• 한국강구조학회 논문집
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• 제13권5호
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• pp.525-533
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• 2001

교량의 내풍 안전성을 평가하기 위해서는 플러터 계수(Flutter Derivatives)의 안정적 추정이 필요하다. 본 논문에서는 풍동실험에서 얻어지는 시간영역에서의 데이터중 변위 시계열데이터를 이용해서 플러터 계수를 구하는 동특성 계수 측정기법 2가지를 검토하였다. 검토된 MITD(Modified Ibrahim Time Domain) 방법과 AKF(Adaptive Kalman Filtering) 방법은 2차원단면모형 실험으로부터 동시에 8개의 플러터 계수를 산출할 수 있는 유용한 방법이다. 제안된 방법의 실제상황에서의 적용성을 검토하기 위해서 Bandlimited Gausian white noise을 가상의 데이터에 첨가하여 수학적 시뮬레이션으로 잡음에 대한 안정성을 검증해 보았다. 그 결과 교량의 플러터 해석에서는 본 연구에서 검증된 MITD 방법을 통한 플러터 계수의 산출이 추전된다.

• Smart Structures and Systems
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• 제14권1호
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• pp.55-70
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• 2014

The paper presents a multi-objective optimization strategy for a multi-type sensor placement for Structural Health Monitoring (SHM) of long span bridges. The problem is formulated for simultaneous placement of strain sensors and accelerometers (heterogeneous network) based on application demands for SHM system. Modal Identification (MI) and Accurate Mode Shape Expansion (AMSE) were chosen as the application demands for SHM. The optimization problem is solved through the use of integer Genetic Algorithm (GA) to maximize a common metric to ensure adequate MI and AMSE. The performance of the joint optimization problem solved by GA is compared with other established methods for homogenous sensor placement. The results indicate that the use of a multi-type sensor system can improve the quality of SHM. It has also been demonstrated that use of GA improves the overall quality of the sensor placement compared to other methods for optimization of sensor placement.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제11권1호
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• pp.1-14
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• 2005

컨포넌트 개발 프로세스에서 재사용 가능한 독립적인 컴포넌트의 식별은 가장 중요한 작업이면서 어려운 작업이다. 따라서 현존하는 컴포넌트 개발 방법론들에서는 컴포넌트 식별을 위해서 체계적이고 명확한 기준이 제시되지 않아 대다수 개발자의 직관과 경험에 의존하고 있다. 그 결과 평이한 개발자에 의해서 소프트웨어의 재사용 단위인 컴포넌트를 식별하기가 쉽지 않다. 따라서 본 논문에서는 컴포넌트를 용이하게 식별할 수 있도록 유스케이스 다이어그램, 클래스 다이어그램 그리고 시퀀스 다이어그램 등 도메인 모델을 기반으로 컨포넌트를 식별하는 기준과 방법을 제시한다. 본 논문에서는 2단계 즉, 시스템 컨포넌트 식별과 비즈니스 컴포넌트 식별을 통하여 컴포넌트론 식별하는 방법을 제시한다. 특히, 제안된 기법에서는 컴포넌트 식별에 있어서 구조적 특성뿐만 아니라 메소드 호출 유형과 방향에 따른 의존성 특성을 함께 괴려하고 있다 이러한 제안된 기법의 실용성을 검증하기 위해 사례 연구와 기존 식별 방법과의 비교 분석 및 평가를 제시한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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• pp.133-136
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• 1999

Many researches on the identification of a system have been carried out using a least square method, an adaptive filter, and so on. However, it is difficult to apply these methods in a nonlinear system. In the case of a nonlinear system, it is known that the signal compression method is able to estimate uncertain parameters of linear element in a nonlinear system because it is able to separate linear element and nonlinear element in a nonlinear system. However, the signal compression method cannot be applied to a motion simulator because actuators of the simulator is single-rod cylinders which includes expansion and compression dynamic properties. Therefore, this paper proposes a modified signal compression method which is able to estimate uncertain parameters of the motion simulator dynamics. The dynamic properties of this system are identified by separating expansion and compression properties when applying the signal compression method. And then, the identified parameters are applied to design a sliding mode controller for the simulator. The performance of the designed sliding mode controller is evaluated experimentally.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.173-176
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• 2008

우리나라는의 선박자동식별시스템은 국제협약에 의거 강제시행됨에 따라, 정부에서는 2002년부터 정부예산을 투입하여 현재까지 육상기지국 33개소, 운영시스템 11기 및 전국통합망 구축사업을 추진하여 왔으며, 다양한 해상안전분야에서 활용되고 있다. 그러나 현재의 해상교통량 조사 및 분석방법에 있어서는 대부분이 레이더 기반의 VTS관제센터에서 수집된 정보를 조사함으로써 항만위주의 해역에 대한 교통량 분석이 이뤄지고 있는 실정이다. 따라서 이 논문에서는 AIS 전국망 데이터를 조사 분석하여 우리나라 전해상의 AIS 통신 음영지역 및 커버리지에 대한 분석 및 공해상에서 선박의 이동경로 분석 및 교통량을 분석함으로써 효율적인 연안관제 및 해싱관제 업무에 활용할 수 있도록 AIS기반의 해상교통량 조사 분석 시스템을 개발하고 그 내용을 소개하였다.

• 대한한의정보학회지
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• 제21권2호
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• pp.11-23
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• 2015

Objectives : Through a comparative study between Sasang constitutional medicine and Syndrome identification and treatment medicine about the theory of diagnosis, the theory of herbal medicine, the theory of prescription, the theory of acupuncture and constitutional medicine to put forward a complementary perfect solution which has good clinical utility. Methods : We compared and sorted out the textbook of Korean Sasang constitutional medicine which named Sasang medicine, and also the textbook of Chinese TCM which was including Basic theory of TCM, Diagnostics of TCM, Science of Chinese materia medica, Pharmacology of traditional Chinese medical formulae, Science of acupuncture and moxibustion, Constitution of TCM, and also related papers. Results : (1) Through a comparative study between Sasang constitutional medicine and Syndrome identification and treatment medicine about diagnosis, herbal medicine, prescription and acupuncture, Sasang constitutional medicine is a medical system which gives priority to balance of organs, when Syndrome identification and treatment medicine is a medical system that gives priority to improve symptom. (2) The prescriptions of Sasang constitutional medicine are used for the treatment of basic pathogenesis in the chronic stage of the disease, which can recover vital qi, when Syndrome identification and treatment medicine are used for the treatment of stage pathogenesis in the acute stage of the disease, which can get rid of pathogenic factors. (3) There are two kind of complementary perfect solution between Sasang constitutional medicine and Syndrome identification and treatment medicine. One perfect complementary medicine is that Sasang constitutional medicine plays a major role when Syndrome identification and treatment medicine plays a supporting role. The other one is that Syndrome identification and treatment medicine plays a major role when Sasang constitutional medicine plays a supporting role. It determined by the usual symptoms and the symptoms now, vital qi and pathogenic factors, symptom and the root cause, acute stage and chronic stage, and the state of pathogenesis. Conclusion : A new perfect complementary medicine can be created which is based on the setting that Sasang constitutional medicine primarily treat the usual symptoms, vital qi, the root cause, chronic stage and basic pathogenesis when Syndrome identification and treatment medicine primarily treat the symptoms now, pathogenic factors, symptom, acute stage and stage pathogenesis.

• 한국구조물진단유지관리공학회 논문집
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• 제8권2호
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• pp.137-145
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• 2004

본 연구에서는 구조성질들이 제대로 평가되지 않은 구조물의 부분구조 모델을 설정하는 방법을 제시한다. 본 연구에서는 부분구조 모델을 정의하기 위해 구조물의 대상 부분구조에서 계측한 구조거동치를 필요로 하며, 부분구조 모델은 부분구조 자체의 강성도변수와 경계스프링 계수를 추정하여 설정한다. 정적 및 주파수영역 SI(system identification) 기법들이 부분구조의 제한된 위치에서 측정된 거동치를 사용하여 적용되었다. 정적거동과 동적거동 계측 각각에 대한 시뮬레이션 연구가 수행되었으며, 연구결과 및 문제점들이 검토되었다. 시뮬레이션 연구에서 검증된 절차에 따라 이동트럭과 시공발파에 의한 동적거동 계측치를 사용하여 실제의 다경간 플레이트 거더 게르버교의 부분구조 모델 설정을 수행하였다.

• Smart Structures and Systems
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• 제15권2호
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• pp.425-445
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• 2015

Parametric identification of structures is one of the important aspects of structural health monitoring. Most of the techniques available in the literature have been proved to be effective for structures with small degree of freedoms. However, the problem becomes challenging when the structure system is large, such as bridge structures. Therefore, it is highly desirable to develop parametric identification methods that are applicable to complex structures. In this paper, the LSE based techniques will be combined with the substructure approach for identifying the parameters of a cable-stayed bridge with large degree of freedoms. Numerical analysis has been carried out for substructures extracted from the 2-dimentional (2D) finite element model of a cable-stayed bridge. Only vertical white noise excitations are applied to the structure, and two different cases are considered where the structural damping is not included or included. Simulation results demonstrate that the proposed approach is capable of identifying the structural parameters with high accuracy without measurement noises.

• ETRI Journal
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• 제30권5호
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• pp.653-662
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• 2008

Arbitration of tag collision is a significant issue for fast tag identification in RFID systems. A good tag anti-collision algorithm can reduce collisions and increase the efficiency of tag identification. EPCglobal Generation-2 (Gen2) for passive RFID systems uses probabilistic slotted ALOHA with a Q algorithm, which is a kind of dynamic framed slotted ALOHA (DFSA), as the tag anti-collision algorithm. In this paper, we analyze the performance of the Q algorithm used in Gen2, and analyze the methods for estimating the number of slots and tags for DFSA. To increase the efficiency of tag identification, we propose new tag anti-collision algorithms, namely, Chebyshev's inequality, fixed adjustable framed Q, adaptive adjustable framed Q, and hybrid Q. The simulation results show that all the proposed algorithms outperform the conventional Q algorithm used in Gen2. Of all the proposed algorithms, AAFQ provides the best performance in terms of identification time and collision ratio and maximizes throughput and system efficiency. However, there is a tradeoff of complexity and performance between the CHI and AAFQ algorithms.

• 대한한의진단학회지
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• 제14권1호
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• pp.70-78
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• 2010

Objectives : To qualify or enhance the diagnostic ability of students in Oriental Medicine, so called standardized patients are ideal modality, but because it's a man-based method, more convenient tools are required. Computer-based diagnostic ability test program gives effective way for the very purpose. So we made a pilot software evaluating Pattern Identification ability in Oriental Medicine. Methods and Materials : The pilot software was coded with Microsoft's EXCEL VBA. 87 names of Zheng (Symptom Pattern) and 674 names of symptom (including some signs) are adopted from the former standardization works conducted by Korean Institute of Oriental Medicine (KIOM) in 1996. Results : Compared with some manned modalities to test Pattern Identification ability, the test by this software shows superiority in convenience and objectivity. Conclusion : This software is world's first program to perform computer-based evaluation of Pattern Identification in Oriental Medicine, and it gives effective way to complement both written test and manned clinical performance test (CPX).