• Title/Summary/Keyword: conditioning factor

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A Study on Area Planning of Air Conditioning Room for Hospital Design Focused on System (체계중심병원설계를 위한 공조실 면적 계획에 관한 연구)

  • Kim, Eun Seok;Yang, Nae Won
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.25 no.4
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    • pp.27-35
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    • 2019
  • Purpose: As the improvement in quality of medical environment and the spatial consideration for the prevention of infection in the hospital have become increasingly important in the recent years, specific and practical planning for air conditioning room's area has become a major issue accordingly. However, the air conditioning room tends to be discussed focusing on technical factors such as air conditioning systems that are irrelevant to building plans, while discussions of most departments related to the medical functions have actively taken placed. Therefore, this study aims to investigate the factors influencing the planning for the air conditioning room area, and through subsequent analysis of the area of the air conditioning room, to propose a way to improve effective planning for the air conditioning room area. Methods: This study examines the case hospitals that fall into two types: each floor supply system and concentrated supply system, and compares and analyzes the air conditioning room area-related factors and the characteristics of changes in the interior of air conditioning room before and after remodeling through air conditioning floor plan of those case hospitals. Results: The air conditioning room can be classified into the net area of the functional space such as duct passages, and the public area such as aisle space, and of those the public area is an important factor in calculating the area of the air conditioning room. The public area of the air-conditioning room should not be planned considering only the spaces for mobile passage or maintenance activities, but should be planned taking into account internal changes such as expansion and replacement of equipment in the future from the beginning. Implications: When planning a medical facility, it is used as basic data for the planning of the air conditioning room area, which is a significant fixed factor in the initial setting.

High-Efficiency Power Conditioning System for Grid-Connected Photovoltaic Modules

  • Choi, Woo-Young;Choi, Jae-Yeon
    • Journal of Power Electronics
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    • v.11 no.4
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    • pp.561-567
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    • 2011
  • This paper presents a high-efficiency power conditioning system (PCS) for grid-connected photovoltaic (PV) modules. The proposed PCS consists of a step-up DC-DC converter and a single-phase DC-AC inverter for the grid-connected PV modules. A soft-switching step-up DC-DC converter is proposed to generate a high DC-link voltage from the low PV module voltage with a high-efficiency. A DC-link voltage controller is presented for constant DC-link voltage regulation. A half-bridge inverter is used for the single-phase DC-AC inverter for grid connection. A grid current controller is suggested to supply PV electrical power to the power grid with a unity power factor. Experimental results are obtained from a 180 W grid-connected PV module system using the proposed PCS. The proposed PCS achieves a high power efficiency of 93.0 % with an unity power factor for a 60 Hz / 120 Vrms AC power grid.

Optimization of Convective Trapezoidal Profile Fin having Fluid inside the Wall (내벽에 유체가 있는 대류 사다리꼴 형상 Fin의 최적화)

  • Jeong Byung-Cheol;Lee Sung-Joo;Yoon Sea-Chang;Kang Hyung Suk
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.2
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    • pp.95-102
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    • 2006
  • This study analyzes and optimizes a design for a trapezoidal profile straight fin using one-dimensional analytical method. The heat transfer, fin length and fin height are optimized as a function of fin volume, fin shape factor and fin base length. In this optimization, convection characteristic number over fin surface and that of fluid inside fin wall are considered. One of the results shows that the maximum heat loss increases as fin volume increases and both fin shape factor and fin base length decrease.

The Characteristics of a Bypass Air Conditioning System for Load Variation (부하변동에 대한 바이패스 공조시스템의 특성)

  • 김보철;신현준;김정엽
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.3
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    • pp.240-246
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    • 2002
  • Bypass air conditioning systems are divided into three types; an outdoor air bypass, a mixed air bypass and a return air bypass system. What makes the return air by pass system more effective is that it directs all of moist outdoor air through the cooling coil. The bypass air conditioning system can maintain indoor R.H (Relative Humidity) less than a conventional CAV (Constant Air Volume) air conditioning system by adjusting face and bypass dampers at part load. When a design sensible load (the ratio of sensible load to total sensible load) is 70 percent (at this time, RSHF (Room Sensible Heat Factor) . 0.7), indoor R.H was maintained 59 percent by the return air bypass system, but 65 percent by the conventional CAV air conditioning system (valve control system). The bypass air conditioning system can also improve IAQ (Indoor Air Quality) in many buildings where the number of air change is high.

우리나라에서의 증발식 냉각의 효용성

  • Min, Man-Gi
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.3 no.3
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    • pp.199-208
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    • 1974
  • The effectiveness with which evaporative cooling can be used in Korea was analysed by making use of weather data of 15cities in a past decade. In ASHRAE comfort chart for a still air atmospheric condition was divided into two dimensional array, 14 zones by effective temperature and 10 zones by relative humidity, and all hours of weather condition in those zones were. computed from every 4 hours weather data in a past decade. From this computation obtained were for 15 cities : 1. average annual total hours above $23^{\circ}C$ ET 2. effective temperatures with $5\%$ excess factor, and 3. ratios of all hours in wet (above $25.6^{\circ}C$ WBT), intermediate $(22^{\circ}C\;to\;25.6^{\circ}C\;WBT)$, and dry $(below\;22^{\circ}C\;WBT)$ area to total hours in whole area on comfort chart beyond $23^{\circ}C$ ET to effective temperature of $5\%$ excess factor. It was shown from this computational result that in Korea evaporative cooling was not effective for building and residential comfort air conditioning but could be useful for comfort air conditioning in industry and industrial air conditioning, depending upon the air stream velocity and the type of application.

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A Study on the Asymmetry Factor in Photophoresis (광영동에 있어서의 비대칭인자에 대한 연구)

  • Park, S.H.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.694-702
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    • 1995
  • When a small absorbing particle is exposed to a strong thermal radiation incidence, it moves towards or away from the radiation source due to the nonuniform internal absorption of the radiation. It is called the photophoretic phenomena and governed by the asymmetry factor. An asymmetry factor for the total wavelength range is calculated to estimate the photophoretic phenomena of a particle in a combustor or in the atmosphere and compared to that for a single wavelength. The samples are soot particulates, water droplets, ice particles, silicon particles, $SiO_2$ particles, aluminium oxide particles, whose spectral complex refractive index are available. Although differences between total and monochromatic asymmertry factors are not much for relatively uniform distribution of the spectral refractive index, they are great in general. Therefore the use of the monochromatic factor will considerably deteriorate the accuracy of the calculation of the photophoresis.

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Analysis of Saving Rates according to Energy Consumption Factors in Office Building (사무소 건물의 에너지 소비 요소별 절감률 분석)

  • Park, Byung-Il;Yang, In-Ho
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.28 no.3
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    • pp.115-122
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    • 2016
  • In this study, 21 energy reduction factors were selected as architecture, system & operation, and lighting and equipment parts to analyze reduction method of the load occurring in office buildings. Energy consumption simulation was performed. In the architecture part, saving rate (1.53%) of "occupant density" factor was the most efficient. In the system and operation part, saving rate (1.28%) of "interior VAV and exterior FPU type" factor was the most efficient. In case of lighting and equipment part, saving rate (12.42%) of "schedule" factor was the most efficient. In the three parts, saving rate of the lighting and equipment part was 27.32%. This was caused by the "schedule" factor. Saving rates of the architecture part and the system and operation part were 3.39% and 1.20%, respectively.

Monthly Average Insolation Data on South-Facing Inclined Surfaces (남향경사면의 월평균 전일사량)

  • Kim, Doo-Chun
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.8 no.4
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    • pp.254-259
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    • 1979
  • Radiation data on south-facing surfaces required for the simplified design pro cedures for solar energy systems, have been computed using the method by Liu and Jordan. For the five localities of South Korea selected from reference 6, the factor R for the conversion of the monthly average daily total radiation on a horizontal surface to that on an inclined surface is presented in Table 5. For the other localities, the convession factor R can by computed using Table 2 through Table 4.

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Innovative and practical conditioning beverages for public health and athletic performance: Focus on immunopotentiation by lactic acid bacteria B240

  • Lee, Minchul;Kim, Kyunghee
    • Korean Journal of Exercise Nutrition
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    • v.23 no.2
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    • pp.13-15
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    • 2019
  • [Purpose] Functional beverages are a protective or enhancing factor influencing not only public health but also athletic performance. The purpose of this study was to highlight the new conditioning beverage of the Lactobacillus pentosus strain b240 (B240) with electrolytes or proteins, which strengthens immune functions to improve the quality of life. [Methods] ISeveral related studies systematically reviews three main issues associated with conditioning beverages: (a) utilization and availability of the functional beverage; (b) significance of B240 in immune strengthening; and (c) availability and application of conditioning drinks in the daily life and sports field. [Results] Intake of B240 led to greater enhancements, including blood T-helper, NK cell, IgA and IgG level in conjunction with strengthen immune functions. These results speculated that the practical application of B240 contained beverages on physiological health and performance. [Conclusion] BODYMAINTÉ, this novel conditioning beverage is expected biological utility responsible for improved sports performance as a functional drink and has potential health-related implications.