• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1019-1024
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• 1999

Fifth one Nili-Ravi dairy buffaloes were studied in North-west Frontier Province of Pakistan. Rectal examination of reproductive organs was carried out on days 14 and 21 and then fortnightly. Milk samples were collected and analyzed for progesterone levels (MPL). Feed samples were collected fortnightly and analyzed. The buffaloes calving during the normal breeding season (NBS, August to January) (p<0.01) postpartum estrus interval of 55.95 days versus 91.15 days in those calving during the low breeding season (LBS, February to July). MPL in the LBS remained lower than the NBS (p<0.01). Shortest postpartum ovulation interval was noted during autumn(August to October), followed by winter (November to January), summer (May to July) and spring (February to April). The incidence of silent ovulations was during LBS than NBS (70.6% versus 29.4%). In autumn there was minimum intake of crude protein (CPI) and maximum intake of metabolizable energy (MEI, p<0.01). Calcium intake was higher in NBS than LBS calving buffaloes (p<0.01). Phosphorus, copper and magnesium intake was lower (p<0.05) and zinc intake was higher (p<0.01) in autumn, It was (p<0.05) and zinc intake was higher (p<0.01) in autumn, It was concluded that onset of breeding season was associated with increasing MEI and decreasing CPI and minerals intake.

• 에너지공학
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• 제7권1호
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• pp.1-6
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• 1998

본 연구는 국내 천연가스 수요관리 사업의 경제성 분석 방법을 다룬다. 국내 천연가스 수요는 하절기에 감소하고 동절기에 급증함에 따라, 이러한 수요 형태를 완화할 수 있는 천연가스 수요관리의 필요성이 대두되고 있다. 천연가스 수요관리 사업의 경제성 분석 결과는 해당 수요관리 사업의 추진 여부를 결정하는 주요 도구로 사용된다. 본 연구에서는 국내 천연가스 산업의 이원화된 공급구조를 감안하여 수요관리 사업의 참여자, 한국가스공사, 도시가스회사, 비참여자, 총자원 등 각 이해 당사자의 입장에서 천연가스 수요관리의 경제성 분석 방법을 제시하였다. 사례연구로는 향후 대표적인 에너지절약 사업이 될 것으로 예상되는 고효율 가스 보일러에 대한 경제성 분석을 하였다.

• 한국멀티미디어학회논문지
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• 제23권4호
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• pp.588-594
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• 2020

This study analyzes the current status of drone journalism in Korean broadcasting industry, with a case study of TV Chosun Company's drone use for news gathering. It analyzes TV Chosun's record of drone logs between 2014 and 2018. The log consists of date, time, news content, users, machine and on-air date. In 2014, the total of 31 cases of using drones for news gathering is identified, while in 2018, the frequency increases to 60, with a gradual, annual increase, making the total frequency of 160, during the period between 2014 and 2018. This means that the broadcasting company used the drone news gathering system every week. The analysis also reveals that the company used this drone news gathering system mostly in the metropolitan area in Korea, amounting to more than 76 per cent of its total use: 31.3 per cent in Seoul, 36.9 per cent in Kyunggi, and 8.1 percent in Incheon. The system was more frequently used in the summer and autumn than the winter and spring. Interestingly, it was first popularly used for disaster related news, but the use of drone for social and other issues is increasing every year, which may imply its diverse use in the future.

• Journal of Korean Society for Atmospheric Environment
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• 제24권E1호
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• pp.32-43
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• 2008

Source samples were collected to construct source profiles for 9 different source types, including soil, road dust, gasoline/diesel-powered vehicles, a municipal incinerator, industrial sources, agricultural/biomass burning, marine aerosol, and a coal-fired power plant. Seasonal profiles for 'Chinese aerosol', aerosols derived from the urban area of China, were reconstructed from seasonal $PM_{2.5}$ compositions reported in Beijing, China. Ambient $PM_{2.5}$ at a receptor site was also measured during each of the four seasons, from April 2001 to February 2002, in Seoul. The Chemical Mass Balance receptor model was applied to quantify source contributions during the study period using the estimated source profiles. Consequently, motor vehicle exhaust (33.0%), in particular 23.9% for diesel-powered vehicles, was the largest contributor affecting the $PM_{2.5}$ levels in Seoul, followed by agricultural/biomass burning (21.5%) and 'Chinese aerosol' (13.1%), indicating contributions from long-range transport. The largest contributors by season were: for spring, 'Chinese aerosol' (31.7%); for summer, motor vehicle exhaust (66.9%); and for fall and winter, agricultural/biomass burning (31.1% and 40.1%, respectively). These results show different seasonal patterns and sources affecting the $PM_{2.5}$ level in Seoul, than those previously reported for other cities in the world.

• 한국의류산업학회지
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• 제10권6호
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• pp.1023-1035
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• 2008

This study conducted a survey to find out dermatitis patients' preferred garment performance and their sentiment in spring/summer knitwears. SPSS 12.0 program was used for factor analysis, frequency analysis, T-test, ANOVA, and Duncan test. The result was as follows; First, in garments, patients required 'health hygiene', 'practicality in use care', 'skin contact' and 'easy movement'. Especially, 'skin contact' is an important property to be considered in patients' clothes. Second, in garment sensitivity, patients importantly considered 'modesty', 'feminine', 'boldness', 'decency', 'easy movement', 'youth', and 'simplicity'. Third, patients preferred simple and modest plain knitwear in light color with thin and soft fabric such as plain knit. And especially, dot pattern in knitwears should be avoided. Fourth, the preferred style of patients was that 'appropriately fit with suitable ease.' They also preferred 'front closed,' ; 'boat neckline' and 'V neckline'; 'raglan sleeve' and 'set-in sleeve'. For hem trim, they preferred 'rib'. Male preferred simple and plain style with round collar of 'tubular trim' and 'rib trim', while female preferred sophisticated and characteristic style with setin sleeve.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.156-161
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• 2011

In case of newly constructed buildings, the construction type is almost Curtain-wall system or large window in building skin. However, these kind of buildings have problems with regulations on building energy efficiency. And national regulations on building energy efficiency limit only the V-factor of window(except infiltration), it is hard to predict energy consumption of Curtain-wall buildings which gain large solar energy in summer. In this study, the influence of LSG(Light to Solar Gain) on energy performance was theoretically analyzed with simulation. LSG is the value of VLT divide SHGC and represents the optical performance of the glass or glazing. The Window & Therm program developed in LBNL was used to analyze window systems and EnergyPlus was used to building energy. Cases of glazing are three types; single coated Low-e clear glazing, tripple coated Low-e clear glazing, tripple coated Low-e tinted glazing. The results of this study are follows; 1) The building energy consumption of Alt-l, 2, 3 were about 300, 253, $259kWh/m^2{\cdot}yr$ respectively. Therefore, improvement of LSG could save the energy up to 16%. 2) The saved energy could be converted 1 billion won as annual benefit of total energy costs 3) SHGC and LSG more influence on cooling energy than heating energy in office buildings.

• 설비공학논문집
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• 제17권2호
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• pp.156-164
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• 2005

A comparative analysis of an ice storage system has been performed on the operation cost for the four control strategies, i.e., chiller priority and chiller downstream, chiller priority and chiller upstream, storage priority and chiller upstream, storage priority and chiller downstream. Main components of the ice storage system are an ice-on-coil storage tank and a screw compressor chiller. With the simulation program, the operation cost has been evaluated from the economics of an ice storage system. It is found that the operation cost of the ice storage system is strongly dependent on the control strategy, i.e., chiller priority or storage priority, but less affected by the arrangement method, i.e., chiller upstream or chiller downstream. In case of the maximum load day, the control strategy with chiller priority and chiller upstream is supposed to obtain the reduction of operation cost. However, it is found that the control strategy with storage priority and chiller downstream is the best economical operation for most summer seasons except the maximum load day.

• 설비공학논문집
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• 제20권4호
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• pp.280-286
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• 2008

In this study, characteristics simulation of heat pump system is investigated for heating and cooling using sewage water as a heat source. A simulation program for preestimate operation characteristics of heat pump system is developed. The performance of this system is resolved by several variables and the characteristics which is based on actual air and sewage temperature data. The simulation results agree well with the experimental values of COP. In the analysis of system characteristics, the COP is changed between $3\sim5$ in winter season for heating load, $4\sim6$ in summer season for cooling load. As the results of Life Cycle Cost analysis over a 15 year life cycle, the energy cost could be reduced by 250 million won if a heat pump system was used instead of a conventional boiler and an absorbtion refrigerator on the office building.

• 한국물환경학회지
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• 제30권2호
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• pp.184-198
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• 2014

For estimating discharge and pollution loads into the Yeongsan lake, a conceptual watershed model HSPF(Hydrological Simulation Program - Fortran) was applied to the Yeongsan River Basin. Various spatial data set including DEM, watershed boundaries and land uses were used to set up the model for the Yeongsan River Basin that was divided into 45 sub-basins. The model was calibrated and validated for the river discharges, SS, BOD, TN and TP concentrations against the data observed in 2011 at several monitoring stations. The simulation results show good agreement with the observed water flows($R^2$ = 0.46 - 0.97, NSE = 0.70 - 0.96). The simulated concentrations of SS, BOD, TN and TP are also in good agreement with the observed. The total freshwater discharge to the Yeongsan lake is estimated $2,406{\times}10^6m^3/year$ which the Jiseok and Hwangryoung stream contribute as much as 19%, 17% respectively. It is estimated that the total discharges to the Youngsan lake is SS 152,327 ton/year, BOD 15,721 ton/year, TN 10,071 ton/year, TP 563 ton/year. Both water and pollution loads are high in summer, particularly in July, when the monsoon season arrives at the Korean peninsula.

• 대한가정학회지
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• 제41권6호
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• pp.157-166
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• 2003

The purpose of this study was to provide information on how to improve the current design of infant coveralls through analysis of the design preferences of Korean consumer. In order to compile the information about preferences with the detail design of infant coveralls, a questionnaire was administered to mothers of 241 infants (aged under 36 months) living in Seoul, and analyzed using the SPSS WIN.10.0 program. The results of this study were as follows : 1) Results of buying conditions and design preference of infant coverall : To the question asking what kind of materials they preferred according to the season as material for infant coverall, the respondents preferred cotton hit as the materials for summer, but padding material for winter. The most favored design type were a flat collar, regular bodice type without cutting line, a raglan sleeves, snap front fastener, elastic band cuffs. 2) There is significant difference in preferred material and design among the month of age groups. 3) Analysis of the differences in preferred material and detail design according to gender In preferred material, it seemed as if girl baby group prefer cotton knit material, while boy baby group prefer padding material. There is definite difference in preferred neckline type, girl baby group prefer flat collar, while boy baby group prefer stand collar.