• Steel and Composite Structures
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• v.20 no.2
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• pp.251-266
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• 2016

The paper combines two distinct parts. First the behavior of welded headed studs with small diameters of 10 and 13 mm acting as shear connectors (which are not embraced in current standards) is studied. Based on standard push tests the load-slip relationships and strengths are evaluated. While the current standard (Eurocode 4 and AISC) formulas used for such studs give reasonable but too conservative strengths, less conservative and full load-slip rigidities are evaluated and recommended for a subsequent investigation or design. In the second part of the paper the partially encased beams under bending are analyzed. Following former experiments showing rather indistinct role of studs used for shear connection in such beams their role is studied. Numerical model employing ANSYS software is presented and validated using former experimental data. Subsequent parametric studies investigate the longitudinal shear between steel and concrete parts of the beams with respect to friction at the steel and concrete interface and contribution of studs with small diameters required predominantly for assembly stages (concreting). Substantial influence of the friction and effect of concrete confinement was observed with rather less noticeable contribution of the studs. Distribution of the longitudinal shear and its sharing between friction and studs is presented with concluding remarks.

• The Transactions of the Korean Institute of Power Electronics
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• v.15 no.4
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• pp.327-334
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• 2010

This paper deals with a single-phase dynamic voltage restorer(DVR) with a quasi Z-source topology. The proposed system based on a single-phase quasi Z-source PWM ac-ac converter which have features such as the input voltage and output voltage are sharing ground, and input current operates in continuous current mode(CCM). For the detection of voltage sag-swell, peak voltage detection method is applied. Also, the circuit principles of the proposed system are described. During the 60% severe voltage sag and 30% voltage swell, the proposed system controls the adding or missing voltage and maintains the rated voltage of sinusoidal waveform at the terminals of the critical loads. Finally, PSIM simulation and experimental results are presented to verify the proposed concept and theoretical analysis.

• Journal of Yeungnam Medical Science
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• v.18 no.1
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• pp.1-12
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• 2001

Liver transplantation is widely accepted as an effective therapeutic modality for a variety of irreversible acute and chronic liver diseases for which no satisfactory therapy is available. Following the first unsuccessful efforts at human liver transplantation in 1963, development of the procedure evolved at first slowly and steadily for 20 years and then rapidly over the past two decades. The growth of liver transplantation was facilitated by the conclusion of the national institutes of health consensus development conference in 1983 that liver transplantation is not an experimental procedure but an effective therapy that deserves broader application. The number of liver transplantations increased 2.4-fold(from 1.713 to 4.058) from 1988 to 1996. but the number of patients on the UNOS(united network of organ sharing) liver list increased 12.1-fold(from 616 to 7,467); as would be expected, the number of deaths of listed patients increased 4.9-fold(from 195 to 954), The current supply of donor livers is insufficient to meet this need, and organ donation has been stagnant or increased by only a few percent in recent years. These facts underscore the importance of the appropriate selection of candidates for liver transplantation and the development of operative procedures, such as living donor liver transplant, split liver transplant and auxiliary partial liver transplant.

• Journal of Korean Library and Information Science Society
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• v.44 no.4
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• pp.45-70
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• 2013

This survey is performed to propose the direction of policy development on reading education for Jeollabukdo Office of Education. To do this, this survey asked 239 teachers who are in charge of each school's reading education. The questionnaire is designed to investigate the effectiveness of current support projects from Jeollabukdo Office of Education, current level of schools' reading education and priorities of policy development. The findings of this survey are as follows: The teachers are contented with current support projects. Each school provides an average of 4 reading programs per year. Elementary schools' level of reading education is higher than middle and high schools' level. And more employment of full time reading experts as teacher librarian and the improvement of school libraries are revealed to be more important priorities on the policy development of reading education. Based on these findings, this study proposed maintenance of current support projects, improvement of school libraries, development of specialized policies for elementary schools, enhancement of reading teachers' expertise and preparation of information sharing system as the direction of policy development.

• Journal of the military operations research society of Korea
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• v.29 no.2
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• pp.45-60
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• 2003

As we live in real If era, If become a mandatory component for nations and organizations to survive in severe competition. If is also thought of as strategic asset for effective business operations, yet there is no proved statement on the interoperability and system integration which causes serious problem in terms of requirement engineering among current systems. The National Defense Enterprise Architecture Framework is a strategic information asset base, which define the military operation activities for the mission, the information necessary for military operations, the technologies necessary for implementing new technology in response to changing operational needs. It is an integrated model or representation. Information Systems will be evolved by the National Defense Enterprise Architecture framework. The purpose of this framework is to present overall picture of national defense information system domain so that information systems are interoperated, integrated and information sharing is increased among affiliated organization of Defense Military.

• Journal of Digital Convergence
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• v.6 no.3
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• pp.23-34
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• 2008

Progressing of Web2.0 and social digitalization are lead to changing citizens participation and citizen centric service of civic service. To meet this trends that is online collaboration and sharing, citizen's service that provides our government, also need to changing web2.0 style. This paper argues that government could now grasp the opportunities that are emerging in terms of web2.0 Current policy and action is not yet adequate to grasp these opportunities. So this study focused on strategies of civil services based on web2.0 using NCIA(National Computerization Integrated Agency) cases. For the purpose, we analyze former researches related with civil service. And then, we propose web2.0 adaptation strategies for NCIA.

• Journal of Korean Institute of Industrial Engineers
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• v.38 no.2
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• pp.98-106
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• 2012

The current market preassure of least environmental effects of products needs companies to consider whole life cycle of their products during their design phase. To support the integrated and collaborative development of the products, this paper proposed product data model for extended Product Data Managemen (PDM) that can support integrated design of product, manufacturing process, and customer services, based on the consistent and comprehensive PDM databases. The product data model enables design, manufacturing, and service engineers to express their products and services efficiently, with sharing consistent product data, engineering changes, and both economical and environmental evaluations on their design alternatives. The product data model was implemented with a prototype PDM system, and validated through an example product. The result shows that the PDM based on the proposed product data model can support the integrated design for products, manufacturing process, and customer services, and provide an environment of collaborative product development for design, manufacturing and service engineers.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.12
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• pp.2392-2396
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• 2011

This paper deals with the power integration of large urban railway systems to improve regenerative energy utilization. Current regenerative energy utilization is low because there is no special plan for using this energy. If the railway system is integrated with other railway systems, the efficiency is expected to be improved. Through the case studies, to find the realistic effect of integrated operation, real system for the Seoul Metro lines, especially line 5 and 7, had been applied.

• Journal of Power Electronics
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• v.14 no.1
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• pp.143-155
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• 2014

The stability issues of a multi-module distributed DC power system without current-sharing loop are analyzed in this study. The physical understanding of the terminal characteristics of each sub-module is focused on. All the modules are divided into two groups based on the different terminal property types, namely, impedance (Z) and admittance (Y) types. The equivalent circuits of each group are established to analyze the stability issues, and the mathematical equations of the equivalent circuits are derived. A generalized criterion for multi-module distributed systems is proposed based on the stability criterion in a cascade system. The proposed criterion is independent of the power flow direction.

• Progress in Superconductivity and Cryogenics
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• v.3 no.1
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• pp.11-15
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• 2001

Stability of a Bi-2223/Ag tape was studied by using a numerical model considering the temperature distribution of cross-sectional area. The dynamic evolution of normal zone of a HTS tape can be shown by the developed two-dimensional Program using finite difference method. Two kinds of analyses are compared to quantify the critical disturbance energy for quenching HTS tapes. One is the length-thickness(x-r) side and the other is the length-width(x-z) side. For each case. the governing energy balance equations and corresponding boundary conditions are formulated. The results of analyses shows that the critical disturbance energies for each cases seem to be very close for considered Bi-2223/Ag tape .