• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.263-272
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• 2016

Electronic structure calculations have become a powerful foundation for computational materials engineering. Four major factors have enabled this unprecedented evolution, namely (i) the development of density functional theory (DFT), (ii) the creation of highly efficient computer programs to solve the Kohn-Sham equations, (iii) the integration of these programs into productivity-oriented computational environments, and (iv) the phenomenal increase of computing power. In this context, we describe recent applications of the Vienna Ab-initio Simulation Package (VASP) within the MedeA$^{(R)}$ computational environment, which provides interoperability with a comprehensive range of modeling and simulation tools. The focus is on technological applications including microelectronic materials, Li-ion batteries, high-performance ceramics, silicon carbide, and Zr alloys for nuclear power generation. A discussion of current trends including high-throughput calculations concludes this article.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.44-46
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• 2001

This paper describes the use of the PHOENICS CFD package for the simulation of the high-current period of the arcing process in a hybrid rotating arc/auto expansion by interrupter. The operating principle of this device depends on rapid arc rotation due to the magnetic field created by the fault current through a coil which is mounted on contacts and also relies on the principle of thermal expansion created by arc energy in extinguishing chamber and finally causes pressure rise in expansion volume. This paper is divided into three main sections. The first gives a brief overview of the interrupter. The second section gives a full description of the methods used in the calculation. The final section presents some sample results for the hybrid interrupter.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.1156-1157
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• 2013

The mobile application market has been growing extensively in recent years. Currently, Apple's App Store has more than 400,000 applications and Google's Android Market has above 150,000 applications. Such growth in volumes of mobile applications has created a need to develop a recommender system that assists the users to take the right choice, when searching for a mobile application. In this paper, we study the recommendation system building tools based on collaborative filtering. Specifically, we present a study on comparison analysis of collaborative filtering in Java and R statistical software. We implement the collaborative filtering using Java's Apache Mahout and R's recommenderlab package. We evaluate both methods and describe the advantages and disadvantages of using them in order to implement collaborative filtering.

• Journal of Preventive Medicine and Public Health
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• v.55 no.2
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• pp.116-124
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• 2022

Epidemiological studies typically examine the causal effect of exposure on a health outcome. Standardization is one of the most straightforward methods for estimating causal estimands. However, compared to inverse probability weighting, there is a lack of user-centric explanations for implementing standardization to estimate causal estimands. This paper explains the standardization method using basic R functions only and how it is linked to the R package stdReg, which can be used to implement the same procedure. We provide a step-by-step tutorial for estimating causal risk differences, causal risk ratios, and causal odds ratios based on standardization. We also discuss how to carry out subgroup analysis in detail.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.1
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• pp.387-394
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• 2019

Recently, the importance of big data has been increased, and demand for data analysis for the big data is also increased. R language is developed for data analysis, and users are analyzing data by using algorithms of various statistics, machine learning and data mining packages in R language. However, it is difficult to develop an application using R. Early study proposed a method to call R script through another language such as PHP, Java, and so on. However, it is troublesome to write such a development method in addition to R in combination with other languages. In this study, we introduce how to write API using only R language without using another language by using Plumber package. We also propose a solution for security issues related with R API. If we use propose technology for developing web application, we can expect high productivity, easy of use, and easy of maintenance.

• Journal of Korean Academy of Nursing
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• v.39 no.4
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• pp.480-489
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• 2009

Purpose: The purpose of this study was to identify the factors which influence health-related quality of life (HRQoL) in Korean Medicaid beneficiaries. The relationships among sociodemographic factors, health status, health behavior, and HRQoL were analyzed. Methods: Data from the 2007 survey on Health Services Use and Health Status of Medicaid Beneficiaries conducted by the Ministry for Health Welfare and Family Affairs were examined. To analyze the sample survey data, descriptive statistics, correlation and hierarchical multiple survey regression analysis with SAS 9.1.3 package were used with SURVEYMEANS and SURVEYREG procedures, which incorporate the sample design into the analyses in order to make statistically valid inference for the whole Medicaid population. Results: The HRQoL correlated with limitations in Activities of Daily Living (ADL) (r=-.509, p<.001), stress (r=-.387, p<.001), depression (r=-.385, p<.001), alcohol consumption (r=.216, p<.001), and exercise (r=.293, p<.001). Significant factors that affect HRQoL of Medicaid beneficiaries were gender, region, limitations in ADL, stress, depression, alcohol consumption, and regular exercise. These variables explained 44.6% of HRQoL (F= 215.00, p<.001). Conclusion: The results indicate that to improve the HRQoL of Medicaid beneficiaries it is important to develop nursing intervention programs that focus on psychological health and health behavior and to give consideration to differences in gender and region.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.7
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• pp.339-342
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• 2005

We present a new high-frequency equivalent circuit model for 52pin QFP used in typical IC's and extract R, L, and C values of this circuit model using a 3-D E & M field simulator. Futhermore, L and C value variations as a function of Pin number due to the shape differences of the leads have been fitted to 2nd order polynomials in order to extend the applicability of this model.

• Journal of applied mathematics & informatics
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• v.5 no.2
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• pp.293-300
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• 1998

The numerical method is used to solve the Fredholm integral equation of the second kind with weak singular kernels using the Toeplitz matrices. The solution has a computing time requir-ment of O(N2) where 2N+1 is the number of discretization points used. Also the error estimate is computed. Some numerical Exam-ples are computed using the Mathcad package.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.107-115
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• 2003

The present paper deals with the mulberry cultivation technology with package of practices for successful sericulture in Indian sub-tropics. The information on leaf nutritional quality in trained and untrained trees is provided. Besides, the current status of sericultural practices is discussed based on the problems faced by the industry and intensive field surveys undertaken in different areas of one of the most potential sericultural provinces.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.09a
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• pp.3-17
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• 2003

.Package Trend -> Memory : Lighter, Thinner, Smaller & High Density => SiP, 3D Stack -> MPU : High Pin Counts & Multi-functional => FCBGA .Interposer Trend -> Via - Unfilled Via => Filled Via - Staggered Via => Stacked Via -> Emergence of All-layer Build-up Processes -> Interposer Material Requirement => Low CTE, Low $D_{k}$, Low $D_{f}$, Halogen-free .New Technology Concept -> Embedded Passives, Imprint, MLTS, BBUL etc.