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A Study on the Simplified Presumption Method for the Prediction of Cooling and Heating Performance in a Fresh Air Load Reduction System by Using Geothermal Energy (지열 이용 외기부하 저감시스템의 냉각 및 가열효과 예측 간이추정법에 관한 연구)

  • Son, Won-Tug;Choi, Young-Sik
    • Journal of the Korean Society of Industry Convergence
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    • v.13 no.3
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    • pp.169-181
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    • 2010
  • This paper presents a feasibility study of a fresh air load reduction system by using an underground double floor space. The fresh air is introduced into the double slab space and passes through the opening bored into the footing beam. The air is cooled by the heat exchange with the inside surface of the double slab space in summer, and heated in winter. This system not only reduces sensible heat load of the fresh air by heat exchange with earth but also reduces latent heat load of the fresh air by ad/de-sorption of underground double slab concrete. In this paper, we proposed a simplified presumption method for the prediction of cooling and heating performance in the system. In conclusion the proposed method has been verified by comparing with the calculated value of the numerical analysis model by using nonlinear two-dimension hygroscopic question.

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Electrochemical Behavior and Differential Pulse Polarographic Determination of Piperacillin Sodium

  • Hahn, Young-hee;Son, Ean-ji
    • Archives of Pharmacal Research
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    • v.23 no.3
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    • pp.197-201
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    • 2000
  • In an aqueous piperacillin sodium solution, a well-defined single wave or single peak was observed by direct current(DC) polarography or differential pulse polarography(DPP). The peak potential change per pH unit was -54 mV in the phosphate buffer at $18^{\circ}C$, which indicated that protons were involved in the electrochemical reduction of the 2,3-dioxopiperazine moiety of piperacillin sodium with a $H^{+}e^{-}$ ratio of one. Using a phosphate buffer of pH 4.3, the $1.0{times}10^{-7}$ M piperacillin sodium single peak could be determined by DPP with relative standard deviation of 1.6 %(n=3). Piperacillin sodium could be analyzed with-out interference from penicillin G-potassium, which enabled the employment of DPP as a fast and simple technique for monitoring the synthetic process of the antibiotic.

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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.

Study on Effect of Wave Control by Multi-Cylinder Piles Using Delft-3D Hydrodynamic Model (Delft-3D Model을 이용한 다원주 군파일의 파랑제어 효과에 관한 연구)

  • Lee, Snag-Hwa;Jang, Ean-Chul;Lee, Han-Seung;Jeong, Seok-Jae
    • Journal of Ocean Engineering and Technology
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    • v.25 no.2
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    • pp.29-35
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    • 2011
  • In order to effectively control waves in a coastal zone, Multi-Cylinder Piles have been suggested as economic structures. A numerical analysis was conducted using the Delft-3D: WAVE module based on SWAN, which considered wave shoaling and refraction. Moreover, irregular waves were used to investigate the hydrodynamic characteristics of the wave interaction with the structure. In this paper, a numerical analysis was carried out to research the effect of wave control through a wave height analysis concerning an existing, concrete wave breaker and multi-cylinder piles placed at the same location. As a result, the effect of the wave control is shown using the wave breaker, multi-cylinder piles, and existing data.

A Study on the Operation of Disaster Management Using Cadastral Data and Organizational Structure (지적자료와 조직을 활용한 재난관리 운영방안에 관한 연구)

  • Park, Jong-Cheul
    • Journal of Cadastre & Land InformatiX
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    • v.46 no.2
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    • pp.79-92
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    • 2016
  • The development to the high quality of life society requirers not only economic development but also high level of capacity in disaster management which can address the disaster promptly and ready for man made disaster such as fires, traffic accidents, stopping the function of infrastructure in energy and telecommunication sectors. In this research a disaster management system which utilize cadastral data and cadastral sturcure has been p roposed a s a m ean o f enhancement of disaster management capacity. It is expected that to make use of all cadastral information in every disaster management steps, disaster risk information will be calculated and provided by parcel unite and the cadastral organization will participate to disaster management utilizing cadastral organization's nation wide structural network and skilled manpower by adopting parcel-based disaster management system.

A Numerical Study on Sectional Temperature Distribution and Heat Recovery Amount of Passive Ventilation Skin (패시브환기외피의 단면온도분포 및 열회수량에 관한 수치해석적 연구)

  • Lee, Tae-Cheol;Son, Yu-Nam;Yoon, Seong-Hwan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.10
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    • pp.705-710
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    • 2012
  • This study aims to analyse changes of inner temperature of PVS(Passive ventilation skin) and heat recovery when it has ventilation of air through PVS using numerical simulation in the winter condition. Results are as follows. 1) In case of the air inflows through PVS, change of inner temperature of PVS is lower than in case of the air flows inner space to out space, by dynamic insulation. 2) It was identified that the temperature gradient of PVS were bigger by increases of ventilation amount. To reduce ventilation load, heat transfer efficiency at the inner side of PVS is important and what performance of insulation at the inner side of PVS secure helps to improve heat performance of all PVS.

Effect of Acupuncture and Moxibustion at SP6(Sanyinjiao) and BL28(Pangguangshu) on Experimental Acute renal failure in rats (삼음교(三陰交)(SP6), 방광유(膀胱兪)(BL28)의 침자 및 애구자극이 흰쥐의 실험적 급성신부전에 미치는 영향)

  • Kim, Min-ho;Park, Chun-ha;Kim, Hyo-ean;Yun, Yeo-chung
    • Journal of Acupuncture Research
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    • v.19 no.6
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    • pp.49-60
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    • 2002
  • Objective : The aim of this experiment is to investigate the effect of acupuncture and moxibustion at SP6(Sanyinjiao) and BL28(Pangguanshu) on uranyl acetate-induced acute renal failure in rats. Methods : To induce experimental acute renal failure, uranyl acetate was intraperitoneally injected to rats by 5mg/kg. 3 days later acupuncture and moxibustion treatment was done at SP6(Sanyinjiao) and BL28(Pangguanshu) bilaterally of the rats. And then 4 days later, we measured rats' body weight, kidney weight, serum BUN, creatinine and serum eletrolyte levels(Na, K and Cl). Results : In the moxibustion group, hypertrophy index of kidney and serum BUN level were decreased marginally significantly, and serum creatinine, K levels were decreased significantly. But in the acupuncture group, there was no significance at this experiment. Conclusions : SP6(Sanyinjiao) and BL28(Pangguanshu) moxibustion can decrease serum BUN, creatinine, and serum eletrolyte levels on uranyl acetate-induced acute renal failure in rats. And the study will be done continuously about non-effect in the acupuncture group at this experiment.

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The Effectiveness of Early Screening and Intervention for Children at Risk of Reading Underachievement

  • Park, Hyun Jeong;Bang, Hee Jeong;Nam, Min
    • Child Studies in Asia-Pacific Contexts
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    • v.4 no.1
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    • pp.47-63
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    • 2014
  • The purpose of this study was to develop a screening test for children at risk of reading underachievement and to investigate the effectiveness of the early-stage intervention program. In the first part of the study, we recruited 155 elementary first grade students for a screening test. Phonological deletion, digit naming, object naming, and sound-letter correspondence knowledge of a screening test, all assessed at the beginning of the school year, predicted the reading ability at the end of the school year. In the second part of the study, we analyzed the difference in the reading ability between fourteen children who participated in the intervention program and eighteen non-participating children. Reading ability was assessed by evaluating word recognition, oral reading fluency, reading comprehension, and pseudo-word recognition. The reading ability of intervention group improved more compared to control group, and the difference between two groups accentuated over time. However, final analysis conducted in November revealed that two groups did not differ significantly in oral reading fluency. This suggests that, unlike word recognition and comprehension, fluency might not dramatically improve in a short period.

The Binding of Human CLIC1 with SEDL and Its Characterization in vitro

  • Park, Jeong-Soon;Lee, Kyoung-Mi;Jeong, Mi-Suk;Jin, Gyoung-Ean;Jang, Se-Bok
    • Bulletin of the Korean Chemical Society
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    • v.28 no.4
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    • pp.574-580
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    • 2007
  • Full-length chloride intracellular channel protein 1 (CLIC1) is a member of the family of proteins related to bovine chloride intracellular channel p64. Mutations in the SEDL gene cause spondyloepiphyseal dysplasia tarda (SEDT), a rare X-linked chondrodysplasia. The link between the intracellular chloride channels and SEDL is an important step toward understanding their functional interplay. In the present study, CLIC1 protein was subcloned into the pGEX-KG vector and overexpressed in XL-1 blue cells. We developed a large-scale expression system composed of glutathione S-transferase (GST) fused with a 240-amino-acid CLIC1 protein in Escherichia coli. The soluble CLIC1 protein was successfully purified to homogeneity, and its purity, identity, activity and conformation were determined using SDS-PAGE, MALDI-MS, biophotometer and circular dichroism spectroscopic studies. The binding of both CLIC1 and SEDL proteins in vitro was detected by BIAcore biosensor and fluorescence measurements.

Analysis of the Initial Cost Payback Period on the Open-loop Geothermal System Using Two Wells (복수정을 이용한 개방형 지열 시스템의 초기투자비 회수기간 분석)

  • Cho, Jeong-Heum;Nam, Yujin
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.3
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    • pp.119-126
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    • 2017
  • Recently, ground source heat pump systems are being used in buildings for cooling and heating to reduce greenhouse gas and save energy. However, ground source heat pump systems mainly use the vertical closed-loop geothermal system design rather than the open-loop geothermal system design. This is due to a lack of knowledge and few research feasibility studies. In this research, a dynamic thermal analysis numerical simulation based on a standard house model was conducted for an open-loop geothermal system. Based on heating load analysis results, the life cycle costs of a standard house using an open two-well geothermal system were analyzed and compared with a vertical closed-loop geothermal system, and a diesel boiler. As a result, it was found that using an open two-well geothermal system shows economic return on investment after three years.