• 한국환경보건학회지
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• 제33권4호
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• pp.250-254
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• 2007

The reduction efficiency of air cleaner on particulate contaminants such as dust, airborne bacteria and fungi distributed in the office was relatively higher in case of office with workers than office without workers. This result would be attributed to workers' activities and physical characteristics of particulate contaminants. The air cleaner decreased a concentration of airborne bacteria more than airborne fungi, which implicates that difference of dust adsorption between airborne bacteria and fungi would affect an operation efficiency of air cleaner.

• 한국정밀공학회지
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• 제14권1호
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• pp.84-89
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• 1997

Recentely, a compact and small size air-cleaning Electrostatic Precipitator(ESP) is needed to develop for air conditioning devices. From Deutsch formula for ESP efficiency, collection efficiency is affected not only the structure of collection section but also the charge rate of dust. In terms of collection area, the most useful type is a scroll type ESP. In this work, we investigated experimentally aptimum design factor of scroll type ESP by application of Taguchi method. And we developed the scroll type ESP by using optimal condition of control factor.

• 한국자동차공학회논문집
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• 제11권3호
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• pp.65-70
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• 2003

In this paper, an adapted TWC model and its application to the monitoring algorithm are proposed. As TWCs have the different characteristics, the model has to be corrected to diagnose more accurately. In the TWC model oxygen storage and release rate model are adapted to the installed TWC to whose characteristics related. The model learns from the downstream $O_2$ sensor output during the vehicle's operation. From the results, the model is adapted to the Installed TWC's characteristics. using this model, the monitoring algorithm can diagnose the no more accurately. Finally the algorithm is validated with simulations using the data logged from a retail car.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.830-833
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• 2002

최근 나노 구조 (nano structure)를 만들기 위한 시도 중 하나로서 스스로 조직화(self organization)하여 나노 구조를 형성하는 물질을 나노 소자 제작을 위한 형틀 (template)로 이용하려는 시도가 활발히 진행되고 있다. 이러한 물질로서 주목을 받고있는 것 중 하나가 전해질 용액에서 알루미늄을 양극산화(anodization) 시켰을 때 형성되는 다공성 알루미나 박막이다. 본 연구에서는 고 순도 알루미늄을 기계적으로 연마(mechanical polishing)하고 공기 분위기에서 어닐링 (annealing)하여 알루미늄을 재결정화(recrystallization) 시키고 인가 전압이 40 V인 정 전압하에서 0.3 M의 수산(oxalic acid)을 전해질로 사용하면서 양극산화를 수행하여 평균 직경이 65 nm인 고도로 배열된 육방밀집구조의 나노 다공성 박막을 제작하였다. 또한 같은 방향의 육방밀집 배열은 크기가 수 ${\mu}m$인 영역(grain)을 형성하고 있었으며, 평균적인 pore의 밀도는 $1.1{\times}10^{10}/cm^2$였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.253-254
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• 2009

본 논문은 노후화된 줄눈콘크리트 포장의 열화 원인을 평가하기 위하여 수행되었다. 콘크리트 코어 시편을 사용하여 ASTM C 457 에 의거한 화상분석(Image Analysis)실험을 실시하였다. 정화시편의 공기량, 공극구조분포 및 간격계수(Spacing Factor) 정보를 수집하고 공극구조와 관계한 내구성지수(Durability Factor)를 평가하였다. 평가결과 대부분 시험편의 간격계수가 250$\mu$m 이상으로 평가되어 동결융해에 취약한 것으로 나타났다.

• KIEAE Journal
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• 제5권4호
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• pp.3-8
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• 2005

The objective of this study is to examine the impact of the Phytofiltration system on the improvement of indoor air quality. Measurement was performed in a full-scale mock up model to examine the purification efficiency of air by plants. Seven species of plants, which were recommended by NASA, were used in measurements. Two species of plants that showed outstanding purifying effects were chosen for further measurements. The measurements were performed according to the positions and amounts of plants. Thermal environment, the concentration of Toluene and Formaldehyde were monitored. Ficus Benjamiana and Aglaonema brevispathum were excellent in diluting the concentration of contaminants. The effect of diluting concentration became better as the amount of plants increased. The reducing effect was the best when the plants were placed near window.

• 말소리와 음성과학
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• 제5권4호
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• pp.63-70
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• 2013

The purpose of this study is to show the aerodynamic characteristics and differences in muscle tension dysphonia and adductor spasmodic dysphonia to predict factors which will provide additional information while preparing for the objective examination standard to distinguish the two dysphonias. Forty-eight individuals diagnosed with muscle tension dysphonia and adductor spasmodic dysphonia participated in this study. PAS was used in order to find the aerodynamic characteristics for the two dysphonias. The outcomes of this study show that the airflow variation and glottal resistance of the two groups showed noticeable differences. This study concludes that the aerodynamic characteristics may be used as additional information on diverse evaluations to classify muscle tension dysphonia and adductor spasmodic dysphonia.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1330-1335
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• 2007

The HVAC and the air duct is to make optimal indoor environment. By the HVAC position, method and the air duct construction, the important elements can affect on cooling performance, passengers' convenience, and energy efficiency. According to this, there are features, such as the indoor temperature distribution, cooling performance, velocity distribution from diffuser, tend to be come out variously. Also, comparing and analysing temperature distribution, cooling performance, air velocity, noise based on the real practical vehicle tests, it shows features in detail. Besides, it can lead to make design the system of HVAC & air duct effectively.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2003년도 추계학술대회 논문집
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• pp.421-424
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• 2003

서울지하철은 총연장 286.9km에 1일 4226회의 운행회수 그리고 대중교통수단 중 총 34.1％의 최다 수송분담율을 담당하고 있다. 서울시의 도심교통문제 해결 방안으로 시민들에게 대중교통 이용을 적극적으로 권장하고 있으나, 지하철 역사의 환경문제는 답보 상태를 유지하고 있는 것이 현실이다. 지하철내의 먼지문제는 이미 심각한 사회문제로 대두된 지 오래이며 이를 개선하기 위하여 지하철공사와 도시철도공사에서는 환기시스템의 개선, 환기 및 공기정화시설의 설치 그리고 잦은 물청소실시 등을 시행하여 오고 있어 그간 상당한 효과를 이룬 것도 사실이다. (중략)

• 한국자동차공학회논문집
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• 제5권3호
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• pp.15-26
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• 1997

In this study, the theoretical investigation of the electrically heated catalyst(EHC) for vehicle application has been carried out using the thermal equivalence of EHC system and the data of vehicle tests to meet ultra low emission vehicle(ULEV) standard. To improve the efficiency of EHC system, it is necessary to understand relation between the power, the operating time and the conversion efficiency of EHC system. The relation was found with thermal equivalence of EHC system which considers the power supply to EHC, heat loss, chemical exothermic energy generated by oxidation reaction and net energy coming in via the exhaust gas. From this relation, the limits of needful power and operating time to meet the ULEV standard can be suggested, when the conversion efficiency of catalyst was known.