• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.140-146
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• 2008

A friction damper is installed in the passenger car driveline in order to dissipate the torsional vibration energy. The frictional damping hysteresis has considerable influences on the driveline vibration characteristics and, therefore, it is one of the most important parameters in the damper design. To investigate the hysteresis effects on the driveline vibration, a dynamic model of the passenger car driveline with manual transmission has developed, and simulations were executed on the several different driving conditions for various hysteresis values. To verify the model, vehicle tests are preformed and the test data were compared with the simulations results. The simulation and test results show good agreements and the model could be used to determine the optimal hyteresis values in early design stage of the damper.

• Nuclear Engineering and Technology
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• v.3 no.2
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• pp.59-64
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• 1971

This paper presents an approach to control that if a result of modern control theory, and is based on tile control philosophy of feeding back all tile state variable through constant gain frequency independent elements. The values of these elements or feedback coefficients are determined by equating like coefficients of the desired system transfer function to the transfer function of the system containing the unspecified coefficient s. This application of modern control law is a simple design method depending on feedingback all the system variables for reactor control and it is particuraly amenable to the control of Pressurized Water Reactor.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.3
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• pp.325-329
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• 1997

The optimum temperature and pH for growth and hydrogen evolution of the organism were observed at 30-35$^{\circ}C$, and around pH 7.0, respectively. The efficiency of various sugars and organic acids on hydrogen evolution as electron donors by the organism was examined. Among them, higher rates of hydrogen evolution were observed with sugars such as glucose or fructose and organic acids such as alate or pyruvate. From the result, it was evident that Rhodobacter sphaeroides KS56 had a great capacity of utilizing various kinds of reduced carbon compounds as electron donors.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2658-2660
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• 2000

본 논문은 주파수역에서의 모델매칭을 이용하여 강인한 성능의 PID 제어기 튜닝법을 제안하였다. 이를 이용하여 부하토크 외란에도 강인한 성능의 BLDC 모터의 속도제어기를 설계하였다. 부하토크 외란이 존재하여도 주어진 기준명령을 강인하게 추종하도록 $H_{\infty}$ 제어를 이용하여 속도제어기를 설계한 후, 설계할 PID 제어계의 루프 전달함수와 설계된 $H_{\infty}$ 제어계의 루프 전달함수간의 오차가 주파수역에서 최소가 되도록 PID 제어기 파라미터를 튜닝하였다. BLDC 모터의 속도제어 시뮬레이션을 통하여 설계된 강인 PID 제어기의 성능을 평가하였다.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.46-50
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• 1986

Experiments with particulate fractions of Acinetobacter sp. 1 revealed that coeuzyme $Q_{10}$ is not the physiolohical electron acceptor, and that cytochromes of a, b, c, and o types are found in cells grown with carbon monoxide (CO) as the sole source of carbon and energy. It was found that cytochromes of b and o types, but not the a and c types, are functional in CO oxidation. Nicotinamide adenine dinucleotide (phosphate) is not involved in CO oxidation.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.2
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• pp.57-68
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• 1991

In this study, to analyse the dynamic characteristics of a machine-tool spindle system, the spindle is mathematically represented by a Timoshenko beam including the internal damping of beam material, and each bearing by four bearing coefficients; stiffness and damping coefficients in moment and radial directions. And the dynamic compliance of the system is calculated by introducing the transfer matrix method, and the complex modal analysis method has been applied for the modal parameter identification. The influence of the bearing coefficients, material damping factor and bearing span on the dynamic characteristics of the system is parametrically examined.

• Annual Conference of KIPS
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• 2015.10a
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• pp.1665-1667
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• 2015

본 논문은 운전자의 안전운전 지원을 위하여 실세계 자동차 외부에 위치한 카메라와 RADAR 센서들에서 취득하는 정보들을 통하여 가상세계에 운전 환경의 실세계를 그대로 재현하여 활용하는 기술을 소개한다. 이 기술은 운전상황의 제한된 인터페이싱 상황과 짧은 주의집중 시간에 모든 정보를 정확하게 전달하기 위하여, 직관적이고 효과적 전달이 가능한 복합 멀티미디어 - 동영상 및 간단한 텍스트 정보 - 의 형태를 활용한다. 이러한 융합 미디어 기반 운전정보 지원 서비스는 실시간 운전 상황에 대한 운전자의 이해와 대응력을 높여 안전운전에 기여할 수 있을 것이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.5
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• pp.451-457
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• 2006

Conjugate heat transfer (CHT) is the simultaneous, coupled heat transfer within a fluid and an adjoining solid, and the interface treatment plays an important role in its analysis, particularly when using unstructured grid system. In the present paper a new solid-fluid interface treatment in CHT analysis is presented and applied to two typical CHT problems, i.e. natural convections in both concentric thick-walled cylinders and cavity with a centered solid body. The present interface treatment for unstructured mesh clearly demonstrates the same accuracy and robustness as that for typical structured mesh.

• Annual Conference of KIPS
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• 2011.04a
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• pp.1173-1175
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• 2011

국내의 인구는 고령화와 함께 의료비 지출이 늘어나는 것은 혈압이나 당뇨와 같은 만성질환자 환자 비중이 높아졌기 때문이며 의료비의 절감 및 건강관리 향상을 위하여 본 연구에서는 스마트폰 점유율이 높은 안드로이드 OS를 기반으로 하여 건강관리 콘텐츠를 제공 하는 앱을 설계 하였다. 설계한 앱은 혈압계, 심전도 기기, 혈당계, 전자청진기 등을 이용하여 사용자가 자신의 건강상태를 안드로이드 기기에 전달하여 서버에 저장 하는 구동절차를 가지고 있으며, 서버에서는 LOG 정보를 이용하여 사용자가 원하는 서비스 요청을 통하여 사용자에게 맞는 건강관리 콘텐츠를 전달한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.11
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• pp.1105-1111
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• 2015

The exhaust system is one of the major sources of vibrations, along with the suspension system and engine. When the exhaust system is connected directly to the engine, it transfers vibrations to the vehicle body through the body mounts. Therefore, in order to reduce the vibrations transmitted from the exhaust system, the vibration characteristics of the exhaust system should be predicted. Thus, the dynamic characteristics of the bellows, which form a key component of the exhaust system, must be modeled accurately. However, it is difficult to model the bellows because of the complicated geometry. Though the equivalent beam modeling technique has been applied in the design stage, it is not sufficiently accurate in the case of the bellows which have complicated geometries. In this paper, we present an improved technique for modeling the bellows in a vehicle. The accuracy of the modeling method is verified by comparison with the experimental results.