• Title/Summary/Keyword: fir

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A Study on Performance Improvement of Modified Window Function (변형된 창함수의 성능향상에 관한 연구)

  • Lee, Kyung-Hyo;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.925-928
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    • 2008
  • With basis of the development of information communication techniques in recent year, the digital processing techniquy also has been growed fast. The digital processing technique have used signals - speech and image processing- for processing of transmission and analysis. After we get and save the signals. Effective signal processing techniques have varied filters and typical digital filters are FIR filter and IIR filter. The FIR digital filter is more secure because phase response characteristics have linear phase. But, FIR digital filters have a problem to product the Gibbs phenomenon generating around a discontinuous point. A propose of filer is to remove the problem. Therefore, in this paper I was proposed a method using FIR digital filter applied a modified window function and the method was compared with conventional methods.

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A Design Method of Linear Phase FIR filters with MAXFLAT and MAXSHCUT frequency characteristics (MAXFLAT와 MAXSHCUT 주파수 특성을 갖는 선형 위상 FIR 필터 설계)

  • Jeon, Joon-Hyeon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.3
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    • pp.105-112
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    • 2007
  • In general, the earlier methods for the design of MAXFLAT FIR filters have existent problems due to the approximation algorithms used to approach MAXFLAT(maximally flat) response in the passband and the stopband.. The proposed approach advanced by using of MAXSHCUT(maximally sharp cutoff) condition in this paper clearly overcomes these problems. In this approach, we use a key parameter represented with filter-order and cutoff-frequency parameters for obtaining the lowpass filters with the MAXFLAT and MAXSHCUT characteristics in the frequency domain. Consequently, this design technique leads to new MAXFLAT and MAXSHCUT FIR digital filter, which can achieve sharp-cutoff responses with the stopband attenuation exceeding 100 dB almost everywhere.

Studies on the High-Temperature Drying Characteristics of Douglas-fir, Hemlock and Radiata Pine Square Timber (Douglas-fir, Hemlock, Radiata pine 정각재의 고온건조 특성에 관한 연구)

  • Lee, Chang-Jin;Lee, Nam-Ho;Oh, Seung-Won
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.5
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    • pp.726-735
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    • 2016
  • This study was carried out to evaluate the high-temperature drying characteristics of douglas-fir, hemlock, and radiata pine square timber with dimensions of thickness 15 cm and 18 cm. As a result, radiata pine showed the lowest final moisture content followed by douglas-fir and hemlock without reference to the timber size. Moreover, when the longitudinal kerfing is processed, the final moisture content was lower than control. The kerfing treatment was effective to decreasing the twist of radiata pine and hemlock. When douglas-fir is processed to the shape like the edge-grained timber that does not include the pith, the decrease of drying defect was possible.

Design of Circular Symmetric Two-Dimensional FIR Digital Filter (환상대칭 2차원FIR 디지털필터의 설계)

  • 이경철;강철호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.11 no.5
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    • pp.340-348
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    • 1986
  • The design of two-dimensional zero-phase FIR digital filters by transformations is a popular and well-developed technique, but is suffers from the disadvantage that in its current form the filters with only four quadrant symmetry can not be designed exactly circular symmetry at frequencies far from the origin. it is shown how symmetry requirement for the filters with any number of dimensions can be fulfilled with arbbitrary percision by adapting transformation with the appropriate series expansions. this transformation has been known generally as the McClellan transformation. In this paper, a simple method for ensuring exelent circular symmetry at frequencies far from the origin is presented. This method which employs the Modified Mcclellan trnsformation for the design of 2-D FIR filter form 1-D FIR filters is quite useful for the design of 2-D FIR filters with multiple cutoff boundaries such as band-pass filters.

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Emission of Far-infrared Ray in Packaging Paper

  • Lee, Ji-Young;Kim, Chul-Hwan;Jung, Ho-Gyeong;Shin, Tae-Gi;Seo, Jeong-Min;Lee, Young-Rok
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.40 no.5
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    • pp.47-52
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    • 2008
  • The far-infrared ray (FIR) has been applied to various fields such as medical therapy, kitchen utensils, bath supplies, and so on. The FIR-emitting agent was used to make functional paperboards to have freshness-maintaining ability. The FIR-emitting agent was diluted with different concentrations at 0.5% starch solution, and the FIR-emitting solutions were coated on paperboards, i.e., liner. The more the concentration of the FIR radiating agent increased at 0.5% cationic starch solution, the higher FIR emissivity and emission power of paperboards increased. The corrugated boxes made of paperboards coated by the FIR-radiating agents at over 5% dilution concentration endowed mandarin oranges in the boxes with greater antimicrobial activity than those in boxes made of paperboards coated by the agent at below 5% concentration. In addition, it was ascertained that treatment of the FIR agents rarely affected strength properties of paperboards.

A Design of Current-Mode Analog FIR Filter for Wireless Home Network (주파수가변형 무선PAN단말을 위한 전류모드 아날로그 FIR 필터의 설계)

  • Kim, Seong-Kweon;Kim, Kwang-Ho;Cho, Ju-Phil;Cha, Jae-Sang
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.10
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    • pp.35-40
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    • 2006
  • In this paper, a current-mode analog variable finite-impulse-response (FIR) filter with variable tap coefficient circuits is proposed for frequency selective wireless personal area network(WPAN) system or terminals. From the circuit simulation the operation of the 7-tap FIR filter is confirmed. The 0.0625-step tap coefficient circuit is designed and fabricated with $0.8[{\mu}m]$ CMOS technology. The proposed FIR filter has a variable length of taps and variable coefficients, so it has a potential for being used to frequency selective WPAN system or frequency selective wireless communication terminals.

Far-infrared Study of Supernova Remnants in the Large Megellanic Cloud

  • Kim, Yesol;Koo, Bon-Chul;Seok, Ji Yeon
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.53-53
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    • 2013
  • We present preliminary results of far-infrared(FIR) study of the supernova remnant(SNR)s in the Large Magellanic Cloud using the Herschel HERITAGE (HERschel Inventory of The Agents of Galaxy Evolution) data set. HERITAGE provides FIR data covering the entire LMC at 100,160, 250, 350, and 500 um. In order to confirm FIR emission associated with SNRs, we refer to Magellanic Cloud Emission-Line Survey (MCELS) H-alpha & SII data, Spitzer surveying the Agents of a Galaxy's Evolution (SAGE) Multiband Imaging Photometer (MIPS) 24um & 70um data, Chandra Supernova Remnants Catalog, and ATCA 4.8GHz continuum images of Dickel et al. (2005). Among 47 SNRs in the LMC, 7 SNRs show associated FIR emission. We present multi-wavelength view of 5 SNRs; DEM L249, N49, N63A, N132D, and the SNR in N4. N49 and N132D show morphological correlation in FIR and X-ray, suggesting that the FIR emission is from dust grains collisionally heated by X-ray emitting plasma. The FIR emission of N63A resembles H-alpha emission, which implies that the FIR line radiation could be dominant. The FIR images of the rest two objects, DEM L249 and SNR in N4, show no correlation to the other-waveband images.

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FIR Fixed-Interval Smoothing Filter for Discrete Nonlinear System with Modeling Uncertainty and Its Application to DR/GPS Integrated Navigation System (모델링 불확실성을 갖는 이산구조 비선형 시스템을 위한 유한 임펄스 응답 고정구간 스무딩 필터 및 DR/GPS 결합항법 시스템에 적용)

  • Cho, Seong Yun;Kim, Kyong-Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.5
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    • pp.481-487
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    • 2013
  • This paper presents an FIR (Finite Impulse Response) fixed-interval smoothing filter for fast and exact estimating state variables of a discrete nonlinear system with modeling uncertainty. Conventional IIR (Infinite Impulse Response) filter and smoothing filter can estimate state variables of a system with an exact model when the system is observable. When there is an uncertainty in the system model, however, conventional IIR filter and smoothing filter may cause large errors because the filters cannot estimate the state variables corresponding to the uncertain model exactly. To solve this problem, FIR filters that have fast estimation properties and have robustness to the modeling uncertainty have been developed. However, there is time-delay estimation phenomenon in the FIR filter. The FIR smoothing filter proposed in this paper makes up for the drawbacks of the IIR filter, IIR smoothing filter, and FIR filter. Therefore, the FIR smoothing filter has good estimation performance irrespective of modeling uncertainty. The proposed FIR smoothing filter is applied to the integrated navigation system composed of a magnetic compass based DR (Dead Reckoning) and a GPS (Global Positioning System) receiver. Even when the magnetic compass error that changes largely as the surrounding magnetic field is modeled as a random constant, it is shown that the FIR smoothing filter can estimate the varying magnetic compass error fast and exactly with simulation results.

A Study on 2-D FIR Filter Using the Bernstein Polynomial (Bernstein 다항식을 이용한 2-D FIR 필터에 관한 연구)

  • Seo, Hyun-Soo;Kang, Kyung-Duck;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.443-446
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    • 2005
  • As modern society needs to process of acquisition, storage and transmission of much information, the importance of signal processing is increasing and various digital filters are used in the two-dimensional signal such as image. And kinds of these digital filters are IIR(infinite impulse response) filter and FIR(finite impulse response) filter. And FIR filter which has the phase linearity, the easiness of creation and stability is applied to many fields. In design of this FIR filter, flatness property is a important factor in pass-band and stop-band. In this paper, we designed a 2-D Circular FIR filter using the Bernstein polynomial, it is presented flatness property in pass-band and stop-band. And we simulated the designed filter with noisy test image and compared the results with existing methods.

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A Study on the Determination of a Broadband FIR Beamformer Parameter (광대역 FIR 빔형성기 파라미터 결정에 관한 연구)

  • Choi Youngchol;Kim Seung-Geun;Kim Sea-Moon;Park Jong-Won;Lim Yong-Gon
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2004.05a
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    • pp.386-389
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    • 2004
  • Beamforming for underwater acoustic communication is affected by the broadband feature of underwater acoustic communication signal, which has the low center frequency compared to the signal bandwidth. In this paper, the baseband equivalent array signal model is derived and we present computer simulation results for the broadband finite impulse response (FIR) beamformer performance according to the FIR filter order and the tap spacing. If the FIR filter order is increased above the optimum value, the beamformer performance is degraded. Also the tap spacing is related to the optimum FIR filter order.

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