• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.465-472
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• 2016

Principal Component Analysis (PCA) is useful statistical technique for finding patterns in data, and expressing the data in such a way as to highlight their similarities and differences. In this paper, 1417 marine casualties occurred in Korean littoral sea in recent 5 years, were examined by the PCA. The main results obtained were as follows : 1. Most of marine casualties resulted from the human factors such as careless operation and insufficient engine maintenance. 2. Collision and standing mainly resulted from steering room-related human factors such as careless guard, inadequate ship-handling, however engine damage and fire explosion mainly resulted from engine room-related human factor such as bad handling of engine system. 3. No. 1 principal component represents accident frequency, No. 2 principal component represents the cause and No. 3 principal component represents the pattern of marine casualties, respectively.

• Proceedings of the Korea Society for Simulation Conference
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• 1992.10a
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• pp.9-9
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• 1992

시뮬레이션(simulation)은 실 시스템(real system)의 효과적이고 효율적인 운영을 도모하기 위하여 실 시스템의 동작을 이해하고 분석, 예측, 평가하는 과학적인 문제해결 접근방법이다. 시뮬레이션 수행단계는 실 시스템의 행위를 정확히 반영하도록 타당한 모델을 구축하는 모델링 단계와 모델에 의도하는 명령어들을 컴퓨터 프로그램으로 작성하는 구현단계로 나누어진다. 시뮬레이션 모델은 시간, 상태, 확률변수, 상호규칙 등의 여러 관점에 따라 다양하게 존재하는데, DEVS(Descrete EVent system Specification) 모델은 연속적인 시간상에서 이산적으로 발생하는 사건에 따라 시스템의 상태를 분석할 수 있고 모델링 및 시뮬레이션 방법론의 형식화를 위한 견고한 이론적 기반을 제공하고 있다. 또한, DEVS 모델은 모듈적, 계층적 특성을 제공하고 집합론에 근거한 수학적 형식구조를 제공하여 실 시스템에 대한 체계적인 분석과정을 수행하게 되어 보다 현실적인 모델링을 가능하게 한다. 그러나 타당하지 못한 DEVS 모델이 구축되면 시뮬레이션을 통한 분석결과의 신뢰성이 떨어져 아무런 효과가 없고 경제적인 손실만이 따른다. DEVS 모델에 대한 기존의 타당성 검사가 많은 시간과 노력이 요구되고, 반복적인 DEVS 모델링 과정으로 인한 전문적이고 경험적인 지식을 요구한다. 또한, 모델설계자에 의해 설정된 실험 프레임하에서 DEVS 모델의 구성요소에 속하는 상태전이함수, 시간진행함수 및 출력함수에 대하여 commutative 성질의 보전성 검사가 어렵다는 문제점을 가지고 있다. 본 연구에서는 이와 같은 문제점을 해결하기 위하여, DEVS 모델에 대한 타당성 검사를 SPN(Stochastic Petri Net) 모델로 변환하여 SPN 모델을 이용하는 간단하고 효과적인 타당성 검사 방법을 제안한다. 먼저, DEVs 모델에 대한 개념과 기존의 DEVS 모델에 대한 타당성 검사 방법을 고찰하고 그 문제점에 대하여 자세히 설명한다. DEVS 모델의 타당성 검사에 이용하는 SPN 모델에 대한 개념과 DEVS 모델과 행위적으로 동등한 SNP 모델로 변환을 위한 관점을 제조명하다. 동일한 관점에서 두 모델의 상태표현이 같도록 DEVS 모델이 SPN 모델로 표현됨을 보이는 변환이론을 제시하고 변환이론을 바탕으로 모델 변환과정을 제시한다. 모델 변환이론과 변환고정을 기본으로 타당성 검사를 위한 새로운 동질함수(homogeneous function)를 정의하고 이와 함께 SPN 모델의 특성을 이용하여 DEVS 모델에 대한 타당성 검사 방법을 새롭게 제안한다.

• Journal of Breast Disease
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• v.6 no.2
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• pp.35-38
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• 2018

Purpose: The eighth American Joint Committee on Cancer staging system for breast cancer was recently published to more accurately predict the prognosis by adding biomarkers such as estrogen receptors, progesterone receptors, and human epidermal growth factor receptor 2. However, this system is very complicated and difficult to use by clinicians. The authors developed a program to aid in setting up the staging system and confirmed its usefulness by applying it to theoretical combinations and actual clinical data. Methods: The program was developed using the Microsoft Excel Macro. It was used for the anatomic, clinical and pathological prognostic staging of 588 theoretical combinations. The stages were also calculated the stages using 840 patients with breast cancer without carcinoma in situ or distant metastasis who did not undergo preoperative chemotherapy. Results: The anatomic, clinical and pathological prognostic stages were identical in 240 out of 588 theoretical combinations. In the actual patients' data, stages IB and IIIB were more frequent in clinical and pathological prognostic stages than in the anatomic stage. The anatomic stage was similar to the clinical prognostic stage in 58.2% and to the pathological prognostic stage in 61.9% of patients. Oncotype DX changed the pathological prognostic stage in 2.1% of patients. Conclusion: We developed a program for the new American Joint Committee on Cancer staging system that will be useful for clinical prognostic prediction and large survival data analysis.

• Journal of Convergence for Information Technology
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• v.9 no.8
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• pp.53-62
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• 2019

This study is a descriptive study to investigate the relationship between verbal violence type, emotional response and coping in the operating room nurse. The subjects of the study were 400 nurses working in 20 general hospitals and 372 nurses in the operating room. As a result of the analysis, it was found that the perpetrators of the verbal violence experienced by the subject were physicians, direct supervisors, and more than half of the subjects were considering the transition. The most frequent cases of language violence were when the equipment was inoperable or not used during surgery, There were significant differences in verbal violence experience according to marriage, clinical career, and work style. Language violence emotional response showed significant difference with gender, position and coping, age, academic background, clinical career, and position. There was a significant correlation between experience of verbal violence and emotional response, emotional response and coping. Therefore, the results of this study will contribute to the development of coping strategies and prevention education programs.

• Journal of the Korean Geotechnical Society
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• v.24 no.1
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• pp.81-89
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• 2008

The purpose of this study is to develop a new technique to quickly assess the quantitative stability of a tunnel by using measured displacement at the tunnel construction site. To achieve this purpose, in this study, a critical strain concept was introduced for the first time and applied to an assessment of a tunnel under construction. The new technique calculates numerically the strains of the surrounding ground by using displacements measured during tunnel excavation. The techniques considering the relative displacement, shotcrete, and anisotropic characteristics of ground were newly introduced after reinvestigating the existing analysis technique. In addition, an analysis module was developed based on the proposed analysis technique in this study, and the applicability of the developed module was verified. To verify the module, first of all, the calculated excavation displacements of a cylindrical tunnel by analytic method and commercial programs (Pentagon-3D, Flac-2D) were compared for the confirmation of applicability of commercial programs. Then, the calculated excavation displacements under the same initial condition, both with and without a shotcrete lining, by two commercial programs were compared. finally, we assess the load condition and material properties of in-situ ground by inputting tunnel excavation displacement, which was calculated by a commercial program, into the developed analysis module (FAST-Ver. 1.2, feedback Analysis System for Tunneling), and checked whether the assessed results conform to the originally assumed values.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.1
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• pp.87-102
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• 2023

The purpose of this study is to propose an analytical framework for the essential contents that must be included in a climate change education program for elementary school students based on community issues, which can be used by citizen instructors in the community. To develop the analytical framework, 24 climate environmental education specialists were consulted seven times. The content validity of the final analysis framework was statistically verified using I-CVI and S-CVI coefficients, and the reliability of the expert panel was verified using Fleiss' Kappa coefficient. The final analysis framework consists of three analytical areas (program objectives, program content, program evaluation), seven analysis items, seven analysis indicators, and detailed explanations of the analysis indicators. In particular, by adding detailed explanations for the analysis indicators, the content validity and reliability were increased, and the objective nature of the analysis framework was firmly established. It is expected that the proposed analytical framework for a community-based climate change education program for elementary school students in this study will contribute to the systematic development of the program by citizen instructors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.332-339
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• 2016

This study aimed to investigate the awareness and performance of safety in operating room nurses. There were 161 operating room nurses from eight general hospitals included for analysis in this study. The data were analyzed with t-test, one-way ANOVA, correlation analysis, and Scheffe's test. The results show that their perception of patient safety was 3.33 out of a total of 5 points. Moreover, the score of safety management activity for patients in the operating room was 4.28 out of 5 points. As the perception of patient safety in operating room nurses was significantly correlated with their safety management activities, nurses with higher awareness of patient safety were found to have higher degree of performance of safety management activities. In conclusion, to improve safety management activities, open discussion about patient safety should be encouraged and periodic education regarding patient safety should be implemented for operating room nurses to increase the perception of patient safety.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.239-242
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• 2002

코드사 재봉기는 커튼, 침장류와 같은 제품에 입체구조의 무의를 발현시키기 위하여 30,000 ~50,000d 굵기의 실을 사용하여 직물표면에 입체 무의를 만드는 특수 재봉기이다. 이 재봉기는 작업자가 방향 전환 핸들을 이용하여 무의를 직접 만들어야 하는 수동방식이기 때문에 숙련공의 의존도가 높다. 그래서 숙련공의 의존도를 낮추고 제품의 질, 균일성, 생산성을 향상시키기 위하여 자동화가 절실히 요구되어 왔다[1]. (중략)

• Journal of the KSME
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• v.25 no.1
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• pp.32-38
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• 1985

지금까지의 계산된 직접 분사식 디이젤기관에서의 분무유동 현상은 실린더내에서의 공기유동과 공기밀도의 온도에 대한 변화를 고려하지 않은 경우이다. 디이젤 연소의 모델링을 위한 몇가지 단계, 즉 (1) 연소실내에서 공기유동을 무시한 경우의 분무유동 특성 (2) 공기유동 (swirl, squish, turbulence)을 고려한 경우에서의 분무유동 특성 (3) 연소실내에서의 분무제트와 주위 기체사이에의 열 및 질량의 이동현상 (4) 연소실 벽면과 연소가스 사이에의 열역학적 관계 의 4가지 단계중 제 1단계에 해당하는 모델로써 보다 완벽한 가정과 정확한 입력 데이터를 이용하면 좋은 예측결과를 나타낼 수 있는 자료가 될 수 있겠으며 공기유동을 고려한 경우의 분무유동 또한 프로그램이 거의 완성단계에 있으므로 가까운 시일내에 이용할 수 있으리라 믿는다.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.10a
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• pp.338-343
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• 1998

본 논문에서는 클라이언트/서버 형태로 컨베이어 시스템을 원격으로 제어하는 방법을 제시하고 있다. 이러한 시스템의 구성은 근거리통신망으로 원격지에 연결된 컨베이어 시스템을 상황실에서 제어하는 형태를 가진다. 서버 시스템에서는 컨베이어 시스템을 통과하는 생산품 내역에 대한 데이터 베이스를 저장, 유지, 관리한다. 또한 컨베이어 시스템을 제어하는 프로그램을 수행시킨다. 컨베이어 시스템은 승용차 조립라인을 모델링한 시스템으로 구성되어 있다.