• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.9 no.4
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• pp.1-7
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• 2013

This study is to compare energy consumption of air-source, ground-source and dual-source heat pump systems during intermediate season using dynamic simulation. Ground-source heat pump has higher COP than that of air-source but requires additional power consumption of auxiliary equipment such as circulation pump. During intermediate season when the outdoor air temperature is favorable, total COP of air-source heat pump may be greater than that of ground-source when circulation pump power consumption is included. Dual-source heat pump which selects the more favorable heat source is compared with air-source only and ground-source only heat pumps for total power consumption. Results show that power consumption of dual-source heat pump is lower than that of ground-source only by 0.73%.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.7
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• pp.386-391
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• 2013

The dynamic characteristics of both raw-water source and air source heat pump utilized in water treatment facilities were investigated by using TRNSYS simulator. The modeling of the raw water source heat pump was verified by the measured data at the Cheongju water treatment facility, and the modeling at the air source heat pump was verified by the data from the Siheung water treatment facility. The average heating and cooling COPs from the raw-water source heat pump were higher than those of the air source heat pump by 19% and 18%, respectively. The power consumptions of the air source heat pump for the cooling and the heating were higher than those of the raw water source heat pump by 28% and 26%, respectively.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.23-34
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• 2003

Urban air quality is usually worse than that of rural counterpart. The contrasting atmospheric properties seem to be direct result of different urban-rural air pollutant emission. Hence, the emission estimation of air pollutants plays an important role to the atmospheric environmental management. The main purpose of this study is to find out the temporal and spatial distribution of air pollutant emission in Daegu area. For the study, the Daegu statistical yearbook and data of waste facilities and the report on traffic survey issued by Daegu metropolitan city and the statistical yearbook on the road capacity issued by the ministry of construction and transportation are used. Each item for the emission estimation is $SO_2$, CO, HC, $NO_x$, PM-10 from point, line and area source. The result were as follow; (1) The air pollutants with the highest amount of emission from the emission source is CO followed by $NO_x$, $SO_2$, PM-10, HC in descending order of magnitude. (2) The annually totaled air pollutant emission consists of 81%(73,185 ton/year) of line, 11%(9,589% ton/year) of area and 8%(7,445 ton/year) of point source in Daegu. Air polluant emission was mainly due to line sources. (3) High-emission of the air pollutants of line source appeared ariond Bukgu, Dalseonggun, Dongu and Seogu ; the areas with highway networks.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.324-329
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• 2003

An air-conditioner has various noise sources such as cooling fan noise, pumping noise, flow noise and impact noise. Among these, impact noise is the most unpleasant source. This is because the noise is produced in indoor unit of air-conditioner. To control the noise source effectively, first we must identify the noise sources. When we identify impact noise source, the measurement have to be carried out simultaneously. So we use beamforming method that requires less measurement points than intensity method and acoustic holography. The objective of this paper is to estimate the location of impact source. This objective can be achieved by using minimum variance cepstrum that is able to detect impulse embedded in noise. In this study, modified beamforming method based on cepstrum domain is proposed. Then this method applied to air-conditioner noise sources which produce impact noise.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.261-264
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• 2003

We try to distribute air pollution sources at target area. The complex method is used to distribute air pollution sources. Most of people, However, want to simple indicator as standard for express air pollution source. In many area, air pollution is caused by different types of sources. The general type is point source, such as tall stack of power plants and oil refineries stacks. A second type is areal source, such as local industry and transportation. In this aspect, the ratio of sulfur dioxide to nitrogen oxides (RSN =SO$_2$/NOx)is an indicator of air pollution source. the role of this ratio is to show the characteristics at target area of the relationship the point and the areal source. (omitted)

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.6
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• pp.719-731
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• 2003

In order to maintain and manage ambient air quality, it is necessary to identify sources and to apportion its sources for ambient particulate matters. The receptor methods were one of the statistical methods to achieve reasonable air pollution strategies. Also, receptor methods, a field of chemometrics, is based on manifold applied statistics and is a statistical methodology that analyzes the physicochemical properties of gaseous and particulate pollutant on various atmospheric receptors, identifies the sources of air pollutants, and quantifies the apportionment of the sources to the receptors. The objective of this study was 1) after obtaining results from the PMF modeling, the existing sources of air at the study area were qualitatively identified and the contributions of each source were quantitatively estimated as well. 2) finally efficient air pollution management and control strategies of each source were suggested. The PMF model was intensively applied to estimate the quantitative contribution of air pollution sources based on the chemical information (128 samples and 25 chemical species). Through a case study of the PMF modeling for the PM-10 aerosols, the total of 11 factors were determined. The multiple linear regression analysis between the observed PM-10 mass concentration and the estimated G matrix had been performed following the FPEAK test. Finally the regression analysis provided quantitative source contributions (scaled G matrix) and source profiles (scaled F matrix). The results of the PMF modeling showed that the sources were apportioned by secondary aerosol related source 28.8 ％, soil related source 16.8％, waste incineration source 11.5%, field burning source 11.0%, fossil fuel combustion source 10%, industry related source 8.3％, motor vehicle source 7.9%, oil/coal combustion source 4.4％, non-ferrous metal source 0.3％. and aged sea- salt source 0.2％, respectively.

• Journal of environmental and Sanitary engineering
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• v.17 no.2
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• pp.18-25
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• 2002

The comparison of the air quality with the evaluation of the environmental assessment before and after operations of the heat source and of the flue-gas desulfurization facilities were studied. First of all, several sites were selected for the representative sample points, and then they were examined air quality of the surroundings. The results were that TSP(total suspended particulate) analysis after an operation of the heat source facility was $74~81{\mu}g/m^3$, PM-10 was $31~94{\mu}g/m^3$, and $SO_2$concentration was 0.002~0.009ppm, respectively. As the result of examination to the concentrations of diffused pollutants, there was no relations between TSP concentration of sample points and the effect of air quality according to the heating source. When we compared the neighbored area of the heating source with the other area, the concentration of air pollutants after an operation of the facility of the heating source was similar to the heating source, the neighbored area, and the other area. So we concluded that there was no the effect of the air pollution by producted pollutants from the heating source.

• Journal of Environmental Science International
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• v.8 no.1
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• pp.135-144
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• 1999

Air quality modeling about coastal urban region such as Pusan shoud be consider shipping source emmited from ships anchoraging and running. It has been proved at our previous studies that the ratios of air pollutants emission amount in coastal area to inland are 12.2% for NO$_2$ and 11.7% for $SO_2$ and the air qualify of coastal urban area consierably counts on ships. Also the dispersion pattern of the all pollutants followed local circulation system in this region. Therefore this study has been developed air quality model which can describe the formation, transport, transformation and deposition processes of air pollutants considering shipping source. Currently, restriction for emission amount of ships does not exist, so our study will be useful to set the omission standard and for devising air quality policy in coastal urban region.

• Tribology and Lubricants
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• v.17 no.5
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• pp.365-372
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• 2001

This paper has been presented the hydrodynamic effect by the journal speed, eccentricity and source positions in order to overcome the defects of air bearing such as low stiffness and damping coefficient. Choosing the two row source position of air bearing is different from existed investigations in the side of pressure distribution of air film because of the high speed of journal and the wedge effects by the eccentricity. These optimal chooses of the two row source positions enable us to improve the performance of the film reaction force and loading force as making the high speed spindle. In this paper, The pressure behavior in theory of air film according to the eccentricity of journal and the source positions analyzed. The results of investigated characteristics may be applied to precision devices like ultra-precision grinding machine and ultra high speed milling.

• Tribology and Lubricants
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• v.17 no.6
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• pp.476-481
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• 2001

This paper has been presented the hydrodynamic effect by the journal speed, eccentricity and source positions in order to overcome the defects of air bearing such as low stiffness and damping coefficient. Choosing the two row source position of air bearing is different from existed investigations in the side of pressure distribution of air film because of the high speed of journal and the wedge effects by the eccentricity. These optimal chooses of the two row source positions enable us to improve the performance of the film reaction force and loading force as making the high speed spindle. In this paper, The pressure behavior in theory of air film according to the eccentricity of journal and the source positions analyzed. The theoretical analysis have been identified by experiments. The results of investigated characteristics may be applied to precision devices like ultra-precision grinding machine and ultra high speed milling.