• The Magazine of the IEIE
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• v.29 no.9
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• pp.48-67
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• 2002

Basic introduction to direct conversion architecture was given in comparison with heterodyne one. Principal difficulties in implementation of direct conversion receiver were presented, current state of research in this field and classified, on the basis of extensive analysis of published materials.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.9 no.4
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• pp.3-10
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• 1999

More concerns are concentrated in finite fields arithmetic as finite fields being applied for Elliptic curve cryptosystem coding theory and etc. Finite fields arithmetic is affected in represen -tation of those. Optimal normal basis is effective in hardware implementation and polynomial field which is effective in the basis conversion with optimal normal basis and show that the arithmetic of finite field with the basis is effective in software implementation.

• Korean Journal of Computational Design and Engineering
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• v.5 no.3
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• pp.276-284
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• 2000

Usual practice of the transformation of a B-spline curve into a set of piecewise polynomial curves in a power form is done by either a knot refinement followed by basis conversions or applying a Taylor expansion on the B-spline curve for each knot span. Presented in this paper is a new algorithm, called a direct expansion algorithm, for the problem. The algorithm first locates the coefficients of all the linear terms that make up the basis functions in a knot span, and then the algorithm directly obtains the power form representation of basis functions by expanding the summation of products of appropriate linear terms. Then, a polynomial segment of a knot span can be easily obtained by the summation of products of the basis functions within the knot span with corresponding control points. Repeating this operation for each knot span, all of the polynomials of the B-spline curve can be transformed into a power form. The algorithm has been applied to both static and dynamic curves. It turns out that the proposed algorithm outperforms the existing algorithms for the conversion for both types of curves. Especially, the proposed algorithm shows significantly fast performance for the dynamic curves.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.321-324
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• 2002

For a rule-based conversion of Hangout into the Roman alphabet rather than a word-for-word conversion, one must come up with a faultless model for the Korean standard pronunciation rules, which are the basis of the Romanization. It is on this foundation that the Korean-Roman alphabet conversion table can be created. For linguistic modeling using PetriNet, modeling boundary and notation of modeling can be defined. In order to describe PetriNet, which is a dynamic modeling tool, as a static one, one can model the standard Korean pronunciation rules and the Hangout-Roman alphabet notation by conversion into incident matrix Thus, this research attempts to develop a mathematical modeling tool for a natural language using PetriNet, and create a Korean-Roman alphabet conversion table.

• Ocean and Polar Research
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• v.23 no.2
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• pp.121-130
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• 2001

Geodetic datums define the size and shape of the earth and the origin and orientation of the coordinate systems used to map the earth. A lot of different datums have been developed and each nation uses its own datum as the basis for coordinate systems used to identify positions in geographic information systems. Recently GPS receivers are widely used to find out location and GPS is based on the World Geodetic System 1984(WGS-84) datum. Therefore the diversity of datums in use today requires accurate conversion between coordinates in different datums. In this study a coordinate conversion program on Windows is developed to transform between Tokyo Bessel(1941), which is the reference datum in Korea, and WGS-84. Several examples of coordinate conversion are presented and computed results are tested and proved to be correct.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.6 no.2
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• pp.75-84
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• 2002

Using good properties of an optimal normal basis of type I in a finite field ${\mathbb{F}}_{2^m}$, we present a design of a bit serial multiplier of Berlekamp type, which is very effective in computing $xy^2$. It is shown that our multiplier does not need a basis conversion process and a squaring operation is a simple permutation in our basis. Therefore our multiplier provides a fast and an efficient hardware architecture for a bit serial multiplication of two elements in ${\mathbb{F}}_{2^m}$.

• Management & Information Systems Review
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• v.7
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• pp.401-426
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• 2001

The form of company divides private and coporate companies. In general. private company has direct connection with owner's fortunes. On the contrary, cooperate company is established by a group of people who invest capital funds on their company and has an independent character. In the case of private company, their are many merits that owner can obtain all the benefits without divisions. However, the owner can mix up the control of accounting between public and private matters. As a result confusing, it is difficult to estimate financial situation of company and is limited to fund supply. Futhermore, owner has unlimited liabilities with law credit as a social cognition. Especially, the government tries to induce conversion of private company into cooperation one on the basis of benefits of tax and so on. In those situations, the purpose of this thesis is to study the management benefits with the conversion of private company into cooperate one focucing on the related tax reduction effect. To do this, I have reviewed all of the related textual achievements and tested the real significancy of tax reduction effect of conversion empirically. Finally, I have concluded that the conversion of private company into coporate one has many benefits including significant tax reduction effect. In other side, I have considered and reviewed many difficulties related conversion privated company into cooperate one and suggested some improvements as results. This thesis is comprises 5 chapters as follows; The first chapter explains purposes and methodologies and extents of this study. The second chapter deals the theoretical basis of conversion of private company into cooperate one and cooperates diverse benefits and types and processes of conversion. The preceding research achievements are also reviewed in this chapter. The third chapter deals empirical testing on the real tax reduction effect of the conversion. The analysis is proceeded through t-test of difference of tax between pre and after conversion. The result is presented so positively that I can conclude that cooperate conversion of private company has real benefit of tax reduction. The forth chapter deals the difficulties and improvements related with conversion. They are considered and reviewed at various aspects such as practical, financial and tax aspect. In fifth chapter, I summarise all of the significant points of this study and have conclusions in various aspects at last. In final point, this study is not enough in sample numbers and sample collecting area for empirical testing of significant tax reduction effect of cooperate conversion and research of more foreign achievements. Those are remained as continuing future studies.

• Journal of Advanced Navigation Technology
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• v.14 no.5
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• pp.655-660
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• 2010

This paper examines RF-to-DC conversion efficiency of rectifying circuit for wireless power transmission. The rectifying circuit consists of low pass filter, diode circuits and dc pass filter. All these components may be effect on the conversion efficiency. Using the simulation, we study these components how to effect on the conversion efficiency. On the basis of the simulation results, the 912MHz rectifying circuit with 50% efficiency at low input power such as 0dBm is fabricated and its characteristics are measured.

• Journal of electromagnetic engineering and science
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• v.8 no.2
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• pp.84-89
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• 2008

In a wireless channel above microwave frequency, rain attenuation is very important. In order to predict rain attenuation, 1-min. rain rate distribution is required. This paper discusses appropriate conversion methods to estimate 1-minute rain rate from that of other integration time. Based on the measurement data filed in ITU-R WP3J including ETRI data for 6 consecutive years, distributions of rain rate with 1-, 5-, 10-, 20-, 30-minute integration time were analyzed, both on the global and regional basis, and the parametric relationship between the statistical characteristics of 1-minute and other measurement data were investigated to deduce the conversion methods. It is shown that the global model works good with good accuracy for 5-, 10-, 20-min integration time, and the global model is also applicable globally with good accuracy for 5-, 10-, 20-min integration time. The global conversion model was adopted last year as an ITU-R document for new recommendation. The regional conversion model would also be very useful for locations of similar climatic zone.

• Journal of Korean Library and Information Science Society
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• v.45 no.3
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• pp.93-117
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• 2014

The goal of this study is to seek for the method of effective DB conversion and related system development for the integrated KORMARC Format on the basis of the case of Sogang University Library. Since the integrated KORMARC bibliographic format was established, libraries have been converting bibliographic DB according to the new format. Loyola Library of Sogang University internally proceeded DB conversion using bibliographic DB convertor, which was developed and customized with a system vendor for Sogang University Library. The internal conversion enabled to correct or supplement bibliographic data errors. Besides, it enhanced stability of conversion and shortened the project time by adopting sampling conversion method. It was effective to reduce the additional work for DB quality maintenance, so this kind of conversion is recommendable to the library that has limited manpower for manual data correction.