• International Journal of Korean Welding Society
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• 제4권1호
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• pp.38-45
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• 2004

A practical method for evaluating the possibility of the occurrence of cracking in actual thick-plate T-joint weldments is presented in this study. Systematic experitrients based on the method of the design of experiment are conducted in order to investigate the crack tendency in relation to typical welding parameters such as diffusible hydrogen, restraint intensity, preheating temperature and so on. The elastic analysis using the fmite element techniques is employed to quantify the restraint intensities of the specimens. The defined restraint intensities are treated in numerical way for the sake of considering the most uncertain factor among some major factors that govern the cracking phenomena due to welding. The critical plane for judgment of the crack occurrence or crack density is presented as a function of typical welding parameters including determined restraint intensities. The results of numerical estimation by the proposed method for the experimental specimens show the usefulness as a practical tool in welding induced crack problem having extensive uncertainties.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.121-126
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• 2002

The railroad cars or the commercial vehicles are generally manufactured by the spot welding. Among various kinds of spot welded lap joints, multi-lap joints are one of popular joints in manufacturing their body structures. But, fatigue strength of these joints are lower than that of base metal due to high stress concentration at the nugget edge of the spot weld and are known to considerably be influenced by welding conditions as well as the mechanical and geometrical factors. Thus, it is necessary to establish a reasonable and systematic fatigue design criterion for spot welded multi-lap joints. In this paper, the $\Delta$P-N$_{f}$ curves has been rearranged in the $\Delta$$\sigma$-N$_{f}$ relation with the maximum stress at the nugget edge of spot welded multi-lap joints subjected to tensile shear load. Consequently, the fatigue data were evaluated in terms of fracture mechanics by plotting on the $\Delta$OP-N$_{f}$ curves. From the results obtained, both of them have been revealed to be applicable to fatigue design of spot welded multi-lap joints. However, the fracture mechanical approach is found to be more effective than the maximum stress approach in the range on N$_{f}$$\geq$2x10$^{5}$ . .

• 한국통신학회논문지
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• 제35권5B호
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• pp.777-784
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• 2010

현대의 정보화 사회에서는 정보기술이 기업과 공공기관에 도입되면서 정보기술 전반을 관리해야 한다는 필요성이 대두되었고, 비즈니스 목표와 IT의 연계 필요성이 증대되고 함께 IT투자의 중복을 방지하고 ROI를 추구하는 조직들이 늘어났다. 이에 여러 선진 기업들이 IT 거버넌스라는 개념을 제창하였다. IT 거버넌스는 기업의 비즈니스와 IT에 영향을 미치는 구조적 결정인자들의 구조 및 동적양상을 나타내며, 비즈니스와 IT 관련 사내외 위원회 및 부서, 그리고 그들의 활동범위 및 연관관계를 나타내는 프레임워크, 조직도 및 프로세스 구성으로 표현이 된다. 이러한 외부적인 요인과 맞물려 현재 우리 군의 국방 비전과 목표를 달성하기 위한 국방 IT 거버넌스의 재확립은 필수적인 사항이 되었다. 본 논문에서는 국방 IT 거버넌스의 프레임워크를 구축하기 위한 핵심 추진전략에 대해서 기술하였다. 이러한 주장에 뒷받침하기 위해서 IT 거버넌스의 전반적인 내용을 기술하고 국내 외와 해외의 군 사례를 분석하여 보고 국방 IT 거버넌스의 프레임워크 구축을 위한 핵심 추진전략을 연구하였다.

• 한국물환경학회지
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• 제32권1호
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• pp.52-59
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• 2016

This study investigated the occurrences and succession patterns of harmful cyanobacteria, as well as environmental factors, during a 3-year period (September 2012 to August 2015) in the upper region of the Nakdong River around Sangju weir. A total of 27 cyanobacterial taxa were observed in this study, and classified into 26 species and 1 variety belonging to 11 genera, 5 families, and 3 orders. Cell density ranged from 24 to 42,001 cells/ml, with a geometric mean of 33 cells/ml, during the survey period. The dominant orders differed depending on the survey year; order Oscillatoriales in 2013, Chroococcales in 2014 and Nostocales in 2015. An Aphanizomenon bloom occurred in June 2015 at which time the highest cell density of 36,873 cells/ml was detected in the upper region of the Nakdong River, where as the Aphanizomenon spp. cell density (190-1,704 cells/ml) had been low prior to that time. An Aphanizomenon bloom also occurred at around the same time downstream in the Young River, a major inflow branch of the Nakdong River. The Aphanizomenon cell density along the Nakdong River increased markedly after joining of the YoungRiver, indicating that the Aphanizomenon bloom in the YoungRiver caused a bloom in the Nakdong River. Meteorological and environmental parameters, such as very low precipitation, higher water temperature, pH, and TP concentration, and lower TN/TP ratio, in May and June of 2015 than in 2013 and 2014 exerted marked effects on the Aphanizomenon bloom in June 2015 in the Young River.

• 간호행정학회지
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• 제5권1호
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• pp.137-148
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• 1999

The study was attempted to survey the pay and job satisfaction of clinical nurses in some hospitals. The period was Jan 6th through Jan 27th. 1997 and the subjects were 277 nurses working in 5 hospitals in Pusan city. This study was based on questionnaires which focused on the pay and job satis faction of the nurses. The following instruments were used for collecting the data: PSQ. JDI and MSQ on the scale of 1 being lowest to 5 being highest satisfaction. The analysis of collected data was executed by using SPSS/PC+. The results were as follows: 1. The main age level was 26-30 and the portion was 44.4%. The Mean of the monyhly pay was 930 ${\pm}$130 thousand won. 2. The average point of pay satisfaction was 2.17${\pm}$.61. 3. The average point of job satisfaction was 2.87 ${\pm}$.66. 4. The factors which affect the pay satisfaction were 'the size of hospital'. 'the joining of labor unions' and 'the amount of pay' . 5. The factors which affect the job satisfaction were 'the size of hospital'. 'the job rank' and 'the amount of In conclusion, nurses are not satisfied with their job and pay levels because of the size of the hospital and the amount of pay, In order to solve the problem of turnover. medium-sized hospitals need to standardize and modify the levels of pay, the structure and the system according to standards well established by large-sized hospitals.

• 한국의상디자인학회지
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• 제21권4호
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• pp.27-42
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• 2019

This paper tried a detailed approach to identify the correlation among basic elements that influenced the change of forms of the Po. To this end, the subjects were limited to the clothing from the 15th to the 18th century, which was found in the tombs of the period of Pyeonbokpo. The total number of excavated artifacts measured directly is 6 and other correctly described excavated artifacts for a total of 54 items. Per period and element, the types of collars and Seop were presented by classifying collars in 4 types, and Seop in 3 types. On the basis of the classification, the relics selected in this paper were analyzed considering the appearance, period, and rate per type of each element. The type and the change of forms of each element per period, with the focus on the appearance, were identified and the factors influencing the change of forms per element and the correlation between such factors were investigated. The representative type in the first period included dual collars, dual Seop and the representative type in the second period was characterized by a shawl collar and a dual Seop joining the pieces. The representative type in the third period was characterized by round collars and a short Seop. The elements determining the forms of Po, including collars and Seop, had a correlation to the lapse of time and had been systematically influencing each other. Furthermore, the overall change of form was caused due to the social functions as well as the supplementary function of keeping balance among the elements and accordingly, the change of forms was think characterized per period.

• 한국직업건강간호학회지
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• 제18권1호
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• pp.98-105
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• 2009

Purpose: This study was to analyze the current preventive measures on alcohol-involved accident and the factors that affect such preventive measures in the construction industry. Method: The survey was administered to examine how the preventive measures on alcohol-involved accident were executed using the data of '2005 Occupational Safety and Health Survey' conducted in 2005 by the Occupational Safety and Health Research Institute. For this study, we analyzed 944 work places in the construction industry. Result: The preventive measures on alcohol-involved accident were being executed in 62.1% of construction companies. As for the number of actual preventive measures on alcohol-involved accident, work places in Jeolla-do executed 2.63 times more frequently than those in Chungcheong-do, and work places with the Occupational Safety and Health Conference executed 2.22 times more frequently than those without such a measure. Conclusion: Joining the Occupational Safety and Health Conference was to be one of the most influential ways of preventive measures on alcohol-involved accident in the construction industry. Accordingly, if workers and employers look for active measures and administer them through the Occupational Safety and Health Conference, it will reduce alcohol-involved accident in the construction industry and contribute to the better preventive measures on alcohol-involved accident in the construction and other industries.

• 생명과학회지
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• 제27권12호
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• pp.1515-1522
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• 2017

대부분의 사람은 오래 살기를 원한다. 고대 중국과 한국의 신화에 동방삭이라는 인물이 일만 팔천 년을 살았다고 전해진다. 현실 세계에서는 WHO의 보고에 따르면 사람의 평균수명이 1960년대에 50세에서 2016년에는 75-85세로 25~35세가 늘었다. 두 마리의 실험 동물을 외과적 수술을 통해 병렬로 결합하여 두 동물의 순환계(혈액)이 서로 연결되게 하는 개체병렬결합(parabiosis) 실험모델이 1860년도에 개발된 이래 이 방법은 in vivo에서 한 개체가 다른 개체에게 어떤 영향을 미칠 수 있는가에 대한 연구를 위한 강력한 실험 모델이 되어 왔다. 여러 가지 실험조건의 연구 중에서도 개체병렬결합모델은 노화의 진행을 역행하는 현상을 조사하는 연구에서 필수적인 모델이 되고 있다. 본 총설에서는 개체병렬결합모델의 탄생과 이로 인한 중요한 발견을 시간대에 따라 소개하며, 아직은 확정적이지는 않지만 젊은 쥐와 늙은 쥐의 순환계를 연결시킨 이 모델을 사용하여 노화의 진행을 역행시킬 수 있는 "젊음의 인자"인 growth differentiation factor 11 (GDF11)을 발견한 연구 결과에 대해 서술하고자 한다. 지금까지 밝혀지고 있는 여러 조건에서의 연구결과가 증명하였듯이 개체병렬결합모델은 향후 다양한 생리적 현상을 규명하는데 더욱 중요한 실험모델이 될 것으로 예상된다.

• 한국건설관리학회논문집
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• 제14권5호
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• pp.55-64
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• 2013

의료시설은 일반건축물 보다 공사의 복잡성이 높고, 정부규제가 엄격하여 공사 단계에서의 설계변경과 하자보수들이 많이 발생한다. 본 연구에서는 의료시설의 중점 관리공사와 요인들을 도출하고 분석하여, 설계단계와 공사단계에서 관리가 잘 되지 않는 공사들을 분석하였다. 그리고 2013년 현재 진행되고 있는 의료시설 공사 관리자들의 인식을 조사하여, 개선 가능성이 큰 공사를 도출하였다. 먼저, 중점 관리요인들을 건축과 설비, 그리고 전기의 세 분야로 분류하여 도출하였다. 다음으로, 1) 공사 진행단계에서 설계변경이 많이 발생하고, 2) 하자보수들이 많이 발생하고 소요비용이 큰 중점 관리공사와 요인들을 분석하였다. 마지막으로, 진행 중인 의료시설 공사 관리자들이 중요하게 생각하지 않는 공사를 조사하였다. 설계변경과 하자보수가 많지만, 중요하게 생각하고 있지 않다면 개선 가능성이 클 것이기 때문이다. 설계단계에서는 마감공사, 벽체공사, 창호공사, 사무 자동화 및 통신기능 공사, 조명공사, 그리고 공사 관리단계에서는 폐기물 공사, 사무자동화 통신기능, 창호공사, 오염관리, 배관공사로 분석되었다. 본 연구의 결과인 설계변경과 하자보수가 많은 공사, 그리고 개선 가능성이 큰 공사의 관리를 실시 설계단계와 공사 관리단계에서부터 집중 관리하여야 할 것이다.

• Journal of Welding and Joining
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• 제33권5호
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• pp.35-40
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• 2015

Characterization of microstructures and mechanical properties of 83mm thickness EH36-TM welds produced by the combined flux cored arc (FCA) and electro gas (EG) welding processes has been studied with the two different groove conditions, single-V (SV) and double-V (DV) bevels. The welding consumables used for FCA and EG welding processes were ASME/AWS A5.29 (E81T1-K2) and A5.26 (EG72T), respectively. Experimental results showed that all the mechanical properties of welds such as tensile property, CVN toughness and Vickers hardness met IACS requirements. The tensile strength of EG welded plates were reduced by approximately 4% (DV: 3.8%, SV: 4.2%) compared to the base metal. The hardness value of SV-beveled weld metal was slightly lower than that of DV-beveled one. There were no significant differences as per welding groove conditions except for the weld metal. In addition, at the fusion line, the toughness of SV condition was 20J lower and the weld metal was 40J lower than DV condition, respectively. On the basis of microstructural analysis, grain boundary ferrite (GBF) structures for SV condition were 2 times higher volume fraction than for DV condition and their packet sizes were coarsened to almost double. It was thus suggested that the GBF volume fractions and packet sizes in the weld metal of EH36-TM steel plates are the most important factors affecting the mechanical properties of the combined FCA and EG welded joint. Nevertheless, all the results of welds with both DV and SV conditions were found to be excellent.