorithm(called as VTA* algorithm) which adopt the turn-heuristic during the a portion of the whole path.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.179-182
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• 2008

It needs to consider of turns during a path-finding on real road network. Because a car is delayed by waiting a traffic signal and decreasing speed when drived in a turn road such as cross road and slip road. If a straightness of a path is increased, a real cost of traveling should be able to decrease. An older method, the algorithm with Turn Heuristic, considered of this case. The algorithm, that differently gave weights to left, right and U-turns, improved a straightness of a path, but increased a cost of exploring. In this paper, we propose a improved Turn Heuristic Algorithm. Proposed algorithm uses Dynamic Turn Heuristic. It is able to more decrease a cost of exploring than older method by using the Turn Heuristic in a part of path-finding.

• Journal of Intelligence and Information Systems
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• v.21 no.2
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• pp.19-47
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• 2015

In this era of knowledge economy, a variety of virtual communities are proliferating for the purpose of knowledge creation and utilization. Since the voluntary contributions of members are the essential source of knowledge, member turnover can have significant implications on the survival and success of virtual communities. However, there is a dearth of research on the effect of membership turnover and even the method of measurement for membership turnover is left unclear in virtual communities. In a traditional context, membership turnover is calculated as the ratio of the number of departing members to the average number of members for a given time period. In virtual communities, while the influx of newcomers can be clearly measured, the magnitude of departure is elusive since explicit withdrawals are seldom executed. In addition, there doesn't exist a common way to determine the average number of community members who return and contribute intermittently at will. This study initially examines the limitations in applying the concept of traditional turnover to virtual communities, and proposes five membership fluidity measures based on a preliminary analysis of editing behaviors of 2,978 featured articles in English Wikipedia. Subsequently, this work investigates the relationships between three selected membership fluidity measures and group collaboration performance, reflecting a moderating effect dependent on work characteristic. We obtained the following results: First, membership turnover relates to collaboration efficiency in a right-shortened U-shaped manner, with a moderating effect from work characteristic; given the same turnover rate, the promotion likelihood for a more professional task is lower than that for a less professional task, and the likelihood difference diminishes as the turnover rate increases. Second, contribution period relates to collaboration efficiency in a left-shortened U-shaped manner, with a moderating effect from work characteristic; the marginal performance change per unit change of contribution period is greater for a less professional task. Third, the number of new participants per month relates to collaboration efficiency in a left-shortened reversed U-shaped manner, for which the moderating effect from work characteristic appears to be insignificant.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.366-367
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• 2011

대화면 PDP 서스테인 파워 모듈을 위한 고효율 펄스폭 변조 컨버터가 본 논문에서 소개된다. 제안된 컨버터는 일차측에서 병렬로 연결되고, 위상 변조 방식으로 구동되는 두 개의 하프브릿지 컨버터로 구성되어 있다. 그들의 변압기들은 이차측에서 직렬로 연결된다. 제안된 컨버터에서 모든 스위치들은 그 전부하 구간동안 ZVS를 가지고 턴 온되며, 동시에 그 ZVS 범위를 확장하기 위해 추가된 전류에 의한 도통 손실을 최소화 할 수 있는 장점을 갖는다. 또한 그 변압기의 턴 비가 비교되는 컨버터들에 비해 유리하게 설계될 수 있어 일차측 도통 손실을 개선할 수 있는 장점도 갖는다. 낮은 프로파일 설계 또한 두개의 변압기의 사용으로 달성된다. 제안된 컨버터의 성능은 80인치 PDP 서스테인 파워 모듈의 스펙으로 구현된 프로토타입 컨버터들부터 검증된다.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.185-186
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• 2014

출력 인덕터를 갖는 다양한 하프-브릿지 컨버터들은 높은 출력 전류를 갖는 medium-power에서 좋은 성능을 갖는다. 하지만, 그것들은 공통적으로 출력 인덕터에 의해 발생하는 스위치 턴-오프 손실과 스너버 손실로 인하여 낮은 경 부하 효율을 나타낸다. 이러한 기존의 하프-브릿지 컨버터들의 문제점들을 보완하기 위하여, 본 논문에서는 하나의 추가적인 스위치와 커패시터를 2차 측에 삽입하는 새로운 하프-브릿지 컨버터를 제안한다. 제안 된 회로는 경 부하 시에 추가적인 스위치를 끔으로써 below 동작을 갖는 하프-브릿지 LLC 컨버터로 동작하기 때문에, 턴-오프 손실과 스너버 손실을 줄일 수 있다. 또한, 넓은 영전압 스위칭 범위를 갖기 때문에 높은 경 부하 효율을 달성할 수 있다.

• Journal of Agricultural Extension & Community Development
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• v.7 no.1
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• pp.137-153
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• 2000

The purpose of this study was to develop long and short-run educational programs for u-turn farmers based on their need assesment. This study was conducted by review of literature and surveys. Subjects of this surveys were 310 participants of agricultural training programs developed by the Rural Development Administration for u-turn farmers in 1997 and 1998. According to major findings, many participants were faced with problems such as financial shortage, deficiency of farming skills, difficulty of marketing, new neighbours unfavourable gazing and farm labour shortage. These problems could be classified into the problems at their preparing stage and the problems of adjusting stage in their farms. And also the participants suggested that educational programs for them contain knowledge based teaching and technical practices with focus on their problems solving. With their suggestion various knowledge and technical modules were selected. Using these module several kinds of long and short-run educational programs could be developed.

• The Journal of the Convergence on Culture Technology
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• v.3 no.4
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• pp.101-106
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• 2017

This paper investigates how news media frame news editorials to deliver their subjective ideological stance through news discourse related with two candidates in 2016 U.S presidential election. For this purpose, 13 editorials were chosen and analyzed which appeared on the New York Time for the period from Sept. 1 to Sept. 30, almost two months prior to the election, giving special attention to the headlines of those editorials and the expressive linguistic forms in the selected two articles, based on the two theoretical frameworks-van Dijk' (1996)'s ideological square and Martin and White (2005)'s Appraisal Theory. The results are as follows: (1) editorials clearly supported Hillary Clinton; (2) following the appraisal theory, the category of 'feeling' was applied in expressing the preference for Hillary, whereas the strategy of judgment for Trump, where the strategy of 'emphasis' from the ideological framework were used for both candidates.