• 제목/요약/키워드: Non-isolated technique

검색결과 72건 처리시간 0.024초

Investigation of effectiveness of double concave friction pendulum bearings

  • Ates, Sevket
    • Computers and Concrete
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    • 제9권3호
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    • pp.195-213
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    • 2012
  • This paper presents the investigation of the stochastic responses of seismically isolated bridges subjected to spatially varying earthquake ground motions including incoherence, wave-passage and site-response effects. The incoherence effect is examined by considering Harichandran and Vanmarcke coherency model. The effect of the wave-passage is dealt with various wave velocities in the response analysis. Homogeneous firm, medium and soft soil conditions are selected for considering the site-response effect where the bridge supports are constructed. The ground motion is described by filtered white noise and applied to each support points. For seismic isolation of the bridge, single and double concave friction pendulum bearings are used. Due to presence of friction on the concave surfaces of the isolation systems, the equation of motion of is non-linear. The non-linear equation of motion is solved by using equivalent linearization technique of non-linear stochastic analyses. Solutions obtained from the stochastic analyses of non-isolated and isolated bridges to spatially varying earthquake ground motions compared with each other for the special cases of the ground motion model. It is concluded that friction pendulum systems having single and double concave surfaces have important effects on the stochastic responses of bridges to spatially varying earthquake ground motions.

Two-Inductor Non-Isolated DC-DC Converter with High Step-Up Voltage Gain

  • Lee, Sze Sing;Chu, Bing;Lim, Chee Shen;Lee, Kyo-Beum
    • Journal of Power Electronics
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    • 제19권5호
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    • pp.1069-1073
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    • 2019
  • In this paper, an alternative non-isolated DC-DC converter with a high voltage boosting capability is proposed. Two inductors are used and one of them has its flux linkage increases during its charging period to achieve a high step-up voltage gain. Among the three integrated capacitors, one portrays the partial characteristic of the switched-capacitor technique, while the other two are connected in series across the load. With the two switches controlled using the same duty cycle, the proposed topology demonstrates the merits of a higher and wider range of step-up voltage gain when compared with recent topologies. In addition, a reduction in loss is induced and a higher efficiency is ensured with all the voltage stresses constrained within the output voltage. Operation of the proposed converter is analyzed and validated through experimental results obtained with a prototype.

The humeral suspension technique: a novel operation for deltoid paralysis

  • de Joode, Stijn GCJ;Walbeehm, Ralf;Schotanus, Martijn GM;van Nie, Ferry A;van Rhijn, Lodewijk W;Samijo, Steven K
    • Clinics in Shoulder and Elbow
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    • 제25권3호
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    • pp.240-243
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    • 2022
  • Isolated deltoid paralysis is a rare pathology that can occur after axillary nerve injury due to shoulder trauma or infection. This condition leads to loss of deltoid function that can cause glenohumeral instability and inferior subluxation, resulting in rotator cuff muscle fatigue and pain. To establish dynamic glenohumeral stability, a novel technique was invented. Humeral suspension is achieved using a double button implant with non-resorbable high strength cords between the acromion and humeral head. This novel technique was used in two patients with isolated deltoid paralysis due to axillary nerve injury. The results indicate that the humeral suspension technique is a method that supports centralizing the humeral head and simultaneously dynamically stabilizes the glenohumeral joint. This approach yielded high patient satisfaction and reduced pain. Glenohumeral alignment was improved and remained intact 5 years postoperative. The humeral suspension technique is a promising surgical method for subluxated glenohumeral joint instability due to isolated deltoid paralysis.

흰쥐의 적출된 심장에서 심정지액의 온도가 심근보호에 미치는 영향 (The Effect of Temperature of Cardioplegic Soultion on Myocardial Protection from Ischemia - Experimental Study using Isolated Rat Heart Perfusion Technique -)

  • 김용한
    • Journal of Chest Surgery
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    • 제25권2호
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    • pp.131-136
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    • 1992
  • The effect of temperature of cardioplegic solution on myocardial preservation was studied using isolated rat heart perfusion technique. Twenty Sprague-Dawley rats, weighing 120~140gm, were pretreated with intraperitoneal injection of heparin sodium[300u/kg] and then the hearts were excised after cervical herniation 30 minutes later. The hearts were perfused in isolated working heart apparatus with oxygenated modified Tyrode solution at 37oC. After 10 minutes of non working heart perfusion, the hearts were subjected to arrest for 30 minutes by administration of 5cc cardioplegic solution at the temperature of 4oC [Group I ], 15oC [Group II], 25oC [Group III], 37oC[Group IV]. At the same time, the topical cooling of heart was performed using ice saline. After arrest, the hearts were reperfused by non working heart perfusion for 1 hour with modified Tyrode solution at 37oC. The CPK, GOT and LDH in reperfusate were measured at 5,20,40,60 minutes after start of reperfusion. With the values of those, we compared the effect of temperature of cardioplegic solution on myocardial preservation. The results were as follows; 1. The enzyme values in reperfusate were highest at 5 minute and after then declined. 2. At 5 minutes after reperfusion, the enzyme values in Group I were lower than those in other Groups. These results suggest that the cardioplegic solutions using for cardiac arrest and myocardial protection can be working better at 4oC than at any other temperature.

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Mesenteric Approach in Pancreatoduodenectomy

  • Akimasa Nakao
    • Journal of Digestive Cancer Research
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    • 제4권2호
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    • pp.77-82
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    • 2016
  • The 26th World Congress of the International Association of Surgeons, Gastroenterologists and Oncologists (IASGO) was held in Seoul, Korea from September 8 to 10, 2016. In this congress, I gave a State-of-the-Art Lecture II entitled "Mesenteric Approach in Pancreatoduodenectomy." The ideal surgery for pancreatic head cancer is isolated pancreatoduodenectomy, which involves en bloc resection using a non-touch isolation technique. My team has been developing isolated pancreatoduodenectomy for pancreatic cancer since 1981, when we developed an antithrombogenic bypass catheter for the portal vein. In this operation, the first and most important step is the use of a mesenteric approach instead of Kocher's maneuver. The mesenteric approach allows dissection from the non-cancer infiltrating side and determination of cancer-free margins and resectability, followed by systematic lymphadenectomy around the superior mesenteric artery. This approach enables early ligation of the inferior pancreatoduodenal artery and total mesopancreas excision. It is the ideal surgery for pancreatic head cancer from both oncological and surgical viewpoints. The precise surgical techniques of the mesenteric approach are herein described.

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역병의 감염 여부에 따른 토양 내 진균 분포 (Analysis of Soil mycoflora in Phytophthora Infested and Non-Infested Fields)

  • 이선주;김종식;홍승범
    • 한국토양비료학회지
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    • 제33권2호
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    • pp.121-126
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    • 2000
  • 불건전 토양과 건전 토양의 환경을 이해하기 위해 자연적으로 역병에 감염되거나 감염되지 않은 고추와 토마토 시설재배지의 비근권토양, 근권토양, 근면을 채취하고 연구하였다. 시료는 경상남도의 시설재배지에서 1999년 4월에 채집되었으며, 진균의 분리는 희석평판법을 이용하였다. 각 작물 별 재배지에서 25 종의 진균이 분리되었으며 건전 시료보다는 감염 시료에서, 근권이나 근면토양보다 비근권토양에서 더 많은 수의 종이 분리되었다. 역병이 감염되지 않은 시료에서만 Trichoderma sp.가 분리되었으며 각 작물의 서식지별로 분리된 진균의 수는 다양하였다.

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Seismic control of concrete rectangular tanks subjected to bi-directional excitation using base isolation, considering fluid-structure-soil interaction

  • Mohammad Hossein Aghashiri;Shamsedin Hashemi;Mohammad Reza Kianoush
    • Structural Engineering and Mechanics
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    • 제92권1호
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    • pp.25-52
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    • 2024
  • In the current paper, the various responses of concrete rectangular liquid storage containers under seismic load, each isolated by a lead-rubber bearing subjected to bi-directional earthquake forces are investigated. A parametric study is conducted to investigate the effects of isolation period, yield strength of the isolator and the effects of soil-foundation interaction for non-isolated and base-isolated tanks located on different soil types. In most cases, the value of base shear, base moment, wall displacement and hydrodynamic pressure is reduced by the effect of the isolators whose effective frequency is within the appropriate range. The sloshing displacement is amplified due to seismic isolation of the tanks for both tall and shallow tank configurations. Also, it is found that the seismic isolation technique is more efficient for the more flexible tank. Studying various soil types indicates that, unlike the responses of non-isolated tanks which change drastically for different soil types, the responses of base-isolated structures are less affected. Finally, it is observed that the variation in structural responses is not only related to the superstructure configuration and bearings properties but also depends on the earthquake specifications.

Modelling the dispersion of a tracer gas in the wake of an isolated low-rise building

  • Quinn, A.D.;Wilson, M.;Reynolds, A.M.;Couling, S.B.;Hoxey, R.P.
    • Wind and Structures
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    • 제4권1호
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    • pp.31-44
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    • 2001
  • Mean concentrations of ammonia gas released as a tracer from an isolated low-rise building have been measured and predicted. Predictions were calculated using computational fluid dynamics (CFD) and two dispersion models: a diffusion model and a Lagrangian particle tracking technique. Explicit account was taken of the natural variation of wind direction by a technique based on the weighted summation of individual steady state wind direction results according to the probability density function of the wind direction. The results indicated that at distances >3 building heights downstream the weighted predictions from either model are satisfactory but that in the near wake the diffusion model is less successful. Weighted solutions give significantly improved predictions over unweighted results. Lack of plume spread is identified as the main cause of inaccuracies in predictions and this is linked to inadequate resolution of flow features and mixing in the CFD model. Further work on non-steady state simulation of wake flows for dispersion studies is recommended.

히스토그램 처리방법에 의한 잡음 스펙트럼 추정을 이용한 잡음환경에서의 음성인식 (Speech Recognition in Noisy Environments using the NOise Spectrum Estimation based on the Histogram Technique)

  • 권영욱;김형순
    • 한국음향학회지
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    • 제16권5호
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    • pp.68-75
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    • 1997
  • 스펙트럼 차감법은 잡음이 더해진 환경에서의 음성인시기에 널리 사용되는 전처리 방법이지만, 이를 위해서는 잡음의 스펙트럼을 잘 추정할 필요가 있다. 본 논문에서는 잡음 스펙트럼의 추정방법으로 히스토그램 처리방법을 사용한다. 이 방법은 음성/비음성 구간의 구분을 할 필요가 없으며 서서히 변화하는 잡음의 스펙트럼도 추정할 수 있다는 점에서 여타의 잡음 추정방법에 비해 장점을 지닌다. 다양한 SNR 조건하에서 유색 가우시안 잡음 및 실제 자동차 소음을 부가시킨 음성에 대해 화자독립 고립단어 인식 실험을 수행한 결과, 히스토그램 처리방법에 기반을 둔 스펙트럼 차감법의 인식성능이 초기 비음성구간의 스펙트럼 평균을 이용한 기존의 잡음 스펙트럼 추정방법에 비해 우수한 성능을 나타내었다.

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Optimized Serological Isolation of Lung-Cancer-associated Antigens from a Yeast Surface-expressed cDNA Library

  • Kim, Min-Soo;Choi, Hye-Young;Choi, Yong-Soo;Kim, Jhin-Gook;Kim, Yong-Sung
    • Journal of Microbiology and Biotechnology
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    • 제17권6호
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    • pp.993-1001
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    • 2007
  • The technique of serological analysis of antigens by recombinant cDNA expression library (SEREX) uses autologous patient sera as a screening probe to isolate tumor-associated antigens for various tumor types. Isolation of tumor-associated antigens that are specifically reactive with patient sera, but not with normal sera, is important to avoid false-positive and autoimmunogenic antigens for the cancer immunotherapy. Here, we describe a selection methodology to isolate patient sera-specific antigens from a yeast surface-expressed cDNA library constructed from 15 patient lung tissues with non-small cell lung cancer (NSCLC). Several rounds of positive selection using patient sera alone as a screening probe isolated clones exhibiting comparable reactivity with both patient and normal sera. However, the combination of negative selection with allogeneic normal sera to remove antigens reactive with normal sera and subsequent positive selection with patient sera efficiently enriched patient sera-specific antigens. Using the selection methodology described here, we isolated 3 known and 5 unknown proteins, which have not been isolated previously, but and potentially associated with NSCLC.