• 한국의류학회지
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• 제26권1호
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• pp.83-94
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• 2002

This study was intended to identify fabric impact on decision-making process for clothing purchase, to determine evaluation factors of clothing, and to analyze consumer's preference for fabric on clothing purchase. 396 questionnaires distributed to college students were analyzed by descriptive statistics, oneway ANOVA, correlation, factor analysis and multidimensional scaling. The results are as follows; (1) Fabric impacted on the pre-purchase evaluation and the post-purchase process. (2) 4 factors - physical properties, outer-consciousness, self-satisfaction, and appropriateness- were determined as evaluation factors. Though fabric was included in the physical properties, fabric presented high correlations with other evaluative elements. (3) The most preferred fabric was being composed of natural fiber in fiber contents and having softness in sensation. As a result of multidimensional scaling, 2 dimensions of fabric sensation were developed as 'soft-hard'and 'thin-thick'.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.113-116
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• 2002

This paper describes a design of 8192-Point pipelined FFT/IFFT processor (PFFTSk) core for DVB-T and DMT-based VBSL modems. A novel two-step convergent block floating -point (75_CBFP) scaling method is proposed to improve the signal- to-quantization-noise ratio (SeNR) of FFT/IFFT results. Our approach reduces about 80% of memory when compared with conventional CBFP methods. The PFFTSk core, which is designed in VHDL and synthesized using 0.25-${\mu}{\textrm}{m}$ CMOS library, has about 76,300 gates, 390k bits RAM, and Twiddle factor ROM of 39k bits. Simulation results show that it can safely operate up to 50-MHz clock frequency at 2.5-V supply, resulting that a 8192-point FFT/IFFT can be computed every 164-$mutextrm{s}$. The SQNR of about 60-dB is achieved.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.295-297
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• 2007

We design a new rate-3/2 full-diversity orthogonal space-time block code (STBC) for QPSK and 2 transmit antennas (TX) and 4 transmit antennas (TX) by enlarging the signalling set from the set of quaternions used in the Alamouti[I] and extendedcode and using additional members of the set of orthogonal matrices or Quasi-orthogonal matrices and higher than rate-5/4. Selective power scaling of information symbols is used to guarantee full-diversity while maximizing the coding gain (CG) and minimizing the transmitted signal peak-to-minimum power ratio (PMPR). The optimum power scaling factor is derived analytically and shown to outpetform schemes based only on constellation rotation while still enjoying a low-complexity maximum likelihood (ML) decoding algorithm.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2009년도 춘계학술발표논문집
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• pp.307-310
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• 2009

임의의 입력 해상도와 출력 해상도의 비율로 주어지는 영상 축소 스케일러를 구현하려면 축소된 영상에 대한 화소의 좌표를 계산하기 위해서 범용 제산기의 사용이 요구된다. 이 범용 제산기는 매 화소마다 동작해야하기 때문에 처리속도를 높이기 위하여 LUT로 구현되나, LUT의 정밀도에 따라서 하드웨어의 규모가 비대해지는 문제가 야기된다. 본 논문에서는 제산기나 LUT 기반의 제산 연산을 수반하지 않는 영상 축소 알고리즘을 제안한다. 제안한 알고리즘은 비교기와 가산기 만으로 구성되어 있으며, 임의의 유리수로 표현되는 축소 비율을 허용함에도 불구하고, 기존 방식에 비해서 1/10 이하로 하드웨어 규모를 줄이는 것이 가능하다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.395-399
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• 2004

We present modality conversion as an effective means for QoS management. We show that modality conversion, in combination with content scaling, would give a wider range of adaptation to support QoS at media level. Here, we consider modality conversion with respect to resource constraint and human factor. To represent modality conversion as well as content scaling, we present the overlapped content value (OCV) model that relates the content value of different modalities with resources. The specification of user preference on modality conversion is divided into qualitative and quantitative levels. The user preference is then integrated into the OCV model so that modality conversion correctly reflects the user's wishes. For the conversion of multiple contents, an optimization problem is formulated and solved by dynamic programming. The experiments show that the proposed approach is efficient to be applied in practice.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.2545-2547
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• 2000

In this paper, a hybrid fuzzy controller using genetic algorithm based on parameter estimation mode to obtain optimal control parameter is presented. First, The control input for the system in the HFC is a convex combination of the FLC's output in transient state and PID's output in steady state by a fuzzy variable, namely, membership function of weighting coefficient. Second, genetic algorithms is presented to automatically improve the performance of hybrid fuzzy controller utilizing the conventional methods for finding PID parameters and estimation mode of scaling factor. The algorithms estimates automatically the optimal values of scaling factors, PID parameters and membership function parameters of fuzzy control rules according to the rate of change and limitation condition of control input. Computer simulations are conducted to evaluate the performance of proposed hybrid fuzzy controller. ITAE, overshoot and rising time are used as a performance index of controller.

• 정보처리학회논문지A
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• 제11A권3호
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• pp.173-180
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• 2004

계층적 자료구조인 사진트리는 영상을 표현하는데 매우 중요한 자료구조이다. 사진트리를 메모리에 저장하는 방법 중 선형 사진트리 표현방법은 다른 표현 방법과 비교할 때 저장 공간을 매우 효율적으로 절약할 수 있는 이점이 있기 때문에 사진트리와 관련된 연산의 수행을 위해 선형 사진트리를 사용하는 효율적인 알고리즘 개발에 많은 연구가 진행되어 왔다. 영역 확장은 영상을 주어진 거리만큼 확장시키는 연산이고, 스케일링은 영상을 주어진 크기만큼 증폭시키는 연산으로 영상의 기하학적 연산에 속한다. 본 논문에서는 RMESH(Reconfigulrable MESH) 구조에서 3-차원 n${\times}$n${\times}$n 프로세서를 사용하여 선형 사진트리로 표면된 영상의 영역 확장과 스케일링을 수행하는 효율적인 알고리즘을 제안한다. 이 알고리즘은 n${\times}$n${\times}$n RMESH의 계층구조에서 선형 사진트리의 위치코드들을 효율적으로 전송할 수 있는 기본적인 연산들을 이용함으로써 상수 시간의 시간복잡도를 갖는다.

• 대한전자공학회논문지SD
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• 제46권12호
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• pp.96-104
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• 2009

일반적인 동적 전압 조절(dynamic voltage scaling)의 가정과는 다르게 실제 시스템에 있어서는 응용 프로그램의 성능이 프로세서의 동작 속도에 정비례하지 않는다. 본 연구에서는 응용 프로그램의 성능과 동작 속도의 관계를 실측을 통하여 수치화하여 응용 프로그램의 특성을 모델링하고 각기 다른 응용 프로그램 특성 계수를 갖는 태스크 집합에 적합한 스케줄링 기법을 제시하였다. 또한, 모든 태스크의 단위 수행시간 변화에 따른 에너지의 변화량이 동일해야 에너지 최적이 된다는 해석적인 정리를 제시하였다. 본 연구에서 제시하는 스케줄링 기법은 이러한 해석적 정리에 기반을 두기 때문에 항상 각 태스크에 시스템 에너지 최적이 되는 조절비를 제시한다. 합성 태스크 집합을 이용한 실험결과에서 기존 연구 대비 약 7%의 추가적인 에너지 절감 효과를 얻을 수 있었다.

• 복식
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• 제54권3호
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• pp.73-85
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• 2004

The purpose of this study was to investigate the characteristic and sensibility of Japanism fashion designs which represented by Japanese designers and Western designers. The stimulus were 29 pictures of contemporary fashion designs which represented the Japanism style fashion designs from fashion collections. The data were analyzed by Cluster analysis, Factor analysis, Multidimensional Scaling Method and Regression Analysis. The specific objectives were as follows ; 1) As result of design analysis, Japanism fashion sensibility is unique and good-looking. 2) As result of the factor analysis. 4 factors which are Attractiveness, Attention, Maturity and Hardness and softness. 3) According to sensibility positioning, The Japanism fashion design was classified by Decorative-Simple, Hard-Soft. 4) As result of the Regression Analysis, The preference of Japanism fashion design was related to attractive factor. 5) As result of the Regression Analysis. The buying desirable of Japanism fashion design was related to attractive, attentive and mature factor.

• 산업기술연구
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• 제25권A호
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• pp.39-47
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• 2005

Air void systems in hardened concrete has an important influence on concrete durability such as freeze-thaw resistance, water permeability, surface scaling resistance. Linear traverse method and point count method described at ASTM are the routine analysis of the air void system that have been widely used to estimate the spacing factor in hardened concrete. Recently, many concretes often have a spacing factor higher than the generally accepted $200-250{\mu}m$ limit for the usual range of air contents. This study is proposed to estimate the plane spacing factor by calculation of simplicity. The plane spacing factor need two parameters that are air content and numbers of air voids in the hardened concrete. Those obtained from the standard air-void system analysis of the ASTM C 457. The equation is valid for all values of paste-to-air ratio because the estimation of paste content is unnecessary at the using ASTM C 457. The plane spacing factor yields a similar estimate of the standard spacing factor.