• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.11
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• pp.790-800
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• 2013

The optimal structure of 1-3 piezocomposites has been determined by controlling polymer properties, ceramic volume fraction, thickness of composite and aspect ratio of the composite to maximize the TVR (transmitting voltage response), RVS (receiving voltage sensitivity) and FBW (fractional bandwidth) of underwater acoustic transducers. Influence of the design variables on the transducer performance was analyzed with equivalent circuits and the finite element method. When the piezocomposite is vibrating in a pure thickness mode, inter-pillar resonant modes are likely to occur between lattice-structured piezoceramic pillars and polymer matrix, which significantly deteriorate the performance of the piezocomposite. In this work, a new method to design the structure of the 1~3 type piezocomposite was proposed to maximize the TVR, RVS and FBW while preventing the occurrence of the inter-pillar modes. Genetic algorithm was used in the optimal design.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.2
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• pp.5-26
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• 2015

The aims of this study are to review the changes and trends of information literacy standards in higher education in the U.S. and the U.K.; to examine British SCONUL's two information literacy standards which were announced in 1999 and in 2011 respectively; and to compare and analyze the two information literacy standards (i.e., Core Model and Research Lens) which were released by SCONUL in 2011. By employing the research methods of literature review and content analysis, this study tries to find the implications that may be used as a basic data when the country's relevant institutions plan to consider the information literacy standards in higher education in the near future.

• Geotechnical Engineering
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• v.8 no.3
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• pp.75-88
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• 1992

In this study the foundation methods which our ancestors, through a historical age as early as three kingdom's period, adopted for their civil structures and buildings have been reviewed by investigating the discovered relics. It is shown that they already, from about 2000 years ago, had applied various foundation techniques considering the structure types and the foundation soil conditions. The ancient foundation methods are categorized as artificially laid alternating soil and boulder layers under heavy structures, compacted soil base under wide loaded area, stone column under pillars of buildings, stacked long stone footing for special buildings such as palace buildings, and piling for bridges, They are analyzed with respect to current foundation techniques.

• Advances in concrete construction
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• v.4 no.4
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• pp.319-332
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• 2016

In most cases strengthening reinforced concrete columns exposed to high strain rate is to be expected especially within weak designed structures. A special type of loading is instantaneous loading. Rapid loading can be observed in structural columns exposed to axial loads (e.g., caused by the weight of the upper floors during a vertical earthquake and loads caused by damage and collapse of upper floors and pillars of bridges).Subsequently, this study examines the behavior of reinforced concrete columns under rapid loading so as to understand patterns of failure mechanism, failure capacity and strain rate using finite element code. And examines the behavior of reinforced concrete columns at different support conditions and various loading rate, where the concrete columns were reinforced using various counts of FRP (Fiber Reinforcement Polymer) layers with different lengths. The results were compared against other experimental outcomes and the CEB-FIP formula code for considering the dynamic strength increasing factor for concrete materials. This study reveals that the finite element behavior and failure mode, where the results show that the bearing capacity increased with increasing the loading rate. CFRP layers increased the bearing capacity by 20% and also increased the strain capacity by 50% through confining the concrete.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.1
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• pp.17-24
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• 2010

This paper aims to clarify the spatial form and functional characteries of traditional market place in Seomjin river. The objects of this study are Gokseong, Gurye, Soonchang, and Okgok market place. The results are as follows. First, the form of the traditional market that it was open focusing on large open space of a village was maintained until now. Second, the spatial form of a market place surrounds market-shop located at the center of a market, and a permanent market-store is located in a line. Spatial element important for constituting a market place is three, market-shop, stall, and the mall of market place, and each spatial element is functioning in linkage. The unit space of market-shop is mainly determined by between pillars, and a store is opened. And the same type of industry adjoins, and market-shop's forms a fixed domain and is distributed. The stall is located with many kinds and forms at street mall, and it is taking charge of the important function of trade.

• Korean Journal of Materials Research
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• v.27 no.12
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• pp.679-687
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• 2017

A strain-gradient crystal plasticity finite element method(SGCP-FEM) was utilized to simulate the compressive deformation behaviors of single-slip, (111)[$10{\bar{1}}$], oriented FCC single-crystal micro-pillars with two different slip-plane inclination angles, $36.3^{\circ}$ and $48.7^{\circ}$, and the simulation results were compared with those from conventional crystal plasticity finite element method(CP-FEM) simulations. For the low slip-plane inclination angle, a macroscopic diagonal shear band formed along the primary slip direction in both the CP- and SGCP-FEM simulations. However, this shear deformation was limited in the SGCP-FEM, mainly due to the increased slip resistance caused by local strain gradients, which also resulted in strain hardening in the simulated flow curves. The development of a secondly active slip system was altered in the SGCP-FEM, compared to the CP-FEM, for the low slip-plane inclination angle. The shear deformation controlled by the SGCP-FEM reduced the overall crystal rotation of the micro-pillar and limited the evolution of the primary slip system, even at 10 % compression.

• Journal of Genetic Medicine
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• v.17 no.1
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• pp.1-10
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• 2020

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women, which is characterized by the oligo/anovulation, hyperandrogenism (HA) and polycystic ovarian morphology which are diagnostic criteria. PCOS has diverse clinical aspects in addition to those diagnostic criteria including increased risk for cardiovascular diseases, metabolic syndrome, dyslipidemia, type 2 diabetes and impaired fertility. Because of the heterogeneity of the disease, the pathogenesis of the disease has not been elucidated yet. Therefore, there is no cure for the endocrinopathy. HA and insulin resistance (IR) has been considered two major pillars of the pathogenesis of PCOS. Recent advances in animal studies revealed the critical role of neuroendocrine abnormalities in developing PCOS. Several pathways related to neuroendocrine origin have been investigated such as hypothalamus pituitary ovarian axis, hypothalamus pituitary adrenal axis and hypothalamus pituitary adipose axis. This review summarizes the current knowledge about the role of HA and IR in developing PCOS. In addition, we review the results of recent genome wide association studies for PCOS. This new perspective improves our understanding of the role of neuroendocrine origins in PCOS and suggest a novel potential therapeutic target for the treatment of PCOS.

• Journal of KSNVE
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• v.4 no.4
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• pp.479-486
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• 1994

The Finite Element Method(FEM) generally used for the structural analysis has some defects, i.e. a great deal of computational time and huge memory capacity of computer are needed in the application to large and/or complex structures, etc. Therefore the Component Mode Synthesis method(CMS), one of sub-structure synthesis methods, was made to improve such demerits and has been developed up to now. In optimum structural modification problems, the sensitivity analysis method is useful, where the sensitivity-calculated by Fox's suggestion-is defined as the diffentials of design variables for the objective values. This paper discusses the vibration minimization techniques for the oper box type structure, in which it is assumed that an engine operates at 10-40Hz range. The results obtained are as follow; (1) The sensitivity of natural frequency could be easily obtained by sensitivity analysis method and the optimum position to insert pillars could be found by using it. (2) The rates of structural modification could be exactly obtained and the natural frequency observed could be easily shifted to the objective value. (3) The maximum amplitude around natural frequency noted could be nearly reduced to 1/25 by modification.

• Journal of Information Management
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• v.39 no.1
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• pp.1-25
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• 2008

As scholarly information environment rapidly changes, library consortia for electronic journal licensing come to require strategies to better address service needs of member institutions as well as to take parts in more progressive initiatives. This study aims to develop a more future-oriented and progressive business model for electronic journal licensing consortia. The model is based on three pillars: strategies for responding to immediate needs; long-term strategies for leading change; and organizational infrastructure.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.5
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• pp.583-589
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• 2019

One of the core pillars of the Fourth Industrial Revolution is the innovation of the manufacturing industry. From the beginning, the 4th Industrial Revolution appeared in Germany under the concept of 'Industrial 4.0', which means a radical change in the manufacturing industry that can provide super intelligent product production and services based on artificial intelligence and big data. Since manufacturing innovation is a change in the industrial character of the entire nation, the initial role of government is important. Korea also has various policies related to the 4th Industrial Revolution, but there are still various problems to be solved. Therefore, this paper monitors and analyzes the public R&D projects of the advanced countries on manufacturing innovations in the background mentioned above, and through this, the policy implications are drawn.