• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.1 s.41
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• pp.1-7
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• 2005

The optimal seismic retrofitting of NPP(Nuclear Power Plant) cabinet structures that contain seismic category 1 relays was studied in this paper. During earthquake event, the failure modes of relays are not appeared in form of structural failure, but are appeared in form of contact chatter of relay. Therefore, the retrofitting of cabinet has to be aimed at the reducing of the structural response, such as acceleration. In this study, the optimal characteristic values of dampers were searched by ${\mu}$-GA (micro-Genetic Algorithm) scheme for several installation patterns. To keep accuracy and efficiency of analysis, the structural models of cabinet were considered as a frame structure. The responses of structure were obtained inform of acceleration response spectra derived from the results of nonlinear time history analysis including damping nonlinearity. The objective function of the optimum procedure was constructed based on the maximum ratio of maximum spectral value and target GERS (General Equipment Ruggedness Spectra). The results show the good improvements of fitness for adequate retrofitting pattern. Especially, the improvements of fitness were remarkable when the values of damping exponents are low.

• Journal of Korea Port Economic Association
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• v.38 no.4
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• pp.199-214
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• 2022

A relative important analysis was conducted to determine what factors are required for port selection in Mokpo New Port and what needs to be addressed first in order to expand automobile and steel cargo handling. The port selection factors of Mokpo New Port were classified into 4 major and 13 intermediate categories, and AHP analysis was used. As a result, items such as 'port facilities', 'accessibility to international ports', 'port facility usage fees', and 'connectivity with neighboring cities/ports' were evaluated as important. The respondent groups were divided into shipowner and shipper, port operator and stevedore, and public official, and an analysis of variance (ANOVA) was conducted to verify if there was a difference in perception between the groups. As a result, shipowner and shipper, port operator and stevedore were similar, but there was a difference from public official group. Shipowner and shipper, port operator and stevedore with similar response characteristics were classified into the 'port practitioner' group, and public official were classified into the 'port policy maker' group, and the difference in perception between the group was tested. Therefore, there were differences in some major category items, and even in the intermediate category items such as 'possession of adjacent hinterland industrial complex', 'cargo equipment', '24-hour port operation', 'inland transportation cost', 'accessibility to international ports', 'marketing and incentives' with statistical. In other words, the 'port practitioner' group evaluated items that can increase cargo creation and handling productivity as important whereas the 'port policy maker' group considers port development and policies such as port infrastructure, connectivity with other ports, and incentive support items are more important.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.396-401
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• 1995

Epoxy coated reinforcing steels (ECRs) were acquired from ten sources and coatings from each source were initially characterized in terms of defects, thickness, solvent extraction weight loss and hardness. Testing involved exposure in three aqueous solutions at elevated temperature (8$0^{\circ}C$) and in chloride-contaminated concrete slabs under outdoor exposure, It was found that the density and size of coating defects was the promary factor affecting ECR performance. The equivalent circuit analysis using electrochemical impedance spectroscopy (EIS) data indicated that the impedance response for well-performing ECR specimens showed no signs of active degradation at the interface although diffusional processes similar to those noted for poorly performing bars occurred here. Experimental results also indicated a relationship between corrosion behavior and bar source. Weight loss upon solvent extraction correlated with impedance reduction from hot water exposure. Coating defects during most of the tests, especially in high pH solutions containing chloride ions. ECRs with excessive coating defects, either initially present or ones which developed in service, performed poorly in every test category regardless of source. Forms of coating failure were extensive rusting at defects, blistering, wet adhesion loss, cathodic delamination, underfilm corrosion and coating cracks. These occurred sequentially or concurrently, depending on the condition of the ECR and nature of the environment

• KIEAE Journal
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• v.15 no.5
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• pp.5-12
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• 2015

Purpose: Retention and infiltration of small and frequently-occurring rainfall by LID facilities account for a large proportion of the annual precipitation volume. Based on 4 standard facilities such as Porous Pavement, Infiltration Trench, Cylindrical Infiltration Well, Rectangular Infiltration Well by Seoul Metropolitan Handbook of the Prior Consultation for LID. The total retention volume of each facility was calculated according to the type and size. The Purpose of this study is to find out the quantitative relationship between Percentile Rainfall Event and Design Volume of Infiltration Facilities. Methode: For the estimation of Percentile Rainfall Event, Daily Precipitation of Seoul from 2005 to 2014 was sorted ascending and the distribution of percentile was estimated by PERCENTILE spreadsheet function. The managed Rainfall Depth and Percentile of each facility was calculated at the several sizes. In response to the rainwater charge volume of 5.5mm/hr by the Category "Private large site", the 3 types of facilities were planned for example. The calculated Rainfall Depth and Percentile were 54.4mm and 90% by the use of developed Calculation-Module based on the Spreadsheet program. Result: With this Module the existing Designed Infiltration volume which was introduced from Japan was simply converted to the Percentile-Rainfall-Event used in USA.

• Physical Therapy Korea
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• v.20 no.3
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• pp.89-99
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• 2013

The purposes of this study were: 1) to show the item difficulty hierarchy of walking/moving construct of the International Classification of Functioning, Disability and Health-Activity Measure (ICF-AM), 2) to evaluate the item-level psychometrics for model fit, 3) to describe the relevant physical activity defined by level of activity intensity expressed as Metabolic Equivalent of Tasks (MET), and 4) to explore what extent the empirical activity hierarchy of the ICF-AM is linked to the conceptual model based on the level of energy expenditure described as MET. One hundred and eight participants with lower extremity impairments were examined for the present study. A newly created activity measure, the ICF-AM using an item response theory (IRT) model and computer adaptive testing (CAT) method, has a construct on walking/moving construct. Based on the ICF category of walking and moving, the instrument comprised items corresponding to: walking short distances, walking long distances, walking on different surfaces, walking around objects, climbing, and running. The item difficulty hierarchy was created using Winstep software for 20 items. The Rasch analyses (1-parameter IRT model) were performed on participants with lower extremity injuries who completed the paper and pencil version of walking/moving construct of the ICF-AM. The classification of physical activity can also be performed by the use of METs that is often preferred to determine the level of physical activity. The empirical item hierarchy of walking, climbing, running activities of the ICF-AM instrument was similar to the conceptual activity hierarchy based on the METs. The empirically derived item difficulty hierarchy of the ICF-AM may be useful in developing MET-based activity measure questionnaires. In addition to convenience of applying items to questionnaires, implications of the finding could lead to the use of CAT method without sacrificing the objectivity of physiologic measures.

• Molecular & Cellular Toxicology
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• v.2 no.3
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• pp.193-201
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• 2006

Cephalexin, one of most widely prescribed cephalosporin, has been reported to cause acute renal failure as a side effect in human and experimental animals. Although numerous animal studies have been reported for the cephalosporin nephrotoxicity, the molecular and cellular nephrotoxic mechanisms of cephalexin are still unknown. This investigation evaluated the time-dependent gene expression profile of kidney in mouse during cephalexin induced nephrotoxicity. C57BL/6 female mice were administered either saline or 1,000 mg/kg cephalexin intraperitoneally. Mice were sacrificed at 3, 6, and 24 hr after administration. Blood biochemical and histopathological results indicated cephalexin induced nephrotoxicity. Microarray experiment carried out using Affymetrix $GeneChip^{(R)}$. There were 198 informative genes that were significantly expressed >5-fold versus control at 3, 6, and 24 hr (p<0.01), of which 156 and 42 were up-and down-regulated, respectively. Major classes of up-regulated genes at 3, 6 hr included those involved in MAPK/Jak-STAT signaling pathway and immune response such as cytokine-cytokine receptor interaction and complement and coagulation cascades. At 24 hr, up-regulated genes were mainly involved in regeneration/repair and immune response; down-regulated genes were generally associated with transporters and intermediary metabolism. Among the up-regulated genes at 24 hr, several potential biomarkers on nephrotoxicity such as Kim-1, Fga, Timp1, and Slc34a2 were clustered in a same category. In addition, Tnfrsf12a and Lcn2 which were consistently up-regulated (>5 fold) were also included as potential biomarkers. These results may provide clues for elucidating the mechanism of cephalexin induced nephrotoxicity and evaluating potential biomarkers to assess nephrotoxicity.

• Molecular & Cellular Toxicology
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• v.3 no.2
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• pp.137-144
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• 2007

The mechanism of cytotoxicity of doxifluridine, a prodrug fluorouracil (5-FU), has been ascribed to the misincorporation of fluoropyrimidine into RNA and DNA and to the inhibition of the nucleotide synthetic enzyme thymidylate synthase. Increased understanding of the mechanism of 5-FU has led to the development of strategies that increases its anticancer activity or predicts its sensitivity to patients. Using GeneChip?? Rhesus Macaque Genome arrays, we analyzed gene expression profiles of doxifluridine after two weeks repeated administration in cynomolgus monkey. Kegg pathway analysis suggested that cytoskeletal rearrangement and cell adhesion remodeling were commonly occurred in colon, jejunum, and liver. However, expression of genes encoding extracellular matrix was distinguished colon from others. In colon, COL6A2, COL18A1, ELN, and LAMA5 were over-expressed. In contrast, genes included in same category were down-regulated in jejunum and liver. Interestingly, MMP7 and TIMP1, the key enzymes responsible for ECM regulation, were overexpressed in colon. Several studies were reported that both gene reduced cell sensitivity to chemotherapy-induced apoptosis. Therefore, we suggest they have potential as target for modulation of 5-FU action. In addition, the expression of genes which have been previously known to involve in 5-FU pathway, were examined in three organs. Particularly, there were more remarkable changes in colon than in others. In colon, ECGF1, DYPD, TYMS, DHFR, FPGS, DUT, BCL2, BAX, and BAK1 except CAD were expressed in the direction that was good response to doxifluridine. These results may provide that colon is a prominent target of doxifluridine and transcriptional profiling is useful to find new targets affecting the response to the drug.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.1-20
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• 2004

Objectives : Based on the analysis of Yin-Yang[음양] characteristics and symptoms, each person is classified into Yin-Yang. Also the validity of the result is statistically analized. Methods : From Feb. to May. 2003, the data were collected through a questionnaire given to 690 patients. The questionnaire was composed of 34 items which were about personality, habit, sweat, response to coldness, thirst, bowel, urine, physical shape, and menstruation for women only. SD(Semantic Differential Technique) used for each item, each item is measured as a contrast of two opposite symptoms. Reliability analysis was used to select items and categories. Based on means of items in each category the Yin-Yang index was developed. The validity of Yin-Yang index was investigated using classification and clustering analysis. In statistical analysis, SPSS V10.0.7 PC was used. Results : The obtained results are summarized as follows: 1) We constructed Yin-Yang index based on the middle point of the sum of categorical means. Then we classified each person into Yin or Yang. 2) To investigate the validity of the distribution of personal Yin-Yang degree, the crosstabulation of results from clustering and classification was used. The hit ratio for classification was much higher than Maximum Chance Criterion($C_{max}$), and concurrence in crosstabulation was successful. Therefore we can infer that the distribution of Yin-Yang was valid. Conclusions : Based on Yin-Yang characteristics and symptoms, we was analyzed personal degree of Yin-Yang, and confirmed the validity of its distribution. Therefore this index can be used further for Bian-Zheng [변증] and classification of the constitution.

• The Journal of Korean Physical Therapy
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• v.21 no.3
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• pp.1-8
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• 2009

Purpose: The purpose of this study was to examine the functional category, the item structure and the model-data fit of the neck disability index (NDI) of neck pain subjects by performing a Rasch rating scale analysis. Methods: The data was obtained from the assessments of 71 college students (males: 27, females: 44) with neck pain. The data of the NDI was applied to the Rasch's rating scale model to estimate the difficulty of items, the goodness-of-fit of each item, the separation reliability and index, and the rating scale. Results: The 'sleep' item showed misfit and nine items were founds to be fits for self-reporting of disability due to neck pain. The most difficult item of the remaining 9 items was 'work' and the easiest item was 'headache'. The transformation formula score=(logit score+7.10)/(7.10+0.11)$\times$100. The 6 response levels of the NDI were validated according to the structure of the rating scale. The item and subject reliability of the separation reliability was 0.97 and 0.85, respectively. Conclusion: We proved that the NDI for self-reporting of disability of daily activities due to mild neck pain was valid and reliable. This study suggests that individuals with mild neck pain may be assessed by using the modified NDI that does not include the 'sleep' item in the 10 items of NDI.

• Journal of Korean Elementary Science Education
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• v.24 no.4
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• pp.351-359
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• 2005

The aims of this research are to analyze elementary preservice teacher's conception and causes of their misconceptions on biological reproduction and inheritance. In future, it would be also to provide useful data for the effective teaching-teaming method in the elementary school as well as opportunities to correct their misconceptions, which help elementary preservice teachers have the appropriate scientific conceptions. Thirty kinds of test questions were designed in science curriculum for elementary students and biology textbook for university students in order to develop reproduction and inheritance's concepts. The questionnaire was given to 166 junior students of university of education in a local city. All statistical analysis was performed using SPSS version 10.0 program. The major results are as follows: Among 30 test questions, 2 questions in plants, 5 questions in animals and 2 questions in gene were appeared as misconceptions over $50\%$. The major reason to hold the misconceptions was influenced by 'learning up to now' category. The selection reasons of response were significantly different between scientific conceptions and misconceptions in 10 questions by analysis of variance. The gender also showed statistically significant differences between scientific conception and misconception in 3 questions by $\chi^2$ test. The selection reasons according to gender were significantly different between male and female students in 5 questions. For the reasons in forming misconceptions, they may cause by stereotype, conscious priority, differences of experiences, interest or attention, lack of professional Knowledge, and so on. Therefore, it was concluded that this research may help elementary preservice teachers to reconsider their conception for reproduction and inheritance and to be successful in science instructions fur elementary students.