• Title/Summary/Keyword: Operation history

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A Temporal Relational Database:Modeling and Language

  • Kim, Jae-Kyeong
    • Journal of the Korean Operations Research and Management Science Society
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    • v.20 no.2
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    • pp.139-158
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    • 1995
  • A temporal database systems provides timing information and maintains history of data compared to the conventional database system. In this paper, we present a temporal relational database which use an interval-stamping method for instant-based events and for interval-based states. A set of temporal algebraic operators are developed on an instance of time and interval of time so that we can manipulate events and states at a same time. The set of operation is the basis for creating a relational algebra that is closed for temporal relations. And temporal SQL is also suggested as a temporal query relational language for our algebraic operations on temporal relations.

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2D genus topology of 21-cm differential brightness temperature during cosmic reionization

  • Ahn, Kyung-Jin
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.46.2-46.2
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    • 2011
  • Planck is already in active operation, and in a few years a detailed CMB anisotropy map will be compiled, surpassing WMAP both in temperature and polarization. The E mode - E mode autocorrelation power spectrum at large scales contains weak but sizable information on the history of cosmic reionization. We show our latest advance of our own simulation of cosmic reionization that incorporates Pop III stars, and provide a forecast for Planck polarization measurement.

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Surgical Treatment of Thoracic Outlet Syndrome (흉곽 출구 증후군 수술치험 1례)

  • 서정욱
    • Journal of Chest Surgery
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    • v.27 no.6
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    • pp.506-508
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    • 1994
  • Thoracic outlet syndrome refers to compression of the subclavian vessels and brachial plexus at the superior aperture of the thorax. A 35-year old female was evaluated for right hand numbness. This patient had a history of headache, right shoulder pain, and right hand numbness during 10 months.Preoperative angiography, EMG, and NCV was performed. First rib and cervical rib resection was done with transaxillary approach. After operation, right hand numbness and right shoulder pain were disappeared. Postoperative course was uneventful.

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Analysis on Factors Influencing on Wind Power Generation Using LSTM (LSTM을 활용한 풍력발전예측에 영향을 미치는 요인분석)

  • Lee, Song-Keun;Choi, Joonyoung
    • KEPCO Journal on Electric Power and Energy
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    • v.6 no.4
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    • pp.433-438
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    • 2020
  • Accurate forecasting of wind power is important for grid operation. Wind power has intermittent and nonlinear characteristics, which increases the uncertainty in wind power generation. In order to accurately predict wind power generation with high uncertainty, it is necessary to analyze the factors affecting wind power generation. In this paper, 6 factors out of 11 are selected for more accurate wind power generation forecast. These are wind speed, sine value of wind direction, cosine value of wind direction, local pressure, ground temperature, and history data of wind power generated.

Surgical Management of Chronic Pulmonary Embolism - Surgical treatment and perioperative problems - (만성 페색전증의 외과적 요법수술 및 수술 전후 문제)

  • 김응수
    • Journal of Chest Surgery
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    • v.20 no.1
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    • pp.139-147
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    • 1987
  • in general rapid and complete resolution of pulmonary emboli, even massive, is the natural history. However, rarely, the emboli do not resolve but rather became fibrotic organization and densely adherent to the arterial wall, therefore, may lead to significant clinical disability. In patients with chronic pulmonary embolism, medical management usually has little effect and only surgical treatment can offer improvement. The case was 30-year-old man who had admission to the Hanyang University Hospital due to fall-down from 11th floor 407 days before operation and then transferred to our department for surgical management under the diagnosis of chronic pulmonary embolism, Pulmonary angiogram demonstrated multifocal thromboembolism with infarction and lung scans showed no improvement in spite of anticoagulant and thrombolytic therapy. At median sternotomy for pulmonary artery thromboembolectomy, the well organized and multiple septic emboli could be removed by gallstone forceps. But reoperation of left upper lobectomy was performed because of the repeated hemoptysis and suspicious pulmonary arterio-bronchial fistula 19 days postoperatively. Despite of ventilatory support and drug treatment, the patient died due to right heart failure associated with cor pulmonale 27 days after first operation. Discussion of the operative and perioperative problems are offered.

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Tracheal Rupture Following Double-lumen Endotracheal Tube Intubation -One Case Report- (이중관 기관 삽관후 발생된 기관파열 - 1례 보고 -)

  • 박승일;원준호;이종국
    • Journal of Chest Surgery
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    • v.32 no.8
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    • pp.765-767
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    • 1999
  • Tracheobronchial rupture following tracheal intubation is a rare complication. We experienced a case of tracheal rupture following double-lumen endotracheal tube intubation. A 76 year old female was admitted due to coughing and chest discomfort. The operation was performed with the diagnosis of congenital broncho esophageal fistula. During the operation, accidently the main trachea was ruptured longitudinally. There was no history of surgical trauma. The ruptured trachea was repaired with prolene and monofilament absorbable sutures. The cause of tracheal rupture was suspected overinflation of the cuff. The patient was discharged from the hospital without any significant complications.

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Vertebral Metastasis from Hepatocellular Carcinoma of Unknown Origin

  • Kim, Young-Jin;Kim, Sung-Bum;Yi, Hyeong-Joong;Kim, Hyuk
    • Journal of Korean Neurosurgical Society
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    • v.40 no.1
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    • pp.47-50
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    • 2006
  • This 51-year-old man suffered from paraparesis of 1-week history. On preoperative images, spinal cord compression by infiltrative vertebral mass was shown at T3 and T4 level. Several months earlier, he underwent surgical resection of left 2nd to 4th ribs, due to painful growing chest wall mass, which was proved to be hepatocellular carcinoma. All available diagnostic procedure failed to uncover origin of malignancy. Operation was followed by adjuvant irradiation and chemotherapy to the vertebral mass, however he only to die in 3 months after operation. This is an extremely rare case of ectopic hepatocellular carcinoma at thoracic vertebrae which showed very aggressive clinical course. Possible pathogenic process is presented and discussed.

Giant Atherosclerotic Aneurysm of Common Femoral Artery (총대퇴동맥의 동맥경화성 거대 동맥류 -1례 보고-)

  • 장인석;김성호
    • Journal of Chest Surgery
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    • v.29 no.10
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    • pp.1157-1159
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    • 1996
  • Atherosclerotic giant aneurysm of the common femoral artery is rare. Because the patients who lose timing of the operation face amputation or death, the surgical treatment must be performed at the proper time. A 72-old man was admitted to the hospital because of a 20-days history of pulsatile growing mass on his left groin. After the diagnosis of giant aneurysm of the common femoral artery by computerized tomography and digital subtraction angiography, an emergent operation was performed. Both deep and superficial femoral arteries were successfully reconstructed with Gore-tex grafts after aneurysmectomy. The pathology of the aneurysm was proved to be atherosclerosis.

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Dynamic Filtering of End-milling Force Using Wavelet Filter Bank (웨이블렛 필터뱅크를 이용한 동적 엔드밀 절삭력 필터링)

  • Cho, Hee-Geun;Chin, Do-Hun;Yoon, Moon-Chul
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.18 no.4
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    • pp.381-387
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    • 2009
  • The end-milling force behaviour is very complex and it is related to a de-noising phenomenon, so it is very difficult to detect and diagnose this static cutting force phenomenon. This paper presents a new method of filtering of end-milling force in end-milling operation using filter bank technique, based on the wavelet transform. In this paper by comparing the history of end-milling force using wavelet filtering the fundamental end-milling property of the wavelet transform is well reviewed and analyzed. This result of wavelet transform using filter bank shows the possible static prediction of end-milling force with severe dynamic properties such as chatter in end-milling operation.

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