• 한국해양공학회지
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• 제15권1호
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• pp.12-18
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• 2001

This study concentrates on the second-order diffraction problem around circular cylinders in multi-frequency waves. The method of solution is a time-domain Rankine panel method which adopts a higher-order approximation for the velocity potential and wave elevation. In the present study, the multiple second-order quadratic transfer functions are extracted from the second-order time signal generated in random waves, and the comparison with other bench-mark test results shows a good agreement. This approach is directly applicable to prediction of nonlinear forces on offshore structures in random ocean.

• 전기의세계
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• 제45권2호
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• pp.25-31
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• 1996

본 고에서는 국내에서 대리점을 통해 구할 수 있는 전자계 관련 CAE 소프트웨어의 선택에 도움을 주고자, 가장 많이 사용되는 전자계 유한요소(FEM)해석에 관련된 전문 제품을 5개 선정하여 자료를 정리하고 장단점을 비교하였다. 자료의 입수는 우선 국내대리점에게 제품의 요약된 설명과 영문 카탈로그를 요청하였고, 인터넷의 WEB 사이트를 통해 직접 정보를 입수하였다. 독자에게 양해를 구하고자 하는 것은 본 자료가 엄밀한 Bench Mark 테스팅을 거치지 못했다는 것과 모든 소프트웨어를 실제 수행해서 얻은 정보가 아니라는 점이다. 본 기사의 의미는 소프트웨어의 순위가 아니라 비교적 정리된 데이터로서 선택을 위한 참조자료 정도로 생각해 주기 바란다.

• Environmental Engineering Research
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• 제13권3호
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• pp.119-124
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• 2008

Ammonia is an inorganic compound that may cause severe odor problem. In this study the effectiveness of applying natural neutralizer to destroy and remove the odor-causing compound from gas streams was studied. Experimental result evaluated with a bench-scale apparatus via the neutralization of gas phase. This indicates that the natural neutralization depends on the gas concentration, gas residence time, temperature and pH. Removal efficiency of ammonia from gas stream was achieved by 95% using theconvection in the packed bed. This study proved the chemical neutralization technology was effective for controlling inorganic odor-causing compound.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 추계학술대회논문집; 한국과학기술회관; 6 Nov. 1997
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• pp.358-363
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• 1997

The Operational Deflection Shape designates the motion pattern by which a structure vibrates under a specific operating condition. Modal Analysis is usually tested under test bench, but Operational Deflection Shape can be measured directly under real operating condition. It provide useful information for trouble-shooting and aid understanding and evaluation of the absolute dynamic behaviour of a machine or component. In this paper, It is analysed Excavator Upper Frame using Operating Deflection Shape.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 추계학술대회논문집; 한국과학기술회관; 6 Nov. 1997
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• pp.339-344
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• 1997

Samsung Ltd. has developed a new-type cab mount for specific use on construct ion machinery subjected to strong vibration and multi-directional impact force. These all make it possible to achieve an excellent damping effect over a wide frequency range against large amplitude vibration as well as excellent insulation against small-amplitude vibration. This new mount make lower vibration and noise levels while increasing riding comfort at the same time. Characteristics of Cab mount were optimized through computer simulation, advanced bench testing, ODS testing, and a real equipment offroad testing.

• 산업융합연구
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• 제8권2호
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• pp.41-60
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• 2010

Unlike ordinary business. it prioritizes employment over profit. So it is important to Identify the know-how of prosperous social enterprises and apply it to other cases for social enterprises to survive and be competitive. Bench-marking is not just imitation but recreation process. So it is the best management tool for distribution of successful examples.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권6호
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• pp.441-448
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• 2000

Experimental work was carried out on nitrogen and phosphorus removal from real wastewater using a bench-scale SBR process. The phosphorus removal was stable and the phosphorus concentration remaining in the reactor was maintained within 1.5ppm, regardless of the addition of an external carbon source. In the case of nitrogen, an external carbon source was necessary for denitrification. The effect on denitrification with the addition of various carbon sources, such as glucose, methanol, acetate, and propionate, was also investigated. Acetate was found to be the most effective among those tested in this study. When 100ppm (theoretical oxygen demand) of sodium acetate was added, the average rate of denitrifiaction was 2.73mg NO$_3$-N (g MLSS)(sup)-1 h(sup)-1, which was ca. 4 times higher than that with the addition of 200 ppm of methanol. The phosphorus and nitrogen concentrations were both maintained within 1.5ppm by the addition of an appropriate amount of a carbon source during a long-term operation of the SBR. The mathematical modeling was performed using Monod kinetics, other microbial kinetics, mass balances, and stoichiometry. The modeling was found to be useful for predicting the SBR operation and optimizing the HRT.

• 통상정보연구
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• 제16권4호
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• pp.55-75
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• 2014

본 연구는 국내 ICT 제조업과 서비스업의 경쟁력 강화를 위한 기초 연구로서 효율성과 생산성 추이 및 생산성의 결정요인을 분석하는 것을 목적으로 하였다. 구체적으로 본 연구는 ICT산업의 효율성 분석을 위해 ICT 제조업 23개 업종과 ICT 서비스업 18개 업종에 대하여 2007년부터 2011년까지 5년간 규모의 수익불변을 가정한 DEA(Data Envelopment Analysis)의 CCR모형과 규모의 수익가변을 가정한 BCC모형을 통해 기술효율성과 순수기술효율성의 정태적 효율성을 살펴보고, 기술효율성에 대한 DEA/Window 분석과 Malmquist 생산성 지수를 이용하여 동태적 효율성을 분석하였다.

• 디지털융복합연구
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• 제13권8호
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• pp.449-455
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• 2015

공공 디자인에서 공공성의 실현 여부를 판단하는 데는 해당 디자인의 수행 과정과 방향성 등 다양한 측면이 고려 돼야한다. 공공 디자인이란 공공성을 갖춘 디자인이다. 그럼에도 무엇보다도 사용자에게 미적관심을 유발시키는 것이 우선이다. 한편, 디자인의 편의성은 심미성을 높이는데 기여하기도 한다. 연구자가 시도한 융복합적인 인터랙션을 적용한 공공디자인은 공공장소에서 사적 영역의 보호와 같은 공공성을 체험토록 기획하였다. 꽃술을 모티브로 하여 심미성에 바탕을 두면서 기능적으로는 뉴미디어의 인터랙션을 활용한 이 공용 벤치 디자인 제안은 사용자의 미적 반응에서 시작하여 편의성과 쾌적함 나아가 사용자가 체험하는 공공성의 경험이 공공 디자인의 의미와 가치판단을 가능하게 하는 요소임을 제시한다.

• International Journal of Aeronautical and Space Sciences
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• 제17권3호
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• pp.442-453
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• 2016

A significant source of vibration in helicopters is the main rotor system, and it is a technical challenge to reduce the vibration in order to ensure the comfort of crew and passengers. Several types of passive devices have been applied to conventional helicopters in order to reduce the vibration. In recent years, helicopter manufacturers have increasingly adopted active vibration control systems (AVCSs) due to their superior performance with lower weight compared with passive devices. AVCSs can also maintain their performance over aircraft configuration and flight condition changes. As part of the development of AVCS software for light civil helicopter (LCH) applications, a test bench is constructed and vibration control tests and simulations are performed in this study. The test bench, which represents the airframe, is excited using a pair of counter rotating force generators (CRFGs) and a multiple input single output (MISO) AVCS that consists of three accelerometer sensors and a pair of CRFGs; a filtered-x least mean square (LMS) algorithm is applied for the vibration reduction. First, the vibration control tests are performed with uniform sensor weights; then, the change in the control performance according to changes in the sensor weight is investigated and compared with the simulation results. It is found that the vibration control performance can be tuned through adjusting the weights of the three sensors, even if only one actuator is used.