• 한국산업보건학회지
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• 제28권2호
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• pp.190-199
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• 2018

Objectives: The purpose of this case study is to assess the current airflow and find the ideal ventilation conditions in tank reactors for minimizing the possibility of exposure respiratory dusts(size of $2.5{\mu}m$, $10{\mu}m$) when workers exchange catalysts in the tank reactors. Methods: A Numerical study was performed to determine ideal ventilation conditions, We considered two sizes of airborne respiratory particles($2.5{\mu}m$, $10{\mu}m$) at 12points from the bottom of tank reactor. We changed input & output ventilation conditions and analyzed the particle motion in the tank reactor. The star-ccm+, computational fluid dynamics tool was used to predict air & particle flow patterns in the tank reactor and a numerical simulation was achieved by applying the realized ${\kappa}-{\varepsilon}$ turbulence model and the Lagrangian particle tracking method. Results: From the results, the increase of recirculation air had a significant impact on removing dusts because they are removed by HEPA filter. To the contrary, Increasing the clean air quantity or changing the input position of clean air is not good for workers because it causes the exit of respiratory dusts through workers' entrance or cause it to remail suspended in the air in the workplace tank.

• 한국입자에어로졸학회지
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• 제10권1호
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• pp.9-17
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• 2014

Several studies have been carried out on the source contribution of the particulate Polycyclic Aromatic Hydrocarbons (PAHs) over Seoul by using the Chemical Mass Balance Model (CMB)(Lee and Kim, 2007; Kim et al., 2013). To confirm the validity of the modeling results, the modified model employing a photochemical loss rate along with varying residence times and the standard model that considers no loss were compared. It was found that by considering the photochemical loss rate, a better performance was obtained as compared to those obtained from the standard model in the CMB calculation. The modified model estimated higher contributions from coke oven, transportation, and biomass burning by 4 to 8%. However, the order of the relative importance of major sources was not changed, coke oven followed by transportation and biomass burning. Thus, it was concluded that the standard CMB model results are reliable for identifying the relative importance of major sources.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 춘계학술대회
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• pp.99-101
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• 2009

IT 기술의 급속한 발달과 초고속망을 통한 인터넷 보급에 힘입어, 기업이나 공공기관의 사무실 중심으로 구축되던 네트워크 환경이 가정내의 디지털 전자기기로 확산되어 가면서 홈 네트워크 산업에 대한 관심이 높다. 홈 네트워크는 다양한 응용 분야들이 제안되어왔고 그 중 원격 모니터링 및 원격제어 분야도 지속적으로 연구되고 있다. 본 논문에서는 JAVA 확장 API인 JMF(Java Media Framework)를 사용하여 웹 상에서 홈페이지 접속을 통한 실시간 원격 영상 모니터링 시스템을 구현하였고, 원격제어를 위하여 홈 네트워킹의 대표적 무선 기술인 Zigbee를 이용한 조명 제어시스템 설계 방법을 제시한다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.105-107
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• 2009

IT 기술의 급속한 발달과 초고속망을 통한 인터넷 보급에 힘입어, 기업이나 공공기관의 사무실 중심으로 구축되던 네트워크 환경이 가정내의 디지털 전자기기로 확산되어 가면서 홈 네트워크 산업에 대한 관심이 높다. 홈 네트워크는 다양한 응용 분야들이 제안되어왔고 그 중 원격 모니터링 및 원격 제어 분야도 지속적으로 연구되고 있다. 본 논문에서는 JAVA 확장 API인 JMF(Java Media Framework)를 사용하여 웹 상에서 홈페이지 접속을 통한 실시간 원격 영상 모니터링 시스템과 홈 네트워킹의 대표적 무선 기술인 Zigbee를 이용한 조명 제어시스템을 구현 하였다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.185-191
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• 1999

In a mean time, arrangement of a arable land is lead by government with same way, same type. It means that there are no considering on characteristic features of region and aspect of ecological environment that can experess its natural charactersistics. Because whenever there is needed to be arranging , most of structure are made by a ward office from a desgin to a execution so that cause many public resentment and durability is very short by a inappropriateness its maintenance. The purpose of this study is divided into four parts ; First, to form the naturally favorable waterside spaces by performing the basic water controlling funtions of the irrigation channel and the drainage channel. Second, to provide the meeting place of the residents and to restrore the ecological system by means of the formation of the naturally favorable waterside spaces. Third, to lead to the optimal design and maintenance that residents want by inviting the residents to participate at the begining stage of planning. A district of this study is located on Songsam(13-14 zone), Samseung-Lee Ganam-Meon Yeoujoo-Gun Jyonggi Province and a length of section is 420m. This study came up with the following results. First, estabished the type of design and area of the area by means of the collected residents' opinions. Seconds, changed the straight line water channel already designed to the curve water channel . Third changed the structure materials of the steel concrete structure to the natural materials . Fourth, change dthe design by area for the ecological system and the meeting place of the residents. Fifth, divided the whole area into fourth area in order to satisfy the residents' requests.

• 한국식품영양학회지
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• 제19권2호
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• pp.193-200
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• 2006

The objective of this study was to identify factors affecting the job satisfaction of cooks employed in school foodservice and to propose a plan to improve school foodservice quality. Therefore, in this paper, we examined the job satisfaction of 119 elementary school foodservice employees in the Northern Gyeonggi Province using a 5-point scale method. The results were analyzed by the SPSS Package Program(Ver 12.0) to determine percentages and frequency. Among the employees, 99.2% were women, and 75.9% were employed by contract. All of the subjects worked in elementary schools with self operated foodservice system and 57.6% of them served food in the classroom. The total number of diners served by these foodservice programs was $1,391.6{\pm}307.6$ an average of $135.0{\pm}18.2$ diners per cook. Among the foodservice employees, 82.2% had completed high school academic courses, and 98.4% had never changed jobs. Their overall degree of job satisfaction degree was relatively high at $3.05{\pm}0.85$, but the wage and welfare system($2.45{\pm}0.86$), and the merit rating methods($2.25{\pm}0.87$) ranked among the lowest in the job satisfaction survey. On the other hand, the relationships between the managers and the coworkers marked relatively higher at $3.02{\pm}1.03$, compared with other aspects of job satisfaction. As for the work environment, the scaled score was $2.38{\pm}0.85$. Finally the ranking of achieving job improvement through education($3.28{\pm}0.93$), and the effectiveness of education($3.58{\pm}0.78$) showed us the importance and necessity of education.

• 한국환경교육학회지:환경교육
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• 제14권2호
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• pp.95-105
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• 2001

Out-door learning activity in environmental education has been emphasized as an effective method in environmental education since the aims of environmental education emphasize students'value, attitude, actions as well as knowledge. In order to implement successfully out-door learning activity in environmental education classrooms, teachers'perceptions to environmental problems and experiences at fields are essential. An environmental education network among the metropolitan city and provincial office of education, nongovernmental organization of environmental movement and education and university was established and a teachers'in-service training program of out-door learning centered environmental education was implemented. The program was developed in order to 1) connect environmental education with the regional environmental situations, 2) provide teachers with opportunities to participate in an out-door learning program, and 3) train teachers to be environmental education leaders of out-door learning. For evaluation of the program, responses of participants to questionnaire were analyzed. Most of teachers responded that their perception of environment was changed positively after the participation in the program. This study suggested that a future planning of a teachers'in-service training program of out-door learning centered environmental education should be developed in considerations of arranging enough hours for out-door learning at regional environmental sites, applying performance assessment, providing teachers with multiple opportunities with programs in different levels including enriched programs, and establishing an environmental education network among nongovernmental organization of environment movement and education, university, and local offices and department of education.

• 한국의류학회지
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• 제32권3호
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• pp.462-473
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• 2008

In recent years, Korea's apparel exports to the USA have faced a great threat, as the trade environment around the world has changed continually. The purpose of this study is to analyze the competitive position of Korean apparel exports to the USA, and to enhance export competitiveness by applying to offshore sourcing. The trade data of the Office of Textiles and Apparel(OTEXA) in the U.S. Department of Commerce were selected for inquiry about export competitiveness of apparel products made in Korea. In addition, we targeted members of the Korea Apparel Industry Association among the 500 exporters of clothing items in "The Import and Export Textile Product 2003." A total 70 sheets were analyzed. The results of this study were as follows: 1) Korean apparel exports to USA have decreased by 20-35 percent per year since 2005 under the Free Trade Area, showing that Korean apparel industries have not adapted to the new trade environment. Although Korean apparel exports to USA have indicated a trade surplus from now on, Korean apparel industries should find new ways to overcome this situation, diminishing exports and increasing imports. 2) Korean apparel companies selected more offshore sourcing than domestic sourcing. Also, as Korean apparel companies manufactured apparel products offshore, foreign subcontracting outranked manufacturing in their own foreign plants. When they chose foreign countries to source, they turned mainly to China and Vietnam. Also, they considered the target country's manufacturing price, labor stability, apparel products, quality, lead time, and so on. In order to increase apparel exports, Korean apparel industries should focus more on developing competitively new apparel products, improving the ability of sourcing management, and establishing on-the-spot agencies.

• KIEAE Journal
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• 제10권6호
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• pp.73-80
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• 2010

Since the Korean War, Korea has experienced modernization. The population increase by baby booming has asked for more space for educational facilities. In such a situation, the purpose of educational facilities was to accommodate continuously increasing students, rather than seeking for quantitative demands. In addition, in accordance with social changes, educational shifts were required. After the revision of the seventh national curriculum in education in 1997, the school buildings became varied. The design of buildings in accordance with educational curriculum has been improved, but still lack of forming comfortable environment and considering energy efficiency in school buildings. For the improvement of educational environments, educational media such as TV and computers have been provided, and energy systems, including heating and cooling systems, has been continuously increased. As a result, it appeared that energy use in school buildings and facilities has been steadily increased and that the structure of energy consumption has been also changed, especially with regard to electricity use. Living in the 21st century, human beings face global environmental issues, such as global warming, geographical climate changes, and ozone destruction that are the consequences of fossil energy use. Therefore, even in industrial areas, considering a counterplan for low energy use is being paid attention. Starting with Kyoto Protocol in 1992, people try to decrease carbon dioxide and to develop alternative energies (i.e. natural energy); for example, solar energy, wind force, terrestrial heat, and water power. Advanced countries already set up a criterion for $CO_2$ decrease ranging from office buildings to residential houses and also propose alternatives for the $CO_2$ decrease. However, there is no such a plan for low energy use and $CO_2$ decrease in school facilities, and any research on the actual conditions was not accomplished. Thus, this study examines energy demand in classrooms that take up a large portion of energy demand in school building structure.

• 한국수자원학회논문집
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• 제51권12호
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• pp.1207-1216
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• 2018

본 연구는 물리적 수리 수문모형의 적용이 제한적인 감조하천에서의 수위예측을 목적으로 하고 있으며, 이를 위해 한강 잠수교를 대상으로 딥러닝 오픈소스 소프트웨어 라이브러리인 TensorFlow를 활용하여 LSTM 모형을 구성하고 2011년부터 2017년까지의 10분 단위의 잠수교 수위, 팔당댐 방류량과 한강하구 강화대교지점의 예측조위 자료를 이용하여 모형학습(2011~2016) 및 수위예측(2017)을 수행하였다. 모형 매개변수는 민감도 분석을 통해 은닉층의 개수는 6개, 학습속도는 0.01, 학습횟수는 3000번로 결정하였으며, 모형 학습 시 학습정보의 시간적 양을 결정하는 중요한 매개변수인 시퀀스길이는 1시간, 3시간, 6시간으로 변화시키며 모의하였다. 최종적으로 선행시간에 따른 모의 예측능력을 평가하기 위해 LSTM 모형의 예측 선행시간을 6개(1 ~ 24시간)로 구분하여 실측수위와 예측수위와의 비교 분석을 수행한 결과, LSTM 모형의 최적의 성능을 내는 결과는 시퀀스길이를 1시간으로 하였을 때로 분석되었으며, 특히 선행시간 1시간에 대한 예측정확도는 RMSE는 0.065 m, NSE는 0.99로 실측수위에 매우 근접한 예측 결과를 나타내었다. 또한 시퀀스길이에 상관없이 선행시간이 길어질수록 모형의 예측 정확도는 2017년 전기간에 걸쳐 평균적으로 RMSE 0.08 m에서 0.28 m로 오차가 증가하였으며, NSE는 0.99에서 0.74로 감소하였다.