• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.109-120
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• 2001

Live load data were collected with a systematic manner from a survey of a refrigeration stores. Using the collected floor live load survey data, the basic statistics, a histogram of the uniformly distributed loads, and the equivalent uniformly distributed loads are computed for various structural members. Based on the above results, the maximum values of a combined live loads during the design life have been estimated and compared with current design live loads. The ultimate goals of this study are to develop probabilistic live load models to analyze survey data of domestic refrigeration stores, and to propose design live loads for structural types.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.7
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• pp.629-634
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• 2005

This paper performed to predict vertical temperature distribution and air flow near cold heat source in the mass merchandising store. At the height of 150 cm, the vertical air temperature difference between the results of CFD and of measurement field showed $10\%$ near the refrigeration zone and $8.8\%$ near the freezing zone. Therefore, it regarded as appropriate for the using CFD to investigate airflow near the heat sources. The 3 kinds of CFD model were divided by the disposition of diffuser/exhaust and diffuser air temperature. At the refrigeration and freezing zone in the Model 2 and 3, the temperature difference between the front and the back of human model were showed $6.8^{\circ}C\;and\;3.9^{\circ}C$ with diffuser air temperature $17^{\circ}C$ and were showed $6.8^{\circ}C$ and $4^{\circ}C$ with diffuser air temperature $19^{\circ}C$.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.11a
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• pp.45-49
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• 2001

To maintain the freshness of produce, because of stand away between produced and consumer, we need refrigeration system that can supply to consumer at cold chain as soon as gathering. General refrigeration system consist of refrigeration chamber or low temperature store. But the vacuum technology can rapidly refrigeration without refrigerator. This precool system possible to get low precooled temperature, suitable for the fishes, the meat, the vegetables, the fruit etc. Especially get advantage that quality maintain through rapid refrigeration of ferment directly generate heat. Vacuum precool system's principle is that water saturated temperature reduce according to pressure is get to vacuum area, so product temperature reduce as water evaporation at product. In vacuum suction, unit, on early experiment period run the rotary type vacuum pump at purpose pressure, then maintain pressure by water-diven ejector. As the results, cabbage took about 60 minutes to reach from $23.2^{\circ}C$ to $4.5^{\circ}C$at 5mgHg abs.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.1
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• pp.74-80
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• 2013

In this paper, we have proposed a vapor cycle refrigeration system as a cooling system to provide cooling air to the aircraft external reconnaissance stores. In the proposed vapor cycle system, receiver which prevents refrigerant from subcooling was eliminated and thermal expansion valve was replaced with electronic expansion valve. The vapor cycle refrigeration system is aimed to provide cooling air to the reconnaissance stores which is added to the aircraft in the form of external store. The wide temperature range of ambient air from the flight conditions can decrease the cooling performance and can make the refrigeration system unstable in low ambient temperature. Performance characteristics of the vapor cycle refrigeration system has been experimented under air conditions which is derived from the flight envelope. From the experiments, the vapor cycle refrigeration system has been proved to provide enough cooling air to the reconnaissance equipment and to be stable under all the flight conditions.

• Journal of the Korean Institute of Gas
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• v.10 no.1 s.30
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• pp.38-42
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• 2006

In this study, a simulation technology for refrigeration cycle which can liquefy and store liquified petroleum gas (LPG) using pure propane as a refrigerant has been introduced. Cooling water as the second cooling medium was used for the liquefaction of propane. Peng-Robinson equation of state was used for the entire refrigeration cycle. A new alpha formulation proposed by Twu et al. was used for the more accurate prediction of vapor pressures of pure propane component and LPG constituents. API method for the accurate estimation of liquid densities of propane and LPG was used instead of using Peng-Robinson equation of state. PRO/II with PROVISION release 7.1, a general purpose chemical process simulator was used for the simulation of the overall refrigeration system. Through this work, we can successfully simulate the real propane refrigeration plant operating at domestic site.

• Journal of Distribution Science
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• v.14 no.10
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• pp.153-164
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• 2016

Purpose - In general, large companies have larger organizations, funds, and systems to provide more effective and efficient services in the market. However, development needs to support the livelihood of ordinary citizens who work for small businesses as well. This research suggests that a new distribution channel, called a "foothold style Kosa mart," that cooperates jointly with a distribution center and a large discount mart can provide direct solutions to small and mid-size distributors. This new distribution channel can achieve a limited type of "Nadle shop (small supermarket) foster project" related to building a joint distribution center and improvement in wholesale supply. Research design, data, and methodology - Data about the Korea distribution situation, the Nadle stores, and the logistics centers were collected from literature, Statistics Korea, journals, and reports. Specifically, we investigated information about Kosa Mart and Nadle stores. We focused on the redesign of the distribution center for the Nadle store. Results - The Kosa Mart distribution center now includes 18 warehouses, and has been handling 2000-3000 items. Most of the warehouses have been simply designed and items loaded and stored without refrigeration; thus, it is possible to store only products of certain manufactured goods. The current logistics center has no wholesale function because it failed to resolve the joint purchasing and product supply issues of competitively priced products. Conclusions - This study aimed to identify ways to strengthen the competitiveness of small- and medium-sized retailers. A Kosa Mart redesign aims to unifying the logistics center, stores, and customers. First, the joint wholesale logistics system, equipped with an integrated ordering system, needs to process customer orders and store orders at the same time. Second, excellent small business product development has to connect with production. Third, the store composition needs to support a shipping hub. Fourth, the Mart differentiates itself from convenience store goods by supplying regional and specialized products to customers. Fifth, a service buying agent and direct transactions between producers and consumers need to be established, and exhibits and displays of goods need to be improved.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.583-590
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• 2008

최근 작업자 숙소 및 이송용 외에 작업용으로 사용 가능한 Barge선의 일종인 Accommodation Work Barge 선의 건조량이 증가 추세인 바 현재 중국에서 건조 중인 해당 선박의 HVAC & Refrigeration system에 대하여 정리하였다. 본 시스템은 R404A Direct expansion 냉각방식 (직접팽창방식)이 적용되었으며 HVAC system 중 Air conditioning 부분에 대해서는 선박의 각 Deck 기준으로 Zoning 하여 개별적인 Air handling unit와 Condensing unit를 구성하였으며 (각 unit의 용량은 필요용량의 100%), 냉동 창고의 Refrigeration system은 해당 격실 (육고, 어고, 야채고)에 각각 Unit cooler를 설치하고, Condensing unit를 기계실에 설치하였다. 장비는 전체 용량 100%에 대하여 항시 운전하는 100% 용량의 장비와 비상시에 운전하는 100% 용량의 예비 장비로 구성된다. 냉동 창고에 인접한 Dry provision store는 냉동 창고와는 별개로 중앙 공조기로부터의 냉각 공기를 이용하여 Spot cooling하였다. 본 System의 구성에 대한 장점 및 단점은 아래와 같다. 1. Air conditioning system이 각 Zone에 대하여 구성되므로 각 Zone에 대하여 제어가 가능하다. 2. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 냉매 배관의 길이가 짧다. 3. Air con. 실에 Air handling unit와 Condensing unit가 설치되므로 실내의 Maintenance space 상에 여유가 없다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.12
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• pp.1088-1094
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• 2003

Case study was peformed to analyze energy load for department stores and develop energy load model to be applied to a cogeneration system. Energy loads of 14 departments were analyzed based on energy load sheets written by operators and energy load of one department store was measured through modem communication for a year. Energy load of department stores shows various variations depending on when they are opened or closed and, hours, days and months. In this paper, the measurement was compared with data in energy load sheets and resolved, and energy load model for a department store was built. It is important to use an accurate energy load model for an accurate feasibility study applying a cogeneration system to buildings.

• International Journal of Air-Conditioning and Refrigeration
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• v.12 no.4
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• pp.169-175
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• 2004

Case study was performed to analyze energy load for department stores and develop energy load model to be applied to a cogeneration system. Energy loads of 14 depart­ments were analyzed based on energy load sheets written by operators and energy load of one department store was measured through modem communication for a year. Energy load of department stores showed various trends depending on when they were opened or closed, or by hour, day and month. In this paper, the measurement was compared with the data in energy load sheets and resolved, and energy load model for a department store was built. It is important to use an accurate energy load model for an accurate feasibility study applying a cogeneration system to buildings.

• The Journal of Korean Medicine
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• v.39 no.1
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• pp.22-34
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• 2018

Objectives: The purpose of this study is to investigate changes of the marker compounds and anti-inflammatory effect of Gamisoyo-san decoction (GMSYS) depending on storage temperature and periods. Methods: GMSYS was stored at room temperature or refrigeration for 12 months. According to storage temperature and periods, pH and sugar content of GMSYS were measured. To determine the marker compounds of GMSYS, high-performance liquid chromatography analysis was performed. To estimate the anti-inflammatory effect of GMSYS, LPS-induced pro-inflammatory mediators and cytokines were measured in RAW 264.7 cells. Results: There was no change in pH and sugar content depending on storage temperature and periods of GMSYS. The contents of gallic acid and mangiferin in both of room temperature and refrigerated decoctions reduced with increasing storage periods. Chlorogenic acid was time-dependently decreased in case of stored at room temperature. GMSYS significantly inhibited the LPS-induced production of nitric oxide, prostaglandin $E_2$ ($PGE_2$) and IL-6 in RAW 264.7 cells. These effects equally maintained up to 3 months at both of room temperature and refrigeration. Since 4 months, the inhibitory effect of GMSYS on LPS-induced $PGE_2$ production was time-dependently reduced, and the decrease in $PGE_2$ inhibitory effect of decoction stored at refrigeration was lower than that of stored at room temperature. Conclusions: Our results indicate that the anti-inflammatory effect of GMSYS are maintained up to 12 months, but it shows optimal efficacy up to 3 months. It is recommended to store in a refrigeration for short periods since some components decrease as storage periods becomes longer.