• Title/Summary/Keyword: Recovery factor

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High-Power-Factor Boost Rectifier with a Passive Lossless Snubber (무손실 수동스너버를 갖는 고역율 부스트 정류기)

  • 김만고
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.5
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    • pp.617-625
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    • 1998
  • A passive energy recovery snubber for high-power-factor boost rectifier, in which the main switch is implemented with a MOSFET, is described in terms of the equivalent circuits that are operational during turn-on and turn-off sequences. These equivalent circuits are analyzed so that the overshoot voltage across the main switch, the snubber current, and the turn-off transition time can be predicted analytically. From these results, the normalized overshoot voltage is reduced to 1 as $_W2T_on$ varies from zero to $\pi$/2, and then it is fIxed at 1 for $_W2T_on$> $\pi$/2. The peak snubber inductor current is directly proportional to the input current. The turn-offtransition time wltoffvaries from 0 to 2.57, depending on $_W2T_on$. The main switch combined with proposed snubber can be turned on with zero current and turned off at limited voltage stress. The high-power-factor boost rectifier with proposed snubber is implemented, and the experimental results are presented to confirm the validity of proposed snubber.

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The Assessment of Hand for Enzyme Hydrolyzed Denim fabrics(Part I) (셀룰라아제 처리된 데님직물의 태에 관한 연구(제1보);주관적인 태 평가를 위한 척도개발)

  • 김경애;이미식;김정희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.8
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    • pp.1139-1148
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    • 1999
  • This paper discussed the assessment of hand of denim fabrics finished by enzymatic hydrolysis. The semantic differential scale established using the database collected from university students. Analyzing the subjective rating by common factor analysis with oblimin rotation five factors expressing the hand were induced. Factor one was the surface property related to the surface roughness or softness Factor two was the durability which was related to the compactness and bearing strength Factor three was the sense of weight which was related to the thickness and weight. The moisture related properties and the sense of shape recovery were the forth and fifth factors respectively. the evaluations on the surface property weight and moisture related properties were similar by men and women However the shape recovery and the durability were evaluated differently. Surface and weight related properties were important factors judging the hand of fabrics by both group.

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A 13 Week Subcutaneous Toxicity Study of Recombinant Human Epidermal Growth Factor (DWP401) in Mice (Recombinant Human Epidermal Growth Factor (DWP401)의 마우스를 이용한 피하투여 아급성독성시험)

  • 송시환;강부현;신천철;김희연;강진석;심점순;한상섭;노정구
    • Biomolecules & Therapeutics
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    • v.4 no.2
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    • pp.138-147
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    • 1996
  • DWP401, a recombinant human epidermal growth factor, was subcutaneously administered to ICR mice at the dose levels of 0, 0.04, 0.2 and 1.0 mg/kg/day (15rats/sex/group) in order to evaluate the subchronic toxicity. General observations, examinations for food and water consumption, ophthalmoscopy and urinalysis were carried out during the study. For the complete gross and microscopic examinations, 10 mice/ sex/group were sacrificed at the ends of the dosing period, and the remaining animals were sacrificed with a 5 week recovery period. Examinations for hematology and blood biochemistry were also carried out at the time of recovery period. Based on the results, it was thought that the target tissue or organs were mesothelial cell, injection site, spleen, adrenal gland, ovary and transitional epithelial cell of urinary tract, and no observed toxic level of DWP401 was 0.04 mg/kg while definite toxic dose level might be 0.2 mg/kg.

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Effects of Aqueous Extract of Achyranthes Japonica on Functional Recovery in Sciatic Nerve after Crushed Sciatic Nerve Injury in Rats (우슬 추출물이 흰쥐 좌골신경 손상 후 좌골신경의 기능회복에 미치는 영향)

  • Lee, Ma-Seong;Song, Yun-Kyung;Lim, Hyung-Ho
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.2
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    • pp.143-158
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    • 2011
  • Objectives : Peripheral nerve injuries are commonly encountered clinical problem and often result in severe functional deficits. The aim of this study is to evaluate the effects of aqueous extract of Achyranthes japonica(AJ) on functional recovery in sciatic nerve after crushed sciatic nerve injury. Methods : In the present study, the animals in the AJ-treated groups received the aqueous extract of AJ at the respective doses orally for 13 consecutive days. In order to assess the effects of the aqueous extract of AJ on function recovery in crushed sciatic nerve injury, sciatic functional index(SFI) was performed. c-Fos expression in the paraventricular nucleus(PVN) and ventrolateral periaqueductal gray(vIPAG), and neurofilament, and the expressions of brain-derived neurotrophic factor(BDNF), nerve growth factor(NGF) following crushed sciatic nerve injury in rats were investigated. For this, immunohistochemistry and western blot were performed. Results : In the present study, crushed sciatic nerve injury showed characteristic gait changes showing decrease of SFI value and treatment with the aqueous extract of AJ significantly enhanced the SFI value. Neurofilament expression in the sciatic nerve was decreased by crushed sciatic nerve injury and treatment with the AJ increased neurofilament expression. The expressions of BDNF and NGF in the sciatic nerve were increased following crushed sciatic nerve injury and treatment with the AJ significantly controlled the sciatic nerve injury-induced increment of BDNF and NGF expressions. c-Fos expressions in the PVN and vIPAG were increased following crushed sciatic nerve injury and treatment with the AJ significantly suppressed the sciatic nerve injury-induced increment of c-Fos expressions. Conclusions : These results suggest that AJ treatment after crushed sciatic nerve injury is effective in the functional recovery by enhancing axonal regeneration and suppressing of pain.

Reduction of Inflammation and Enhancement of Motility after Pancreatic Islet Derived Stem Cell Transplantation Following Spinal Cord Injury

  • Karaoz, Erdal;Tepekoy, Filiz;Yilmaz, Irem;Subasi, Cansu;Kabatas, Serdar
    • Journal of Korean Neurosurgical Society
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    • v.62 no.2
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    • pp.153-165
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    • 2019
  • Objective : Spinal cord injury (SCI) is a very serious health problem, usually caused by a trauma and accompanied by elevated levels of inflammation indicators. Stem cell-based therapy is promising some valuable strategies for its functional recovery. Nestin-positive progenitor and/or stem cells (SC) isolated from pancreatic islets (PI) show mesenchymal stem cell (MSC) characteristics. For this reason, we aimed to analyze the effects of rat pancreatic islet derived stem cell (rPI-SC) delivery on functional recovery, as well as the levels of inflammation factors following SCI. Methods : rPI-SCs were isolated, cultured and their MSC characteristics were determined through flow cytometry and immunofluorescence analysis. The experimental rat population was divided into three groups : 1) laminectomy & trauma, 2) laminectomy & trauma & phosphate-buffered saline (PBS), and 3) laminectomy+trauma+SCs. Green fluorescent protein (GFP) labelled rPI-SCs were transplanted into the injured rat spinal cord. Their motilities were evaluated with Basso, Beattie and Bresnahan (BBB) Score. After 4-weeks, spinal cord sections were analyzed for GFP labeled SCs and stained for vimentin, $S100{\beta}$, brain derived neurotrophic factor (BDNF), 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase), vascular endothelial growth factor (VEGF) and proinflammatory (interleukin [IL]-6, transforming growth factor $[TGF]-{\beta}$, macrophage inflammatory protein [MIP]-2, myeloperoxidase [MPO]) and anti-inflammatory (IL-1 receptor antagonis) factors. Results : rPI-SCs were revealed to display MSC characteristics and express neural and glial cell markers including BDNF, glial fibrillary acidic protein (GFAP), fibronectin, microtubule associated protein-2a,b (MAP2a,b), ${\beta}3$-tubulin and nestin as well as anti-inflammatory prostaglandin E2 receptor, EP3. The BBB scores showed significant motor recovery in group 3. GFP-labelled cells were localized on the injury site. In addition, decreased proinflammatory factor levels and increased intensity of anti-inflammatory factors were determined. Conclusion : Transplantation of PI-SCs might be an effective strategy to improve functional recovery following spinal cord trauma.

A Study on the Calculation Method of VOCs Emissions Using Equation of State in the Gas Station Tank (상태방정식을 이용한 주유소 탱크에서의 유증기 배출량 산정법에 관한 연구)

  • Park, Taejoon;Oh, Wheesung;Lee, Chang-Eon
    • Journal of the Korean Society of Combustion
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    • v.20 no.4
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    • pp.42-48
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    • 2015
  • This study was investigated the estimation of VOCs (Volatile Organic Compounds) emission from a gas station tank. To improve the atmosphere environmental quality near the gas station, the installation of vapor recovery system has been expanded recently. Therefore, it was necessary to calculate VOCs emissions from the gas station tank with vapor recovery systems for evaluation of their performance. The VOCs emissions are difficult to measure directly because of various sources and irregularly emission by pressure rise. In this study, VOCs emissions were estimated by simple calculation based on the equation of state for measured pressure, temperature and volume of a gasoline tank at a gas station. The result confirmed that the present national emission factor did not have significant discrepancy with the calculated value.

A Study on the Critical Success Factors and Practical Method of Information System Disaster Recovery : Assuring Business Continuity of Information System Interface Specification Modeling (정보시스템 재해복구의 핵심성공요인(CSF)과 실천방안에 관한 연구)

  • Jeong, Young-Hee;Lee, Jung-Hoon;Kim, Eun-Young
    • Journal of Information Technology Services
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    • v.10 no.4
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    • pp.83-101
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    • 2011
  • Since most of companies these days are utilizing the Information system actively, Information System is the most important factor which should be recovered in terms of Business Continuity. However, a lot of enterprises have been outsourcing their Disaster Recovery Center. Therefore, it is highly possible that the information system can not work well and result in the discontinuity of business when any trouble arises because of seperated plan of Business Continuity and Disaster Recovery. The study draws critical success factors for successful disaster recovery through researches of 42 documents. Then, factors are reviewed through interviews with consultants, experts of Business Continuity Plan and the information system officers of domestic banks. Domestic companies can make use of the study when they develop or renew Disaster Recovery Plan or Information System in terms of Business continuity.

The Serum Level of Insulin Growth Factor-1 and Insulin Growth Factor Binding Protein-3 in Children with Henoch-Schönlein Purpura

  • Kim, Hee Jin;Jung, Su Jin;Lee, Jun Ho
    • Childhood Kidney Diseases
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    • v.20 no.1
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    • pp.23-28
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    • 2016
  • Purpose: We investigated whether serum levels of insulin growth factor-1 (IGF-1) and insulin growth factor binding protein-3 (IGFBP-3) are valuable in predicting clinical outcomes or are correlated with other laboratory findings in children with Henoch-$Sch{\ddot{o}}nlein$ purpura (HSP). Methods: We examined 27 children who were consecutively admitted to our hospital with HSP between January 2011 and February 2012. Blood tests (C-reactive protein, white blood cell count, platelet count, erythrocyte sedimentation rate, albumin, immunoglobulin A, complement C3, antineutrophil cytoplasmic antibody, IGF-1, IGFBP-3) and urine tests were performed upon admission. IGF-1 and IGFBP-3 were resampled in the recovery phase. Controls included 473 children whose IGF-1 and IGFBP-3 were sampled for evaluating their growth, at the outpatient department of pediatric endocrinology in our hospital. IGF-1 and IGFBP-3 were compared between the HSP children and controls, and between the acute and recovery phases in HSP children. The ability of these values to predict clinical outcomes including renal involvement was analyzed using bivariate logistic regression analysis (BLRA). Results: IGF-1 and IGFBP-3 were not different between the HSP children and controls ($148.7{\pm}117.6$ vs. $69.2{\pm}96.9$, P=0.290: $3465.9{\pm}1290.9$ vs. $3597.2{\pm}1,127.6$, P=0.560, respectively). There was no significant difference in IGF-1 or IGFBP-3 between acute and recovery phases. Based on the BLRA, no variable, including IGF-1 and IGFBP-3, could predict clinical outcomes including the presence of nephritis Conclusion: We concluded that IGF-1 and IGFBP-3 do not predict clinical outcomes of HSP, including renal involvement, in this study.

Retrospective Study on 469 Halitosis Patients (구취환자 469례에 대한 후향적 연구)

  • Kim, Dae Bok;Kim, Jae Ik;Nam, Seung Kyu;Jeong, Gi Hoon;Kim, Chul Jung;Cho, Chung Sik
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.29 no.5
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    • pp.370-377
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    • 2015
  • There is a growing interest in halitosis and diverse Korean medical studies are being conducted about it. But there are few study about teatment effect of halitosis after Korean medical care, treatment duration, and factor affecting recovery rate. Thus, the purpose of this study is to research clinical characteristic of halitosis patients, factor affecting halitosis, recovery rate of halitosis, treatment duration, factor affecting recovery rate by analyzing halitosis patients retrospectively. People who were over 19 and visited Korean medical clinic in Seoul to want to be treated halitosis in 2014 were analyzed retrospectively. We analyzed general and living characteristics of halitosis patients, halitosis-related symptoms and diseases, level of halitosis and halitosis-related symptoms both before and after treatment, treatment duration of halitosis patients, prescription of halitosis patients, recovery rate of level of halitosis and halitosis-related symptoms by general characteristic and duration of symptoms. Female, thirties, and Nonsmoker had the highest proportion in general characteristic. The average duration of halitosis is 41.6months and treatment duration is 2.55months. The average of sensory evaluation score is 3.40±2.53, subjective evaluation score is 5.02±1.53, lump sensation on throat is 3.52±2.50, postnasal drip is 1.11±1.88, dry mouth is 4.13±2.17, quality of life is 6.07±1.13. Gamichiuitang is used the most among prescriptions. Sensory evaluation, subjective evaluation, lump sensation on throat, postnasal drip, dry mouth, and quality of life had better score compared with pre-treatment. Duration of symptoms is in weak inverse proportion to sensory evaluation, subjective evaluation, dry mouth, quality of life. This study is meaningful in the way to find recovery rate of halitosis after korean medical care, treatment duration, and factor affecting recovery rate not progressed until now. But this study also has limits such as not analyzing objective data using halitosis measuring instrument and lack of methodical scale about quality of life. Therefore, succeeding study such as clinical trials is needed to verify reliability of Korean medical treatment.

Mediating Effects of Hope and Therapeutic Relationship in the Relation between General Social Functions and Mental Health Recovery of Community People with Mental Illness (지역사회 정신장애인의 전반적 사회기능과 정신건강 회복 간의 관계에서 희망과 치료적 관계의 매개효과)

  • Shin, Sun Hwa;Hwang, Jung Hee
    • Research in Community and Public Health Nursing
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    • v.30 no.1
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    • pp.69-78
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    • 2019
  • Purpose: This study tries to test mediating effects of hope and therapeutic relationship in the relation between general social functions and mental health recovery of community people with mental illness. Methods: This study was carried out in a cross-sectional research design. The participants included 217 people with mental illnesses who were enrolled at eight Mental Health Welfare Centers in the Gyeonggi Province. Data were collected from February to May, 2018. The collected data were analyzed using a regression analysis, and SPSS PROCESS macro was used to test the mediating effects. Results: This study analyzed the direct effects of general social functions on the hope, therapeutic relationship and mental health recovery. And general social functions had indirect effects on their mental health recovery via hope and therapeutic relationship. Both hope and therapeutic relationship had dual mediating effects in the influence of general social functions on mental health recovery. Conclusion: The role of hope and therapeutic relationship in the mental health recovery of community people with mental illness is important, and it is confirmed that hope is a powerful factor influencing mental health recovery.