• Title/Summary/Keyword: simultaneous control

검색결과 942건 처리시간 0.04초

EIT Image Reconstruction by Simultaneous Perturbation Method

  • Kim, Ho-Chan;Boo, Chang-Jin;Lee, Yoon-Joon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.159-164
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    • 2004
  • In electrical impedance tomography (EIT), various image reconstruction algorithms have been used in order to compute the internal resistivity distribution of the unknown object with its electric potential data at the boundary. Mathematically the EIT image reconstruction algorithm is a nonlinear ill-posed inverse problem. This paper presents a simultaneous perturbation method as an image reconstruction algorithm for the solution of the static EIT inverse problem. Computer simulations with the 32 channels synthetic data show that the spatial resolution of reconstructed images by the proposed scheme is improved as compared to that of the mNR algorithm at the expense of increased computational burden.

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NC 선반에서 동시 3축을 이용한 구면 렌즈 가공 연구 (A Study on the Spherical Lens Manufacturing by Simultaneous 3-Axis for NC Lathe)

  • 이민기;이응석;안동율
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.956-961
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    • 2004
  • This paper proposes a study on the spherical lens manufacturing by simultaneous 3 axis for NC lathe. We use friction drive system for moving system in experimental diamond turing machine. The diamond turning machine use manufacturing for high quality lens, mirror and many optics products. Especially, the high tech industry require a lot of lens. For example, optical engineering. medical science, space engineering and material engineering etc. The friction drive system is very simple and quiet, compared to ball screw system. We find a problem at the simultaneous 3 axis and suggest a solution. Also, when we manufactured a micro lens. find a problem and solution.

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Simultaneous Optimization for Robust Parameter Design Using Signal-to-Noise Ratio

  • Kwon, Yong Man
    • 통합자연과학논문집
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    • 제13권3호
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    • pp.92-96
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    • 2020
  • Taguchi's robust parameter design is an approach to reduce the performance variation of quality characteristics in products and processes. In robust design, the signal-to-noise ratio (SN ratio) was used to find the optimum condition to minimize the variation of quality characteristics as much as possible and bring the average of quality characteristics closer to the target value. In this paper, we propose a simultaneous optimization method based on a linear model of the SN ratio as a method to find the optimal condition of the control factor in case of multi-characteristics. In addition, the proposed method and the existing method were compared and studied by taking actual cases.

송엽 추출물을 이용한 카드뮴 독성의 해독에 관한 연구 (A Study on Antitoxic Effects of Pine Leaf Extracts against Cadmium Toxicity in Rats)

  • 이종섭;박경옥
    • 한국환경보건학회지
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    • 제22권3호
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    • pp.88-97
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    • 1996
  • This study was conducted to investigate the antitoxic effects of Pine Leaf extracts against cadmium toxicity. The experimental rats were divided into 5 groups, such as control group cadmium alone treatment group and simultaneous treatment groups of cadmium and three doses of Pine Leaf extracts. Each group was administered with different dose of Pine Leaf extracts such as 0.5 mg, 2.5 mg, 5.0 mg/kg wet weight in pallets for 12 weeks. Cadmium Chloride($CdCl_2$) was administered by 4 mg/kg body weight. The results were summarized as follows: The simultaneous administration of cadmium and Pine Leaf significantly more decreased cadmium concentration in liver tissues compared to the administration of cadmium only. When blood were measured, no significantly difference in haemoglobin, haematocrit, erythrocyte values compared to the administration of cadmium only, but RBC significantly more increased. The simultaneous administration of cadmium and Pine Leaf more no sigmificantly difference metallothionein concentration in liver than the administration of cadmium only. There were showed the histopathological slight changes in the liver and kidney tissues of rats.

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직렬연결된 저항형 한류기의 동시퀜치 현상 (Simultaneous quenching phenomena of resistive superconducting fault current limiter connected in series)

  • 최효상;김혜림;임해용;김인선;현옥배
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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    • pp.91-94
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    • 2000
  • We fabricated resistive super- conducting fault current limiters (SFCL) based on YBCO thin films grown on 2" diameter $Al_{2}O_{3}$ substrates. Two SFCLs with nearly identical properties. two SFCLs with nearly identical properties were connected in series to investigate simultaneous quenching. There was a difference of several half cycles in their quench starting time, although the difference was not more than 0.1 msec when they were operated separately. This imbalance was removed by connecting a shunt resistor to an SFCL in parallel. Increased power input at high voltages also reduced the initial imbalance in power dissipation. Further efforts on the simultaneous quench in SFCLs connected in series are on the way through methods such as the artificial control of quench speed.peed.

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SIMULTANEOUS SPEED AND ROTOR TIME CONSTANT IDENTIFICATION OF AN INDUCTION MOTOR DRIVE BASED ON THE MODEL REFERENCE ADAPTIVE SYSTEM COMBINED WITH A FUZZY RESISTANCE ESTIMATOR

  • Soltani, Jafar;Mizaeian, Behzad
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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    • pp.11-16
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    • 1998
  • In this paper, simultaneous estimation of rotor speed and time constant for a voltage source inverter (VSI) fed induction motor drive are disccussed. The theory is based on the Model Reference Adaptive System (MRAS). The identifier executes Simultaneous rotor speed and time constant so that vector control of the induction may be achieved in the rotor-flux oriented reference frame. Furthermore, to eliminate the offset error caused by the change in the stator resistance, a fuzzy resistance regulator is also designed which operates in parallel with the rotor speed and time constant identifier

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주파수 가중치를 고려한 승차감의 향상을 위한 차량 현가장치의 동시최적화 (Simultaneous Optimization of Vehicle Suspensions for the Improvement of Frequency-weighted Riding Comfort)

  • 김창동;정의봉
    • 소음진동
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    • 제5권1호
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    • pp.29-35
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    • 1995
  • This paper presents the simultaneous optimal design of structure and LQG control systems for the improvement of riding comforts of active vehicle suspension systems. The performance index of riding comforts is extended to include frequency-weighted acceleration in the quadratic cost functional. Janeway human response curve with respect to acceleration is used to verify the usefulness of the presented method. The method is applied to a half model of an active vehicle suspension systems with elastic body moving on randomly profiled road. The values of stiffness of suspensions are used for the structural design variables. The conjugate gradient method is used for optimization. The simulated results of simultaneous optimization with frequency-weighted cost functional are compared with those without frequency- weighted cost functional.

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Simultaneous Determination of Cinnamaldehyde and Coumarin in Oryeong-san using HPLC with Photodiode Array Detector

  • Seo, Chang-Seob;Shin, Hyeun-Kyoo
    • 대한한의학방제학회지
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    • 제18권2호
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    • pp.251-257
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    • 2010
  • Objectives : To develop and validate High-performance liquid chromatography-photodiode array methods for simultaneous determination of two constituents in Oryeong-san(ORS). Methods : Reverse-phase chromatography using a Gemini C18 column operating at $40^{\circ}C$, and photodiode array(PDA) detection at 280 nm, were used for quantification of the two marker components of ORS. The mobile phase using a gradient flow consisted of two solvent systems. Solvent A was $H_2O$ and solvent B was acetonitrile. Results : Calibration curves were acquired with correlation coefficient ($r^2$)>0.9999, and the relative standard deviation(RSD) values(%) for intra- and inter-day precision were not exceed 1.0%. The recovery rate of each compound was in the range of 93.01-104.16%, with an RSD less than 2.0%. The contents of two compounds in ORS were 1.10-3.72 mg/g. Conclusions : The established HPLC method will be helpful to improve quality control of ORS.

카드뮴 중독에 대한 산두근 추출액의 해독효과에 관한 연구 (A Study on the Effects of Radix Menispermi Extracts Against Cadmium Chloride Sub-chronic Toxicity in Rats)

  • 이종섭;박경옥;이정미
    • Toxicological Research
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    • 제12권1호
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    • pp.59-68
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    • 1996
  • This study was conducted to investigate the antitoxic effects of Radix Menispermi extracts against cadmium toxicity. The experimental rats were divided into 5 groups such as control group, cadmium alone treatment group and simultaneous treatment groups of cadmium and three doses of Radix Menispermi extracts. Each group was administered with different dose of Radix Menispermi extracts such as 0.55 mg, 1.10 mg, 1.65 mg/kg wet weight in pallets for 12 weeks. Cadmium Chloride $(CdCl_2)$ was administered by 4 mg/kg body weight. The results were summarized as follows: 1. The simultaneous administration of cadmium and Radix Menispermi significantly more decreased cadmium concentration in liver tissues compared to the administration of cadmium only (P < 0.05). 2. When blood were measured, no significantly difference in haemoglobin, haematocrit, erythrocyte values compared to the administration of cadmium only. 3. The simultaneous administration of cadmium and Radix Menispermi more increased metallothionein concentration in liver than the administration of cadmium only (P < 0.05). 4. There were the histopathological slight changes in the liver and kidney tissues of rats.

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침(鍼)과 한약(韓藥) 그리고 비침습 혈관 레이저를 이용한 두통(頭痛) 치료 효과 (THE EFFECT OF SIMULTANEOUS TREATMENT WITH ACUPUNCTURE, HERB MEDICATION AND NON-INVASIVE LASER IRRADIATION OF BLOOD VESSEL ON HEADACHE)

  • 황선미;이승진;정대규
    • 동의신경정신과학회지
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    • 제12권2호
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    • pp.95-102
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    • 2001
  • 1. Purpose : The present study was carried out to evaluate the effects of simultaneous treatment with acupuncture, herb medication and non-invasive laser irradiation of blood vessel on the pain control of primary headache. 2. Methods : 30 outpatients who visited in the oriental medical hospital of Kyungsan University from April 10, 2001 to Oct. 10, 2001, based on symptoms and the results of pulse diagnosis, stress test(ABR-2000) and iridology test, were observed on the pain control of primary headache like tension or stress-induced headache. 1)Acupuncture and herbal medicine : Acupuncture treatment and herb medication widely used for headache were carried out simultaneously. 2)Non-invasive laser irradiation : Laser irradiation was undertaken on brachial vein with Lapex-2000 for 30minutes a day for 5 to 15days. 3. Result and Conclusion: In patients with headache, triglyceride mean values decreased from $168.57{\pm}26.90mg/dL$ to $154.23{\pm}28.66mg/dL$ and total cholesterol mean values decreased from $202.23{\pm}22.17mg/dL$ to $194.57{\pm}19.32mg/dL$, after simultaneous treatment with acupuncture, herb medication and non-invasive laser irradiation of blood vessel. And these results suggest that these simultaneous treatment has significant effects in tension and stress-induced headache.: Experiment subjects considered as shown the validity in the headache estimated 80%.

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