• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1187-1192
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• 2008

In this paper, a versatile multi-objective optimization concept for fatigue life prediction is introduced. Multi-objective decision making in engineering design refers to obtaining a preferred optimal solution in the context of conflicting design objectives. Compromise decision support problems are used to model engineering decisions involving multiple trade-offs. These methods typically rely on a summation of weighted attributes to accomplish trade-offs among competing objectives. This paper gives an interpretation of the decision parameters as governing both the relative importance of the attributes and the degree of compensation between them. The approach utilizes a response surface model, the compromise decision support problem, which is a multi-objective formulation based on goal programming. Examples illustrate the concepts and demonstrate their applicability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.275-278
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• 1998

In recent years, miniaturization has become the key factor in the development of mobile communication system. Portable communications and computing devices suffer from two conflicting requirements which are device size to be as small as possible and large, high resolution display. These problems can be solved by virtual display. Any display in which the user views an image through an optical system is a virtual display. It provides a display which is high resolution, appears large to the viewer and at the same time occupies little physical space. In this study, handhold units of mobile communication was investigated through use of the SLA(Scanned Linear Array). The basic SLA mechanism comprises a linear array of LED's, a magnifying lens, and a scan mirror. To optimize virtual image, we investigated optical system design and operating condition for each part.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.63
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• pp.1-12
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• 2001

When designing the parameter on the multiple quality characteristics, there has been a study for optimization of problems, but there has been few former study on the possible conflicting phenomena in consideration of the correlations among the characteristics. To solve the issue on the optimal design for multiple quality characteristics, this study propose the expected loss function with cross-product terms among the characteristics and derived range of the coefficients of the terms. The model will be used to determine the global optimal design parameters where there exists the conflict among the characteristics, which shows difference in optimal design parameters for the individual characteristics. Also, when an adjustment factor exists for each m performance characteristics, this research propose a method by minimizing the expected loss after adjustment.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.707-708
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• 2009

In this paper, we provide a tradeoff solution to two conflicting requirements in VANET; Privacy and Aggregation. The information about traffic density is an important factor of aggregation in VANET. In our proposed scheme, densely located Road-Side Units (RSU) perform traffic density calculation and then aggregate the traffic information extracted from beacons received from the vehicles. RSUs then disseminate the aggregated traffic information to all the vehicles and neighbor RSUs. We use identityless beaconing thereby providing privacy and we do not consider the content security of beacons. We show that our scheme provides privacy in the case of aggregation, which has not been considered in previous schemes.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5753-5757
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• 2014

Background: The purpose of this study is to determine whether the IGF1R expression has a prognostic role in non-small cell lung cancer. Materials and Methods: Forty-seven patients histopathologically diagnosed with small cell lung cancer upon bronchoscopic biopsy or resection materials were included in the study. IGF1R expression was examined via immunohistochemical methods. In samples, >10% staining were assessed as positive and ${\leq}10%$ as negative. Information about demographic datas and treatments was obtained by retrospective searches of patient files. Results: IGF1R expression was determined as positive in 38 (80.9%) and as negative in 9 (19.1%) patients. There was no significant relation between IGF1R expression and histological sub-type, local invasion, lymph node and metastasis status (p=0.842, p=0.437, 0.064, 0.447, respectively). There was also no correlation with IGF1R expression and survival (p=0.141). Conclusions: There are conflicting results between IGF1R and its prognostic effects in the various studies. It has been claimed in some studies it is not related to prognosis as in our study, and in some studies it has been claimed that it is a good prognostic factor whereas in some studies it has been claimed as being a factor for worse prognosis. We think that IGF1R expression in non-small cell lung carcinoma patients deserves further analysis, because of its potential prognostic and predictive roles.

• BMB Reports
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• v.57 no.2
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• pp.98-103
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• 2024

The mammalian sirtuin family (SIRT1-SIRT7) has shown diverse biological roles in the regulation and maintenance of genome stability under genotoxic stress. SIRT7, one of the least studied sirtuin, has been demonstrated to be a key factor for DNA damage response (DDR). However, conflicting results have proposed that Sirt7 is an oncogenic factor to promote transformation in cancer cells. To address this inconsistency, we investigated properties of SIRT7 in hepatocellular carcinoma (HCC) regulation under DNA damage and found that loss of hepatic Sirt7 accelerated HCC progression. Specifically, the number, size, and volume of hepatic tumor colonies in diethylnitrosamine (DEN) injected Sirt7-deficient liver were markedly enhanced. Further, levels of HCC progression markers and pro-inflammatory cytokines were significantly elevated in the absence of hepatic Sirt7, unlike those in the control. In chromatin, SIRT7 was stabilized and colocalized to damage site by inhibiting the induction of γH2AX under DNA damage. Together, our findings suggest that SIRT7 is a crucial factor for DNA damage repair and that hepatic loss-of-Sirt7 can promote genomic instability and accelerate HCC development, unlike early studies describing that Sirt7 is an oncogenic factor.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3169-3173
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• 2013

Background: Findings from previous published studies regarding the association of the XRCC3 Thr241Met polymorphism with glioma susceptibility have often been conflicting. Therefore, a meta-analysis including all available publications was carried out to make a more precise estimation of the potential relationship. Methods: By searching the electronic databases of Pubmed and Embase (up to April 1st, 2013), a total of nine case-control studies with 3,752 cases and 4,849 controls could be identified for inclusion in the current meta-analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the strength of the association. Results: This meta-analysis showed the XRCC3 Thr241Met polymorphism to be significantly associated with decreased glioma risk in the allelic model (Met allele vs. Thr allele: OR= 0.708, 95%CI= 0.631-0.795). Moreover, we also observed a statistically significant association between the XRCC3 Thr241Met polymorphism and reduced glioma risk in analyses stratified by ethnicity (Asian) and source of controls (hospital based) in the allelic model. Conclusions: Current evidence suggests that the XRCC3 Thr241Met polymorphism may be a risk factor for glioma development, especially in Asians.

• Journal of Technology Innovation
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• v.4 no.1
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• pp.1-26
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• 1996

Traditional studies of new venture performance have focused on the characteristics of entrepreneurs and have shown conflicting results on the relationship between the characteristics and performance of new ventures. Recently, some researchers have broadened their search to include aspects of the industry and the strategy of new ventures. The purposes of this study are to identify wtrategic archetypes of new ventures based on the taxonomic approach and to explain the differences in new venture characteristics and performance among strategic archetypes. To find the strategic archetypes, 114 new venture CEOs from various industries were asked to describe their ventures' competitive strategy through 19 questionnaire items on competitive methods. Using factor analysis and subsequent cluster analysis, four archetypes were identified such as : versatile type, technology-driven type, market-oriented type, and cost reduction type. The results imply that there exist different types of venture strategy even among new technology-based venture firms in Korea, and show the differences in performance among strategic archetypes: market-oriented type and versatile type are better than cost reduction type in terms of growth rate and profitability. Because the venture strategy in identified as a major determinant of the venture performance in this study, the choice of venture strategy suitable for firm's industrial characteristics and internal resource bases becomes a very strategic decision for firm's sustained growth. Further studies are needed to strengthen some methodological limitations of the study.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.362-379
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• 2015

In this study, Nuclear Power Plant (NPP) construction schedule delay risk assessment methodology is developed and the construction delay risk is assessed for turnkey international NPP projects. Three levels of delay factors were selected through literature review and discussions with nuclear industry experts. A questionnaire survey was conducted on the basis of an analytic hierarchy process (AHP) and Relative Importance Index (RII) methods and the schedule delay risk is assessed qualitatively and quantitatively by severity and frequency of occurrence of delay factors. This study assigns four main delay factors to the first level: main contractor, utility, regulatory authority, and financial and country factor. The second and the third levels are designed with 12 sub-factors and 32 sub-sub-factors, respectively. This study finds the top five most important sub-sub-factors, which are as follows: policy changes, political instability and public intervention; uncompromising regulatory criteria and licensing documents conflicting with existing regulations; robust design document review procedures; redesign due to errors in design and design changes; and worldwide shortage of qualified and experienced nuclear specific equipment manufacturers. The proposed combined AHP-RII methodology is capable of assessing delay risk effectively and efficiently. Decision makers can apply risk informed decision making to avoid unexpected construction delays of NPPs.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.95-107
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• 2020

This study analyzes the effect of corporate social responsibility (CSR) activity on investors' heterogeneous beliefs. The hypothesis of this study is based on the conflicting effects of CSR activities on firm value and earning's quality. Investors' heterogeneous beliefs used in the empirical analysis of this study are trading volume, and CSR activity is measured by the KEJI Index (Korea Economic Justice Institute Index). This study performs an empirical analysis using regression analysis including control variables. CSR activities are found to have a positive relationship with trading volume. This is consistent regardless of the low and high accounting information (earning's quality). It can be interpreted that Korea's CSR activity acts as an incentive to increase investors' heterogeneous beliefs about target companies. In other words, it implies that the investor judges CSR activities negatively when evaluating firm value. This study could have a policy implication in that it analyzes how CSR activities affect investors' decision-making. In other words, this study analyzed CSR activities from the perspective of shareholders. Therefore, this study is expected to provide useful information for policymaking by regulatory agencies. In particular, its contribution is to presents data that CSR activities can be a negative factor in evaluating firm values.