• Journal of electromagnetic engineering and science
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• v.2 no.2
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• pp.68-74
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• 2002

In this paper, a pre-layout design approach for high-speed microprocessor is proposed. For multilayer PCB stark up configuration as well as selection and placement of decoupling capacitors, an effective solution for reducing SSN and EMI is obtained by modeling and simulation of complete power distribution system. The system model includes VRM, decoupling capacitors, multiple power and ground planes for core voltage, vias, as well as microprocessor. Finally, the simulation results are verified by measurements data.

• 에너지협의회보
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• s.76
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• pp.61-64
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• 2006

Ladies and gentlemen, dear friends and colleagues, it is an honour and a pleasure for me to introduce this event dedicated to the world energy outlook. For a Group like EDF, decisions taken today will have a very long range impact, well into the century (2060-2100). Thinking about the future is therefore a truly useful exercise in the decision-making process. We are at a crossroads. It has been somewhat perplexing to see how widely future scenarios have tended to diverge. So, which path should be taken if all seem equally viable? Thankfully, it seems to me that we are in fact moving towards greater convergence on core issues. I ’m going to attempt to draw out the main points as to why this may be the case. I will first discuss the various scenarios, then the time, technological and political dimensions of the energy outlook.

• Nuclear Engineering and Technology
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• v.31 no.1
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• pp.80-87
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• 1999

An analytic axial xenon oscillation model was developed for pressurized water reactor analysis. The model employs an equation system for axial difference parameters that was derived from the two-group one-dimensional diffusion equation with control rod modeling and coupled with xenon and iodine balance equations. The spatial distributions of nu, xenon, and iodine were expanded by the Fourier sine series, resulting in cancellation of the flux-xenon coupled non-linearity. An inhomogeneous differential equation system for the axial difference parameters, which gives the relationship between power, iodine and xenon axial differences in the case of control rod movement, was derived and solved analytically. The analytic solution of the axial difference parameters can directly provide with the variation of axial power difference during xenon oscillation. The accuracy of the model is verified by benchmark calculations with one-dimensional reference core calculations.

• Journal of the Optical Society of Korea
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• v.10 no.4
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• pp.174-177
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• 2006

We propose a new technique to minimize gain-transient time of wavelength-division-multiplexing (WDM) signals in erbium-doped fiber amplifiers (EDFA) in channel add/drop networks. We have dramatically reduced the gain-transient time to less than $3{\mu}sec$ by applying, for the first time to our knowledge, a disturbance observer with a proportional/integral/differential (PID) controller to the control of EDFA gain. The $3{\mu}sec$ gain-transient time is the fastest one ever reported and it is approximately less than 1.5% of $200{\mu}sec$ gain-transient time of commercially available EDFAs for WDM networks. We have demonstrated the superiority of the new technique by performing the simulation with a numerical modeling software package such as the $Optsim^{TM}$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.1-10
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• 2008

In the knowledge-based society which recognizes knowledge as a core value, knowledge management is one of the most interesting issues. The creation of knowledge within an organization occurs as a result of interactions of tacit and explicit knowledge, in process of knowledge conversion. One useful model of this process is the SECI model which stands for a process of socialization, externalization, combination and internalization of knowledge. The enterprise competitive power depends on how an organization accelerates the speed of the cycle of knowledge creation well. In this paper we introduce a knowledge management promotion system based on SECI model and proposal system to promote the cycle of knowledge creation in production fields, and study an enterprise case.

• 한국디지털정책학회:학술대회논문집
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• 2005.11a
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• pp.383-389
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• 2005

The purpose of this paper is to develop the metadata on the information of research result in Science and technology and to design the domain knowledge structure using semantic web technology for further implementation. In this paper, we first analyze the existing theories and techniques related to the metadata in such fields as R&D research result, international standard, and semantic web. Then, we extract and group the relevant factors from Dublin Core, CERIF, and the research results for building the integrated metadata framework. Based on our proposed metadata, we design a domain knowledge structure which employs RDF/RDFS as knowledge representation tool. Therefore, we can implement the ontology which produce the 'intelligent' information service and improve the interoperability between the research institutions. Also, the metadata can be used as the basis for developing National R&D Performance Information, and in terms of research institutions, can be used as tools for managing the their own research results information systematically and consistently.

• Journal of Magnetics
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• v.2 no.4
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• pp.130-134
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• 1997

The amorphous Co-based alloy Co66Fe4Ni1B15Si14 (Metglas 2714A) is a suitable magnetic core material for high frequency operation. Appreciable reduction of the coercive force can be achieved by proper heat treatment. In this study, samples annealed at wide temperature range were analyzed using differential scanning calorimetry, high frequency B-H loop tester, X-ray diffractometer and resistivity meter. The results show that coercive force at 10 kHz decreases with in-creasing annealing temperature up to 773 K, but dramatically increases above this temperature. The squareness shows that the magnetic anisotropy on longitudinal direction of the as-cast state remains up to 773 K. Above this temperature, it decreases down to 0.5 that represents random distribution of magnetic domains. The crystallization abruptly occurs between 781 K and 783 K.

• Journal of Information Technology Services
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• v.2 no.2
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• pp.121-134
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• 2003

To improve the quality of the services and to concentrate on the core capability, in public sector the IT outsourcing is recently being vitalized by the institutional support of the government for the entrusting non-government. Because the lots of general studies so far have simply focused on indicating fragmentary factors i.e. economical factors, risk factors, system factors, or induction objects, etc., they are insufficient in making the practical decisions, therefore we indicated systemized model extending over the whole range of the IT outsourcing to support substantial decision makings, and assorted 4 categories and drew considerable 55 factors from the literature study to materialize the previously considerable factors at each decision making stage. And the principal factors were drawn from each decision making category by a group of 11 experts. Besides, a henceforth plan for the application was also presented through an actual example of the IT outsourcing decision making process of 'M', a public enterprise.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.195-207
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• 1999

Classification and Coding(C&C) systems as a core of design information management have been accomplished by many studies in terms of design and manufacturing attribute based on Group Technology. Those are very difficult to apply in make-to-order(MTO) manufacturing because the environment of MTO has various characteristics of product, many licensors, engineering change, insufficiency of integrated management system for codes and so on. This paper presents a suitable C&C system to MTO manufacturing which consider management level and drawing. The steps of developing the C&C system are as follows: 1) analysis of existing coding system and drawing type; 2) design of C&C system; 3) practice of designed coding system to a field.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2809-2812
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• 2010

The Chemical Doping of epitaxial graphene (EG) due to p-tert-butylcalix[4]arene was investigated using high resolution photoemission spectroscopy (HRPES). The measured work function changes verified that increased adsorption of the p-tert-butylcalix[4]arene on EG showed p-type doping characteristics due to charge transfer from the graphene to the p-tert-butylcalix[4]arene through the hydroxyl group. A single oxygen bonding feature associated with the O 1s peak was clearly observed in the core-level spectra, indicating the presence of one equivalent adsorption state.