• Title/Summary/Keyword: gain adaptation

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A Grounded Theory Approach on Peoples' Adaptation Experience with Fibromyalgia Syndrome (섬유근통증후군 환자의 질병 적응경험에 관한 근거이론 연구)

  • Jeong, Chu-Yeong;Kim, Myung-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.12
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    • pp.381-393
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    • 2016
  • This was a qualitative study to explore and better understand the adaptation experience and processes of peoples with fibromyalgia syndrome (FMS), as well as to develop a substantive theory using the grounded theory method. There were 13 patients (12 females and 1 male) who received FMS treatment from Rheumatic Medicine outpatient department of one general hospital. The data were collected through an in-depth interview between January and May of 2014. Transcribed interview contents were analyzed by the grounded theory method of Corbin and Strauss (2008). As a result, a total of 98 concepts, 26 sub-categories, and 10 categories were identified through the open coding process. The process of adaptation experience showed 4 steps: perception of uncertainty and limited condition, evaluation of self-control possibility and determinations of expectations of life, searching and trying of strategies, as well as self-regulation. The 4 types of adaptation experience were expansionary, complacently, effusively and withering. The 'protective self-regulation' theory was derived from the core category of 'learning to self-regulation method'. Patients with FMS has repeatedly attempted these strategies of protective self-regulation in order to gain stability from uncertainty and limited condition of the disease. Based on these results, it is necessary to develop an educational program for patients and families which has appropriate nursing intervention strategies in accordance with the types of adaptation.

Chromatic Adaptation Model for the Variations of the Chromaticity tinder the Surround Viewing Conditions (주위 시환경의 색도 변화에 따른 색 순응 모델)

  • Kim, Eun-Su;Jang, Soo-Wook;Lee, Sung-Hak;Sohng, Kyu-Ik
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.5 s.305
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    • pp.19-28
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    • 2005
  • Real surround viewing conditions in watching the color display devices such as TV and PC monitor are quite different from the standard viewing conditions. Human visual system is adapted chromatically under the different viewing conditions in luminance levels and chromaticity of illuminants. Accordingly, the reproduced colors of the same chromaticity will appear as quite different color. Therefore, it is necessary that the displayed colors are reproduced to be appeared as the original colors in the standard viewing conditions. In this paper, we propose a chromatic adaptation model for the variations of the surround illuminants' chromaticity under the same luminance conditions. In proposed chromatic adaptation model, we calculate each gain of L, M, and S as nonlinear functions according to the chromaticity of the surround illuminants. And the optimal coefficients are obtained from the corresponding colors data of the Breneman's experiments. The proposed chromatic adaptation model is compared with the conventional chromatic adaptation models. In the experimental results, the proposed model has very good performance in the whole range of luminance levels. We also experimentally confirmed that the reproduced corresponding colors using the proposed chromatic adaptation are appeared as the original colors when the real surround viewing conditions are different from the standard viewing conditions.

A Fast and Precise Blind I/Q Mismatch Compensation for Image Rejection in Direct-Conversion Receiver

  • Kim, Suna;Yoon, Dae-Young;Park, Hyung Chul;Yoon, Giwan;Lee, Sang-Gug
    • ETRI Journal
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    • v.36 no.1
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    • pp.12-21
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    • 2014
  • In this paper, we propose a new digital blind in-phase/quadrature-phase (I/Q) mismatch compensation technique for image rejection in a direct-conversion receiver (DCR). The proposed image-rejection circuit adopts DC offset cancellation and a sign-sign least mean squares (LMS) algorithm with a unique step size adaptation both for a fast and precise I/Q mismatch estimation. In addition, several performance-optimizing design considerations related to accuracy, speed, and hardware simplicity are discussed. The implementation of the proposed circuit in an FPGA results in an image-rejection ratio (IRR) of 65 dB, which is the best performance with modulated signals, along with an adaptation time of 0.9 seconds, which is a tenfold increase in the compensation speed as compared to previously reported circuits. The proposed technique will be a promising solution in the area of image rejection to increase both the speed and accuracy of future DCRs.

GOP Adaptation Coding of H.264/SVC Based on Precise Positions of Video Cuts

  • Liu, Yunpeng;Wang, Renfang;Xu, Huixia;Sun, Dechao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.7
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    • pp.2449-2463
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    • 2014
  • Hierarchical B-frame coding was introduced into H.264/SVC to provide temporal scalability and improve coding performance. A content analysis-based adaptive group of picture structure (AGS) can further improve the coding efficiency, but damages the inter-frame correlation and temporal scalability of hierarchical B-frame to different degrees. In this paper, we propose a group of pictures (GOP) adaptation coding method based on the positions of video cuts. First, the cut positions are accurately detected by the combination of motion coherence (MC) and mutual information (MI); then the GOP is adaptively and proportionately set by the analysis of MC in one scene. In addition, we propose a binary tree algorithm to achieve the temporal scalability of any size of GOP. The results for test sequences and real videos show that the proposed method reduces the bit rate by up to about 15%, achieves a performance gain of about 0.28-1.67 dB over a fixed GOP, and has the advantages of better transmission resilience and video summaries.

The Design of MRAC with Fuzzy Adaptation Law (퍼지 적응 법칙을 갖는 기준모델 적응제어기 설계)

  • Cho, Jong-Hoon;Kwon, Hyuk-Jin;Seo, Seung-Hyun;Moon, Dong-Uk;Nam, Moon-Hyon
    • Proceedings of the KIEE Conference
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    • 1995.07b
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    • pp.685-688
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    • 1995
  • In this paper we proposed new scheme replacing adaptive mechanism part in MRAC by fuzzy logic in order to improve transient response in adaptive control system. Conventional adaptive control system has good performance in steady state but it has large error or problem with rise time in transient state. We need to increase adaptation gain of control variable but it causes robustness problem that makes ststem unstable for set-point, load-variation, and dynamic change. To demonstrate presented FTAC(fuzzy tunning adaptive control)'s superiority, presented method is introduced for a class of SISO systems and compare with MRAC. By analyzing simulation result, we can see transient response is improved and the system is not affected by disturbance in proposed method in comparison to MRAC.

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Model Reference Adaptive Control for Multivariable Systems (다변수 시스템에 대한 기준 모델형 적응 제어)

  • Hai-Won Yang
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.32 no.11
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    • pp.394-403
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    • 1983
  • This paper discusses a model reference adaptive control for a multi-input multi-output continuos system in matrix fraction description. The controller is of Monopoli-Narendra type with a time-varying gain matrix in the parameter adaptation law. The transfer matrix of the given plant with an adjustable controller is made to approach to that of the reference model asymptotically. It is shown that, under some plausible assumptions such as on the knowlidge of an interactor matrix, the algorithm for a single-input single-output system can be appropriately extended to a multi-input multi-output system. The convergence of an adaptation law is estavlished with some stability theory and stability of the overall system is asserted by an analytical investigation.

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Recognition for Noisy Speech by a Nonstationary AR HMM with Gain Adaptation Under Unknown Noise (잡음하에서 이득 적응을 가지는 비정상상태 자기회귀 은닉 마코프 모델에 의한 오염된 음성을 위한 인식)

  • 이기용;서창우;이주헌
    • The Journal of the Acoustical Society of Korea
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    • v.21 no.1
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    • pp.11-18
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    • 2002
  • In this paper, a gain-adapted speech recognition method in noise is developed in the time domain. Noise is assumed to be colored. To cope with the notable nonstationary nature of speech signals such as fricative, glides, liquids, and transition region between phones, the nonstationary autoregressive (NAR) hidden Markov model (HMM) is used. The nonstationary AR process is represented by using polynomial functions with a linear combination of M known basis functions. When only noisy signals are available, the estimation problem of noise inevitably arises. By using multiple Kalman filters, the estimation of noise model and gain contour of speech is performed. Noise estimation of the proposed method can eliminate noise from noisy speech to get an enhanced speech signal. Compared to the conventional ARHMM with noise estimation, our proposed NAR-HMM with noise estimation improves the recognition performance about 2-3%.

Effects of dietary fermented spent coffee ground on nutrient digestibility and nitrogen utilization in sheep

  • Choi, Yongjun;Rim, Jong-su;Na, Youngjun;Lee, Sang Rak
    • Asian-Australasian Journal of Animal Sciences
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    • v.31 no.3
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    • pp.363-368
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    • 2018
  • Objective: The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Methods: Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum. Fermentation was performed at moisture content of 70% and temperature of $39^{\circ}C$ with anaerobic air tension for 48 h. Four adult rams (initial body weight = $56.8{\pm}0.4kg$) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in $4{\times}4$ Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. Results: In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p<0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Conclusion: Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed.

Color Reproduction in Television Receiver Based on Chromatic Adaptation of Human Visual System (시각계 색 순응을 고려한 텔레비전 수상기에서의 색 재현)

  • Choi, Duk-Kyu;Han, Chan-Ho;Lee, Kuhn-Il;Sohng, Kyu-Ik
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.11
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    • pp.133-143
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    • 1998
  • The viewers primarily watch a television under the surround light source of an incandescent or a fluorescent light. When human visual system has been adapted chromtically under the different surround light, the same chromaticities elicit quite different color appearnaces. Therefore, the corresponding color reproduction is the most suitable objective of a color television system. In this paper, an efficient corresponding color reproduction method based on the chromatic adaptation of human visual system is proposed in which colors in the display have the same appearance as the colors in the original would have had if they had been illuminated by standard illuminant ($D_{65}$). The chromaticities that appeared neutral in human visual system were determined by the Hunt's experimental results of the color adaptation in picture viewing situations and the corresponding chromaticity coordinates of stimuli in chromatic adaptation were obtained by the Bartleson's theory. Also, the corresponding color reproduction is realized by changing the phase and the gain of the demodulation axes in television receiver. Experimental results show that the proposed corresponding color displayed on the television is better than that of the conventional colorimetric color reproduction under the surround light sources.

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Robust Sensorless Sliding Mode Flux Observer for DTC-SVM-based Drive with Inverter Nonlinearity Compensation

  • Aimad, Ahriche;Madjid, Kidouche;Mekhilef, Saad
    • Journal of Power Electronics
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    • v.14 no.1
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    • pp.125-134
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    • 2014
  • This paper presents a robust and speed-sensorless stator flux estimation for induction motor direct torque control. The proposed observer is based on sliding mode approach. Stator electrical equations are used in the rotor orientation reference frame to eliminate the observer dependence on rotor speed. Lyapunov's concept for systems stability is adopted to confine the observer gain. Furthermore, the sensitivity of the observer to parameter mismatch is recovered with an adaptation technique. The nonlinearities of the pulse width modulation voltage source inverter are estimated and compensated to enhance stability at low speeds. Therefore, a new method based on the model reference adaptive system is proposed. Simulation and experimental results are shown to verify the feasibility and effectiveness of the proposed algorithms.