• Journal of Energy Engineering
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• v.15 no.3 s.47
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• pp.154-159
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• 2006

An experimental study has been performed to investigate the correlation on compressor discharge temperature of capacity modulated system A/C in cooling mode. Indoor and outdoor temperatures, the cooling capacity, compressor discharge temperature and loading time are measured by the psychrometric calorimeter. The system is controlled by applying the scroll compressor operated by PWM valve and loading duty. With decreasing outdoor temperature, the cooling capacity increases. But, with decreasing indoor temperature, it decreases. According to the increase in outdoor temperature and loading duty, compressor discharge temperature increases. From these experimental data, the correlation on compressor discharge temperature is proposed. The correlation obtained from the present study is agreed with the experimental data within $3^{\circ}C$.

• Journal of the KSME
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• v.35 no.10
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• pp.886-895
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• 1995

근래들어 도시의 집중화와 고밀도화, 교통량의 증대 등 사회구조의 급격한 변화로 각종 소음원 들이 증가하고 있으며 소음에 대한 일반인의 관심도 점차 높아지고 있다. 건물의 경우 한정된 공간에서 거주자의 생활을 보다 쾌적하고 편리하게 하기 위해서 각종 설비들이 증가되고, 이들 설비들은 대용량화하는 추세에 있다. 건물내 공간의 기능을 능률적으로 유지하기 위해 설치된 각종 장비(공기조화기, 펌프, cooling tower, 보일러, 냉동기 \ulcorner 발전기 등)에서 발생하는 소음이 직접 실내로 투과되거나 이들이 발생하는 진동이 건물 구조체로 전달되어 실내소음을 야기시키는 경우가 많다. 따라서, 건물을 설계할 때는 실별 용도에 따라 허용소음도를 결정한후 이러한 실내 소음환경을 달성하기 위해 각종 조처를 강구하게 되는데, 이 글에서는 이러한 건물의 실내 소 음도 영향 평가의 하나로 특정 건물의 예를 들어 소음도 계산과 소음의 원인 및 대책에 관해 기술하고자 한다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.6
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• pp.518-523
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• 2003

The purpose of this study was to reduce the noise emitted from the package air-conditioner. The optimum design methods of the fans ware investigated experimentally through the analysis of noise problem caused by the conventional PAC system. New PAC system had decreased 6 dBA in overall noise level as compared with the conventional system by various technology.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.4
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• pp.8-11
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• 2004

최근 황사, 새집증후군(SHS), 조류독감 등과 같은 인간의 건강을 위협하는 요인들의 증가 및 대기오염에 의한 실내공기질의 악화는 비염, 천식과 같은 호흡기 질환과 아토피 같은 각종 알레르기 질환 관련 환자들의 증가로 실내의 공기를 건강한 공기로 전환시켜 이러한 질환들을 예방 또는 완화시키는 방법으로서 공기청정기에 대해 설명하고자 한다.(중략)

• Air Cleaning Technology
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• v.29 no.1
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• pp.43-50
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• 2016

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.175-176
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• 2015

봄철 황사나 대기오염으로 인하여 실내에 오염된 공기가 유입되고 있다. 이를 정화하기위해 현재 실내에서는 공기청정기를 사용한다. 그러나 기존의 공기청정기는 이미 실내공기가 오염되었을 때 작동한다. 이를 보완하고자 본 논문에서는 방충망형 오염공기 차단기를 제안하였다. 방충망형 오염공기 차단기는 방충망에 고압의 DC 전압을 인가하여 코로나현상을 일어나게 하도록 만든 장치이다. 코로나 현상이 일어나면 주변 공기가 이온화 되는 원리를 이용하였다. 고압의 DC 전압을 발생시키기 위해 Full-Bridge 인버터를 이용하여 LC공진으로 변압기의 1차측 전압을 상승시켰고, 권선비를 이용하여 변압기 2차측 전압을 승압하였다. 마지막으로 배전압 정류회로를 설계하여 최종 DC전압을 생성하였다. 실험을 통해 제안한 방식의 유용성을 검증하였다.

• Analytical Science and Technology
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• v.20 no.1
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• pp.17-24
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• 2007

This study was performed to investigate the distributions of volatile organic compounds and carbonyl compounds at the 120 households in new apartments before occupation. The concentration of toluene, m, p-xylene, formaldehyde, acetone and ethylbenzene dominated as $272.81{\mu}g/m^3$, $98.90{\mu}g/m^3$, $71.68{\mu}g/m^3$, $70.58{\mu}g/m^3$ and $49.76{\mu}g/m^3$, respectively. The identified compounds by standards occupied 42.5% of the TVOCs, also the concentration of toluene occupied the largest part of the identified compounds as 18.5%. The concentration of formaldehyde and acetone were 43.1% and 42.4% among carbonyl compounds. The indoor/outdoor ratio of the concentration of benzene, toluene, formaldehyde and o-xylene were investigated 1.29, 3.59, 10.76 and 28.74, respectively.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.51-56
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• 2008

이동컴퓨팅과 센서, GPS 기술의 발됨에 따라, 실외뿐만 아니라 실내 공간에서 이동객체의 위치 정보를 이용하는 다양한 응용분야들이 개발되고 있다. 그 중에서 이동 객체의 궤적을 이용하여 분석하는 응용분야들의 경우, 실제의 데이터를 획득하는 것이 불가능 하거나 이용이 제한되어 있어서, 실제의 속성을 반영한 합성 데이터를 이용하고 있다. 그러나 대부분의 이동 객체 궤적 생성치는 실내 공간에서 이동하는 객체의 특성을 잘 반영하지 못한다. 이에, 본 논문에서는 실내 공간에서 이동하는 객체의 특성을 살펴보고, 이를 반영한 실내 공간 이동 객체의 궤적 생성기를 구현한다.

• Journal of Internet of Things and Convergence
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• v.3 no.1
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• pp.25-31
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• 2017

In the future a future type new city and the latest apartment will be built, and the IoT technology will be constructed and combined in large numbers indoors of ordinary households. An air cleaner that makes people in it comfortable is built in, and the suction port that sucks in the air of the air purifier and the discharge port that discharges it are set up around the room and come out. However, this is impossible to adjust because there is only a central switch on / off. Also, consuming a lot of electricity so that many electricity charges are caused by huge electricity consumption will eventually be a waste of resources. This would like to be adjusted and driven through the fine dust detection device to the room built-in air purifier and that has provided a solution to save electricity. In addition, since it exists in and around the room, you can grasp the position of the person and connect to the home network to enhance the convenience. Also, through analysis of the air, we provide a health-check solution that checks the user's health and adjusts it appropriately.

• Clinical and Experimental Pediatrics
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• v.48 no.1
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• pp.27-33
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• 2005

Purpose : To determine incidence, characteristics and risk factors associated with intrauterine intraventricular hemorrhage(IU-IVH) among premature infants. Methods : The medical records of infants with intraventricular hemorrhage(IVH) admitted to the neonatal intensive care unit of Asan Medical Center from January 1999 to June 2003 were reviewed retrospectively. Infants whose IVH with cystic change were detected within five days of life were defined as the IU-IVH group. The control group included those without any IVH. Various maternal and neonatal factors were evaluated between the IU-IVH and control groups, and risk factors for IU-IVH were identified using multiple logistic regression analysis. Results : The incidence of IU-IVH was 49/1024(15.9%). Mothers who are younger, primiparous, use less antenatal steroid, and neonates with greater incidence of neonatal respiratory distress syndrome, had higher incidences of IU-IVH compared to neonates with normal neurosonography. Risk factors associated with IU-IVH included neonatal respiratory distress syndrome and placenta infarct by placenta biopsy. Most infants with IU-IVH were ${\geq}1,501g$, ${\geq}34$ weeks gestational age and had low grade IVH. The size of the cysts associated with IU-IVH remained the same or disappeared in 96 %. IU-IVH does not seem to affect short-term neurodevelopmental outcome although a longer period of follow-up is needed. Conculusion : IU-IVH occurred mostly in ${\geq}1,501g$, ${\geq}34$ weeks infants with grade I IVH without developmental delays. However, the high incidence of total IVH merits more attention in terms of awareness of its existence as an unusual IVH among premature infants.