• Structural Monitoring and Maintenance
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• 제5권2호
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• pp.189-204
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• 2018

This paper examines the seismic responses of a reinforced concrete (RC) frame core-tube building with pre-pressed spring self-centering energy dissipation (PS-SCED) braces. The PS-SCED brace system consists of friction devices for energy dissipation, pre-pressed combination disc springs for self-centering and tube members as guiding elements. A constitutive model of self-centering flag-shaped hysteresis for PS-SCED brace is developed to better simulate the seismic responses of the RC frame core-tube building with PS-SCED braces, which is also verified by the tests of two braces under low cyclic reversed loading. Results indicate that the self-centering and energy dissipation capabilities are well predicted by the proposed constitutive model of the PS-SCED brace. The structure with PS-SCED braces presents similar peak story drift ratio, smaller peak acceleration, smaller base shear force and much smaller residual deformations as compared to the RC frame core-tube building with bucking-restrained braces (BRBs).

• Advanced Composite Materials
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• 제16권1호
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• pp.11-30
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• 2007

Since delamination often propagates at the interfacial layer between a surface skin and a foam core, a crack arrester is proposed for the suppression of the delamination. The arrester has a semi-cylindrical shape and is arranged in the foam core and is attached to the surface skin. Here, energy release rates and complex stress intensity factors are calculated using finite element analysis. Effects of the arrester size and its elastic moduli on the crack suppressing capability are investigated. Considerable reductions of the energy release rates at the crack tip are achieved as the crack tip approached the leading edge of the crack arrester. Thus, this new concept of a crack arrester may become a promising device to suppress crack initiation and propagation of the foam core sandwich panels.

• Asia pacific journal of information systems
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• 제11권3호
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• pp.23-42
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• 2001

Recently, knowledge management becomes a core management tool for efficient and effective organizations. However, there are little known researches on measuring knowledge management level. The objective of this paper is to develop a process capability model for knowledge management of an organization. We developed 5 stage process capability model for knowledge management. The 1st stage is the initial stage where no significant knowledge management activity is performed. The 2nd stage is the performed stage where planning and tracking activities are performed on organization level. The 3rd stage is the established, and the 4th stage is the predictable stage where processes and results of knowledge management can be predictable. Final stage is the optimizing stage where knowledge management process is continuously improved at an organizational level. We surveyed 37 korean companies to test the validity of the proposed stage model. Statistical tests show that the developed stage model of knowledge management is valid and sound in general conditions. The result of this study on process capability model can be a solid stepping stone for future works in this area.

• 한국엔터테인먼트산업학회논문지
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• 제13권4호
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• pp.195-206
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• 2019

이 연구는 국내 스포츠계열 대학생들이 인식하는 핵심역량에 대한 중요도와 실행도를 분석하여 향후 미래사회가 요구하는 방향으로 스포츠계열 학생들의 역량을 강화시킬 수 있는 방향과 방법을 도출하는데 그 목적이 있다. 309명의 스포츠계열 전공 대학생들을 대상으로 분석한 결과는 다음과 같다. 첫째, 스포츠계열 대학생들이 인식하는 핵심역량의 중요도에서는 자기관리역량, 대인관계역량, 의사 소통능력, 종합적 사고력, 자원정보 기술 활용역량, 글로벌 역량의 순으로 나타났다. 둘째, 스포츠계열 대학생들이 평가하는 자신들의 핵심역량 보유 실행도는 대인관계역량, 자기관리역량, 의사소통능력, 종합적 사고력, 글로벌 역량, 자원정보 기술 활용역량의 순으로 나타났다. 셋째, 핵심역량의 중요도와 실행도의 차이는 모든 영역에서 유의한 차이가 있는 것으로 나타났고, 차이가 큰 영역은 종합적 사고력, 의사소통능력, 자원정보 기술 활용역량, 자기관리역량, 글로벌 역량, 대인관계역량의 순으로 나타났다. 스포츠계열 대학생들은 대인관계역량과 자기관리역량, 의사소통능력은 상대적으로 높이 평가한 반면 종합적 사고력, 자원정보 기술 활용역량, 글로벌 역량은 취약한 것으로 나타나, 이를 보완할 수 있는 교육과정의 변화를 통해 미래 사회가 요구하는 인재로 거듭날 수 있을 것이다. 따라서 대학은 교육과정의 혁신과 교수자의 역량 강화를 통해 경쟁력 있는 스포츠계열 인재를 양성하는 것이 필요하며, 이것이 곧 대학의 경쟁력 제고와 연결될 수 있음을 인식해야 한다.

• 산업공학
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• 제25권1호
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• pp.52-63
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• 2012

Up-to-date enlargement of the scale of global outsourcing has brought about the need of systematic and efficient tools for competitive supplier discovery located in various areas. A web-based business supporting system, referred to as Excellent Manufacturer Scouting System(EMSS), is being developed to serve core business functions including supplier discovery, negotiation, and collaboration between overseas buyers and domestic suppliers throughout the process of supply chain formation. In this paper, a supplier assessment model devoted to evaluation of core manufacturing capability is proposed by targeting small and medium sized mold companies. The assessment model will eventually be loaded to EMSS. Even if many well-designed models for supplier assessment have been presented in literature, most of them limit the evaluation criteria to somewhat general information on a given supplier, such as cost, delivery time, quality, rather than core manufacturing capability itself. This research is pioneering work on supplier assessment from the viewpoint of manufacturability. The proposed assessment model classifies assessment indices into six criteria, which have been drawn by intensive survey and analysis of the mold industry. Actual assessment indices for each criterion are also presented along with an exemplary evaluation result.

• Nuclear Engineering and Technology
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• 제32권4호
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• pp.395-409
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• 2000

Parametric studies were performed to assess the sensitivity in determining the maximum in-vessel heat removal capability from the core material relocated into the lower plenum of the reactor pressure vessel (RPV）during a core melt accident. A fraction of the sensible heat can be removed during the molten jet delivery from the core to the lower plenum, while the remaining sensible heat and the decay heat can be transported by rather complex mechanisms of the counter-current flow limitation (CCFL) and the critical heat flux (CHF）through the irregular, hemispherical gap that may be formed between the freezing oxidic debris and the overheated metallic RPV wall. It is shown that under the pressurized condition of 10MPa with the sensible heat loss being 50% for the reactors considered in this study, i.e. TMI-2, KORI-2 like, YGN-3&4 like and KNGR like reactors, the heat removal through the gap cooling mechanism was capable of ensuring the RPV integrity as much as 30% to 40% of the total core mass was relocated to the lower plenum. The sensitivity analysis indicated that the cooling rate of debris coupled with the sensible heat loss was a significant factor The newly proposed heat removal capability map (HRCM) clearly displays the critical factors in estimating the maximum heat removal from the debris in the lower plenum. This map can be used as a first-principle engineering tool to assess the RPV thermal integrity during a core melt accident. The predictive model also provided ith a reasonable explanation for the non-failure of the test vessel in the LAVA experiments performed at the Korea Atomic Energy Research Institute (KAERI), which apparently indicated a cooling effect of water ingression through the debris-to-vessel gap and the intra-debris pores and crevices.

• Structural Engineering and Mechanics
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• 제65권6호
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• pp.657-678
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• 2018

Sandwich structures are well known for their use in aircraft, naval and automobile industries due to their high strength resistance with light weight and high energy absorption capability. Sandwich beams with soft core are very common and simple structures that are employed in day to day general use appliances. Modeling and analysis of sandwich structures is not straight forward due to the interactions between core and face sheets. In this paper, formulation of Super Convergent finite elements for analysis of the sandwich beams with soft core based on Euler Bernoulli beam theory are presented. Two elements, Eul4d with 4 degrees of freedom assuming rigid core in transverse direction and Eul10d with 10 degrees of freedom assuming the flexible core were developed are presented. The formulation considers the top, bottom face sheets and core as separate entities and are coupled by beam kinematics. The performance of these elements are validated by results available in the published literature. Number of studies are performed using the formulated elements in static, free vibration and wave propagation analysis involving various boundary and loading conditions. The paper highlights the advantages of the elements developed over the traditional elements for modeling of sandwich beams and, in particular wave propagation analysis.

• Nuclear Engineering and Technology
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• 제31권4호
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• pp.391-400
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• 1999

A conceptual core design of the 1,300MWe KNGR (Korean Next Generation Reactor) without using soluble boron for reactivity control was developed to determine whether it is technically feasible to implement SBF (Soluble Boron Free) operation. Based on the borated KNGR core design, the fuel assembly and control rod configuration were modified for extensive use of burnable poison rods and control rods. A new fuel rod, in which Pu-238 had been substituted for a small amount of U-238 in fuel composition, was introduced to assist the reactivity control by burnable poison rods. Since Pu-238 has a considerably large thermal neutron capture cross section, the new fuel assembly showed good reactivity suppression capability throughout the entire cycle turnup, especially at BOC (Beginning of Cycle). Moreover, relatively uniform control of power distribution was possible since the new fuel assemblies were loaded throughout the core. In this study, core excess reactivity was limited to 2.0 %$\delta$$\rho$ for the minimal use of control rods. The analysis results of the SBF KNGR core showed that axial power distribution control can be achieved by using the simplest zoning scheme of the fuel assembly Furthermore, the sufficient shutdown margin and the stability against axial xenon oscillations were secured in this SBF core. It is, therefore, concluded that a SBF operation is technically feasible for a large sized LWR (Light Water Reactor).

• 전자공학회논문지D
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• 제34D권11호
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• pp.54-63
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• 1997

The 1-D finite-element mehtod is applied for designing double-clad otpical fibers with dispersion-compensation capability. design parameters allowing only a $LP_{01}$ single mode are treated and macro-bending loss are taken into consideration. Design parameters are extracted to have the compensation ratio $(L_{SMF}/L_{DCF})$ of 6.2 for core structure with step-index profile, and of 5.2 for core with triangular-index profile.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1103-1106
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• 1999

Telegram is an indispensible information & telecommunication system to our daily life. VTS(Voice Telegram System) under intensive research is intended to enhance exchanging capability of information & telecommunication by adding voice media to existing telegram system. Overall configuration and necessary core technologies of the system were investigated for its development. Among those many technologies in need, the technology of compressing and recording data is most critical to the development of cheap hardware. This is so called vocoder algorithm and is the core technology of voice information system. So, here, vocoder algorithm now being studied will be introduced.