• The Journal of the Acoustical Society of Korea
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• v.15 no.1
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• pp.40-45
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• 1996

In this paper, a nonlinear optimal design technique is presented to find an optimal beam pattern. With this technique, the beam width is minimized with respect to a given maximum allowable side-lobe level considering the self- and mutual radiation impedances of vibrators. The proposed method is applied to design a planar array consisting 37 vibrators which are symmetric in X, Y and $45^{circ}$ axes. The results show that significantly low side-lobe level maintaining a main beam width can be obtained using this method.

• The KIPS Transactions:PartB
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• v.8B no.4
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• pp.335-342
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• 2001

본 논문은 보로노이 공간분류를 활용하여 원격탐사 영상인식을 위한 다층 신경망 분류기를제안한다. 제안된 다층 신경망 분류기는 보로노이 다각형 영역으로 클래스를 구분하며, 초평면 방정식의 계수를 오류 역전과 학습 초기의 연결 강도, 임계치 그리고 은닉층의 노드 수로 결정한다. 제안된 방법은 오류역전과 학습 알고리즘에서 임의로 정해주던 초기 정보를 사전 분석에 의해 공학적으로 결정함으로써 느린 수렴 속도와 학습실패 등의 단점을 피할 수 있는 장점이 있다. 보로노이 다이어그램에 대한 경계선의 초평면 방정식은 훈련집합의 클래스별 평균값을 구하여 Mathematica 패키지로 계산하였다. 제안된 다층 신경망에 의한 영상분류기의 인식능력을 평가하기 위하여 원격탐사 영상인식에서 자주 활용되는 최소거리 분류 방법과 최대우도 분류 방법으로 처리해서 비교한 결과, 최소거리 분류 방법은 실험화상에 대해 81.4%, 최대우도 부류기에 의한 분류는 87.8%, 제안한 방법은 92.2% 정확성을 가진 분류결과를 나타냈다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.1018-1024
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• 2001

In this paper, an array antenna is designed far base station of a street micro-cell in urban areas. It has a rectangular radiation pattern. The current distribution of the array is decided by using a modified Woodward-Lawson sampling pattern synthesis method. To confirm the realization of the array antenna with rectangular pattern, 12 array antenna with a planar type monopole fed by stripline is fabricated and measured. In the results of the measured values, H-plane pattern of the antenna nearly yields a rectangular radiation pattern.

• Proceedings of the Korea Multimedia Society Conference
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• 2000.11a
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• pp.475-478
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• 2000

사람의 몸 동작을 인식해야하는 여러 응용분야에서의 필요성이 대두되면서 이 분야로의 연구가 활발해지고 있다. 이 논문은 사람의 비언어적 행동을 자동적으로 분석할 수 있는 인식기 개발에 관한 것으로 실세계 3 차원 좌표값을 입력으로 하는 사람 몸 동작 패턴 분류기의 구현방법을 소개한 것이다. 하나의 사람 몸 동작은 각 몸 구성 성분(손, 아래팔, 위팔, 어깨, 머리, 몸통 등)의 움직임을 조합해서 정의한 수가 있기 때문에 개별적인 각 몸 구성성분의 움직임을 인식하여 조합해서 임의의 동작을 판별하려는 방법을 적용한다. 사람 몸 동작 패턴 분류기는 측정된 실세계 3 차원 좌표 자료를 양자화한 후 xy, zy 평면에 투영한 값을 자자 구한다. 이 결과를 각각 8 방향 체인 코드로 바꾸고 2 단계 체인 코드 평활화 사업을 하여, 4 방향 코드 체적화 및 대표 코드로의 압축단계를 거친다. 이로서 생성된 프리미티브 패턴나열들을 동작 클래스별로 분류하여 프리미티브 패턴나열의 확장으로 각각의 식별기를 구축하여 각 몸 구성 성분별 동작들을 분류한다. 일련의 실험이 행해져 그 타당성을 확인하였으며, 차후에 이 분류기는 비언어적 행동 분석을 위한 사람 몸 동작 인식기의 전처리 단계로 사용되어진 것이다.

• The Research Journal of the Costume Culture
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• v.27 no.6
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• pp.599-614
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• 2019

The aim of this study to provide basic reference data for the development of video contents used in pattern drafting education and to explore the possibility of utilizing YouTube videos in such education. Subject videos were selected using the number of views. A total of 596 videos and 28 channels were analyzed for the period July to September 2019 and the results are as follows. With regard to content, there were 27 pattern drafting items, the majority being dress, pants, skirt, blouse and sleeve drafting, although high-level content such as cowl, bustier, corset patterns were also available. Therefore, there is a high likelihood that YouTube videos could be used as educational material, especially as supplementary references to provide specific examples and easy explanations for difficult concepts or method, for students majoring in this field. However, as most videos currently focus on a few items, expanding video content to features a wider variety of clothing items at different levels is necessary. With regard to video length, it mostly ranged from 10 to 15 minutes. It is not advisable to create lengthy lecture-style videos expounding on different principles or variations in pattern drafting when developing educational video material.

• Journal of the Korea Fashion and Costume Design Association
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• v.18 no.2
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• pp.101-113
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• 2016

This study was conducted in order to analyze draping and flat pattern according to jacket design, and provide basic materials for developing a jacket pattern that can enhance fitness, functionality, and aesthetic expression of clothes by reflecting esthetic expression of draping and efficiency of flat pattern at the same time. For the experimental jacket designs of a one-piece sleeve jacket and a two-piece sleeve jacket were selected among the entries of the designer Rubina for 2014 F/W Seoul Fashion Week. Designer brand Rubina usually produced clothes using draping and the designer brand company provided the experimental patterns for the study. We also had flat patterns of the same design and size specifications designed by a flat patternmaker who has 30 year-experience in flat pattern like Rubina. The test apparel jacket was made of 20's cotton yarns. Three models wore the jackets and evaluation on appearance fitness was conducted by 7 members in an expert panel group from August 10, 2015 to September 10, 2015. As a result of appearance fitness analysis on one-piece sleeve jacket, there were significant difference in 4 items among 17 items in terms of overall appearance. The appearance of jackets by draping had higher score than those using flat pattern. As for two-piece sleeve jacket, there were significant differences in 7 items among 17 items related to overall appearance. As for the items related to sleeve, 5 items out of 13 showed significant differences. Except for one item, appearance of jackets using draping had higher score than flat pattern. As for motion fitness, draping was evaluated to be more comfortable. Applying the items with high scores in appearance and motion fitness in draping to flat pattern, The study suggests a new jacket pattern development that would increase the satisfaction of consumers for future research.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.2
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• pp.257-262
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• 2017

In this paper, we proposed a rectangular planar monopole antenna with a double sleeve that applied to a half-cut and a discontinuous feed structure. A rectangular planar monopole antenna with a double sleeve was cut in half along the magnetic symmetry line, and impedance matching was achieved by a discontinuous structure was applied to a feeder and by adjusting the double sleeve gap. We used the HFSS simulator of ANSYS company to confirm the antenna parameter property, and the antenna size was $21{\times}40mm^2$. In the proposed antenna, the simulation frequency range with VSWR of 2 or less was 2.6GHz to 10.25GHz. The bandwidth was 7.65GHz. The frequency range of the fabricated antenna was 3.3GHz to 9.75GHz, and the bandwidth was 6.45GHz. The measured radiation pattern frequencies were 3.5GHz, 5.5GHz, 7.5GHz, and 9.5GHz. A radiation pattern similar to the dipole antenna pattern was obtained at all frequencies.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.5
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• pp.502-507
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• 2013

In this paper, a circular dual mode horn with modified aperture is proposed to improve a E/H-plane radiation pattern symmetry of a conventional oversized circular dual mode horn. The proposed antenna consists of a feeding section, a mode generation section and a phase matching section which has aperture shape transition from circle to ellipse or rectangle to improve a E/H-plane radiation pattern symmetry. To compare the performances between the proposed antenna and the convenional circular dual mode horn, the conventional circular dual mode horn and the proposed circular dual mode horn with rectangular aperture are fabricated and researched at 15 GHz. The measured results show that the conventional circular dual mode horn has 3.394 dB difference while the proposed antenna has only 0.539 dB difference between E and H-plane radiation patterns within the -11 dB beamwidth($53^{\circ}$) which is required beamwidth of the feed horn for the maximum aperture efficiency where f/d ratio of reflector antenna is 1.

• The Journal of the Acoustical Society of Korea
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• v.33 no.3
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• pp.200-209
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• 2014

In this paper, we present a general model for synthetic transmit focusing method using plane waves (STF-PW) of which the properties are investigated through mathematical analysis and compared with those of the conventional focusing method. The analysis results show that STF-PW produces non-diffracting beams in the sense that their main lobe widths do not change with depth. We also present a method for synthesis of plane waves to obtain a desired main lobe width while preventing grating lobe generation and a method for broadening the region over which the non-diffracting property is maintained. The proposed model and analysis results were validated through computer simulations.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.612-620
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• 2008

In this parer, parabolic edge planar monopole antenna for UWB communication is presented. The antenna have broadband property structurally through planar monopole and ground which have parabolic edge. It is designed close to self-complementary structure as changing curvature of edge of monopole and ground. Monopole and ground of proposed antenna exist on coplanar plane, and excite as coaxial feeding. It used FR4 dielectric substrate of ${\varepsilon}_r=4.4$, and the size is $26{\times}31{\times}1.6mm$. Return loss is more than 10 dB in $3.1{\sim}10.6GHz$. Radiation pattern is about the same that of dipole antenna at all frequency. At measured result, max gain is $1.37{\sim}6.02dBi$ at E-plane.