Mechanical Characterization of Nano-Structured Materials Using Nanoindentation

( Ju Young Kim ),( Sung Hoon Kim ),( Jung Suk Lee ),( Kyung Woo Lee ),( Dong Il Kwon ) 대한금속재료학회 ( 구 대한금속학회 ) 2006 METALS AND MATERIALS International Vol.12 No.3

The principal strengths of the nanoindentation technique, which is used extensively to measure the mechanical properties of nano/micro materials, are easy sample preparation and simple experimental method. Hardness and Young`s modulus are essential properties measured by nanoindentation; hardness corresponds to resistance to plastic deformation whereas Young`s modulus is related to elastic deformation. Two key difficulties arise in association with nanoindentation on small volumes: measurement accuracy and material response. Here we discuss the indentation size effect (ISE) considering tip bluntness and variation in hardness of nano-multilayers with a bilayer period, representative research on measurement improvement, and material response at nanoscales.

중ㆍ고년여성의 하지 근 기능과 요부 및 대퇴근 횡단면적의 상관관계

김창근,이수경,권영우,박정배 한국체육대학교 체육과학연구소 2001 국제학술대회논문집 Vol.20 No.1

The purpose of the present study was to investigate the relationship between isokinetic muscle function and muscle cross-sectional area (CSA). Twelve women participated in the present study, divided young (n=6, 23.7±1.9 year) and elderly women (n=6, 60.3±6.8 year). Isokinetic strength (power, strength, endurance) and CSA (psoas major and thigh muscles) measured with dynamometer and computerized tomograph, respectively. Cross-sectional area of psoas major muscle in elderly group revealed markedly smaller than in young group, but thigh muscle was not the case. Muscle CSA in young women correlated between power and endurance and psoas major muscle, as well as between muscle strength and CSA of thigh muscle. But no correlation occurred between strength and cross sectional area, except endurance which was highly correlated between CSA and endurance. In conclusion, aging decreases muscle function and CSA. Partially muscle strength correlated with muscle CSA in young women, but no correlation occurred in elderly women. Further study needed to elucidate the exact mechanism related to aging muscle with muscle density and neuromuscular function.

신경회로망 제어기를 이용한 PID 파라미터 추정에 관한 연구

權重東,裵銀敬,金恩基,全基英,李承桓,吳鳳煥,李勳九,金容珠,韓慶熙 明知大學校 産業技術硏究所 2006 産業技術硏究所論文集 Vol.25 No.-

In this paper, supposed to solve these problem to PID parameters controller algorithm using ANN. In the proposed algorithm, the parameters of the controller were adjusted to reduce by on-line system the error of the speed of IM. In this process, EBPA NN was constituted to an output error value of an IM and conspired an input and output. The performance of the self-tuning controller is compared with that of the PH) controller tuned by conventional method (Ziehler-Nichols). The effectiveness of the proposed control method is verified thought the Matlab Simulink and experimental results.

男子高校選手 集團의 權限構造에 關한 硏究 : 全南道內 選手를 中心으로 Laying Stress on Sport groups in Chonnam Province

權永玉,張卿洙 忠南大學校體育科學硏究所 1986 體育科學硏究誌 Vol.4 No.1

The purpose of this paper is to coarify the power structure of sport Groups with special reference to the power of determining group goals and norms and to darify the relation ship between the group Cohesiveness and team success. In order to achieve this purpose, three following patterns of power structure are clarified by examining who actually has the power of determining group goals and norms. They are “membership pattern" in which all member of a group have the equal power in determining goals and norms. “captain pattern" in which some few powerfull members momopolize the right to determine norms and goals, and “non-membership pattern" (It can also be called “outsider control pattern") in which some outcider have the determining powers, and Group Cohesiveness is examined. The subjects were the 18ma1e middle school sport groups and the male high school sport groups in chonnam province. The results obtained are as follows. 1. The power structure of sport groups . 1) Korean sport groups are determined by “non-membership pattern" (50.6%,) and “membership pattern" (30%), “Captain pattern" (19.4%) 2) Korean male middle school sport groups are determined by “non-membership pattern"(46.2%) and “ membership pattern" (35.6%) “Captain pattern" (16.7 %) 3) Korean male high school sport groups are determined by “non- membership pattern" (35.6%)and “ membership pattern" (24.4 %), “Captain pattern" (22.2 %) 4) Coacting task groups are determined by “non-membership”(45%) and “membership pattern"(35 %), “captain pattern" (20%) 5) Counteracting task groups are determined by “non-membership pattern" (46.7%) and “captain pattern" (28.3%) “membership pattern" (25 %) 6) Interacting task groups are mainly determined by “non-membership pattern" (60%) and “membership pattern" (30%) 7) The higher the teem success. the more the “ non-membership pattern”. 8) The lower the team success. the more the “ membership pattern".

체중감량이 유도선수의 Renin, 면역기능 및 유·무산소 운동능력에 미치는 영향

권영우,전승훈,김진해,민경선,민진아 한국스포츠리서치 2001 한국 스포츠 리서치 Vol.12 No.4

The purpose of this study was to investigate the effect of short terms weight reduction period on body composition and body fluid. Seven Judo athletes (21±1.21 yrs) were matched and randomly placed. Body weight reduction period consists of 7 day. Each groups reduced body weight by 3%(2th day from pre weight reduction), 5%(4th day from pre weight reduction, 7%(7th day) and investigated the recovery period on 3 hour after breakfast, lunch, and 1day, 2day after 7% body reduction. Weight reduction reduced weight during weight reduction period then returned to baseline during recovery(p<.05) and decreased LBM, electrolyte, and immune function and then increased in recovery period to baseline. In conclusion, weight reduction of Judo athletes caused the change biological variable and performance and STWR may detrimental effects body' homeostasis.

포커스 그룹을 이용만 임상간호사의 임파워먼트 경험에 관한 연구

권성복,염영희,권은경,이윤영 대한간호학회 간호행정학회 2007 간호행정학회지 Vol.13 No.4

Purpose: This study was to explore the empowerment experienced by hospital nurses. Methods: Focus group was used to gather data and open coding method suggested by Strauss and Corbin was used to analyze the data. Thirty-four nurses who have clinical experience of more than three years at three university hospitals were participated in this study. Results: Five categories were identified: Getting chances of opportunities to show personal capabilities and motivations, acknowledgement, support, recognition and delightfulness. The major sources of empowerment were the acknowledgement of patients and family, colleagues, supervisors. doctors, and other personnels in hospital. Conclusion: Focus groups could be an useful tool for empowerment research in nursing. further research will be needed to clarify the relationship among individual, group and organization.

불소화계면활성제 함유 DPPC/Cholesterol 및 DPPG/Cholesterol 베지클의 BSA(bovine serum albumin)친화성 연구

권경옥,김명자,김현영 숙명여자대학교 자연과학연구소 1998 자연과학논문집 Vol.- No.9

본 연구에서는 항원(antigen). 항체(antibody) 등을 삽입시켜 자극반응성 베지클을 제조의 예비실험으로 대표적인 생체 단백질 BSA(bovine serum albumin)와 베지클의 친화도에 관해 알아보았다. DPPC(dipalmitoylphosphatidylcholine)/Chol, DPPG(dipalmitoylphos-Phatidylglycerol)/Chol,DPPC/Chol/FFS(ammonium pentadeca-fluorooctyrate)/FS(sodium bis(1H,1H,2H,2H-heptadecafluorodecyl)-2-sulfosuccinate), DPPG/Chol/ FFS/FS의 4종의 베지클을 제조하고, 제조된 4종의 베지클에 대해 column chromatography 법에 의해 BSA와의 흡착 여부를 확인했다. 실험 결과, 각 계의 베지클 입자크기는 BSA의 흡착으로 인해 감소하는 것으로 나타났고, 감소하는 정도는 DPPC/Chol와 DPPG/Chol에서 큰 것으로 나타났다. 반면, 제조된 계의 제타전위(ξ-Potential)값에는 거의 변화가 없었다. BSA와의 결합친화력의 비교에서는 DPPC/Chol. DPPG/Chol. DPPC/Chol/FFS/FS. DPPG/Chol/FFS/FS 순으로 낮아진다는 결과를 얻었다. 이들 실험결과에 바탕하여, 위의 4종의 베지클과 BSA와의 결합친화력에 대해 베지클의 표면전하와 베지클 막의 밀집성(compactness)이 영향을 미친다는 결론을 얻었다. The purpose of this study is to prepare a functional vesicle for the possible use as a biosensor. In this work, we have performed a preliminary experiment for biosensor, Four different systems of vesicle have been prepared with the composition of DPPC(dipalmitoylphosphatidylcholine)/Chol, DPPG (dipalmitoylphos-phatidylglycerol)/Chol, DPPC/Chol/FFS(ammonium pentadecafluoro-octyrate)/FS(sodium bis(1H,1H,2H,2H-heptadecafluorodecyl)-2-sulfosuccinate) and DPPG/Chol/FFS/FS. By use of column chromatography, it was found that BSA has been adsorbed onto the vesicle structure. The size of vesicle was found to decrease as adsorption occurs between the two species and the extent was greater in the systems of DPPC/Chol and DPPG/Chol. However, the δ-potential of the system remained essentially unchanged. The affinity of vesicle to BSA was found to decrease in the order of DPPC/Chol, DPPG/Chol, DPPC/Chol/FFS/FS and DPPG/Chol/FFS/FS. Based on these findings, it may be concluded that the affinity of vesicles onto BSA was affected by the surface charge and the compactness of vesicle.

鷄龍山 陸松群落 및 리기다松群落의 林床植生에 關하여

權五溶,辛昌男,吳炅煥 충남대학교 자연과학연구소 1979 學術硏究誌 Vol.6 No.2

A study was carried out to ascertain the standing crops, species composition, and relationships between the standing crops and soil nutrients in the Pine forest and the Pitch pine forest of Gyeryong Mt. Species compositions of the Pine forest and the Pitch pine forest were 36 and 20 species, and dominant species of them was Festuca ovina . Total live standing crops of ground vegetation, 215.28-631.67g/㎡ and 188.62-446.13g/㎡, were highest in September, and net productivities were 13.02-169.95g/㎡ and 12.62-109.58g/㎡, respectively. Total live standing crops were significantly correlated with the water content and the organic matter of soil in each forest, and comparatively with the total nitrogen and the exchangeable phosphorus in the Pitch pine forest.

韓國 傳統住居環境의 風水 特性 分析

권영휴,심우경 한국정원학회 2002 한국전통조경학회지 Vol.20 No.2

This research is concerned with a proper application of Feng-Shui(風水), and Oriental concept of living harmoniously with the energy of the surroundings, to our modern envitonment. The purpose of this study is to define the concept of traditional Feng-Shui theory, to look into the characteristics of residential environments in connection with Feug-Shui, and to discern the physical and spatial features of a residential location using GIS(Geographic Information System). The forty three(43) residential cases were selected nationwide in South Korea for the study in consideration of their local envitonments. The results are summarized as follows: First, based on Hyoungse Theory(形勢論) and Yeeki Theory(理氣論), the "methodological model for Feng-Shui-based interpretation of residential location" and "methodological model for redidential surroundings" were to be developed for each theory. These models can be used as valuable data for Feng-Shui studies in the future. Second, the analysis of directions between Feng-Shui-based Jwahyang(坐向) and Jusan(主山) or Ahnsan(案山) showed that they do not match in most cases. Most of the cases of Feug-Shui-based direction in the textbooks do not match, either. Third, the distance ratio of Sashinsa(四神砂) in a residential location were being kept approximately 1 : 0.4 : 0.5 : 2 in Cheongryong(靑龍), Baekho(白虎) and Ahnsan(案山) toward the distance of Jusan(主山), 455m. The process and results of Feng-Shui-based interpretation are much worthy of application to residential site planning and landscape planning. However, it needs to be implemented continuosly.

飮食物쓰레기의 效率的 管理를 위한 物理的 特性 및 處理

권효정,정영헌,김임경,심언봉,오광중 부산대학교 환경문제연구소 2003 環境硏究報 Vol.21 No.-

This study was conducted to manage food wastes in Korea efficiently. We carried out an experiments on food wastes generated from Yeonjae gu, Pusan as a representative boundary according to the measurement of apparent density, generation quantity, physical characteristics, proximate analysis, and elemental analysis as well as drying and carbonizing, and also tested the hazardous materials in fertilizer and compost from public and private recycling center in operation. The purposes of this study are to investigate current status of food wastes recycling methods and facilities, to examine the fuelization of food wastes, and to suggest the cost effective food wastes treatment plans. Based on the results of the analysis of apparent density and water content in food wastes, it was revealed that the apparent density of food wastes was in inverse proportion to the water content. The water content of food wastes was highly influenced by the fruit and vegetables such as watermelons. These results indicate that the food wastes with about 75 ~80wt% initial moisture content should be reduced under 70wt% moisture content by drying process pier to throwing away. Comparing the heating values of the food wastes which were calculated by Dulong's equation and Steuer's equation it was revealed that Steuer's equation(HHV 5,186 kcal/kg, LHV 880 kcal/kg) was more compatible than Dulong's equation(HHV 4,676 kcal/kg, LHV 330 kcal/kg) because the results of proximate analysis for the food wastes were very similar to those of sewage sludges. Additionally, to reduce water contents of food wastes under 60wt% as acceptable water contents for fuelization, it was also found that blending with 25wt% chars made from food wastes was more efficient than the drying of food wastes itself at 105°C, 45minutes in view of completion time. Furthermore, these chars generated from food wastes (about LHV 6,608 kcal/kg) comparable to commercial charcoal(LHV 7,134 kcal/kg) generated from oak trees and lower ash contents(under 15wt% of chars) than those.