단방향 네트워크의 신뢰도 계산에 관한 연구

정지안,조성구 동국대학교 산업기술대학원 1993 산업기술논문집 Vol.1 No.-

This study presents a reliability computation method for directed networks with unreliable components. The unreliable components' failure probabilities are assumed to be known and statistically independent. The computation method is essentially composed of two steps.In the first step, the possible inverse paths from the terminal node are searched for and simultaneously parallelized at each stage. This process is continued until the source node is finally reached. In the second step, the network reliability is calculated from this parallelized diagram by producing disjoint terms composed of all components. The reliability expressions can be directly obtained from these disjoint terms. In order to verify this suggested method, the reliability of an example network given in reference is calculated. The results show that this method requires a relatively small amount of calculation. However, it is found out that the method cannot be applied to all network types. In this respect, the future research should be one that enhance the applicability of the suggested method to other type of networks.

골수 이식을 받은 만성 골수성 백혈병 환자의 Tc-99m MDP 골스캔에서 우연히 발견된 비장 Hemochromatosis

안병철,서지형,배진호,정신영,이재태,이규보 대한핵의학회 2004 핵의학 분자영상 Vol.38 No.1

Purpose: Tc-99m MDP bone scan was performed to evaluate a generalized bone pain in a 24-year-old male chronic myelogenous leukemia patient who received bone marrow transplantation at 7 months ago. The patient had received large amounts of blood transfusion for managing symptoms related to anemia. Bone scan revealed substantial splenic tracer uptake. Magnetic resonance image and laboratory evidence of hemochromatosis suggests that the presence of large quantities of iron in the spleen of this patient may have been responsible for the splenic uptake of the bone scanning agent. The authors report a case of splenic hemochromatosis incidentally found on Tc-99m MDP bone scan.

컴퓨터 게임에 대한 학부모·교사·학생간의 인식의 차이에 관한 연구 : 부산광역시 중학교 남학생을 중심으로

안성진,김영환,정지언 부산대학교 과학교육연구소 2007 교사교육연구 Vol.46 No.1

본 연구의 목적은 컴퓨터 게임에 대한 청소년과 그들의 교사, 학부모의 인식을 조사하여 각 집단별 인식 간에 차이가 있는지, 있다면 어떤 영역에서 가장 큰 차이를 보이는 지를 알아보는 것이다. 이를 위해 남자 중학생 297명, 이들의 교사 124명, 학부모 278명을 표집하여 컴퓨터 게임시의 자기 통제력에 대한 인식, 컴퓨터 게임이 학습활동, 교우관계, 부모님과의 관계, 자아존중감, 건강에 미치는 영향에 대한 각 집단별 인식의 차이를 분석하였다. 연구결과를 보면, 중학생들은 대체적으로 컴퓨터게임에 대해 긍정적으로 인식하고 있었다. 컴퓨터 게임은 스트레스 해소를 위해 가장 필요하고, 성적에는 별로 영향을 주지 않는 것으로 인식하고 있었지만 교우관계에는 부정적 영향을 주는 것으로 보고 있었다. 교사들은 대체적으로 컴퓨터 게임이 중학생들에게 부정적으로 작용한다고 보고 있었다. 특히 게임에 대한 자제력 부족으로 성적에 부정적인 영향을 줄 것이고 이로 인해 학부모들과 갈등이 초래될 것으로 인식하고 있었다. 부모들은 대체적으로 교사보다는 긍정적으로, 그러나 학생보다는 다소 부정적으로 컴퓨터게임에 대해 인식하고 있었다. 교사들은 컴퓨터게임이 학생과 학부모의 관계형성에 부정적일 것으로 보고 있었으나 실제 학생과 학부모들은 그렇지 않은 것으로 나타났다 Generally, the middle school students play the computer games in their spare times or for pleasure. But, their parents and teachers emphasize on the negative effect of the computer games and restrict the students to play the games. This difference comes from different standpoints on the computer games among parents, teachers, and students. In this context, this study aims at investigating the different views of the computer games among parents, teachers, and students. Regarding a view of the computer games, this thesis puts it as being influenced by the conditions of the self-control on playing the computer games, the students' associates, the relations between the students and their parents, the self-respect, and the health. According to the results, the middle school students play the computer games in forty three percent of their leisure times for pleasure and getting rid of stress. In addition, they can not find an alternative but the computer games in their spare times. As to the difference of the views on the computer games, the middle school students and the parents are positive but the teachers are not. The students are the most positive of the computer games. In particular, they take the affirmative to the self-control on playing the computer games and the effect on their health, but regard the computer games as keeping bad company. The teachers have the most negative assertion toward the computer games. Mostly, except the students' associates and self-respect, the teachers do not agree to the computer games to bring positive effect on the students. Comparatively, the parents are positive of the computer games but less than the students are. They believe that the computer games have the positive effect on the self-control on playing the computer games and the students' health. Nevertheless, they make an negative assertion in relations to the learning and the students' associates. Therefore, this study is able to form a conclusion that it might be needed for the parents and teachers who have the negative attitude toward the computer games to put themselves in the position of the students to find the positive effects of the computer games and suggest appropriate guidelines for the students as maximizing positive effects of the computer games.

유아용 시럽형 약물이 구강 내 산도에 미치는 영향

안지영,김재문,정태성,김신 大韓小兒齒科學會 2007 大韓小兒齒科學會誌 Vol.34 No.4

Syrup form medicines which children commonly take contains sugar as sweeteners. Sugar, low endogenous pH, high acidity, mucosity and low concentrations of ions including those of calcium, fluoride, and phosphate in their composition, they can be cause of caries and erosion. Not only the properties found in such medicines. but also other factors such as high frequency of ingestion, bedtime consumption, and the collateral effect of a reduction in salivary flow, poor oral hygiene of sick children may also contribute to the risk. The other side, parents rarely recognize these risk, and medical experts also easily overlook. The purpose of this study was to investigate the pH level of some syrup form medicines which are frequently administered by infants and young children, and their effects on the changes of plaque pH when rinsing with them. And we compared the salivary pH change induced by rinsing with Cough-syrup only and rinsing with Cough-syrup followed by water. The results were as follows : 1. The average pH of syrup form medicines which were prescribed in Pusan National University Hospital and several OTC syrup form medicines was pH 4.7±0.94, within the range of pH 3.0 to 6.8. 2. The plaque pH decreased rapidly below pH 5.5 after rinsing with the syrup form medicines which were selected for the test and there was no statistically significant difference in the of plaque pH change between syrup form medicines except C0LDI(p>0.05). 3. There was statistically significant difference in salivary pH change between rinsing with Cough-syrup only and rinsing with water after Cough-syrup(p<0.05). 유아용 시럽형 약물은 어린이가 쉽게 복용할 수 있도록 여러 종류의 당분을 감미제로 사용하고 있으며 그로 인한 우식의 위험이 높다고 할 수 있다. 그러나 시럽형 약물의 우식유발성에 대한 보호자의 인지도는 매우 낮으며 의료 종사자들 조차 이를 소홀히 여기고 있어 문제의 심각성이 크다고 할 수 있다. 본 연구는 시럽형 약물이 구강 내 산도에 미치는 영향에 대하여 조사할 목적으로, 15 종의 시럽형 약물의 산도를 조사 하고,그 중 널리 시판되는 4종을 선택하여 이 약물들이 치태의 산도 변화에 미치는 영향을 평가하였다. 또한 가장 흔하게 사용하는 유아용 시럽형 약물의 일종인 코푸시럽의 복용방법에 따른 타액의 산도 변화를 측정하여 다음과 같은 결과를 얻었다. 1. 15 종 시럽형 약물의 산도는 pH 3.0∼6.8의 범위에서 다양하여 평균 pH 4.7±O.94로 나타났다. 2. 치태의 산도변화를 측정하기 위해 선정된 4종의 시럽형 약물 모두는 구강 내 투입 직 후 법랑질의 탈회 임계점인 pH 5.5 이하로 치태의 산도를 급격히 떨어뜨렸으며,시간 경과에 따른 치태의 산도 변화에서 콜디(종합 감기약)를 제외한 모든 약물에서는 유의한 차이가 없었다(p>O.05). 3. 코푸 시럽으로 구강을 행구어낸 경우와 코푸 시럽에 이어 물로 구강을 행구어낸 경우 타액의 산도 변화에 있어서는 유의한 차이가 있었다(p<O.05).

하악에 전이된 위 선양암종

이지운,권기정,안현숙,고광준 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.3

Metastatic tumors to the jaw bones are uncommon. The most common metastatic tumors to the jaw bones are the breast, lung and kidney. In the jaw bones, the common location of the lesions is the mandible, and the posterior area of the mandible is more commonly affected. The radiographic appearance is quite variable. In this report, a very rare case of metastatic gastric adenocarcinoma to the mandible is presented. The patient had undergone a gastrectomy 3 years ago.

자매 관계에 따른 의복행동

박지은;안홍선;정세희 한양대학교 2012 韓國 生活 科學 硏究 Vol.32 No.1

This research set the big three research-questions in order to find out how sister-relations influence on clothing-consumer sentiment and behavior. The purpose of this study was to analyze the difference of clothing-consumer sentiment and behavior according to Sisters` order of birth; toanalyze sister-relations` influence on the sharing of clothes; to analyze the extent of sisters` sharing clothes and ownership. As a result, when they have older sisters, sister-dependence of decision making is high and attitude about sharing is positive. Also the actual number of sharing clothes is more than the case of having younger sisters. Moreover when intimacy of sisters is high and their body-shapes and styles are similar, they share clothes more. Also sharing extent of outers and accessaries is high according to the less gap between sisters` age. Sharing clothes of sisters is high in T-shirts, accessaries and outer wear and ownership is indefinite when they share clothes a lot. In short, it shows that sister relations and clothing-consumer sentiment and behavior are related.

유사성-매력 연구에서의 논쟁점들 : 개관

김지정,안신호 심리과학연구소 2005 심리과학연구 Vol.4 No.-

The relationship between similarity and attraction has been supported strongly by various literatures. These studies have consistently demonstrated that the greater the similarity between two persons, the greater is their attraction to each other. In spite of powerful supporting, many arguments with respect to similarity-attraction have been raised. Similarity-attraction studies have been mainly focused on the attitude similarity, Therefore, it could have a limitation to apply these theories to the similarity and attraction linking. Accordingly, the present study review controversies over similarity-attraction studies, and then suggest directions for further studies about similarity-attraction. 유사성과 매력의 관계는 여러 연구들에 의해 강력하게 지지되어 왔다. 이 연구들은 사람들은 자신과 유사한 속성을 가지고 있는 사람을 좋아한다는 결과들을 보여주고 있다. 강력한 지지에도 불구하고 유사성-매력 연구의 여러 측면에서 문제가 제기되었다. 주로 태도 유사성을 다루는 연구가 대부분이었기 때문에 이 연구들에서 나온 결과를 유사성-매력 관계로 일반화시키는 것은 문제가 있다. 따라서 본 연구는 지금까지 유사성-매력 연구에서 쟁점이 된 문제들을 개관하고, 이후 연구의 방향을 제시하고자 한다.

말기신부전 환자에서 혈액투석 전후의 QT간격분산 비교

강대웅,정지용,윤나라,안치용,김종오,신병철,정종훈,김현리 朝鮮大學校 附設 醫學硏究所 2006 The Medical Journal of Chosun University Vol.31 No.2

Background: Some cases of QT interval, corrected QT interval (QTc), QT dispersion (QTd) and corrected QT dispersion (QTcd) have been reported in ESRD, but these results are variable and the influence of a hemodialysis is still controversial, In this study, we investigated the effect of hemodialysis on QT and QTc interval and QT and QTc dispersion in patients with ESRD 15 min before and 15 minute after each hemodialysis. Methods: Sixty-seven patients with ESRD (men 33 & women 34) on three-times stable hemodialysis (>3 months) were randomly enrolled. Fifty control subjects with a similar age and normal renal function were enrolled from this hospital. Routine biochemical studies were measured pre- and post dialysis, at the time of the ECG. Plasma Na+, K+, BUN, creatinine, ionized calcium and phosphate were checked. Twelve-lead electrocardiographs were performed at 10㎜/mv and 50㎜/s using a HewIett-Packard Pagewriter 100, before and after a single hemodialysis session.The QT interval was measured from the onset of the QRS complex to the end of the T wave. If the end of the T wave was not clear in a particular lead then it was excluded from analysis. When U waves were present, the end of the T wave was taken as the nadir between the T and U waves. Each QT interval was corrected for heart rate using Bazett's formula (QTc==QT/√(RR)) (ms). The difference between maximal and minimal QT interval duration was defined as QT dispersion (QTd) in each of the 12 leads. Result: This study demonstrates that QT, QTd, QTcd is higher in hemodialysis patients compared with control subjects, and QT and QTd rise postdialysis to levels comparable to those seen acutely following myocardial infarction, when patients are at greatly increased risk of potentially fatal ventricular arrhythmias, Conclusions: QT interval and QT dispersion, markers of risk for arrhythmias and sudden death, are elevated in hemodialysis patients, and rise postdialysis. QT interval and QT dispersion is an easily obtainable, noninvasive, simple, inexpensive, and widely available method of risk stratification in uremic patients receiving chronic dialysis. Additional studies are needed to clarity whether increased postdialysis QT dispersion results in an increased occurrence of arrhythmias.

국내에서 분리된 Extended-Spectrum β-Lactamase 생성 Escherichia coli와 Klebsiella pneumoniae의 빈도 및 유형

홍성근,김선주,정성훈,장철훈,조성란,안지영,신종희,이혜수,송원근,어영,염종화,용동은,이경원,정윤섭 대한임상미샐물학회 2003 Annals of clinical microbiology Vol.6 No.2

난소절제후 Estrogen을 투여한 흰쥐 대동맥에서 Protein Kinase C-α와 Fas 발현의 변화

이왕수,이상엽,안지현,송영빈,김학진,이광재,유재격,김상욱,김태호,김치정,류왕성 중앙대학교 의과대학 의과학연구소 2001 中央醫大誌 Vol.26 No.3

Estrogen is believed to decrease coronary artery disease. Protein kinase C-α(PKCα)appear to be important in signal conduction pathways. Estrogen treatment increases catalytic activity of PKCα,and activation of PKCαcan modulate estrogen receptor levels and responsiveness. And it was reported that activation of PKC can protect cells from apoptosis induced by Fas ligation. But the beneficial effect of estrogen on PKCαwas not clearly demonstrated. The objective of this study was to evaluate the role of PKCαafter ovariectomy and estrogen therapy in rat aorta. The results were summarized as below: 1. The significant pathological changes were not observed in the rat aorta irrelevant to ovariectomy and estrogen therapy. 2. The expression of Fas was decreased in the aorta of estrogen-treated rats than that of ovariectomized rats without estrogen therapy. 3. Increased expression of PKCαwas more marked in the aprta of estrogen-treated rats than that of ovariectomized rat without estrogen therapy. In conclusion,PKCαmay be important in signal conduation pathway on the effect of estrogen. Activation of PKCαby estrogen reduced Fas expression, suggesting that PKCαactivation may play a role in protection against atherasclerosis. Further studies are needed to elucidate the role of PKCαafter estrogen therapy.