• 드라이브 ㆍ 컨트롤
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• 제14권3호
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• pp.50-57
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• 2017

Recently, methods of verification for electro-hydraulic servo controllers are various and the required number of testing controllers is continuously increasing in some specific systems. In this study, a PCB-based electronic simulator of hydraulic actuators is designed and developed to simplify test set-up for controllers and to facilitate alteration for characteristics of the simulator. Several features to reduce required time and manpower for verifying controllers are described. Especially, the simulator is considerably efficient to examine some controllers for different hydraulic actuators in a test. Response characteristics of the simulator are compared with those of real actuators to demonstrate validity of this method. Results reveal utilizing the designed simulator for inspecting controllers is equally effective as using hydraulic actuators.

• 소성∙가공
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• 제4권1호
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• pp.9-16
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• 1995

Model material technique, which requires only the small space of experimental set-up and low cost for experiment, is used to estimate the deformed profile and the forging load in rotary forging. The materials and working conditions are determined to satisfy the similitude conditions between the model test and the prototype test. The model material of the so-called plasticine and the mild steel are chosen as specimens, and they represent almost the same value of strain gardening exponent in the stress-strain relationship. Lubricant in the model test is also carefully selected so that it gives the same frictional conditions at the tool-specimen interface. Experiments for two kinds of specimens are carried out in each testing equipment at room temperatue. From the experiments the deformed dimensions and the forging loads are measured and compared with each other by using the simulation coefficients. It is shown that there are good agreements between the model test and the prototype test. Finally, for verifying the availability of the model material technique this mathod is applied to forging of bevel gear product. the good result is obained which can demonstrate that the model material technique is very efficent for estimating or developing a new process.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.180-184
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• 2009

A novel set of experimental test tooling for measuring pulling and holding forces for drawbeads on binders inclined at a wide range of angles is introduced. A mechanical design featuring a single load cell, a male-female draw bead set, translation and rotation degrees of freedom, and a screw-driven clamping system has been incorporated into a standard tensile test machine. On a real time basis, restraining and holding force data with respect to draw-in displacement may be directly downloaded into a PC for data processing. The proposed experimental system represents a significant breakthrough in drawbead simulation technology due to its relatively low cost, clever design, and versatility. The system is shown to yield excellent experimental data suitable for verifying theory and numerical model predictions.

• 인터넷정보학회논문지
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• 제20권6호
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• pp.37-46
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• 2019

A test plan is a high level document detailing objectives, processes, schedules and so on for verifying a developed software. And a test strategy, a component of a test plan, is about how to test software products to guarantee its quality and find bugs in the software in advance. Therefore, establishing effective and suitable test strategies is important for elaborating test processes. However, these tasks are difficult for project managers who write a test plan if they were not trained well in software test processes. And mis-designed test strategies will also mislead entire testing behaviors that testers would do. As a result, there would be a low quality software product in the end. To solve this problem, we propose a new test strategy reuse technique in this paper. By utilizing test plans of already completed software development projects, we lead test planer to reuse suitable and effective test strategies which were used in previous projects. To do so, we evaluate existing test strategies by utilizing ISO/IEC 25010 quality model for evaluating the suitability of test strategies and also use effectiveness metrics for test strategies. And from these evaluations, we predict completeness of new test plan that is written by reused test strategies. It can help the project manager to write an appropriate test plan for the quality characteristics which are selected as objectives for testing and software product. We show the possibility of our approach by implementing a prototype into the existing framework in a case study.

• 항공우주시스템공학회지
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• 제11권1호
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• pp.41-46
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• 2017

소형 다중로터 드론의 동작 실험을 위하여 개발한 장치를 소개한다. 개발한 장치는, 볼 부슁 메카니즘, 이동형 지지대, 그리고 회전판을 적용하여 6자유도 운동이 가능하다. 병렬 처리가 가능한 FPGA기반의 제어기를 사용하여, 가속도와 자이로 센서로 부터 자세를 측정하고 모터 속도를 제어하였다. 다양한 동작을 수행하면서 실험 장치와 제어기의 동작성을 확인하였다. 결론적으로, 개발한 6자유도 실험 장치는 소형 드론 제어를 위한 제어기의 성능 검증을 위해 적합하다.

• 환경영향평가
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• 제20권6호
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• pp.787-795
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• 2011

Noise barrier is generally used with welding of joint rail for railway noise reduction in our country. But the noise barrier for high speed railway has weak point in low frequencies about 315Hz band. In this study, For developing of Interference-type Noise Reduction Device(INRD), acoustic analysis were performed using commercial software. For verifying the improvement in the noise reduction, noise measurement before and after installing of INRD were performed in Anechoic Chamber. From these acoustic analysis and noise measurement, it was known that developed INRD has a good noise reduction performance and can be used efficiently with conventional noise barrier.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1-6
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• 2011

In Korea, high-speed train(HEMU-400X) system with distributed power is being developed, and the highest test speed of this train is 400km/h. This developed the first high-speed train as a distributed power train in Korea, as well as for the development of train system and evaluation system included evaluation technology is needed. Accordingly, a comprehensive and efficient OMS(Overall Measurement System) was build up for verifying the performance of HEMU-400X. By the case study of the G7 and TTX, OMS of HEMU-400X was improved the test performance and maintainability. In particular, the existing Window-based systems has a limit to the control, due to this reason OMS applying enhanced RT(Real-time) system. In this study, compare the advantages and disadvantages of RT systems with Window-based systems, as well as the configuration of the RT systems.

• 한국신뢰성학회지:신뢰성응용연구
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• 제9권1호
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• pp.59-69
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• 2009

LEDs have rapidly replaced old light devices such as incandescent or fluorescent lamps, and have been widely applied in general lighting, signals, automobile, signs and others. Since LEDs are for both indoor and outdoor use, temperature and humidity inevitably affect its reliability. We explain the result of the degradation life test on LEDs, and guide to reliability analysis procedure. Analysis on reliability measures are performed by Weibull++6 program, and a common shape parameter of Weibull distribution on the LED is suggested. Also, we make a description of reliability analysis procedures for the degradation data using collected test data from degradation tests. Reliability analysis procedures are consisted of estimating degradation models and failure time, verifying of distribution and parameters of the distribution, and estimating of reliability measures. Finally, this paper suggests reliability analysis method for light characteristics on LEDs.

• 시큐리티연구
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• 제48호
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• pp.177-206
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• 2016

이 연구의 목적은 위험해석모형을 적용하여 범죄두려움의 영향요인을 검증하는 데 있다. 특히, 기존의 연구들이 위험해석모형에서 제시된 미시적 개인요소를 포함하지 않고 있어 이 연구에서는 미시적 개인요소, 지역사회요소, 범죄 위험의 인지, 범죄두려움 등을 주요 변인으로 포함하였다. 이 연구에 사용된 자료는 형사정책연구원(2012)에서 실시한 '전국범죄피해조사'의 2차 자료를 활용하였으며, 해당 변인들이 범죄두려움에 미치는 개별적인 영향력을 검증하고, 위험해석모형에서 제시된 인과적 경로관계를 규명하기 위해 2단계의 다중회귀분석과 Sobel Test를 실시하였다. 분석결과, 범죄 위험의 인지가 높을수록, 여성일수록, 지역사회가 무질서하다고 인식할수록, 연령이 낮을수록, 범죄피해를 경험할수록, 학력이 높을수록, 소득수준이 높을수록 범죄두려움을 보다 많이 인식하고 있었으며, 그리고 위험해석모형에서 제시된 인과적 경로관계는 학력을 제외하고 모두 유의미하게 제시되었다.

• 한국조리학회지
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• 제17권3호
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• pp.33-46
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• 2011

본 연구는 패밀리 레스토랑의 브랜드 심벌이 브랜드 이미지와 선호도 및 구매의도에 미치는 영향에 관한 것이다. 본 연구 결과, 브랜드 심벌을 시각적 기호로서 기능적 요소, 가치적 요소, 심미적 요소의 3가지 요인이 추출되었고 이중 기능적 요소와 심미적 요소가 브랜드 이미지와 선호도에 영향을 미치는 것으로 나타났으며, 이러한 브랜드 이미지와 선호도는 다시 구매의도에 영향을 미치는 것으로 나타났다. 그리고 소비자들은 브랜드 심벌에 대하여 그림이나 기호의 마크형보다는 기업명이나 브랜드명이 들어간 로고형을 선호하였고 TV광고보다는 옥외광고가 더욱 인지도를 높인다고 응답 하였다. 이러한 결과들을 근거로 향후 브랜드 런칭 시 심벌에 대한 디자인은 앞에서 언급한 로고형 심벌을 우선적으로 고려하고 광고는 어느 한곳에 편중되지 않은 옥외광고와 TV광고가 적절히 혼합하여 사용하여야 할 것이다.