• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.1 no.2
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• pp.49-56
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• 1987

To save energy consumption, it is proposed to operate a discharge lamp with high frequency power. When designing a high frequency operating circuit containing a discharge lamp, the character of a lamp may be needed. And there are various methods to get and models for this. In this study, to present the volt-ampere character of a fluorescent lamp which gives a good saving effect, the nonlinear resistance model is suggested. And the validity of the model is verified by applying the model for the circuits with inductor ballast and capacifor ballast. This model, in contrast with the others, can be easily obtainable. And for comparison, the model using a modified Francis equation is examined. The method used in this study can be basically applied to the other discharge lamps. As a result, 1) Approximated 3rd order polynomial of nonlinear resistance model gives a good simulation result. 2) When operating in high frequency, the model using a modified Francis equation with constant coefficients can't be applied.

• Journal of Energy Engineering
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• v.22 no.1
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• pp.51-57
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• 2013

As energy becomes an important source of power for national competitive force, not only Government administrations but also private sectors are striving to save energy. The purpose of this study is to compare and evaluate energy consumption of the corridor with and without window when improving the energy environment by installing door and window on the open area of entrance for one-side corridor type apartment. The energy usage was examined through this improvement process and the energy consumption amount was compared and analyzed by simulation before and after the installation. It is desired for this study to contribute to the government's green remodeling project.

• Journal of Navigation and Port Research
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• v.34 no.8
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• pp.649-657
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• 2010

In order to achieve a sustainable competitive advantage in the expanding maritime transportation market, most shipping companies are making every effort to reduce transportation costs. Likewise, the car shipping companies, which carry more than 80% of total car import and export logistics volume, also do their utmost for transportation cost saving. Until now many researches have been made for efficient maritime transportation, but studies for car shipping companies have rarely been made. For this reason, this study has tried to develop a maritime transportation planning support system which can help to save logistics costs and increase a competitive power of car shipping companies. To this end, instead of manual effort to solve the routing problem of car carrier vessels, this study has proposed a genetic algorithm. The performance of the genetic algorithm will be evaluated by comparing with the optimal solution of integer programming model.

• Journal of the Korean Institute of Educational Facilities
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• v.7 no.3
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• pp.5-14
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• 2000

The purpose of this study is to analyze the environmental characteristics of Hansung Girls' Middle & High School located on the northern slope of Mt. Naksan in Seoul but sited at different aspects. The measured temperature and illumination in March, July and December were analysed. The proportion of window size and questionaries were used also. The results of observation are as follows: (1) The temperature of the southward classrooms was $3.6^{\circ}C$ higher than eastward or westward classrooms in March, but the difference of the both values in July were only $0.3^{\circ}C$ in the average. (2) The temperatures in December decreased in the order of aspects: southward, westward and eastward. (3) The highest values for illumination appeared in the classroom faced to the south and the values decreased from westward to eastward. (4) Temperatures and illumination were varied not only with the aspect but also with the number of story and the proportion of the window size. However, the heating facilities and illuminators are installed evenly without considering the condition of the buildings. The heating facilities should be installed differently according to the direction and height of the story of the building. The heating facilities should be installed sparsely for the classrooms faced southward, and more densely near the hallway side to achieve satisfaction of students and to save expenses of heating. It will be better that electric power switches for window side have to be set separately from hallway side. Improvement of the condition of illumination and temperatures will help students to promote their health and learning.

• Journal of the Korean Solar Energy Society
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• v.32 no.2
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• pp.64-73
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• 2012

The angle of solar panels is calculated using solar radiation model for the efficient solar power generation. In ideal state, the time of maximum solar radiation is represented from 12:08 to 12:40 during a year at Gangneung and it save rage time is12:23. The maximum solar radiation is 1012$W/m^2$ and 708$W/m^2$ inc lear sky and cloudy sky, respectively. Solar radiation is more sensitive to North-South (N-S) slope angle than East-West (E-W) azimuth angle. Daily solar radiation on optimum angle of solar panel is higher than that on horizontal surface except for 90 days during summer. In order to apply to the real atmosphere, the TMY (typical meteorological Year) data which obtained from the 22 solar sites operated by KMA(Korea Meteorological Administration) during 11 years(2000 to 2010) is used as the input data of solar radiation model. The distribution of calculated solar radiation is similar to the observation, except in Andong, where it is overestimated, and in Mokpo and Heuksando, where it is underestimated. Statistical analysis is performed on calculated and observed monthly solar radiation on horizontal surface, and the calculation is overestimated from the observation. Correlationis 0.95 and RMSE (Root Mean Square Error) is10.81 MJ. The result shows that optimum N-S slope angles of solar panel are about $2^{\circ}$ lower than station latitude, but E-W slope angles are lower than ${\pm}1^{\circ}$. There are three types of solar panels: horizontal, fixed with optimum slope angle, and panels with tracker system. The energy efficiencies are on average 20% higher on fixed solar panel and 60% higher on tracker solar panel than compared to the horizontal solar panel, respectively.

• Hwankyungkyoyuk
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• v.9 no.1
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• pp.58-71
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• 1996

The purpose of this study was to investigate the rural housewives' recognition and practice on environmental preservation. The subjects of this study were 300 rural housewives living in Chung-buk province. Questionaires were distributed to them during a week from August $25^{th}$ to August $31^{th}$ in 1995. Major findings were as follows: 1. The saved water quite well in washing their faces and the dishes compared with urban housewives, but they did not save water so well in using the lavatory. They used synthetic detergent, one of water pollutants, more often than natural soaps in shampooing and laundering. In addition, they did not use a measuring cup. It resulted in the waste of detergent and aggravation of water pollution. 2. Food waste was disposed of properly, but used batteries were not collected separately. A disposable vinyl bag was more commonly used than a reusable shopping basket. The reason for not using a shopping basket was bothering or uncustomary. Since most of them did not know refillable products of goods with environmental mark, they did not use those. Therefore, housewives should be educated in order to prevent soil pollution. 3. The use of spry-type pesticide and hair treatment, one of air pollutants, was wide-spread among them. They hardly recognized and practiced saving of electric power when they used household electric appliances. 4. The major source of environmental knowledge was mass media like TV of radio. Many of them did not know the practical ways to solve the environmental education program. In conclusion, low level of recognition and practice of rural housewives on environmental preservation indicated that a systematic environmental education program should be developed and implemented.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.3
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• pp.135-140
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• 2020

Since the process gas that is essential in the semiconductor process is a harmful gas, it is an essential task to solve it in an environmentally friendly manner. Currently, the cleaning technology used in the semiconductor process is mostly a wet cleaning based on hydrogen peroxide developed in the 1970s, and the SC-1 cleaning liquid for removing particles on the surface uses a mixture of ammonia and hydrogen peroxide. Therefore, environmental problems are caused, and economic problems caused by excessive water use are also serious. For this reason, the products developed through this study are used to decompose the process harmful gas from the chamber outlet into a harmless gas before entering the vacuum pump, or by incineration and the gaseous components are deposited on the pump. I want to solve the problem. In this paper, CPS (Confined Plasma Source) is proposed to save environment and improve productivity by replacing harmful gases (N2, CF4, SF6⋯., Etc) which are indispensable in semi-contamination process with innocuous gases or incineration with plasma, to study.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.229-234
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• 2013

The purpose of this study is to develop a lighting apparatus of the illuminance and color temperature to maximize the ability of the optimal combination of light sources that can be controlled efficiently control device. Finding people comfortable feeling for indoor lighting that can be used in a variety of color temperature illumination area by combining light sensitivity can be realized. Lighting apparatus for fluorescent lamps with different color temperature of 2000K and 8000K, and by varying the quantity of each of the fluorescent lamps, the illuminance of lighting equipment and color temperature through optical simulations were evaluated. By infrared remote control receiver, divided into 5 types of relaxation, conversation, meeting, hospitality, arts and the lighting environment you want to transfer the PC0 ~ PC4 through the parallel port on the mode selected by the user at the receiving end the DC voltage output. EEFL inverter input DC voltage and the DC input voltage, depending on the level of EEFL dimming value (illuminance and color temperature) lighting environment you want to create change while using a PIR sensor EEFL automatically turn off if people do not have was developed so that the power consumption so you can save.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.6
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• pp.637-644
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• 2010

The purpose of this study is to analyze characteristics of water quality factor scientifically and develop the multiple regression model predicting dissolved oxygen to save periodic replacement costs for dissolved oxygen sensor. Correlation analysis using the environmental data obtained from 2 different land-based fish farms of the Geogeum-do, Geheung-gun coastal area during the periods from November 2008 to January 2009 shows that water temperature was negatively correlated with dissolved oxygen and pH butpH was positively correlated with salinity and dissolved oxygen. The information of Keumho fish farm in 2009 is presented by the tables which are monthly statistics of water quality factors and seasonable difference by the Duncan's post-test. Also we developed multiple regression model predicting dissolved oxygen, the usefulness of which was verified by the comparison graph between estimates and actual observations. The developed regression model shows that seawater temperature and salinity give negative affect to dissolved oxygen while pH gives positive affect to it. Lastly the seawater temperature has much higher explanatory power than pH factor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.818-821
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• 2003

Ozonic use of sterilization and heat treatment of raw material to extend the conservation period of food recently is increased by hard vegetable or microorganism sterilization purpose of fruit. If ozone can create as is easy comparatively because do air or oxygen by raw material and schedule period passes, there is advantage that do not leave the second contaminant because being gotten restored by oxygen. Also, because the effect is big to decolorization beside sterilization effect about microorganism, deodorization, disjointing of venomousness hazardous substance, food save, indoor air purge, good hand processing, hydrospace agricultural chemicals processing etc. the use extent is wide. This research ran parallel a sterilization experiment of E.coli colitis germs by ozone that manufacture ozonizer that use doped diamond maund electrode (BDD) by boron and searched special quality electrochemistry enemy of the ozonizer and is created. E.coli. After cultivate E.coli colitis germs during 37C 1 day is LB ship, after do ozonation, was sterilized more than 90% by ozone as result that examine sterilizing power by substance microscope and could confirm excellency of diamond electrode.