• Title/Summary/Keyword: disturbance factor

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Clinical Outcomes of the Surgical Excision of the Ganglion Cyst Causing Compressive Neuropathy - A Review of Twelve Collected Cases - (압박 신경병증을 일으킨 결절종의 수술적 절제의 임상적 결과)

  • Jung, Sung-Taek;Cho, Seong-Beom;Moon, Eun-Sun;Lee, Jae-Joon;Kim, Ki-Hyeoung;Yang, Hyun-Kee
    • The Journal of the Korean bone and joint tumor society
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    • v.12 no.1
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    • pp.63-70
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    • 2006
  • Purpose: The purpose of current study was to review the surgical treatment results in patients with a ganglion cyst involving peripheral nerves and to suggest the poor prognostic factor. Materials and Methods: Twelve patients having neurologic symptoms caused by ganglion cyst were treated operatively between 1995 and 2000. The peripheral nerves involved were the tibial nerve in three patients, suprascapular nerve, common peroneal nerve, radial nerve, and ulnar nerve in two patients each, and median nerve in one patient. Pain was present in six patients, sensory disturbance or motor weakness was seen in seven patients each; and sensory disturbance and motor weakness were concurrently present in four patients. Results: In all six patients who complained of preoperative pain, the pain was resolved after surgery. Improvements were seen in five of seven patients who had preoperative sensory disturbance and in all patients who had preoperative motor weakness. Complete sensory recovery was obtained in only two of four patients with preoperative sensory disturbance and motor weakness, indicating a poor prognosis factor. Conclusion: Early accurate diagnosis and early excision of these ganglion cysts causing compression neuropathy could produce excellent clinical results.

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Development of a Questionnaire to Measure Family Stress among Married Working Women (가족스트레스 측정 도구 개발 - 기혼 여성근로자를 대상으로 -)

  • Kim Gwang-Suk;Cho Won-Jung
    • Journal of Korean Academy of Nursing
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    • v.36 no.5
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    • pp.761-769
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    • 2006
  • Purpose: Even though a number of studies have suggested that appropriate measuring instruments of family stress for working women have to be developed, the validity and reliability of the instruments used have not been consistently examined. The purpose of the present study was to develop a sensitive instrument to measure family stress for married working women, and to test the validity and reliability of the instrument. Method: The items generated for this instrument were drawn from a comprehensive literature review Twenty four items were developed through evaluation by 10 experts and twenty one items were finally confirmed through item analysis. Psychometric testing was preformed and confirmed with a convenient sample of 240 women employed in the industrial sector. Result: Four factors evolved by factor analysis, which explained 50.5% of the total variance. The first factor 'Cooperation' explained 28.1%, 2nd factor 'Satisfaction with relationships' 10.6%, 3rd factor 'Democratic and comfortable environment' 6.3%, and 4th factor 'Disturbance of own living' 5.5%, Cronbach's coefficient of this instrument was 0.86. Conclusion: The study supports the validity and reliability of the instrument.

Stochastic response of colored noise parametric system

  • Heo, Hoon;Paik, Jong-Han;Oh, Jin-Hyoung
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10b
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    • pp.451-455
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    • 1993
  • Interaction between system and disturbance results in system with time-dependent parameter. Parameter variation due to interaction has random characteristics. Most of the randomly varying parameters in control problem is regarded as white noise random process which is not a realistic model. In real situation those random variation is colored noise random process. Modified F-P-K equation is proposed to get the response of the random parametric system using some correction factor. Proposed technique is employed to obtain the colored noise parametric system response and confirmed via Monte-Carlo Simulation.

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Modular Photovoltaic PCS with High-frequency Isolation (고주파 절연 모듈형 Photovoltaic PCS)

  • Kwon, Jung-Min;Kwon, Bong-Hwan
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.132-135
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    • 2005
  • A modular photovoltaic PCS with high-frequency isolation is proposed. The proposed system consists of a SEPIC converter and a full-bridge inverter. Using the power slope versus voltage of the PV array, the MPPT controller is proposed that produces a smooth transition to the maximum power point. The disturbance of the line voltage is detected using a fast sensing technique. Experimental results obtained on a 500W prototype show high performance such as almost unity power factor, $90\%$ power efficiency, $3.6\%$ THD.

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Autopilot Design with Two Degree of Freedom $H_{\infty}$ Control Method (2자유도 $H_{\infty}$제어기를 이용한 비행체 자동조종장치 설계)

  • 최광진;황준하;권오규
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1304-1307
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    • 1996
  • In this paper, we present a robust Two Degree of Freedom (TDF) $H_{\infty}$ controllers for a missile system. The feedback controller is designed to meet robust stability and disturbance rejection specifications while the prefilter is used to improve the robust model matching properties of the closed loop system. As the perturbed model, we use the normalized coprim factor perturbations. These controllers are designed using $H_{\infty}$ optimization procedures, and applied to a missile model via simulation.

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Energy Conversion in the Rossby Adjustment Process for Step-Like Initial Disturbances (初期攪亂에 의한 로스비 形過程에 있어서의 에너지 換)

  • 성영호
    • 한국해양학회지
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    • v.21 no.3
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    • pp.131-135
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    • 1986
  • Conversion of energy from potential to kinetic form is considered when a step-like initial disturbance is released to reach a final steady state. For small amplitute disturbances, linearization can be made and it is proved analytically that the conversion factor (ratio of generated kinetic to loss in potential energies) asymptotically approaches to 1/3 as the horizontal scale of disturbances becomes large.

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Analysis of Output Voltage Variation of a Voltage Disturbance Generator with the Variation of Load Power Factor in Voltage Sag Mode (전력변동 발생기의 전압새그 모드 동작시 부하 역률에 따른 출력 전압 변동 해석)

  • Jeong, Hye-Soo;Kim, Hak-Soo;Jung, Jae-Hun;Nho, Eui-Cheol
    • Proceedings of the KIPE Conference
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    • 2015.11a
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    • pp.179-180
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    • 2015
  • 본 논문에서는 변압기 기반 전압변동 발생기의 외란 발생 동작 시 부하단의 전압 특성을 분석하였다. 부하 역률에 따른 전압강하의 차이를 분석하였고 역률이 0.8 지상인 경우 전압강하가 가장 크게 발생함을 실험을 통하여 확인하였다.

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A Case of Heel Reconstruction with a Reverse Sural Artery Flap in a Hemophilia B Patient

  • Lee, Byung-Kwon;Shim, Jeong-Su
    • Archives of Plastic Surgery
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    • v.39 no.2
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    • pp.150-153
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    • 2012
  • Hemophilia B is a rare blood coagulation disorder. Complications such as bleeding and hematoma can cause necrosis of flaps, wound disruption, and the disturbance of wound healing. In particular, guidelines for flap operations in hemophilia B patients have still not been defined, and case reports are rare. We reconstructed the heel of a 41-year-old male hemophilia B patient using a reverse sural artery flap operation. The patient presented with mild hemophilia, having 27% of the normal value of coagulation factor IX. Coagulation and the changing value of the coagulation factor were regularly measured, and 70% of the normal value of coagulation factor IX was maintained through the injection of recombinant coagulation factors and antihemorrhagics. Hematoma developed twice (postoperative day [POD] 5 and POD 7) and in each case the hematoma was removed. Injections of recombinant coagulation factors and antihemorrhagics were continuously administered until postoperative week 2. When the coagulation factors were within normal ranges. In this article, a hemophilia B patient underwent reverse sural artery flap surgery and the healing progress was analyzed. We conclude that higher than baseline levels of coagulation factors are needed for successful healing in reverse sural artery flap surgery.

Overlay Multicast Update Strategy Based on Perturbation Theory

  • Shen, Ye;Feng, Jing;Ma, Weijun;Jiang, Lei;Yin, Min
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.1
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    • pp.171-192
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    • 2017
  • The change of any element in the network is possible to cause performance degradation of the multicast network. So it is necessary to optimize the topology path through the multicast update strategy, which directly affects the performance and user experience of the overlay multicast. In view of the above, a new multicast tree update strategy based on perturbation theory Musp (Multicast Update Strategy based on Perturbation theory) is proposed, which reduces the data transmission interruption caused by the multicast tree update and improves user experiences. According to the multicast tree's elements performance and the topology structure, the Musp strategy defines the multicast metric matrix and based on the matrix perturbation theory it also defines the multicast fluctuation factor. Besides it also demonstrates the calculability of the multicast fluctuation factor presents the steps of the Musp algorithm and calculates the complexity. The experimental results show that compared with other update strategies, as for the sensitivity of the multicast fluctuation factor's energized multicast tree to the network disturbance, the maximum delay of the Musp update strategy is minimal in the case of the local degradation of network performance.

Seismic bearing capacity of shallow embedded strip footing on rock slopes

  • Das, Shuvankar;Halder, Koushik;Chakraborty, Debarghya
    • Geomechanics and Engineering
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    • v.30 no.2
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    • pp.123-138
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    • 2022
  • Present study computes the ultimate bearing capacity of an embedded strip footing situated on the rock slope subjected to seismic loading. Influences of embedment depth of strip footing, horizontal seismic acceleration coefficient, rock slope angle, Geological Strength Index, normalized uniaxial compressive strength of rock mass, disturbance factor, and Hoek-Brown material constant are studied in detail. To perform the analysis, the lower bound finite element limit analysis method in combination with the semidefinite programming is utilized. From the results of the present study, it can be found that the magnitude of the bearing capacity factor reduces quite substantially with an increment in the seismic loading. In addition, with the increment in slope angle, further reduction in the value of the bearing capacity factor is observed. On the other hand, with an increment in the embedment depth, an increment in the value of the bearing capacity factor is found. Stress contours are presented to describe the combined failure mechanism of the footing-rock slope system in the presence of static as well as seismic loadings for the different embedment depths.