• Tribology and Lubricants
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• 제26권5호
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• pp.263-271
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• 2010

The rollers of cylindrical roller bearing are axially profiled to relieve high edge stress concentration caused by mainly their finite length and by misalignment. In this paper, a numerical analysis is carried to study the EHL of misaligned (tilted) rollers with axially profiled ends. Using a finite difference method with non-uniform grids and the Newton-Raphson method, the highly nonlinear EHL problems are systematically solved. Physically consistent solutions are obtained for moderate load, material parameters and very small misalignment. For different misalignment angles, contours and sectional plots of pressure and film shape near both edge regions are compared. The asymmetric pressure distributions and film shapes show that the EHL results of finite line contacts are highly dependent upon very small amounts of roller misalignment. Especially, the effect of misalignment on the EHL pressure distribution is much higher than the film shapes.

• Tribology and Lubricants
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• 제29권6호
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• pp.353-359
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• 2013

The rollers and/or races in cylindrical and tapered roller bearings should be profiled to relieve high edge stress concentrations caused by their finite lengths and misalignment. In this study, a numerical analysis was performed to investigate the elastohydrodynamic lubrication (EHL) of a Lundberg profile-type cylindrical roller. A finite difference method with fully nonuniform grids and the Newton-Raphson method were used to present detailed EHL pressure distributions and film shapes, as well as the variations in the minimum and central film thicknesses with the profile modification coefficient. In the Lundberg profile, the maximum pressure and minimum film thickness always occurred near the edges. Proper modification of the Lundberg profile considerably increased the minimum film thickness.

• 한국세라믹학회지
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• 제34권5호
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• pp.535-543
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• 1997

The surface of SiC particles were partially oxidized to produce SiO2 layers on the SiC particles to prepare Al2O3/SiC composite by formation of mullite bonds between the grains of Al2O3 and SiC during sintering at 1$600^{\circ}C$. This process is considered to enable the sintering of Al2O3/SiC composite at lower temperature and also to relieve the stress, produced by thermal expansion mismatch between Al2O3 and SiC. In fact, Al2O3/SiC composite prepared by oxidation of SiC was observed to be more effectively sintered and densified at lower temperature. Maximum density, flexural strength and microhardness were obtained with 5.65 vol% of mullite content in Al2O3/SiC composite.

• International Journal of Concrete Structures and Materials
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• 제9권3호
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• pp.337-343
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• 2015

Previous studies have shown that the drying shrinkage of recycled aggregate concrete (RAC) is greater than that of natural aggregate concrete (NAC). Drying shrinkage is the fundamental reason for the cracking of concrete, and tensile creep caused by the restraint of drying shrinkage plays a significant role in the cracking because it can relieve the tensile stress and results in the delay of cracking occurrence. However, up till now, all research has been focusing on the compressive creep of RAC. Therefore, in this study, a uniaxial restrained shrinkage cracking test was executed to investigate the tensile creep properties caused by the restraint of drying shrinkage of RAC. The mechanical properties, such as compressive strength, tensile splitting strength, and Young's modulus of RAC were also investigated in this study. The results confirmed that the tensile creep of RAC caused by the restraint of shrinkage was about 20-30 % larger than that of NAC.

• 동의신경정신과학회지
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• 제15권1호
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• pp.1-7
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• 2004

Object : The purpose of this study is difference between western medicine and oriental medicine in tension headache. Methods : A literature study on the tension headache was performed. The cause, symptoms, relationship with other diseases, pathology and treatment of oriental and western medicine were investigated. Conclusion : In western medicine, tension headache is mainly caused by emotional stress, tension of head and neck musculatures. Treatments include medication, psychologic care, alteration of habits and biofeedback. Removal of muscle tension is of main interest in western medicine. In oriental medicine, tension headache is classified into internal and external problem. The imbalance of organs of spleen, liver and kidney causes headache. Hyperactivity of liver chi and deficiency of kidney yin are main source of headache. On the treatment, relieve of muscle tension and correction of bad habit are emphasized in western medicine while promotion of harmony among the internal organs is main target in oriental medicine.

• 제어로봇시스템학회논문지
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• 제7권3호
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• pp.238-245
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• 2001

This paper describes a method for detecting a close leading vehicle using the contour of the vehi-cles rear wheels. The contour of a leading vehicles rear wheels in 속 front road image from a B/W CCD camera mounted on the central front bumper of the vehicle, has vertical components and can be discerned clearly in contrast to the road surface. After extracting positive edges and negative edges using the Sobel op-erator in the raw image, every point that can be recognized as a feature of the contour of the leading vehicle wheel is determined. This process can detect the presence of a close leading vehicle, and it is also possible to calculate the distance to the leading vehicle and the lateral deviation angle. This method might be useful for developing and LSA (Low Speed Automation) system that can relieve drivers stress in the stop-and-go traffic conditions encoun-tered on urban roads.

• 전력전자학회논문지
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• 제25권5호
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• pp.343-349
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• 2020

This study proposes a new single inductor converter for DC grid systems. A conventional system is composed of two independent converters for controlling battery and load. This system is simple but it has two inductors that affect power density and efficiency. The proposed converter can reduce the number of inductors by integrating the two converters and relieve voltage stress on switches by using a battery switching cell. Accordingly, power density and efficiency can be improved using a single inductor and lower voltage-rated switches. A prototype of a 500 W converter is built, and each mode is experimented on to confirm the validity of the proposed converter.

• 한국주조공학회지
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• 제2권2호
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• pp.10-17
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• 1982

This study has been carried out to determine the change of mechanical properties and microstructures by the heattreatment to relieve the residual stresses for gray cast irons. The results have been obtained from the experiment as follows; 1) The annealing above $600^{\circ}C$ for the stress relieving of gray cast iron decrease the tensile strength and hardness 2) The decrease reates of tensile strength and hardness of gray cast iron after annealing above $600^{\circ}C$ are increased with increasing the holding time. 3) The gray cast iron containing the elements of Mn, Cr has increased the heating temperature for the decrease of tensile strength and hardness. 4) The decrease of mechanical properties by annealing are assumed that the formation of ferrite takes placed from the decomposition of eutectoid cementite in the matrix.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권8호
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• pp.4315-4328
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• 2019

The present study investigated the effects of work satisfaction on quality of life for 119 paramedics, the Korean equivalent of 911 paramedics. Data collection began in July 2017 and lasted for six months. Data was collected from 410 119 paramedics of the J province and the G metropolitan area who consented to study participation. The results showed that the higher the job satisfaction of the participants, the higher the quality of life (r = 0.508, p = 0.008). The factors affecting the quality of life were leisure activity, subjective health, and job satisfaction. For 119 paramedics to improve their quality of life, they need to relieve work stress and fatigue through leisure activities, and recover and maintain their health through sufficient rest. Moreover, returning to work in a healthy state likely leads to increased job satisfaction, and the quality of life will increase accordingly. Therefore, 119 paramedics should be permitted to have plenty of leisure time outside their work hours and should be able to maintain health through periodic health checks.

• International Journal of Internet, Broadcasting and Communication
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• 제16권3호
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• pp.139-145
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• 2024

In modern society, many adults seek emotional solace by reconnecting with their childhood memories through "kidult" culture, especially as single-person households increase. This trend spans fashion, collectibles, movies, animations, games, and character merchandise, with Hollywood playing a significant role in its growth during the 1980s and 1990s. Kidult culture allows adults to relieve stress, foster creativity, and strengthen social connections, enhancing their quality of life. As this culture gains mainstream acceptance, companies are producing diverse products featuring beloved characters, appealing to a wide age range. The rise in single-person households has amplified the importance of personal expression and individuality, driving the popularity of kidult culture. Companies are leveraging this trend to create innovative designs that resonate with consumer preferences. This cultural expansion promotes new design forms and aesthetics, reflecting the evolving relationship between design and consumption. Kidult culture's growth underscores its significance in contemporary consumer and design culture, offering valuable insights into modern societal trends.