• Title/Summary/Keyword: Dead Space

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The clinical study of pulmonary aspergillosis -A report of 14 cases- (폐 Aspergillosis 14 예 보고)

  • 박철호
    • Journal of Chest Surgery
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    • v.19 no.4
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    • pp.715-721
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    • 1986
  • 14 cases of pulmonary aspergillosis were managed surgically over a 6 year period in the Dept. of Thoracic Surgery Inje Medical College, Paik Hospital were reviewed. 1. Male, female ratio was 9:5 male predominant and 2,3,4 decade were prevalent. 2. The most prevalent chief complaint was hemoptysis, 9 cases [63%] and other symptoms were chronic productive cough 4 cases. 3. Preoperative diagnostic accuracy ratio was 0.21 [3 cases only]. 4. Right upper lobe was most common involving site, 7 cases [5[%], 13 lobectomy and 2 segmentectomy were performed. 5. Pathological underlying diseases were pulmonary tuberculosis 8 cases [57%], bronchiectasis and lung abscess was 1 case, no underlying disease were 4 cases. 6. One major postoperative complication was symptomatic residual dead space which was managed by thoracoplasty.

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SVPWM System for Induction Motor Drive Using ASIC (ASIC을 이용한 유도전동기 구동용 SVPWM 시스템)

  • Lim, Tae-Yun;Kim, Dong-Hee;Kim, Jong-Moo;Kim, Joong-Ki;Kim, Min-Heui
    • Journal of the Korean Society of Industry Convergence
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    • v.2 no.2
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    • pp.103-108
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    • 1999
  • The paper describes a implementation of space vector pulse-width modulation voltage source inverter and interfacing of DSP using field programmable gate array(FPGA) for a induction motor vector control system. The implemented chip is included logic circuits for SVPWM, dead time compensation and speed detection using Quick Logic, QLl6X24B. The maximum operating frequency and delay time can be set to 110MHz and 6 nsec. The designed Application Specific Integrated Circuit(ASIC) for SVPWM can be incorporated with a digital signal processing to provide a simple and effective solution for high performance induction motor drives with a voltage source inverter. Simulation and implementation results are shown to verify the usefulness of ASIC in a motor drive system and power electronics applications.

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Primary pulmonary adenocarcinoma metastasized to kidney in a captive nutria (Myocastor coypus)

  • Oh, Yeonsu;Cho, Ho-Seong
    • Korean Journal of Veterinary Service
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    • v.40 no.2
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    • pp.139-142
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    • 2017
  • A six-year-old male captive nutria (Myocastor coypus) maintained in a closed space with a small vent was found dead in his cage. Gross findings showed multifocal nodules in varying sizes, small 0.5 to large 5 cm in diameter, intermixed with normal parenchyma were scattered all over the surface of the lungs and a kidney, which the cut surface was smooth, compact and whitish in color. Microscopically, small round to oval neoplastic cells with modest to slight amounts of cytoplasm formed acinar and gland-like structures. Immunohistochemically, cells were strongly positive for E-cadherin and slightly reactive for thyroid transcription factor-1 (TTF-1). Based on those diagnostic features, the neoplasia was diagnosed as primary pulmonary adenocarcinoma (small cell type) and metastasized into the kidney. This is the first case report of malignant pulmonary tumor and its metastasis in the nutria.

High-flow nasal cannula oxygen therapy in children: a clinical review

  • Kwon, Ji-Won
    • Clinical and Experimental Pediatrics
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    • v.63 no.1
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    • pp.3-7
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    • 2020
  • High-flow nasal cannula (HFNC) is a relatively safe and effective noninvasive ventilation method that was recently accepted as a treatment option for acute respiratory support before endotracheal intubation or invasive ventilation. The action mechanism of HFNC includes a decrease in nasopharyngeal resistance, washout of dead space, reduction in inflow of ambient air, and an increase in airway pressure. In preterm infants, HFNC can be used to prevent reintubation and initial noninvasive respiratory support after birth. In children, flow level adjustments are crucial considering their maximal efficacy and complications. Randomized controlled studies suggest that HFNC can be used in cases of moderate to severe bronchiolitis upon initial low-flow oxygen failure. HFNC can also reduce intubation and mechanical ventilation in children with respiratory failure. Several observational studies have shown that HFNC can be beneficial in acute asthma and other respiratory distress. Multicenter randomized studies are warranted to determine the feasibility and adherence of HFNC and continuous positive airway pressure in pediatric intensive care units. The development of clinical guidelines for HFNC, including flow settings, indications, and contraindications, device management, efficacy identification, and safety issues are needed, particularly in children.

IMPLANTATION OF TOOTHASH COMBINED WITH PLASTER OF PARIS;CLINICAL APPLICATIONS (치아회분말과 치과용 연석고의 혼합매식술;임상적 적용)

  • Kim, Young-Kyun;Yeo, Hwan-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.16 no.2
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    • pp.130-136
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    • 1994
  • Toothash and plaster of Paris (Calcium sulfate) have been studied for bone substitute through experimental studies and clinical studies. Toothash is like resorbable hydroxyapatite. Plaster of Paris is resorbable and biocompatible. The toothash combined with plaster of Paris has the advantages of individual characteristics. The authors used this composite material in the jaw defect filling. In operation, we could manage this implant material easily and remove the dead space. During the followup period, this composite material was resorbed gradually and substituted as new-forming bone from the surrounding tissue. Complications were minor and treated completely without problems.

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Study of a SEPIC-input Self-driven Active Clamp ZVS Converter

  • Cao, Guo-En;Kim, Hee-Jun
    • Journal of international Conference on Electrical Machines and Systems
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    • v.2 no.2
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    • pp.202-215
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    • 2013
  • This paper proposes a SEPIC-input, self-driven, active clamp ZVS converter, where an auxiliary winding and a RC delay circuit are employed to drive the active clamp switch and to achieve asymmetrical duty control without any other extra circuits. Based on the fixed dead time and the resonance between capacitors and inductors, both the main switch and the auxiliary switch can rule the ZVS operation. Detailed operation modes are presented to illustrate the self-driven and ZVS principles. Furthermore, an accurate state-space model and the transfer functions of the proposed converter have been presented and analyzed in order to optimize dynamic performance. The model provides efficient prediction of converter operations. Experimental results, based on a prototype with 80V input and 15V/20A output, are discussed to verify the transient and steady performance of the proposed converter.

A Case of Tracheostomy Cannula Inserted in the Trachea for 10 Years (10년간 기관에 삽관되어 있었던 기관 절개관 1례)

  • 김중환;오경균;정완교;이상기;김정배;길동석;서정하
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1983.05a
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    • pp.5.4-6
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    • 1983
  • A tracheostomy is performed to relieve an upper airway obstruction, to facilitate bronchial toilet, to decrease dead space, to assist ventilation and as an elective procedure in head and neck surgery. Many complications are associated with tracheostomy, both in the actual performance of the operation and in the postoperative management. Recently the authors report one case ; a two years old children got a severe burn on face and neck and received tracheostomy and have carried tracheostomy cannula for 10 years, at last the cannula was worn out and the 12 years old boy came to the hospital.

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The fabrication of micro mass flow sensor by Micro-machining Technology (Micromachining 기술을 이용한 micro mass flow sensor의 제작)

  • Eoh, Soo-Hae;Choi, Se-Gon
    • Proceedings of the KIEE Conference
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    • 1987.07a
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    • pp.481-485
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    • 1987
  • The fabrication of a micro mass flow sensor on a silicon chip by means of micro-machining technology is described on this paper. The operation of micro mass flow sensor is based on the heat transfer from a heated chip to a fluid. The temperature differences on the chip is a measure for the flow velocity in a plane parallel with the chip surface. An anisotropic etching technigue was used for the formation of the V-type groove in this fabrication. The micro mass flow sensor is made up of two main parts ; A thin glass plate embodying the connecting parts and mass flow sensor parts in silicon chip. This sensor have a very small size and a neglible dead space. Micro mass flow sensor can fabricate on silicon chip by micro machining technology too.

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Splitting policies based on clustering trajectories for indexing positions of moving objects (이동체의 위치 색인을 위한 궤적 클러스터링 기반의 분할 정책)

  • 김진곤;전봉기;홍봉희
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04a
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    • pp.773-775
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    • 2003
  • 이동성을 갖는 장치들의 위치 정보를 관리하기 위하여 이동체 데이터베이스에 관한 연구가 필요하게 되었다. 이동체 색인의 검색에서 영역 질의와 궤적 질의는 공간 근접성과 궤적 연결성과 같이 상반된 특징으로 인하여 함께 고려되지 않았다. 이동체 색인에서 영역 질의의 성능개선을 위해서는 노드간의 심한 중복과 사장 공간(Dead space)을 줄여야 하고, 궤적 질의의 성능 개선을 위해서는 이동체의 궤적 보전이 이루어져야 한다. 이와 같은 요구 조건을 만족하기 위해, 이 논문에서는 R-tree를 기반의 색인 구조에서 새로운 분할 정책을 제안한다. 제시하는 색인 구조에서 단말 노드의 엔트리는 궤적이며, 비단말 노드의 엔트리는 자식 노드이다. 단말 노드 분할 정책에서 동일 궤적을 그룹화해서 분할 하는 공간 축 분할 정책과 공간 활용도를 높이는 시간 축 분할 정책을 제안한다. 시간 축 분할 후 사장영역이 클 경우에는 다중 분할을 수행하여 사장 공간을 줄이고 노드간의 중복을 최소화한다. 비 단말 노드 분할 정책에서는 같은 궤적을 저장하는 노드들을 연결 노드(Connected Node)라고 정의하고, 엔트리의 궤적 연결성을 기준으로 분할한다.

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Nearest Neighbor Query Processing for Moving object (이동 객체에 대한 최근접 질의처리)

  • 강혜영;김경숙;이기준
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10a
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    • pp.190-192
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    • 2001
  • 시간에 따라 공간적 위치가 연속적으로 변하는 객체를 이동객체라 한다. 이동객체에 대한 최근접 질의는 시간에 따라 거리도 달라지게 됨으로써 기존의 방법을 그대로 이용하기 어렵다. 본 논문에서는 이동객체에 대한 최근접 질의를 3D R-tree를 이용한 최근접 탐색방법에 시간적 요소를 추가하여 처리하였다. 또, 3D R-tree를 구성하는 노드의 크기에 따른 사장공간(Dead Space)이 최근접 질의에 미치는 영향을 분석하였다. 실험결과에 따르면 이동객체를 하나의 노드에 저장하면 사장공간이 증가하여 불필요한 노드를 접근함으로써 성능이 떨어지고 여러 개로 분할하여 저장하게 되면 색인의 크기가 커짐으로써 질의 처리 성능이 떨어지게 된다. 따라서, 이동객체에 대한 적절한 분할 및 병합 정책이 필요하다는 것을 알 수 있다.

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