• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.6
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• pp.27-36
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• 2002

The objective of this study is to improve the quality of the atmospheric environment by incorporating the factors of meteorology and urban climate into the field of urban and environmental planning. To this end, we have conducted a study on CLIMATOP and the mapping of urban climate, which are basic data used to analyze changes in climatic factors and the stagnation and accumulation of air pollutants. In particular, we focused on understanding the formation and movement of cold fresh air and its influx into urban areas by measuring and analyzing climatic factors. As a study result, classification criteria far CLIMATOP and a urban climatic map were made. In addition, we analyzed a digital elevation model, climatic data, and isothermal curves. As a result, we identified the corridor through which cold fresh air moves. We also observed that the temperature of the fluxed cold fresh air increased as land use changed. When the results of this study are applied to urban re-development and re-building projects, which require preliminary environmental assessment and environmental impact assessment, the practice proposed by this study is expected to contribute to the natural purification of air pollution activating the movement of cold fresh air and its influx into urban areas.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.3
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• pp.58-73
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• 2003

It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

• Food Science and Preservation
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• v.23 no.7
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• pp.1018-1025
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• 2016

To investigate biological activities in Aronia melanocarpa various drying methods were employed such as vacuum freeze drying, hot air drying and cold air drying. DPPH radical scavenging activity and ABTS radical scavenging activity of vacuum freeze dried Aronia melanocarpa was higher than hot and cold air dried Aronia melanocarpa. Vacuum freeze drying method showed the greatest contents of total phenol (15.34 g GAE/100 g), flavonoid (3.10 g GE/100 g) and tannin (2.46 g TE/100 g). Total anthocyanin content decreased to 163.52 mg C3G/100 g and 50.15 mg C3G/100 g for hot and cold air drying, respectively. Vacuum freeze-dried method increased the total anthocyanin content (743.09 mg C3G/100 g) when compared with fresh Aronia melanocarpa (163.52 mg C3G/100 g). Total proanthocyanidin content of vacuum freeze dried Aronia melanocarpa has increased to 6.21 g CE/100 g more than eight times compared with fresh Aronia melanocarpa (0.71 g CE/100 g). Chlorogenic acid and neochlorogenic acid content of vacuum freeze dried Aronia melanocarpa were higher than hot air dried and cold air dried Aronia melanocarpa, increasing about three times compared with fresh Aronia melanocarpa. These results suggested that vacuum freeze drying is optimal drying method to enhance biological activities in Aronia melanocarpa.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.2
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• pp.75-79
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• 2005

With three kinds of agricultural products such as perilla leaves, this research is focussed on how to keep a freshness of agricultural products during long time transport by sea. In case of export fresh agricultural products by sea, research on products loading method onto the pallet is very important factor for keeping effective cold air circulation inside the freezing marine container. Details are as follows: Clear examination of palletization for cold air ventilation inside the container. Optimization of package dimension for best loading efficiency onto the standard pallet. Best layout of palletized products inside the container. Research for the change of circumstance and product quality inside the pack.

• Journal of the Korean Institute of Gas
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• v.14 no.6
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• pp.27-30
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• 2010

This paper presents the system design process of district community cooling system using LNG cold energy. The newly developed LNG cooling system includes several heat exchangers, LNG storage tank, thermal mass storage tank, several cold energy storage tanks, gas air-conditioners, compressors, constant pressure regulators, cold energy and hot energy supply pipes. In addition, the gas air-conditioner system is installed to supply not sufficient cold energy due to low level of city gas consumptions during a summer period. This system design is very effective and safe to supply cold energy mass of fresh air by exchanging two thermal masses of an air and 200kcal/kg cold energy of LNG. The district community cooling system with LNG cold energy does not produce CO2 and freon gases in the air.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.1-6
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• 2000

Improvement of cold-tolerance of Italian ryegrass(Lo1ium multiflorum L.) is an important breeding objectivefor enlargement of cultivation area in Korea. To develop the cold-tolerant variety of Italian ryegrass,cold-tolerant clones survived under - 13- - 14$^{\circ}$C of minimum average air temperature in January wereselected in the area of Dun Nae, Kwangwon Province. The 5 lines of Italian ryegrass clones selected werepolycrossed for seed production. Synthetic seeds were examined on growth characters and forage productionsin Suwon from 1996 to 1998, in Unbong 1997 and in Younchun 1998, respectively. The growth charactersand forage productions of Italian ryegrass variety named as "Hwasan 101" were summarized as follow ;ltalian ryegrass variety, Hwasan 101 was tetraploid and showed semi-prostrate growth habit in autumn andwas not only dark green in leaf color and broad in flag leaf width but also excellent in leafiness. Also, itshowed low plant height at first heading date of 20th May and excellent lodging tolerance. Expecially,Hwasan 101 in all trial regions was 80 -90% of winter survivals that was higher than 60 -90% of Florida80 and Marshall varieties. Therefore we estimate that Hwasan 101 can be cultivated in regions that is higherthan -9$^{\circ}$C in minimum average air temperature and lower than 400m in sea level. In forage production ofHwasan 101, fresh weight and total digestible nutrient(TDN) yield were 66,940 and 6,551kghq and drymatter yield was 10,050kgha. In conclusion, Italian ryegrass, Hwasan 101 was medium and late maturingvariety but excellent in cold-tolerance, lodging-tolerance, leafiness, and forage production.(Key words : Italian ryegrass, Cold tolerance, New variety)ian ryegrass, Cold tolerance, New variety)

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.611-617
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• 2008

Nowadays Plate Heat Exchanger (PHE) is widely used in different industries such as chemical, food and pharmaceutical process and refrigeration due to the efficient heat transfer performance, extreme compact design and efficient use of the construction material. In present study, discussed main conception of plate heat exchanger and applied in vacuum. PHE and aimed apply in the fresh water generator which installed in ship to desalinate seawater to fresh water use heat from engines. The experiment is proceeded to investigate the heat transfer between cold and hot fluid stream at different flow rate and supply temperature of hot fluid. Generated fresh water as outcome of the system. PHE is an important part of a condensing or evaporating system. One of common assumptions in basic heat exchanger design theory is that fluid is to be distributed uniformly at the inlet of each fluid side and throughout the core. However, in practice, flow mal-distribution is more common and can significantly reduce the heat exchanger performance. The flow and heat transfer are simulated by the k-$\varepsilon$ standard turbulence model. Moreover, the simulation contacted flow maldistribution in a PHE with 6 channels.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.114-127
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• 2010

The purpose of this study is to find out cold and fresh air producing areas using climate-ecological functions in Changwon city, Gyeongsangnam-do, South Korea. The evaluation of climate-ecological functions were composed of the six factors: patch size with cold air generation and inflow functions, farmland and grassland ratio, mean slope degree, cross section types, mean slope length and roughness of bottom in valley. The analysis results of each evaluation factor in the study area were divided into 5 grades according to the capacity of cold air generation. The first-grade area with the highest factor values for cold air generation was take up 3.51% of the total study area, second grade was 13.48%, third grade was 31.65%, fourth grade was 27.28%, and fifth grade was 24.09%. According to the spatial distribution of cold air producing areas, the valleys around Mt. Bongnim, Changwon tunnel, and Anmin tunnel had higher evaluation grade. It will require the future research to establish the climate-ecological conservation areas and to construct the wind corridor based on the long-term microclimatic monitoring.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.253-256
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• 2006

This paper shows the study on application of the law temperature energy in the deep seawater. Deep, cold seawater has long been recognized as a valuable ocean energy resource. Recently, research and experimentation has been conducted on energy systems using deep seawater: deep seawater air conditioning system, ice-making device, salt and fresh-water manufacturing system and the Spray freeze drying system for extracting valuable material of the deep seawater. They are technically and economically feasible today: once installed, the energy is inexhaustible and there are no adverse environmental impacts. Because of the economy of scale in the air conditioning system, the seawater A/C system is most appropriate for supplying multiple buildings or hotels in a coastal area.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.4
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• pp.24-38
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• 2019

Due to the dramatic spatial changes caused by industrialization, environmental problems such as air pollution and urban heat island phenomenon, etc. are occurring in cities. In this case, the wind corridor, which is a passage through which fresh and cool air generated in forests outside cities move to the downtown, can be used as a spatial planning method for improving urban environmental problems. Cold air is determined by the characteristics of the flow depending on the topography and land use of cities, and based on this, the medium- and long-term plan should be established. Therefore, this study analyzed the flow of cold air at night through the KLAM_21 model in Suwon-si, Gyeonggi-do, to prepare the basic data required to apply the wind corridors. As a result, it turned out that cold air of Suwon-si was mainly generated from Gwanggyo Mountain that is a large mountain area in the north, and flowed into the urbanization promotion area, and about three hours after sunset, cold air flowed into the downtown. By district, the depth, wind speed, and direction of the cold air layer were formed differently according to the characteristics of the topography and land use. In the areas where large forests were adjacent, the flow of cold air was active. There are three main wind corridors where cold air flows to the downtown of Suwon-si, all of which are formed around rivers. Especially, if the connection between rivers and the surrounding green areas is high, the effect of wind corridors is found to be significant. In order to utilize the wind corridors of Suwon-si, based on the results of this study, it is necessary to make climate maps through actual survey and complex analysis of cold air flow and establish mid-to-long-term plans for the conservation and expansion of major wind corridors.