• 한국항공우주학회지
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• 제48권12호
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• pp.987-995
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• 2020

고성능 탑재체들과 자세제어 센서들 간의 정밀정렬은 인공위성의 정확한 자세지향 및 높은 지향 안정성을 위해 필수적이다. 위성 개발사들은 조립 및 시험기간 동안 위성 정렬을 위해 데오드라이트 측정 시스템을 주로 사용한다. 데오드라이트 측정 시 시선 방향 오차, 수평축의 오차, 수직방향 인덱스 오차 그리고 수직축 오차로 인해 측정오차가 발생할 수 있다. 이러한 오차들 뿐 아니라 다수의 데오드라이트를 사용한 측정 시 발생할 수 있는 오차들을 정렬큐브 측정실험을 통해 분석하였다. 정렬큐브 측정실험을 기반으로 정렬측정 정확도를 향상시킬 수 있는 방법이 제안되었고, 측정 결과 위성의 설계 요구조건도 만족시킬 수 있었다.

• 한국압력기기공학회 논문집
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• 제17권2호
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• pp.109-118
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• 2021

In the periodic surveillance material test for the spacer component of fuel channel assembly in CANDU, a microstructural characterization analysis is required in addition to the mechanical property evaluation test. In this study, detailed microstructure analysis and simple mechanical property evaluation of archive spacer parts were conducted to indirectly support the surveillance test and assist in the study of spacer material degradation. We investigated the microstructural characteristics of the spacer garter spring coil through comparative analysis with the plate material. The main microstructure characteristics of the garter spring coil X-750 are represented by the fine grain size distribution, the ordering phase distribution developed inside the matrix, the high dislocation density inside the grains, and the arrangement of coarse carbides. In addition, the yield strength of the garter spring coil X-750 was indirectly evaluated to be approximately 1 GPa. We also established an analytical method to elucidate the microstructural evolution of the radioactive spacer garter spring coil X-750 based on Canadian research experiences. Finally, we confirmed the measurement technique for helium bubble formation through TEM examination on the helium implanted X-750 material.

• 한국문헌정보학회지
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• 제52권1호
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• pp.313-340
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• 2018

본 연구는 우리나라 공공기관 고객만족 조사에 보편적으로 활용되고 있는 "공공기관 고객만족지수(Public-service Customer Satisfaction Index, PCSI)모형"을 도서관에 적용하여 측정함으로써 고객만족 결과를 조직의 성과평가에 활용할 수 있는 기반을 마련하고자 하였다. 이를 위해 국회도서관을 대상으로 하여 PCSI 기반의 고객만족도 조사 모형을 설계하고 국회도서관 이용자 341명으로부터 수집한 설문조사를 통해 모형을 검증하였다. 분석 결과, 국회도서관이 이용자에게 제공하는 각종 서비스의 품질은 고객만족의 원인이 되고, 고객만족은 또 조직성과에 직접적으로 영향을 미치고 있으며 서비스의 환경품질과 사회품질요인이 고객만족도에 긍정적인 영향을 주는 것으로 파악되었다. 또한 선행요인모형, 만족모형, 성과모형 모든 영역에서 외부이용자가 내부이용자에 비해 높은 점수를 보였고 PCSI의 고객만족모형을 통해 산출된 고객만족 점수는 80.4로 나타났다. 본 연구는 고객만족을 통해 조직의 성과를 측정하는 이론적 체계를 확보하는 동시에, 이용자 관점에서 성과목표 달성 정도를 측정하는 성과관리 도구로 활용할 수 있다.

• International Journal of Aeronautical and Space Sciences
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• 제13권1호
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• pp.117-125
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• 2012

This paper presented the design of SRPS, ground function test, and the deployment test on a high speed taxi of KC-100 airplane. KAI has developed a spin recovery system in collaboration with Airborne Systems for KC-100 general aviation airplane. Spin mode analysis, rotary balance and forced oscillation tests were performed to obtain the rotational, dynamic derivatives in the preliminary design phase. Prior to the detailed design process of SRPS, approximations for initial estimation of design parameters- fineness ratio, parachute porosity, parachute canopy filling time, and deployment method- were considered. They were done based on the analytical disciplines such as aerodynamics, structures, and stability & control. SRPS consists of parachute, tractor rocket assembly for deployment, attach release mechanism (ARM) and cockpit control system. Before the installation of SRPS in KC-100 airplane, all the control functions of this system were demonstrated by using SBTB(System Breakout Test Box) in the laboratory. SBTB was used to confirm if it can detect faults, and simulate the firing of pyrotechnic devices that control the deployment and jettison of SRPS. Once confirmed normal operation of SRPS, deployment and jettison of parachute on the high speed taxiing were performed.

• 한국산업보건학회지
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• 제11권1호
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• pp.56-69
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• 2001

Objectives : This study was designed to develop and standardize a checklist for ergonomic risk factors, and to provide ergonomic guidelines for managing cumulative trauma disorders (CTDs) in automobile assembly lines. Methods : The Checklist for Ergonomic Risk Factors (CERF-1) was developed based on the results of previous studies, and then modified after performing pilot study. Information on the symptoms possibly related with CTDs was obtained using a self-reported Questionnaire from 465 automobile assembly workers. Their job conditions were examined to assess risk factors through both direct observation and video analysis. Results : Rate of detecting risky job through CERF-1 was 85.6%, and was similar to that (88.8%) by Occupational Safety and Health Adminstration(OSHA) checklist but higher than that (63.7%) by American National Standards Institute(ANSI) Z-365. Relationship of the exposure scores derived from CERF-1 with levels of symptom was greater (r=0.49) than OSHA (r=0.28) and ANSI Z-365 (r=0.22). Considering the relationship, jobs scoring higher than 16 could be classified as the Risk Job. and lower than 16 as the Low Risk Job. Sensitivity and specificity of the Risk Job were 92.5 % and 31.5 %, respectively. Odds ratio (OR) after age adjustment was 5.69 (95 % confidence interval 3.15-10.29) for the Risk Job, and these ORs were significantly different from those of the Low Risk Job. The exposure scores were Quite valid, in that the scores at the main survey were significantly correlated with those at the follow-up survey, as suggested by test-retest(r=0.88) and inter-rater reliability(r=0.80). Conclusions : The CERF-1, developed in this study, will be an efficient tool for evaluation of risk jobs for CTDs in automobile assembly lines, and can be used easily by health care providers.

• Asian review of World Histories
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• 제4권1호
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• pp.83-123
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• 2016

We describe a vision of historical analysis at the world scale, through the digital assembly of historical sources into a cloud-based database, where machine-learning techniques can be used to summarize the database into a time-integrated actor-to-actor complex network. Using this time-integrated network as a template, we then apply the method of automatic narratives to discover key actors ('who'), key events ('what'), key periods ('when'), key locations ('where'), key motives ('why'), and key actions ('how') that can be presented as hypotheses to world historians. We show two test cases on how this method works. To accelerate the pace of knowledge discovery and verification, we describe how historians would interact with these automatic narratives through an online, map-based knowledge aggregator that learns how scholars filter information, and eventually takes over this function to free historians from the more important tasks of verification, and stitching together coherent storylines. Ultimately, multiple coherent storylines that are not necessary compatible with each other can be discovered through human-computer interactions by the map-based knowledge aggregator.

• 한국산업융합학회 논문집
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• 제17권2호
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• pp.54-60
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• 2014

The equipment of SCARA robot in processing and assembly lines has rapidly increased. In order to achieve high productivity and flexibility, it becomes very important to develop the visual feedback control system with Off-Line Programming System(OLPS). We can save much efforts and time in adjusting robots to newly defined workcells by using OLPS. A proposed visual calibration scheme is based on position-based visual feedback. The calibration program firstly generates predicted images of objects in an assumed end-effector position. The process to generate predicted images consists of projection to screen-coordinates, visible range test, and construction of simple silhouette figures. Then, camera images acquired are compared with predicted ones for updating position and orientation data. Computation of error is very simple because the scheme is based on perspective projection, which can be also expanded to experimental results. Computation time can be extremely reduced because the proposed method does not requirethe precise calculation of tree-dimensional object data and image Jacobian.

• 한국정보과학회논문지:소프트웨어및응용
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• 제32권8호
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• pp.704-716
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• 2005

미리 만들어진 컴포넌트를 조립하여 새로운 소프트웨어를 개발하는 방법은 개발비용과 기간을 획기적으로 줄일 수 있다는 장점으로 전통적인 방법의 대안이 되고 있다. 하지만 컴포넌트를 통합 조립하면서 신뢰도를 확인하고 새 환경에 맞는지 테스트하는 과정이 복잡하고 비용이 많이 소요된다면 효과적인 방법이 될 수 없다. 대규모 시스템에 효율적으로 사용, 조림될 컴포넌트들은 원시코드 형태로 배포되지 않아서 새 환경에 적합한지 시험하고 관찰하는 철저한 테스트가 어렵다. 이러한 문제점을 해결하기 위하여 컴포넌트가 재사용되었을 때 쉽게 검증되도록 미리 테스트 모듈을 내장한 Built-In 테스트 방법이 있지만 컴포넌트의 기능이 다양하고 복잡하게 되면 컴포넌트에 포함된 테스트 모듈의 규모가 커지고 다양하고 융통성 있는 테스트가 어려워진다. 이 논문에서는 컴포넌트의 Built-In 테스트 기능을 대체할만한 컴포넌트 테스트를 위한 래퍼(wrapper)를 제안하고 이를 설계, 구현하여 실용성을 보였다. 래퍼를 자동 생성하여 테스트하면 컴포넌트의 테스트 준비 과정에 드는 노력이 줄어들고 테스트를 다양한 측면에서 테스트해 볼 수 있다.

• 대한안전경영과학회지
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• 제10권2호
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• pp.1-13
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• 2008

This Study is to analyze the characteristics of arson fire under fire dynamics to protect people and property from arson fire which has been radically increased with the development of the Korean economy. Assembly and merchandise purposes such as theater, retail, and exhibition has been performed as the arson fire study. The experiment for this study is based on the analysis of the characteristic for its own combustion process and smoke spread when arson fire occurs. This study presents the analysis through comparing the condition of setting fire using liquid fuel such as thinner on purpose to the condition of setting fire naturally depending on each occupancy.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1617-1620
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• 1997

This paper describes the camera caliberation based-neural network with a camera modeling that accounts for major sources of camera distortion, namely, radial, decentering, and thin prism distortion. Radial distoriton causes an inward or outward displacement of a given image point from its ideal location. Actual optical systems are subject to various degrees of decentering, that is the optical centers of lens elements are not strictly collinear. Thin prism distortion arises from imperfection in lens design and manufacturing as well as camera assembly. It is our purpose to develop the vision system for the pattern recognition and the automatic test of parts and to apply the line of manufacturing. The performance of proposed camera aclibration is illustrated by simulation and experiment.