• Journal of the Institute of Electronics Engineers of Korea SC
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• v.49 no.4
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• pp.45-54
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• 2012

Location-based services with GPS positioning technology as a key technology, but recognizing the current location through satellite communication is not possible in an indoor location-aware technology, low-power short-range communication is primarily made of the study. Especially, as Chirp Spread Spectrum(CSS) based location-aware approach for low-power physical layer IEEE802.15.4a is selected as a standard, Ranging distance estimation techniques and data transfer speed enhancements have been more developed. It is known that the distance measured by CSS ranging has quite a lot of noise as well as its bias. However, the noise problem can be adjusted by modeling the non-zero mean noise value by a scaling factor which corresponds to the change of magnitude of a measured distance vector. In this paper, we propose a localization system using the CSS signal to measure distance for a mobile node taken a measurement of the exact coordinates. By applying the extended kalman filter and least mean squares method, the localization system is faster, more stable. Finally, we evaluate the reliability and accuracy of the proposed algorithm's performance by the experiment for the realization of localization system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.761-768
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• 2010

This paper presents an effective method to achieve the wideband waveform for high resolution SAR(Synthetic Aperture Radar) using the frequency multiplication technique. And also this paper analyzes the root causes for the spectral regrowth due to 3rd-order intermodulation in chirp bandwidth expansion scheme using quadrature modulator and frequency multipliers. The amplitude and phase imbalance requirement are defined based on the simulation results in terms of quadrature channel imbalance. This minimizes the degradation of range resolution, peak sidelobe ratio and integrated sidelobe ratio. The wideband chirp generator using the frequency multiplier and memory map scheme was manufactured and the compensation technique was presented to reduce the spectral regrowth of SAR waveform by minimizing the amplitude and phase imbalance. After I and Q channel imbalance adjustment, the carrier level reduces －28.7 dBm to －53.4 dBm. Chirp signal with 150 MHz bandwidth at S-band expands to 600 MHz bandwidth at X-band. The sidelobe levels are reduced by about 8 to 9 dB by compensating the amplitude balance between I and Q channels.

• Journal of Korean Historical Folklife
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• no.28
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• pp.113-142
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• 2008

The purpose of this script is to understand general issues related to production of visionary drawing and correct the fault of previous research by examining the data on visionary drawing featured on Ok So Kwon-Seop's anthology, "Oksogo(玉所稿)" the summary of its contents are as follows. First by analyzing the status of visionary drawings, in among "Oksogo(玉所稿)" which is Ok So's manuscript collection, there are 56 pieces in Je Chun Bon (edition) and 47 in Moon Kyoung Bon(edition). And recorded dreams in visionary drawings are centralized when Ok So was in his late 50's to 70's. And it is estimated that the visionary drawings are the collection of work done by many artists in long period of time. It was confirmed that Kwon Seop himself did not participated in drawings but were done by his brother Kwon Young, his grandson Kwon Shin Eung and Cho Se Gul, the artist from Pyoung Yang. Also visionary drawings were produced in youth years and among the visionary drawings that can be ascertain about the produced year and the oldest is by Cho Se Gul which was estimated to be done in 1695. And the last one to be completed was which was a dream in 1756 turned into a drawing and this was produced between 1756 to 1759 which was a year Ok So passed away. Production of Ki Seung Chup (album) or Mong-Wha Chup (album) was accomplished as follows. When Ok So records his dream in writing he receives response poem from a person he was in dream with and ask artist to draw the vision in dream, then the drawing and scripts were compiled and made into an album. With this some of the issues on visionary drawings featured on "Oksogo(玉所稿)" would have been settled. Recently, 2 more volumes of Ok So's anthology were photo-printed and published and hopefully those issues that was unable to settle in this script will have more detailed answers by discovering new and undisclosed data.

• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.91-98
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• 2023

Genre paintings, which describes the lives of ordinary people, has lifestyle and Pungnyu of our ancestors. Pungnyu is aesthetic consciousness and a way of lives. The culture of Pungnyu is a kind of art boundary that combines high spirits and art. The Pungnyu is an icon of Korean culture, realization of taste, and happens through "stroll", which means the walking peacefully, and "sightsee", which means go sightseeing. It shows through the rambling and the excursion. Hyewon's 'Jeonsincheob'('傳神帖', a kind of spirit transferred drawings book) is a genre painting which represents Pungnyu and shows various activities at that time. Therefore, we can understand our own spirit and soul through appreciating his paintings. Hyewon's 「Jeonsincheob」 has three special features. Firstly, it is the symbol of Korea traditional Pungnyu. Secondly, it contributes to development of the East art. Lastly, Hyewon's 「Jeonsincheob」 can be considered in terms of glocalism, which means the combination of globalization and localization and can be explained by the relation of the center=the periphery, the globalization=the Korean wave, the universality=the particularity. Hyewon's 'Jeonsincheob' has aesthetic boundaries. One aims at individual pleasure. Another aims at harmony with its natural environment in which you are. Also, it can be considered as the boundaries of enjoying together which aims at harmony with social environment among group members.

• The Science & Technology
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• v.30 no.1 s.332
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• pp.32-34
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• 1997

1861년 대동여지도를 만든 김정호는 어디서 태어나 언제 죽었는지도 모르는 신비 속의 인물이다. 지금의 마포 근처에서 살았다는 김정호는 22첩으로 된 가로 3m, 세로 7m의 대동여지도를 목판으로 인쇄하여 펴낸 과학인물이다. 대동여지도는 지금의 16만분의 1지도와 비슷한 것으로 산, 하천, 고을, 길 등이 정확하게 표시되어 있다. 평생을 지도제작에 바친 그의 뛰어난 과학정신이 새롭게 평가되고 있다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.349-350
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• 2001

엷은재첩 Corbicula papyracea (Heude)은 이치아강 (Heterodonta) 백합목 (Veneroida) 재첩과(Corbiculidae)의 패류로 모래가 많은 진흙 바닥에 서식한다. 소형종으로 옅은 황갈색 바탕에 녹색을 띠고 있다 각폭이 엷으며 성장맥이 나늘고 폭이 좁아 조밀하다. 패각의 내면은 보라색 또는 진한 보라색을 띠고 있다. 개체수가 많지 않다. 난태생을 하며, 전국적으로 분포한다 (권오길 외). (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.192-193
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• 2001

높은 파장 선택도를 가지고 광신호를 제어하는 광섬유격자는 단주기 격자, 장주기 격자, 첩 격자 등이 있는데 이러한 격자의 제작 기술은 여러 응용분야에서 활용도 높은 소자를 제작하는 데 이용되어져 왔다. 본 논문에서는, 주어진 반사 파장 내에 매우 좁은 선폭의 여러 투과 스펙트럼 밴드를 가지며 그 응용성이 다양한 격자 제작을 목표로 이미 수행되어진 위상천이 격자의 시뮬레이션[1]을 토대로 $\pi$위상천이 격자를 제작하였다. (중략)

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.172-173
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• 2001

다중 광접속 방법 중 CDMA는 많은 수의 주소(개별 사용자를 위한 채널)를 제공하고 광 패킷 전송 방법에 있어서는 패킷들의 충돌을 피하기 위한 복잡한 장치를 필요로 하지 않는다는 장점을 가지고 있다. LED와 같은 Incoherent 광원을 이용하는 광 CDMA를 위한 여러 가지 광 코드와 암호화 방식이 제안되어 왔으며, 파장/시간 이차원 광 코드를 이용하는 방식은 AWG mux/demux 또는 AWG 라우터를 이용하여 광 코드가 용이하게 구현될 수 있음이 보고된 바 있다. (중략)

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.7
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• pp.488-498
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• 2007

This paper presents a novel approach for representing the spatio-temporal topology of the camera network with overlapping and non-overlapping fields of view (FOVs) in Ubiquitous Smart Space (USS). The topology is determined by tracking moving objects and establishing object correspondence across multiple cameras. To track people successfully in multiple camera views, we used the Merge-Split (MS) approach for object occlusion in a single camera and the grid-based approach for extracting the accurate object feature. In addition, we considered the appearance of people and the transition time between entry and exit zones for tracking objects across blind regions of multiple cameras with non-overlapping FOVs. The main contribution of this paper is to estimate transition times between various entry and exit zones, and to graphically represent the camera topology as an undirected weighted graph using the transition probabilities.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.2
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• pp.218-225
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• 2015

Inverse synthetic aperture radar(ISAR) is coherent imaging system formed by conducting signal processing of received data which consists of radar cross section(RCS) reflected from maneuvering target. A novel algorithm is proposed to compensate inter-pulse motion(IPM) for the purpose of forming an well-focused ISAR image through signals generated by stepped chirp waveform( SCW). The velocity and acceleration of the target related to IPM are estimated based on particle swarm optimization (PSO) which has been widely used in optimization technique. Furthermore, a modified PSO which enables us to improve the performance of PSO is used to compensate IPM in a very short-time. Simulation results using point scatterer model of a Boeing-737 aircraft validate the performance of the proposed algorithm.