• 한국자동차공학회논문집
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• 제10권1호
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• pp.162-167
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• 2002

An automotive wheel bearing is one of the most important components to guarantee the service life of a passenger car. The endurance life of a bearing is affected by many parameters such as material properties, heat treatment, lubrication conditions, temperature, loading conditions, bearing geometry, internal clearance and so on. In this paper, we analyze the relation between loads and deformations of wheel bearing units. On the basis of it, we calculate the endurance life of wheel bearing units and suggest a method to determine the initial contact angle to achieve a maximum endurance life with considering stress concentration.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.670-673
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• 2002

Automotive wheel bearings are one of the most important components to guarantee the service life of a passenger car. The endurance life of a bearing is affected by many parameters such as material properties, heat treatment, lubrication conditions, temperature, loading conditions, bearing geometry, internal clearance and so on. In this paper, we analyze the relation between loads and deformations of wheel bearing units. On the basis of it we calculate the endurance life of wheel bearing units and analyze the contribution of bearing geometric parameters on the endurance life by using Taguchi method.

• 한국공작기계학회논문집
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• 제12권1호
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• pp.38-44
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• 2003

In this study, endurance limit and fatigue behavior of load carrying fillet welded cruciform joints depending on commonly used welding methods such as SMAW, SAW, MIG and FCAW are investigated. In respect of endurance limit SMAW specimen showes highest result, and then MIG, SAW, FCAW in descending order. However, SMAW specimen showes lowest crack growth rate and it followed by MIG, FCAW, SAW. By these results, it is needed to use SMAW or MIG welding methods for welding structures with small welding capacity and SAW or FCAW methods for large welding structures with respect to economic benefits and operation efficiency of welding. It was also shown fatigue crack growth rate was more influenced by the strenght of welding materials than the endurance limit of welding materials.

• 전기학회논문지
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• 제63권8호
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• pp.1146-1151
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• 2014

The equipment in ships and railway vehicles are continuously exposed to vibration, and its durability is very important. Therefore, consumers require the verification of the performance of equipment via standardized tests under the given environments to improve and stabilize the performance. In this study, a durability improvement and stabilization plan was proposed, which included the exploratory vibration test, variable frequency test and endurance test for the electrical equipment according to the vibration environment. It is expected that this study results will improve the technological competitive power of the ship and railway-related manufacturers and contribute to the equipment development and export.

• 재활복지공학회논문지
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• 제5권1호
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• pp.11-15
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• 2011

본 논문은 사함의 근육에서 발생하는 근전위 신호에 의해서 제어되는 근전의수의 성능에 대한 시험방법을 제안한 것이다. 근전의수는 기계적인 의수, 근전위 신호를 측정하는 표면 근전위 센서, 제어시스템, 그리고 충전용 배터리로 구성되어 있다. 상용화 된 근전의수를 가지고 파지 내구성을 시험한 결과 소음과 파지력은 큰 차이가 없었다. 제안된 시험방법은 내구성 시험을 통하여 근전의수의 신뢰성을 검증하였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.226-227
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• 2005

In this study, it was investigated about endurance and fatigue crack propagation rate of according to welding methods of SMAW and FCAW commonly using for welding structures in present. Endurance limits carried out highly in the order of SMAW, FCAW and fatigue crack propagation rate out lowly in the order of SMAW, FCAW. By these results, it is needed to used SMAW welding methods for welding structures with small welding capacity and FCAW methods for large welding structures after consideration about economic gains and operation efficiency of welding. Fatigue crack propagation rate is more effected by strength of welding materials than endurance limit of welding materials according to welding methods..

• 한국정밀공학회지
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• 제20권10호
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• pp.164-168
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• 2003

An automotive wheel bearing is one of the most important components to guarantee the service life of a passenger car. The endurance life of a bearing is affected by many parameters such as material properties, heat treatment, lubrication conditions, operating temperature, loading conditions, bearing geometry, the internal clearance of bearing and so on. In this paper, we analyze the relation between loads and deformations of wheel bearing units for optimal bearing unit design. On the basis of it, we calculate the endurance life of w heel bearing units and analyze the contribution of bearing geometric parameters on the endurance life by using Taguchi method.

• 보건교육건강증진학회지
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• 제21권4호
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• pp.99-108
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• 2004

The purpose of this study was to examine the relationship between physical fitness, and physical and psychological stress of females. The subjects of this study were 139 adult women, without a specific medical illness. The stress level was evaluated by Derogetis's checklist-90-Revision symptom of physical and psychological stress (Cronbach's a=0.88, 0.87). The physical fitness factors in this study were cardiopulmonary endurance, muscle endurance, muscle strength, power, agility, and flexibility. To analyze the data to examine the relationship between the physical and psychological stress, and physical fitness, correlation analysis was applied. The findings of this study were as follows. First, among the physical fitness factors, cardiopulmonary endurance, along with muscle strength and power had significant relations with physical stress (p<.01). Second, among the physical fitness factors, cardiopulmonary endurance showed a significant relation with psychological stress (p<.05).

• 한국안전학회지
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• 제22권3호
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• pp.1-6
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• 2007

In order to evaluate fatigue endurance for the rocker arm of a diesel engine, stress measurements were performed using the strain gages attached near the neck, where is one of the most critical region in the rocker arm, in variation of the engine speed. The fatigue life experiments were carried out on miniature specimens from the rocker arms. For evaluating the fatigue endurance of the rocker arm, the S-N data were compared with the stress analysis results through FEM analysis of the rocker arm. The effective stress of the neck region was determined 17.7MPa through FEM analysis of the rocker arm. Conclusively, on the basis of fatigue limit, the rocker arm has a safety factor of 2.8 or 3.4 from the stress measurement or FEM results, respectively.

• 생명과학회지
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• 제17권6호통권86호
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• pp.867-872
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• 2007

The aging is related to numerous changes in our body system which declines functional ability. The functional ability in advanced age can be evaluated by the 4 components of fitness (cardiorespiratory endurance, muscular strength and endurance, flexibility and body composition). The understanding and knowledge of changing 4 components of fitness and the role of exercise on the process of aging is of paramount importance. Despite exercise and physical activity have been shown to delay the process of aging, the exercise guidelines and recommendations for old adults are not well published. This review is to presents the age-related changes in each component of fitness and to present current guidelines and recommendations for exercise in older adults.