• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 춘계학술대회
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• pp.551-555
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• 2009

본 연구에서는 태풍의 내습에 대비하여 부표에 계류하여 피항 중이던 해군함정의 계류체인이 절단된 원인을 분석하였다. 분석해 본 결과, 매우 흥미로운 사실을 확인 할 수 있었다. 즉, 실무부대에서는 계류체인이 절단된 원인을 선체가 받는 풍압력과 유압력 등이 계류체인의 절단강도를 초과하였기 때문인 것으로 알고 있었다. 그러나 본 연구결과에 의하면, 계류체인이 절단된 주요 원인은 선체와 계류체인의 접합 부위에서 발생하는 충격력 때문인 것으로 분석되었다. 또한, 본 연구에 의한 분석결과가 수리적 분석 측면에서 논리적이며, 절단 사고가 발생한 당시의 목격자들이 진술한 상황과도 일치한 점을 확인할 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.9-10
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• 2002

Human circulatory system between heart and tissue is not directly connected in normal condition but mandatory to go through the capillary system in order to fulfill its physiologic aim to deliver oxygen and nutrients, etc. to the tissue and retrieve used blood together with waste products from the tissue properly. When abnormal connection between arterial and venous system (AV fistula), these two circulatory systems respond differently to the hemodynamic impact of this abnormal connection between high pressure (artery) and low pressure (vein) system. Depending upon the location and/or degree (e.g. size and flow) of fistulous condition, each circulatory system exerts different compensatory hemodynamic response to this newly developed abnormal inter-relationship between two systems in order to minimize its hemodynamic impact to own system of different hemodynamic characteristics. Pump action of the heart can assist the failing arterial system directly to maintain arterial circulation against newly established low peripheral resistance by the AV fistula during the compensation period, while it affects venous system in negative way with increased venous loading. However, the negative impact of increased heart action to the venous system is partly compensated by the lymphatic system which is the third circulatory system to assist venous system independently with different hemodynamics. The lymphatic system with own unique Iymphodynamics based on peristaltic circulation from low resistance to high resistance condition, also increases its circulation to assist the compensation of overloaded venous system. Once these compensation mechanisms should fail to fight to newly established hemodynamic condition due to this abnormal AV connection, each system start to show different physiologic ${\underline{de}compensation}$ including heart and lymphatic system. The vicious cycle of decompensation between arterial and vein, two circulatory system affecting each other by mutually negative way steadily progresses to show series of hemodynamic change throughout entire circulation system altogether including heart. Clinical outcome of AV fistula from the compensated status to decompensated status is closely affected by various biological and mechanical factors to make the hemodynmic status more complicated. Proper understanding of these crucial biomechanical factors iii particular on hemodyanmic point of view is mandatory for the advanced assessment of biomechanical impact of AV fistula, since this new advanced concept of AY fistula based on blomechanical information will be able to improve clinical control of the complicated AV fistula, either congenital or acquired.

• 한국가스학회지
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• 제12권1호
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• pp.1-6
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• 2008

샤피충격시험은 동적하중 하에 있는 고분자 재료의 거동을 이해하는데 가장 널리 사용되고 있는 방법이다. 본 연구에서는 샤피충격시험장치에서 얻어지는 파단에너지를 사용하여 나일론 소재 샤피 시편의 노치각도에 따른 에너지 해방율을 구하는 방법을 제시하였다. 또한 샤피충격시험장치를 계장화하여 최대 하중과 파단 시까지 소요되는 에너지 등의 파손인자들을 산출하였다. 그리고 노치각도에 따른 동적파괴 인성치와 유한요소법을 사용하여 중앙집중 하중 하에서 사피 시편의 노치각도에 따른 응력분포를 산출하였다.

• 항공우주시스템공학회지
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• 제18권2호
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• pp.1-11
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• 2024

정보공유 기반의 네트워크 협업 유도탄에 대한 상대 충돌 각 유도기법을 불확실성과 외란이 존재하는 시스템에 적용했다. 협업 유도탄 시스템은 전이 축소 방향성 비순환 그래프로 표현되며, 그 구조에 따라 유도된 중앙집권형 및 분산형 유도기법을 소개했다. 또한, 소개된 유도기법을 유도탄의 통신 구조와 시스템 잡음 유무에 따라 비교하여 그 관계를 분석했다. 상대 충돌 각 제어 임무에서 분산형 정보공유 유도기법의 효과를 분석하기 위해 시스템 동역학에 잡음이 포함된 다수의 유도탄이 불확실성이 포함된 예상 요격 위치에 유도되는 상황을 가정하였다. 다양한 임무 환경에 대해 몬테카를로 시뮬레이션을 수행하였으며, 이를 통해 정보공유의 유무와 구조가 시스템에 미치는 영향을 분석했다.

• 한국지리정보학회지
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• 제9권4호
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• pp.34-44
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• 2006

환경모델링 기법은 비선형 오염유출현상을 구조화하여 배출특성 규명 및 정책대안의 영향예측 도구로서 활용도가 증가하고 있다. 반면 복잡한 입력 매개변수의 구성은 모형운영에 있어 비정량적 수치의 적용가능성을 내포하고 있다. 이러한 한계성을 극복하기 위해 최근 들어 GIS와 정보기술의 연계를 통한 자료관리 및 모형 매개변수 산출을 위한 연구들이 활발히 진행 중에 있다. 이에 본 연구의 목적은 NGIS사업을 통해 축척된 지형공간 자료와 GIS의 공간분석기능을 연계하여 유역 오염유출모형인 HSPF의 운영정보 생성을 지원하는 정보시스템을 개발하는데 있다. 주 연구내용은 시스템 분석 및 설계, 기초 데이터 수집과 DB 구축, 지형 매개변수 산정을 위한 GIS-HSPF의 통합 인터페이스 구축이다. 개발된 KBASIN-HSPF는 EPA에 의해 개발된 BASIN의 유역분할, 하천망생성, 지형특성계수 산정 기능과 함께 우리나라의 지형 오염원 기상정보의 저장구조를 고려한 데이터 모델링, Thiessen망에 준한 강우자료 보정 그리고 HSPF 모형운영정보 생성 및 전환기능을 포함하고 있다. KBASIN-HSPF는 기존의 오염유출모델링을 위해 자료준비부터 정보연계, 모형운영까지 분산된 환경에서 수행되었던 것을 통합환경하에서 진행함으로써 정보의 질적보장과 정보전환의 표준화방안을 제시하는 정보분석시스템이다.

• 산업경영시스템학회지
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• 제44권3호
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• pp.276-287
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• 2021

Project Management Information System (PMIS) is a special purpose information system that is created to provide useful information for project managers and participants to make effective and efficient decision making during projects. The use of PMIS is increasing in project based industries such as construction, defense, manufacturing, software development, telecommunication, etc. It is generally known that PMIS helps to improve the quality of decision making in project management, and consequently improves the project management performance. However, it is unclear what are the difference of PMIS impacts between industries, and still need to be studied further. The purpose of this study is to compare the impact of PMIS on project management performance between industries. We assume that the effects of PMIS will be different depending on the industry types. Five hypotheses are established and tested by using statistical methods. Data were collected by using a survey questionnaire from those people who had experience of using PMIS in various project related industries such as construction, defense, manufacturing, software development and telecommunication. The survey questionnaire consists of 5 point scale items and were distributed through e-mails and google drive network. A total of 181 responses were collected, and 137 were used for analysis after excluding those responses with missing items. Statistical techniques such as factor analysis and multiple regression are used to analyze the data. Summarizing the results, it is found that the impacts of PMIS quality on the PM performance are different depending on the industry types where PMIS is used. System quality seems to be more important for improving the PM performance in construction industry while information quality seems more important for manufacturing industry. As for the ICT and R&D industries, PMIS seems to have relatively lesser impact compared to construction and manufacturing industries.

• 한국컴퓨터정보학회논문지
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• 제22권10호
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• pp.167-177
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• 2017

In this paper, we propose the role of job crafting in the relationship between leadership and organizational effectiveness in voluntarily carrying out each member's assigned tasks. This study surveyed the manufacturing, construction, service industries in Seoul and Gyeonggi province, identified the type of leadership they recognized, and empirically analyzed the organizational effectiveness of leadership. The purpose of this paper is to grasp the types of leadership acknowledged by the industry of manufacturing, construction, and service, and also to empirically analyze the organizational effectiveness of the leadership. The study measures the organizational effectiveness in terms of the job satisfaction, organizational commitment, and organizational citizenship behavior while classifying the leadership into coaching leadership, transformational leadership, and sensible leadership. In addition, the strictness of the analysis is imposed by estimating the simple least square model and ranking probit model. The results of the least square model is summarized as the following. Regardless of the different defining terms of organizational effectiveness, transformational leadership was shown to have the greatest organizational effectiveness. Sensible leadership positively effected job satisfaction whereas coaching leadership positively effected job satisfaction and organizational effectiveness. Compared to transformational leadership and coaching leadership, the impact of the sensible leadership was very much limited. The result of the ranking probit model is summarized as the following. First, sensible leadership had a positive impact on the member's job satisfaction and organizational commitment. Second, regarding the organizational citizenship behavior, coaching leadership showed greater impact than transformational leadership. This results contradicts the results from the simple least square model. If similar studies were to be conducted in the future, two models and the results must be compared. Third, as the leadership score increases by 1 point, there is greater possibility of having more than 4 points for all job satisfaction, organizational commitment, organizational citizenship behavior. Lastly, the analysis proves that job crafting has the mediation effect between the leadership and organizational effectiveness.

• 한국정보통신학회논문지
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• 제7권1호
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• pp.129-135
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• 2003

광섬유 센서의 주된 이점으로는 기계적 구동부가 없으므로 고신뢰성, 긴수명, 무전기적 간섭, 고응답속도, 저가이다. 본 연구에서는 공장설비 및 자동문 등과 같은 곳에서 많이 사용되어지는 자동장치의 오작동으로 인한 사고를 미연에 감지하여 인명피해를 줄이기 위하여 광섬유를 이용한 충격 및 압력센서를 제안 및 개발하였다. 센서의 원리로는 충격에 의해 다중모드 광섬유에서 발생하는 스펙클 패턴의 변화를 포토다이오드로 검출하는 방식이다. 광섬유에 충격의 세기를 변화하여 여러 차례 측정한 결과 충격의 세기의 변화에 따른 반응정도는 선형적으로 변하지는 않았으나 주어진 충격에 대해 민감하게 반응하는 것을 실험을 통하여 확인하였으며 광섬유의 피복 두께의 변화나 신호처리부에서의 증폭도를 조절함으로써 충격에 대한 반응감도를 조절할 수 있었다. 광섬유를 이용한 충격 및 압력센서의 장점으로는 점대점 방식이 아닌 라인 방식으로 설치하거나 측정함으로써 광섬유 전체가 센서역할을 하기 때문에 설치가 용이하고 감지범위가 넓어 센서로서의 우수한 특성을 가지므로 다양한 자동시스템 분야나 충격 및 압력센서로 활용될 수 있을 것이다.

• 한국물환경학회지
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• 제34권4호
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• pp.382-390
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• 2018

In this study, the LIDMOD3 was developed to design and evaluate low impact development (LIDMOD). In the same fashion, the LIDMOD3 employs a curve number (NRCS-CN) method to estimate the surface runoff, infiltration and event mean concentration as applicable to pollutant loads which are based on a daily time step. In these terms, the LIDMOD3 can consider a hydrologic soil group for each land use type LID-BMP, and the applied removal efficiency of the surface runoff and pollutant loads by virtue of the stored capacity, which was calculated by analyzing the recorded water balance. As a result of Model development, the LIDMOD3 is based on an Excel spread sheet and consists of 8 sheets of information data, including: General information, Annual precipitation, Land use, Drainage area, LID-BMPs, Cals-cap, Parameters, and the Results. In addition, the LIDMOD3 can estimate the annual hydrology and annual pollutant loads including surface runoff and infiltration, the LID efficiency of the estimated surface runoff for a design rainfall event, and an analysis of the peak flow and time to peak using a unit hydrolograph for pre-development, post-development without LID, and as calculated with LID. As a result of the model application as applied to an apartment, the LIDMOD3 can estimate LID-BMPs considering a well spatical distributed hydroloic soil group as realized on land use and with the LID-BMPs. Essentially, the LIDMOD3 is a screen level and simple model which is easy to use because it is an Excel based model, as are most parameters in the database. This system can be expected to be widely used at the LID site to collect data within various programmable model parameters for the processing of a detail LID model simulation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권11호
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• pp.2992-3007
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• 2012

Recently there has been an increasing interest in exploring the radio irregularity research problem in Wireless Sensor Networks (WSNs). Measurements on real test-beds provide insights and fundamental information for a radio irregularity model. In our previous work "LMAT", we solved the path planning problem of the mobile anchor node without taking into account the radio irregularity model. This paper further studies how the localization performance is affected by radio irregularity. There is high probability that unknown nodes cannot receive sufficient location messages under the radio irregularity model. Therefore, we dynamically adjust the anchor node's radio range to guarantee that all the unknown nodes can receive sufficient localization information. In order to improve localization accuracy, we propose a new 2-hop localization scheme. Furthermore, we point out the relationship between degree of irregularity (DOI) and communication distance, and the impact of radio irregularity on message receiving probability. Finally, simulations show that, compared with 1-hop localization scheme, the 2-hop localization scheme with the radio irregularity model reduces the average localization error by about 20.51%.