• 소음진동
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• 제9권3호
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• pp.613-620
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• 1999

디스크 두께 변화(DTV)에 의해 야기되는 져더현상은 일반적으로 차체진동, 브레이크 페달 떨림, 그리고 스티어링 휠의 떨림에 의해 감지된다. 이번 연구에서는, 차수분석 및 Operational Vibration Analysis(OVA)를 통해 차체진동이 DTV profile에 의해 어떻게 영향을 받는지를 중점적으로 조사하였다. 진동 측정위치는 knuckle, lower arm, lower arm 연결 차체부위이고, 져더 발생 DTV profile도 실측하였다. 시험 분석 결과, DTV는 져더현상에 차수별 상대적인 방향 기여도를 나타내며 특히 디스크 회전 2차 성분은 차량진행 방향으로의 lower arm 진동을 현저하게 야기시키는 것으로 나타났다. 이러한 시험 및 분석 기술은 져더 현상을 진단하고 문제를 개선하는데 유효하리라고 예측된다.

• PNF and Movement
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• 제20권2호
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• pp.253-262
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• 2022

Purpose: The aim of this study was to identify the effects of performing the half squat exercise with Kinesio taping (HSEKT) on trunk and lower extremity muscle activity and balance ability in general university students. Methods: The 32 participants were randomly assigned to either the HSEKT group (half squats with Kinesio taping) or the control group (half squats with sham Kinesio taping). Both groups performed half squats with either Kinesio taping (HSEKT group) or sham Kinesio taping (control group) for 30 min/day, 3 times/week for 6 weeks. The Noraxon mini direct transmission system (DTS) electromyography (EMG) system was used to evaluate trunk and lower extremity muscle activity. BioRescue equipment was used to measure the movement area of the center of pressure with eyes open and eyes closed. The muscle activity of the trunk and lower extremities and the balance ability of all participants were measured before and after the intervention. An independent t-test was used to statistically analyze the pre- and post-intervention EMG and balance ability results. Results: The trunk and lower extremity muscle activity was found to have significantly improved in the HSEKT group and the control group after the intervention (p < 0.05). Also, the balance ability of the HSEKT group differed significantly after 6 weeks of training compared to that of the control group (p < 0.05). Conclusion: The findings of this study show that performing half squats with Kinesio taping had a positive effect on trunk and lower extremity muscle activity and balance ability in general university students.

• 복식문화연구
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• 제31권6호
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• pp.793-805
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• 2023

This study analyzes the body shapes of lower-body obese female adolescents and proposes a slacks pattern suitable for their body type. Lower-body obesity is a prevalent type of teenage obesity, and our proposals aim to improve consumer satisfaction in ready-to-wear clothes across this demographic. We first observe characteristics of obese lower bodies, noting significantly above-average thigh and hip circumference. These figures indicate a high degree of curvature in obese lower bodies, along with a large drop value. Leveraging this data, we develop a novel slacks pattern using 3D avatars in a virtual simulation system. The formulas for the main areas of the pattern are as follows: front waist girth W/4+0.75cm+0.5cm, back waist girth W/4+0.5cm-0.5cm, front hip girth H/4+1.25cm-0.5cm, back hip girth H/4+2cm+0.5cm, front crotch extension H/16+0.5cm, back crotch extension H/8+1cm. Results from appearance evaluations show that this pattern minimizes strain rate on the waist and hips, and its average score is significantly higher than that of an alternative pattern that was also evaluated. The minimized strain rate and high average score indicate that our pattern assigns a sufficient amount of space to the appropriate areas. Based on these results, we expect our research to inform slacks pattern development and production for obese consumers of all types.

• 한국강구조학회 논문집
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• 제14권3호
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• pp.463-470
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• 2002

TEC-BEAM System은 구조용 CT형강, PC 콘크리트 그리고 현장타설콘크리트 슬래브로 이루어진 합성보이다. 이 시스템은 단순보에 대한 휨 및 전단실험을 수행하였고 우수한 거동을 보였다. 그러나 현장적용을 위해서는 TEC-BEAM과 RC 기둥 강접합 상세개발이 필요하다. 이 접합부는 TEC-BEAM의 하부에 발생하는 힘을 기둥에 전달하기 위한 매캐니즘을 발생해야만 한다. 그래서 TEC-BEAM의 단면이 증대되어 TEC-BEAM 플랜지 하부로 철근이 배근되는 접합부를 개발하였다. 본 논문에서는 제안된 시스템의 구조적 성능 평가를 위해 2개의 실험체에 대하여 실험하였다. 실험변수는 철근의 정착길이 즉, 증대된 단면의 길이이며, 실험결과 제안된 시스템은 우수한 접합부를 구조 성능을 가지고 있음을 확인할 수 있다.

• 한방안이비인후피부과학회지
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• 제18권3호
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• pp.66-74
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• 2005

Objective: Stress is one of the most important etiological factors in our lives. Human body makes effort to keep his homeostasis from stress by using autonomic nerve system. So we need markers which can evaluate autonomic nerve system easily. HRV represents such markers. Sympathetic and Parasympathetic nerve system are part of autonomic nerve system, related with cur body and diseases in ENT, Dermatology, Ophthalmology are also deeply related with stress, Sympathetic and Parasympathetic nerve system. So we can expect that it can help understanding patients to evaluate autonomic nerve system with HRV Research Methods and Procedures: Forty one patients who have seif-recognized stress in Dept. of Oph & Otolaryngo & Dermatology were selected. SDNN. RMSSD, LF, HF, norm-LF, norm-HF, LF/HF ratio, LnLF, LnHF were checked. Results: Men showed lower SDNN, HF, and LnHF than women(p<0.05). Age over-forty group showed significant lower SDNN, LF, HF, LnLF, LnH(p<0.01), and lower RMSSD(p<0.05) than age under-forty group. There's no big differences for age at norm-LF, norm-HF, and LF/HF ratio. Skin disease group showed higher SDNN, RMSSD, LF, HF, LnLF, LNHF than the others, facial palsy group showed higher norm-HF. LF/HF ratio, and mouth-throat group showed higher norm-LF, but there's no statically significant difference. Comparing skin disease group with the others, the others showed statically significant low SDNN(P<0.01), RMSSD, LF, HF, LnLF and LnHF(P<0.05).

• 한국생활과학회지
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• 제12권4호
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• pp.559-570
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• 2003

The focus of this research was concerned with studying lower body type for Korean adult males. To understand the features of men's lower body required to organize an optimal sizing system for men's tight-fit slacks, information from the measuring values based on research on the physical standard of the nation(l997) were summarized; in addition, a factor analysis and a cluster analysis among multivariate analyses were performed. In terms of the need for appropriate fit in motorcycle wear, basic lower body parts applying to each item had to be taken into consideration to enhance sizing suitability. In the case of the length of the lower limbs, the inclusion of protectors plays an important role in affecting sizing. The factors related to the lower body were defined as follows: Factor 1 was the vertical dimension of the lower body, Factor 2 was the horizontal dimension of waist and hip, Factor 3 was the horizontal dimension of the lower limbs, Factor 4 was the length of hips, and Factor 5 was the ankle height. The lower body part was also divided into 3 clusters. Cluster 1 referred to the smallest stature and skeleton structure among the 3 body types. Cluster 2 represented the biggest stature, with a thin lower limbs body type. Cluster 3 represented a medium stature but with a large skeleton structure of lower limbs, a muscular type. In conclusion, Cluster 2 appeared most in the 20s age groups, but Cluster 3 appeared most in each of the 30s, 40's, and 50's age groups.

• 신재생에너지
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• 제3권4호
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• pp.31-37
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• 2007

Because of their low operating and maintaining costs, ground-source heat pump(GSHP) systems are an increasingly popular choice for providing heating, cooling and water heating to public and commercial buildings. Despite these advantages and the growing awareness, GSHP systems to residential sectors have not been adopted in Korea until recently. A feasibility study of a residential GSHP system was therefore conducted using the traditional life cycle cost(LCC) analysis within the current electricity price framework and potential scenarios of that framework. As a result, when the current residential electricity costs for running the GSHP system are applied, the GSHP system has weak competitiveness to conventional HV AC systems considered. However, when the operating costs are calculated in the modified price frameworks of electricity, the residential GSHP system has the lower LCC than the existing cooling and heating equipments. The calculation results also show that the residential GSHP system has lower annual prime energy consumption and total pollutant emissions than the alternative HVAC systems considered in this work.

• 소성∙가공
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• 제19권8호
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• pp.447-451
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• 2010

In this paper, a useful die system for warm plate forging of a large axle housing of heavy-duty trucks is presented. A die system composed of material flow guide pin as well as upper die and lower die is proposed to reduce the inherent thickness reduction along the bent corner of the product which deteriorates structural strength and fatigue life in its service. The role of the pin assembled in the upper die is to prevent formation of sharp corner in early forming stage and to supply material in the lower die cavity sufficient enough to thicken the bent corner at the final stroke. The mechanism of the die system is given and its effect on corner thickness of the product is revealed by two-dimensional finite element analysis under plain strain assumption. Three-dimensional finite element solutions are also given to verify validity of the two dimensional approach and to show the mechanics of the die system in detail. The die system has been successfully applied to manufacturing the axle housing of heavy-duty trucks.

• 한국정밀공학회지
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• 제31권12호
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• pp.1107-1113
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• 2014

In this article, the megasonic cleaning system for cleaning micro/nano particles from flat panel display (FPD) surfaces was developed. A piezoelectric actuator and a waveguide were designed by finite element method (FEM) analysis. The calculated peak frequency value of the quartz waveguide was 1002 kHz, which agreed well with the measured value of 1003 kHz. The average acoustic pressure of the megasonic cleaning system was 43.1 kPa, which is three times greater than that of the conventional type of 13.9 kPa. Particle removal efficiency (PRE) tests were performed, and the cleaning efficiency of the developed system was proven to be 99%. The power consumption of the developed system was 64% lower than that of the commercial system. These results show that the developed megasonic cleaning system can be an effective solution in particle removing from FPD substrate with higher energy efficiency and lower chemical and ultra pure water (UPW) consumption.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.515-518
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• 2007

Because of their low operating and maintaining costs, ground-source heat pump(GSHP) systems are an increasingly popular choice for providing heating, cooling and water heating to public and commercial buildings. Despite these ad- vantages and the growing awareness, GSHP systems to residential sectors have not been adopted in Korea until recently. A feasibility study of a residential GSHP system was therefore conducted using the traditional life cycle cost(LCC) analysis within the current electricity price framework and potential scenarios of that framework. As a result, when the current residential electricity costs for running the GSHP system are applied, the GSHP system has weak competitiveness to conven- tional HVAC systems considered. However, when the operating costs are calculated in the modified price frameworks of electricity, the residential GSHP system has the lower LCC than the existing cooling and heating equipments. The calculation results also show that the residential GSHP system has lower annual prime energy consumption and total pollutant emissions than the alternative HVAC systems considered in this work.