• Title/Summary/Keyword: ccp

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THERMALHYDRAULIC EVALUATIONS FOR A CANFLEX BUNDLE WITH NATURAL OR RECYCLED URANIUM FUEL IN THE UNCREPT AND CREPT CHANNELS OF A CANDU-6 REACTOR

  • Jun, Ji-Su
    • Nuclear Engineering and Technology
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    • v.37 no.5
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    • pp.479-490
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    • 2005
  • The thermalhydraulic performance of a CANDU-6 reactor loaded with various CANFLEX fuel bundles is evaluated by the NUCIRC code, which is incorporated with recent models of pressure drop and critical heat flux (CHF) predictions based on high-pressure steam-water tests for the CANFLEX bundle as well as a 37-element bundle. The distributions of channel flow rate, channel exit quality, critical channel power (CCP), and critical power ratio (CPR) for the CANFLEX bundles (with natural or recycled uranium fuel) in the CANDU-6 reactor fuel channel are calculated by the code. The effects of axial and radial heat flux on CCP are evaluated by assuming that the recycled uranium fuel (CANFLEX-RU) has the same geometric data as the natural uranium fuel bundle (CANFLEX-NU), but a different power distribution due to different fuel composition and refueling scheme. In addition, the effects of pressure tube creep and bearing-pad height are examined by comparing various results of uncrept, and $3.3\%\;and\;5.1\%$ crept channels loaded with CANFLEX bundles with 1.4 mm or 1.7 mm high bearing-pads with those of the 37-element bundle. The distributions of the channel flow rate and CCP for the CANFLEX-NU or -RU bundle show a typical trend for a CANDU-6 reactor channel, and the CPRs are maintained above at least 1.444 (NU) or 1.455 (RU) in the uncrept channel. The enhanced CHF of the CANFLEX bundle (particularly with 1.7mm height bearing-pads) produces a higher thermal margin and considerably less sensitivity to CCP reduction due to the pressure tube creep than the 37-element bundle. The CCP enhancement due to the raised bearing-pads is estimated to be about $3\%\~5\%$ for the CANFLEX-NU and $2\%\~6\%$ for the CANFLEX-RU bundle, respectively.

솔라셀용 uC-Si:H 박막 증착공정을 위한 플라즈마 소스에 대한 고찰 및 multi-hole hollow cathode CCP에 대한 연구

  • Seo, Sang-Hun;Lee, Heon-Su;Lee, Yun-Seong;Jang, Hong-Yeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.409-409
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    • 2010
  • 솔라셀은 차세대 대체 에너지 소스로 최근 큰 각광을 받고 있다. 솔라셀의 제조에 있어 가장 중요한 공정은 마이크로 결정질 및 비결정질 실리콘(uC-Si:H and a-Si:H) 박막을 증착하는 PECVD (Plasma Enhanced CVD)공정이다. 현재까지 이 증착공정을 위한 플라즈마 소스로 CCP(Capacitively Coupled Plasma)가 주로 사용되어 왔다. 그러나, CCP를 플라즈마 소스를 사용한 경우 솔라셀 대량 생산 적용시 다른 방법들에 비해 긴 공정 시간이 해결해야 할 문제점으로 대두되었다. 본 발표에서는 솔라셀의 대량 생산을 위한 마이크로 결정질 실리콘 박막 증착에 있어 현 시점에서 해결되어야 할 문제점에 대해 고찰해 보고자 한다. 현재까지 이러한 문제점들을 해결하기 위해 적용되어 왔던 플라즈마 소스들을 나열하고 이러한 플라즈마 소스에 대한 특성 및 문제점들을 고찰한다. 또한, PECVD 공정상의 문제점을 해결하기 위한 플라즈마 조건을 플라즈마 벌크에서의 전자에너지 분포를 기준으로 제시하고자 한다. 솔라셀용 결정질 실리콘 박막 증착용 플라즈마 소스로 hollow cathode 방전이 가장 유력시되고 있다. 본 연구에서는 CCP 플라즈마에서 hollow cathode 방전시 발생되는 플라즈마 특성에 대한 기초 연구를 제시한다. 기초 연구를 위해 다양한 불활성 가스인 아르콘, 헬륨, 크립톤 가스에 13.56 MHz의 RF 파워를 인가하고 방전되는 플라즈마 밀도 변화를 관찰하였다. 특히, 다양한 hole diameter에서 발생되는 플라즈마 밀도의 변화를 기존 평면 CCP 플라즈마의 밀도에 비교하여 분석함으로써 hole diameter에 따른 효과를 관찰하였다. 이러한 결과는 PIC 시뮬레이션을 통해 얻은 전자에너지 분포함수를 바탕으로 메커니즘을 논의하고자 한다. 마지막으로 솔라셀용 PECVD공정을 위해 고밀도 플라즈마 소스의 필요성뿐 만 아니라 대면적 소스의 구현에 대한 문제점을 고찰하였다. 대면적 공정에서 가장 중요한 핵심 연구 이슈는 공정 균일도를 높이는 것이다. CCP 플라즈마 소스에서 전극의 크기가 대면적화 됨에 따라 발생되는 전자기파 효과에 의한 불균일도에 대해 RF 전자기장 시뮬레이션을 통해 확인하고, 균일도 확보를 위한 방안에 대한 논의하고자 한다.

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Meta-Analysis of Effect in Serum Bio-Markers for Early Diagnosis: Rheumatoid Arthritis

  • Woo, Myoung Soo;Mun, Sora;Kang, Hee-Gyoo
    • Biomedical Science Letters
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    • v.27 no.4
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    • pp.298-309
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    • 2021
  • Rheumatoid arthritis refers to acute and chronic arthritis due to unexplained autoantibody attack. Rheumatoid arthritis should be accompanied by difficulty in mobility and severe distress due to the progression of systemic arthritis. Therefore, this study early diagnoses the effects of Rheumatoid factor (RF), C-reactive protein (CRP), and Anti-cyclic citrullinated peptide (Anti-CCP), which are typical serum markers for rheumatoid arthritis by meta-analysis. Pubmed and EMBASE, were used as PICO criteria, and two independent researchers selected papers according to the criteria set in this study. The selection criteria was a study of patients with rheumatoid arthritis who developed early onset, and the paper was evaluated using the NCS. Forest plot and Funnel plot graphs for each serum marker were calculated using Revman 5.4. After finding 193 papers on Pubmed and 184 papers on EMBASE and selecting according to the criteria, a total of 41 papers were used for the analysis. The magnitude of the effect that appears in the Forest plot of RF with the Mean differnce value is 134.34, CRP is 21.42 and Anti-CCP is 270.41. The magnitude of the effect of Anti-CCP in meta-analysis was analyzed to be larger than that of RF and CRP, and it is considered that the development of early-diagnosis serum markers using Anti-CCP and additional retrospective studies are highly effective. The combination of RF, CRP, and Anti-CCP as a panel marker is expected to be very efficient.

Immunoenhancing Effects of Euglena gracilis on a Cyclophosphamide-Induced Immunosuppressive Mouse Model

  • Yang, Hyeonji;Choi, Kwanyong;Kim, Kyeong Jin;Park, Soo-yeon;Jeon, Jin-Young;Kim, Byung-Gon;Kim, Ji Yeon
    • Journal of Microbiology and Biotechnology
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    • v.32 no.2
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    • pp.228-237
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    • 2022
  • In this study, the effects of the immune stimulator Euglena gracilis (Euglena) in cyclophosphamide (CCP)-induced immunocompromised mice were assessed. The key component β-1,3-glucan (paramylon) constitutes 50% of E. gracilis. Mice were orally administered Euglena powder (250 and 500 mg/kg body weight (B.W.)) or β-glucan powder (250 mg/kg B.W.) for 19 days. In a preliminary immunology experiment, ICR mice were intraperitoneally injected with 80 mg of CCP/kg B.W. during the final 3 consecutive days. In the main experiment, BALB/c mice were treated with CCP for the final 5 days. To evaluate the enhancing effects of Euglena on the immune system, mouse B.W., the spleen index, natural killer (NK) cell activity and mRNA expression in splenocytes lungs and livers were determined. To detect cytokine and receptor expression, splenocytes were treated with 5 ㎍/ml concanavalin A or 1 ㎍/ml lipopolysaccharide. The B.W. and spleen index were significantly increased and NK cell activity was slightly enhanced in all the experimental groups compared to the CCP-only group. In splenocytes, the gene expression levels of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10, IL-6, and IL-12 receptor were increased in the E. gracilis and β-glucan groups compared to the CCP-only group, but there was no significant difference. Treatment with 500 mg of Euglena/kg B.W. significantly upregulated dectin-1 mRNA expression in the lung and liver compared to the CCP-only group. These results suggest that Euglena may enhance the immune system by strengthening innate immunity through immunosuppression.

Anti-inflammatory Effect of Cornus Officinalis fruit extract and Cornus Officinalis Fruit Cheonghyeol Plus in Human Umbilical Vein Endothelial Cell (인간 제대정맥 내피세포에서 산수유와 산수유청혈플러스의 항염증효과)

  • Jeong-hui Kim;Ho-ryong Yoo;In-chan Seol;Yoon-sik Kim
    • The Journal of Korean Medicine
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    • v.43 no.3
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    • pp.106-121
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    • 2022
  • Objectives: The purpose of this study was to investigate the anti-inflammatory effect of Cornus Officinalis fruit extract(CE) and Cornus Officinalis Fruit Cheonghyeol Plus(CCP) in Human Umbilical Vein Endothelial Cell. Methods: We measured cell viability of CE, CCP and treated HUVEC with TNF-α. We measured the mRNA expression levels of KLF2, eNOS, MCP-1, ICAM-1, VCAM-1, the protein expression levels of KLF2, eNOS, MCP-1, ICAM-1, VCAM-1, and the protein phosphorylation level of ERK, JNK, p38 and the biomarker expression levels of MCP-1, ICAM-1, VCAM-1. Results: 1.CE incresed the mRNA, protein expression levels of KLF2, eNOS at concentrations of 100㎍/㎖ compared to the control group. CE decresed the mRNA, protein and biomarker expression levels of MCP-1,ICAM-1,VCAM-1 at concentrations of 100㎍/㎖ compared to the control group. CE decresed the protein phosphorylation level of p38 at concentrations of 100㎍/㎖ compared to the control group. 2. CCP incresed the mRNA, protein expression levels of KLF2, eNOS at concentrations of 100㎍/㎖ or more compared to the control group. CCP decresed the mRNA, protein and biomarker expression levels of MCP-1, ICAM-1, VCAM-1 at concentrations of 100㎍/㎖ or more compared to the control group. CCP decresed the protein phosphorylation level of ERK at concentrations of 100㎍/㎖ or more, p38 at concentrations of 200㎍/㎖ or more, and JNK at concentrations of 400㎍/㎖ compared to the control group. Conclusions: These results present that CE and CCP has anti-inflammatory effect in HUVEC. So, it could help treat or prevent inflammation in vein caused by dyslipidemia and contribute prevention of cardiovascular and cerebrovascular cerebrovascular diseases.

A Geometric Characterization of Complete Continuity Property

  • Lim, Jong Sul;Eun, Gwang Sik;Yoon, Ju Han
    • Journal of the Chungcheong Mathematical Society
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    • v.7 no.1
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    • pp.217-226
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    • 1994
  • We introduce the notion of the mean Bocce dentable and provide the geometric characterization of the CCP. We show that X has the CCP if and only if every bounded subset of X is mean Bocce dentable.

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Physical and Electrical Characteristics of SrBi$_2$Ta$_2$O$_9$ thin Films Etched with Inductively Coupled Plasma Reactive Ion Etching System (유도결합형 플라즈마 반응성 이온식각 장치를 이용한 SrBi$_2$Ta$_2$O$_9$ 박막의 물리적, 전기적 특성)

  • 권영석;심선일;김익수;김성일;김용태;김병호;최인훈
    • Journal of the Microelectronics and Packaging Society
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    • v.9 no.4
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    • pp.11-16
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    • 2002
  • In this study, the dry etching characteristics of $SrBi_2Ta_2O_9$ (SBT) thin films were investigated by using ICP-RIE (inductively coupled plasma-reactive ion etching). The etching damage and degradation were analyzed with XPS (X-ray photoelectron spectroscopy) and C-V (Capacitance-Voltage) measurement. The etching rate increased with increasing the ICP power and the capacitively coupled plasma (CCP) power. The etch rate of 900$\AA$/min was obtained with 700 W of ICP power and 200 W of CCP power. The main problem of dry etching is the degradation of the ferroelectric material. The damage-free etching characteristics were obtained with the $Ar/C1_2/CHF_3$ gas mixture of 20/14/2 when the ICP power and CCP power were biased at 700 W and 200 W, respectively. The experimental results show that the dry etching process with ICP-RIE is applicable to the fabrication of the single transistor type ferroelectric memory device.

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Biological and Chemical Hazards Factor Analysis for CCP(Critical Control Point) in Fried Process of Fried Noodles (유탕면류의 유탕공정 중 중요관리점(CCP)을 위한 미생물학적, 화학적 위해요소분석)

  • Kwon, Sang-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.8
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    • pp.3578-3585
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    • 2012
  • The purpose of this study was to establish the critical limit at CCP (Critical Control Point) of HACCP (Hazard Analysis Critical Control Point) system for instant noodle and it was conducted at P company in Ichen(Gyeonggi-do), Korea. According to the CCP, Fried process were experimented to removal and decrease of microbiological and chemical hazards by measuring of each temperature and times. As a result, the standard plate count and pathogenic microorganism were not detected by fried processing (Temperature : $145{\pm}10^{\circ}C$, Time : $75{\pm}30$ sec). The acid value of chemical hazards produced by fried processing was able to manage, showed lower (0.2) than the legal limit (0.6). Air-borne bacterial examination results detected(3 CFU/mL, 3 CFU/mL) in the Frying Room and Steam Room. Therefore, the CCP-BC of fried process would be a great alternative to prevent and remove hazard analysis, such as general and pathogenic microorganism (E. coli O157:H7, B. cereus, Listeria monocytogenes, Salmonella spp, Sthaph. aureus etc), chemical hazard analysis. In conclusion, it suggested that HACCP plan was necessary for management standard and systematic approach in establishement of critical limit, solving the problem, method of verification, education and records management by fried processing.

Variability in Two Species of Osmeridae (Hypomesus nipponensis and Mallotus villosus) (바다빙어과 2종 (Hypomesus nipponensis와 Mallotus villosus)의 변이)

  • Yoon, Jong-Man
    • Development and Reproduction
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    • v.12 no.2
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    • pp.151-158
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    • 2008
  • The variability within and between Korean pond-smelt (Hypomesus nipponensis; KPS) and Canadian capelin (Mallotus villosus; CCP) were studied in order to clarify the genetic distances and differences. The dendrogram obtained by the seven primers indicates cluster 1 (KOREAN 01$\sim$KOREAN 11) and cluster 2 (CANADIAN 12$\sim$CANADIAN 22). The longest genetic distance displaying significant molecular differences was found to exist between individuals in the two geographic species of Osmeridae, between individuals' no. 10 of Korean and no. 18 of Canadian (0.686). 121 unique shared loci to each species, with an average of 17.3 per primer, were observed in the KPS species, and 264 loci, with an average of 37.7 per primer, were observed in the CCP species. 77 shared loci by the two species, with an average of 11.0 per primer, were observed in the two fish species. RAPD analysis showed that the KPS species was more genetically diverse than the CCP species. KPS species may have high levels of genomic DNA variability owing to the introduction of the wild individuals from the other sites to sampling sites although it may be the geographically diverse distribution of this species. As stated above, the existence of species discrimination and genetic variability between the KPS and the CCP species was identified by RAPD analysis.

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The Development of Check equipment Maintaining air pressure constantly for Automobile (자동차용 공기압을 일정하게 유지하는 검사 장치의 개발)

  • Kim, Seok-Hyun
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2009.05a
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    • pp.184-189
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    • 2009
  • The Measurement system of auto parts are currently precious ones in the case of most of them. In this paper We tried to implement low_cost equipment. There are many auto parts. Among them CCP(Canister Controlled Purge Solenoid) which have difficulties in the control of air fluid currently have been main object. According to the use of air amount. Required time to maintain vacuum air pressure constantly need three or four minutes but the aim of this development try to achieve keeping vacuum pressure within less shorter time, Under the constant air pressure, We try to develop control check system of auto parts CCP(Canister Controlled Purge Solenoid).

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