• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.153-160
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• 2021

Nitrous oxide is a global warming substance and is known as the main cause of the destruction of the ozone layer because its global warming effect is 310 times stronger than carbon dioxide, and it takes 120 years to decompose. Therefore, in this study, we investigated the characteristics of NOx emission from N2O reduction by thermal decomposition of N2O. Bunsen premixed flames were adopted as a heat source to form a high-temperature flow field, and the experimental variables were nozzle exit velocity, co-axial velocity, and N2O dilution rate. NO production rates increased with increasing N2O dilution rates, regardless of nozzle exit velocities and co-axial flow rates. For N2O, large quantities were emitted from a stable premixed flame with suppressed combustion instability (Kelvin Helmholtz instability) because the thermal decomposition time is not sufficient with the relatively short residence time of N2O near the flame surface. Thus, to improve the reduction efficiency of N2O, it is considered effective to increase the residence time of N2O by selecting the nozzle exit velocities, where K-H instability is generated and formed a flow structure of toroidal vortex near the flame surface.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.7
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• pp.129-135
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• 1999

We developed a new measuring equipment which makes it possible to perform on-line measurements with the merits of its implicity and the time-saving characteristics. By using the newly developed measurement system, the amount of aeration is directly measured on several parameters, i.e, engine speed, oil quantity, oil deterioration, oil temperature and viscosity, etc. It showed that oil aeration is strongly related to be gas movements in crankcase and the residence time of circulating oil in oil pan. In addition, in order to clarify the mechanism of aeration and to quantify the degree of aeration, a modelling analysis to predict aeration was performed , and as a guiding parameter, Aeration Index was defined. Finally, the parameter was compared with the actual amount of aeration, and it was confirmed that they gave a good correlation with each other.

• Korean Institute of Interior Design Journal
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• v.24 no.3
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• pp.156-164
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• 2015

Nursing Homes do not have a defined standard in the space area nor does it have a detailed standard facility requirement by law. This can possibly lead to the deterioration of the facility and the system. This directly affects the medical treatment space area within the nursing home. The medical treatment area provides medical treatment to seniors and this is where the seniors get most of their daily services. Therefore, this is research is about the study of the space area of the medical center and the ratio trend of the space area for the medical treatment facility located in senior nursing homes. Ten facilities have been selected in this study to analyze the correlation factors between space area and its trends. The analysis performed includes the conditions relating to the area and what affects the center. We have followed up with a proposal for improvement of the facility and area configuration for the medical treatment facility. Based on the analysis, the following conclusion can be made: First, the senior welfare centers are mostly used as a residence purpose followed a temporary stay of residence facility for the seniors. Second, research indicates that the bigger the facility, nursing and public functions took a larger portion of the space area compared to other services within the senior welfare centers. Third, the study shows the management space area took up about 1%~6% of the entire medical center within the nursing home which is a narrow space area because of the integrated management. Fourth, analysis based on the trend in the time-series indicate after the adoption of the system, there is a continued decline in the space area of nursing, management and public areas. Lastly, since before and after 2008, the space area composition of the nursing facility shows a continuous decline in our study. We can safely conclude that the revised senior welfare act's construction plan has an effect in the facility and is effectively working to meet its requirement. Therefore, the revision of the law is required to reflect the social needs of the residents.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4656-4663
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• 2010

In this study, the 3D computational fluid dynamics (CFD) was performed in relation to the internal fluid characteristics, flow distribution, air mean ages, and residence time for the development of the most optimal model in the complex post-disposal device. As it is expected that a channeling (drift) would be made by the semi-dry reactor due to the large difference in the flow distribution by the compartment in the bag filter, a structural improvement should be urgently made for more uniformed flow distribution in the bag filter. In addition, it showed the possibility that the velocity field and distribution characteristics of the residence time could be improved through a modification to inlet structure of the spray dryer reactor. The complex post-disposal device, modified and supplemented with this analysis, integrated the semi-dry reactor and the bag filter in a single body, so it follows that the improvement can make the device compact, the installation area, the operation fee, and management more convenient.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2004.11a
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• pp.211-220
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• 2004

This paper suggests a collaborative business process between the companies that each has a restricted physical branch in its own area and wants to extend globally sales and delivery service. The companies integrate their business processes for sales and delivery using a shared product taxonomy table. We also suggest a similar product finding algorithm to make the product taxonomy table that defines product relationships to exchange them between the companies. The main idea of the proposed algorithm is using a multi-attribute decision making (MADM) to find the utility values of products in a same product class of the companies. Using the values we determine what products are similar. It helps the product manager to register the similar products into a same product sub-category. The companies then allow consumer to shop and purchase the products at their own residence site and deliver them or similar products to another sites.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.589-593
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• 2007

In the mechanical ventilation system, it is a fundamental condition to distribute the air equally to the each room. In this study, distribution performance of the air distributor which generally connected to a circular duct was investigated by simulation and experiment. In the first CFD analysis, maximum air flow rate deviation was an 63% in the air distributor model. After numbers of model modification and simulation, maximum flow rate deviation was reduced to 19% in the final simulation model. An air distributor which used in the experiment was produced by using data obtained from the final analysis. When experimental result was compared with analysis result, there was a deviation difference as much as 9%.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.3
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• pp.121-128
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• 2007

The purpose of this study was to investigate the removal efficiencies of HCl in dry reactor and Bag-Filter system. The bicarbonate was used as adsorbent to measure the HCl removal rate. The performance of bicarbonate was evaluated to investigate the removal efficiency. It was analysed that the best operation condition in using bicarbonate in process. The operating parameters was residence time, stoichiometric ratio, temperature and pressure. The Residence time was 1.5 sec, stoichiometric ratio was 1SR, 1.25SR, temperature was $160^{\circ}C$, $180^{\circ}C$, $200^{\circ}C$ and the bag filter pressure was 210mmAq, 230mmAq, 250mmAq. In this study it was found that the stoichiometric ratio and pressure can be effected in removal of HCl however the removal efficiency do not depends on temperature. The best operating condition was on 1SR, 230mmAq and $180^{\circ}C$ respectively and in this condition the best removal rate was 99.50%.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.2
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• pp.153-161
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• 2011

Creating standards on thermal environment has been organized traditionally based on the youth and the manhood who are in mainly active layer of a society. However, traditional creating standards have differences from the physiology of the aged who have weak physical ability than younger person. As a result, it causes a health problem of the aged. Therefore, In this study, we had a basic study to create a comfortable thermal environment which had considered to a physical ability and a physiology of the aged, and build a ecological residence space to maintain health. We had several experiments with the aged; Experiment, Comfort Sensation Vote, Mean Skin Temperature and Analyzing HRV. The result have following by: 1)For the aged, the summer recommend temperature, $26^{\circ}C$, is appropriate within first 30 ~ 40 minutes, but it should be increasing the temperature after that time. 2) By considering PMV status and thermal feeling of the aged, they are prefer to higher temperature than normal setting of air-condition system. 3) In the condition of the summer recommend temperature, $26^{\circ}C$, they had answered in neutral or comfort with the comfort sensation vote. However, we had figure out that they had stress in a lower temperature by analyzing the result of HRV.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.191-195
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• 1999

An integrated wastewater treatment pond system is developed for treatment and recycling of excreta from dairy cattle. It is composed of three ponds in series. A pit with a capacity of $10m^3$, 2-day hydraulic residence time, and overflow velocity of $1.5m^3m^{-2}day^{-1}$ is located internally in primary pond. It is designed for efficient sludge sedimentation and effective methane fermentation. It receives $5m^3/day$ of diluted cattle excreta by the water used for clearing stalls. A submerged gays collector for the recovery of methane is installed on the top of the pit. The average BOD_5 concentration of influent is 398.7mg/l. That of the effluent from primary pond is 49.2mg/l. About 88% of BOD_5 are removed in primary pond. It is assumed that about 60% of the influent BOD_5 is removed in the pit and that almost all of the carbon of the removed BOD_5 in the pit is converted to methane and carbon dioxide. Methane fermentation of the pit is well established at $16^{\circ}C$. This phenomena results from temperature stability, complete anaerobic condition, and neutral pH of the pit. Gas from the collector is almost 90% methane, less than 9% nitrogen, and less than 1% carbon dioxide. Thus a purified methane is produced, which can be used as energy source.

• Journal of the Korean Institute of Rural Architecture
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• v.1 no.2
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• pp.53-62
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• 1999

The first of 2000's, Korea will be changed the aging society. And then the many of aged Korean are respected to live alone or with their wives/husbands at the housing for the elderly. Therefore the demand of the housing for the elderly will be increasing rapidly in Korea but it is difficult to provide it to them. The housing policy for the elderly in Korea is not definite so far. For the development of the housing policy for the elderly in Korea, the process of this study is as follows. 1st, The consideration of the residence consciousness of the elderly in Korea. 2nd, Focussing around the welfare of the aged act and the arrangement of agricultural and fishing villages act, the analysis of the housing policy/system for the elderly. 3rd, In conclusion, a proposal for the development of the housing policy for the elderly.