• 대한기계학회논문집
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• 제15권1호
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• pp.241-251
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• 1991

본 연구에서는 이런 점들을 고려, 난류유동장 내의 실제 입자운동을 좀더 사 실에 가깝도록 해석할 수 있는 모델을 제시하여 아직 실험에 의존하고 있는 관계분야 에 그 이론적 응용범위를 넓히는데 그 목적을 두었따. 본 연구의 목적상 입자가 존 재하는 난류장의 통계적 특성은 이미 알고 있는 것으로 가장하였으며 유체 내의 입자 농도가 충분히 낮고 입자의 크기가 충분히 작아서 입자가 유동장에 미치는 영향은 무 시할 수 있다고 간주하였다.

• 한국도로학회논문집
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• 제15권3호
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• pp.177-189
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• 2013

PURPOSES: This study aims to suggest a proper left-turn treatment method for the bicycle traffic flow at four-legged intersections. METHODS: Four types of crossing methods are proposed and analyzed : (1) indirect left turn, (2) direct left turn, (3) direct left turn on a Bike Box, and (4) direct left turn on bike left turn lane. The VISSIM simulation tests were conducted based on forty-eight operation scenarios prepared by varying vehicle and bicycle traffic volumes. RESULTS : The results from the four-legged signalized intersections suggest that (1) the indirect left turn is appropriate when vehicle demand is high, (2) the direct left turn is efficient on most traffic situation but the safety is a concern, (3) the direct left turn on a Bike Box is appropriate when bicycle demand is high while vehicle demand is not, and (4) the direct left turn on a bike left turn lane is appropriate when both vehicle and bicycle demand are low. CONCLUSIONS : The direct left turn of bicycle provides more efficiency than the indirect left turn at the four-legged intersections but to apply the methods and to study more, advanced evaluation methods, related law, and insurance programs are needed.

• 대한교통학회지
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• 제1권1호
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• pp.56-63
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• 1983

Intersection control has dual-purposes; increasing capacity and reducing delay. The primary concern of efficient intersection control under oversaturated condition as in Korea is to increase capacity. Prevailing intersection operation technique permits thru traffic to utilize left turn lane, because the intersection without left turn pocket has left turn signal interval. In this situation, it seems not to be valid to calculate capacity, delay, and signal timings by conventional methods. By critical lane technique, capacity increases as cycle length increases. However, when thru traffic utilize LT lane, the capacity varies according to LT volume, LT interval as well as cycle length, which implies that specific cycle length and LT interval exist to maximize capacity for given LT volume. The study is designed is designed to calculate utilization factors of LT lane for thru traffic and capacities, and identify signal timings to yield maximum capacity. The experimental design involved has 3 variables; 1)LT volumes at each approach(20-300 vph), 2)cycle lengths (60-220 sec), and 3)LT intervals(2.6-42 sec) for one scenario of isolated intersection crossing two 6-lanes streets. For LT volume of 50-150 vph, capacity calculated by using the utilization factor is about 25% higher than that by critical lane method. The range of optimum cycle length to yield maximum capapcity for LT volume less than 120 vph is 140-180 sec, and increases as LT volume increases. The optimum LT interval to yield maximum capacity is longer than the intrval necessary to accommodate LT volume at saturation flow rate.

• 건축역사연구
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• 제25권1호
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• pp.7-21
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• 2016

The purpose of this paper is to study on the characteristic of site planning of Hadrian's villa. The whole site planning of Hadrian's villa can be divided by different characteristic four groups(I-IV). It is analysed to the whole site plan of such huge complex and the site planning of partial each group which is organically connected each other. The results of this study are as follows: 1. Hadrian's villa was arranged in adapt to natural condition according to a gentle inclination by topography and terrain of the whole site which many different buildings are oriented towards natural landscape of the site and the site surroundings. 2. The site planning of Hadrian's villa is composed of dividing into four groups as plan segmentalized through various land use plan, considering for territory of functional aspect and direction of axis formed by situation and direction of topography and terrain. 3. The concept of site planning to buildings of Hadrian's villa is composed through each other connection; the first, meeting, crossing and merging with each other from arrangement by several axises, the second, change of direction with as the center a part of corner of buildings and the third, facing or inserting system to side and side, side and a part of corner of building.

• 한국철도학회논문집
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• 제7권3호
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• pp.193-199
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• 2004

Numerical analysis of aerodynamic characteristics was differently performed according to the running situation of the Korean Tilting Train eXpress(TTX) that would be introduced for an improvement in efficiency of the used railroad track. Fluent 6.0 was used for the analysis of Non-tilting case, Tilting case and Passing-by case with the model of TTX. As a result, the aerodynamic drag had little difference between Tilting and Non-tilting case. However, pressure contour under the train of Tilting case was not symmetry because the gap between a train and the ground was different at both sides. In Passing-by case attraction and counterattraction occurred alternately and affected to the opposite train. When two trains were side by side, the maximum attraction was generated especially. Through an analysis of pressure wave in tunnel a large variation of pressure was generated by the bluff nose of TTX. The results in this study would be good data for the aerodynamic characteristic on TTX and provide important information to judgment of running safety.

• 융합보안논문지
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• 제9권1호
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• pp.11-17
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• 2009

본 연구에서는 영상센서를 이용한 상황인식 기반의 컴퓨팅 기술이 혼합된, 스쿨존 안전 관리 시스템을 제안한다. 영상센서를 통한 객체 추출과 상황 인식 기술의 조합을 통하여, 초등학교 주위에서 발생할 수 있는 여러 상황 중 초등학생의 유괴나 사고 등을 인식할 경우 모니터링 장치로 전송하여 응급상황을 관리할 수 있다. 또한 제안된 시스템은 인간의 시각을 필요로 하는 철도 건널목이나, 교통량 통계조사, 공장 자동화 시스템 등 다양한 응용분야에 활용할 수 있는 최적의 선택이라 할 수 있다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 추계학술대회 논문집(제1권)
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• pp.509-514
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• 2006

본 연구는 준설선을 이용하여 가덕수도를 횡단하며 준설공사를 하는 동안의 선박들의 안전한 통항방안을 제시하는 것을 목적으로 한다. 부산${\sim}$거제간 연결도로 건설공사 중 가덕수도의 해저로 횡단하는 침매터널을 건설하기 위해서는 준설작업이 필요하다. 이에 따라 불가피하게 준설선이 가덕수도 항로를 횡단하며 준설을 해야 한다. 이는 상대적으로 가덕수도를 통항하는 선박들의 잠재적인 위험상황으로 충돌 등의 해난사고가 발생할 가능성이 있다. 따라서 이에 대한 선박의 안전통항방안을 모색하고 대책을 제시하였다.

• 한국자동차공학회논문집
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• 제13권4호
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• pp.58-65
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• 2005

A method measuring angular speed and estimating angular acceleration of an automotive wind shield wiper pivot with limited resources has been proposed. Limited resources refer to the fact that processes cannot be operated in real-time with a regular notebook running a Microsoft Windows. Also, they refer to the fact that data acquisition cards have only two general purpose counters as many generic cards do. An optical incremental encoder has been employed for measuring angular motion. To measure the angular speed of the pivot, periods for the encoder's output pulses have been measured as the speed is related to the reciprocal of the period. Since only information acquired from one counter channel is the magnitude of the angular speed, sign correction is necessary. Also the information for the exact time when a pivot passes left and right dead points is also missing and the situation is inherent to the hardware setup. To find out the zero-crossing time of the angular speed, a linear interpolation technique has been employed. Lastly, to overcome the imperfection of the mechanical encoders, the angular speed has been curve fitted to a spline. Angular acceleration can be obtained by a differentiation of the angular speed.

• 융합정보논문지
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• 제9권12호
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• pp.157-165
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• 2019

찰스 린드버그는 1927년 뉴욕에서 출발한 후 약 20시간 동안 대서양 횡단 비행 중 피로로 인해 잠든 동안 항공기가 통제되지 않는 상황을 경험하였다. NTSB(National Transportation Safety Board) 보고서에 따르면 매년 약 40건의 준사고가 피로와 관련되어 있는 것을 알 수 있다. 수면 손실은 알코올과 비슷한 효과를 유발할 수 있으며, NTSB에서 꾸준히 조사 중에 있는 부분이기도 하다. 피로는 특히 이륙 및 착륙 시 위협 및 오류 관리에 영향을 줄 수 있다. 본 연구에서는, NTSB가 일반적인 요인인 피로를 분석한 주요사고의 위협과 오류를 식별하고 피로의 심각성을 이해하고자 한다.

• 지식경영연구
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• 제20권2호
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• pp.105-135
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• 2019

This study investigates cognitive and emotional changes in individuals to clarify the principle between artistic stimulation and business innovation idea generation based on phenomenological research methodology. We conducted in-depth interviews with six participants who participated in the artistic creation program of business art, and derived meanings from their experience. As a result, we presented 4 essential categories, 8 main subjects, and 20 sub-subjects; 1) Optimizing rational and creative thinking, 2) Projecting oneself to the artist, finding balance, 3) Having room in mind to view the surroundings, finding insight into the world, 4) Eureka moment, crossing the boundary between business and art. We also found out participants of the program 1) Gradually expanded the criteria, 2) In chaotic directions, and 3) Leaded business creativity through from a non-form to reality throughout the project experience, The attempt to identify business phenomena by using phenomenological qualitative research methods had an academic significance regarding the unfamiliarity of the method in the business administration area. Moreover, this study broadened the possibility of promoting creativity by art in business areas. The study verified the categories and subjects of the business art, paving the way towards application in the real business situation.