• Title, Summary, Keyword: instrumentation

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Instrumentation Failure after Partial Corpectomy with Instrumentation of a Metastatic Spine

  • Park, Sung Bae;Kim, Ki Jeong;Han, Sanghyun;Oh, Sohee;Kim, Chi Heon;Chung, Chun Kee
    • Journal of Korean Neurosurgical Society
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    • v.61 no.3
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    • pp.415-423
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    • 2018
  • Objective : To identify the perioperative factors associated with instrument failure in patients undergoing a partial corpectomy with instrumentation (PCI) for spinal metastasis. Methods : We assessed the one hundred twenty-four patients with who underwent PCI for a metastatic spine from 1987 to 2011. Outcome measure was the risk factor related to implantation failure. The preoperative factors analyzed were age, sex, ambulation, American Spinal Injury Association grade, bone mineral density, use of steroid, primary tumor site, number of vertebrae with metastasis, extra-bone metastasis, preoperative adjuvant chemotherapy, and preoperative spinal radiotherapy. The intraoperative factors were the number of fixed vertebrae, fixation in osteolytic vertebrae, bone grafting, and type of surgical approach. The postoperative factors included postoperative adjuvant chemotherapy and spinal radiotherapy. This study was supported by the National Research Foundation grant funded by government. There were no study-specific biases related to conflicts of interest. Results : There were 15 instrumentation failures (15/124, 12.1%). Preoperative ambulatory status and primary tumor site were not significantly related to the development of implant failure. There were no significant associations between insertion of a bone graft into the partial corpectomy site and instrumentation failure. The preoperative and operative factors analyzed were not significantly related to instrumentation failure. In univariable and multivariable analyses, postoperative spinal radiotherapy was the only significant variable related to instrumentation failure (p=0.049 and 0.050, respectively). Conclusion : When performing PCI in patients with spinal metastasis followed by postoperative spinal radiotherapy, the surgeon may consider the possibility of instrumentation failure and find other strategies for augmentation than the use of a bone graft for fusion.

A Method of Image Identification in Instrumentation

  • Wang, Xiaoli;Wang, Shilin;Jiang, Baochen
    • Journal of Information Processing Systems
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    • v.14 no.3
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    • pp.600-606
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    • 2018
  • Smart city is currently the main direction of development. The automatic management of instrumentation is one task of the smart city. Because there are a lot of old instrumentation in the city that cannot be replaced promptly, how to makes low-cost transformation with Internet of Thing (IoT) becomes a problem. This article gives a low-cost method that can identify code wheel instrument information. This method can effectively identify the information of image as the digital information. Because this method does not require a lot of memory or complicated calculation, it can be deployed on a cheap microcontroller unit (MCU) with low read-only memory (ROM). At the end of this article, test result is given. Using this method to modify the old instrumentation can achieve the automatic management of instrumentation and can help build a smart city.

A Suspension Control of A PM-based Magnetic Suspension System (영구자석을 포함한 자기부상시스템의 부상제어)

  • Kim, Jong-Moon;Kim, Choon-Kyung;Park, Min-Kook;Chun, Jong-Min;Pyon, Han-Sub
    • Proceedings of the KIEE Conference
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    • pp.2264-2266
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    • 2001
  • In this paper, some suspension results for a magnetic suspension system with permanent magnet are presented. The electromagnetic model using the equivalent magnetic circuit is shown. And some control simulation results using Matlab/Simulink S/W are presented.

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Development of Electromotion Auxiliary Bicycle (전동보조자전거의 개발)

  • Lee, Hyung-Ki;Choe, Yeon-Wook;Park, Han-Seok;An, Young-Joo;Shin, Bong-Chul
    • Proceedings of the KIEE Conference
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    • pp.2033-2035
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    • 2001
  • 본 연구는 기존의 자전거에 전기 구동장치를 장착시켜서 자전거의 페달링에 의하여 검출된 답력을 이용한 보조 동력 구동장치에 대한 개발이다. 답력의 검출은 불시의치차를 이용한 동력 전달장치를 이용하였다. 이 장치의 입력기어에서 출력기어로 동력을 전달하는 아이들 피니언 기어와 결합된 캐리어를 동력 전달시 발생하는 반력에 의한 각도를 이용하여 토크량을 측정하였다. 동력전달을 할 경우 발생하는 반력에 의한 회전각을 자기센서를 이용하여 답력을 측정하였다. 이 답력을 구동회로에 인가하여 보조동력을 자전거에 인가함에 따라 주행을 쾌적하게 하도록 개발하였으며 실험을 통하여 실용성을 고찰하였다.

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Development of LVAD Control System using Micro Controller (마이크로 컨트롤러를 이용한 전기유압식 좌심실보조기 제어시스템의 개발)

  • Lee, S.W.;Chung, C.I.;Choi, J.W.;Kim, H.C.;Min, B.G.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.11
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    • pp.127-129
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    • 1992
  • In this paper, we describe about control system for eletro-hydraulic LVAD(Left Ventricular Assist Device) and control algorithm for two operation mode. One is asynchronous operation mode and the other is synchronous operation mode synchronized with natural heart's R pulse. We also present implementation method of software PI algorithm for velocity control of motor used in LVAD system and its response.

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Speed and efficiency control of induction motors via asymptotic decoupling

  • Kim, Gyu-Sik;Ha, In-Joong;Ko, Myoung-Sam;Kim, Dong-Il;Kim, Jeom-Geun
    • 제어로봇시스템학회:학술대회논문집
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    • pp.1041-1046
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    • 1989
  • In this paper, we attempt to control induction motors with high power efficiency as well as high dynamic performance by utilizing the recently developed theories: singular perturbation technique and noninteracting feedback control. Our controller does not need the transformation between a d-q synchronously rotating frame and a x-y stator-fixed frame. It is computationally quite simple. Furthermore, it does not depend on the rotor resistance. To illuminate the practical significance of our results, we present simulation and experimental results as well as mathematical performance analysis.

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Fuzzy control system tuning by performance evaluation (성능평가에 의한 퍼지제어시스템 동조)

  • Jeong, Heon;Jeong, Chang-Gyu;Ko, Nack-Yong;Kim, Young-Dong;Choi, Han-Soo
    • Proceedings of the KIEE Conference
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    • pp.682-684
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    • 1995
  • The most effective way to improve the performance of a fuzzy controller may be to optimize look-up values. Look-up values are derived from processes used input-output scale factors, membership functions, rule base, fuzzy inference method and defuzzification. It is powerful way to modify or organize look-up table values. In this paper, We propose the look-up values self-organizing fuzzy controller(LSOFC). We use the plus-minus tuning method(PMTM), scanning values through the processes of addition and subtraction. We show the efficiency of this LSOFC by the results of simulation for nonlinear time-varying plant with unmodelled dynamics.

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A Experimental Study of Stochastic Controller Realizing Technique (실험적 연구를 통한 확률제어기 구현)

  • Lee, Jong-Bok;Kim, Yong-Kwan;Yoon, Young-Soo;Choi, Won-Seok;Heo, Hoon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • pp.715-718
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    • 2002
  • A control strategy for a dynamic system under Irregular disturbance by using stochastic controller is developed. In order to design stochastic controller. system dynamic model in real domain is transformed dynamic moment equation in stochastic domain by F-P-K approach. A study of real time control technique for stochastic controller is presented. The performance of stochastic controller is verified through experiment used by real time control technique method.

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Characteristics of Ultrasonic Motor using Voltage Control and Phase Difference Control (초음파 모터의 전압 및 위상차 제어 특성)

  • Shin, Duk;Kim, Dong-Ok;Ko, Nak-Yong;Choi, Han-Soo;Kim, Young-Dong
    • Proceedings of the KIEE Conference
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    • pp.949-952
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    • 1996
  • The ultrasonic motor(USM) has good characteristics such as compact size, silent motion, low speed, high torque and high speed response. The USM is driven by 2-phase AC electricity. The control parameters of USM are voltage, phase difference, frequency of input power, etc. In this paper, we propose voltage difference control. And we designed USM controller to adjust voltage and phase using pLSI(programmable Large Scale Integration). Voltage difference control has many advantages that are lower current, lower power than phase difference control. Especially there is nearly zero ampere at the zero point of speed and torque. we can apply this voltage difference control to the compliance control of DD manipulator.

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Robust Control of Uncertainty Systems by Fuzzy Auto-Tuning (Fuzzy 자동동조에 의한 불확실성 공정의 견실제어)

  • Ryu, Y.G.;Choi, J.N.;Kim, J.K.;Mo, Y.S.;Hwang, H.S.
    • Proceedings of the KIEE Conference
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    • pp.504-506
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    • 1999
  • In this paper, we propose a method which control parametric uncertainty systems using PID controller by fuzzy auto tuning. We get the error and the error change rate of plant output correspond to the initial value of parameter using the Ziegler-Nickols tuning and determine the new proportional gain$(K_p)$ and the integral time $(T_i)$ from fuzzy tuner by the error and error change rate of plant output as a membership function of fuzzy theory. The Fuzzy Auto-tuning algorithm for PID controller operate to adapt variable parameter of plant in parametric uncertainty systems. It is shown this method considerably improve the transient response at computer simulation.

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