• Title/Summary/Keyword: Simple Technique

Search Result 3,403, Processing Time 0.027 seconds

A Simple Resonant Link Inverter for a Discrete-Time Current Control (이산 전류 제어를 위한 공진형 인버터)

  • 오인환;정영석;주형길;윤명중
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.3 no.1
    • /
    • pp.36-45
    • /
    • 1998
  • A simple source voltage clamped resonant link (SVCRL) inverter is proposed to clamp the DC link voltage to the input source voltage and reduce the current rating of resonant inductor. The current control of a permanent magnet synchronous motor (PMSM) using a predictive current control technique (PCCT) employing the SVCRL inverter is also investigated to overcome the disadvantage of the current regulated delta modulation (CRDM) control technique. By using the PCCT based on the discrete model of a PMSM and estimation of back EMF, the minimized current ripple with small number of switchings can be obtained. Finally, the comparative computer simulation and experimental results are given to show the usefulness of the proposed technique.

CAD design of miniaturized dielectric filer with attenuation pole (감쇄극을 갖는 소형 유전체 여파기의 CAD 설계)

  • 이문규;남상욱;염경환;홍성용
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.21 no.9
    • /
    • pp.2481-2493
    • /
    • 1996
  • A simple iterative design method is presented for the miniaturized dielectric filter with finite transimmission zeros. Circuit-network transformations are used to place transission zeros in the stop band. This method is simple and quick compared with conventional pole-synthesis methods. the design of the coupling EM patternof the filter needs the much computation time because its design is carried out through the field simulatior. In this paper, an efficient implementation technique of coupling circuit parameters is presented. This technique uses a linear mapping function between the circuit parameter domain and EM parameter domain to save the high computational time of EM simulator. A narrow band asymmetric filter with a transmission zero is designed and fiblicated through these technique in 1900 MHz band.

  • PDF

Application of Hand Towel Drape over Dingman Mouth Gag

  • Choi, Kyeong Beom;Park, Myong Chul
    • Archives of Craniofacial Surgery
    • /
    • v.16 no.1
    • /
    • pp.29-30
    • /
    • 2015
  • In cleft palate surgery, the environment is especially critical when suturing. Encum-bered, obstructive space in the environment can hinder a suture while using the Dingman mouth gag. We introduced a novel but simple draping technique. A simple hand towel is placed over the gag. A hole is cut out in the middle according to each patient's mouth. After making the hole, the hand towel is soaked in water and gently squeezed. Then the towel is properly placed over the Dingman mouth gag. Dripping water on the hand towel during the suture helps keep it in place. Using this draping technique, we cut 14 minutes of operation time compared to the average operation time of the past 2 years. There were several disadvantages in previous draping method. First, long suture material may easily get caught. Second, the operation field can easily be contaminated. Third, focusing on the operation becomes difficult due to the obstruction. This draping technique can compensate for the disadvantages of the previous Dingman mouth gag.

Caudal Anesthesia for pediatric Inguinal Region Surgery (유.소아 서혜부 수술을 위한 미추마취)

  • Lee, Kyeung-Sook;Park, Dae-Pal
    • Journal of Yeungnam Medical Science
    • /
    • v.7 no.1
    • /
    • pp.127-131
    • /
    • 1990
  • Pediatric caudal anesthesia was done in 50 infants and children under 10 years of age, who were to undergo surgery of inguinal region. All cases were given 10mg/kg body weight of 1% lidocaine solution with epinephrine 1:200,000. The results were as follows : 1) Pediatric caudal anesthesia was simple, easy and reliable in technique. 2) Additional intravenous administration of Ketamine or pentothal sodium was needed. ie, to provide a more cooperative state. 3) Anesthetic effect was judged very Excellent. 4) Cardiovascular and respiratory changes were minimal. Author's came to conclusion that caudal anesthesia for pediatric inguinal region surgery is reliable, simple in technique, favorable to surgeon, and is considered to be a good technique for pediatric anesthesia.

  • PDF

Simple Method to Produce in vitro Pyrenophora tritici-repentis Teleomorph

  • Benslimane, Hamida
    • The Plant Pathology Journal
    • /
    • v.30 no.4
    • /
    • pp.437-439
    • /
    • 2014
  • A fungus Pyrenophora tritici-repentis induces tan spot of wheat which is a foliar disease that causes yield loss to wheat crops worldwide. In this study, a new, simple and non-costly technique was performed to produce the sexual stage of this fungus in culture, within 9 weeks using wheat straw. This protocol will be helpful to researchers studying the biology of sexual stage development, disease epidemiology and genetics of this fungus.

Algebraic Observer Design for Descriptor Systems via Block-pulse Function Expansions (블록펄스함수 전개를 이용한 Descriptor 시스템의 대수적 관측기 설계)

  • 안비오
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.50 no.6
    • /
    • pp.259-265
    • /
    • 2001
  • In the last two decades, many researchers proposed various usages of the orthogonal functions such as Walsh, Haar and BPF to solve the system analysis, optimal control, and identification problems from and algebraic form. In this paper, a simple procedure to design and algerbraic observer for the descriptor system is presented by using block pulse function expansions. The main characteristic of this technique is that it converts differential observer equation into an algerbraic equation. And furthermore, a simple recursive algorithm is proposed to obtain BPFs coefficients of the observer equation.

  • PDF

A SIMPLE APPROACH TO THE WORKLOAD ANALYSIS OF M/G/1 VACATION QUEUES

  • Kim, Nam-Ki;Park, Yon-Il;Chae, Kyung-Chul
    • Journal of the Korean Statistical Society
    • /
    • v.33 no.2
    • /
    • pp.159-167
    • /
    • 2004
  • We present a simple approach to finding the stationary workload of M/G/1 queues having generalized vacations and exhaustive service discipline. The approach is based on the level crossing technique. According to the approach, all that we need is the workload at the beginning of a busy period. An example system to which we apply the approach is the M/G/1 queue with both multiple vacations and D-policy.

Effect of Calcium Carbonate on Properties of Paper in Alkali Paper Masking (중성초지에서 탄산칼슘의 성질이 종이의 물성에 미치는 영향)

  • 신종순
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.8 no.1
    • /
    • pp.71-87
    • /
    • 1990
  • This paper presents a simple algorithm to obtain three dimensional information of an object. In the preprocessing of the stereo matching,feature point informations of stero image must be less sensitive to noise and well liked the correspondance problem. This paper described a simple technique of struture feature extraction of 3-D object and used edge-end point expanding method for unconnected line instade of Hough transform. The feature such as corner point and their angles are used for matching problem. The experimental results show that the described algorithm is a useful method for stereo correspondence problem.

  • PDF

A Numerical Ductile Failure Simulation Technique Based on Phenomenological Damage Concept (수치해석을 이용한 현상학적 연성파괴 모사 기법)

  • Kim, Nak-Kyun;Oh, Chang-sik;Min, Sung-hwan;Kim, Yun-Jae
    • Transactions of the Korean Society of Pressure Vessels and Piping
    • /
    • v.5 no.2
    • /
    • pp.27-34
    • /
    • 2009
  • This paper proposes a simple numerical method to simulate ductile failure behaviors. The method is based on finite element analysis with a simple damage theory. To validate the proposed method, simulated results are compared with experimental data. Despite its simplicity, the proposed method well predicts experimental results systematic analyses are also performed to investigate the effect of the element size.

  • PDF