• Title/Summary/Keyword: progress function

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An Experimental Study on the Gas Productivity from Gas Hydrate (가스하이드레이트 생산성 분석에 관한 실험 연구)

  • Park, Seoung-Soo;Han, Jeong-Min;Kwon, Ok-Bae;Shin, Chang-Hoon;Lee, Jeong-Hwan
    • New & Renewable Energy
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    • v.2 no.3
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    • pp.37-41
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    • 2006
  • In this study, an experimental apparatus has been designed and set up to analyze the dissociating phenomena of hydrate in porous rock. Experiments with the depressurization scheme have been carried out to investigate the dissociation characteristics of methane hydrates and the productivities of dissociated gas and water. From the experiments, it has been provided a determination of volume of gas produced and the progress of the dissociation front, as a function of time when hydrate is depressurized. Also, it has been investigated the flowing behavior of the dissociated gas and water in porous rock and the efficiency of the production

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Progress in Transgenic Cloned Pig for Xenotransplantation

  • Park, Kwang-Wook
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2003.10a
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    • pp.9-19
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    • 2003
  • Pig organ is thought to be the most suitable nonhuman organ for xenotransplanstation. However, one of the major constraints to using pig organs for xenotransplantation is human natural antibody-mediated hyperacute rejection (HAR). Elimination of a(1,3) galactosyltransferase (GGTA1) from the pig is expected to be a solution to the problem of hyperacute rejection. ry1any efforts have made characterization of GGTA1 in structure and function. improvement in the technique of DNA transfection of somatic cells and advancement of the pig NT, a specific modification has been made to one copy of the GGTA1 gene by Missouri group in 2002. To date because homozygousity of the genetic modification has been achieved in this gene, the role of gala(1,3) gal specific natural antibody in HAR and the efficacy of xenotransplantation in a nonhuman primate model will be addressed. If other genes are found to be involved in rejection of pig donors by primates, the technology will be available to modify those genes so that rejection can be overcome.

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Change of FVC, $FEV_1$ after Discontinuance of Bronchodilator in Coal Workers' Pneumoconiosis Patients (탄광부진폐증 환자에서 기관지확장제 투여 중단 후의 노력성폐활량 및 일초폐활량의 변화)

  • Cheon, Yong-Hee
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.2 s.24
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    • pp.245-250
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    • 1988
  • For the evaluation of change of FVC and $FEV_1$ after discontinuance of bronchodilator in the coal workers' pneumoconiosis patients, 17 pairs of patients were selected. They were matched by the age(${\pm}5$ y.o.) and the type of ventilatory impairment. Pulmonary function was measured 2 times bimonthly before and after the drug discontinuance discontinued after measurement of PFT for 2 times. In case group the bronchodilator was discontinued after measurement of PFT for 2 times. In control group there was no interruption of medication. FVC, $FEV_1$ decreased in both group as measurement progress. Simple linear regression coefficients against the month of measurement were calculated in both group and tested for parallelism between two groups. The results of test revealed that both regression coefficients were parallel. So in conclusively, discontinuance of medication of bronchodilator for coal workers pneumoconiosis patients has no effect on the decreasing rate of FVC, $FEV_1$.

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Jc control of $Nb/A1_2O_3/Nb$ Josephson junction ($Nb/A1_2O_3/Nb$ 조셉슨 접합의 임계전류밀도 제어)

  • 김규태;홍현권;이규원
    • Progress in Superconductivity and Cryogenics
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    • v.4 no.1
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    • pp.1-3
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    • 2002
  • Single Josephson junctions, which are of cross type, of $50 ${\mu}{\textrm}{m}$ {\times} 50 ${\mu}{\textrm}{m}$$ were fabricated under several oxidation conditions to Investigate controllabilities of critical current density (Jc) with the standard KRISS processes. Considering that the self-field effect suppresses the observed critical current (Ice) at high Jc region, we could reasonably estimate Jc values from I-V observations. The dependence of the obtained Jc as a function of exposure, which is equal to pressure (P) times time (t), was well fitted to a curve of Jc ~ (Pt)-0.34. The maximum Jc value at the controllability margin was found to be 3 kA/cm$^2$with the current equipment set up.

Effects of Design Parameters on Performance of the Stirling Refrigerator

  • Hong, Yon-Ju;Park, Seong-Je;Kim, Hyo-Bong;Park, Young-Don
    • Progress in Superconductivity and Cryogenics
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    • v.6 no.2
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    • pp.35-39
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    • 2004
  • The split-type free displacer Stirling refrigerators have been widely used for the cooling of infrared sensors and HTS filters. The thermodynamic and electric performance of the Stirling refrigerator is depending on the design and operating parameters. In the Stirling refrigerator with a free displacer, the refrigeration power is a function of the pressure wave in the expansion space, dynamics of a displacer, driving frequency, and etc.. In this study, the analysis of the small Stirling refrigerator was performed to investigate the effects of design parameters on the cooling capacity. The results show the effects of charging pressure, driving frequency, cold end temperature, natural frequency of a displacer and volume of expansion space on the performance of the Stirling refrigerator.

Determination of winding diameter based on bending strain analysis for REBCO coated conductor tapes

  • Leon, M.B. De;Dedicatoria, M.J.;Shin, H.S.
    • Progress in Superconductivity and Cryogenics
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    • v.14 no.2
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    • pp.8-11
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    • 2012
  • In order to recognize the allowable bending diameter in coils, the strain as function of diameters is evaluated. The irreversible strain limits of $I_c$ in the easy and hard bending modes were measured. Strains were calculated at the coating film in the easy bending and at outer edge or inner edge in the hard bending of the CC tape, respectively. The tape geometry subjected to bending procedures is considered from the current industrial spool winding operation. Through the linear superposition of strain induced in different bending modes regarding the expressions, the appropriate design for critical bending diameter is suggested. Results proved that the existence of buckling resulting from bending in hard direction when applied strain exceeded 0.6% is possible. The depicted results showed that the strain limit as a viable parameter should be considered for future purposes.

Comparison of superconducting generator with 2G HTS and MgB2 wires

  • Park, S.I.;Kim, J.H.;Le, T.D.;Kim, H.M.
    • Progress in Superconductivity and Cryogenics
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    • v.15 no.4
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    • pp.48-52
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    • 2013
  • This paper compares the features of second generation (2G) High Temperature Superconducting (HTS) field coil with those of magnesium diboride ($MgB_2$) field coil for a 10 MW class superconducting generator. Both coils can function effectively in their respective magnetic flux density range: 10-12 T for 2G HTS field coil, 2 T for $MgB_2$ superconducting field coil. Even though some leading researchers have been developing 10 MW class superconducting generator with 2G HTS field coil, other research groups have begun to focus on $MgB_2$ wire, which is more economical and suitable for mass production. However 2G HTS wire is still appealing in functions such as in-field property and critical temperature, it shows higher in-field property and critical temperature than $MgB_2$ wire.

Optimization approach of insulation thickness of non-vacuum cryogenic storage tank

  • MZAD, Hocine;HAOUAM, Abdallah
    • Progress in Superconductivity and Cryogenics
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    • v.22 no.1
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    • pp.17-23
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    • 2020
  • Cryogenic insulation systems, with proper materials selection and execution, can offer the highest levels of thermal performance. Insulations are listed in order of increasing performance and, generally, in order of increasing cost. The specific insulation to be used for a particular application is determined through a compromise between cost, ease of application and the effectiveness of the insulation. Consequently, materials, representative test conditions, and engineering approach for the particular application are crucial to achieve the optimum result. The present work is based on energy cost balance for optimizing the thickness of insulated chambers, using foamed or multi layered cryogenic shell. The considered insulation is a uniformly applied outer layer whose thickness varies with the initial and boundary conditions of the studied vessel under steady-state radial heat transfer. An expression of the optimal insulation thickness derived from the total cost function and depending on the geometrical parameters of the container is presented.

Structures of proteases for ubiqutin and ubiquitin-like modifiers

  • Ha, Byung-Hak;Kim, Eunice Eun-Kyeong
    • BMB Reports
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    • v.41 no.6
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    • pp.435-443
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    • 2008
  • Post-translational modifiers can alter the function of proteins in many different ways. The conjugation of ubiquitin (Ub) and ubiqutin-like modifiers (Ubls) to proteins has been shown to be especially crucial in regulating a variety of cellular processes including the cell cycle, growth control, quality control, localization and many more. It is a highly dynamic process and involves a number of enzymes called E1, E2 and E3. Ub and Ubls are removed from the target proteins by deubiquitinating enzymes (DUBs) or Ubl-specific proteases (ULPs), thereby deconjugation can act as an additional level of control over the ubiquitin-conjugation system. In addition, DUBs and ULPs are responsible for activating Ub and Ubls from their inactive corresponding precursor forms. Here we review recent progress in molecular details of these deconjugating enzymes of Ubls.

Cytokines in Depression and Anxiety Disorder (우울증, 불안장애에서의 사이토카인의 역할)

  • Song, Yoon-Jae;Kang, Eun-Ho;Yu, Bum-Hee
    • Anxiety and mood
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    • v.4 no.2
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    • pp.91-98
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    • 2008
  • Depression and anxiety disorders are common psychiatric illnesses whose etiology remains partially understood. The etiology of depression and anxiety disorders is multi-factorial, and abnormalities in neurotransmitter, neuroendocrine system, and brain activation have been implicated in those conditions. However, the pathophysiology of depression and anxiety disorder is certainly not well understood, and some patients with depression or anxiety disorders do not respond to antidepressant therapy. Recently, immunological factors such as cytokines are known to be closely related to central nervous system as well as depression and anxiety disorders. This review highlights recent progress in understanding the function of cytokines in depression and anxiety disorders.

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