EFFECT OF RESTORATION TYPE ON THE STRESS DISTRIBUTION OF ENDODONTICALLY TREATED MAXILLARY PREMOLARS : THREE-DIMENSIONAL FINITE ELEMENT STUDY

정현숙,김현철,허복,김광훈,손권,박정길 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.1

본 연구의 목적은 다양한 교합하중 조건하에서 아말감, 복합레진, 세라믹 인레이, 그리고 금 인레이로 수복한 근관 치료된 상악 제2소구치의 응력분포를 3차원 유한요소법으로 분석하는 것이다. 발치된 상악 제2소구치를 이용하여 근관 치료된 3차원 유한요소모형을 제작하였다. 제작된 소구치 모형의 근관와동을 위 4가지 재료로 각각 수복한 후, 협측교두 (Load-1) 또는 설측교두 (Load-2)에 500 N의 하중을, 설측교두와 근심변연에 총 170 N의 하중 (Load-3)을 가하였다. 세 가지의 하중조건 하에서 각 수복물에 따른 협측과 설측의 치경부 그리고 교합면의 정중구에서 나타나는 인장응력의 분포양상을 ANSYS 프로그램으로 분석하여 다음과 같은 결과를 얻었다. 1.모든 수복물의 경우에서 Load-1에서는 설측의 치경부, Load-2에서는 협측의 치경부에서 높은 응력이 관찰되었고, 수복물 종류에 따른 차이는 관찰되지 않았다. 2.모든 수복물의 경우에서 교합면의 하중점 근처와 정중구를 따라 높은 응력이 관찰되었고, 수복물 종류에 따라 약간 의 차이가 관찰되었다. 3.모든 수복물의 경우에서 Load-3에서는 하중점 근처에서 높은 응력이 관찰되었고, 수복물 종류에 따른 차이는 관찰되지 않았다. The purpose of this study was to investigate the effects of four restorative materials under various oclusal loading conditions on the stress distribution at the CEJ of buccal. palatal surface and central groove of occlusal surface of endodontically treated maxillary second premolar, using a 3D finte element analysis A 3D finite element model of human maxillary second premolar was endodontically treated. After endodontic treatment, access cavity was filled with Amalgam, resin, ceramic or gold of different mechanical properties A static 500N forces were applied at the buccal (Load-1) and palatal cusp (Load-2) and a static 170N forces were applied at the mesial marginal ridge and palatal cusp simultaneously as centric occlusion (Load-3). Under 3-type Loading condition, the value of tensile stress was analyzed after 4-type restoration at the CEJ of buccal and palatal surface and central groove of occlusal surface Excessive high tensile stresses were observed along the palatal CEJ in Load-1 case and buccal CEJ in Load-2 in all of the restorations. There was no difference in magnitude of stress in relation to the type of restorations. Heavy tensile stress concentrations were observed around the loading point and along the central groove of occlusal surface in all of the restorations. There was slight difference in magnitude of stress between different types of restorations. High tensile stress concentrations around the loading points were observed and there was no difference in magnitude of stress between different types of restorations in Load- 3.

高血壓患者에서 血壓降下劑에 의한 赤血球膜 Na-pump의 變化

鄭政九,昔廷鎬,李載欣 충남대학교 의과대학 지역사회의학연구소 1988 충남의대잡지 Vol.15 No.2

In the essential hypertensive patients, to study the effect of antihypertensive agents on the Na-transport mechanism across the cell membrane, we carried out the experiments of ouabain sensitive Rb-uptake and furosemide sensitive Rb-uptake in the erythrocytes. In the erythrocyte of normotensive persons, major Rb-transport systems were the ouaba sensitive pathway(Na-pump, 77%) and furosemide sensitive pathway(Na/K-cotransport, 15%), In the erythrocyte of hypertensive patients, the activity of Na-pump was reduced(40%) and Na/K-cotransport system was also inhibited(40%) with the administration of diltiazem and propranolol to the hypertensive patient for 3 or 4 months, inhibited activity of Na-pump was increased but inhibited Na/K-cotransport system was not recovered. From this results, it is suggested that it is possible to recover the decreasel Na-pump activityin the erythrocyte of hypertensive patient by the administration of several antihypertensive agents.

초등학교 체육전담교사제와 학급담임제에 따른 학생체력 비교

이정흔,김동준,안정훈 忠南大學校體育科學硏究所 1998 體育科學硏究誌 Vol.16 No.1

This research has been done to compare how much difference there is between their physical strength, after a physical educator has instructed 100 students (50 boys and 50 girls) ans a homeroom teacher has instructed another 100 students (50 boys and 50girls) for 9 months, who are the fifth grade students of an elementary school located in the city of Yong in The research result is as follows: 1) In case of the 100m race, the boy students instrected by a physical educator were superior to the students instructed by a gomeroom teacher by 1,44 seconds, and the girl students. by 1.81 seconds. 2) In case of the standing-long-jump, the boy students instructed by a physical educator were superior to the students in instructed by a homeroom teacher by 19.1 centimeters. and the girl students, by 11.8 centimeters 3) In case of the 600m race, the boy students instructed by a physical educator were superior to the students instructed by a homeroom teacher by 0.68 second. and the girl students, by 0.73 second. 4) In case of the ball throwing, the boy students instructed by a physical educator were superior to the students instructed by a homeroom teacher by 2.2 meters, and the girl students. by 4.1 meters. 5) In case of the boys pull up, the boy students instructed by a physical educator were superior to the students instructed by a homeroom teacher by 2.1 times, and in case of the girls' flexed arm hang, by 5.4seconds. 6) In case of the sit ups, the boy students instructed by a physical educator were superior to the students instructed by a homeroom teacher by 5.1 times, and the girl students. by 13.8 times. According to the above result, the students instructed by a physical educator were superior to the students by a homeroom teacher in all kinds of examination of physical strength. These superior records are because a physical edycator has instructed the students in the systematic and national based on a technical knowledge and given them a proper motivation. On the other hand the students by a homeroom teaher have neglected athletic classes because of main subjects and he has not given them a proper motivation because he doesn' t have enough technical knowledge. The physical educator system has not been activated because of the problems such as the unpreparedness of a physical educator training system. the ignorance of the persons concerned. the persistence of the homeroom teacher system. and the lack of an administrative support/but the elementary school physical educator system has to spread throughout the country and we have to help children improve their physical strength and achieve their balanced bodily structure by this system.

朝鮮朝時代의 遊戱에 對한 考察

李政欣 忠南大學校體育科學硏究所 1988 體育科學硏究誌 Vol.6 No.1

A study of the historical developments of pastimes reveals how the people of a specific era adapted themselves to their society and what characteristics their society had. This treatise is aimed at understanding what kind of pastimes prevailed in the Chosun era and how they were developed by analyzing the historical records available and the previous works in this field. The conclusion reached is as follows: Pastimes or recreational activities seem to have originated from primitive ballad dance which was a heaven-worshiping ritual. Since then, a number of pastimes have been added or have vanished as history developed and progressed. Most of these pastimes began to prevail in the period of Three Kingdoms in this country. They were succeeded and developed through the periods of Unified Shilla, Koryo and Chosun Kingdoms. In the period of Chosun Kingdom, society was highly and strictly stratified. Confucian ideologies dominated the society of this period, calling for the recreational activities different from those of the former eras. The pastimes of the Chosun period can be characterized by the fact that the pastimes enjoyed by the upper class were quite different from those of the lower class. Another feature is that the Hideyoshi Invasion in 1592 and the Manchu Invasion in 1635 played an important role in dividing pastimes into those of two periods. The pastimes before the Wars are termed the former period pastimes while those after the wars the latter period pastimes. The experience of the Wars prompted common people to engage in the recreational activities of the upper class, which were largely connected with martial arts. These arts, which were taught to common men during the Wars. continued to exist as recreational activities of the latter period. The latter period pastimes are characterized by the fact that there was a considerable increase in the number of “collective pastimes in this period and that under the influence of the Confucian teachings that regarded the military as inferior, the recreational activities originating from martial arts gradually declined. There are necessarily many problems in classifying various pastimes into certain types. However, attempts have been made to classify them according to their characteristic. It was found out that the upper class people enjoyed ball-hitting, bar-striking, kite-flying, equestrian skills, pot-throwing, sung-kyongdo and playing chess and paduk and that the lower class people indulged in playing yut, kite-flying, tug of war, riding on the swing and on-board jumping. Shuttlecock-kicking, taekwon, wrestling and stone-throw wargame were enjoyed by men while women played marbles, rode on the swing and enjoyed on-board jumping. Kite-flying and tightrope walking belonged to individual pastimes; wresting, chess and paduk to matching pastimes and stone-throwing wargame, shuttlecock-kicking and tug of war to collective pastimes. However, some of the recreational activities belong to more than one category and others are shared by different classes and by both sexes, which fact makes it even more difficult to classify various types of pastimes.

르네상스 시대의 체육에 관한 考察

李政欣,吳廷煥 忠南大學校體育科學硏究所 1991 體育科學硏究誌 Vol.9 No.1

By now, centering on the Renaissance, its background, the change of the educational idea the current situation of those day's spots were considered, and summaries were follows. (1) The Renaissance was from the start of this campaign to the Reformation-i. e. about 20 decades from 14C to 16C. This was the important age when the human dignity and personality were again recognized escaping from the medieval Dark Ages and to open the new ages, modern times to the western world. (2) After the start of the renaissance, the medieval society become to meet the new situation. To the idea, humanism to revive the culture of Greece and Rome came up, science had been developed, and arts had reached to the best. And, there was the geographical revolution to find new continents. there had been high concerns for anatomy and the public health, and there academic achievements in their own way. (3) Among them, the development of pedagogy was worthy of close attention. Humanists of those days were almost emphasized the education escaped from the medieval system, basically started from the viewpoint to make human to be human. They deeply recognized about the sports were the essential condition to make a human mind and body to develop in balance. Pethar Feltrei, Casterglione and Erasmus were representatively listed. (4) The sports which were favored in school or among citizens in the Renaissance showed to develop in sports and characters far from comparing to the medieval ages, and it was certain that these were the start of recent sports and these became the uterus for the various modern sports. To the sports of the Renaissance, there were ball games such as soccer, tennis, Schulr and golf and so forth and athletic sports such as racings and Jumpings, and there also were grapple arts such as wrestling, boxing etc. And, matches on horse and horsemanship were in grapple arts such as wrestling, boxing etc. And matches on horse and horsemanship were in the spotlight as the sports of a nobles, and swimming and rowing were also much in vogue, various military arts including fencing were continuously trained, were esteemed to be stressed on the character as a part of a sports and a self-defensing arts than an aspect of a combat-force improvement. And, dancing were prosperous, and large prospertity of a entertainment and a recreation could be expressed as an out bust of a Renaissance spirit. Entertainment and recreation, that fulfilled the entertainment nature human had and made a human life rich were esteemed as an important action coinciding exactly with a Renaissance spirit. (5) The Renaissance had the meaning as an opportunity to open the gate of changing recent modern ages of the Reformation and the Industrial Revolution. If it was compared in the sports Idea that was performed detailed studies how it was changed and transferred to the modern sports present situation since then, the appearance of the Renaissance sports were esteemed to be more certain.

태권도 선수의 정신력형태 비교분석

이정흔,임종은,이재봉 忠南大學校體育科學硏究所 1997 體育科學硏究誌 Vol.15 No.1

The purpose of this study is to analyze the mental forms of Taekwondo players who attended 97. National contest. For this study, Loehr ' s(1982) mental power guestionair was used into 180 men and 164 women in the view of sex, school background, prize career and practice career. The conclusions are like the followings. 1. Analysis result between men(n=190) and women (n=164) was meaningful in the confidence factor, visualization, image factor and Taekwondo control factor. 2. Mental form analysis result of high school players(=180) and University players (n=164) was meaningful in intention control factor, image and visualization(P<,05) high school players showed higher grade in intention control factor than male University players, but vice versa in image and visualization. 3. In the comparison of superior players(n=162) with inferior players(n=188), superior players showed more meaningful difference in confidence factor, visualization, image and attitude control factor than inferior players statistically. 4. In the comparison of practice career (under years(n=92) 5-7 years (n=108) over 8 years (n=154), the factors that showed increased grade as much as practice career were confidence factor, visualization, image factor, active energy factor and attitude factor, but not in disenchantment level, intention control factor and motivation factor. Applying ANOVA, confidence, intention control, image, visualization factor and attitude control factor showed meaningful difference(P<,05, P<.01)

고려시대 체육에 관한 考察

李政欣,申陽燮 忠南大學校體育科學硏究所 1991 體育科學硏究誌 Vol.9 No.1

By now, the actual situation of the sports of Koryo Ages and it's summaries are follow. (1) Koryo Ages was the middle ages of Korea and connected the Lee Dynasty to the Unified silla. Though Koryo had various hard such as the Military Upheval, foreign imvades and more, it could be said to keep the nation without losing the national identity. (2) To the social characterstics of Koryo Ages, the Literal-First-Military-Second trend such as the abrogation of military test, the carrying out of national events such as the Lotus Light Festival and the Eight Relationship Festival, and the prevalence of public entertainments could be listed. And almost public events were concentrated on national holidays such as the Seol, the First full moon day, the Eano, the Yudu, the Chusok, and the Winter solstice. (3) Sports of Koryo Ages could be classified in 3 of military arts, games, and entertainments. In case of military arts. the classical one was succeeded, however, Soo Jun and Arts on Horse were estimated to be created in Koryo Ages. To see the recommended sports in Koryo Ages, many games similar to the sports of modern viewpoints were founded. The one of represented was Gyeokgu. Gyeokgu had the properties such as the securing of a field, the diversity of game skills the use of a stick or a bow, and the attracting of an audience and was never considered to be inferior to the other sports events of modern and more, there was the traditional game, Soo Bak Hee. The entertainments that had been favored in Koryo ages were Hawk hunting, Too Ho, and Seok Jon Hee, the tactic ones and other general ones: almost traditional ones were considered to be formed during that period (4) In the study on th sports activity of Koryo Ages, the limit was felt was that the historical data concerned were too weak. In future, further systematic study related to sociology, folklore, and pedagogy was seemed to be needed.

유아놀이에서 나타나는 언어세계에 대한 의미 탐구

오정희,임부연 부산대학교 보육종합센터 영유아보육연구소 2008 영유아보육연구 Vol.14 No.-

Young children's world of language is fill with fresh and joyful sign. Play is one of the most significant context to reveal young children's language. This study attempts a phenomenological exploration on the meaning of children's language during play time. This study used phenomenological skills to observe 30 children's distinctive ability of using language during free play time in 5 year-old class at a kindergarten located in P city area. The data collected through 30 times of observation include observation note, in-depth interview with classroom teachers, and researcher's field note. The result showed that young children make rich the world of meaning to use and produce language in play time. The children knew what are the rule of play through insight and they create rules of play. They were also able to deconstruct and reconstruct signs by using imagination and metaphor which are the most powerful symbol of consciousness in early childhood period. This study discussed that early childhood teachers should be more careful to listen and respect children's own language which is not a measure of development or fuction but an expression of inner world.

투스텝 수직점프와 제자리 수직점프시 각 신체 분절의 기여도에 관한 연구

이정흔,오정환 忠南大學校體育科學硏究所 1995 體育科學硏究誌 Vol.13 No.1

The purpose of the study is to compare the contribution factors of two step jump with those of the original place vertical jump at the instant of each jump by three mentional imaging analyzer for undergraduate students. All of the results are followed as; 1. At the instant of two step vertical jump, taken time of the weight interval was shot. 2. Line speed of the body segment was appeared hands, forearms, respectively at the instant the original place vertical jump, the speed of forearms was faster than that of hands. 3. The angle of each joint appeared greater at the instant of two step vertical jump than at the instant of the original place vertical jump when arms positioned backswing. 4. The angle speed of the joint was appeared hip joint, knee joint, ankle joint, respectively at the instant of the original place vertical jump, but the angle speed of the arm was appeared the fastest of all. 5. The vertical speed of body center was appeared fater at the instant of two the original place vertical jump. 6. The ground reaction force was appeared greater at the instant of the original place vertical jump than at the instant of two step vertical jump. 7. The inertial force exerting each segment was appeared the lower leg, the thigh, the foot segment, respectively, at the instant of the original place vertical jump and two step vertical jump. 8. At the instant of the original place vertical jump and two step vertical jump, hands, forearms, brachium, trunk, and head didn't propell toward vertical upward, but they reacted against upward of the vertical by the weight of each segment. 9. At the instant of the original place vertical jump and two step vertical jump, inertial force exerting at each segment was appeared to help the vertical upward movement in the foot segment, and the thigh segment

CAN 통신을 위한 Windows 환경에서의 가상 디바이스 드라이버 개발

최흔정,김대원 明知大學校 産業技術硏究所 2000 産業技術硏究所論文集 Vol.19 No.-

The CAN(Controller Area Network) of fieldbus for factory automation is sensor level protocol using the lower two layers of seven layers defined by ISO(International Standard for Standardization). It is necessary to design the application layer. It includes the communication scheduling of CAN network and the integrated environment for monitoring it to design the application layer. It is implemented under the Windows operating system of Microsoft to construct integrated environment for CAN network. Designing PC interface card and the virtual device driver for it are done before constructing of the integrated environment for CAN network. This paper presents the design of PC interface card, the virtual device driver for it, and the definition and implementation of the integrated environment for CAN network.