• Journal of Powder Materials
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• v.21 no.1
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• pp.1-6
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• 2014

Medical technologies are gaining in importance because of scientific and technical progress in medicine and the increasing average lifetime of people. This has opened up a huge market for medical devices, where complex-shaped metallic parts made from biocompatible materials are in great demand. Today many of these components are already being manufactured by powder metallurgy technologies. This includes mass production of standard products and also customized components. In this paper some aspects related to metal injection molding of Ti and its alloys as well as modifications of microstructure and surface finish were discussed. The process chain of additive manufacturing (AM) was described and the current state of the art of AM processes like Selective Laser Melting and electron beam melting for medical applications was presented.

• Journal of the Korean Statistical Society
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• v.36 no.1
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• pp.129-148
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• 2007

Frailty estimates from the proportional hazards frailty model often lead us to conjecture the heterogeneity in frailty such that the variance of the frailty varies over different covariate groups (e.g. male group versus female group). For such systematic heterogeneity in frailty, we consider a regression model for the variance components in the proportional hazards frailty model, denoted by the MLFM. However, in many cases, the observed data do not show any statistically significant preference between the homogeneous frailty model and the heterogeneous frailty model. In this paper, we propose a Bayesian model averaging procedure with the reversible jump Markov chain Monte Carlo which selects the appropriate model automatically. The resulting regression coefficient estimate ignores the model uncertainty from the frailty distribution in view of Bayesian model averaging (Hoeting et al., 1999). Finally, the proposed model and the estimation procedure are illustrated through the analysis of the kidney infection data in McGilchrist and Aisbett (1991) and a simulation study is implemented.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.357-367
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• 2021

In general, common cause failures (CCFs) have been modeled with the assumption that components within the same group are symmetric. This assumption reduces the number of parameters required for the CCF probability estimation and allows us to use a parametric model, such as the alpha factor model. Although there are various asymmetric conditions in nuclear power plants (NPPs) to be addressed, the traditional CCF models are limited to symmetric conditions. Therefore, this paper proposes the copulabased CCF model to deal with asymmetric as well as symmetric CCFs. Once a joint distribution between the components is constructed using copulas, the proposed model is able to provide the probability of common cause basic events (CCBEs) by formulating a system of equations without symmetry assumptions. In addition, Bayesian inferences for the parameters of the marginal and copula distributions are introduced and Markov Chain Monte Carlo (MCMC) algorithms are employed to sample from the posterior distribution. Three example cases using simulated data, including asymmetry conditions in total failure probabilities and/or dependencies, are illustrated. Consequently, the copula-based CCF model provides appropriate estimates of CCFs for asymmetric conditions. This paper also discusses the limitations and notes on the proposed method.

• YAKHAK HOEJI
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• v.18 no.3
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• pp.217-227
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• 1974

It was established that .alpha.-spinasterol (I) was isomerized by hydrogen chloride to a mixture of two isomers. These isomers were separated into each of components and identified as .DLETA.$^{8(14),22}$ -stigmastadienol (III) and ${\delta}$$^{14,22}$ -stigmastadienol (IV), respectively. The mass spectra of these compounds were found to be particularly suitable to idetify the position of nuclear double bond of sterols possessing 22 : 23 -double bond in side chain.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.40-40
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• 1999

We propose a method where interaction energies and force components are calculated separately for each residue of biomolecules. It is found that the correlation factors obtained from the analysis of five types of force terms and one interaction energy term (main chain self-energy) can be used to predict a mutants free energy difference relative to wild type.(omitted)

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.409-410
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• 2006

New applications for PM have resulted in a substantial market growth during the last decades. The clue to these components lies in the utilization of new powders and component production processes. In order to reduce development time and increase the probability for success it is essential to work in close cooperation within the whole chain from powder supplier to component supplier and component user.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.498-498
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• 2003

Sphingolipids are important structural components of the stratum corneum lipids and serve the epidermal permeability barrier function. Recent investigations on biological activities of sphingolipids have revealed that they have a number of important biological functions in the cell such as cell proliferation and differentiation, anti-inflammation, mediation of signal transduction and many more.(omitted)

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.15-21
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• 2020

E-commerce live broadcast is a new online shopping model that has gradually emerged in China in recent years. In the e-commerce live broadcast, the audience gathered into a buying group by watching and participating in virtual interaction, and obtained stable emotional energy from it. Closely following the concept of emotional energy, with the help of the interaction ritual chain model, the components of e-commerce live broadcast can be clarified. And the paper shows how individuals can form a buying group in social interaction. I will take the interaction behavior in e-commerce live broadcast as the research object and observe the phenomenon based on the theory of interaction ritual, then come up with the interaction ritual chain model of E-commerce live broadcast group.

• Journal of Information Technology Services
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• v.11 no.3
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• pp.67-87
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• 2012

These days, firms are focusing on the improvement of relationships with business partners. The supply chain integrations are taking critical role in improving the relationships with business partners. In accordance with the development of the IT technology, it became possible for firms not only to integrate inner parts of the organization, but also to integrate the company with other organizations in the supply chain, which is open system. Therefore, in e-Biz environments, it is imperative for firms to strengthen the core capacity through the supply chain integration, and to precisely determine the components of the determinants of e-Business integration which impact the firm performance. This study analyzed determinants that have impacts on business integration in IT capacity perspectives in competetive environments. We analyzed 163 domestic companies to find out many significant suggestive points. First, IT management capacity, process innovation capacity are adopted as determinants of differentiation and competetive edges against competing firms. Second, it is analyzed that the more the companies are in intensified competetive environment, the more likley that the innovation capacity and partner management capacity become the determinants of the business integration of the companies and that they pursue new market development strategy. Third, it is analyzed that the more the companies are in high demand fluctuation, the more likley that the innovation capacity becomes the determinants of the business integration of the companies, and that they pursue new market development strategy and operation efficiency strategy. Last, it is analyzed that the more the companies are Technology dependent, the more likely that IT management capacity and process innovation capacity become the determinants of business integration, and that they pursue new market development strategy and operation efficiency strategy. These results provide us the foundation that the determinants that we have analyzed can impact the supply chain integration strategies which take into account the competetive environments.

• Journal of Forest and Environmental Science
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• v.34 no.4
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• pp.304-312
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• 2018

This study investigates to identify the impact factors of timber production cost on the relationship between production cost components and revenues generated by evaluating the entire timber supply chain. In this research, selected 13 logging zones as target areas and classified 14 forest production cost factors, six groups. Additionally, established 13 externalenvironmental factors with related stakeholders and forestry experts. And the BCR (Benefit Cost Ratio) method was then used to analyze the economics of each zone. Filled up a checklist and rated using 5 point scale for each target region, and extracted major cost factors for the production economy of the item. The analysis of major cost factors in the timber production revealed that wood grab equipment usage fee was the first ranked and forest trees purchase cost was ranked in the $2^{nd}$Also, the $3^{rd}$ranking was logging expenses, and transport cost, which accounted for 84% of the total cost, was ranked in the $4^{th}$. In addition, the rock land ratio, slope, timber payment (forest trees purchase cost), special timber, ratio of timber, DBH (Diameter at Breast Height), and mixed forest ratio were the factors that most affected the timber supply chain cost.