• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.1
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• pp.189-214
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• 1995

본 연구는 미국의 건축 및 조경공간 형성에 미친 일본문화를 파악하기 위한 기초연구로서, 일본문화 및 공간디자인의 특성과 미국건축 및 조경에 나타난 그 면모에 관한 것이다. 1853년 미국과 일본의 문화교류를 시작으로 일본의 예술과 건축이 미국에 소개되었고, 특히 1893년 Chicago에서 열렸던 Wor1ds Columbian Exposition에서 선보인 일본의 건축물은 당시 미국의 건축가들에게 영향을 주었다. 그후 일본의 공간디인은 건축뿐만 아니라 조경분야에도 영향을 미쳐 현재 미국의 공간디자인을 구성하고 있는 특성 가운데 하나로 자리잡고 있다. 필자는 미국의 공간디자인에 영향을 준 일본문화의 실재를 파악하기 위하여 한국과 중국의 문화와 구별되는 일본만의 독특한 문화적 특성을 고찰해보고, 미국 현대건축의 선구자인 Frank Lloyd Wright, Greece and Greene, Philip Johnson, Richard J. Neutra의 작품 및 조경디자이너인 Ethelbert E. Furlong, James C. Rose의 작품속에 나타난 일본식 공간디자인의 면모를 살펴보았다. 장래 이 분야의 연구에서는 미국문화의 특성이 고찰되어 미국과 일본의 두 문화가 비교 파악되기 위한 개념적 근거가 마련되고, 일본식 공간디자인이 미국에서 어떻게 이해되고 해석되어졌으며 미국식 공간 디자인으로 전환되었는지 살펴보며, 어떤 이유에서 일본의 공간디자인 양식이 미국의 건축 및 조경분야에서 문화적으로 일본보다 오랜 역사를 지닌 한국과 중국의 공간디자인 양식보다 커다란 영향을 주고 있는지에 관해 이해를 구하는 방향으로 연구가 수행되어야 함을 제안한다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.221-224
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• 2005

본 논문에서는 워터마크가 삽입된 데이터의 저작권 보호를 위하여 데이터의 복제 시 신속한 위치추적을 통한 불법 복제 방지 시스템을 제안하고 시뮬레이션 하였다. 제안된 방법은 복사기, 프린터, 스캐너 등에 부착된 워터마크 검출 장치로부터 워터마크 검출 시 원 워터마크 이미지와 추출된 워터마크이미지가 일정 비 이상의 상관관계가 있을 경우 불법 복제 상황으로 간주하고, 디지털 데이터로 변환된 워터마크 이미지와 주소 정보가 전력선을 통하여 전송된다. 수신단에서는 수신된 데이터의 발신자 정보를 통해 위치정보를 알아내어 불법 복제 작업현장의 위치를 추적한다. 전력선을 통신선로로 이용 시 전송신호는 전력선 채널 환경에서 임펄스 잡음에 많은 영향을 받기 때문에 본 논문에서는 제안한 시스템의 검증을 위해 AWGN과 임펄스 잡음을 고려하고 잡음 특성이 우수하고 신뢰성이 비교적 강한 DS-CDMA/BPSK 시스템을 통해 제안된 시스템을 시뮬레이션 하였다. 또한, 열악한 채널 환경으로부터 수신성능을 개선하기 위해 컨벌루션 부호화기법을 적용하여 성능 개선 전 후의 복원 이미지의 성능을 비교 분석 하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.630-634
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• 2005

본 논문은 신경망을 이용한 간섭 신호 제어 복합 다층 퍼셉트론에서 DS/SS 이동 통신에서 수신된 신호를 검출하는 것에 대하여 연구한다. 수신 신호가 일정한 비트율을 갖는 채널에 전송하기 위하여 신경망을 이용한 새로운 탭 가중치 갱신 제어 방법을 제안한다. 적응 횡단선 필터는 상호 심볼간 간섭을 억압하기 위해 LMS 알고리즘 사용하고, 응답과 실제 출력간의 차인 에러를 이용하여 탭 가중치 조절 메카니즘을 통해 탭 가중치를 갱신함으로서 효과적으로 간섭을 제거한다. 본 논문은 상호 심볼간 간섭을 효율적으로 억압해온 다계층 퍼셉트론 조합을 이용하여 제안된 알고리즘을 통해 탭 가중치 갱신이 보다 효율적으로 이루어질 수 있도록 한다. 시뮬레이션을 통해 평균자승 에러의 수렴 특성이 우월하다는 것을 연구한다.

• Journal of Communications and Networks
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• v.5 no.1
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• pp.33-42
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• 2003

In this paper a two-stage maximum-likelihood (ML) detection structure for group detection in DS/CDMA systems is presented. The first stage of the receiver is a linear filter, aimed at suppressing the effect of the unwanted (i.e., out-of-grout) users' signals, while the second stage is a non-linear block, implementing a ML detection rule on the set of desired users signals. As to the linear stage, we consider both the decorrelating and the minimum mean square error approaches. Interestingly, the proposed detection structure turns out to be a generalization of Varanasi's group detector, to which it reduces when the system is synchronous, the signatures are linerly independent and the first stage of the receiver is a decorrelator. The issue of blind adaptive receiver implementation is also considered, and implementations of the proposed receiver based on the LMS algorithm, the RLS algorithm and subspace-tracking algorithms are presented. These adaptive receivers do not rely on any knowledge on the out-of group users' signals, and are thus particularly suited for rejection of out-of-cell interference in the base station. Simulation results confirm that the proposed structure achieves very satisfactory performance in comparison with previously derived receivers, as well as that the proposed blind adaptive algorithms achieve satisfactory performance.

• Journal of Power Electronics
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• v.12 no.6
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• pp.895-903
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• 2012

This paper presents a fast switching direct torque control (FS-DTC) using only a single DC-link current sensor. In FS-DTC, six new active voltage complex space vectors (CSVs) are synthesized by the conventional active voltage space vectors (SVs). The corresponding sectors are rotated in the anticlockwise direction by 30 degrees. A selection table is defined to select the CSVs. Based on the "Different Phase Mode", the output sequence of the selected CSV is optimized. Accordingly, a reconstruction method is proposed to acquire the phase currents. The core of the FS-DTC is that all of the three phase currents can be reliably reconstructed during every two sampling periods, which is the result of the fast switching between different phases. The errors between the reconstructed and actual currents are strictly limited in one sampling period. The FS-DTC has the advantages of the standard DTC scheme such as simple structure, quick torque response and robustness. As can be seen in the analysis, the FS-DTC can be thought of as an equivalent standard DTC scheme with 86.6% of the maximum speed, 173.2% of the torque ripple, and 115% of the response time of the torque. Based on a dSPACE DS1103 controller, the FS-DTC is implemented in an induction machine drive system. The results verify the effectiveness of the FS-DTC.

• Journal of Pharmaceutical Investigation
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• v.16 no.2
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• pp.55-67
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• 1986

Inclusion complexation of tiaprofenic acid (TPA) with cyclodextrins $({\alpha}-,\;{\beta}-,\;{\gamma}-CyDs)$ in aqueous solution and in solid phase was investigated by solubility method, measurement of partition coefficient, ultra-violet, circular dichroism, infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Investigations were made to prepare inclusion complexes of TPA with ${\beta}-CyD$ in solid powdered form by coprecipitation, freeze-drying, spray-drying and co-pulverization methods. The coprecipitation, freeze-drying and spray-drying methods were successful in obtaining inclusion complexes. The results showed that the latter two methods might be originally superior to the former in obtaining powdered inclusion completes. Especially, it was shown by powder X-ray diffractometry that spray-dried ${\beta}-CyD$ alone, TPA-spray-dried ${\beta}-CyD$ physical mixture, and spray-dried $TPA-{\beta}-CyD$ complex were amorphous. The dissolution behaviours of $TPA-{\beta}-CyD$ systems prepared by above four methods were compared with those of TPA alone and $TPA-{\beta}-CyD$ physical mixture, and the rates of dissolution of TPA in pH 1.2 buffer were greatly enhanced by inclusion complexation and copulverization.

• Textile Coloration and Finishing
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• v.29 no.2
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• pp.69-76
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• 2017

To get the proper treatment conditions, sulfonation reactions of persimmon tannin with sodium sulfite and sulfuric acid were proceeded in various settings, respectively. Also, the property changes were investigated by carrying out the additional analysis: elementary analysis and instrumental analysis using FT-IR, DSC, and TGA. The degree of $-SO_3Na$ substitutions appeared 0.216 and 0.208 under the treatment time of 3 hours and 6 hours, respectively and the degree of $-SO_3H$ substitutions indicated 0.200 and 0.167 under 9 hours and 18 hours, respectively by elemental analysis. In terms of the FT-IR spectras, there was a peak based on the bonds of pyran ring and ether in relation to non-treated and sulphonated tannin at $1,102cm^{-1}$. No peak was shown in the sulfited tannin. An absorption peak which was due to the $C{\rightarrow}O$ of secondary -OH group became evident in nontreated and sulfited tannin at $1,092cm^{-1}$ and $1,090cm^{-1}$, respectively but the same result was not found in sulphonated tannin. The results of TGA analysis of the sulfonated persimmon tannin showed that the sulfonation of it improved thermal properties.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.69-73
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• 2008

In this paper, analytical methods for calculating the average probability of bit error of time hopping pulse position modulation ultra wideband (TH-PPM UWB) system are given. For the multi-user DS-PAM UWB system, the bipolar pulse amplitude modulation is used in order to achieve better performance. As we know, more attention is paid to the TH-PPM UWB systems recently. In this paper, we first introduce the accurate BER calculation methods of the multi-user TH-PPM UWB systems and then give the performance analysis over the ideal AWGN channel and a correlation receiver. Furthermore, we also introduce their applications in image transmission and data transmission and give the simulation results. The analytical method yields simple and exact formulas relating the performance to the system parameters.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.908-925
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• 2014

Induction Motor (IM) has several desirable features for high performance adjustablespeed operation. This paper presents the design of a robust controller for vector control induction motor drive performances improvement. Proposed predictive speed controller, which is aimed to guarantee the stability of the closed loop, is based on the Poisson-Laguerre (PL) models for the association vector control drive and the induction motor; without necessity of any mechanical parameter, and requires only two control parameters to ensure implicitly the integrator effect on the steady state error, load torque disturbances rejection and anti-windup effect. In order to improve robustness, insensitivity against external disturbances and preserve desired performance, adaptive control is added with the aim to ensure an online identification of controller parameters through an online PL models identification. The proposed control is compared with the conventional approach using PI controller. Simulation with MATLAB/SIMULINK software and experimental results for a 1kW induction motor using a dSPACE system with DS1104 controller board are carried out to show the improvement performance.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.27-33
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• 2005

The shape memory effect in Ti-50.4at.%Ni alloy after solution treatment at 1273K for 2h and aged at 350, 450, $550^{\circ}C$ for 0.5, 1, 1.5, 2, 4, 10hrs had been investigated by differential scanning calorimetry measurement. It was found that ageing in the temperature range of $350^{\circ}C{\sim}550^{\cric}C$ induced complex transformation behavior, involving the R-phase and multiple-stage martensitic transformation. Usually aged Ni-rich NiTi alloys undergo martensitic transformation on cooling from high temperatures in two step : Austenite to R-phase and then R-phase to Martensite (normal behavior). In sample aged at $350^{\circ}C$ two distinct DSC peaks arised giving evidence of intermediate stages of martensite transformation. This results in the nucleation and growth of coherent $Ni_4Ti_3$-precipitate. These explain all features of the evolution of DSC charts during ageing including the number of distinct DS peaks and their positions.