• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.53-62
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• 2002

Condition monitoring plays a vital role since it sustains reliable operation of industrial plants and machinery in the pursuit of economic whole life operation. In order to achieve this goal, it is needed to monitor various parameters of mechanical system such as vibration, wear, temperature and etc., and finally to diagnosis the root causes of any possible abnormal machine condition. In this work, a machine failure caused by mechanical looseness was experimentally simulated and on-line measurement of the vibration, wear and temperature were simultaneously measured. For the quantitative analyses of machine wear, several statistical parameters of the wear particle size distribution were obtained through the center moment method of the Weibull distribution function, and they were compared to vibrational characteristics. Results showed that the wear and vibrational characteristics did not reveal a strong correlation each other in a loosely supported proceeding bearing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.527-532
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• 2014

Generator is the main equipment of a power plant that generates electric power. The line frequency is 60Hz, since that is operated at 3600rpm in fossil power plant. Therefore, the specific frequency 120Hz by the electromagnetic excitation force is generated inherently. If the looseness of stator at generator happens, abnormal sound that has 120Hz and the harmonic frequency is emitted from generator frame. In that case, binding of end-winding or re-wedging is needed for the reduction of sound level. In case of severe level of sound, belly band can be additionally installed at core. In this paper, the characteristics of generator sound is described and modal data is analyzed after installation of belly band.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.387-392
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• 2019

A technique was researched to detect bolt looseness using a transfer impedance technique (the dual piezoelectric material technique) for monitoring the structural health of a bolt joint. In order to use the single piezoelectric material technique, an expensive impedance analyzer should be used. However, in the transfer impedance technique, low-cost fault detection can be performed using a general function generator and a digital multimeter. A steel plate frame test specimen composed of bolt joints was fabricated, and the tightening torques of the bolts were loosened step by step. By using the transfer impedance method, the damage index was obtained. It was found that the presence of faults could be reasonably estimated using the damage index, which increased with the degree of bolt looseness. An experiment was performed on the same specimen using the single piezoelectric material technique, and the results showed a similar tendency. It could be possible to estimate the damage of a bolt joint at low cost by eliminating the expensive impedance analyzer. This method could be used effectively for structural health monitoring after carrying out a study to estimate the fault location and severity.

• Korean Journal of Human Ecology
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• v.21 no.3
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• pp.567-576
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• 2012

The purpose of this study was to analyze and determine the relationship between physiological responses including blood flow rate and garment pressure, and the feeling of restrictive tightness associated with the wearing skinny pants as a popular clothing style. Evaluation was based on material type, posture and activity type, and body part location. Five female college students took part in this research. Five kinds of experimental clothes with waist measurements of 66cm were chosen. An analysis of the selected skinny pants demonstrated the degree of the whole looseness was higher in this order: clothing type A>B>D>C, and E with E being knitted cloth. Garment pressure was the highest in the front knee portions and was lowest in the outside thigh region. Garment pressure was highest in this sequence : clothing type C>=D>A>=B>E. In terms of posture and activity types, garment pressure was the highest when research participants were crouching, and was the lowest when standing. The blood flow rate was highest in this order: clothing type E>D>B>A>C. Type C skinny pants impeded blood flow and demonstrated the tightest and most restrictive relationship. Blood flow rate varied depending on the type of movement and was highest in this order: getting up, rowing, kicking, jumping and O-shaped leg posture. The results of subjective pressure evaluation demonstrated that pressure was highest in this order: E>=C>B>A>D. These results suggests the need to improve on the patterns and the material design in the area of the front knees. The degree of the looseness when wearing skinny pants did not always correspond to garment pressure or subjective sensation.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.3
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• pp.150-159
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• 2012

Objective : The purpose of this study was to evaluate the effect of korean herbal cosmetics for facial skin elasticity. Methods : We recruited patients and divided them to cosmetics group and control group randomly. We provided korean herbal cosmetics to cosmetics group and subjects in cosmetics group applied the provided cosmetics for 4 weeks. Control group waited and applied cosmetics that had previously used for 4 weeks. We assessed all subjects in 0 week, 2 weeks and 4 weeks. Primary assessment instrument was moire topography photo scale. Second assessment instrument was skin moisture, oiliness and elasticity which assessed with skintouch system v1.0, detox/regeneration questionnaire score and self-evaluating facial wrinkle/looseness score. Result : Moire topography photo scale improved in cosmetics group than control group significantly. Skin moisture and elasticity assessed with skintouch system improved in cosmetics group than control group significantly while skin oiliness assessed with skintouch system have not improved significantly. Detox/regeneration questionnaire score and self-evaluating facial wrinkle/looseness score improved in cosmetics group than control group significantly. Conclusion : Korean herbal cosmetics application might be effective method for facial skin elasticity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.2
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• pp.167-172
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• 2013

In order to establish the diagnostic indices of skin diseases, some physiological and pathological concepts of interstices(腠理) were researched based on , and western dermatology with etymological analysis. As physiological indices for diagnosis of skin diseases, measurement of epidermis and dermis using ultrasonogram in the zhongwan and dachui's location. And for grading looseness and fineness of interstices with 3 unsound groups, measuring numbers and sizes of sweat pores in each point's 1 cm diameter circular area using comparative method and palpation assessment. Another index is superficial temperature. As pathological indices for diagnosis, validating volumes of dead skin cells and grading degrees of atrophy and degeneration of skin lesion. And as supplementary measures, absorptive degrees of cosmetics on face should be recorded according to 3 grades. These diagnostic indices can contribute to establishment of standard pattern identification and prescription of skin diseases through converting anatomical cognizance into classical concepts of interstices objectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.2
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• pp.302-313
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• 1997

The purpose of this study was to investigate the meaning structure of Korean costume image in contemporary Korean fashion design expressed beauty of traditional dress. This study compared Korean and American regarding the evaluation of Korean costume image. The result was as follows; 1. The constructing factors of Korean costume image were found out as elegance, simplicity, neatness, femineity, looseness. (total variance; 62%) 2. The visual evaluation between Korean and American were sinificantly different regarding 5 factors. 3. Korean costume design were classified 4 clusters. Korean traditional fabrics and colors were commonly used in the 4 clusters. Difference of design were found in the structure of form. Formation of Korean costume image were influenced by silhouette and pattern of fabric. 4. Image of 'Would like to purchase' were influenced by image of taste.

• Smart Structures and Systems
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• v.6 no.4
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• pp.389-403
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• 2010

By using image recognition technology, this paper presents a new fault diagnosis method for rotating machinery with artificial immune algorithm. This method focuses on the vibration state parameter image. The main contribution of this paper is as follows: firstly, 3-D spectrum is created with raw vibrating signals. Secondly, feature information in the state parameter image of rotating machinery is extracted by using Wavelet Packet transformation. Finally, artificial immune algorithm is adopted to diagnose rotating machinery fault. On the modeling of 600MW turbine experimental bench, rotor's normal rate, fault of unbalance, misalignment and bearing pedestal looseness are being examined. It's demonstrated from the diagnosis example of rotating machinery that the proposed method can improve the accuracy rate and diagnosis system robust quality effectively.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.198-199
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• 2009

산업이 발달함에 따라 전기는 우리 일상 생활에 있어 없어서는 안 될 중요한 요소이나 그 사용에 따른 화재 위험성 또한 날로 증가하는 추세이다. 특히 전기 화재의 경우 전기용품 사용에 있어 그 사고를 미리 감지하기 어려워 사고 위험성에 대하여 무방비 상태가 된다. 특히 우리나라의 경우 전체 화재 건수 중 전기 화재가 차지하는 비율은 30%이상으로 일본, 미국 등 선진국에 비해 높아 화재 원으로서 전기 화재 예방에 대한 그 중요성 대두된다 본 논문에서는 전기화재 발화 원인 중 단자대 접촉부 접촉 불량으로 야기된 과열에 의한 화재를 예방하기 위하여 접촉부 접촉 저항을 검출 하는 시스템에 대하여 알고리즘 개발 및 설계 하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.2
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• pp.209-214
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• 1999

Chronic recurrent TMJ dislocation results in difficulty of mastication, speaking, and swallowing due to the limitation of the mandibular movement. Etiologic factors are considered as the looseness of the capsule and ligaments, the decrease of the articular eminence, condylar morphologic change, muscular disharmony near by TMJ, and the decrease of the vertical length of the mandibular ramus. Treatment approach has been suggested that surgical methods are selected for the correction of the etiologic factors when conservative treatments are not effective. Many surgical methods have been reported such as eminectomy, eminence augmentation, condylotomy, and zygomatic arch down fracture technique. We performed the eminence augmentation through interpositional bone graft in chronic recurrent TMJ dislocation. This method leads to favorable postoperative result without recurrence and complication, so we report the case with related references.