• 한국건축시공학회지
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• 제3권1호
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• pp.107-114
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• 2003

This study aims to find methods that prevents aging of buildings paint coating and that limits defects in construction. Defects in painting can occur in four stages: pure paint, during painting, after the paint coating has dried, and after some period of time has passed after coating. Paint may become bad due to precipitation of pigments, formation of membranes, and seeding during manufacturing. Therefore, it is important that the paint is well mixed and kept airtight at a cool, dark place. Indents, paint brush strokes, orange peel, separation of colors, and paint running and spreading during the paint work process can be prevented by using high quality materials and applying a high-level of construction method. After the paint coating has dried, boiling, yellowing, poor drying, poor bonding, and/or glen deficiency may occur. These are influenced by the levels of cleanness of the dried product, drying temperature and hydration. Then, when the coating has been left dried for some period of time, cracking, peeling, scaling, swelling, discoloring, and/or rusting may develop due to the ultraviolet and contaminants in the air. Since these defects occur due to inappropriate construction schedule and/or hot and humid condition, one must use weatherproof materials. Furthermore, poor paint color may be caused by contamination in the sample plate, discoloration, and/or discrepancies in colors which are due to material differences, level of glossiness, degree of dispersion, dual color property of metallic colors, precipitation of pigments, etc. One should achieve reduction in construction cost and effectiveness in paint work by limiting contaminations in the construction site and strictly observing to construction regulations.

• 한국안전학회지
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• 제20권3호
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• pp.188-196
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• 2005

Accident reports from 1991 to 2000 of a steel company were used to analyze which factors induce industrial accidents. The subjects were 8,311 blue-collar workers, who sustained 114 occupational injuries and work on a continuous full-day 3-team 3-shift system of backward rotation(mornings to afternoons to nights). With respect to marital status, the occupational injury rate(OIR) on the married workers was significantly higher compared to unmarried workers. With respect to no, the OIR of those in their early 20s was significantly higher when compared to other age groups. The OIR of highly educated workers showed a reduction when compared with lower educated workers. The OIR of shift workers were significantly higher compared with the daytime workers. The OIR of type of work decreased across the steel manufacturing process, rolling process, machine maintenance section forwarding products section to the field management section. With respect to the block of shift work(morning, afternoon, and night shifts) by the type of work, the OIR of the night shift was higher than those of the morning shift in the steel manufacturing process or forwarding products section. The OIR of the machine maintenance section was slightly higher in the morning shift than those of the night shift. The OIR of the time of day of the shift workers reached a peak between 09:00 and 11:00. The OIR of a slight injury to shift workers decreased across the night, afternoon, to morning shifts whereas the OIR of a serious injury tended to decrease across the night, morning, to afternoon shift. The body parts most commonly injured were the arm and the crus.

• 경영정보학연구
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• 제10권3호
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• pp.133-153
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• 2008

정보화 사업에 대한 투자성과가 언제부터 어떻게 나타날 것인가의 시차 연구는 정책개발 및 정보시스템 도입 시 의사결정에 중요한 연구이다. 그러나 대부분의 정보화 성과평가 방법론들은 평가시점에 따라 사전/과정/사후평가의 한 시점에서 평가할 뿐 시간 경과에 따른 정보를 제공하는데는 한계가 있다. 이에 본 연구에서는 정보화 효과 분석 및 시차와 관련한 선행연구들을 살펴보고 전자정부 사업의 일환으로 추진된 산업인력정보화 사업의 워크넷 시스템에 대한 시차효과를 파악하는 방법론을 제시하고, 이를 실증 분석하였다. 본 연구에서는 DB 데이터를 이용한 시차분석, 이용자들의 업무프로세스 분석을 통한 시차분석, IT투자 대비 효과를 이용한 시차분석 등 다양한 관점에서 시차효과 분석방법을 제시하였다. 또한 다양한 시차효과 분석방법을 국가인적자원개발 및 노동시장활성화를 지원하는 워크넷에 적용하여 검증을 시도하였다. 본 연구를 통해 시차분석을 위한 몇 가지 방법론을 제시하였으며, 산업인력 정보화사업의 성과가 시차를 두고 향상되었다는 것을 발견하였으며, 정보화와 성과 간에 발생하는 시차현상의 존재 가능성에 대한 시사점을 제시하였다.

• 한국정밀공학회지
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• 제10권2호
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• pp.114-125
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• 1993

In the present study the newly developed CAD/CAM system is applied to the process of the molding design, machining for mini-sized and precise processive die, and the production of press-stamped parts. When the design of a die was completed by means of CAD, wire cut NC data were generated with the aid of a design drawing in the CAD system and then inputed into the wire cut machine, and with the aid of a hole chart which had been made for this purpose, all the data were classified into the categories of CNC milling, jig boring, jig grinding, and machine center, and then developing a program of generating NC data, errors in process were reduced and programming time was shortened. The program was developed by using Autolisp language which was built-in the CAD, and realizing the intergation of designing a die, generating and processing NC data directly by a designer, designing time and machinery processing time were shorted. And the traditionally required working time for design. NC program required 6 days of work becomes 4 days of work by using the developed CAD/CAM system so that the efficiency shows 150% of the reduction working time. The prpgram of the design of the automation a progressive die mold was developed in the PC-Class Autocad system, therefore development expense could be reduced, and the integration of the CAD/CAM of the progressive die mold with the standard DB being built could be realized.

• 산경연구논집
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• 제8권7호
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• pp.63-70
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• 2017

Purpose - Due to the lack of physical activities and the increase of sedentary behaviors such as screen time, the health condition for contemporaries has been deteriorating. This study is designed to investigate how the use of worktable or tools unfit for body and sedentary behaviors can exercise influence on muscular skeletal disease and how it has an impact on lowering work efficiency and the quality of life with the medium of the muscular skeletal disease. Research design, data, and methodology - The research has developed a questionnaire with 5 hypothesis. The questionnaires were also made by interview and E-mail. 350 copies of questionnaires were distributed and 315 questionnaire were used for the analysis as valid data responses. SPSS ver.22.0 were used and made Cronbach's and reliability test, correlation, Baron & α Kenny 3 step mediated regression analysis. Results - The research has found that living environment factors have positive effect on the occurrence of musculosketal disease. Particularly, repeated use of unfit worktable or tools has a positive effect on the muscular skeletal disorder. And sedentary lifestyle also has a positive effect on the disease. The musculoskeletal disease caused by living environment has a positive impact on lowering the work efficiency. This study has also showed that the muscular skeletal disease has mediated the relationship between the living environment factors and the decrease of work efficiency due to musculoskeletal disease. The musculoskeletal disorders can effect the decrease of the quality of life as well, for the decrease of work efficiency has a positive effect on lowering the quality of life. Conclusions - Sedentary lifestyles, the use of worktable unfit for body, and the repeated use of a tool have caused the increase of muscular-skeletal diseases, and reduction of productivity as well as the hight cost of medical treatment for our contemporaries. Understanding the cause of disease morbidity, finding ways to prevent the disease, and educating people about them would contribute not only to improvement of individual health but also to the advancement of welfare for all.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.410-413
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• 1997

Recent general press brake has many problems in cutting high accurate products in the progress of industry. Previous hand-operated press brake needs many pre-processing works to adjust bending angle and marking-off works to calculate bending length. Also, The hand-operating work makes many geometric errors and has difficulty for variety-mass production. To solve these problems, this paper proposes Computer Numerical Control (CNC) general press brake and development of servo-control system based on database for reduction of geometric errors and pre-processing work time.

• 한국사회정책
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• 제23권1호
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• pp.227-256
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• 2016

본 연구는 노인 재가서비스의 확대가 노인을 돌보는 가족 구성원의 생활시간에 미친 효과를 분석하였다. 고령화와 가족구조의 변화 등으로 노인에 대한 가족의 돌봄부담이 가중되면서 공적 노인돌봄서비스를 확대해야 한다는 사회적 공감대가 형성되었고, 2000년대 이후부터 관련 제도가 본격화되었다. 본 연구에서는 가족의 노인돌봄 부담을 구성원이 직접 노인을 돌보는 부분과 이로 인해 노동이나 가사, 여가 등의 다른 주요 생활에 제약을 받는 부분으로 구분하고, 노인 재가서비스의 확대로 이러한 부담이 감소하였는지를 확인하였다. 분석자료는 통계청의 생활시간자료를 이용하였으며, 제도 확대의 효과는 건강이 취약한 노인을 돌보는 중하위 소득수준의 가구를 처치집단으로 삼아서 비교적 건강한 노인을 돌보는 가구 및 고소득 가구와의 비교를 통해 제도 효과를 추정하는 삼중차이(DDD) 방법을 통해 확인하였다. 분석결과, 노인 재가서비스의 확대는 노인을 돌보는 가족 구성원의 노인돌봄 시간을 감소시켰다. 이는 제도 확대의 목적과 부합하는 결과이지만, 돌봄 시간의 감소 정도가 크지 않았고, 여성 가구원에게만 그러한 효과가 관측되었다는 점에서 한계도 드러났다. 또한 노인돌봄 시간이 감소한 여성 가구원의 경우에도, 가사, 노동, 여가, 비노인돌봄 및 개인유지 등의 다른 생활시간 범주에서는 유의미한 변화를 보이지 않았다. 가족의 노인돌봄 부담을 실질적으로 줄이기 위해서는 공적돌봄의 대체효과를 높이기 위한 노력이 더 필요해 보인다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.78-78
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• 2013

Recently, many platinoid metals like platinum and ruthenium have been used as an electrode of microelectronic devices because of their low resistivity and high work-function. However the material cost of Ru is very expensive and it usually takes long initial nucleation time on SiO2 during chemical deposition. Therefore many researchers have focused on how to enhance the initial growth rate on SiO2 surface. There are two methods to deposit Ru film with atomic layer deposition (ALD); the one is thermal ALD using dilute oxygen gas as a reactant, and the other is plasma enhanced ALD (PEALD) using NH3 plasma as a reactant. Generally, the film roughness of Ru film deposited by PEALD is smoother than that deposited by thermal ALD. However, the plasma is not favorable in the application of high aspect ratio structure. In this study, we used a bis(ethylcyclopentadienyl)ruthenium [Ru(EtCp)2] as a metal organic precursor for both thermal and plasma enhanced ALDs. In order to reduce initial nucleation time, we use several methods such as Ar plasma pre-treatment for PEALD and usage of sacrificial RuO2 under layer for thermal ALD. In case of PEALD, some of surface hydroxyls were removed from SiO2 substrate during the Ar plasma treatment. And relatively high surface nitrogen concentration after first NH3 plasma exposure step in ALD process was observed with in-situ Auger electron spectroscopy (AES). This means that surface amine filled the hydroxyl removed sites by the NH3 plasma. Surface amine played a role as a reduction site but not a nucleation site. Therefore, the precursor reduction was enhanced but the adhesion property was degraded. In case of thermal ALD, a Ru film was deposited from Ru precursors on the surface of RuO2 and the RuO2 film was reduced from RuO2/SiO2 interface to Ru during the deposition. The reduction process was controlled by oxygen partial pressure in ambient. Under high oxygen partial pressure, RuO2 was deposited on RuO2/SiO2, and under medium oxygen partial pressure, RuO2 was partially reduced and oxygen concentration in RuO2 film was decreased. Under low oxygen partial pressure, finally RuO2 was disappeared and about 3% of oxygen was remained. Usually rough surface was observed with longer initial nucleation time. However, the Ru deposited with reduction of RuO2 exhibits smooth surface and was deposited quickly because the sacrificial RuO2 has no initial nucleation time on SiO2 and played a role as a buffer layer between Ru and SiO2.

• 대한디지털의료영상학회논문지
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• 제14권1호
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• pp.13-20
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• 2012

In a normal x-ray examination, the cooperation of a patient in positioning greatly influences the improvement of work performance, the quality of the images and the reduction in time spent on the examination. An attempt was made to discover the connection between an examination information printout and the effects of the examination by informing the patient before the examination on the examination positions in order to increase the level of cooperation by the patient and by surveying the degree of satisfaction of the patient during the examination proceedings. An examination information printout was prepared on five positions that patients consider to be difficult while receiving normal x-ray examinations and were shown to 257 male and female patients between the ages of 30 to 79 who had visited this hospital between January 1 to February 29, 2012 or to a person who had accompanied the patients before the examination to research the degree of satisfaction regarding the printout. In addition, the examination explanation printout was given to Radiologic Technologists with over 1 year experience in this hospital to use while taking the x-rays and the degree of satisfaction was surveyed and it was examined if the increase of the degree of satisfaction had an effect on the reduction in the examination time. The patients who utilized the examination information printout revealed results of approximately a 7.8% higher degree of satisfaction among the patients who had previous experience receiving x-ray examinations compared to those were having an x-ray for the first time. In the age groups between 30 to 70 years of age, the age group in the 30's revealed the lowest level of satisfaction at approximately 69% and the group in the 50's showed the highest degree of satisfaction of 87.94%. In the survey of the Radiologic Technologists, 85% responded that they were satisfied. In the question that stated "Will the examination information printouts reduce the time involved in unnecessary conversations with the patients?," the responses showed a 95% degree of satisfaction. The degree of satisfaction was high over the examination information printout by both the patients and the Radiologic Technologists. Although the effects of examination time reduction varied based on the ages of the patients and physical conditions that they were in and could not be given measurement values, it was able to be seen through the survey that reduction of the unnecessary communication between the patient and the Radiologic Technologists contributed to the increase in the degree of satisfaction. As a result, both the patients and the Radiologic Technologists had an increased degree of satisfaction over the examination information printout and it was possible for improvements to be made in the quality of medical service provided as well. Nevertheless, it is considered that a more developed manual in terms of quality and quantity must be produced using a more systematic approach and design.

• Nuclear Engineering and Technology
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• 제54권5호
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• pp.1902-1908
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• 2022

In many of the complex systems modeled in the field of nuclear engineering, it is often useful to use linear regression-based analyses to analyze relationships between model parameters and responses of interests. In cases where the response of interest is calculated by a simulation which uses Monte Carlo methods, there will be some uncertainty in the responses. Further, the reduction of this uncertainty increases the time necessary to run each calculation. This paper presents some discussion on how the Monte Carlo error in the response of interest influences the error in computed linear regression coefficients. A mathematical justification is given that shows that when performing linear regression in these scenarios, the error in regression coefficients can be largely independent of the Monte Carlo error in each individual calculation. This condition is only true if the total number of calculations are scaled to have a constant total time, or amount of work, for all calculations. An application with a simple pin cell model is used to demonstrate these observations in a practical problem.