• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.6
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• pp.571-579
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• 1987

The integral equations used in electromagnetic fields theory can be used for scattering problems. We can obtain various characteristics of scatterer. Ie, power pattern, scattered field, by finding current distribution on the scatterer. In this paper, current distribution on polygonal cylinder is obtained using integral equations in 2 dimension. For numerical aualysis, the moment method is used with pulse function as a basis function and integral equation is used with extrapolation method, which saves cpu time.

• Asia pacific journal of information systems
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• v.5 no.1
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• pp.186-218
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• 1995

The necessity of installing well adaptable Information Systems are required day by day in all the fields of business management. This paper provides an Information System development for enhancing competitive power of the small and medium-sized firms in Korea. Recent growing Information Technology leads to constructing invisibly some new adaptable Information Systems in accordance with the business size, level, capacity and requirements. Even though some advanced companies and big enterprises are already operating their own appropriate Information Systems so as to get their remarkable productivity at a moment. The rest of those small firms are still trying to find out some proper systems fitting their own business in very poor situations. The basic requirements of the points of views by mail questionaired and interviewed from 1292 small and medium-sized manufacturing firms reflected on this Information System development. As a result, the study introduces some economically efficient, convinient, flexible and useful applied Information Systems with simple methods.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06c
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• pp.258-261
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• 2011

Living in the age of information people face problems related to information overload. Information is easy to produce, store and distribute through various communication channels, one of which is emails. With the appearance of the mobile devices, such as smart phones and tabs, people can have access to email inbox at any moment of time from everywhere. In this paper we present information extraction system with a specific goal of extracting meeting location from the announcement of seminar or conference. We apply a machine learning method (conditional random fields, CRF), train the system using annotated corpus of seminar and conference announcements and validate results by applying various extracted correction rules and patterns. Furthermore, we normalize extracted location, and reference using geo-coding databases, OpenStreetMap and Wikipedia resources to determine real geographical coordinates.

• Journal of electromagnetic engineering and science
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• v.7 no.2
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• pp.59-63
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• 2007

This paper suggests a novel method to efficiently calculate the spatial-domain Green's functions of 2D electromagnetic problems Briefly speaking, this method combines spectral and spatial domain calculation schemes and prevents the Green's functions from poor convergence due to the singularities that complicate the process of the Method of Moment(MoM) applications For the validation of this proposed method, fields will be evaluated along the spatial distance including zero distance for 2D free-space and periodic homogeneous geometry The numerical results show the validity of the prosed method and correspondng physics.

• Journal of Magnetics
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• v.9 no.4
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• pp.113-115
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• 2004

The magnetization properties have been measured for amorphous $Fe_{82}Mn_{8-x}B_xZr_{10}$ (x = 0-8) alloys. The temperature dependence of magnetization for these alloys shows the existence of antiferromagnetic couplings between Fe atoms in low fields at low temperatures. The magnetic parameters, obtained from the magnetization behavior are consistent with the presence of mixed magnetic state. The Curie temperature and magnetic moment increased with an increase of the concentration of B and spin glass like transition observed at low temperature decreases and finally vanishes at x = 8 at %. Our result suggests that the substitution of B for Mn seems to cause an increase of magnetic order.

• Journal of Aerospace System Engineering
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• v.4 no.4
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• pp.18-27
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• 2010

Quadrotor is an aircraft which is possible in Vertical Take-off and Landing(VTOL). This aircraft can not only be created as an Unmanned Aerial Vehicle(UAV), but also can be easily used in various fields because of its simplicity of construction. This study is mainly conducted with two main purposes. The first goal is designing the quadrotor focusing on the lightweight and protecting the airframe. The second purpose is stabilizing the quadrotor's attitude by using the PID controller. MATLAB simulation is performed for obtaining PID gain based on equations of motion. We used the compensation filter technique for the calibration of sensor data. PID gain has been drawn out based on the MATLAB simulation. The efficiency of the attitude control is improved by calibration of sensor data.

• Mycobiology
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• v.30 no.2
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• pp.70-75
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• 2002

The mycelia were directly isolated from eight species of fungal basidiocarps, confirmed to the ectomycorrhiza in the roots from the fields(forestry); Suillus bovinus, Paxillus involutus, Lactarius hysginus, Russula fragilis, Lepista nuda, Lyophyllum shimeji, Tricholoma matsutake, and Russula integra. The mycelia were pure-cultured with several transferring in various agars, and inoculated to the roots of pine(Pinus densiflora) seedling by in vitro method. After ten months growth under artificially aseptic conditions, all pine seedlings inoculated were stimulated at the growth-height, whereas those not inoculated were nearly dead. Also, the ramifications of ectomycorrhizal pine roots formed in the synthetic in vitro systems and were various according to the different mycelia. Synthesis of ectomycorrhiza were clearly confirmed in ten months growth, but not distinguished at this moment. It was clearly proved that the mycelia isolated caused the ectomycorrhizae in the roots of pine seedlings.

• Honam Mathematical Journal
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• v.31 no.4
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• pp.505-513
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• 2009

Let {$X_k;k{\in}N^d$} be centered and identically distributed random field which is asymptotically negative dependent in a certain case. In this note we prove that for $p{\alpha}$ > 1 and ${\alpha}$ > ${\frac{1}{2}}$ $E{\mid}X_1{\mid}^p(log^+{\mid}X_1{\mid}^{d-1})$ < ${\infty}$ if and only if ${\sum}_n{\mid}n{\mid}^{p{\alpha}-2}P$($max_{1{\leq}k{\leq}n{\mid}S_k{\mid}}$ > ${\epsilon}{\mid}n{\mid}$) < ${\infty}$ for all ${\epsilon}$ > 0, where log$^+$x = max{1,log x}.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.508-514
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• 1997

RCS system consists of RC columns and Steel girders. Because RC columns are useful for compression and steel girders are for bending moment, RCS system has good structural performances. This system, however, has had no verification in the onstruction fields. This paper is a feasibility study on RCS system to verify the structural and economic efficiency of RCS system. On this study, we analyze 18 models selected by existing building data survey, and design these models as steel system,SRC system (Steel + RC system) and RCS system. To verify the economic efficiency of RCS system, we estimate the columns of these models. And we predict the construction procedure of RCS system to compare construction duration of RCS system with others So, in this study we find that RCS system is more economic than steel system and SRC system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.63-67
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• 2000

In this paper, the electromagnetic interference of a parallel plate with apertures is characterized by the method of moment(MoM), using the Spline-type Divided-Difference Interpolation(SDDI) technique. Particularly, for the solution of the problem, the application of the SDDI technique is extended to the calculation of the summation-type Green's functions. It improves numerical efficiency, having accuracy and saving the overall computational time required in the MoM application. For validating the proposed method, the electric fields on the apertures are calculated and compared to those of the literature. The numerical results show good agreement with them.