• Title/Summary/Keyword: fixed gain

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Intelligent Tuning Of a PID Controller Using Immune Algorithm (면역 알고리즘을 이용한 PID 제어기의 지능 튜닝)

  • Kim, Dong-Hwa
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.1
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    • pp.8-17
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    • 2002
  • This paper suggests that the immune algorithm can effectively be used in tuning of a PID controller. The artificial immune network always has a new parallel decentralized processing mechanism for various situations, since antibodies communicate to each other among different species of antibodies/B-cells through the stimulation and suppression chains among antibodies that form a large-scaled network. In addition to that, the structure of the network is not fixed, but varies continuously. That is, the artificial immune network flexibly self-organizes according to dynamic changes of external environment (meta-dynamics function). However, up to the present time, models based on the conventional crisp approach have been used to describe dynamic model relationship between antibody and antigen. Therefore, there are some problems with a less flexible result to the external behavior. On the other hand, a number of tuning technologies have been considered for the tuning of a PID controller. As a less common method, the fuzzy and neural network or its combined techniques are applied. However, in the case of the latter, yet, it is not applied in the practical field, in the former, a higher experience and technology is required during tuning procedure. In addition to that, tuning performance cannot be guaranteed with regards to a plant with non-linear characteristics or many kinds of disturbances. Along with these, this paper used immune algorithm in order that a PID controller can be more adaptable controlled against the external condition, including moise or disturbance of plant. Parameters P, I, D encoded in antibody randomly are allocated during selection processes to obtain an optimal gain required for plant. The result of study shows the artificial immune can effectively be used to tune, since it can more fit modes or parameters of the PID controller than that of the conventional tuning methods.

New Video Compression Method based on Low-complexity Interpolation Filter-bank (저 복잡도 보간 필터 뱅크 기반의 새로운 비디오 압축 방법)

  • Nam, Jung-Hak;Jo, Hyun-Ho;Sim, Dong-Gyu;Choi, Byeong-Doo;Cho, Dae-Sung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.5
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    • pp.165-174
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    • 2010
  • The H.264/AVC standard obtained better performance than previous compression standards, but it also increased the computational complexity of CODEC simultaneously. Various techniques recently included at the KTA software developed by VCEG also were increasing its complexity. Especially adaptive interpolation filter has more complexity than two times due to development for coding efficiency. In this paper, we propose low-complexity filter bank to improve speed up of decoding and coding gain. We consists of filter bank of a fixed-simple filter for low-complexity and adaptive interpolation filter for high coding efficiency. Then we compensated using optimal filter at each macroblock-level or frame-level. Experimental results shows a similar coding efficiency compared to existing adaptive interpolation filter and decoding speed of approximately 12% of the entire decoder gained.

An Incremental Multi Partition Averaging Algorithm Based on Memory Based Reasoning (메모리 기반 추론 기법에 기반한 점진적 다분할평균 알고리즘)

  • Yih, Hyeong-Il
    • Journal of IKEEE
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    • v.12 no.1
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    • pp.65-74
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    • 2008
  • One of the popular methods used for pattern classification is the MBR (Memory-Based Reasoning) algorithm. Since it simply computes distances between a test pattern and training patterns or hyperplanes stored in memory, and then assigns the class of the nearest training pattern, it is notorious for memory usage and can't learn additional information from new data. In order to overcome this problem, we propose an incremental learning algorithm (iMPA). iMPA divides the entire pattern space into fixed number partitions, and generates representatives from each partition. Also, due to the fact that it can not learn additional information from new data, we present iMPA which can learn additional information from new data and not require access to the original data, used to train. Proposed methods have been successfully shown to exhibit comparable performance to k-NN with a lot less number of patterns and better result than EACH system which implements the NGE theory using benchmark data sets from UCI Machine Learning Repository.

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Rate Allocation for Block-based Compressive Sensing (블록기반 압축센싱을 위한 율 할당 방법)

  • Nguyen, Quang Hong;Dinh, Khanh Quoc;Nguyena, Viet Anh;Trinh, Chien Van;Park, Younghyeon;Jeon, Byeungwoo
    • Journal of Broadcast Engineering
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    • v.20 no.3
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    • pp.398-407
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    • 2015
  • Compressive sensing (CS) has drawn much interest as a novel sampling technique that enables sparse signal to be sampled under the Nyquitst/Shannon rate. By noting that the block-based CS can still keep spatial correlation in measurement domain, this paper proposes to adapt sampling rate of each block in frame according to its characteristic defined by edge information. Specifically, those blocks containing more edges are assigned more measurements utilizing block-wise correlation in measurement domain without knowledge about full sampling frame. For natural image, the proposed adaptive rate allocation shows considerable improvement compared with fixed subrate block-based CS in both terms of objective (up to 3.29 dB gain) and subjective qualities.

Fuzzy PD plus I Controller of a CSTR for Temperature Control

  • Lee, Joo-Yeon;So, Hye-Rim;Lee, Yun-Hyung;Oh, Sea-June;Jin, Gang-Gyoo;So, Myung-Ok
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.5
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    • pp.563-569
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    • 2015
  • A chemical reaction occurring in CSTR (Continuous Stirred Tank Reactor) is significantly affected by the concentration, temperature, pressure, and reacting time of materials, and thus it has strong nonlinear and time-varying characteristics. Also, when an existing linear PID controller with fixed gain is used, the performance could deteriorate or could be unstable if the system parameters change due to the change in the operating point of CSTR. In this study, a technique for the design of a fuzzy PD plus I controller was proposed for the temperature control of a CSTR process. In the fuzzy PD plus I controller, a linear integral controller was added to a fuzzy PD controller in parallel, and the steady-state performance could be improved based on this. For the fuzzy membership function, a Gaussian type was used; for the fuzzy inference, the Max-Min method of Mamdani was used; and for the defuzzification, the center of gravity method was used. In addition, the saturation state of the actuator was also considered during controller design. The validity of the proposed method was examined by comparing the set-point tracking performance and the robustness to the parameter change with those of an adaptive controller and a nonlinear proportional-integral-differential controller.

Comparative Evaluation of Cotton Seed Meal and Sunflower Seed Meal in Urea Molasses Blocks Versus Commercial Concentrate as Supplement to Basal Ration of Wheat Straw with Stall-fed Buffalo Calves

  • Mirza, I.H.;Anjum, M.I.;Khan, A.G.;Azim, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.2
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    • pp.193-198
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    • 2004
  • Eighteen water buffalo calves of Nili-Ravi breed (about 15 months age and of $147{\pm}12$ kg average body weight and mixed sex) were used with six animals on each treatment. All the animals were fed long wheat straw for ad libitum intake as the basal ration. Animals in group-I were supplemented with ad libitum amount of urea molasses block having cotton seed meal (CSMB) while the animals in group-II were supplemented with ad libitum urea molasses block containing sunflower seed meal (SFMB) and group III animals were supplemented with a fixed amount of commercial concentrate feed (CCF). The experiment lasted for a period of 80 days (April to June). Results revealed a significantly decreased total feed intake (wheat straw+supplements) in group-III ($1,666{\pm}52$ g/h/d) as compared to group I ($2,299{\pm}194$ g/h/d) and group-II ($2,193{\pm}230$ g/h/d). Average daily supplement intakes were $891{\pm}87$; $666{\pm}104$ and $593{\pm}0$ grams per head in group I, II and III, respectively. Supplement intakes among groups were different (p<0.05). Average daily body weight gains (g/h) were $214{\pm}25$, $174{\pm}23 $and $183{\pm}24$ for group I, II and III, respectively. Feed conversion ratio (FCR) was found to be $10.74{\pm}1.12$, $12.60{\pm}0.88$ and $9.90{\pm}1.33$ grams for group No. I, II and III, respectively. The economic net benefit of live weight gain of calves were 7.63, 6.11 and 7.33 rupees/h/d for group No. I, II and III, respectively. Thus SFM can replace CSM and urea molasses blocks can replace commercial concentrates as supplement to basal ration of wheat straw.

Variation in the number of nucleoli and incomplete homogenization of 18S ribosomal DNA sequences in leaf cells of the cultivated Oriental ginseng (Panax ginseng Meyer)

  • Chelomina, Galina N.;Rozhkovan, Konstantin V.;Voronova, Anastasia N.;Burundukova, Olga L.;Muzarok, Tamara I.;Zhuravlev, Yuri N.
    • Journal of Ginseng Research
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    • v.40 no.2
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    • pp.176-184
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    • 2016
  • Background: Wild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation. Methods: The roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined. Results: In mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440-640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species. Conclusion: This study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine.

Design of Inductive Loaded Microstrip Patch Antennas with Suppressed Radiations along Horizontal Directions (수평방향 방사가 억제된 Inductive loaded 마이크로스트립 패치 안테나의 설계)

  • Yoon, Young-Min;Kwak, Eun-Hyuk;Kim, Boo-Gyoun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.2
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    • pp.56-66
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    • 2012
  • The inductive loaded patch antenna with suppressed radiation along the horizontal plane and enhanced broadside gain is investigated by adjusting the width and the via radius of a unit cell at a fixed length of a unit cell. The effects of the via radius and the width of the unit cell on the dispersion characteristics of the inductive loaded transmission line are investigated. The systematic study to determine the via radius and the width of the unit cell for the effective dielectric constant of the inductive loaded patch antenna close to 1 in order to suppress the radiation along the horizontal plane is presented. Inductive loaded patch antennas composed of five unit cells with resonant frequency of 5 GHz are designed and their radiation characteristics are presented. The horizontal radiation along the E-plane is greatly suppressed to less than -15 dBi when the effective dielectric constant of the inductive loaded patch antenna is slightly less than 1.

Design of Multiband Repeater Antenna with Fire-Fighting Band for In-Building Mobile Communication (소방무선대역을 포함하는 인빌딩용 다중대역 중계기 안테나 설계)

  • Kim, Sung-Min;Min, Kyeong-Sik
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.6
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    • pp.495-503
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    • 2016
  • This paper proposes the design of multiband repeater antenna with fire-fighting band for in-building mobile communication. The proposed antenna is composed of a center monopole and 4 parasitic elements on a circular plate. In order to realize good reflection coefficients at the multiband, mutual coupling between 4 parasitic elements and center monopole antenna is considered. The important parameters such as distance between parasitic element and a center monopole, and each height of a center monopole and 4 parasitic elements are simulated to obtain good antenna characteristics at the multiband. The diameter of 4 parasitic elements and a center monopole was fixed to 10 mm for easy design and manufacturing. The measurement results of reflection coefficients, 2-D patterns and gain agreed well with their simulation ones.

Genetic Parameters for Linear Type Traits and Milk, Fat, and Protein Production in Holstein Cows in Brazil

  • Campos, Rafael Viegas;Cobuci, Jaime Araujo;Kern, Elisandra Lurdes;Costa, Claudio Napolis;McManus, Concepta Margaret
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.476-484
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    • 2015
  • The objective of this study was to estimate genetic and phenotypic parameters for linear type traits, as well as milk yield (MY), fat yield (FY) and protein yield (PY) in 18,831 Holstein cows reared in 495 herds in Brazil. Restricted maximum likelihood with a bivariate model was used for estimation genetic parameters, including fixed effects of herd-year of classification, period of classification, classifier and stage of lactation for linear type traits and herd-year of calving, season of calving and lactation order effects for production traits. The age of cow at calving was fitted as a covariate (with linear and quadratic terms), common to both models. Heritability estimates varied from 0.09 to 0.38 for linear type traits and from 0.17 to 0.24 for production traits, indicating sufficient genetic variability to achieve genetic gain through selection. In general, estimates of genetic correlations between type and production traits were low, except for udder texture and angularity that showed positive genetic correlations (>0.29) with MY, FY, and PY. Udder depth had the highest negative genetic correlation (-0.30) with production traits. Selection for final score, commonly used by farmers as a practical selection tool to improve type traits, does not lead to significant improvements in production traits, thus the use of selection indices that consider both sets of traits (production and type) seems to be the most adequate to carry out genetic selection of animals in the Brazilian herd.