• 제목/요약/키워드: model factor

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Analysis of GIUH Model by Using GIS in River Basin (하천유역에서 GIS를 이용한 GIUH 모형의 해석)

  • Heo, Chang-Hwan;Lee, Sun-Tak
    • Journal of Korea Water Resources Association
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    • v.35 no.3
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    • pp.321-330
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    • 2002
  • This study aims at the analysis of the geomorphological instantaneous unit hydrograph model (GIS-GIUH) with geographic information system for the rainfall-runoff analysis of watershed which is ungaged or doesn't have sufficient hydrologic data. The rainfall-runoff analysis was performed in Wi stream(Dongkok, Koro, Miseung, Byeungchun, Hyoreung, Museung) which is a representative experimental river basin of IHP. In the process of analysis of the GIUH model, developed GIS-GIUH model and Rosso-GIUH model were applied the study basin and computed hydrographs by these models were compared with observed hydrograph. The GiS-GIUH model shows more closely to the observed hydrograph than Rosso-GIUH model in the peak discharge of the hydrograph. For the development of the GIS-GIUH model, Gamma function factor N was given by N=3.25( $R_{B}$/ $R_{A}$)$^{0.126}$ $R_{L}$$^{-0.055}$, which is the relation of the watershed geomorphological factor, K was also obtained as K=1.50( $R_{A}$/( $R_{B}$. $R_{L}$))/$^{0.10}$.(( $L_{{\Omega}}$+ $L_{{\Omega}-1}$)/V)$^{0.37}$. As the results of analysis, it was found that GIS-GIUH model can be applied to an ungaged watersheds.eds.

Structural performance evaluation of a steel-plate girder bridge using ambient acceleration measurements

  • Yi, Jin-Hak;Cho, Soojin;Koo, Ki-Young;Yun, Chung-Bang;Kim, Jeong-Tae;Lee, Chang-Geun;Lee, Won-Tae
    • Smart Structures and Systems
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    • v.3 no.3
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    • pp.281-298
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    • 2007
  • The load carrying capacity of a bridge needs to be properly assessed to operate the bridge safely and maintain it efficiently. For the evaluation of load carrying capacity considering the current state of a bridge, static and quasi-static loading tests with weight-controlled heavy trucks have been conventionally utilized. In these tests, the deflection (or strain) of the structural members loaded by the controlled vehicles are measured and analyzed. Using the measured data, deflection (or strain) correction factor and impact correction factor are calculated. These correction factors are used in the enhancement of the load carrying capacity of a bridge, reflecting the real state of a bridge. However, full or partial control of the traffic during the tests and difficulties during the installment of displacement transducers or strain gauges may cause not only inconvenience to the traffic but also the increase of the logistics cost and time. To overcome these difficulties, an alternative method is proposed using an excited response part of full measured ambient acceleration data by ordinary traffic on a bridge without traffic control. Based on the modal properties extracted from the ambient vibration data, the initial finite element (FE) model of a bridge can be updated to represent the current real state of a bridge. Using the updated FE model, the deflection of a bridge akin to the real value can be easily obtained without measuring the real deflection. Impact factors are obtained from pseudo-deflection, which is obtained by double-integration of the acceleration data with removal of the linear components on the acceleration data. For validation, a series of tests were carried out on a steel plategirder bridge of an expressway in Korea in four different seasons, and the evaluated load carrying capacities of the bridge by the proposed method are compared with the result obtained by the conventional load test method.

Evaluation of factors affecting sensory neural hearing loss (감각신경성 청력손실에 영향을 미치는 제 요인에 관한 연구)

  • Hong, Seong-Chul;Bae, Seong-Wook;Lee, Jong-Young
    • Journal of Preventive Medicine and Public Health
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    • v.31 no.2 s.61
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    • pp.249-264
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    • 1998
  • Reports on a potential relationship between sensory neural hearing loss(SNHL) and cardiovascular or hematologic factor show that the results are controversial. A detailed analysis of risk factors in the development of SNHL was carried out in 3,050 non-noise exposed healthy worker. The mean hearing threshold of both ears at 500, 1000, 2000, 4000, 8000Hz was measured and the effect of age, possible cardiovascular risk factor and hematologic factor (blood viscosity and hemostatic factors) on SNHL were evaluated. first, each of these were associated with loss of hearing sensitivity when univariately and multivariatively analysed. In a multiple regression model, age, sex, body mass index, WBC and total cholesterol level were independently associated with the mean of hearing sensitivity decrease at 4000 and 8000Hz. Second, study subjects were divided into two group (normal vs SNHL) and we compare the possible risk between both groups, and analysed univariate and multivariative logistic model. In a multiple logistic regression model, age, sex, body mass index, WBC and total cholesterol level, total protein, platelet were independently associated with SNHL. Our results show that we have some reliable indices of susceptibility to SNHL using cardiovascular measures or biochemical factor, but future, more extensive studies are required.

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An Assessment Model on Sustainability of Local City (지방도시의 지속가능성 평가모형)

  • Hong, Young-Rok;Kwon, Sang-Zoon;Myung, Hyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.4
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    • pp.1-12
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    • 1999
  • This study aims to find basic data for using the quantitative assessment of the sustainability and establishing the systematic index of the planning for local cities to consider the environmentally sound and sustainable development. The research designs to review professional responding to surveys preceded by separate questionnaires and interviews from book reviews, and suggests to make an assessment model of the sustainability for local cities. The research found consequently as follows. Firstly, the research survey items were decides totally 52, grouped 9 assessmental issues and distributed under 4 assessmental domains for the sustainability from the references of book reviews. Secondly, the research result concentrated on the followings from the professional responding to surveys. 1. A most influent factor is the distribution of animals and plants in a nature domain. The next influent factors are the ratio of mass-transportation systems, the numbers of the species of animals and plants, the acreage of conservative forestry, the numbers of reused water resources, and the usage number of water supply, orderly in the nature domain. 2. A most influent factor is the usage number of synthetic detergents in a pollution domain. The next influent factors are the volume of waste water, the number of registered vehicles, the degree of soil pollution, and the charge of development imposition, orderly in the pollution domain. 3. A most influent factor is the acreage of athletic facilities, in an urban domain. the next influent factors are the acreage of recreational facilities, the number and acreage of cultural assets, the number of cultural facilities, the acreage of landscape conservation area, the charge of cultural asset management, orderly in the urban domain. 4. A most influent factor is the number of waste disposal facilities in a participation domain. The next influent factors are the capacity of reused waste, the usage of synthetic detergents, the ratio of waste water disposal, orderly in the participation domain. 5. A most contributed influent domain to the assessment of the sustainability for local cities is the urban domain. The next influent domains are nature domain, participation domain, and pollution domain, orderly in the contribution of the assessment of the sustainability. But, the pollution domain is little relationship with the sustainability. Therefore, it is clear that the abundant greens and the improved level of culture are dominant influences on the sustainabiligy, as like improving the ratio of roadside trees, the acreage of parks, and enlarging the number of cultural facilities.

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Wound Healing Effects of Rose Placenta in a Mouse Model of Full-Thickness Wounds

  • Kim, Yang Woo;Baek, Seung Ryeol;Lee, Eun Sook;Lee, Sang Ho;Moh, Sang Hyun;Kim, Soo Yun;Moh, Ji Hong;Kondo, Chieko;Cheon, Young Woo
    • Archives of Plastic Surgery
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    • v.42 no.6
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    • pp.686-694
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    • 2015
  • Background Rosa damascena, a type of herb, has been used for wound healing in Eastern folk medicine. The goal of this study was to evaluate the effectiveness of rose placenta from R. damascena in a full-thickness wound model in mice. Methods Sixty six-week-old C57BL/6N mice were used. Full-thickness wounds were made with an 8-mm diameter punch. Two wounds were made on each side of the back, and wounds were assigned randomly to the control and experimental groups. Rose placenta ($250{\mu}g$) was injected in the experimental group, and normal saline was injected in the control group. Wound sizes were measured with digital photography, and specimens were harvested. Immunohistochemical staining was performed to assess the expression of epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), transforming growth factor-${\beta}1$ (TGF-${\beta}1$), and CD31. Vessel density was measured. Quantitative analysis using an enzyme-linked immunosorbent assay (ELISA) for EGF was performed. All evaluations were performed on postoperative days 0, 2, 4, 7, and 10. Statistical analyses were performed using the paired t-test. Results On days 4, 7, and 10, the wounds treated with rose placenta were significantly smaller. On day 2, VEGF and EGF expression increased in the experimental group. On days 7 and 10, TGF-${\beta}1$ expression decreased in the experimental group. On day 10, vessel density increased in the experimental group. The increase in EGF on day 2 was confirmed with ELISA. Conclusions Rose placenta was found to be associated with improved wound healing in a mouse full-thickness wound model via increased EGF release. Rose placenta may potentially be a novel drug candidate for enhancing wound healing.

Transplantation of Brain-Derived Neurotrophic Factor-Expressing Mesenchymal Stem Cells Improves Lower Urinary Tract Symptoms in a Rat Model (뇌유래신경영양인자 발현 중간엽 줄기세포의 하부요로증상 개선 효과)

  • Jeon, Seung Hwan;Park, Mi-Young
    • Korean Journal of Clinical Laboratory Science
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    • v.52 no.4
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    • pp.417-424
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    • 2020
  • This study aimed to explore the effects of brain-derived neurotrophic factor (BDNF), produced by engineered immortalized mesenchymal stem cells (imMSC), on lower urinary tract symptoms (LUTS) in a rat model with neurogenic bladder (NB). Forty-eight Sprague-Dawley (SD) rats were randomly divided into the following groups: Sham control, LUTS, LUTS+imMSC (treated with immortalized MSC), and LUTS+BDNF-eMSC (treated with BDNF-expressing MSC) groups. LUTS was induced by a crush injury to the major pelvic ganglion (MPG). Bladder function was tested under anesthesia, and bladder tissue strips were collected thereafter for contractility test and western blot analysis. Western blot results showed that the expression of both Angiopoietin 1 (Ang 1) and platelet-derived growth factor (PDGF) increased with MSC injection. The effect of treatment with BDNF-eMSC on LUTS was also evaluated, and the results were found to be better than those with imMSC (P<0.05). BDNF-eMSC prevented fibrosis in the bladder tissue and significantly reduced caspase-3 levels. In conclusion, high expression of BDNF in vivo resulted in recovery of bladder function and contractility, along with the inhibition of apoptosis in a rat model.

Development and Validation Study of the Korean Version of Working Relationship Scale (한국형 실천관계 척도 정신장애인 용 개발 연구)

  • Kwon, Jayoung
    • Korean Journal of Social Welfare
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    • v.65 no.3
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    • pp.239-263
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    • 2013
  • This research was carried out in order to develop and validate the Korean Version of Working Relationship Scale for Mentally Disabled Persons, which measures the working relationship between a mentally disabled person and his or her case manager. The first step taken to develop this scale was to construct sample items for the Working Relationship Scale using literature research and three focus group interviews of mentally disabled persons who use local mental health services. Secondly, mentally disabled people were surveyed with these sample items and two professors from the department of social work who specialize in mental health social work and two licensed mental health social workers working in the community mental health field reviewed these sample items to select and compile a final version of the scale. Lastly, the scale's reliability and validity was verified through an empirical study of 569 mentally disabled persons who surveyed the final selection of items. An explanatory factor analysis showed that the sample items can be grouped into three factors. Factor 1 is 'Professional Contribution Factor,' which is related to the professional practice of the case manager; Factor 2 is 'Negative Working Relationship Factor'; and Factor 3 is 'Emotional Bond Factor,' which measures the intimacy between the case manager and the mentally disabled person. A confirmatory analysis of the three-factor format that was discovered in the explanatory factor analysis was carried out with the rest of the randomly divided data, which showed that the model demonstrated a goodness-of-fit. The convergence validity between similar concepts appeared to be appropriate as well. Based on these results, the Korean Version of Working Relationship Scale for Mentally Disabled Persons consisting of a final 33 items is developed and proposed and its implications in social work are discussed.

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Mechanism of Environmentally-Induced Stress Corrosion Cracking of Zr-Alloys

  • Park, Sang Yoon;Kim, Jun Hwan;Choi, Byung Kwon;Jeong, Yong Hwan
    • Corrosion Science and Technology
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    • v.6 no.4
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    • pp.170-176
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    • 2007
  • Iodine-induced stress corrosion cracking (ISCC) properties and the associated ISCC process of Zircaloy-4 and an Nb-containing advanced nuclear fuel cladding were evaluated. An internal pressurization test with a pre-cracked specimen was performed with a stress-relieved (SR) or recrystallized (RX) microstructure at $350^{\circ}C$, in an iodine environment. The results showed that the $K_{ISCC}$ of the SR and RX Zircaloy-4 claddings were 3.3 and 4.8MPa\;m^{0.5}, respectively. And the crack propagation rate of the RX Zircaloy-4 was 10 times lower than that of the SR one. The chemical effect of iodine on the crack propagation rate was very high, which was increased $10^4$ times by iodine addition. Main factor affecting on the micro-crack nucleation was a pitting formation and its agglomeration along the grain boundary. However, this pitting formation on the grain-boundary was suppressed in the case of an Nb addition, which resulted in an increase of the ISCC resistance when compared to Zircaloy-4. Crack initiation and propagation mechanisms of fuel claddings were proposed by a grain boundary pitting model and a pitting assisted slip cleavage model and they showed reasonable results.

A Study on the Effect of the Biodegradability of the Composting Bulking Agent in the Swine Manure-Composting (충진재의 생분해도가 돈분 퇴비화 효율에 미치는 영향에 관한 연구)

  • 김성균;최경호;정문식
    • Journal of Environmental Health Sciences
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    • v.23 no.2
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    • pp.35-43
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    • 1997
  • A study on the effect of the biodegradability of the composting bulking agent in the swine manurecomposting was carried out in a batch system. The purpose of this study is to prove the effect of the biodegradability of the composting-bulking agent on the efficiency of the composting. In this study, it is the lignins: Klason-Lignin in the volatile solid that the index of the biodegradability of the composting-material mixes which are pig manure-rice straw pig manure-sawdusts pig manuremixture of rice and ricestraw (2:1) pig manure-mixture of rice and sawdust (1:1). It was carried out in the same condition (moisture contents, air supply rate, C/N ratio, initial input weight, porosity-structure) except the biodegradability of the raw material mixes. One of the results from this study is that the biodegradability of the bulking agent in the sense of the VS lignin content is not an insignificant factor in composting reaction. The less contents of the lignin in VS, the more efficiencies of the cornposting reaction in use of these parameters for the degree of the reaction: temperature, the trends of the ash contents, the change pattern of the C/N ratio. Under some assumptions, it is able to induce rough model on the relation of the VS lignin contents with the efficiency of the degradability. In this model, the biodegradability of the bulking agent is not an insignificant factor however, it is flexible within some degrees of range.

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Characteristics of Resilient Modulus of Reinforced-Roadbed Materials Using Large Repetitive Triaxial Test (대형반복삼축시험에 의한 강화노반 재료의 회복탄성계수 특성 분석)

  • Lim, Yu-Jin;Lee, Jin-Ug;Hwang, Jung-Kyu;Park, Mi-Yun
    • Proceedings of the KSR Conference
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    • 2011.10a
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    • pp.1115-1122
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    • 2011
  • Reinforced-Roadbed materials are usually composed of crushed stones. Repeated load application can induce deformation in the reinforced-roadbed layer so that it causes irregularity of track. Thus it is important to develop a prediction model of elastic modulus based on stress-strain relation under repeatitive load in order to investigate behavior of reinforced roadbed. The prediction model of elastic modulus of the material can be obtained from repeated triaxial test. However, a proper size of the sample for the test must be used. In this study, a large repeatitive triaxial test apparatus with the sample size of diameter of 30 cm and height of 60cm was adapted for performing test of the crushed stone reinforced-roadbed considering large particle size to get resilient modulus Mr. The obtained resilient modulus was compared to shear modulus obtained from mid size resonant column test. The sample size effect is somewhat large enough so that it is required to design a scale factor based on similarity law in order to use smaller samples for getting elastic modulus of the crushed stone reinforced-roadbed material. A scale factor could be obtained from this study.

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