위치정보를 이용한 최단경로탐색 알고리즘 개선

이종현,강민제,이상준 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.2

The shortest path problem arises whenever we try to determine the shortest, cheapest, or most reliable path between one or many pairs of nodes in a network. The path search algorithm for the CNS(Car Navigation System) process the actual road map with complex data and should return the result within acceptable response time. In this paper. we studied the improvement of existing shortest path algorithm using the positioning information. The proposed algorithm was analyzed by the simulation with the real road map data in Jeju city. From the simulation result, it is known that the proposed algorithm required less memory usage and less computational time than the others.

원발성 간암종의 조직 발생에 대한 면역조직학적 연구

강대영,최정목,송규상,이헌영 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To assess the utility of cytokeratin(CK) profile in the differential diagnosis of primary liver carcinomas(PLCs),we evaluated a series of needle biopsied specimens and surgically resected PLCs, comprising 30 pure hepatocellular carcinomas(HCCs) and 20 cholangiocarcinomas(CCs). The results are summarized as follows: 1) The pure hepatocellular carcinomas showed intense cytoplasmic expression of anti-cytokeratin (AE1/AE3);28/30 (93.3%). 2) The cholangiocarcinomas showed cytoplasmic expression of 2 types of CK(Anti-CK19,AE1/AE 3);14 of 20 (70.0%) of the CCs evidenced mature bile duct phenotype (CK 19), whereas 10 of 20 (50.0%) displayed the hepatocytic profile(AEl/AE3). 3) Nine of 30 HCCs also displayed the bile duct cell profile; high grade HCCs(8/20), and low grade HCCs(1/10). The above results show that a mixed biological phenotype can be found both among morphologically pure HCCs and peripheral CCs, suggesting that these two forms could share a common histogenesis.

급성 담낭염에 대한 내과적 치료의 역할

강성원,조한래,한설해,박현주,정인성,홍선미,김성걸,이헌영 충남대학교 의과대학 지역사회의학연구소 1993 충남의대잡지 Vol.20 No.2

In 58 patients who were admitted to department of internal medicine, ChungNam national university hospital from January 1989 to March, 1993. We evaluated for medical treatments and the following results were obtained. 1) The ratio of male and female was 1 : 1 and mean age of the patients was 57.4 years. 2) At arrival on hospital, the most common clinical symptom was pain in right upper quadrant and epigastrium(93.1%), the remainders were fever and chill(79.3%), nausea(51.7%) and vomiting(36.2 %) in order of frequency. 3) The most common physical findings was tenderness on the right upper quadrant and epaigastrium(98%), the remainders were jaundice(50%) and palpable gall bladder(13.8%) in order of freguency. 4) In laboratory examination, elevated levels of ESR(82.8%), leukocytosis(67.2%), elevated levels of AST(62.0%), ALT(50.0%), serum total bilirubin(51.7%) and alkaline phosphatase (43.1%) were noted. 5) The mean period of NPO was 3.9 days and the mean hospital period was 13.5 days. 6) The rates of combined complications in patients with acute cholecystitis were 17.2%; these are gall bladder empyema(5.2%), hydrops(5.2%), perforation(3.4%), sepsis(3.4%) and intestinal obstruction (1.7%). 7) In 96.6 percent of 58 cases, the symptoms of acute cholecystitis were improved by conservative management. 8) The mean follow-up period was 25.5 months and the recurrence rate was 10% during this period.

횡하중을 받는 SiC/Ti-15-3 MMC 복합재 계면영역에서의 탄소성 응력장분포거동(Ⅰ)

강지웅,김상태,권오헌 한국안전학회 2004 한국안전학회지 Vol.19 No.4

Unidirectional fiber-metal matrix composites have superior mechanical properties along the longitudinal direction. However, the applicability of continuous fiber reinforced MMCs is somewhat limited due to their relatively poor transverse properties. Therefore, the transverse properties of MMCs are significantly influenced by the properties of the fiber/matrix interface. In this study, the interfacial stress states of transversely loaded unidirectional fiber reinforced metal matrix composites investigated by using elastic-plastic finite element analysis. Different fiber volume fractions (5-60%) were studied numerically. The interface was treated as three thin layer (with different properties) with a finite thickness between the fiber and the matrix. The fiber is modeled as transversely isotropic linear-elastic, and the matrix as isotropic elastic-plastic material. The analyses were based on a two-dimensional generalized plane strain model of a cross-section of an unidirectional composite by the ANSYS finite element analysis code.

호산구성 간농양 54예의 임상상

강혜련,권혁수,송우정,이상민,김태범,박혜경,장윤석,김윤근,조상헌,민경업,김유영 대한알레르기학회 2004 천식 및 알레르기 Vol.24 No.2

불평형 전원전압을 갖는 정류시스템에서 출력필터에 따른 입력 특성 분석

강수현,김상훈 강원대학교 산업기술연구소 2005 産業技術硏究 Vol.25 No.B

The rectifier characteristics and the quality of the input current worsens with the increase of unbalances or harmonics of the supply voltages. Rectifier input current harmonics interfere with proper power system operation, reduce rectifier power factor, and limit the power available from a given source. It is of importance to select appropriately the rectifier's outpur filter inductance to determine the rectifier input current waveform, the input current harmonics, and the power factor. This paper presents a quantitative analysis of single and three phase rectifier input current harmonics, total harmonic distortion, and power factor as a function of the output filter inductance under balanced and unbalanced conditions. Also, its performance under the supply voltage including harmonics be investigated. These results provide a reference for selecting resonable rectifier's output filter inductance for given harmonics or power factor criterion.

내시경적 점막절제술로 치험한 식도 과립상 세포종 1례

강혁주,김성욱,최석진,이중현,장재식,서영범,윤병구,박건욱,김성자,김용섭,강승완,이구,양창헌,이창우,김욱년,이광헌,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

과립상 세포종은 Schwann 세포 기원으로 생각되며 인체에 비교적 드물게 발생한다. 과립상 세포종은 전신 어느 곳에서나 발견될 수 있으나 주로 혀, 구강, 피부 혹은 유방 등에서 호발하며 드물게 위장관에서 발견된다. 위장관에서는 식도에서 가장 호발하며 다음으로 위, 대장 순이다. 과립상 세포종은 대부분, 특히 위장관에서는 양성이며 소수의 악성 병변이 보고되었다. 이러한 이유와 함께 수술 전의 진단이 어렵기 때문에 과립상 세포종에 대한 근본적인 치료는 현재까지 외과적 절제술이다. 최근에 시도되는 치료방법들로는 내시경적 레이저 치료, 용종절제술, 내시경적 점막 절제술 등이 있다. 저자들은 상부 소화관 내시경검사를 시행하여 식도 과립상 세포종을 진단하고 내시경적 점막 절제술을 시행하여 합병증 없이 퇴원하여 현재 재발없이 경과 관찰중인 1례를 경험하였기에 보고하는 바이다. Granular cell tumors, which occur infrequently, are probably of Schwann cell origin. They can occur almost anywhere in the body but usually affect the tongue, oral cavity, skin, or breasts and are rarely found in the gastrointestinal tracts. The esophagus is the most frequent gastrointestinal site, followed by the stomach and the colon. Granular cell tumors are generally benign, especially in the gastrointestinal tract, some malignant lesions have been reported. For this reason, and also because preoperative diagnosis is difficult, the standard treatment for granular cell tumor has until now been surgical excision. In recent years, other therapeutic methods is endoscopic laser therapy (ELT), polypectiomy, endoscopic mucosal resection (EMR). We report a case of esophageal granular cell tumor which was diagnosed by an endoscopy and managed using an endoscopic mucosal resection without complication.

정신분열병의 생물학적 원인

강병조,원승희,김상헌 대한생물치료정신의학회 1998 생물치료정신의학 Vol.4 No.2

The authors reviewed the biological etiologies of schizophrenic disorder such as genetic, viral, neurodevelopmental, neural network, sunspots and cerebral diabetic hypothesis. The etiology of schizophrenic disorder remains to be confirmed. Although genetic possibilities were suggested by many investigators, the genetic genes and their transmission methods have not been clarified yet. The neurodevelopmental hypothesis was reviewed in detail. This hypothesis includes genetic hypothesis, viral hypothesis, obstetrical complication hypothesis, neutritional deficience theory, NMDA receptor hypofunction theory and neural network theory. The neurdevelopmental hypothesis means that several developmental trajectories, related to early brain insults as well as the genetic factors affection postnatal neurodevelopment, possibly lead to this illness. An excessive pruning of the prefrontal corticocortical, and corticosubcortical synapses, perhaps involving the excitatory glutaminergic inputs to pyramidal neurons, may underlie schizophrenia.

각종 치과레이저의 Streptococcus mutans에 대한 증식 기능억제 효과

한강석,국중기,유소영,김화숙,박종휘,박현동,이상훈 大韓小兒齒科學會 2003 大韓小兒齒科學會誌 Vol.30 No.3

레이저의 구강내 산 생성 세균인 S. mutans에 대한 증식 및 기능 억제효과를 평가하기 위하여 S. mutans KCTC 3065가 포함된 세균 pellet에 Er:YAG 레이저와 Nd:YAG 레이저를 비접촉식 방법으로, 조사세기 50mJ, 조사시간 5초, 그리고 pulse repetition rate를 각각 10Hz와 30Hz로 하여 조사하고 세균 군락수, 산 생성능, 불용성 세포외다당류의 합성량을 측정하여 다음과 같은 결과를 얻었다. 1. Chinese ink로 photosensitization을 시행한 후 Nd:YAG 레이저를 조사한 경우가 S. mutans의 증식을 가장 많이 억제하였으며 Er:YAG 레이저 조사도 증식을 억제하였다. Chinese ink를 사용하지 않고 ND:YAG 레이저를 단독으로 조사한 경우는 S. mutans의 증식을 억제하지 못하였다. 2. Chinese ink로 photosensitization을 시행한 후 Nd:YAG 레이저를 조사한 경우가 일정기간 동안 S. mutans의 산생성능을 가장 많이 억제하였으며 Er:YAG 레이저 조사도 산 생성능을 억제하였다. Chinese ink를 사용하지 않고 Nd:YAG 레이저를 단독으로 조사한 경우는 S. mutans의 산 생성능을 억제하지 못하였다. Er:YAG 레이저와 Chinese ink로 photosensitization을 시행한 후 Nd:YAG 레이저를 조사한 경우는 pulse repetition rate가 클수록 전반적으로 세균의 산생성능을 더 많이 억제하였다. 3. 레이저 조사는 S. mutans의 불용성 세포외다당류의 합성에 영향을 미치지 못하였다. 이상의 결과로 보아 Er:YAG 레이저와 Chinese ink로 photosensitization을 시행한 후의 Nd:YAG 레이저 조사는 일정시간 동안 S. mutans의 증식과 산 생성능을 억제시키므로써 치아우식증 예방효과를 얻을 수 있다고 사료되나 억제효과가 오래가지 않아 임상적으로 효과를 얻기 위해서는 자주 조사를 해주어야 한다는 문제점을 안고 있어 임상적으로 치아우식증 예방이란 단독 목적으로 사용하기에는 실용성이 크지 않다고 사료된다. This was performed to evaluate the inhibitory effect of laser on the growth of S. mutans. The bacterial pallets containing S. mutans KCTC 3065 were irradiated with Er:YAG laser and Nd:YAG laser by non-contact method at an intensity of 50mJ for 5 sec with the pulse repetition rates of 10Hz and 30Hz, respectively. The following results were obtained on colony count, acid producing ability, and the amount of insoluble extracellular polysaccharide synthesis. 1. The irradiation of Nd:YAG laser after photosensitization with Chinese ink inhibited the proliferation of S. mutans the most, and the irradiation of Er:YAG also inhibited the proliferation. However, the irradiation of Nd:YAG laser alone could not inhibited the proliferation of S. mutans. The pulse repetition rate did not affect significantly on the proliferation of bacteria in overall. 2. The irradiation of Nd:YAG laser after the photosensitization with Chinese ink inhibited the acid production of S. mutans the most for a certain period of time. Er:YAG laser also inhibited acid production. When Nd:YAG laser was used alone, the acid production of S. mutans was not been inhibited. The irradiation of Nd:YAG laser after photosensitization with Chinese ink inhibited the acid production ability of bacteria the most as the pulse repetition rate increased. 3. Laser irradiation did not inhibited the synthesis of insoluble extracellular polysaccharide of S. mutans. From these results, we conclude that the irradiatioin of Er:YAG laser and Nd:YAG laser after photosensitization with Chinese ink would inhibit the proliferation and acid production by S. mutans, which may prenent dental caries. However, this effect does not last long time so that the laser irradiation should be repeated frequently in order to obtain clinical effect; thus, this laser irradiation would not have a clinical usefulness in preventing dental caries when used solely.

지역사회 획득 급성 신우신장염 여성환자에서 검출된 원인균의 항균제 감수성 및 항균제의 사용

위성헌,최수미,이동건,김수영,김상일,유진홍,신완식,강문원 대한감염학회 2002 감염 Vol.34 No.6