• 디지털융복합연구
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• 제10권1호
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• pp.357-364
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• 2012

소프트웨어의 폐쇄적 지적재산권에 대한 저항으로 자유소프트웨어 운동이 추진되어 라이선스에서 제시한 사항을 이행하는 사람은 누구나 자유롭게 소프트웨어를 이용하고 개작할 수도 있는 오픈소스 소프트웨어가 널리 이용되고 있다. 오픈소스소프트웨어는 제품의 개발시간과 비용을 줄일 수 있고 이를 사용하는 많은 사람들의 검증을 거치게 되므로 개선되고 발전되어 간다. 그러나 이러한 장점과 더불어 무분별한 사용으로 분쟁의 발생위험도 높다. 이에 본 연구에서는 오픈소스 소프트웨어 분쟁 사례를 분석하여 오픈소스소프트웨어의 저작권 침해를 방지하고 적법하게 오픈소스소프트웨어를 이용할 수 있는 사용자 환경을 제시하고자 한다.

• 교육시설
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• 제11권1호
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• pp.5-14
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• 2004

Since 1990s in Korea, elementary school classrooms have been designed toward open education system in pursuit of variety of educational purpose. Also, the architectural designs of schools have been acomplished for individual school not based on the standard design code. The present paper aims to investigate the acoustic environment of existing classrooms and to compare the sound insulation capacity between the ordinary classrooms and the newly built classrooms for open education. The current acoustical situation of elementary classrooms was analyzed using field measurements and questionnaire survey. In order to this, Three elementary schools were selected which were built in 1978, 1996 and 2000 respectively. Room acoustical parameters including Reverberation time(RT), Definition(D50), Speech Intelligibility(RASTI), Transmission loss(TL) and STC were measured in a classroom in each elementary school classroom. Each measurement was undertaken with the windows and doors being open or closed. As the result, it was found that the transmission loss between rooms in open classrooms is, $5{\sim}6dB$ in average, inferior than the ordinary classrooms. The RASTI of 0.70 was measured in newly built classrooms which is better than old classrooms(0.70) and open classrooms(0.73). This was shown as same in the speech definition measurements. This results from the condition of sealing and airtightness of classrooms and floor materials. The results denote that open classrooms have poor acoustic condition in sound insulation and speech intelligibility.

• 한국통신학회논문지
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• 제41권12호
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• pp.1801-1810
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• 2016

본 논문에서는 최근 많은 관심과 집중을 받고 있는 SDN 분야 오픈 소스 프레임워크인 오픈데이라이트 컨트롤러를 중심으로 컨트롤러 클러스터 구조 및 동작방식에 대하여 분석한다. 오픈데이라이트 컨트롤러 클러스터에서는 컨트롤러 간 데이터 스토어의 동기화를 위하여 분산 샤드 구조 및 샤드 리더 선정을 위한 Raft 알고리즘을 적용하고 있다. 성능 분석에서는 컨트롤러 클러스터 크기, 샤드 역할, 샤드 정책에 따른 CRUD, Routed RPC 지연시간 및 리더 재선정 지연시간 등을 분석함으로써, 오픈데이라이트 컨트롤러 클러스터 운영 시의 최적 운영 방안을 논의한다.

• 한국추진공학회지
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• 제22권6호
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• pp.28-36
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• 2018

기체 탄화수소 연료를 사용하는 덤프 연소기의 연소불안정에 개루프 제어를 적용하는 연구를 수행하였다. 연료들의 특성화학시간이 유사한 연소조건에서 음향 발생기를 이용하여 제어 출력과 주파수를 변화시켰다. 연소불안정 주파수와 동일한 주파수의 개루프 제어에서는 음향 발생기의 출력이 제어성능에 영향을 주었다. 연소불안정 주파수와 다른 주파수의 개루프 제어결과로부터 개루프 제어주파수는 연소불안정 주파수와 유사하게 설정하는 것이 효과적임을 알 수 있었다.

• International Journal of Computer Science & Network Security
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• 제21권3호
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• pp.145-152
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• 2021

In the Recent times, various technological enhancements in the field of artificial intelligence and big data has been noticed. This advancement coupled with the evolution of the 5G communication and Internet of Things technologies, has helped in the development in the domain of smart mine construction. The development of unmanned vehicles with enhanced and smart scheduling system for open-pit mine transportation is one such much needed application. Traditional open-pit mining systems, which often cause vehicle delays and congestion, are controlled by human authority. The number of sensors has been used to operate unmanned cars in an open-pit mine. The sensors haves been used to prove the real-time data in large quantity. Using this data, we analyses and create an improved transportation scheduling mechanism so as to optimize the paths for the vehicles. Considering the huge amount the data received and aggregated through various sensors or sources like, the GPS data of the unmanned vehicle, the equipment information, an intelligent, and multi-target, open-pit mine unmanned vehicle schedules model was developed. It is also matched with real open-pit mine product to reduce transport costs, overall unmanned vehicle wait times and fluctuation in ore quality. To resolve the issue of scheduling the transportation, we prefer to use algorithms based on artificial intelligence. To improve the convergence, distribution, and diversity of the classic, rapidly non-dominated genetic trial algorithm, to solve limited high-dimensional multi-objective problems, we propose a decomposition-based restricted genetic algorithm for dominance (DBCDP-NSGA-II).

• Journal of Gastric Cancer
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• 제13권1호
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• pp.51-57
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• 2013

Purpose: Additional gastrectomy is needed after endoscopic resection for early gastric cancer when pathology confirms any possibility of lymph node metastasis or margin involvement. No studies depicted the optimal type of surgery to apply in these patients. We compared the short-term and long-term outcomes of laparoscopic gastrectomy with those of open gastrectomy after endoscopic resection to identify the optimal type of surgery. Materials and Methods: From 2003 to 2010, 110 consecutive patients who underwent gastrectomy with lymphadenectomy either by laparoscopic (n=74) or by open (n=36) for gastric cancer after endoscopic resection were retrospectively analyzed. Postoperative and oncological outcomes were compared according to types of surgical approach. Results: Clinicopathological characteristics were comparable between the two groups. Laparoscopic group showed significantly shorter time to gas passing and soft diet and hospital day than open group while operation time and rate of postoperative complications were comparable between the two groups. All specimens had negative margins regardless of types of approach. Mean number of retrieved lymph nodes did not differ significantly between the two groups. During the median follow-up of 47 months, there were no statistical differences in recurrence rate (1.4% for laparoscopic and 5.6% for open, P=0.25) and in overall (P=0.22) and disease-free survival (P=0.19) between the two groups. Type of approach was not an independent risk factor for recurrence and survival. Conclusions: Laparoscopic gastrectomy after endoscopic resection showed comparable oncologic outcomes to open approach while maintaining benefits of minimally invasive surgery. Thus, laparoscopic gastrectomy can be a treatment of choice for patients previously treated by endoscopic resection.

• Journal of Gastric Cancer
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• 제13권3호
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• pp.136-148
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• 2013

Purpose: To define the role of robotic gastrectomy for the treatment of gastric cancer, the present systematic review with meta-analysis was performed. Materials and Methods: A comprehensive search up to July 2012 was conducted on PubMed, EMBASE, and the Cochrane Library. All eligible studies comparing robotic gastrectomy versus laparoscopic gastrectomy or open gastrectomy were included. Results: Included in our meta-analysis were seven studies of 1,967 patients that compared robotic (n=404) with open (n=718) or laparoscopic (n=845) gastrectomy. In the complete analysis, a shorter hospital stay was noted with robotic gastrectomy than with open gastrectomy (weighted mean difference: -2.92, 95% confidence interval: -4.94 to -0.89, P=0.005). Additionally, there was a significant reduction in intraoperative blood loss with robotic gastrectomy compared with laparoscopic gastrectomy (weighted mean difference: -35.53, 95% confidence interval: -66.98 to -4.09, P=0.03). These advantages were at the price of a significantly prolonged operative time for both robotic gastrectomy versus laparoscopic gastrectomy (weighted mean difference: 63.70, 95% confidence interval: 44.22 to 83.17, P<0.00001) and robotic gastrectomy versus open gastrectomy (weighted mean difference: 95.83, 95% confidence interval: 54.48 to 137.18, P<0.00001). Analysis of the number of lymph nodes retrieved and overall complication rates revealed that these outcomes did not differ significantly between the groups. Conclusions: Robotic gastrectomy for gastric cancer reduces intraoperative blood loss and the postoperative hospital length of stay compared with laparoscopic gastrectomy and open gastrectomy at a cost of a longer operating time. Robotic gastrectomy also provides an oncologically adequate lymphadenectomy. Additional high-quality prospective studies are recommended to better evaluate both short and long-term outcomes.

• 공업화학
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• 제10권4호
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• pp.531-536
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• 1999

누출시험 장치를 이용하여 미량 물 누출 실험을 수행하였다. 2.25Cr-1Mo 시편의 누출경로는 나트륨-물 반응 생성물에 의해 plugging되는 경우가 발생하였으나, 대부분 re-open상태를 나타내었다. 또한 누출 경로가 완전 re-open된 후 나트륨 부위에서 시편의 self-wastage pattern은 온도에 영향을 받지 않음을 알 수 있었으며, 누출경로가 re-open 되면서 나타나는 defected 크기는 대략 5 mm 이내임을 알 수 있었다. 누출 경로가 완전 re-open 되는데 걸리는 시간은나트륨 온도가 높을수록 짧게 나타났으며, 평균적으로 $450^{\circ}C$에서 143분, $475^{\circ}C$의 경우 40.7분, $510^{\circ}C$의 경우 34.7분을 나타내었다.

• 문화기술의 융합
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• 제4권1호
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• pp.291-297
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• 2018

본 논문에서는 무대에서의 방송용 카메라를 위한 자동 객체추적 시스템을 구현한다. 객체추적을 위해서 Open-CV 기반의 파이썬 프로그램을 탑재한 PC, 라즈베리파이 3, 모바일 장치를 사용한다. 영상 객체추적 방법으로는 mean-shift, CAMshift, GMM을 이용한 백그라운드 모델링, SURF를 이용한 템플레이트 기반 추적, CMT, TLD 등의 방법들이 있다. CAMshift 알고리즘은 고속 및 성능의 강인함으로 실시간 추적에 효율적이지만, 본 논문에서는 CMT 알고리즘을 이용한 방송용 카메라의 영상 객체추적 시스템을 구현한다. 이것은 정적 및 적응형 일치성 때문에 최적의 영상 추적 방법이다. 제안된 시스템은 무대에서의 실시간 연속적인 객체추적을 위한 효율적이고 강인한 영상 추적 시스템에 잘 응용될 수 있다.

• Journal of Chest Surgery
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• 제14권1호
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• pp.1-8
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• 1981

Alterations in serum enzymes were studied in twenty-five patients who underwent open heart surgery in N.M.C. during the period from June 1979, to Feb. 1980. There were fifteen congenital and ten acquired heart diseases. In all patients, Rygg-Kyvsgaard five head roller pump and Polystan bubble oxygenator were used and serial determination of total level of Creatine phosphokinase [CPK], Lactic dehydrogenase [LDH], Glutamic oxaloacetic transaminase [SGOT] were made preoperatively, operation day [just after aortic clamp release, 2 hrs later, 4 hrs later, 6 hrs later], and postoperative days up to 5th day. Immediate postoperative clinical courses were also evaluated. Twenty-five patients were divided into two groups: Group A[13] was cardiopulmonary bypass time more than 95 minutes and aortic clamp time more than 45 minutes. Group B[12] was cardiopulmonary bypass time less than 95 minutes and aortic clamp time less than 45 minutes. The peak levels of SGOT, LDH in Group A were more significantly elevated than Group B [P<0.05]. But peak levels of CPK were not significant between two groups. In the view of clinical evaluation, poor clinical courses were more frequent in Group A [54%] than Group B[8%].