• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.727-734
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• 2008

This research presents a laboratory study about difference of subjective response between with and without pictures. A main source is impulsive sound caused by leisure shooting. The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of the jury test adopted a Semantic Difference(SD) Method. The intersection point which two lines crossed was used as reference point. The intersecting point of mean response rating between with and without pictures was approximately 44ASEL and that of %HA was about 60ASEL. In the result of the test, the negative effect of pictures was given at a lower levels than intersection point while the positive effect was given at a higher levels than that.

• 설비공학논문집
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• 제26권7호
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• pp.308-314
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• 2014

A heat pump has been considered as a thermal management unit for electric vehicles, including the heating and cooling of the cabin. However, the heat pump shows performance degradation at low outdoor temperatures or high compressor speeds. In this study, a R-134a heat pump for an electric vehicle was designed to improve system efficiency, by applying vapor injection with an internal heat exchanger. The heating performance characteristics of the vapor injection heat pump were analyzed at various compressor speeds and outdoor temperatures. The vapor injection heat pump showed 13.3% COP improvement over the non-injection heat pump, when the heating capacity was fixed at 5.2 kW. In addition, the heating capacity of the vapor injection system increased by 9.6%, as compared to the non-injection system.

• 교육시설
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• 제10권3호
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• pp.37-43
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• 2003

This study investigates the physical characteristics of indoor rest zones using the Space Syntax Method. A conceptual framework is based on analysis of design works presented in competitions(544 rest zones of 24 buildings on 7 campuses). The analysis on the unit type of rest zones showed that they were mostly available as open type, followed by semi-open type and outdoor rest places. On the other hand, by classifying the shape of whole building into traffic lines and nodal points, it was found that the buildings with 3 or more traffic lines have lower availability than others, because the buildings required more nodal points along a little higher complexity and zoning formed at increased nodal points between building masses. The analysis on the location of rest zones on traffic lines showed that hall type was most excellent in the level of availability. Finally, the analysis on the floor height showed that hall-like open rest places and outdoor places like rooftop garden functioned as a factor to enhance the integration of different spaces. In conclusion, this research will help the follow-up studies make spatial creation planning that may enhance the spatial efficiency and availability of Indoor rest zones on the campus.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.609-614
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• 2008

The heating and cooling performance of system multi-air conditioner under high-head and long-line conditions are experimentally investigated. The maximum head and tube length were 110 m and 1000 m, respectively. The experimental system was composed of 4 outdoor units with module systems, and 13 indoor units which were joined with the mode change unit by single-tube circuit. Field tests without indoor and outdoor temperature control were performed in a general office building with 22 different working conditions. Experimental results were prepared on the p-h diagram. Also the oil level in the compressor was normally maintained at the safety zone for the system multi-air conditioner with high-head and long-line conditions.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.304-309
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• 2008

The heating and cooling performances of system multi-air conditioner for various refrigerant flow rates with high-head and long-line conditions are experimentally investigated. The maximum head and tube length were 110 m and 1000 m, and the two different adjustments of refrigerant flow rates were +20 % and -20 %, respectively. The experimental system was composed of 4 outdoor units with module systems, and 13 indoor units which were joined with the mode change unit by single-tube circuit. Field tests without indoor and outdoor temperature control were performed in a general office building with two different refrigerant flow rates. Especially, the oil level in the compressor was normally maintained at the safety zone. Experimental results were prepared on the p-h diagram.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.291-296
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• 2009

This paper investigates the energy saving potentials of a dedicated outdoor air system (DOAS) applied to a highrise apartment building. As for a typical $132-m^2$ apartment unit, two different HVAC systems; centralized DOAS-Ceiling Radiant Cooling Panel and decentralized Energy Recovery Ventilator-Packaged Air Conditioner were installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program, and annual cooling coil load and heating load reduction potentials were compared. The research shows that DOAS-Ceiling Radiant Cooling Panel system can reduce the cooling coil load over 21% annually compared with the current Energy Recovery Ventilator-Packaged Air Conditioner pair. In addition, over 40% of annual ventilation heating load can be reduced by use of DOAS.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.285-290
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• 2009

The main thrust of this paper is to investigate acceptable supply air conditions of a dedicated outdoor air system (DOAS) for highrise apartment buildings. As for a typical $132-m^2$ apartment unit, it was assumed that centralized DOAS-Ceiling Radiant Cooling Panel was installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program. The optimized dew point temperature of the DOAS was discussed on the basis of the ASHRAE standard 62.1-2007 and the current Korean ventilation standard for apartments. It was found that the optimized dew point temperature of the DOAS supply air accommodating total latent load of a space is $11-12^{\circ}C$ and the appropriate supply air temperature of the DOAS is $11-12^{\circ}C$ in cooling period and neutral temperature of $18-20^{\circ}C$ in intermediate period.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1634-1640
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• 2012

The objective of this study was to compare pork characteristics and to determine consumer acceptability of pork chops from antibiotic free Yorkshire crossbreds sired by Berkshire (BY), Large Black (LBY), Tamworth (TY) or Yorkshire (YY) boars and reared in hoop houses. The experiments were conducted at the North Carolina Agricultural and Technical State University (NCA&TSU) Farm in Greensboro, NC and the Cherry Research Station Center for Environmental Farming Systems (CEFS) Alternative Swine Unit in Goldsboro, NC (source of antibiotic free Yorkshire sows used at both places). Twenty-four sows were artificially inseminated at each location in each of three trials. Litters were weaned at 4 wks old, and reared within deep-bedded outdoor hoop houses. To compare pork characteristics, 104 randomly selected animals were harvested at a USDA-inspected abattoir at approximately 200 d of age. Variables measured included pH, color score, $L^*$, $a^*$, $b^*$, marbling score, drip loss, hot carcass weight, backfat thickness (BF), loin muscle area (LMA), and slice shear force. Sensory panel tests were also conducted at two time periods. The data was analyzed with GLM in SAS 9.01 including location, trial, and sire breed as fixed effects. Backfat thickness, LMA, color score and $a^*$ were different among breeding groups (p<0.05). The LBY pigs had thicker backfat and smaller LMA than the other breed types. The TY and YY had less backfat than all other breed groups. Color score was lower for YY than BY and LBY but intermediate for TY. The $a^*$ was lower for TY than other breeds except LBY which was intermediate. For one sensory panel test, YY pork was more preferred overall as well as for juiciness and texture compared to BY and LBY (p<0.05), but no impact of breed type was noted for the other test, with values similar for BY, LBY, TY and YY pork. This information may help small farmers make decisions about breed types to use for outdoor production.

• 한국산학기술학회논문지
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• 제17권1호
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• pp.357-366
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• 2016

본 연구는 세종시 신설 초등학교의 학교규모와 배치계획의 개선점을 제시하기 위한 것으로 24개 학교를 대상으로 교지면적, 학교규모, 외부공간 구성비를 비교분석하였다. 연구결과 현재 초등학교 50학급 이상의 규모계획은 병설유치원 포함 48학급 이하로 조정이 필요하며, 학교규모 산정시 학생 수가 아닌 학급 수에 따른 기준을 적용해 교지면적 대비 적정 학급 수를 유지하는 노력이 필요하다. 교지 대비 교사면적은 평균 24.6%로 타 시도대비 높게 나타나고 체육장은 19.9%로 낮게 나타남으로 교사면적 비율을 20%대 초반으로 낮추어 체육장을 비롯한 외부공간의 구성비를 높여야 한다고 판단된다. 아울러 교지면적과 학교규모 산정시에 지구단위계획, 교지의 특수성으로 손실되는 면적을 고려하여 배치가능 면적과 외부공간으로 활용 가능한 면적을 구분하여 적용할 필요가 있다.

• 한국산학기술학회논문지
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• 제18권12호
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• pp.32-41
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• 2017

본 논문은 천안지역의 아파트단지 외부공간을 분석함에 있어서 공간구문론을 활용하여 구성요소 간의 관계성을 기반으로 하는 각 구성요소들의 배치 속성을 단지 전체 차원에서 해석하는 것을 목적으로 하며, 본 연구에 대한 예비 연구적 성격으로 진행하였다. 아파트단지 외부공간이 모두 연결되어 있는 하나의 공간구조라는 관점으로 거주자의 보행에 기반을 두고 각 공간 및 시설로의 출입공간에 대한 접근성 변화를 분석하였다. 총 5시기로 구분하고, 아파트단지 외부공간에 위치한 시설 및 공간으로의 출입공간을 단위공간으로 설정하였는데, 본 연구에서는 단지주출입공간, 주동 출입공간, 단지내 상가, 관리사무소/경로당, 어린이놀이터, 주민운동시설 등 총 6개의 분석항목을 설정하여 분석하였다. 분석결과 다음과 같은 결론을 얻었다. 첫째, 단지주출입공간의 접근성은 거의 모든 시기에서 높게 나타났으며, 주동 출입공간은 전반적으로 낮은 접근성을 보이고 있다. 둘째, 단지내 상가는 접근성이 향상되고 있는 경향을 보이고 있다. 셋째, 주민공동공간으로 볼 수 있는 관리사무소/경로당, 어린이놀이터, 주민운동시설 중에서 어린이놀이터의 경우는 예외적으로 통합도 순위가 시기별 큰 변화 없이 일정하게 높은 경향을 보이고 있고, 관리사무소/경로당의 경우는 최근으로 올수록 통합도 순위가 높아지는 경향을 보여 접근성이 좋은 위치에 주로 계획되고 있음을 나타내고 있다.