• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.867-873
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• 2001

The purpose of this study is to find analytic solution of determining the optimal capacity (lot-size) of multiproduct acyclic multistage production and inventory system to meet the finished product demand under the constraint of finite intermediate storage. Intermediate storage is a practical way to mitigate the material flow imbalance through the line of supply and demand chain. However, the cost of constructing and operating storage facilities is becoming substantial because of increasing land value, environmental and safety concern. Therefore, reasonable decision-making about the capacity of processes and storage units is an important subject for industries. The industrial solution for this subject is to use the classical economic lot sizing method, EOQ/EPQ(Economic Order Quantity/Economic Production Quantity) model, incorporated with practical experience. But EOQ/EPQ model is not suitable for the chemical plant design with highly interlinked processes and storage units because it is developed based on single product and single stage. This study overcomes the limitation of the classical lot sizing method. The superstructure of the plant consists of the network of serially and/or parallelly interlinked non-continuous processes and storage units. The processes transform a set of feedstock materials into another set of products with constant conversion factors. A novel production and inventory analysis method, PSW(Periodic Square Wave) model, is applied to describe the detail material flows among equipments. The objective function of this study is minimizing the total cost composed of setup and inventory holding cost. The advantage of PSW model comes from the fact that the model provides a set of simple analytic solutions in spite of realistic description of the material flows between processes and storage units. the resulting simple analytic solution can greatly enhance the proper and quick investment decision for the preliminary plant design problem confronted with economic situation.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.183-190
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• 2013

In this study, we propose a new CT classification system which is essential factor for strengthening competitiveness of culture contents and technical assistance of convergence contents. For this, we drew particularity of culture contents by reviewing concept and current state of CT. And also we drew problems of existing CT classification systems and implications for applying to future CT classification system by systematic analysis of existing CT classification systems. Through this series of process we developed a new CT classification system applied particularity of culture contents. The suggested CT classification system can embrace all kind of technologies related to all steps of value chain-planning, manufacturing/production, distribution, service- of culture contents. And it has significance having flexibility for government investigation and applying the law and more realistic for industrial site by restructuring of middle classification level.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2705-2709
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• 2012

Objective: To evaluate the predictive value of glutathione S-transferase (GST) gene polymorphisms for the prognosis of osteosarcoma patients receiving chemotherapy. Methods: A total of 159 patients were included in our study between January 2005 and December 2007., with follow-up until January 2012. Genotyping was based upon the duplex polymerase-chain-reaction with the PCR-CTPP method. Results: At the time of diagnosis, 15.4% of the patients presented with metastasis, while 22.3% developed metastasis during follow-up. At the time of final analysis on January 2012, the median follow-up was 45.5 months. Patients with null GSTM1 and GSTT1 had a higher event free survival rate than non-null genotype, but no significant association was found between the two genotypes and prognosis of osteosarcoma. Individuals with GSTP1 Val/Val genotype tended to live shorter than with the IIe/IIe genotype, and we found a significantly higher risk of death from osteosarcoma (adjusted HR=2.35, 95% CI=1.13-4.85). Conclusion: The GSTP1 gene polymorphism may have an important role in the prognosis of osteosarcoma patients with chemotherapy. Further analyses with larger samples and more genes encoding metabolizing and DNA repair enzymes are warranted.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2559-2563
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• 2014

Purpose: We investigated the expression of epithelial $Ca^{2+}$ channel transient receptor potential vanilloid (TRPV) 5 and 6 in non-small-cell lung cancer (NSCLC) and assessed their prognostic role in patients after surgical resection. Materials and Methods: From January 2008 to January 2009, 145 patients who had undergone surgical resection of NSCLCs were enrolled in the study. Patient clinical characteristics were retrospectively reviewed. Fresh tumor samples as well as peritumor tissues were analyzed for TRPV5/6 expression using immune-histochemistry (IHC) and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Patients were grouped based on their TRPV5 and TRPV6 levels in the tumor tissues, followed up after surgery, and statistically analyzed to examine the prognostic roles of TRPV5 and TRPV6 on patients' survival after surgical resection of NSCLCs. Results: Using IHC, among the 145 patients who had undergone surgical resection of NSCLCs, strong protein expression (grade${\geq}2$) of TRPV5 and TRPV6 was observed in a lower percentage of primary tumor tissues than in non-tumor tissues of same patients. Similar findigns were obtained with the RT-PCR test for mRNA levels. Decreased overall mRNA levels of TRPV5 and TRPV6 were associated with a worse overall survival rate (p=0.004 and p=0.003 respectively) and shorter recurrence-free survival (p<0.001 and p<0.001 respectively). The combining effect of TRPV5 and TRPV6 on survival was further investigated using multivariate analysis. The results showed that a combination of low expression of TRPV5 and TRPV6 could be an independent predictor of poor recurrence-free survival (p=0.002). Conclusions: Decreased expression of TRPV5/6 in tumor tissues was observed in NSCLC patients and was associated with shorter median survival time after surgical resection. Combined expression of TRPV5 and TRPV6 in tumor tissues demonstrated promising prognostic value in NSCLC patients.

• Journal of Distribution Science
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• v.15 no.1
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• pp.123-130
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• 2017

Purpose - This research aims to examine the effect of e-business adoption on firm's growth and profitability in the distribution industry. The value added from the distribution industry acts as the cost of other industries. As the distribution industry develops, its stage becomes shorter and the distribution margin becomes smaller. Therefore, e-business is expected to have a different effect on the distribution industry than other industries. Research design, data and methodology - The previous research generally used e-business adoption as an independent variable and firm's performance as a dependent variable. This study elaborated the model using a dynamic panel model that includes the performance variable of the previous year as an independent variable. By employing system GMM (Generalized Method of Moments), the endogeneity problem in the dynamic panel model can be solved. For the analysis, I extracted the distribution companies as the raw data in the National Statistical Office's Business Activity Survey over the period 2006 to 2012. Results - The growth rate of firms adopting e-business was 0.299%p higher than that of the non-adopter. However, only ERP (Enterprise Resource Planning), KMS (Knowledge Management System) and SCM (Supply Chain Management) contributed positively to the growth rate. In the case of profitability, it was 0.04%p higher than the distribution companies that did not adopt e-business. ERP and LMS (Learning Management System) improve profitability, while SCM reduces profitability. Consequently, while ERP improves both growth and profitability, SCM improves growth but reduces profitability. In addition, KMS improves firm's growth only, and LMS does only profitability, showing that each e-business has a differentiated effect. Conclusions - Since the distribution industry has different characteristics from manufacturing and other service industries, the introduction of e-business may not guarantee the growth and profitability of distribution companies. Careful introduction considering the characteristics of the distribution industry is required. In particular, it is necessary to select an e-business meeting the characteristics and needs of a distribution company, and thereafter, it is required for the company's own efforts to internalize it within the system.

• Journal of Digital Convergence
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• v.12 no.12
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• pp.303-311
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• 2014

The accountability of cloud service which provides the cloud users with accountable services applies various technologies such as the compliance of service policy, monitoring and auditing, logging, and others. It ultimately intends to provide trustworthy cloud service by determining who is accountable for various problems happened during data processing and service offering. In this paper, we propose a cloud ecosystem formed from the chain of content and DRM Cloud service in order to offer secure and trust DRM cloud service when providing high value-added content service. Besides this, we analyse the requirements of cloud services for content owners and users and then propose some logging information to be recorded for trace of accountability and a structure of tool for monitoring.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.789-792
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• 2004

In various fields as web mining, bioinformatics, statistical data analysis, and so forth, very diversely missing values are found. These values make training data to be sparse. Largely, the missing values are replaced by predicted values using mean and mode. We can used the advanced missing value imputation methods as conditional mean, tree method, and Markov Chain Monte Carlo algorithm. But general imputation models have the property that their predictive accuracy is decreased according to increase the ratio of missing in training data. Moreover the number of available imputations is limited by increasing missing ratio. To settle this problem, we proposed statistical learning theory to preprocess for missing values. Our statistical learning theory is the support vector regression by Vapnik. The proposed method can be applied to sparsely training data. We verified the performance of our model using the data sets from UCI machine learning repository.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.27-36
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• 2018

Financial IT evaluation methods have been unable to satisfy firms' requirements. There has been a growing demand for more comprehensively and non-financially measuring the IT performance. We developed a process-based approach in evaluating impacts of IT on primary activities. In this research we proposed a model that uses the corporate objective of IT and strategic fitt as the core independent variables in measuring the IT effect. Based on the data collected from the management variables of the 125 companies located in Korea, the companies were classified into the 4 different groups according to their corporate objective for IT: un-oriented, operations oriented, market oriented and dual oriented. Through the empirical analysis, we were able to demonstrate that the management of the companies showing a higher orientation level perceives a better IT investment performance, and this shows that the corporate objective for IT serves as a useful index for measuring the IT investment effect. In this research, it was also demonstrated that the strategic alignment has a positive influence on perceiving the IT investment effect.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.305-310
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• 1996

Five edible mountain vegetables(Saussurea sp. Aster tataricus, A. scaber. Synurus deltoides, Ligularia fischeri) were investigated on the basis of amplified DNA polymorphisms resulted from PCR (polymerase chain reaction) analysis. The sampled plants consisted of 38 individuals in 5 taxa. Only 10 primers out of 62 primers (60 random [10-mer] primers, two 15-mer [M13 core sequence, and (GGAT) sequence]) tested gave rise to polymorphisms in all of the tested plants, producing 176 DAN fragments amplified. Intraspecific polymorphisms found in each taxa showed intraspecies constancy (31.1-61.1%) in the banding patterns of individual plants: Saussurea sp. 31.1%, 15 bands, Aster tataricus, 40.9%, 18 bands, A. scaber. 38.5%, 15 bands. Synurus deltoides, 34.7%, 17 bands, and Ligularia fischeri, 61.1%, 22 brands, respectively. All five species were well classified from each other at the 0.93 level of similarity index value. Intraspecific and interspecific variations were appeared at the levels ranging from 0.62 to 0.99. Based on these results, our PCR analyses support the previous data derived from external morphology of the 5 edible mountain vegetables, but very low levels o intraspecific variations were detected in all of these taxa.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1397-1401
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• 2015

Background: To determine the expressions of Tbx3, a member of subgroup belonging to T-box family, and its prognostic value in pancreatic carcinoma. Materials and Methods: We determined the expression levels of Tbx3 on both mRNA and protein levels in 30 pairs of fresh tumor tissues and paratumor tissues by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, respectively. In addition, protein level of Tbx3 were identified using immunochemistry in 80 pairs of paraffin-embedded specimen. The correlations between Tbx3 expression and various clinicopathological parameters as well as overall survival were evaluated. Results: Tbx3 mRNA and protein levels in tumor tissues were significantly higher than in the paratumor tissues by qRT-PCR ($0.05{\pm}0.007$ vs. $0.087{\pm}0.001$, p<0.001) and western blotting ($1.134{\pm}0.043$ vs. $0.287{\pm}0.017$, p<0.001). The statistical analysis based on immunohistochemical evaluation suggested that Tbx3 aberrant expression was significantly associated with several conventional clinicopathological variables, such as gender, age, tumor position, preoperative CA19-9 level, pathological T staging and N staging. Univariate and multivariate analyses revealed that Tbx3 expression was an independent prognostic factor for overall survival (<0.001). Conclusions: Our results suggest that overexpression of Tbx3 is associated with poor prognosis of pancreatic cancer patients. However, additional clinical trials are needed to accurately validate this observation.