• 한국지리정보학회지
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• 제10권4호
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• pp.14-21
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• 2007

일반적으로 수심측량은 해저면의 수심을 측량하는 방법이다. 해도상에 표시되는 모든 수심은 200Khz 주파수를 사용하는 에코사운더를 사용하여 측정된다. 이 연구에서는 부니층의 두께조사를 위해 이중 주파수인 33Khz와 200Khz를 사용하였다. 준설구역상에 부니층의 물량을 조사하는 방법을 알게 되며 부니층의 유무에 대한 검증을 위해 RI 테스트가 측량 후에 수행된다.

• 상하수도학회지
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• 제22권3호
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• pp.351-358
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• 2008

The modified in-line mixer which was suggested in this study for small water treatment facilities was evaluated on the performance of coagulation. For the objectives of this research, computational fluid dynamics(CFD) simulation was applied for analysis of flow characteristics within the modified in-line mixer. For verifying the results of CFD simulation, wet tests for the pilot plant were conducted. The wet test was to measure the actual coagulant dispersion distribution on the overall cross-section at a distance of 5.5D from the chemical injection point. From the results of CFD simulation and wet test, it was shown that the coagulant dispersion within the modified in-line mixer was occurred more uniformly than within the existing PDM(Pump diffusion Mixer). The results have confirmed the modified in-line mixer had several advantages compared with the existing PDM in terms of dispersion efficiency.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2600-2608
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• 2011

The dynamic stability of railway vehicle has been one of the important issues in railway safety. The dynamic simulator has been used in the study about the dynamic stability of railway vehicle and wheel/rail interface. Especially, a small scale simulator has been widely used in the fundamental study in the laboratory instead of full scale roller rig which is not cost effective and inconvenient to achieve diverse design parameters. But the technique for the design of the small scale simulator for the fundamental study about the dynamic characteristics of the wheel-rail system and the bogie system has not been well developed in Korea. Therefore, the research about the development of the small scale simulator and the bogie has been conducted. As this paper, To predict the dynamic behavior of railway vehicle, we studied running stability test of 1/5 scaled bogie that similarity laws is applied using small scale derailment simulator. For the operation of the small scale derailment simulator, it is required to investigate the performance and characteristics of the system. This could be achieved by a comparative study between an analysis and an experiment. This paper presented the analytical model which could be used for verifying of the test results and understanding of the physical behavior of the dynamic system comprising the small scale bogie and the simulator.

• International Journal of Fluid Machinery and Systems
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• 제8권4호
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• pp.221-229
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• 2015

For efficient design process of regenerative blower, the present study provides new generalized pressure and leakage flow loss models, which can be used in the performance analysis method of regenerative blower. The present performance analysis on designed blower is made by incorporating momentum exchange theory between impellers and side channel with mean line analysis method, and its pressure loss and leakage flow models are generalized from the related fluid mechanics correlations which can be expressed in terms of blower design variables. The present performance analysis method is applied to four existing models for verifying its prediction accuracy, and the prediction and the test results agreed well within a few percentage of relative error. Furthermore, the present performance analysis method is also applied in developing a new blower used for fuel cell application, and the newly designed blower is manufactured and tested through chamber-type test facility. The performance prediction by the present method agreed well with the test result and also with the CFD simulation results. From the comparison results, the present performance analysis method is shown to be suitable for the actual design practice of regenerative blower.

• 한국구조물진단유지관리공학회 논문집
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• 제18권1호
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• pp.93-100
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• 2014

해수중 환경에서 콘크리트 구조물 내에 매립된 철근은 용존산소의 부족으로 부식이 잘 발생하지 않는다. 이 때문에 해수중 환경의 부식촉진시험은 전기화학적인 방법으로 실시되어, 실제 부식 메커니즘과 맞지 않고 장기거동과의 상관성 도출도 어려운 실정이다. 본 연구에서는 해수중 환경에서의 부식촉진시험법을 정립하기 위해 온도와 염화물농도를 주된 변수로 부식촉진시험을 실시하였다. 부식의 발생 유무는 갈바닉 전위측정법과 반전지전위법을 통한 철근부식모니터링 결과로 판단하였다. 부식촉진시험 결과 온도의 영향이 가장 지배적이라고 평가되었다. 염화물량은 시험 시편의 깊이별 염화물 농도를 측정하였다. 동일한 조건으로 FEM 내구성 해석 프로그램인 DuCOM을 통해 염화물침투 해석을 실시하여 입증하였다. 또한, 인공해수 침지 조건에 따른 용존 산소량은 실험을 통해 구했으며 이를 통해 부식촉진시험 결과의 타당성을 검증하였다.

• 자동차안전학회지
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• 제11권1호
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• pp.7-16
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• 2019

There are trying to reduce damage from automobile accident in many countries. In many automobile companies, there have been active study on development of ADAS (Advanced Driver Assistance Systems) for commercialization, in order to reduce damage from automobile accident. ADAS is the system providing convenience and safeness for drivers. Generally, ADAS is composed of ACC (Adaptive Cruise Control), LKAS (Lane Keeping Assist System), and AEB (Autonomous Emergency Braking). AEB of the ADAS, it is an autonomous emergency braking system and it senses potential collide and avoids or degrades it. Therefore AEB plays a significant role in reducing automobile accident rate. However, AEB safety evaluation method is not established not yet. For this reason, this study suggests safety evaluation scenarios with adding cut-in, sensor malfunctioning scenario that scenario domestic street conditions considered as well as original standard AEB scenario of Euro NCAP for establishment of safety evaluation method of AEB. And verifying validity of suggested scenario by comparing the calculated values of the theoretical formulas presented in the previous study with results of the actual vehicle test.

• 한국산업융합학회 논문집
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• 제26권4_2호
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• pp.639-648
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• 2023

In modern society, UAM (Urban Air Mobility) transportation system is being developed as an alternative to urban traffic congestion and environmental problems, and electric vertical take-off and landing (eVTOL) is a combination of vertical take-off and landing function and electric power. It is attracting attention as an innovative next-generation transportation method as an eco-friendly alternative that reduces noise and air pollution by providing efficient mobility within the city. Since eVTOL development requires designing and implementing airframes suitable for various mission purposes, the power system needs to be developed as a platform concept before airframe development. In this study, we empirically proposed a test bench concept equipped with a stable power supply and an efficient control system, essential in developing a power platform with a combined function in the form of a fuselage and module type specialized for various mission purposes. The proposed drivetrain platform test bench consists of a system verifying the stable take-off and landing software and a power platform adjusting the motor's thrust. It will serve as a verification system that can be developed.

• 한국항공우주학회지
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• 제35권10호
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• pp.948-956
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• 2007

항공기를 개발함에 있어 기체를 구성하는 계통의 성능이 항공기 요구도를 만족하는 수준으로 발휘되는지 확인하는 것이 중요하다. 특히, 엔진을 포함한 추진계통은 항공기를 구성하는 구성품 중 중요한 계통으로서, 추진계통과 기체와의 통합성을 검증하는 것이 항공기 개발에 있어 필수적 요소이다. T-50 고등훈련기 체계개발 시 추진계통 검증을 위해 엔진 공중재시동 시험 및 엔진 축마력 시험, backup throttle기능 시험 등의 다양한 비행시험을 수행하였으며, 이와 같은 항목의 비행시험을 통하여 T-50 고등 훈련기의 추진계통이 기체에 적합하게 설계/장착되었음을 확인하였다. 본 논문에서 추진계통 비행시험 항목에 대한 설명 및 시험 절차, 결과를 제시하였으며, 본 논문의 내용이 차후 타 항공기 개발 시 추진계통 관련 비행시험을 준비하는 과정에서 참고가 될 수 있을 것으로 기대한다.

• 한국전자통신학회논문지
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• 제15권3호
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• pp.389-396
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• 2020

좋은 품질의 제품을 얻기 위해서는 제품 자체에 대한 품질 적합성 검사 이전에 생산 및 시험 관련 설비에 대한 적절한 검증이 반드시 선행되어야 한다. 다양한 생산 및 시험 관련 설비 중에서도 ATE는 오늘날 자동차산업, 항공·우주산업, 반도체산업과 같은 민간분야 뿐만 아니라, 방위산업의 군수품 생산 및 성능시험에도 활발히 사용되고 있다. 본 논문은 다양한 방법을 활용하여 군용 FM 무전기 세트의 자동시험장비 인 ATS에 대해 체계적으로 설계 적합성 검증을 실시 한 결과를 다루고 있으며, 군수품 ATE에 대한 설계 적합성 검증 절차가 명문화 되어있지 않은 현 시점에 좋은 참고자료가 될 것으로 기대된다.

• 한국군사과학기술학회지
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• 제15권1호
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• pp.66-74
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• 2012

The virtual target signal generator was developed to verify the shipborne tracking radar performance. It was used to DRFM(Digital RF Memory) method to generate the virtual moving targets. The target signal includes Doppler shift and RCS according to the target motion. And the signal generator can make jamming signal and clutter to test shipborne radar performance at real environmental condition. This paper described the functional diagram and the hardware configuration items to meet the test requirements for the tracking radar. And it showed the critical design points for the sub-systems. The signal generator which was developed in this paper shared the operational information of the radar with the radar command and control part. To test the frequency agility of the radar, it had the local oscillator which could do high speed frequency switching according to radar information. By communicating between the signal generator and the radar command and control part, the local oscillator of signal generator could be controlled every pulse. It reduced the instantaneous bandwidth of signal generator and minimized the spurious. So it lowered the probability of generating wrong targets.