• International Journal of Vascular Biomedical Engineering
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• v.2 no.2
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• pp.16-26
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• 2004

The object of this study is to develop a mathematical model of the hemodialysis system including the mechanism of solute kinetics, water exchange and also cardiovascular dynamics. The cardiovascular system model used in this study simulates the short-term transient and steady-state hemodynamic responses such as hypotension and disequilibrium syndrome (which are main complications to hemodialysis patients) during hemodialysis. It consists of a 12 lumped-parameter representation of the cardiovascular circulation connected to set-point models of the arterial baroreflexes, a kinetic model (hemodialysis system model) with 3 compartmental body fluids and 2 compartmental solutes. We formulate mathematically this model in terms of an electric analog model. All resistors and most capacitors are assumed to be linear. The control mechanisms are mediated by the information detected from arterial pressoreceptors, and they work on systemic arterial resistance, heart rate, and systemic venous unstressed volume. The hemodialysis model includes the dynamics of urea, creatinine, sodium and potassium in the intracellular and extracellular pools as well as fluid balance equations for the intracellular, interstitial, and plasma volumes. Model parameters are largely based on literature values. We have presented the results on the simulations performed by changing some model parameters with respect to their basal values. In each case, the percentage changes of each compartmental pressure, heart rate (HR), total systemic resistance (TSR), ventricular compliance, zero pressure filling volume and solute concentration profiles are represented during hemodialysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.192-200
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• 2010

Korea is part of a region of low or moderate seismic zone in which few earthquakes have been monitored, so it is difficult to approve design ground motions and seismic responses on structures from response spectrum. In this study, a series of dynamic centrifuge model tests for demonstrating seismic amplification characteristics in soil-foundation-structure system were performed using electro-hydraulic shaking table mounted on the KOCED 5.0 m radius beam centrifuge at KAIST in Korea. The soil model were prepared by raining dry sand and $V_S$ profiles were determined by performing bender element tests before shaking. The foundation types used in this study are shallow embedded foundation and deep basement fixed on the bottom. Total 7 building structures were used and the response of building structures were compared with response spectrum from the acceleration records on surface.

• The Journal of Information Systems
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• v.19 no.4
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• pp.51-63
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• 2010

U-City applies ubiquitous information technologies such as RFID, GPS, USN to various components of city functions and services. The concept of U-City was popularized especially in Korea and currently more than 40 projects have been carrying out all over country. U-City incorporates advanced information communication technologies into ubiquitous information services to provide better quality of life. The purpose of this study is to analyze preferences for the U-City services by surveying experts in U-City developing companies. This study employs Analytic Hierarchy Process which is very useful tool for performing multi-criteria decision making. Total of 28 responses were used in the analysis. The results indicated that the first 7 most preferred items were from transportation and safety area and environment and healthcare area and 4 out of 6 items in transportation and safety area were ranked among them. It implies that respondents consider countering anxiety caused by congested traffic, natural disasters, crimes, etc most important aspect that U-City should deal with. On the other hand, U-Port, U-Convention, U-Logistics, U-Public Administration and U-City Portal were listed as the least preferred services.

• Korean Institute of Interior Design Journal
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• v.27 no.3
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• pp.116-125
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• 2018

With rapid economic development in Korea, interests in interior design have increased gradually. However, interior design markets were poorly evaluated from 2015 Korean Consumer Evaluation. It is necessary to identify what kinds of problems, defects, and consumer claims have arisen during interior design planning and construction procedures. Therefore the purpose of this study is to investigate claims and disputes in interior design project procedures and to find out when defects or claims take place in those procedures in order to reduce claims or defects. Email questionnaires were distributed to KOSID members (professional interior designers) using Google Survey. In addition, a focus group interview was conducted. A total of 54 responses were collected and analyzed using SPSS 19. As a result, in an agreement stage, alteration in materials is the major source of claim. More than a half of respondents addressed time shortage for programming and planning. During the construction stage, approximately 31% respondents experienced client dissatisfaction with materials and finishes. The reason for project completion delay was due to claims during construction. The claims most frequently appealed by clients were related to painting. The satisfaction with project quality is positively related to the quality and contents of design documents including design drawings and specifications. Regulations and communication with clients are important issues to reduce the gaps between interior designers and clients/ consumers.

• Knowledge Management Research
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• v.15 no.4
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• pp.79-103
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• 2014

This research investigates whether product types moderate the relationship between e-tailer characteristics and shopping attitudes in the context of online category killer stores. To identify the antecedents of consumer attitudes for category killer stores, the product types are characterized by the two dimensions of hedonic and utilitarian. A total of 268 responses were collected from consumers who experienced online category killer stores. The results show that the quality of information contained in a website, customer review, relational benefits, and the expertise of the e-tailer are important determinants for shopping attitudes of consumers. Regarding the moderating effects of product types, hedonic value significantly moderates the relationships between shopping attitudes and relational benefits/e-tailer expertise. However, utilitarian value does not significantly moderate the relationships between shopping attitudes and any of the e-tailer characteristics. Theoretical contributions of this study are the findings of moderating effects of hedonic value on the relationships between e-tailer characteristics and shopping attitudes. In addition, this study practically implies how companies can utilize these characteristics strategically for marketing and the selection of products.

• The Journal of Korean Medicine
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• v.22 no.1
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• pp.3-9
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• 2001

In the view of oriental medicine, the liver is the general of the army in its function of protecting against the enemy. So this concept is very closely associated to the immunological function. Its relations with immunological function are as follows. 1. The liver produces most of the proteins and converts them with hepatocytes, composes 80% in total reticuloendothelial system with Kuffer cells & endothelial cells and has typical structure of sinusoidal vessels closely related with the blood system. 2. The liver plays an important role in innate immunity with Kuffer cells as well as with the molecules that the liver produces, related to complementary systems. 3. In the embryonic period, the liver is associated with immune associated cell growth and their maturation. After birth, it is associated with removing old red blood cells and with systematically modulating immune system through hormone metabolism. 4. The liver controls the autoimmune disease resulting from immune complex by removing molecules like immune complex. 5. In the processing of blood 19A from the digestive system, the liver has an important role in protecting the body from unnecessary immune responses. 6. In the oriental medical view, liver plays a major role in the immune function by storing blood and dispersing stagnated hepatoqi with the help of the kidneys and spleen.

• Journal of the Korean Operations Research and Management Science Society
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• v.40 no.3
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• pp.97-117
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• 2015

There has been a lack of research that has addressed firm performance associated with the mechanism among dependence, conflict and cooperation in the context of B2B relationships. Building on current knowledge regarding key constructs of dependence, conflict, and cooperation, the authors examine the primary assumption underlying firm performance and presents a process model of key constructs on firm performance using two moderators (relationship length and firm type). In so doing, a professional online research firm conducts panel survey and a total of 200 responses are used to test our proposed model. The results show that both conflict-cooperation and cooperation-firm performance linkages are significant, but other proposed links are insignificant. While the moderating effect of firm type is not significant, the dependence-performance link is moderated by relationship length, particularly in the stage of the initial relationships. These results has implications for a better understanding of B2B relationships from the initial stage to the sustainable stage.

• BMB Reports
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• v.34 no.3
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• pp.278-283
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• 2001

Antioxidant and redox enzyme activities are known to be involved in the cellular responses to various stresses. Their variations were observed according to the growth cycle of the fission yeast Schizosaccharomyces pombe. Peroxidase activity appeared to be notably higher in the early exponential phase than in the mid-exponential and stationary phases. However, catalase activity showed a variation pattern resembling the growth curve. Glutathione S-transferase activity was higher in the early exponential and late stationary phases. Activities of the two redox enzymes, thioredoxin and thioltransferase (glutaredoxin), were high in the stationary phase. However, their activities appeared to increase from the early exponential to mid-exponential phase. Total glutathione content had a varying pattern similar to that of thioredoxin and thioltransferase. However, its content in the early exponential phase was high. These results propose that antioxidant and redox enzymes tested are also involved in the mechanism of cell growth.

• BMB Reports
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• v.50 no.2
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• pp.55-57
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• 2017

Toll-like receptor 4 (TLR4) together with MD2, one of the key pattern recognition receptors for a pathogen-associated molecular pattern, activates innate immunity by recognizing lipopolysaccharide (LPS) of Gram-negative bacteria. Although LBP and CD14 catalyze LPS transfer to the TLR4/MD2 complex, the detail mechanisms underlying this dynamic LPS transfer remain elusive. Using negative-stain electron microscopy, we visualized the dynamic intermediate complexes during LPS transfer-LBP/LPS micelles and ternary CD14/LBP/LPS micelle complexes. We also reconstituted the entire cascade of LPS transfer to TLR4/MD2 in a total internal reflection fluorescence (TIRF) microscope for a single molecule fluorescence analysis. These analyses reveal longitudinal LBP binding to the surface of LPS micelles and multi-round binding/unbinding of CD14 to single LBP/LPS micelles via key charged residues on LBP and CD14. Finally, we reveal that a single LPS molecule bound to CD14 is transferred to TLR4/MD2 in a TLR4-dependent manner. These discoveries, which clarify the molecular mechanism of dynamic LPS transfer to TLR4/MD2 via LBP and CD14, provide novel insights into the initiation of innate immune responses.

• Fashion & Textile Research Journal
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• v.14 no.2
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• pp.242-250
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• 2012

This study investigates the benefits consumers seek in buying and using bedding, sub-dimensions of lifestyle, and the relationship between those of the benefits and the dimensions of lifestyle. This study conducted a survey to verify benefits consumers seek in buying bedding. A questionnaire was developed to collect data to measure lifestyle, benefits sought for the bedding, and demographic variables. Research was conducted on married women aged between 20 and 59. Total 294 responses were analyzed using factor analysis, correlation analysis, t-test, and one-way ANOVA with SPSS 18.0. A factor analysis identified three dimensions of benefits sought for the bedding: utilitarian benefits, social benefit, and aesthetic benefit. Lifestyle consists of five dimensions: health seeking, social symbol seeking, leisure/country-living seeking, aesthetics seeking, and economy seeking. All dimensions underlying benefits consumers seek in buying bedding and all dimensions of lifestyle were correlated. As consumers get older, they tend to seek more utilitarian and social/psychological benefits of bedding.