• 수산해양교육연구
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• 제10권1호
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• pp.1-14
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• 1998

Transportation provides an infrastructure vital to economic growth, and it is also an integral part of production. As a port is regarded as the interface between the maritime transport and domestic transport sectors, it certainly play a key role in any economic development. Ship's delay caused by port congestion has recently has recently attracted attended with the analysis of overall operation in port. In order to analyse complicated port operation which contains large number of variable factors, queueing theory is needed to be adopted, which is applicable to a large scale transportation system in chiding ship's delay in Inchon port in relation to ship's delay problem. The overall findings are as follows ; 1. The stucture of queueing model in this port can be represented as a complex of multi-channel single-phase 2. Ship's arrival and service pattern were Poisson Input Erlangian Service. 3. The suitable formula to calculate the mean delay in this port, namely, $W_q={\frac{{\rho}}{{\lambda}(1-{\rho})}}{\frac{e{\small{N}}({\rho}{\cdot}N)}{D_{N-1}({\rho}{\cdot}N)}}$ Where, ${\lambda}$ : mean arrival rate ${\mu}$ : mean servicing rate N : number of servicing channel ${\rho}$ : utilization rate (l/Nm) $e{\small{N}}$ : the Poisson function $D_{(n-1)}$ : a function of the cumulative Poisson function 4. The utility rate is 95.0 percents in general piers, 75.39 percents in container piers, and watiting time 28.43 hours in general piers, 13.67 hours in container piers, and the length of queue is 6.17 ships in general piers, 0.93 ships in container piers, and the ship turnaround time is 107.03 hours in general piers, 51.93 hours in container piers.

• 한국콘텐츠학회논문지
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• 제19권8호
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• pp.465-472
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• 2019

지역에서 생산되는 문화행사 및 문화 콘텐츠가 다양하고 많지만 관련한 경제소비의 확대를 위한 지역정보의 유통과 확산이 부족하다. 본 연구는 지역 문화정보의 확산과 사용을 목적으로 위치기반 서비스 관점에서 지역광고주의 지역광고를 질문과 답변 형식의 지식검색 방법과 결합하고 서비스화 하였다. 접근 방법으로는 지역에 기반한 지식검색에 대한 국내외 사례와 위치기반 광고 연구를 살펴보고, 위치문답형 정보서비스의 커뮤니티 모델 그리고 지역광고의 수익 모델을 제시하였다. 이를 통해 본 연구는 지역 문화행사와 문화콘텐츠의 정보유통을 위한 문답기반 커뮤니티와 지역광고의 운영구조 모델을 설계하고 정보 서비스 시스템을 프로토타이핑 형태로 개발하였다. 사용자간의 문답 데이터의 유통을 위치정보에 확장함으로써 지역의 문화콘텐츠 정보와 사용자 접근의 수요를 지역광고의 수익모델과 결합하여 제공하는 비즈니스 서비스 모델을 제시하였다는 의의를 갖는다.

• 한국산학기술학회논문지
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• 제22권1호
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• pp.123-130
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• 2021

최근 컴퓨터 기술이 발전하면서 기계학습 분야에 관한 관심이 높아지고 있고 다양한 분야에 기계학습 이론을 적용하는 사례가 크게 증가하고 있다. 특히 금융 분야에서는 금융 상품의 미래 가치를 예측하는 것이 난제인데 80년대부터 지금까지 기술적 및 기본적 분석에 의존하고 있다. 기계학습을 이용한 미래 가치 예측 모형들은 다양한 잠재적 시장변수에 대응하기 위한 모형 설계가 무엇보다 중요하다. 따라서 본 논문은 기계학습의 하나인 강화학습 모형을 이용해 KOSPI 시장에 상장되어 있는 개별 종목들의 주가 움직임을 정량적으로 판단하여 이를 주식매매 전략에 적용한다. 강화학습 모형은 2013년 구글 딥마인드에서 제안한 DQN와 A2C 알고리즘을 이용하여 KOSPI에 상장된 14개 업종별 종목들의 과거 약 13년 동안의 시계열 주가에 기반한 데이터세트를 각각 입력 및 테스트 데이터로 사용한다. 데이터세트는 8개의 주가 관련 속성들과 시장을 대표하는 2개의 속성으로 구성하였고 취할 수 있는 행동은 매입, 매도, 유지 중 하나이다. 실험 결과 매매전략의 평균 연 환산수익률 측면에서 DQN과 A2C이 대안 알고리즘들보다 우수하였다.

• 실천공학교육논문지
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• 제12권2호
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• pp.255-264
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• 2020

데이터베이스 설계 교과목에서 팀 프로젝트는 학생들의 데이터베이스 설계 역량을 계발하기 위해 매우 중요한 과정이며, 팀 프로젝트를 원활히 수행하기 위해서는 팀원들 간의 협업과 팀워크 못지 않게 학생-교수 간의 활발한 상호작용이 매우 중요하다. 하지만 2020학년도 1학기에 갑자기 전면 비대면 수업을 하게 되면서, 데이터베이스를 구축하는 팀 프로젝트가 큰 비중을 차지하는 이 수업을 효과적으로 운영할 수 있을 지 의문이었다. 하지만 줌과 같은 실시간 화상 매체를 이용한 상호작용과 온라인 교육지원시스템(LMS)에서 지원하는 토론, 퀴즈, 질의응답 등의 기능을 적극적으로 활용하고, 온라인 발표와 상호 평가 등을 통해서 팀 프로젝트를 원활히 진행할 수 있었다. 본 논문에서는 비대면으로 공학 팀 프로젝트를 운영한 경험을 공유하고, 세 차례 실시한 설문을 기초로 이 수업의 개선 방향과 비대면 수업을 전반적으로 개선할 수 있는 여러 가지 방안을 제안하였다.

• 간호행정학회지
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• 제5권2호
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• pp.209-224
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• 1999

I have practiced this reserch for the purpose of proposition of basic data for amendment and addition of computer system after I surveyed the degree of abilities and satisfaction on the computerization in nursing\ practice. Subjects were collected from September 1 to September 30, 1998. Study subjects are 151 clinical nurses who are working at university hospital in Chonbuk area. Study instrument consists of 116 questionnaire which was developed by Kim H. K(1998). The data were analized number, mean ,t-test, ANOVA by using SPSS. The study results are as follows: 1. Most of the nurses who answered the questions were educated computerizing(96%). The abilities of computer program utilities were the most in inputting data(74%). The program nurses wanted computerizing education was wordprocess, dealing internet and statistics. 2. As for applying parts of computer system in nursing, the most nurses were Dr's order check (96%), treatment activity(91.4%), medication(89.4%), lab. test(87 .4%), transfering department(85.4%), transfering room(79.5%), diet(71.8%), discharge (70.2%), Barcord Sticker(70.2%) , reservation(62.2%) in order that were all conected order system mutually to other part. It showed that computer system was not applied for treating the original nursing work such as nursing record (13%), duty scheduling(6.0%) , nursing process(4.6%) , Q.I(1.3%), nursing research(1.3%), education(1.3%), 3. As for the benefit when computer system is applied for, the most respondence was promptness of work and convenience(90.6%) , exactness of work (82.8%), offering information exactily and efficiently(36.3%), offering good quality of nursing (6.0%) in order. 4. The degree of contentment on computerizing in nursing practice showed average 3.24%. The best marking item is that they are eager to participate in the computer education. Next, the automatic output of label and giving the number automatically is to prevent loss and mentioned items of patient registration from being changed(3.95) and to prevent mistakes possibly happening because of doctor's difficult order(3.85). 5. The problems which may happen to in nurses' utilization of computerization for the nursing practice showed average 3.18. The most problem is that the practice may stop because of the problem of computer itself(3.67), and the next, the indication of act can be imperfect(3.66) , manual training may overlap because of incomplete computerization (3.60), practical education for the computerizing is lack(3.41), and the computer literate nurses are lack(3.40) . 6. Study subject's contentment by age was significant difference(F=3.10,P=0.0119). Study subject's contentment by job posision was significant difference(F=6.001P=0.0034) I will propose the following according to the above results. The domain of original nursing practice is urgernt. Manual and indication of act should be made before long in computer obstacle. Nursing department should support the nurses so that they could receive the education needed for the nurses themselves.

• 한국전자파학회논문지
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• 제21권10호
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• pp.1169-1176
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• 2010

본 논문에서는 L1/L2 이중-밴드 GPS(Global Positioning System) 수신기용 RF 전단부를 설계하였다. 수신기는 Low IF 구조이며, 인덕터를 사용하지 않는 광대역 저잡음 증폭기(Low Noise Amplifier: LNA)와 이미지 제거를 위하여 다상 여과기(poly-phase filter)를 포함하는 quadrature 하향 변환 주파수 혼합기(quadrature down-conversion mixer) 및 전류 모드 논리(Current Mode Logic: CML) 주파수 분배기로 구성되어 있다. 저잡음 증폭기와 이미지 제거 주파수 혼합기는 높은 이득과 헤드룸 문제를 해결하기 위하여 전류 블리딩 기술을 이용하였으며, 광대역 입력 정합을 구현하기 위하여 공통 드레인 피드백을 이용하였다. $0.18{\mu}m$ CMOS 공정을 이용해 제작된 RF 전단부는 L1 밴드에서 38 dB 그리고 L2 밴드에서 41 dB의 이득을 보이며, IIP3는 L1 밴드에서 -29 dBm, L2 밴드에서는 -33 dBm이다. 입력 정합은 50 MHz에서 3 GHz까지 -10 dB 이하를 만족하며, 잡음 지수(Noise Figure: NF)는 L1 밴드에서는 3.81dB, L2 밴드에서는 3.71 dB를 보인다. 이미지 주파수 제거율은 36.5 dB이다. 설계된 RF 전단부의 칩 사이즈는 $1.2{\times}1.35mm^2$이다.

• BMB Reports
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• 제45권3호
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• pp.189-193
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• 2012

Cyst formation is a major characteristic of ADPKD and is caused by the abnormal proliferation of epithelial cells. Renal cyst formation disrupts renal function and induces diverse complications. The mechanism of cyst formation is unclear. mIMCD-3 cells were established to develop simple epithelial cell cysts in 3-D culture. We confirmed previously that Mxi1 plays a role in cyst formation in Mxi1-deficient mice. Cysts in Mxi1 transfectanted cells were showed by collagen or mebiol gels in 3-D cell culture system. Causative genes of ADPKD were measured by q RT-PCR. Herein, Mxi1 transfectants rarely formed a simple epithelial cyst and induced cell death. Overexpression of Mxi1 resulted in a decrease in the PKD1, PKD2 and c-myc mRNA relating to the pathway of cyst formation. These data indicate that Mxi1 influences cyst formation of mIMCD-3 cells in 3-D culture and that Mxi1 may control the mechanism of renal cyst formation.

• 센서학회지
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• 제17권2호
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• pp.127-132
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• 2008

The effect of $CeO_2$ as a sintering additive on the microstructure and the piezoelectric property of yPb$(Sb_{0.5}Nb_{0.5})O_3$-(1-y)Pb$(Zr_{0.52}Ti_{0.48})O_3$ ($0{\leq}y{\leq}0.1$, PSN-PZT) for a hypersonic sound speaker (HSS) application was investigated. The samples were sintered at $1250^{\circ}C$ for 2 h. The crystal structure and surface morphology of the samples were examined using XRD and FE-SEM, respectively. Study on the influence of $CeO_2$ additives on the dielectric and piezoelectric properties indicated that the $CeO_2$-added PSN-PZT system had a high piezoelectric properties. The optimized results of ${\varepsilon}_r=1209$, $K_p$=52% $d_{33}$=351(pC/N) and $Q_m$=1230.16 were obtained at 0.4 wt.% $CeO_2$-added PSN-PZT.

• 한국의료질향상학회지
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• 제2권2호
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• pp.112-129
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• 1996

Background : A small number of high cost patients usually spend a larger proportion of scarce health resources. Aged, long-term care and readmitted patients usually belong to these high cost patient group. Among others, long length of stay and readmission can be reduced by checking its cause, and these are the areas needed most of quality improvement activity. Characteristics of high cost medical users between health insurance program and medical assistance program were reviewed. Methods : The inpatient claims of health insurance and medical assistance program were analyzed. Patients were divided by 6 groups; long-term, mid-term, short-term, readmitted, cancer and aged. We defined high cost patients as those who had spent one and half million won and over per 6 months. Characteristics of high cost patients for each group were reviewed. Results : medical assistance patients used much more resources than the insured members in the average hospital cost per case but less in daily hospital cost. The former had a longer length of stay and had much heavier diseases. Major diseases of both group were cancer, diseases of circulatory system and chronic degenerative diseases. Gallstone and schizophrenia were more in the insured program. However, pulmonary tuberculosis, asthma were more common among the medical assistance patients. Early readmission before 2 weeks were 28-30% of the total readmission. Readmission rate in the malignat neoplasm and renal failure were 80% and more. Q.A program should be installed to prevent unnecessary readmissions. Conclusion : Almost 30% of early readmissions and admissions due to complications and long length of stay should be reviewed carefully to keep cost down and to enhance the quality of hospital care.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10085-10089
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• 2015

Background: The insulin-like growth factor (IGF) system comprises a group of proteins that play key roles in regulating cell growth, differentiation, and apoptosis in a variety of cellular systems. The aim of this study was to investigate the role of insulin-like growth factor binding protein 3 (IGFBP3) in hepatocellular carcinoma. Materials and Methods: Expression of IGF2, IGFBP3, and PTEN was analyzed by qRT-PCR. Lentivirus vectors were used to overexpress IGFBP3 in hepatocellular carcinoma cell (HCC) lines. The effect of IGFBP3 on proliferation was investigated by MTT and colony formation assays. Results: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells. Conclusions: Expression of IGF2, IGFBP3, and PTEN in several HCC cell lines was lower than in normal cell lines. After 5-aza-2'-deoxycytidine/trichostatin A treatment, significant demethylation of the promoter region of IGFBP3 was observed in HCC cells. Overexpression of IGFBP3 induced apoptosis and reduced colony formation in HUH7 cells.