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.

광촉매를 이용한 셀룰로오스섬유의 기능화에 관한 연구 : 항균·소취성 및 자외선 차폐성을 중심으로 Focusing on Antibacterial activity, Deodorization & UV cut ability

권오경,문제기,손부헌,최영희 한국의류산업학회 2003 한국의류산업학회지 Vol.5 No.4

In this study, we measured the antibacterial activities, deodorization, UV cut ability, whiteness and SEM, according to the size(5 μm, 15 ?m) of ThiO₂, concentration(3%, 5%, 10%) and dipping temperature(50℃, 70℃) with using anatase type of TiO₂ photocatalyst. Photocatalyst is the substance which carries out functions, such as decomposition, removal, deodorization, antibacterial, etc. of a contaminant, in a place with light based on an oxidation-reduction reaction. The results of this study were as follow. Antibacterial activities are increased with increasing of the TiO₂'s concentration, and TiO₂ has high antibacterial activities for Staphylococcus aureus but it has low antibacterial activities for Klebsiella pneumoniae. The deodorization and UV cut ability is very good, therefore be able to get good effects with usingonly 3% of TiO₂. Every effects are increased by using small size of TiO₂ and high dipping temperature.

中等學校 科學敎育의 實態에 관한 調査 硏究

權寧駿,成辰慶 공주대학교 사범대학 과학교육연구소 1992 과학교육연구 Vol.23 No.1

The purpose of this study is to provide the science teachers with fundamental sources to ameliorate the condition of science education. This study was carried out by a following process-to approach and identify the problems of science education-the statistical comparison and analysis of the materials from the surveying questions concerning the current issues which the science teachers of secondary school have been suffering. Teh issues are surveyed by the classified questions as below: of curriculum, especially experimentation, educational environment, students and teachers. Under the targets of the random sampling investigation was 430 secondary schools, which were located in the direct control city of Taejon, Chungchong nam-do and Chungchong puk-do. Simultaneouely posted on the 16-th day of september, 1991, 319 of the inquiry papers, which were sent back thanksfully. The rate of the replies amount to 74.2 percentage. The remarked materials were compared and analyzed with those of 1974 and 1983. All of the data as below are described by means of the numerical value of percentage and average. The out-put results are represented as below: 1. Until recently, science curricular goals are illustrated to be so desirable, while little difference was made in the contents of science education between the two decaded. The learning methods of students have been greatly altered from the learning by testing to the learning by discovery. Nevertheless the teaching methods of teachers have been clung to the cramming system of education so far. Moreover, school hours in a week are explained to be quite less than demanded. What is needed, most of all, is to fabricate the contents of curriculum, to add school hours in a week, to give priority to the environment education and the environment science, and to expand the special intelligence education in the field of science education. 2. In the science curriculum, the heterogeneous groups are managed through the massed learning and the aspects of experimentation are transfered to the group experiment. On the other hand, the system of learning by inquiry is not well-operated as usual. Hence, it is so much requested theat we should reform the entrance examination system and normalize the science curriculum. 3. Education facilitaies are, if anything, poorly-equipped. It is needless to say that eductional enviorment should be well-equipped with comfortable classroom, school, and convenient condition for experimentation. 4. There is a tendency that most of the students think a science subject as one of the most difficult. Almost students hopes their classes will be carried out by experimentation. Accordingly, the contents of science education should be understandably trans-figured for students to be attracted. 5. The school career of science teacher truned out to be growing higher. Although having more chances to join the research study courses, many of the teachers think they have fewer than hope. Many of them are not satisfied with their teaching professions. Burdensome tasks are of course ascribed to their discontent. Consequently, the problems how we can help the science teachers to uphold the professional faculty, necessary to the practical teaching activities and the accomodation of future society, should be settled as below; to establish the advanced research study cources, to decrease the burdensome tasks of science teachers, and to build up the society so that the teachers may be cordially respected, and to accomplish the institutionalized system so that the teachers may receive everyone`s hospitality.

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".

소아 조갑진균증에서 Itraconazole 주기요법의 치료효과

권경술,이재봉,진현우,오창근,장호선,임재영 대한의진균학회 2003 대한의진균학회지 Vol.8 No.4

말초혈액에서 Tg mRNA에 대한 역전사 중합효소 연쇄 반응법의 갑상선 재발암의 분자생물학적 진단

권성일,박기룡,김현영,신채희,임영찬,최영식,박요한,이강대,장희경,이재화,염하용 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.4

연구배경: 갑상선암은 다른 조직에 발생한 암에 비해 비교적 천천히 자라므로 대부분 예후가 양호하지만, 일부에서는 주위 조직으로 침윤하거나 혹은 원격 전이로 인하여 치명적인 결과를 초래할 수 있다. 갑상선전절제술 및 131^I 제거술 후 경과 관찰시 갑상선암의 재발과 전이의 진단에 있어 131^I 스캔과 혈청 Tg의 측정이 현재 임상에서 가장 많이 이용되고 있으나 이 방법에는 여러 가지의 결점이 있다. 최근 Tg mRNA에 대한 RT-PCR법을 이용한 여러 연구결과는 131^I 스캔과 혈청 Tg 측정의 결점을 보완할 수 있는 좋은 보조적인 진단법으로 이용할 수 있을 가능성을 제시하였다. 이에 말초혈액에서 측정한 Tg mRNA에 대한 RT-PCR법이 갑상선 절제술 및 방사성요드 치료 후 갑상선암의 재발 및 전이 유무의 진단에 유용한가를 알아보고자 이 연구 시행하였다. 방법: 분화된 갑상선암으로 진단된 후 갑상선전절제술을 시행받고 방사성요드 치료를 받은 환자 중 현재까지 한차례에 이상 추적 방사성요드 전신 스캔을 시행하고 추적관찰이 가능했던 유두선암 35예, 여포선암 5예를 대상으로 연구를 시행하였다. 대상군은 131^I 스캔 소견상 음성인 군(Group Ⅰ), 잔여조직이 있는 군(Group Ⅱ), 국소전이가 있는 군(Group Ⅲ), 및 원격전이 군(Group Ⅳ)으로 구분하였다. 정상 대조군은 갑상선질환이 없는 10예의 건강인으로 하였다. 대상환자의 말초혈액을 이용한 Tg mRNA에 대해 특이적인 primer를 이용하여 RT-PCR 및 nested RT-PCR을 시행하였다. 결과: 본 연구 결과는 다음과 같다. 1) 131^I 스캔 소견상 음성인 군 21예 중 1예에서 Tg가 양성소견을 보였다. Anti Tg Ab가 양성인 4예 모두 Tg가 음성을 보였다. 잔여조직이 있거나 국소전이 및 원격전이를 보인 군 19예 중 Tg가 양성인 경우는 4예였으나, Tg mRNA는 전예에서 양성이었다. 2) 131^I 스캔에서 국소 및 원격전이 소견을 보인 8예 중 4예에서 Tg가 음성으로 131^I 스캔과 혈청 Tg 사이에 불일치 소견을 보였다. 3) 말초혈액에서 특이적인 primer를 이용하여 RT-PCR 및 nested RT-PCR을 시행한 결과 대상군 40예 및 정상 대조군 10예 모두에서 Tg mRNA가 양성을 보였다. 결론: 본 연구에서 갑상선 절제술 및 방사성요드 치료 후 갑상선암의 재발 및 전이 유무를 평가함에 있어 역전사 중합효소 연쇄 반응법을 이용한 Tg mRNA 측정의 의의는 재평가되어야 한다고 생각된다. Background: Differentiated thyroid cancer is the most common endocrine malignancy. Despite advances in the treatment of thyroid cancer, disease recurrence and metastasis may occur in as many as 20% of patients, and so continues to pose major problems in its clinical management. Serum thyroglobulin (Tg) measurements, by immunoassay, are used to detect residual or recurrent thyroid cancer following thyriod ablation. However, the usefulness of immunoassay is limited by both the requirement for thyroid hormone withdrawal, to attain optimal test sensitivity, and interference by the antithyroglobulin antibody (Anti-Tg Ab). Recent studies have reported the clinical usefulness of reverse transcription-polymerase chain reaction (RT-PCR) detection of Tg mRNA in the peripheral blood of patients with differentiated thyroid carcinomas. We performed this study to evaluated the usefulness RT-PCR of Tg mRNA in peripheral blood of patients with thyroid carcinoma following a total thyroidectomy and radioiodine ablation therapy. Methods: Forty cases that underwent a total thyroidectomy and radioiodine ablation therapy were included in this study. Of the 40 patients, 35 were papillary carcinomas and 5 were follicular carcinomas. Ten normal control subjects were also studied. Tg mRNA was extracted. Then RT-PCR and nested RT-PCR, were run with specific Tg primers. Concurrently, DNA sequencing of the isolates was carried out to prove the isolates were identical to the nucleotide sequence of the Tg. Results: The Tg was detected in 4 of 19 patients, with either a residual thyroid bed, or metastasis, on a 131^I whole body scan and in 1 of 21 patients with a negative radioiodine scan. Surprisingly, the Tg mRNA was detected in all the patients and normal controls. Conclusion: From our results we can not recommend Tg mRNA, detected by RT-PCR in peripheral blood, as a tumor marker superior to that of the Tg serum level. We consider an intensive re-evaluation of the method is required before considering its clinical applications (J Kor Soc Endocrinol 17:501∼513, 2002).

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.

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.

수술실 간호사의 간호업무 분석

권성복,조경숙,박영숙,김동옥,이여진,이은희 대한간호행정학회 2008 간호행정학회지 Vol.14 No.1

Purpose: The purpose of this study was to identify nurses' duties and tasks for job analysis of the nurses in the operating room. Methods: This study was descriptive investigation research using the 3-point likert scale questionnaires and the level of importance, difficulty and the frequency of each duty and task were analyzed. Data were collected by 422 OR nurses from 57 hospitals. Results: Job of OR nurses included 13 duties and 105 tasks. The 13 duties were ‘management of operative patient’, ‘assistive work for operation’, ‘supportive work for operation’, ‘infection control in OR’, ‘management of equipments and instruments for operation’, ‘administrating medicine for operation’, ‘supplies management for operation’, ‘safety management for operation’, ‘environmental management for operating room’, ‘administrative work for operation’, ‘education for operating room personnel’, ‘development of operation procedure books’ and ‘self development of OR personnel’. Conclusion: This study identified duties and tasks performed by OR nurses. Based on these results, the importance, frequency, and difficulty in this study will provide research evidence for developing training programs for OR nurses.