• Advances in nano research
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• v.6 no.2
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• pp.163-182
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• 2018

Based on the Reissner mixed variational theorem (RMVT), the authors present a nonlocal Timoshenko beam theory (TBT) for the nonlinear free vibration analysis of multi-walled carbon nanotubes (MWCNT) embedded in an elastic medium. In this formulation, four different edge conditions of the embedded MWCNT are considered, two different models with regard to the van der Waals interaction between each pair of walls constituting the MWCNT are considered, and the interaction between the MWCNT and its surrounding medium is simulated using the Pasternak-type foundation. The motion equations of an individual wall and the associated boundary conditions are derived using Hamilton's principle, in which the von $K{\acute{a}}rm{\acute{a}}n$ geometrical nonlinearity is considered. Eringen's nonlocal elasticity theory is used to account for the effects of the small length scale. Variations of the lowest frequency parameters with the maximum modal deflection of the embedded MWCNT are obtained using the differential quadrature method in conjunction with a direct iterative approach.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.75-80
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• 2005

As a result of globalization process and TBT agreement, KS is also being revised, reestablished and some are abolished according to international standards such as ISO, IEC, etc. Conventional KS sampling inspection standards contained many different procedures from ISO, but recently, to match with international standards, all the rest of the standards except KS A 3102, 3104, 3151 were abolished, and the even the ones being in use still are also scheduled and be revised. Especially, KS A 3101, KS A 3105, KS A 3109, which were used most frequently in Korea were abolished, and the KS A ISO $2859-0\~3$ which coincide with ISO standards were established 3 years ago, but the implementation rate is very slow. Starting next year the national examination for qualification process for the product quality related item will the started and the preparation is underway. This study will investigate the recent sampling inspection process of KS as well as SPC related KS overhaul problem and present the data to help workers in SPC related field. One of the main example will be on KS A ISO 2859-3 and will attempt to help those medium and small sized companies with examples.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.9
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• pp.59-64
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• 2015

IEC is an international standards which are used in many countries with Europe as the center. IEC standard is introduced in Korea according to WTO/TBT agreements, however until now there are no buildings in Korea which are designed applying IEC standard. Therefore, KEA(Korea Electric Association) is scheduled to construct Korean low voltage electrical installation integration test site which is designed applying IEC standard. In this paper, before being under construction of Korean low voltage electrical installation integration test site, power substation is modeled based on real design parameters and method to select circuit breakers and cables is presented applying IEC standard in the modeled power substation. EMTP(ElctroMagnetic Transient Program) is used for simulation program. EMTP which is power system analysis program is easy to model power system and power substation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.2
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• pp.159-165
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• 1999

Experimental studies have been performed to observe the basic phenomena of waste bed combustion in MSW incinerator. A reduced scale apparatus was utilized to simulate the combustion behavior in real plant with 1-dimensional transient behavior at the experimental setup, which uses wet cubic wood with ash content as simulated waste. LHV (lower heating value) of solid fuel, fuel particle size and flow rate of combustion air were taken as important parameters of the bed combustion. For the quantitative analysis, FPR (flame propagation rate), TBT (total burn-out time) and PBT (particle burn-out time) was defined. LHV represent the capability of heat release of the fuel, so that a higher LHV results in faster reaction rate of the fuel bed, which is shown by higher FPR. Fuel particle size is related with surface area per unit mass as well as heat and mass transfer coefficient. As the particle size increases the FPR decreases owing to decreasing specific surface area. Air injection supplies oxygen to the reaction zone. However oversupply of combustion air increases convection cooling of the bed and possibly extinguishes the flame.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1631-1632
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• 2015

기술의 발전과 사회/환경변화, WTO/TBT 및 FTA 협정 이행을 위한 국제표준 도입 등 대내 외적 환경에 능동적/선제적으로 대처하기 위하여 국제표준 수준의 규정인 한국전기규정(KEC) 제정(안)을 개발하고 있다. 한국전기규정(KEC)은 국제표준인 IEC를 근간으로 하고, 상세사항은 DIN, BS, NEC 등의 선진표준을 참조, 국내외 표준들의 비교/조사를 통한 개발을 목적으로 제정 중에 있다. 한국전기규정(KEC)은 제1편 공통분야와 제2편 저압전기설비분야, 제3편 고압전기설비분야, 제4편 지능형전력망분야 등 총 4편으로 구성되며 이 중 피뢰시스템은 IEC 62305를 기초로 하여 제정되었다. 본 논문에서 한국전기규정(KEC) 제1편 제5부 피뢰시스템분야에 대한 중요사항에 대해 제시하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1633-1634
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• 2015

WTO/TBT 협정에 따라 2006년부터 IEC 전선의 전면적인 사용과 전기설비기술기준의 판단기준에 IEC 60364 저압전기설비분야의 도입으로 국내현장에서 국제표준을 적용할 수 있게 되었다. 그러나 국제표준(IEC)은 내용이 포괄적이며, 원론적인 부분을 다루고 있어 실제 현장 적용에 많은 어려움이 있다. 이에 따라 대한전기협회에서는 국제표준(IEC)을 기초로 하여 국제수준과 대등한 "한국전기규정 KEC"를 제정중이며, 본 연구는 KS C IEC 60364-5-52 기초로 작성한 KEC 제2편 저압전기설비분야 제43장 배선설비의 제정현황을 소개하는 것이다.

• International Commerce and Information Review
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• v.10 no.4
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• pp.439-455
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• 2008

The SPS Agreement, concluded in the Uruguay Round for the purpose of controlling SPS risks, has traditionally been recognized to maintain the narrowest scope of application compared with TBT Agreement and GATT in relation with environmental provisions. Contrary to such an understanding on the scope of the SPS Agreement, the panel in the EC-Biotech case found that the SPS Agreement extends to regulate trade-restrictive measures on Genetically Modified Organizations(GMOs) causing health and environmental risks. This expanding scope of the SPS Agreement would have substantial influence on domestic environmental regulations as well as Multilateral Environmental Agreements(MEAs). This paper discusses the consequences of an expanding ambit for the WTO SPS Agreement through the designation of a wider range of health and environmental regulations affecting trade as SPS measures. As a result, not only precautionary measures on GMO risks, but also other health and environmental measures with trade impacts, could be subject to SPS control, and consequently, the institutional rigors of the WTO regime. However, strict and literal interpretation of the SPS provisions to expand its applicable scope would cause concerns about the WTO's intervention on the purely environmental measures. Pursuing harmonized and flexible interpretation of provisions on environment-related conflicts as well as accepting precautionary principle included MEAs will contribute to reduce such kind of concerns.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3362-3366
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• 2013

A simple and quick separation technique for selenite in natural water was developed using $TiO_2$@$SiO_2/Fe_3O_4$ nanoparticles. For the synthesis of nanoparticles, a polymer-assisted sol-gel method using hydroxypropyl cellulose (HPC) was developed to control particle dispersion in the synthetic procedure. In addition, titanium butoxide (TBT) precursor, instead of the typical titanium tetra isopropoxide, was used for the formation of the $TiO_2$ shell. The synthesized nanoparticles were used to separate selenite ($Se^{4+}$) in the presence of $Se^{6+}$ or selenium anions for the photocatalytic reduction to $Se^0$ atom on the $TiO_2$ shell, followed by magnetic separation using $Fe_3O_4$ nanoparticles. The reduction efficiency of the photocatalytic reaction was 81.4% at a UV power of 6W for 3 h with a dark adsorption of 17.5% to the nanoparticles, as determined by inductively coupled plasma-mass spectrometry (ICP-MS). The developed separation method can be used for the speciation and preconcentration of selenium cations in environmental and biological analysis.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.6
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• pp.59-72
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• 2002

Along with the enlargement of WTO, issues about standardization activity are more and more become concerning object worldwide. Countries launch the work that putting the standardization in order, such as re-establishing their standardization strategy. With the chance of entering WTO, China is promoting the rebuilding of standardization system in order to conform to international standardization system. Thus, in this paper, research make it clear that the variation of circumstance of standardization activity, the importance of the standardization activity, and the international movement, in the meantime, it surveyed the development course of standardization activity and it's present operating system. By this means, it concludes the problems of present operating system and implies the improving scheme. Further more, this paper implies Chinese characteristic standardization system which conform with WTO/TBT and international standardization system. Firstly, through the comprehensive analysis on standardization system, it figures out the main function of relevant organizations in each working stage. Secondly, this paper makes a system model composed of possible three stage, and setup items needs promotion and main target in each stage. Finally, this paper point out the development direction of standardization system, it also implies it's limitation and the later possible research topic in this field.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.5
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• pp.37-45
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• 2007

WTO/TBT requires that, for technical regulations affecting trade, technical regulatory requirements must be specified where possible in terms of performance rather than design or descriptive characteristics. The movement which made "performance" a keyword in landscape architecture was activated in Japan, one of the leading counties in performance-based regulatory system(PBRS). The Japanese recent movement of systematization activity on performance-based standards and specifications was reviewed and operational applications for performance-based regulatory system in South Korea are summarized as follows: 1. The establishment of performance standards that can be properly evaluated by assessment indicators is necessary in cases when quantitative evaluation is difficult. 2. As a preparation for PBRS, a brief procurement system by technical proposal for the landscape design and construction is necessary. 3. As a preparation for PBRS, activation of an environmental performance evaluation on experimental construction is necessary. 4. As a preparation for PBRS, a certification system of environmental performance on various landscape construction methods is necessary. 5. The Private Finance Initiative Project is the most similar to PBRS therefore, activation of the Private Finance Initiative Project is necessary in landscape architecture projects for park rehabilitation.