• 한국산업보건학회지
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• 제18권2호
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• pp.149-160
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• 2008

Bag-filter system has been widely used in industrial field to remove the particulate matters from the exhaust gas. The cylindrical type of bag-filter has been generally used. But it has many shortcomings. The reattachment of separated particles on the surface of bags could result in high pressure drop of bag-filter system and subsequent decrease of air flow rate since the cylindrical type bag-filter system should have the upward flow pattern. In addition, the supply of very high pressure pulse air jet to remove particulate matters on the surface of filter could result in a frequent rupture of bags. To overcome these shortcomings of the cylindrical type, the rectangular type was developed in the developed countries and imported to Korea. But, there was not many design data available to understand the mechanisms. Thus, the fundamental experiments were conducted in this study to get some ideas about the pulse jet cleaning of rectangular type bag filter system. The experimental factors are as follows; pulse distance, pulse duration, pulse interval, pulse pressure and pulse nozzle type. Experiments followed the factorial design method. With the shorter pulse distance, the distribution of pressure drops was relatively not uniform while the particulate removal efficiency was higher. With the longer duration of pulsing and the more number of pulse nozzle, the removal efficiency was higher and the pressure drop distribution was more uniform.

• Archives of Plastic Surgery
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• 제35권3호
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• pp.289-294
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• 2008

Purpose: The nasal bone fracture is known as the most common facial fracture. Several authors reported the classification of nasal bone fracture. Stranc classified the type of nasal fractures based on a pattern of impaction and level of injuries. Stranc classification proposed here is based on careful clinical observation and relates to both treatment and prognosis. The aim of this study is to determine any predictive value to the preoperative classification of nasal fracture, using the description by Stranc and Robertson. Methods: We reviewed 310 patients with nasal bone fracture treated at our hospital for last two years. Results: Lateral impact type of nasal bone fracture predominated more than frontal impact in the ratio of 2.3:1. The most common type of Stranc classification was lateral impact plane I(48.4%). Male predominated more than female in the ratio of 3:1. The most frequent age group was first decade(27.1%), second decade in frontal impact(30.5%), first decade in lateral impact (30.7%). The most common etiology was violence (31.3%) followed by slip down(21.3%), and traffic accident(18.1 %).The most common associated fracture was orbital(22.9%) followed by zygoma(10%), and maxilla (6.1%). The most common complication was septal deviation(20.0%) in frontal impact, and nasal deformity (26.0%) in lateral impact. The incidence of nasal deformity in lateral impact(26.0%) was more higher than frontal impact(15.8%) Conclusion: By assessing the pathomechanics and resultant degree of injury to the nasal skeleton, a better understanding of the treatment plan and prognosis was obtained. Using this information, satisfactory informed patient consent can be obtained.

• 한국과학교육학회지
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• 제20권3호
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• pp.455-467
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• 2000

본 연구의 목적은 실제 과학수업에서 형성평가가 어떻게 이루어지고 있는지를 파악하는 것이었다. 이를 위하여 중학교 과학수업을 관찰, 녹화하였으며, 교사와 학생을 대상으로 면담을 실시하였다. 수업 중 형성평가가 실제로 어떻게 이루어지는가를 관찰한 결과, 형성평가는 계획된 형성평가, 상호작용 형성평가, 계획된 형성평가에서 상호작용 형성평가로의 전환으로 구분되었다. 교사들은 형성평가를 통하여 개인적 발달, 사회적 발달, 과학적 발달을 평가하였으며, 과학적 발달은 내용평가, 과정평가, 상황평가로 구분되었다. 수업 중 이루어지는 대부분의 평가는 과학적 발달평가였으며, 그 중에서도 내용평가에 치중되어 이루어졌다. 형성평가가 이루어지는 과정은 정보얻기, 판단하기, 피드백하기로 구분되었고, 이 세 과정은 서로 밀접하게 관련되며 순환적으로 이루어졌다. 또한 교사의 질문유형과 피드백의 유형은 교사와 학생의 수업 중 상호작용 정도에 영향을 미쳤다. 위의 결과는 과학 수업에서 형성평가가 학생들의 다양한 측면을 평가할 수 있어야 하며, 상호작용이 보다 활발히 일어날 수 있도록 정보를 얻는 방법, 피드백을 하는 방법 등에 있어서 보다 많은 연구와 전략의 개발이 필요함을 시사해준다.

• Journal of Korean Neurosurgical Society
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• 제30권1호
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• pp.20-25
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• 2001

Objectives : A substantial number of craniopharyngiomas recur despite gross total excision. The purpose of our study was to investigate pattern of recurrence and to verify prognostic factors for recurrence after gross total excision of craniopharyngiomas in children. Methods : A series of 36 patients with craniopharyngiomas were reviewed. All patients had undergone gross total excision and none of them received radiotherapy after initial surgery. Fifteen were girls and twenty-one were boys, with a mean age of 7.3 years(range, one to 15 years). The mean follow-up period was 52 months(range, one to 149 months). Recurrence was noted in 14 patients within 83 months(mean 31.4 months). Results : The overall three-year recurrence free survival rate was 65%, and the five-year recurrence-free survival rate was 55%. Regular neuroimaging follow-up at six to 12-month intervals detected tumor recurrence of a smaller size before symptoms developed(p<0.05). At the first surgical procedure, the optic nerve/chiasm(n=23) was the most common adhesion site. The most frequent sites of recurrence were the optic nerve/chiasm(n=6) and the pitiutary fossa(n=6). Tumor location was the single significant clinical predictor of recurrence. The five-year recurrence-free survival rate was 39% for those who had an intrasellar tumor component and 81% for those who did not (p<0.05). Conclusion : Craniopharyngiomas with intrasellar components should be followed cautiously and regular followup of patients should be emphasized, even when the tumors are totally resected.

• 한국정보통신학회논문지
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• 제10권8호
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• pp.1401-1406
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• 2006

최근 산업 및 연구단체에서 이동 Ad-hoc망에 대한 관심이 높아지고 있다. 기존 연구들은 라우팅에 초점을 맞추고 있었던 것에 반해 본 논문에서는 이들 연구의 결과로 형성된 Ad-hoc망을 실제로 이용하기 위한 응용으로 가변지오캐스팅 방법을 제안한다. 지오캐스팅 프로토콜 목적은 특별한 지오캐스팅 영역에 위치한 노드들의 그룹에 패킷 데이터를 전송하는 것이다. 본 논문에서는 Ad-hoc기반의 이동 네트워크 환경에서 지오캐스트 서비스를 지원하는 기존연구에 데이터 전송경로의 비 최적화, 빈번한 지오캐스트 전송트리의 재구성으로 인한 오버헤드, 서비스단절의 문제를 해결하기 위해 이동형태기반의 가변지오캐스팅 기법을 제안한다. 가변지오캐스팅 기법은 서비스범위를 목적지 노드의 이동성에 따라 가변적으로 설정하고 자원예약기법과 다양한 실험을 통해 이동노드의 이동성에 따른 접근성 및 네트워크 오버헤드를 줄여 성능평가 하였다.

• 한국정보처리학회논문지
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• 제7권9호
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• pp.2876-2884
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• 2000

단문분할은 한 문장에 용언이 복수개 있을 때 용언을 중심으로 문장을 나누는 방법이다. 기존의 방법은 정형화된 문장의 경우 비교적 효율적인 결과를 얻을 수 있으나, 구문적으로 복잡한 문장인 경우는 한계를 보였다. 본 논문에서는 이러한 한계를 극복하기 위해서 구문 정보만이 아니라, 의미 정보를 활용하여 단문을 분할하는 방법을 제안한다. 정형화된 문장의 경우와 달리 일상적인 문장은 무장 구조의 모호성이나 조사의 생략 등이 빈번하므로 의미 수준에서의 단문분할이 필요하다. 의미 영역에서 단문분할을 하면 기존의 구문 의존적인 방법들에서 발생하는 모호성을 상당수 해소할 수 있게 된다. 논문에서는 먼저 하위범주와 사전과 시소러스의 의미 정보를 이용하여 용언과 보어성분 간의 의존구조를 우선적으로 파악하고, 구문적인 정보와 기타 문법적인 지식을 사용하여 기타 성분을 의존구조에 점진적으로 포함시켜가는 이단계 단문분할 알고리즘을 제안한다. 제안된 이단계 단문분할 방법의 유용성을 보이기 위해 ETRI-KONAN의 말뭉치 중 25,000문장을 수작업으로 술어와 보어성분 간의 의존구조를 태깅한 후 본 논문에서 제안한 방법과 비교하는 실험을 수행하였으며, 이때 단문분할의 결과는 91.8%의 정확성을 보였다.

• Clinical and Experimental Pediatrics
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• 제53권5호
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• pp.616-622
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• 2010

Enterovirus 71 (EV71) has been recognized as a frequent cause of epidemics of hand-foot-and-mouth disease (HFMD) associated with severe neurological symptoms. In the spring of 2009, HFMD was epidemic in Korea. Severe cases with complication, including death, have been reported and it has become a public health issue. Most symptomatic EV71 infections commonly result in HFMD or herpangina. These clinical manifestations can be associated with neurologic syndromes frequently. Neurologic syndromes observed in EV71 include meningitis, meningoencephalomyelitis, poliomyelitis-like paralytic disease, Guillain-Barr$\acute{e}$ syndrome, transverse myelitis, cerebellar ataxia, opsoclonus-myoclonus syndrome, benign intracranial hypertension, and brainstem encephalitis. Examinations for EV 71 were performed from the stools, respiratory secretion or CSF of the children by realtime PCR. Gene analysis showed that most of them were caused by EV71 subgenotype C4a which was prevalent in China, 2008. Public health measures including personal and environmental hygiene, must to target daycare centers, kindergartens, and schools where highly susceptible children congregate. To prevent the spread of infection, preschools where transmission persists for more than 2 incubation periods, have been recommended for closure, and trigger criteria for voluntary closure was instituted. During closure, operators are to thoroughly clean the centers before they are allowed to reopen. In addition, parents are advised to ensure that their children adopt a high standard of personal hygiene and to keep the infected child at home until full recovery. Because the outbreaks occur in a cyclical pattern, surveillance system to predict next outbreaks and adequate public health measures to control need to be planned for future. Control of EV71 epidemics through surveillance and public health intervention needs to be maintained in Korea. Future research should focus on understanding of EV71 virulence, identification of the receptor(s) for EV71, development of antiviral agents and development of vaccine.

• Journal of Chest Surgery
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• 제21권3호
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• pp.510-517
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• 1988

With the ligation of a patent ductus arteriosus by Gross in 1938, surgeons first entered the field of congenital heart disease, and treatment of the patent ductus is representative of the rapid advance made in thoracic surgery in the last 40 years. We have had clinical experiences about 36 cases of this in the department of Thoracic & Cardiovascular surgery, Pusan Paik Hospital, Inje medical college from March 1891 to June 1987. And the results were summarized as follows. 1. There were 11 males, 25 females. The age range of the patients were from 8 months to 36 years with the mean age of 7.9 years. 2. The chief complaints of the patients on admission were frequent URI[50%], dyspnea on exertion[29.8%], chest pain[11.1% k 1%], growth retardation[2%], cough[2.8%], anorexia[2.8%]. But there were 11 patients[30.6%] having no subjective symptoms. 3. In auscultation, the usual continuous machinery murmur was noticed in 30 patients[83.3%], only systolic murmur in 6[16.7%]. 4. In the preoperative chest P-A views, there were noticed cardiomegaly in 20 cases, enlarged pulmonary conus and / or pulmonary plethora in 22 patients[61.1%]. 5. In the preoperative EGG findings, there were noticed pattern of LVH in 8 patients[22.2`], RVH in 2[5.6%], BVH in 4[11.5%] and normal in 19[52.89o]. 6. The size of PDA[mean] was 9.5 mm[length] and 8.8 mm[width], the range of length was from 4 to 29 mm and the range of width was from 4 to 18 mm. 7. There were noticed 6 cases which were combined with other anomalies[VSD in 2 cases, Coarctation of aorta in 2, Mitral regurgitation in 1, and AP window in 1]. 8. On operation, simple ligation of the ductus was performed in 30 cases[83.3%], division and suture-ligation in 5[13.9%]. 9. Postoperative complications were noticed in 4 cases[pneumonia in one case, wound infection or disruption in 3], but there were no mortality.

• 한국정보과학회논문지:정보통신
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• 제30권6호
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• pp.685-694
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• 2003

최근 이동성을 제공하는 시스템이 매우 빠른 속도로 보급되고 있는 추세이며 그 서비스 분야도 다양해져 무선 멀티미디어 서비스에 대한 요구가 커지고 있다. 멀티미디어 서비스는 큰 데이타 용량을 요구하며, 같은 정보를 여러 사용자들에게 보내야 하는 특징을 갖는다. 이동하는 사용자에게 이와 같은 특징을 갖는 멀티미디어 서비스를 효율적으로 제공하기 위해서는 이동성을 지원하는 멀티캐스트 기법이 필요하다. 본 논문에서는 Mobile IP 기반의 이동 네트워크 환경에서 멀티캐스트 서비스를 지원하는 기존 연구가 갖는 데이타 전송 경로의 비최적화, 빈번한 멀티캐스트 전송 트리의 재구성으로 인한 오버헤드, 서비스 단절의 문제를 해결하기 위해 이동 형태 기반의 가변 서비스 범위 멀티캐스트 기법을 제안한다. 이동 형태 기반의 가변 서비스 범위 멀티캐스트 기법은 서비스 범위를 호스트의 이동성에 따라 가변적으로 설정하고 자원 예약 기법을 사용하여 멀티캐스트 서비스를 지원한다. 다양한 실험을 통해 본 논문에서 제안된 멀티캐스트 기법을 성능 평가하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6911-6917
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• 2014

Background: Hepatocellular carcinoma is a complex and heterogeneous tumor with poor prognosis due to frequent intrahepatic spread and extrahepatic metastasis. The molecular mechanisms underlying HCC pathogenesis still remain obscure. Objectives: We aimed to investigate the abundance and the DNA binding activity of nuclear factor kappa B/p65 subunit in peripheral blood mononuclear cells from patients with HCC and to assess its prognostic significance and association with hypoxia inducible factor one alpha (HIF-$1{\alpha}$) in blood. Subjects and methods: This study was carried out on 40 patients classified equally into liver cirrhosis (group I) and HCC (group II), in addition to 20 healthy volunteers (group III). All groups were subjected to measurement of NF-${\kappa}B$/P65 subunit expression levels by real time-PCR, and DNA binding activity was evaluated by transcription factor binding immunoassay. Serum HIF-$1{\alpha}$ levels were estimated by enzyme-linked immunosorbent assay (ELISA). Significant increase of both the expression level and DNA binding activity of NF-${\kappa}B$/P65 subunit together with serum HIF-1 alpha levels was noted in HCC patients compared to liver cirrhosis and control subjects, with significant positive correlation with parameters for bad prognosis of HCC. In conclusion, NF-${\kappa}B$ signaling is activated in HCC and associated with disease prognosis and with high circulating levels of HIF-1 alpha.