• Title/Summary/Keyword: I/f control

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Depression of L-type $Ca^{2+}$ and Transient Outward $K^+$ Currents in Endotoxin-treated Rat Cardiac

  • Park, Kyu-Sang;Lee, Boo-Soo;Kong, In-Deok;Lee, Joong-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.6
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    • pp.623-630
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    • 1999
  • Decreased cardiac contractility occurs in endotoxicosis, but little is known about the ionic mechanism responsible for myocardial dysfunction. In this study, we examined the changes in $Ca{2+}$ and $K^+$ currents in cardiac myocytes from endotoxin-treated rat. Ventricular myocytes were isolated from normal and endotoxemic rats (ex vivo), that were treated for 10 hours with Salmonella enteritidis lipopolysaccharides (LPS; 1.5 mg/kg) intravenously. Normal cardiac myocytes were also incubated for 6 hours with 200 ng/ml LPS (in vitro). L-type $Ca{2+}$ current $(I_{Ca,L})$ and transient outward $K^+$ current $(I_{to})$ were measured using whole cell patch clamp techniques. Peak $I_{Ca,L}$ was reduced in endotoxemic myocytes (ex vivo; 6.00.4 pA/pF, P<0.01) compared to normal myocytes (control; 10.90.6 pA/pF). Exposure to endotoxin in vitro also attenuated $I_{Ca,L}$ (8.40.4 pA/pF, P<0.01). The amplitude of $(I_{to})$ on depolarization to 60 mV was reduced in endotoxin treated myocytes (16.51.5 pA/pF, P<0.01, ex vivo; 20.00.9 pA/pF, P<0.01 , in vitro) compared to normal myocytes (control; 24.71.0 pA/pF). There was no voltage shift in steady-state inactivation of $I_{Ca,L}$ and $(I_{to})$ between groups. These results suggest that endotoxin reduces $Ca{2+}$ and $K^+$ currents of rat cardiac myocytes, which may lead to cardiac dysfunction.

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Optimal Tuning Strategy for 2-Degree-of-Freedom i-PID Controllers (2 자유도 지적 PID 제어기의 파라미터 설정)

  • Choe, Yeon-Wook
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.9
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    • pp.1202-1209
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    • 2018
  • This paper is concerned with the problem of setting controller's parameters when applying the intelligent PID (i-PID), which has recently been proposed and had many successful results, to the two-degree-of-freedom (2DoF) PID controller structure. Generally, the parameter settings of conventional PID controllers are known to be quite difficult and be dependent on the characteristics of the plants. In addition, it is less known how the two 2DoF parameters are set up for the improvement of transient characteristics. Here, we are going to present one of the criteria for parameter setting in the case of using a 2DoF i-PID, by evaluating the error signals to the set-point and disturbance. That is, we first, obtain parameters of i-PID by optimizing the disturbance responses, and then determine two parameters of 2DoF component through optimizing set-point response. The standard values of all parameters are calculated for the 7 types of test batches and rounded up as a table.

Characteristics of Speech Intelligibility and the Vowel Space in Patients with Parkinson's disease (파킨슨병 환자의 말 명료도와 모음 공간 특성)

  • Shim, Hee-Jeong;Park, Won-Kyoung;Ko, Do-Heung
    • Phonetics and Speech Sciences
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    • v.4 no.3
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    • pp.161-169
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    • 2012
  • The purpose of this study was to investigate the characteristics of speech intelligibility of spontaneous speech and the vowel space parameters in patients with Parkinson's disease. Ten PD patients (M=5, F=5) and a corresponding control group of ten normal adults participated in this study. Firstly, subjects were asked to tell a story about their hometown and youth in order to analyze speech intelligibility. Secondly, the subjects were also asked to repeat four vowels (/a/, /i/, /u/, /e/) five times in order to compare their vowel spaces. The results were as follows: (1) the speech intelligibility of the PD group was lower than that of the control group. (2) Four parameters including vowel area, vowel articulatory index, formant centralization ratio, F2i/F1u ratio were significantly different in each group. For instance, vowel area and F2 ratio were wider and higher, respectively. As a result, a decrease in speech intelligibility of patients with PD is likely to show different types of errors from the normal group. The results of this research are meaningful in a sense that they could provide the objective standard of speech intelligibility and vowel space parameters.

Implementation of a Speaker-independent Speech Recognizer Using the TMS320F28335 DSP (TMS320F28335 DSP를 이용한 화자독립 음성인식기 구현)

  • Chung, Ik-Joo
    • Journal of Industrial Technology
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    • v.29 no.A
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    • pp.95-100
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    • 2009
  • In this paper, we implemented a speaker-independent speech recognizer using the TMS320F28335 DSP which is optimized for control applications. For this implementation, we used a small-sized commercial DSP module and developed a peripheral board including a codec, signal conditioning circuits and I/O interfaces. The speech signal digitized by the TLV320AIC23 codec is analyzed based on MFCC feature extraction methed and recognized using the continuous-density HMM. Thanks to the internal SRAM and flash memory on the TMS320F28335 DSP, we did not need any external memory devices. The internal flash memory contains ADPCM data for voice response as well as HMM data. Since the TMS320F28335 DSP is optimized for control applications, the recognizer may play a good role in the voice-activated control areas in aspect that it can integrate speech recognition capability and inherent control functions into the single DSP.

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Effect of a Resident and Indoor Environmental Characteristics on the House Dust Mites Allergen (주거환경 특성에 따른 집먼지진드기 항원량에 관한 조사)

  • Kim, Yong-Soon;Park, Jee-Won;Song, Young-Shin
    • Research in Community and Public Health Nursing
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    • v.13 no.1
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    • pp.79-88
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    • 2002
  • Purpose: The purpose of this study was to identify the indoor environment i.e. house type and age, ventilation method, use of bed & sofa, cockroach, ants, etc. on HDM (House dust mites), especially Der fI allergen. Method: Samples of dust from mattresses, pillows and the floor were collected by using a vacuum cleaner from April. 2000. The amount of Group I allergen(Der. fI) of HDM (house dust mites) were measured by two-site ELISA. Indoor Environmental characteristics were accessed by using questionnaires on 178 house wives living in the Seoul area. Results: The amount of HDM allergen (Der fI) was higher in sofa using house. There were higher concentrations of HDM allergen (Der fI) in sofas made from quilt material than for those that were made from leather. Homes that had pets like dogs living in them had higher concentrations of HDM allergen (Der fI) than without dogs. Conclusion: The photophobic mites thrive in dark. warm and humid environments; Items such as pillows. mattresses, box springs, blankets. carpets. and upholstered furniture should be considered ideal environments for the mite. Therefore, an indoor environmental control program should be carried out to avoid the HDM allergen.

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Design of a 16 bit Motion Controller Using dsPIC30F2010 (dsPIC30F2010을 이용하는 16비트급 모션제어기 설계)

  • Park, Jun-ho;Min, Bung-kil;Kunn, Young;Kang, Tae-jong;Choi, Jung-keyng
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.841-844
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    • 2013
  • This paper suggests methods to drive motor and dsPIC30F2010 microprocessor software design for the Wheel Hub Motor that is incorporated into a hub of the wheel and drives it directly. The minimum function of dsPIC30F2010, system clock, PWM, I/O, communication, applicable to hub motor control are explained and tested. The algorithm including PI control method was implemented to the system by using dsPIC30F2010 microprocessor functions.

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Sensorless Transition Algorithm of PM Synchronous Motor by Load Torque Estimation (영구자석동기전동기의 부하추정을 통한 센서리스 전환 알고리즘)

  • Kim, Dong-Hyun;Cho, Kwan-Yuhl;Kim, Hag-Wone
    • The Transactions of the Korean Institute of Power Electronics
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    • v.26 no.5
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    • pp.349-356
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    • 2021
  • Permanent magnet synchronous motors are mainly used in the traction of electric vehicle and home application products including air-conditioners and refrigerators. For sensorless control without rotor position sensors, I-F control is applied for initial starting at low speeds, and mode is changed to sensorless control when the rotor speed is sufficiently accelerated for estimating rotor position. When the mode is changed to the sensorless control from the open-loop starting, the initial integral value of the speed controller should be considered by load condition; otherwise, the transition to sensorless control may fail. The sensorless transfer algorithm of PM synchronous motor based on load condition for smooth transition is proposed. The performance of the proposed sensorless transfer algorithm was verified by experiments.

A Vector-Controlled PMSM Drive with a Continually On-Line Learning Hybrid Neural-Network Model-Following Speed Controller

  • EI-Sousy Fayez F. M.
    • Journal of Power Electronics
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    • v.5 no.2
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    • pp.129-141
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    • 2005
  • A high-performance robust hybrid speed controller for a permanent-magnet synchronous motor (PMSM) drive with an on-line trained neural-network model-following controller (NNMFC) is proposed. The robust hybrid controller is a two-degrees-of-freedom (2DOF) integral plus proportional & rate feedback (I-PD) with neural-network model-following (NNMF) speed controller (2DOF I-PD NNMFC). The robust controller combines the merits of the 2DOF I-PD controller and the NNMF controller to regulate the speed of a PMSM drive. First, a systematic mathematical procedure is derived to calculate the parameters of the synchronous d-q axes PI current controllers and the 2DOF I-PD speed controller according to the required specifications for the PMSM drive system. Then, the resulting closed loop transfer function of the PMSM drive system including the current control loop is used as the reference model. In addition to the 200F I-PD controller, a neural-network model-following controller whose weights are trained on-line is designed to realize high dynamic performance in disturbance rejection and tracking characteristics. According to the model-following error between the outputs of the reference model and the PMSM drive system, the NNMFC generates an adaptive control signal which is added to the 2DOF I-PD speed controller output to attain robust model-following characteristics under different operating conditions regardless of parameter variations and load disturbances. A computer simulation is developed to demonstrate the effectiveness of the proposed 200F I-PD NNMF controller. The results confirm that the proposed 2DOF I-PO NNMF speed controller produces rapid, robust performance and accurate response to the reference model regardless of load disturbances or PMSM parameter variations.

The Design of a Control & Measurement System for the Driving of Wheel-in Motor (휠인 모터 구동을 위한 제어 및 계측 시스템 설계)

  • Choi, Jung-Keyng
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.4
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    • pp.405-411
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    • 2015
  • This paper sugg ests speed measurement and control system desig n methods to drive the Wheel-in Motor that is transfer rotational force to the hub of the wheel and drives it directly. The dsPIC30F2010 16 bit microprocessor specified to motion controller is used as a intelligent controller. The minimum functions of dsPIC30F2010, system clock, PWM output, I/O, timer, communication, applicable to motor control are used and operating characteristics of hall signal measurement and control software functions are tested. Also the algorithm including PDFF speed control program was implemented using this software functions and show the experimental results..

Experimental Study on the Effect of Hyperbaric Oxygen Therapy on the Ischemic Wound Healing of Rats. (고압산소요법이 백서 구강내외 허혈성 연조직 창상치유에 미치는 영향에 관한 실험적 연구)

  • Park, Chang-Joon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.11 no.1
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    • pp.153-170
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    • 1989
  • Recently, frequently using hyperbaric oxygen therapy is known for its effectiveness on the healing of problem wounds such as osteomyelitis, osteoradionecrosis and gas gangrenous wound etc. The main objectives of this study was to determine the best protocol of its application of hyperbaric oxygen therapy. Author used 238 rats (Sprague-Dawley strain) deviding into 2 Groups, experimental I group for skin and experimental II group for palatal mucosal ischemic wounds, and observed its effects by microscopically. The obtained results summarized as follows; 1. Severe infiltration of inflammatory cells was observed in initial stages of both control and experimental I group. The infiltration showed decreasing tendency at 5th day of experimental D, E, F group while at 8th day in control group In d, f of experimental II group showed decreasing tendency at 8th experimental day while at 12th day in control group. 2. Macrophages appeared at 2nd day in D of experimental I group while at 6th day in control group. In d, f of experimental II group appeared at 6th day while at 10th day in control group. 3. As to the proliferation of capillary blood vessels showed at 3-4 day in most of experimental I group severely while at 8th day in control group. In experimental II group, it was at 8th day and 12th day respectively. 4. The proliferation of fibroblasts showed rather rapider in experimental I group, at 4-6th day, while at 8th day in control group. In experimental II group, it was at 8th day and 12th day respectively. 5. As to the collagen formations, it was at 4th day in experimental I group while at 8th day in control group. In experimental II group, it was at 6th day and 10th day respectively. 6. 5 rats (2.0 %) in E group and 8 rats (3.4 %) in f group showed oxygen toxic reaction, such as unstable attitude and tremor, during the experiments. This hyperbaric oxygen animal experiments disclosed excellent effects on the ischemic wound healing and it is thought to be the best protocol of its application was on D group (2.5 ATM. and 2 hrs, exposure).

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