• 대한공업교육학회지
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• v.38 no.2
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• pp.176-194
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• 2013

In this research, 'Construction Technology and Environment' units in 12 different technology home economics textbooks for 1st~3rd year middle school students under the 2009 Revised Educational Curriculum and the content system of textbooks were analyzed based on Reigeluth's elaboration theory, and the following conclusions were derived. First, each of the 12 different textbooks presented the elaboration process by procedural method and composed the content system. Second, the 'Construction Technology and Environment' unit presented many 'Thought Opening' as the systematization strategy of advance learning ability, and 'Unit Summary' presented at the end of the unit as the use strategy of the summarizer was presented preponderantly. In addition, 'Learning Objective' that represents the degree of achievement of the students after learning the unit was presented most as the use strategy of the synthesizer although there are differences in terms. In all of the textbooks, 'Figure,' 'Table,' 'Diagram', and 'Explanation of Terms' were used, and particularly, in the vitalizer strategy of the cognitive strategy, overwhelmingly greater number of 'Figure's, compared with all other elements, were presented as the vitalizer strategy of cognitive strategy. Finally, 'Compensatory Learning,' and 'In-depth Study' were presented as the learner control strategy in each of the 4 different textbooks, and there was one textbook that presents the term 'Supplement Reinforcement' in which compensatory learning and in-depth learning were integrated. Third, the metaphor utilization strategy among the 7 teaching strategies of the elaboration theory was hardly used in the composition items in units of textbooks.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.2
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• pp.30-39
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• 2019

In this study, 27 representative plants with symbolism and appreciation were extracted from 68 plants collected in Li Yu (1611-1680)'s monograph named 'Xianqingouji Zhongzhibu'. The interpretations were as follows. First, symbolism of plants could be summarized as 1) Li Yu thought that Paeonia suffruticosa was called 'the king of flowers', not only because of its beauty, but also because of its upright character. The only flower that could compete against Paeonia suffruticosa was Paeonia lactiflora Pall.. This flower was called 'the flower prime minister' by common people. But Li Yu thought that Paeonia lactiflora Pall. should also be included in the feudal princes. 2) Prunus persica and Camellia japonica were compared to 'beautiful cheeks', and Malus spectabilis (Ait.)Borkh, Jasminum sambac, Rosa multiflora var. platyphylla, Narcissus tazetta, Papaver rhoeas were compared to 'beautiful women', expressing his love for flowers. 3) Li Yu called Nelumbo nucifera a 'gentleman in flowers' and Buxus sinica Rehd. et Wils. Cheng a 'gentleman in trees'. On the contrary, Daphne odora was compared to 'villain in flowers'. 4) Ilex integra was compared to a hermit, and Campsis grandiflora was compared to an immortal. Second, appreciation of plants could be organized by 1) Appreciation of plants required assistive tools. When going to suburb to enjoy the scenery, tents needed to be prepared. Paper screens should be used to appreciate Prunus mume in the courtyard so as to gain more elegant. Li Yu also proposed that ornamental objects should be properly placed near Orchidaceae so as to gain more elegant. 2）Li Yu took Lagerstroemia indica and Prunus armeniaca L. as examples to interpret that plants were as perceptive as animals and human beings. 3) Li Yu took Salix pierotii and Albizia julibrissin as examples to interpret that people should communicate with plants through five senses to produce resonance. And took Nelumbo nucifera and Rosa rugosa to emphasize the ornamental and practical value of plants. 4) Plants were metaphored sth. similar to them. An interesting example was Celosia cristata L. which was more like an auspicious cloud in the sky than the crest on the cock's head. To sum up, Li Yu personified plants and thought that people should communicate with plants by multi-sensory world when appreciating plants. Through this, it fully showed his love for plants. Meanwhile, Li Yu's symbolism and appreciation of plants, to some extent, reflected the elegant life of literati in the early Qing Dynasty.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.226-229
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• 2007

본 논문에서는 사각형 링을 갖는 UHF대 RFID 리더기용 소형 원편파 패치 안테나를 설계 제작하였다. 정사각형의 패치 안테나를 설계하고, 원편파를 위한 Truncated 패치 안테나를 설계한 후, 소형화를 위해 사각형의 링을 갖는 Truncated 패치 안테나를 설계하였다. 주파수 대역은 UHF대역인 902928MHz이며, 설계를 위하여 HFSS simulation올 사용하였다. 비유전율 4.3, 두께 1.6mm, 손실탄젠트 =0.019의 epoxy 기판을 사용하여 실현하였다. VSWR, 방사이득, RHCP, LHCP의 큰 변화없이 사각형의 링을 이용하여 기본 Truncated 안테나보다 6.37% 소형화시켰다.

• 전기의세계
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• v.28 no.7
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• pp.21-24
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• 1979

전력의 발생에서 말단의 배전에 이르기까지의 전력 Energy의 흐름을 전력 System이라면 이것을 주회로계통과 제어계통으로 나누어 볼 수 있다. 물론 양자는 일체가 되어 전력 System을 형성하고 있지만 이것을 인체에 비유하면 제어계통은 신경계통에 상당한다. 주회로계통 즉 발전기, 변압기, 차단기나 송전선등 주기기는 전력계통의 경제성추구에 따라 년년 그 단위기용량의 증대와 전압계급의 상승등 눈부신 개발과 연구로 발달되어 왔고, 한편 제어계통도 전자기술의 진보로 어떤면에서는 주회로기기보다도 더 크게 발달되도 있다. 전력수요의 증대에 따라 질, 량 양면에서의 써비스 요청은 더욱 고도화하여 설비의 근대화, 자동화등에 의한 공급신뢰도향상이 한층 더 필요해졌기 때문이다. 초기에는 제어는 사람이 기계에 붙어서 그 기계를 눈으로 보면서 행하였지만, 단위운전원이 조작가능한 설비용량에는 한계가 있어서 원방제어, 집중제어, 자동화의 방향으로 목표가 진행되어 완전무인화의 방향으로 나아가고 있다. 앞으로 외국에 비해 다소 늦긴했으나 전자계산기의 도입설치에 의한 계산기제어및 관할 배전변전소군의 원방감시제어에 의한 무인화등이 검토될 것으로 기대된다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.553-555
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• 2003

e-Learning 컨텐트 설계에 있어 객체지향기법에 근간한 학습객체 기반 설계에 많은 관심이 모아지고 있다. 학습객체는 기존의 컨텐트가 하나의 커다란 덩어리로 이루어져 있어 동일한 내용에 관해서도 많은 코스들이 생성되었던 재사용성의 문제를 해결하며 상호운용성, 접근성. 내구성 등의 잇점을 제시하고 있다. 이러한 학습객체는 레고모형에 비유되어 각각의 학습자마다 서로 다른 조합의 코스를 제공한다고 하지만, 현재의 시퀀싱된 형태는 CBT 수준의 분기수준에 머물러 있다. 본 연구에서는 개별화 학습을 지원할 수 있는 시퀀싱 설계를 위하여 학습객체 구조의 관점에서 접근하며, 이러한 학습 설계에 기초가 되는 학습객체의 기본 구조를 제안하고자 한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.83-88
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• 2020

In this paper, H-polarized electromagnetic scattering problems by a conductive strip grating between a grounded double dielectric layer are analyzed by applying the FGMM(Fourier-Galerkin Moment Method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients, and the conductive boundary condition is applied to analysis of the conductive strip. The numerical results for normalized reflected power are analyzed by according as the width and spacing of conductive strip, the relative permittivity and thickness of the grounded double dielectric layers, and incident angles. Generally, as the value of the dielectric constant and dielectric thickness of a grounded double dielectric layer increases, the reflected power increased. And as dielectric thickness of a grounded double dielectric layer increases, the current density induced in the strip center increases. The numerical results for the presented structure of this paper are shown in good agreement compared to those of the existing papers using the PMM(Point Matching Method).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.172-172
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• 2009

$BaTiO_3$는 perovskite 구조를 가지는 대표적인 강유전체 재료로서 MLCC(Multi Layer Ceramic Capacitor), PTC thermistor등에 널리 사용되어지고 있다. 최근 고용량 MLCC 의 상업화와 함께 나노크기를 갖는 tetragonal phase의 $BaTiO_3$ 입자를 합성하기 위한 다양한 제조방법이 제시되고 있다. 또한 유전 특성과 온도특성 및 신뢰성을 향상시키기 위해 많은 첨가제들이 연구되어지고 있다. 따라서 이 번 연구에서는 선행 연구를 통해 얻어진 high energy mill을 이용한 고상반응법으로 제조된 $BaTiO_3$를 사용하였으며, 제조된 $BaTiO_3$ 분말에 glass frit를 첨가하여 소결온도 및 유전특성의 변화를 관찰하였다. 제조된 $BaTiO_3$ 분말은 200nm이하의 구형화와 균일한 입자크기를 보였으며, 선행연구를 통해 최적화된 glass frit의 양인 2.53wt%를 첨가하였고 1170, 1200, $1230^{\circ}C$에서 소결하여 소결온도에 따른 변화를 관찰하였다. 실험방법으로는 원료를 혼합하기 위하여 24시간 ball-mill을 이용하여 혼합하였으며, $\Phi15$로 성형하여 소결을 진행하였다. 실험진행 결과 모든 시편에서의 비유전율은 glass frit가 첨가되지 않은 조성보다 높게 나타났으며, $1200^{\circ}C$에서 소결한 시편의 비유전율($\varepsilon_r$)은 2300으로 glass frit가 첨가되지 않은 조성과 비교하여 21% 증가하여 최대치를 나타냈다. 또한 소결온도 $1200^{\circ}C$ 이상에서의 모든 시편에서는 95% 이상의 상대밀도를 나타내어, glass frit가 소결조제로써의 역할을 하는 것으로 나타났다. 따라서 본 연구를 통해 glass frit첨가로 인한 소결온도 감소 및 유전특성이 증가하는 것을 확인 하였다.

• The Journal of Information Technology
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• v.4 no.3
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• pp.77-86
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• 2001

In this paper, Electromagnetic scattering problem by a resistive strip grating with 2 dielectric layers on a ground plane according as resistivity of resistive strip, relative permittivity and thickness of dielectric layers, and incident angles of a electric wave is analyzed by applying the PMM (Point Matching Method) known as a numerical procedure. The scattered electromagnetic fields are expanded in a series of floquet mode functions. The boundary conditions are applied to obtain the unknown field coefficients and the resistive boundary condition is used for the relationship between the tangential electric field and the electric current density on the strip. According as the relative permittivity and the thickness of layers are increased, the values of the geometrically normalized reflected power have a high value and the values of strip width are moved toward a high value going from left to right. When the resistivity of this paper has a value of zero, the numerical results of the geometrically normalized reflected power show in good agreement with those by the PMM of existing paper. Then, the most energys of the sharp variation point in minimum values of the geometrically normalized reflected power are scattered in direction of the other angles except incident angle.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.9A
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• pp.913-919
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• 2006

In this paper, TE(transverse electric) scattering problems by a resistive strip grating over grounded dielectric multilayers according to the strip width and grating period, the relative permittivity and thickness of dielectric multilayers, and incident angles of a TE plane wave are analyzed by applying the FGMM(Fourier-Galerkin Moment Method) known as a numerical procedure. The induced surface current density is simply expanded in a Fourier series by using the exponential function as a simple function. Generally, the relected power gets increased according as the relative permittivity and thickness of dielectric multilayers gets increased, the sharp variations of the reflected power are due to resonance effects that take place and were previously called wood's anomallies$^{[7]}$. To verify the validity of the proposed method, the numerical results of normalized reflected power for the uniform resistivity R = 0 as a conductive strip case show in good agreement with those in the existing paper.

• Journal of Advanced Navigation Technology
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• v.10 no.3
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• pp.198-204
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• 2006

In this paper, TE(transverse electric) scattering problems by a resistive strip grating on a grounded dielectric plane according to the strip width and grating period, the relative permittivity and thickness of dielectric layer, and incident angles of a TE plane wave are analyzed by applying the FGMM(Fourier-Galerkin Moment Method) known as a numerical procedure. The induced surface current density is simply expanded in a Fourier series by using the exponential function as a simple function. The reflected power gets increased according as the relative permittivity and thickness of dielectric multilayers gets increased, the sharp variations of the reflected power are due to resonance effects were previously called wood's anomallies[7]. To verify the validity of the proposed method, the numerical results of normalized reflected power for the uniform resistivity R = 0 as a conductive strip case show in good agreement with those in the existing paper.