• Journal of KIISE:Software and Applications
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• v.37 no.7
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• pp.584-589
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• 2010

The dynamic time warping algorithm generally used in time series pattern recognition spends most of the time in generating the correlation table, and it establishes the global path constraint to reduce the corresponding time complexity. However, the constraint restrains just in terms of the time axis, not considering the contents of input patterns. In this paper, we therefore propose an efficient branch and bound dynamic time warping algorithm which sets the global constraints by adaptively reflecting the patterns. The experimental results show that the proposed method outperforms conventional methods in terms of the speed and accuracy.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.2
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• pp.115-121
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• 2002

This report summarized the static test of the rudder system for the KTX-1 basic trainer. The test loads are applied up to the limit and ultimate loads in a stepping sequence. Test loads and test results matt the strength and stiffness requirements of the rudder control system.. Using #004 full scale structure test airframe.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.5
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• pp.783-791
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• 2006

In e-Trade, Real-Time System(RTS) plays a very important role. Each task is set with limited time, and appointed regulations must be followed because it can be greatly damaged if it cannot be executed in limited time. In e-Trade, the scheduling possibility techniques generally use periodical tasks; however, it is necessary to study more stable prediction scheduling possibility algorithm by using other task timing conditions and non-periodical task scheduling tasks. This study proposed an algorithm to increase the prediction possibility using individual task utilization rate, and presented scheduling possibility conditions using existing whole task utilization rate and the proposed algorithm.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.182-185
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• 2011

본 논문에서는 국내 고속철도 차량 즉, 경부고속철도를 운행하는 KTX, KTX산천 그리고 현재 개발중인 HEMU400x을 대상으로 운행속도 및 운행패턴에 따른 열차 소비전력을 분석하였다. 이를 위해, 선로조건을 고려한 차량의 운전속도 조건과 운행시간,소비전력 등을 예측하기 위한 TPS(Train Performance Simulation)프로그램을 이용하였다. 열차운행 시뮬레이션을 수행하기 위해선 차량, 선로, 속도의 기본 데이터를 필요로 한다. 차량에 대한 데이터는 차량의 최고속도, 제동성능, 견인력 등의 기본 성능과 열차편성에 따른 중량, 길이, 동력차량형식, 열차주행저항등에 대한 제원을 요한다. 선로데이터는 운행시간 예측을 대상으로 하는 선로에 대한 거리별 구배 및 선형, 정거장 위치 및 정차시간에 대한 데이터이다. 속도조건은 구배 및 곡선에 대한 선로제한속도로, 선로데이터와 연계하여 각 선로위치별 차량의 제한속도로 이용된다. 본 논문에서는 경부고속철도 구간에서 운행하는 고속차량 3가지를 대상으로 증속에 따른 전력소모량을 비교하였다.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.35-42
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• 2005

Few studies have been carried out to find out the interaction of design speeds, operating speeds, and posted speeds though they have a complementary relationships. As an attempt to find the relationships, this study measured the speeds of the free flowing vehicles at four lane rural highways. In comparison of 95th percentile speeds and inferred design speeds determined from the road design manual with the geometric features of each sites, operating speeds were constantly higher than the inferred design speeds at the sites where the inferred design speed is under 110km/h. and the reverse situation was observed at the sites where the inferred design speed is over 130km/h. In the comparison of operating speeds and posted speeds. the range of the 85th percentile speeds at the sites where posted speeds is 80km/h was distributed from 95km/h to 110km/h. and the range was distributed from the 105km/h to the 120km/h at the sites where posted speeds is 90km/h. Multiple regression analysis was used to develop prediction equations for mean. 85th. and 95th percentile speeds at approach and curve midpoint locations. At the midpoint, only posted speeds influenced the mean, 85th. At the approach locations, the mean, 85th, 95th percentile speeds were influenced by posted speeds and length of the approach tangent.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10b
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• pp.223-225
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• 1998

실시간 감시(monitor) 및 제어(control) 시스템의 데이터베이스는 계속적으로 감지기(sensors)에 의해 갱신된다. 연속적인 데이터의 변화에 의한 제약조건(constraints) 위반은 시스템에 심각한 문제를 발생시킨다. 이러한 시스템의 감시 및 제어를 능동적(active)으로 제공하기 위한 기능의 보편적인 형태로 능동규칙(Active rules)을 사용한다. 능동규칙은 정의된 사건(event)이 발생하면, 데이터베이스 상태의 변화에 대한 조건(condition)에 의해 행동(action)을 수행한다. 무결성(integrity) 제약조건을 능동규칙으로 선언함으로써 데이터베이스의 상태를 감시 및 제어하는 것이다. 일반적으로 사용되어온 능동규칙은 제한적인 시간상 무결성 제약조건 검사를 허용하고 있으며, 최근 능동규칙을 사용하여 시간상 연속적인 데이터베이스의 변화에 대한 제약조건 및 트리거(trigger)를 제공하기 위한 연구의 필요성이 대두되고 있다. 이 논문은 사건 빈도와 연합된 시간상에 연속적인 데이터베이스 상태 변화의 확장된 시간조건 상술을 지원하는 시간능동 규칙을 제안한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.37-37
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• 1998

중형항공기용 터보펜 엔진의 성능모사와 LQR 제어기 설계에 대한 연구를 수행하였다. 동적 성능모사를 설계점으로 선정한 지상최대이륙조건과 탈설계점으로 선정한 최대상승조건과 순항조건에 대하여 Step 증가, Ramp 증가, Ramp 감소, Step증가 후 Ramp 감소의 4가지 연료공급에 조건에 대하여 수행되었다. 성능모사 결과 모든 비행조건에서 연료를 Step 증가시킬 경우 고압터보빈의 입구온도가 제한온도인 3105$^{\circ}$R을 초과함을 확인하였고, 최대 상승조건에서 연료를 Step 증가시킬 경우가 4.5초 이내에 Ramp 증가시킬 경우 고압압축기에 서지가 발생함을 확인하였다. 따라서 고압터어빈의 오버슈트와 고압압축기의 서지를 동시에 제어할 수 있는 다변수 제어기의 설계가 필요함을 확인하였다.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.204-210
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• 2017

In this study, we analyzed the descriptions of the electron movement model and the oxidation number change model presented in the 2009 revised curriculum and textbooks. We also investigated chemistry education major teachers' conceptions of limitations of each model. The electron movement model and oxidation number change model were presented in the curriculum and the textbooks. However, hybrid model was also presented which fail to grasp the limitation of each model. The hybrid model explains redox reactions of covalent bond compounds by electron movement model or even if it explains redox reactions by oxidation number change model, this explanations have the problem of confusing the virtual electron movement with the actual electron movement. A questionnaire and interviews were conducted to investigate chemistry education major teachers' perceptions of redox reactions. As results, many teachers did not recognize the limitations of each model and had difficulties to distinguish redox reactions from acid-base reactions because of the hybrid model.

• Journal of the HCI Society of Korea
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• v.12 no.3
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• pp.13-23
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• 2017

In this paper, we propose a new in-hand 3D modeling system that improves user convenience. Since traditional modeling systems are inconvenient to use, an in-hand modeling system has been studied, where an object is handled by hand. However, there is also a problem that it requires additional equipment or specific constraints to remove hands for good modeling. In this paper, we propose a contact state change detection algorithm for automatic hand removal and improved ICP algorithm that enables outlier handling and additionally uses color for accurate registration. The proposed algorithm enables accurate modeling without additional equipment or any constraints. Through experiments using real data, we show that it is possible to accomplish accurate modeling under the general conditions without any constraint by using the proposed system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.9
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• pp.1010-1019
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• 2016

The K-user multiple-input single-output broadcast channel is considered under per-antenna power constraints, i. e., each transmit antenna must satisfy its own power constraints. A low complexity zeroforcing(ZF) precoder is proposed when the number of transmit antennas M is greater than K. The proposed precoder design significantly reduces computational complexity for the precoder construction while attaining the sum spectral efficiency close to that achievable by the optimal ZF precoder.