• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.33-35
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• 2013

The present work is an experimental investigation on potential operating range using directly injected gasoline fuel in a single-cylinder compression ignition (CI) engine. The objectives of present study were to apply auto-ignited combustion to gasoline fuel and to evaluate potential operating range. In order to auto-ignite gasoline fuel in CI engine, the fuel direct-injection system and the intake air system were modified that a flow rate and temperature of intake air were regulated. The heat-release rate (HRR), net indicated mean effective pressure (IMEP), start of combustion (SOC), and combustion duration were derived from in-cylinder pressure data in a test engine, which has 373.33cc displacement volume and 17.8 compression ratio. The exhaust emission characteristics were obtained emission gas analyzer and smoke meter on the exhaust line system.

• Nuclear Engineering and Technology
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• 제54권7호
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• pp.2510-2518
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• 2022

The main purpose of collecting and analyzing operating experience events is to look for insights to improve safety. The underlying assumption is the correlation and causality between events with different safety significances. The analysis of this assumption could be valuable to optimize operating experience feedback programs and to enhance safety. This paper analyses the correlation between events with different safety significances. Groups of events from six nuclear energy related databases are considered. The findings are that a correlation exists but with various levels and not as large or consistent as might be expected across different databases. These results might be the basis for further work to analysis causality, to find out how a similarity in causes influences the correlation, and finally to improve the operating experience program.

• 에너지공학
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• 제17권3호
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• pp.139-144
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• 2008

최근 유가의 고공행진 때문에 한국은 해외 에너지 자원개발뿐만 아니라 에너지 소비를 줄이기 위한 국가적 정책으로 기존 설비의 에너지 효율을 증가시키는 방안을 모색하는 것이 필요한 시점이다. 따라서 본 연구는 이런 국가적 사안에 부합하고자 인천생산기지 고압 LNG 배관망에 대하여 수정유량방정식을 사용한 Newton Method로 접근하였고, 유창조절밸브(FCV)에 의해 지배적인 영향을 받는 것을 확인할 수 있었다. 또한, 고압펌프는 유량조절밸브 50%의 개도율에서 최고효율을 보여 주었고, 고압배관망 내에서 배관저항곡선은 LNG 헤드가 1,500m 이상이 되어야만 토출이 가능한 것을 보였다. 고압펌프의 운전점으로부터 운전비용을 산출하였고, 최고 효율시 운전비용과 비교하여 운전비용을 절감할 수 있는 금액을 산출하였다. 특히 일간 시간대별 운전비용 절감액뿐만 아니라 연간 일별 운전비용 절감액을 산출하였으며, 그 결과 고압배관망은 연간 138백만원을 절감할 수 있다. 이것은 연간 고압펌프 1기당 9,823천원을 절감할 수 있다는 것을 의미한다. 결론적으로 본 연구는 복잡한 고압 LNG 배관망에서 고압펌프의 운전특성과 운전비용 절감효과를 확인할 수 있었다. 또한 이것은 미시적으로 생산기지의 효율적 미래운영에 대한 기여와 더불어 거시적으로 국가 에너지 경쟁력 제고에 기여할 수 있을 것이다.

• 대한건축학회논문집:계획계
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• 제34권8호
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• pp.43-50
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• 2018

The purpose of this study is to analyze the effect of architectural attributes on operating revenue by concentrating on the facility side and to investigate how much individual architectural factors can affect operating revenue. The time range of this study is limited to 2015, and the spatial range is limited to a tourist hotel in Seoul that can be easily surveyed and verified. The analysis method is to confirm the significance and influence of each attribute through regression analysis. According to the results, The room part such as number of rooms or area showed a relatively low correlation with "revenue per available room (Rev.PAR)" than "average daily rate (ADR)", but showed a high correlation with non - architectural attributes such as auxiliary facilities and chain. This shows that factors that influence the operating profit of hotel are not the part of the room but the other factors such as the auxiliary facilities work more. In addition, the presence of spa and the number of auxiliary facilities in the hotel have a positive effect on the operating profit of the hotel due to the non - architectural attributes. This is expected to provide a new direction for future research in studying hotel facilities.

• 산업공학
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• 제1권1호
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• pp.49-62
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• 1988

This paper deals with the case study that determines the best operating system of a container terminal using computer simulation techniques. For the simulation, SIMAN simulation language is used. The simulation model developed circumvents the dimensional restrictions imposed by the SIMAN package. Non-terminating simulation experiments are conducted for the 90 days' work on the basis of operation practices of real terminals.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 춘계학술발표대회
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• pp.972-975
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• 2013

This work developed a code analysis & extraction tool named Function Network Analyzer (FNA) to reduce the cost of software safety analysis. FNA analyzes functions and variables which a given function depends on, and extracts subset of code that can be compiled of automotive operating system, final resulting a well-ordered code sequence that can be compiled for model checking technique. And the experimental result illustrates that FNA can get 100% accurate rate and over 96% reduction rate by testing API functions from trampoline system.

• Architectural research
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• 제19권2호
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• pp.27-33
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• 2017

Advances in information and mobile technologies have changed the traditional firm ways of working very flexible, collaborative and innovative, resulting in the changes in work place structures and layouts. Despite the growing body of literature examining the novel ways of working, which is called smart work, there is little academic attentions paid to the spatial aspects of new work places, namely smart offices and smart work centers. This research explores the spatial changes of work places that improve business efficiency and collaboration among workers suitable for the novel ways of working. Conducting in-depth field surveys on selected cases, we analyzed the changes in spatial structure and operation policies of smart offices and smart work centers. From this survey, we observed that the new work places under study take various novel spatial forms and they have flexible operating policies such as flexible seating and flexible work hours. We also found that it would be difficult to change existing business practices and typical ways of performing tasks, without changing the bureaucratic spatial designs and layouts. Future studies are suggested to examine how spatial structures and layouts of offices have impacts on space utilization, collaboration, creativity, and job satisfaction.

• 한국조리학회지
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• 제12권1호
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• pp.188-202
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• 2006

With large corporations entering into the foodservice market, competitions among those foodservice providers became intense, leading to differentiated quality services in terms of portioning out the meal, its portion and waiting time, not to mention food quality. The purpose of providing foodservice is to satisfy its customers, to secure optimum level of profits, and attain continuous quality improvement. To have such purpose attained, all other factors affecting the foodservice should be allowed to play a role. The intensity of the work performed by the employees should be maintained at a steady level and systematically controlled. 'Service First’ principles upholding that customer satisfaction comes from good service should be applied at all times; customer satisfaction comes from the satisfaction of the employees. Customer satisfaction through good service will contribute to an increase in revenue which we get by subtracting operating expenses from the total sales, as it will lead to concluding a long-term supply contract or renewing the existing contract. To keep the operating expenses to the minimum level, it is important to effectively perform the cost control. Since personnel expenses occupy a large portion of the operating expenses, it is imperative to effectively control the labor costs. For this reason, this study will present an effective program for disposition of men with a large organization being centered around, where the number of people served at the mess hall varies greatly depending on a day of the week and a mealtime of the day.

• 지역사회간호학회지
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• 제9권1호
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• pp.213-222
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• 1998

The prevalence rate of low back pain in nurses is higher than that of other jobs, because there are many more risk factors(for example, standing postures, lifting and carrying heavy loads, transfering patients, changing a patient's position etc.). This investigation is to provide basic data for prevention of low back pain by analyzing the prevalence rate and related factors of low back pain in nurses(esp. operating room staff) in general hospitals. A self-reported questionaire survey was carried out on three hundred and five nurses of three general hospitals in Seoul from June, 1996 to August, 1996. Subjects of the survey were divided into a low back pain group(LBP) and a cotrol group to investigate the association between low back pain and the general characteristics and work related factors of each group. The results were as follows: 1. In the subjects of the survey, the prevalence rate of low back pain was 60.0% for the last year. 2. 73.6% of operating room(OR) staff complained of low back pain. 3. Standing for a long time and working in twisting postures were associated with low back pain, and so were the shift, the type of work, and the frequency of transfering patients. 4. The weight loads which nurses frequently carried were, under 5kg, 5-10kg, 15-20kg, 15-20kg, over 20kg, and all, except for 10-15kg, were associated with LBP. 5. 76.9% of the LBP experienced low back pain within 3 years after starting nursing jobs. 6. Concerning the degrees of low back pain: 75.8% was limited to waist; 18.8% reached the knees; 4.2% reached ankles. In conclusion, the prevalence rate of low back pain in general hospital nurses was associated with the works in operating room and other work related factors, therefore it is necessary to develop on educational program for the prevention of low back pain as well as and to improve working environments.

• 한국재난정보학회 논문집
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• 제8권4호
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• pp.319-327
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• 2012

본 연구는 대표적인 TMB 장비 회사인 독일 WRITH사에서 개발한 TMB 공법 적용 현장의 굴진보고서를 수집하여 작업운영 생산성을 분석하였다. 그리고 분석된 자료를 근거로 구경별(2.6m, 3.0m, 3.5m, 5.0m, 8.0m) 월굴진속도(m/월)를 도출하였다. 또한, 도출된 구경별 월 굴진속도를 근거로 독일의 WRITH사에서 구경별로 제시한 1m당 굴진에 소요되는 공사비 와 총공사기간을 산출하였다. 경암 40.0%, 연암 30.0%, 보통암 20%, 풍화암 10.0%로 구성된 암질을 기준으로 구경별로 도출된 월굴진속도, m당 공사비, 총공사기간은 향후 TBM 공법 적용시 기본계획단계와 기본설계단계에서 구경별 공사기간 및 공사비를 추정하는데 효과적인 활용 자료가 될 것으로 사료된다.