애구(艾灸)의 연소(燃燒) 구간별(區間別) 열량비(熱量比)에 대(對)한 연구(硏究)

강기원,남상수,이재동,최도영,안병철,박동석,이윤호,최용태,Kang Ki-Weon,Nam Sang-Soo,Lee Jae-Dong,Choi Do-Young,Ahn Byoung-Choul,Park Dong-Seok,Lee Yun-Ho,Choi Yong-Tae 대한침구의학회 1998 대한침구의학회지 Vol.15 No.2

In order to evaluate calorie rate of moxa-combustion(direct moxibustion=DM, indirect moxibustion with stainless steel tube=IMS, indirect moxibustion with ginger slice=IMG), calorie rate(%) in the preheating period, heating period, retaining period, and cooling period was calculated respectively to the total combustion calories in all the periods. The result are as follow: 1. Indirect moxibustion with stainless steel tube had the highest rate with the statistical significance than other groups during the preheating period, represented statistical differences between IMS group and IMG group, and also between DM group and IMS group. 2. Indirect moxibustion with ginger slice group showed the highest rate with the statistical significance and followed by DM group and IMG group during the heating period, represented statistical difference among DM, IMS, and IMG group. 3. Direct moxibustion group had the highest rate with the statistical significance than other group during the retaining period, represented statistical difference between DM group and IMG group, and also between DM group and IMS group. 4. Indirect moxibustion with stainless steel tube had the highest rate with the statistical significance than other groups during the cooling period, represented statistical differences between IMS group and IMG group, and also between IMS group and DM group.

녹용사근환약침(鹿茸四斤丸藥鍼) 및 경구투여(經口投與)가 흰쥐의 성장(成長)과 지능발달(知能發達)에 미치는 영향(影響)

강기원,고형균,이윤호,Kang, Ki-weon,Koh, Hyung-kyun,Lee, Yun-ho 대한침구의학회 2003 대한침구의학회지 Vol.20 No.6

Objective: This study was designed to investigate effects of Nokyongsageunhwan and Nokyongsageunhwan aquapuncuture on body weight, body length, intellectual development Methods: We observed body weight, body length, intellectual development after feeding Nokyongsageunhwan and Nokyongsageunhwan aquapuncuture for thirty three days, and mRNA expressions of GHRF, Somatostatin, IGF-1, NPY were analyzed by RT-PCR method. Results: The results were summarized as follows. 1. Body length was significantly increased in Nokyongsageunhwan herbal acupuncture group compared to normal group and normal saline injection group on 4th week, 2. Lower part of hind leg length was significantly increased in Nokyongsageunhwan oral administration group compared to normal group on 3rd week, and it was significantly increased in Nokyongsageunhwan herbal acupuncture group and Nokyongsageunhwan oral administration group compared to that of normal group on 4th week. 3. As results of observing memory aquisition using Morris water maze system, there was significantly difference in Nokyongsageunhwan oral administration group compared to that of normal group on 4th week. 4. As results of observing retention using Morris water maze system, staying time was significantly increased in Nokyongsageunhwan herbal acupuncture group compared to that of normal group. 5. The somatostatin mRNA expression in the hypothalamus was significantly decreased in Nokyongsageunhwan oral administration group compared to that of normal group. 6. The IGF-1 mRNA expression in the hypothalamus is significantly increased in Nokyongsageunhwan herbal acupuncture group and Nokyongsageunhwan oral administration group compared to that of normal group. 7. The NPY mRNA expression in the hypothalamus was significantly increased in Nokyongsageunhwan oral administration group compared to that of normal group, and it was increased in Nokyongsageunhwan herbal acupuncture group compared to that of normal group, but there was no significant difference. Conclusions: According to the above results, it appears that Nokyongsageunhwan oral administration and Nokyongsageunhwan herbal acupuncture on acupoint GB34 and GB39 showed effects on the growth and the intellectual development of rats.

반응표면법을 이용한 육상트랙용 고무칩층의 최적설계에 관한 연구

강기원(Kang, Ki-Weon),이승표(Lee, Seung-Pyo) 한국산학기술학회 2010 한국산학기술학회논문지 Vol.11 No.3

본 논문은 육상트랙용 복합탄성포장재의 고무칩층의 최적 배합조건을 결정하기 위하여 기계적 및 동적 성능 에 대한 각 구성요소의 영향을 평가한 것이다. 이에 소요되는 시험 횟수의 최소화를 위하여 실험계획법을 적용하였으 며 이에 따라 기계적 및 국제육상연맹(IAAF)에서 요구하는 동적성능에 대한 시험을 수행하였다. 마지막으로 반응표면 법을 이용하여 기계적 특성 및 동적 성능을 최적화하기 위한 배합조건을 결정하였다. This paper aims to evaluate the effect of each material ingredient on mechanical and dynamic performance and to determine an optimal mixing condition of a rubber granule layer. To minimize the required number of tests, the test matrix was established by using the design of experiments (DOE). The tensile tests were then performed to identify the mechanical properties. Also, to evaluate the dynamic performance that the IAAF has required for athletics tracks for athletes’ safety and balance, a series of impact tests were performed by using the so-called the “artificial athlete” machine. Finally, the response surface methodology was used to decide the optimal mixing conditions needed to achieve a high level of mechanical properties and dynamic performance.

충격손상 복합재료의 피로수명에 대한 통계적 해석 연구

강기원(Kang, Ki-Weon) 한국산학기술학회 2010 한국산학기술학회논문지 Vol.11 No.9

본 논문에서는 충격손상 복합재료의 피로수명 저하 특성과 이의 변동성을 통계적으로 분석하였다. 충격손상 복합재료의 잔류강도는 2모수 Weibull 분포에 잘 적합되었으며 충격에너지의 증가에 따라 잔류강도의 변동성은 감소 하였다. 복합재료의 피로수명은 충격손상에 의하여 크게 저하되었으며 또한 이의 피로수명에 대한 충격손상의 영향은 작용 응력진폭에 따라 변화함을 알 수 있었다. 또한 2모수 Weibull 분포를 이용하여 충격손상 복합재료의 피로수명의 변동성을 추정하였으며 충격에너지의 증강 및 응력진폭의 감소에 따라 피로수명의 변동성은 점차 감소하였다. This paper presents the probabilistic analysis for fatigue life of Glass/Epoxy laminates with impact-induced damage. For this, a series of impact tests were perfomed on the Glass/Epoxy laminates using instrumented impact testing machine. Then, tensile and fatigue tests carried out so as to generate post-impact residual strength and fatigue life. Two Parameter Weibull distribution was used to fit the residual strength and fatigue life data of Glass/Epoxy composite laminates. The residual strength was affected by impact energy and their variance decreased with increasing of impact energy. The fatigue life of impacted laminates was greatly reduced by impact energy and this trend depended on applied stress amplitude. Additionally, the variation of fatigue life was gradually decreased with the applied stress amplitude.

장기 운영 항공기 주익 구조물의 응력스펙트럼 및 피로수명 추정에 관한 연구

강기원(Ki-Weon Kang),고승기(Seung-Ki Koh),최동수(Dong-Soo Choi),심기중(Ki-Joung Shim) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11

Aged Aircraft has the several cracks due to the long-term service and these cracks deteriorate the safety and the rate of operation. To solve this, the crack propagation analysis for flight critical location is of utmost required. maneuver. It is, however, almost impossible to obtain the stress spectrum, which is crucial for the crack propagation analysis, at the FCLs of aged aircraft wing structure. In this study, to analyze the fatigue crack propagation behavior at FCL in aged aircraft, firstly the finite element analysis is performed for the 3D geometry model of wing assembly, which is obtained using CATIA from the paper drawings. And then, transfer function and stress-spectrum at FCL are derived from based on the limited load factor data and the FEA results. Finally, crack propagation rates at the FCL are analyzed using the commercial code, NASGRO.

브레이징 접합부의 고장원인 및 강도 특성 평가

강기원(Ki-Weon Kang),이병재(Byung-Jei Lee),장경영(Kyung-Young Jang),김정규(Jung-Kyu Kim) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.5

In order to understand failure cause and stress analysis, strength evaluation of joints and non-destructive test were done for brazing joint of copper pipe in household air conditioner. Strength of brazing joint was evaluated by shear test and test specimens were used by standard single lap form and actual form of brazing joint in copper pipe. In order to evaluate the effect where the temperature has an influenced on the joint during this brazing joint processing, micro vickers hardness is measured. Also, three dimensional X-ray non-destructive test was used to know defect existence of brazing joint. Internal pressure breaking tester was designed and was performed to make higher oil pressure by specific ratio within the interval of time.

학교체육시설물-철봉의 강도규정 및 이의 평가방법 개발에 관한 연구

강기원 ( Ki Weon Kang ),안병화 ( Byoung Hwa Ahn ),유승원 ( Sueng Won You ),도영민 ( Young Min Do ) 한국스포츠정책과학원(구 한국스포츠개발원) 2003 체육과학연구 Vol.14 No.1

학교체육시설물의 안전성 및 효율성을 향상시키기 위해서는 이의 구체적인 요건을 정하는 표준규격의 제정이 요구된다. 이러한 표준 규격은 품질규정, 형상규정 및 강도규정 등으로 세분화될 수 있으며 이 중 표준 규격의 핵심요소인 강도규정은 학교체육시설물이 보유하여야 하는 기준강도에 대한 내용을 포함하므로 이의 적합한 설정은 매우 중요하다. 또한 이와 같이 설정된 강도규정의 타당성 및 적합성을 검증하기 위해서는 강도규정에 대한 시험방법의 선정 역시 매우 중요하다. 그러나 철봉으로 대표되는 학교체육시설물은 대부분 운동장과 같은 야외에 설치·운영되고 또한 이의 운동형태가 매우 다양하므로 기존의 시험방법으로는 이에 대한 시험평가가 매우 어려운 실정이다. 따라서 본 논문에서는 대표적인 학교체육시설물인 야외용 철봉의 강도규정 및 이의 평가를 위한 시험방법을 제정하고 이들의 적합성 및 타당성 검증에 대한 연구를 수행하였다. The present study is aiming at developing the strength specification and evaluation methodology in horizontal bars intended for permanent installation for use at elementary, middle and high schools. For these purpose, the strength specification is, firstly, established through the structural analysis considering the environmental, service and loading conditions of horizontal bars. Additionally, an evaluation methodology is developed to identify the usefulness and conformity of the strength specification. And then this study ends with the tests for prototype of horizontal bars according to the strength specification and evaluation methodology through a portable universal testing machine, which is designed to be able to adjust the loading direction and operate outdoors.

동적응답의 변화를 고려한 점용접부의 진동피로해석

강기원(Ki-Weon Kang),장일주(Il-Joo Chang),김정규(Jung-Kyu Kim) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.4

점용접은 자동차 산업에서 차체 구조물의 대표적 접합방법으로서 차량에 피로하중이 작용할 경우 구조물 전체의 파손 발생이전에 점용접부 일부에 조기 피로파손의 발생가능성이 존재한다. 이러한 점용접부의 국부적 파손은 차량 구조물의 동적 반응 및 이에 따른 피로거동의 변화를 야기할 가능성이 존재한다. 따라서 차량과 같이 랜덤 피로하중을 받는 구조물의 피로수명 평가를 위해서는 이러한 점용접부의 국부적 파손에 의한 동적 반응의 변화를 고려하여야 한다. 본 논문에서는 점용접부의 누적피로손상으로 인한 동적반응의 변화를 고려한 진동피로해석을 수행하였다. 이에 필요한 S-N 선도는 전단 점용접 시험편에 대한 일정진폭 피로시험을 통하여 획득하였다. 또한 랜덤 피로하중하의 점용접부의 피로수명은 유한요소해석에 기반한 진동피로해석을 통하여 평가히였다. The spot welding is the primary method of joining sheet metals for body a in the automotive industry. And as the fatigue loading are applied to automobile, the some spot welds may be fractured before the whole system has failed. This local fracture of spot welds may lead to change of the dynamic response and subsequent the fatigue behavior of automobile. Therefore, the change of dynamic response caused by local fracture of spot welds should be taken into consideration to assess the fatigue life of structures subjected to random loading such as automobile. The paper deals with vibration fatigue analysis considering change of dynamic response during accumulated damage for spot welded parts. Fatigue test were carried out on tensile - shear spot - welded specimens under constant loading. And the fatigue life of spot welds under random loading was predicted using vibration fatigue analysis with finite element analysis.

동적응답의 변화를 고려한 점용접부의 진동피로해석

강기원(Ki-Weon Kang),장일주(Il-Joo Chang),김정규(Jung-Kyu Kim) 대한기계학회 2010 大韓機械學會論文集A Vol.34 No.9

점용접은 자동차 산업에서 차체 구조물의 대표적 접합방법으로서 차량에 피로하중이 작용할 경우 구조물 전체의 파손 발생이전에 점용접부 일부에 조기 피로파손의 발생가능성이 존재한다. 이러한 점용접부의 국부적 파손은 차량 구조물의 동적 반응 및 이에 따른 피로거동의 변화를 야기할 가능성이 존재한다. 따라서 차량과 같이 스펙트럼하중을 받는 구조물의 피로수명 평가를 위해서는 이러한 점용접부의 국부적 파손에 의한 동적 반응의 변화를 고려하여야 한다. 본 논문에서는 점용접부의 누적피로손상으로 인한 동적반응의 변화를 고려한 진동피로해석을 수행하였다. 이에 필요한 S-N 선도는 전단 점용접 시험편에 대한 일정진폭 피로시험을 통하여 획득하였다. 또한 스펙트럼하중하의 점용접부의 피로수명은 유한요소해석에 기반한 진동피로해석을 통하여 평가하였다. Spot welding is the primary method of joining sheet metals in the automotive industry. As automobiles are subjected to fatigue loading, some spot welds may fracture before the whole system has failed. This local fracture of spot welds may lead to change in the dynamic response and consequently affect fatigue behavior of an automobile. Therefore, this change in dynamic response should be taken into consideration to assess the fatigue life of structures subjected to spectrum loading, such as automobiles. In this study, vibration fatigue analysis was performed by taking into consideration the change in the dynamic response due to accumulated damage at spot-welded parts. Fatigue tests were carried out on tensile-shear spot-welded specimens under constant amplitude loading condition. And the fatigue life of spot welds under spectrum loading was predicted using vibration fatigue analysis method based on finite element analysis.

소형풍력발전 블레이드용 복합재료의 피로수명 분포에 대한 확률론적 평가

강기원(Ki Weon Kang) 대한기계학회 2011 大韓機械學會論文集A Vol.35 No.10

본 논문에서는 소형풍력발전시스템 블레이드 제작에 사용되는 복합재료의 피로수명 데이터에 대한 통계적 해석을 위하여 다양한 확률분포 모델의 적합성에 대한 연구를 수행하였다. 이를 위하여 삼축 유리섬유강화 복합재료를 대상으로 0°, 45° 및 90° 의 하중방향에 대한 인장시험을 실시하였다. 또한 상기의 하중방향에 대하여 4 수준의 피로응력준에서의 피로시험을 수행하였다. 이를 통하여 획득한 피로수명 데이터를 대상으로 1) 전체 적합성, 2) 끝단 적합성 및 3) 피로물리 일치성의 기준을 이용하여 2 모수 Weibull, 3 모수 Weibull, 정규 및 대수정규분포의 적합성을 평가하였다. 또한 피로수명의 분산에 대한 하중방향 및 피로응력의 영향 역시 검토하였다. This paper deals with several statistical distribution functions for the analysis of fatigue life data of composite laminates for small wind-turbine blades. A series of tensile tests was performed on triaxial glass/epoxy laminates for loading directions of 0°, 45°, and 90°. Then, fatigue tests were carried out to determine the fatigue life at the aforementioned loading directions and the fatigue stresses at four levels. Two-parameter Weibull, three-parameter Weibull, normal, and log-normal distributions were used to fit the fatigue life data of the triaxial composite laminates. The three-parameter Weibull distribution most accurately described the fatigue life data measured experimentally for all the cases considered. Furthermore, the variation of fatigue life was simultaneously affected by the loading direction and fatigue stress level.