• Title/Summary/Keyword: AirKorea

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Analysis of performance test results of CA-certified air cleaners from 2003 to 2015 (2003년부터 2015년까지 CA 인증 공기청정기의 성능 시험 결과 분석)

  • Kim, Hak-Joon;Hong, Kee-Jung;Woo, Chang Gyu;Han, Bangwoo;Kim, Yong-Jin
    • Particle and aerosol research
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    • v.13 no.1
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    • pp.17-23
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    • 2017
  • In this study, the test results obtained from the performance tests for CA (Korea Association of Cleaning Air) certificated air cleaners which had been commercially available in Korea from 2003 to 2015 were analyzed. Among the test parameters such as flow rate, particle collection efficiency, clean air delivery rate (CADR), ozone emission, odor removal efficiency and noise level, noise level and CADR were correlated with flow rates. Collection and odor removal efficiencies were 20% higher than the limit of the CA certification. The ozone emissions from the air cleaners were negligible because all the air cleaners were equipped with only HEPA filters, not electrostatic precipitation method which produces ozone.

Sensitivity of Hot Film Flow Meter in Four Stroke Gasoline Engine

  • Lee, Gangyoung;Lee, Cha--Myung;Park, Simsoo;Youngjin Cho
    • Journal of Mechanical Science and Technology
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    • v.18 no.2
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    • pp.286-293
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    • 2004
  • The air fuel ratios of current gasoline engines are almost controlled by several air flow meters. When CVVT (Continuous Variable Valve Timing) is applied to a gasoline engine for higher engine performance, the MAP (Manifold Absolute Pressure) sensor is difficult to follow the instantaneous air fuel ratio due to the valve timing effect. Therefore, a HFM (Hot Film Flow Meter) is widely used for measuring intake air flow in this case. However, the HFMs are incapable of indicating to reverse flow, the oscillation of intake air flow has an negative effect on the precision of the HFM. Consequently, the various duct configurations in front of the air flow sensor affect the precision of HFM sensitivity. This paper mainly focused on the analysis of the reverse flow, flow fluctuation in throttle upstream and the geometry of intake system which influence the HFM measurement.

Analysis of Supply Airflow Control by a Stratified Thermal Model in a VAV System

  • Kim, Seo-Young;Moon, Jeong-Woo;Cho, Hyung-Hee
    • International Journal of Air-Conditioning and Refrigeration
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    • v.9 no.3
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    • pp.46-56
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    • 2001
  • The present study concerns the numerical simulation of a supply airflow control in a variable air volume (VAY) system. A stratified thermal model (multi-zone model) is suggested to predict a local thermal response of an air-conditioned space. The effects of various thermal parameters such as the cooling system capacity, the thermal mass of an air-conditioned space, the time delay of thermal effect, and the building envelope heat transmission are investigated. Further, the influence of control parameters such as the supply air temperature, the PI control factor and the thermostat location on a VAV system is quantitatively delineated. The results obtained show that the previous homogeneous lumped thermal model (single zone model) may overestimate the time taken to the set point temperature. It is also found that there exist the appropriate ranges of the control parameters for the optimal airflow control of the VAV system.

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Aerosol Wall Loss in Teflon Film Chambers Filled with Ambient Air

  • Lee Seung-Bok;Bae Gwi-Nam;Moon Kil-Choo
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.E1
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    • pp.35-41
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    • 2004
  • Aerosol wall loss is an important factor affecting smog chamber experiments, especially with chambers made of Teflon film. In this work, the aerosol wall loss was investigated in 2.5 and $5.8-m^3$ cubic-shaped Teflon film chambers filled with ambient air. The natural change in the particle size distribution was measured using a scanning mobility particle sizer in a dark environment. The rate of aerosol wall loss was obtained from the deposition theory suggested by Crump and Seinfeld (1981). The measured rates of aero-sol wall loss were In a good agreement with the theoretical and experimental values given by McMurry and Rader (1985), implying that the electrostatic effect enhances particle deposition on the chamber wall. The significance of aerosol wall loss correction was demonstrated with the photochemical reaction experiments using the ambient air.

Analysis of Factors Affecting Air Transport Trade between Korea and ASEAN Countries (한국과 아세안 국가간 항공운송무역 영향요인 분석)

  • Lim, Jae-Hwan;Kim, Young-Rok;Choi, Yun-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.27 no.4
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    • pp.44-51
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    • 2019
  • This study analyzes the trade patterns that occur between Korea and ASEAN countries through air transport, one of Korea's trade transport methods. In order to understand the detailed characteristics of the air transport sector, the dependent variables were analyzed by dividing them into amount and weight. As a result, the amount of exports, imports, and trade was proportional to GDP per capita representing income level, and inversely proportional to GDP representing national economic power. In terms of air transport weight, exports, imports and trade were all proportional to GDP representing economic power and inversely proportional to GDP per capita representing income levels. In addition, the national area acted as a factor to reduce the trade volume, and the number of airports and inland countries did not show any significant results.

A Study on Risk Factors by Analyzing Human Factors during Air Refueling Missions for Fighter Pilots (전투기 조종사의 공중급유 임무 시 인적요인 분석을 통한 위험요인 연구)

  • Koo, BonEan
    • Korean journal of aerospace and environmental medicine
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    • v.30 no.3
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    • pp.113-129
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    • 2020
  • With the operation of the KC-330 MRTT (Multi Role Tanker Transport), which had been fielded in 2019, the ROKAF (Republic of Korea Air Force) has given fighter pilots a new mission of air refueling. As a result, fighter pilots are more likely to be exposed to risks they have never faced before, and it is necessary to look at the risk factors associated with human factors in air refueling missions. Therefore, in this study, an analysis using the HFACS (Human Factors Analysis and Classification System) model was performed for fighter pilots with air refueling qualifications. This study tried to prevent hazard in advance by discriminating the risk factors according to the human factors related to the fighter pilot during the air refueling mission.

Contents and Issues of the Draft Legislation of Part VI the Carriage by Air of Korean Commercial Code in Respect of the Carriage of Cargo by Air (항공화물운송에 관한 상법 항공운송편 제정안의 내용 및 쟁점)

  • Lee, Kang-Bin
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.43
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    • pp.201-238
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    • 2009
  • The purpose of this paper is to describe the contents and issues of the draft legislation of Part VI the Carriage by Air of Korean Commercial Code in respect of the domestic carriage of cargo by air, comparing to the related provisions of the Montreal Convention of 1999 for the unification of certain rules for international carriage by air and the related provisions of Korean Commercial Code in respect of the carriage by land and sea. The Montreal Convention in respect of the international carriage by air was adopted in 1999, and Korea has ratified the Montreal Convention in 2007. However, there is now no national legislation in respect of the carriage by air in Korea. Thus, the Ministry of Justice has prepared the draft legislation of Part VI the Carriage by Air of the Korean Commercial Code in July 2008, and the draft legislation is now being reviewed by the National Assembly. The draft provisions of Part VI the Carriage by Air are basically adopting most of the related provisions of the Montreal Convention in respect of the carriage of cargo by air and some draft provisions are applying the related provisions of the Korean Commercial Code in respect of the carriage of cargo by land and sea. In respect of the carriage of cargo by air, the contents of the draft legislation of Part VI the Carriage by Air are composed of the provisions in respect of the liability of the carrier, the rights of the consignor and consignee, the transport document and others. In respect of the carriage of cargo by air, the issues on the draft legislation of Part VI the Carriage by Air are the problems with respect to the extinguishment of the liability of the carrier, the application for the non-contractual claim, the liability limit of the servants or agents of the carrier, the right of disposition of cargo, the effect of breach of the provision in respect of the air transport document, the prescription of claim of the carrier, the immunity reasons from liability of the carrier for the loss or damage of the cargo, the making out of the air waybill, and the effect of the statement of the air transport document. In conclusion, the national legislation of Part VI the Carriage by Air of the Korean Commercial Code will protect the right and interest of the consignor and consignee, and clarify the right and duty of the parties to the air transport. Also it will contribute to the development of the air transport industry in Korea.

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