• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2005년도 연구개발 발표회 논문집
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• pp.467-472
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• 2005

Characteristics of a Modified regenerative cycle gas turbine has been investigated. In the cycle, the turbine expansion is divided into two parts and the regenerator locates between them. Two types of mechanical design are assumed: two-shaft and single-shaft. In particular, optimal pressure ratio division between the high and low pressure turbines is evaluated for the single shaft configuration. The part load analyses have been carried out with the aid of off-design models. In addition to the general fuel only control, a variable speed control is assumed as the part load operating strategy of the single shaft configuration. Obvious advantage with the alternative cycle is observed in the variable speed operation of the single shaft design.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.469-477
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• 1996

In order to maintain a constant ratio between the ground wheel and fed shaft of planters, a feedback control unit was designed to drive the feed shaft in proportional to the ground speed. The fifth wheel was used as a ground speed sensor for the control unit. Using this control unit a feed shaft driving system was developed and tested both in the laboratory and field to evaluate it performance . The test results showed that the system drove the feed shaft in proportional to the ground speed in the normal planting speed range of 0.5 -0.8m/s with an error of less than 5%.

• 한국소음진동공학회논문집
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• 제19권3호
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• pp.274-281
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• 2009

The carbon fiber epoxy composite material and aluminum have many advantages over other materials because of their high specific stiffness and good fatigue characteristics. Basically, the propeller shaft of automobile requires bending frequency of higher than 2,700 Nm and high natural frequency of higher than 9,200 rpm occurred by fast revolution. For this reason, natural frequency and torsion torque characteristics of hybrid shaft was studied in variation of its outer-diameter and thickness. Vibration and torque characteristics of hybrid shaft were compared by torsion tester, natural frequency experiments and FE analysis. Designed hybrid shaft satisfied its vibration and torque characteristics when its outer-diameter was 60 mm and thickness was 5 mm. Therefore, hybrid material enables to manufacture one piece structure hybrid propeller shaft rather than current two piece structure.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.429-430
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• 2006

To estimate the fatigue life of flange-shaft assembly, fatigue test for flange material and bending fatigue test for flange-shaft assembly were conducted. Also, finite element analysis for flange-shaft assembly was conducted. Then, we have changed the obtained P-N curve to S-N curve using the finite element analysis results which were stress values at the location of fracture. The S-N curve of flange material itself was almost consistent with that of flange-shaft assembly, so it seems that the fatigue life of flange-shaft assembly could be estimated by using S-N curve for flange material and the stress at the location of fracture calculated by finite element methods.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.768-770
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• 2014

A shaft of a reciprocating compressor receives bending force by piston, which makes movement of the shaft. The movement of the shaft affects durability and becomes a source of noise. In this paper, a cylinder is modeled by considering motion of a suction and discharge valve. The journal bearing is modeled by Bernoulli's equation. The trajectory of shaft which is considered cylinder and journal bearing can be calculated by finite element method. It will help a design of shaft to increase durability and reduce noise.

• Journal of Power Electronics
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• 제14권5호
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• pp.859-865
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• 2014

This study presents an electromagnetic model for predicting shaft voltages in a 2-pole field-excited synchronous generator. After the first observations on shaft voltages were made more than a century ago, extensive work has been conducted on eliminating, mitigating, and integrating the aforementioned phenomena. Given that emphasis has been placed on modeling shaft- and bearing-induced voltages in AC motors driven by variable frequency drives, similar efforts toward a model that is dedicated to generators are insubstantial. This work endeavors to improve current physical interpretation and prediction methods for shaft-induced voltages in generators through semi-analytical derivation. Aside from the experimental validation of the model, investigations regarding the behavior of shaft voltages under varying machine complexities and operating conditions clarify previous uncertainties regarding these phenomena. The performance of the numerical method is also assessed for application in eccentricity fault diagnosis.

• Smart Structures and Systems
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• 제2권1호
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• pp.47-60
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• 2006

Bi-spectrum is a tool in the signal processing for identification of non-linear dynamic behvaiour in systems, and well-known for stationary system where components are non-linearly interacting. Breathing of a crack during shaft rotation is also exhibits a non-linear behaviour. The crack is known to generate 2X (twice the machine RPM) and higher harmonics in addition to 1X component in the shaft response during its rotation. Misaligned shaft also shows similar such feature as a crack in a shaft. The bi-spectrum method has now been applied on a small rotating rig to observe its features. The bi-spectrum results are found to be encouraging to distinguish these faults based on few experiments conducted on a small rig. The results are presented here.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.717-724
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• 2002

To investigate the behavior of air-shaft and existing tunnel by excavating the small-diameter shaft into the existing tunnel, prototype air-shaft was constructed and analyzed in this study. Geotechnical characterization was conducted by boring and rock cores obtained were tested in the laboratory. Field monitoring including radial and tangential stresses and displacements was conducted with the 3-dimensional numerical analysis of prototype air-shaft. Results of field monitoring were compared with the numerical results. The results showed that maximum displacement of 2.11mm and maximum tangential stress of 54.0 kg/$\textrm{cm}^2$ were obtained during shaft excavation near the right shoulder of the existing tunnel. The comparison of these field measurements with 3-dimensional numerical analysis showed that much more higher stress was measured during excavation compared to the numerical results even though the trends of stress and displacement were similar.

• 한국기계기술학회지
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• 제20권6호
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• pp.751-756
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• 2018

A study on the weight reduction of a motor shaft in electric vehicle by using optimum design technique was carried out. The structural analysis of a motor shaft was performed by using ANSYS to investigate the structural safety. We also used HEEDS to find the optimal hollow shaft thickness. When the material of the hollow shaft is changed to SCM822H by using ANSYS 14.5 and HEEDS MDO, the weight could be reduced by about 53 % compared to the conventional solid one. From this study, the optimized dimensions of a hollow shaft were determined for light weight design.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2021년도 춘계학술대회
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• pp.216-219
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• 2021

친환경선박법에서 샤프트제너레이터(shaft generator)는 친환경선박 해당 기자재로 정부와 선주의 높은 관심을 보이고 있다. 하지만, 선박에서 신기술을 적용하기 위해서는 높은 신뢰성을 요구하고 있으며, 이를 위한 검증 방법으로 HILS(hardware in loop system)테스트를 사용한다. 이에, 본 논문에서는 샤프트제너레이터를 적용한 터그보트의 HILS 테스트를 위해, 샤프트제너레이터를 모델링하고 시뮬레이션 하였다. 시뮬레이션을 통해, 시나리오에 따라 샤프트제너레이터의 충방전이 동작하는 것을 검증하였다.