• Title/Summary/Keyword: Reference Source

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Stimulated Brillouin scattering using a source with a few axial modes and an optical fiber ring resonator (수개의 종모드를 갖는 광원에 의한 고리형광섬유공진기에서의 유도브릴루앙산란)

  • 이현재;윤병호;이동호;전영윤;김향균
    • Korean Journal of Optics and Photonics
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    • v.6 no.4
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    • pp.324-330
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    • 1995
  • Stimulated Brillouin scattering theory is described in an optical fiber. Frequency change with an optical heterodyne method is analyzed between reference signal of a source and stimulated Brillouin scattering signal in an optical fiber. By coupling a source with a few axial modes and an optical fiber ring resonator, Brillouin scattering is studied with a spectrum analyzer. Using reference beating signal of a source, we have reduced the Brillouin beating frequency from 13 GHz range to below GHz. Experimentally, we can see the Brillouin beating frequency from 13 GHz range to below GHz with a dispersion shifted fiber (1.32 GHz), Ti-doped fiber (900 MHz) and single mode optical fiber (870 MHz). MHz).

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Modelling and Performance Analysis of UPQC with Digital Kalman Control Algorithm under Unbalanced Distorted Source Voltage conditions

  • Kumar, Venkateshv;Ramachandran, Rajeswari
    • Journal of Power Electronics
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    • v.18 no.6
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    • pp.1830-1843
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    • 2018
  • In this paper, the generation of a reference current and voltage signal based on a Kalman filter is offered for a 3-phase 4wire UPQC (Unified Power Quality Conditioner). The performance of the UPQC is improved with source voltages that are distorted due to harmonic components. Despite harmonic and frequency variations, the Kalman filter is capable enough to determine the amplitude and the phase angle of load currents and source voltages. The calculation of the first state is sufficient to identify the fundamental components of the current, voltage and angle. Therefore, the Kalman state estimator is fast and simple. A Kalman based control strategy is proposed and implemented for a UPQC in a distribution system. The performance of the proposed control strategy is assessed for all possible source conditions with varying nonlinear and linear loads. The functioning of the proposed control algorithm with a UPQC is scrutinized and validated through simulations employing MATLAB/Simulink software. Using a FPGA SPATRAN 3A DSP board, the proposed algorithm is developed and implemented. A small-scale laboratory prototype is built to verify the simulation results. The stated control scheme for the UPQC reduces the following issues, voltage sags, voltage swells, harmonic distortions (voltage and current), unbalanced supply voltage and unbalanced power factor under dynamic and steady-state operating conditions.

Error-Resilient Video Transmission Techniques over Unreliable Networks (비 신뢰성 네트워크에서 에러를 극복하는 비디오 전송 기법)

  • 노경택
    • Journal of the Korea Society of Computer and Information
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    • v.6 no.3
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    • pp.50-55
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    • 2001
  • We review error resilience techniques for real-time video transport over unreliable networks. For error control on the source coding level, each decoder has to make provisions for error detection, resynchronization. and error concealment. and we review techniques suitable for that purpose. Further, techniques are discussed for intelligent processing of acknowledgment information by the coding control to adapt the source coder to the channel. We review and compare error tracking, error confinement. and reference picture selection techniques for channel-adaptive source coding. We review how feedback-based source codings are related with the precompressed video stored on a media server

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A comprehensive review on Tukhme Kunjud (Sesamum indicum Linn.) with special reference to Unani System of Medicine.

  • Khatoon, Rizwana;Abbasi, Hana;Aslam, Mohammad;Chaudhary, Shahid Shah
    • CELLMED
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    • v.9 no.3
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    • pp.2.1-2.7
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    • 2019
  • Sesame (Sesamum indicum L.) is a rich source of edible oil most commonly it is used as a food product mainly in bakeries and also use as a common source of oil in daily kitchen needs. Due to the presence of some special phytochemicals like proteins, fibers, oil, minerals and antioxidants it is highly used for medicinal and therapeutic purposes. It is a good source of energy and act as an antiaging agent. Its seeds are used as Anti-helmintic, antihypertensive, antimicrobial, cytotoxic and Hepatoprotective but its seed coat which is a byproduct of sesame and a cherished source of fibers is normally use for animal feedstuff. In Unani system of medicine it is used both as drug & diet (dawa wa ghida). In classical Unani literature it is indicated in various disorders like Asthma, Dry Cough, Gastritis (due to any drug, excessive use of alcohol), Dryness of Intestine, Dryness in throat, Renal Stone, Bleeding Piles, Amenorrhea, Retention of urine, Dysuria, Orchitis, Sexual Debility, Anorexia. The present review article, an attempt have been made to compile all the pharmacological and Pharmacognostical characters of Sesamum indicum with special reference to Unani literature.

A Study on the Development of Internet-based Reference Request System (인터넷 기반 참고질의시스템의 개발에 관한 연구)

  • 박준식;방대욱
    • Journal of Korean Library and Information Science Society
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    • v.32 no.1
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    • pp.1-31
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    • 2001
  • University libraries need the development of a common Internet-based reference request system in order to prevent duplicated investment and provide interoperability among them. This paper proposes a standard of Internet-based reference recluest system that serves reference request-responses and that provides reference source sites on the world wide web. Using this system, university libraries can cooperate other libraries with reference databases and may perform tasks of reference service efficiently.

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A Source-Related Approach for Discussion on Using Radionuclide-Contaminated Materials in Post-accident Rehabilitation

  • Kazuji Miwa;Takeshi Iimoto
    • Journal of Radiation Protection and Research
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    • v.48 no.2
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    • pp.68-76
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    • 2023
  • Background: In the process of discussion on the possibility of using radionuclide-contaminated soil and debris generated by radiation disasters, a strategy for the proper management of radiation exposure protection while considering the source of the contaminated materials is necessary. Materials and Methods: The radiological protection criteria that are likely to be applied to the source-related approach based on the International Commission on Radiological Protection recommendations and the International Atomic Energy Agency safety standards are summarized. We proposed five interpretations of radiation protection to contribute to the promotion of discussion on the possibility of using a part of low-level-radionuclide-contaminated soil and debris in the post-accident rehabilitation. Interpretations I to III are based on the idea of "using a reference level to protect the public in post-accident rehabilitation," whereas IV and V are based on the idea of "using the dose constraint to protect the public in the post-accident rehabilitation when the sources are handled in a planned activity." The former idea is subdivided into three based on the definition of the source, which is managed by the reference level, and the latter idea is divided into two depending on whether or not additional dose from using contaminated materials is deemed acceptable. Results and Discussion: To confirm the applicability of the five interpretations presented, we suggested the concrete values of protection criteria via two feasible cases. In this case study, we proposed radiation protection by the dose constraint based on the Interpretation IV and chose 1 mSv/yr for the public and 20 mSv/yr for workers dealing with radionuclide-contaminated materials. Conclusion: We concretely and systematically demonstrated how the concept of radiation protection can be applied to the process of discussion on the possibility of using radionuclide-contaminated materials within the framework of an international system of protection. This study's findings can provide necessary information to discuss the possibility of using radionuclide-contaminated materials as an alternative option for recovery and reconstruction after a radiation disaster from the viewpoint of radiation protection.

A Study on Source Current Control of Voltage Source PWM Converter based on Lossless Resonator (무손실 공진기를 가지는 전압형 PWM 컨버터의 전원전류 제어에 관한 연구)

  • Heo, T.W.;Shin, D.W.;Kim, G.H.;Jin, H.J.;Woo, J.I.
    • Proceedings of the KIEE Conference
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    • 1997.07f
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    • pp.2040-2042
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    • 1997
  • A voltage source PWM converter based on lossless resonator and a source current control system are proposed in this paper. It is proved that steady-state deviation reduces to zero from the transfer function of source current control system, owing to the lossless resonator. The system can be controlled by the feedback control only, because of no need to use a feedforward control in the proposed a source current control system. Therefore, as using lossless resonator, control system can be simply made up. Simulations are described in the case of difference between source current and source current reference.

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S-value of Radioiodine($^{131}I$) in Korean Reference Adult Male (한국 성인남성 표준인을 대상으로 한 방사성옥소($^{131}I$)의 S-value 도출)

  • Kim, Jung-Hoon;Lim, Chang-Seon;Whang, Joo-Ho
    • Journal of radiological science and technology
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    • v.31 no.1
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    • pp.41-47
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    • 2008
  • In order to better understand the effects of absorbed radioiodine upon Korean reference adult male, a mathematical phantom representation was contrived based on composite data of the physiology of Korean reference adult male. Using this, S-values of radioiodine($^{131}I$) per each organ were calculated. The calculated S-values were compared to the existing data described in the TM-8381 report of ORNLcalculated on the basis of an ICRP-23 reference male. The results indicated that S-values were higher for the phantom based on Korean reference adult male. The results of this study illustrate that, while the bio-chemical constitution of each source and target organ of the torso are important, the relative location of the organs and characteristics of the radionuclides also exert important influences.

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A Study on the operating of building equipment in apartment building - With reference to heating equipment and water-supply facilities - (고층 아파트의 건축설비 운용실태에 관한 연구 - 난방설비 및 급수설비를 중심으로 -)

  • 안창환
    • Journal of the Korean housing association
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    • v.2 no.2
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    • pp.35-40
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    • 1991
  • In this study, the operation(heating) period of heat source(boiler) machineries in apartment building for periodic heat load analysis has been established by investigating their heat source machineries actural operation period, energy consumption, the capacity of heat source machineries, and their building element. Thus, the purpose of this paper is at bring up the various pre-estimate expression for energy conservatiove, efficient operation and amount of water supplied.

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A New Controller of Single Phase Active Power Filter Using Rotating Synchronous Frame d-q Transformation (회전하는 동기 좌표계 d-q 변환을 이용한 단상 능동 전력 필터의 새로운 제어기)

  • Kang, Min Gu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.6
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    • pp.271-275
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    • 2014
  • A New Single Phase Active Power Filter Controller is proposed using Rotating Synchronous Frame d-q transformation. Instantaneous Active Power is calculated using d-q transformation. Average Value of Instantaneous Active Power is obtained using Low Pass Filter. Because power factor is corrected, source current is in phase with source voltage. Amplitude of source current is calculated using single phase power formula. Reference signal of compensated current of Active power filter is obtained from source current reference signal minus load current. Simulation is performed using hysteresis current controller in proposed new controller. Simulation result shows that because active power filter compensates load current, source current is in phase with source voltage and source current is sinusoidal. And Hilbert transformer is builded using all pass filter.