• 제목/요약/키워드: extensive stage

검색결과 319건 처리시간 0.021초

필름 Capacitor의 전기적Damage에 관한 연구 (electrical Damage of Metallized Film Capacitors)

  • 서광석
    • 대한전기학회논문지
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    • 제40권6호
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    • pp.574-581
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    • 1991
  • Damage in film capacitors has been investigated, using FTIR and ESCA, aiming to elucidate the nature of electrode removal and the possibility of base films to be damaged. Also, tests were conducted to investigate the effect of a long-term thermal aging at elevated temperatures. Unsuccessful clearing or grape-clustering processes can induce a long-term degradation which involves the chemical and morphological changes. Major changes are the oxidation and the decrease in surface crystallinity possibly arising from the corona discharge. An immediate deterioration of BOPP film may occur when the air entrapped between the film layers induces an extensive autocatalytic oxidative degradation. This type of immediate damage may result in a premature failure at an early stage of qualification test. As far as the nature of electrode removal is concerned, a permanent removal of electrode materials was observed in the main erosion area.

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Robust 제어기를 이용한 발전 여자 시스템 전력 안정도 개선 (PSS Improvement of Generator Excitation System using Robust Controller)

  • 홍현문;최재호;류홍우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 A
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    • pp.364-367
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    • 1996
  • This paper deals with the design and evaluation of the robust controller for generator excitation system to improve the steady state and transient stabilities. The nonlinear characteristics of the system is treated as model uncertainties, and then the robust control techniques are introduced into the PSS design to take into account these uncertainties at the controller design stage. The performance of the designed controller is examined by extensive non-linear time domain simulation. It is shown that the performance of the robust controller is superior to that of the conventional PSS in all cases studied.

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Toxicoinformatics: The Master Key for Toxicogenomics

  • Lee, Wan-Sun;Kim, Yang-Seok
    • Molecular & Cellular Toxicology
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    • 제1권1호
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    • pp.13-16
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    • 2005
  • The current vision of toxicogenomics is the development of methods or platforms to predict toxicity of un characterized chemicals by using '-omics' information in pre-clinical stage. Because each chemical has different ADME (absorption, distribution, mechanism, excretion) and experimental animals have lots of variation, precise prediction of chemical's toxicity based on '-omics' information and toxicity data of known chemicals is very difficult problem. So, the importance of bioinformatics is more emphasized on toxicogenomics than other functional genomics studies because these problems can not be solved only with experiments. Thus, toxicoinformatics covers all information-based analytical methods from gene expression (bioinformatics) to chemical structures (cheminformatics) and it also deals with the integration of wide range of experimental data for further extensive analyses. In this review, the overall strategy to toxicoinformatics is discussed.

선천성 심기형에 동반된 누두흉에서 동시에 시행안 심기형 교정 및 Nuss 수술 -1예 보고- (Nuss Operation with Simultaneous Intracardiac Repair -A case report-)

  • 허재학;장지민;김욱성;장우익;정철현
    • Journal of Chest Surgery
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    • 제37권6호
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    • pp.536-538
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    • 2004
  • 선천성 심기형과 흉벽기형이 동반되어 있는 경우 이 두 질환을 동시에 수술하는 경우에 변형된 늑연골의 광범위한 절제에 따른 합병증이 단점으로 지적되고 있다. 본원 흉부외과에서는 부분 방실중격 결손증과 오목가슴이 동반된 8세 환아에서 개심술 시에 Nuss 술식을 이용하여 오목가슴을 교정함으로써 광범위한 늑골절제에 따른 수술시간의 지연이나 출혈, 흉벽의 불안정성 등의 단점없이 좋은 결과를 얻었기에 이를 보고하는 바이다.

Craniovertebral Junction Tuberculosis with Atlantoaxial Dislocation : A Case Report and Review of the Literature

  • Lee, Dae-Kyu;Cho, Keun-Tae;Im, So-Hyang;Hong, Seung-Koan
    • Journal of Korean Neurosurgical Society
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    • 제42권5호
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    • pp.406-409
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    • 2007
  • Craniovertebral junction (CVJ) tuberculosis is a rare disease, potentially causing severe instability and neurological deficits. The authors present a case of CVJ tuberculosis with atlantoaxial dislocation and retropharyngeal abscess in a 28-year-old man with neck pain and quadriparesis. Radiological evaluations showed a widespread extradural lesion around the clivus, C1, and C2. Two stage operations with transoral decompression and posterior occipitocervical fusion were performed. The pathological findings confirmed the diagnosis of tuberculosis. Treatment options in CVJ tuberculosis are controversial without well-defined guidelines. But radical operation (anterior decompression and posterior fusion and fixation) is necessary in patient with neurological deficit due to cord compression, extensive bone destruction, and instability or dislocation. The diagnosis and treatment options are discussed.

Successful Treatment of Abdominal Cutaneous Entrapment Syndrome Using Ultrasound Guided Injection

  • Hong, Myong Joo;Kim, Yeon Dong;Seo, Dong Hyuk
    • The Korean Journal of Pain
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    • 제26권3호
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    • pp.291-294
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    • 2013
  • There are various origins for chronic abdominal pain. About 10-30% of patients with chronic abdominal pain have abdominal wall pain. Unfortunately, abdominal wall pain is not thought to be the first origin of chronic abdominal pain; therefore, patients usually undergo extensive examinations, including diagnostic laparoscopic surgery. Entrapment of abdominal cutaneous nerves at the muscular foramen of the rectus abdominis is a rare cause of abdominal wall pain. If abdominal wall pain is considered in earlier stage of chronic abdominal pain, unnecessary invasive procedures are not required and patients will reach symptom free condition as soon as the diagnosis is made. Here, we report a case of successful treatment of a patient with abdominal cutaneous nerve entrapment syndrome by ultrasound guided injection therapy.

UCP 600: 국제 사적 부문 자체 규제의 일례 (UCP600: An Exercise in International Private Sector Self Regulation)

  • Byrne, James E.
    • 무역상무연구
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    • 제36권
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    • pp.47-84
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    • 2007
  • The Uniform Customs and Practice for Documentary Credits ("UCP") may be treated as a useful laboratory for studying the scope and limitations of self regulation. This is due to its almost universal success on a global stage which provides it a perspective rarely available for self regulatory provisions and due to extensive experience of judicial review of it. In this sense, it is worthwhile to examine in brief the latest iteration of the UCP, Publication No. 600 ("UCP600"). This article describes and analyze some of core provisions of the UCP600 from the perspective of their adequacy as an exercise in self regulation. It is attempted first in view of several categories of private rulemaking; definitional rulemaking, default rules, procedural rules, and remedies. After that, it is examined second in view of sound rulemaking which is related to the relative role of law and practice. It points out rich and varied insights into the possibilities and problems associated with private rulemaking in connection with commercial transactions.

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전계센서의 원리를 이용한 공기중 부분방전신호 검출 (PD Detection in Air by Capacitive Electric Field Sensor)

  • 이용희;이강원;박성희;강성화;신양섭;임기조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.900-903
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    • 2002
  • Partial discharges(PD) in air, corona discharges, deteriorate the insulation strength. So, it is necessary to detect PD at an early stage before the system failure and extensive damage to the equipment. PD emit signals which can be detected by applying an capacitive electric field diagnosis. In this paper, We measured signals by capacitive electric field sensor and analyzed FFT from PD, and then compared conventional electric PD detecting method to capacitive electric field diagnosis by $\Psi-q-n$, $\Psi-v-n$, $\Psi-n$, $\Psi-q$ distributions.

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휴대폰용 초정밀 사각 밧데리 케이스의 ???K드로잉 공정설계 (Process Design for Deep Drawing of High Precision Rectangular Battery Case used in Cellular Phone)

  • 김홍주;구태완;강범수
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 추계학술대회 논문집
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    • pp.97-100
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    • 2000
  • Today deep drawing and ironing are the major process in manufacturing of battery case used in cellular phone from aluminum. The same technology is utilized in manufacturing of steel or aluminum cans for components of medical instrument, portable PC, walkman and so on. Most of these processes require multi-stage ironing following the deep drawing and redrawing processes. The practical aspects of this technology are well known and gained through extensive experiment and production know-how. However, the fundamental aspects of theses processes are relatively less known. Thus, it is expected that process simulations using FEM techniques would provide additional detailed information that could be utilized to improve the process condition. This paper illustrates the application of process modeling to deep drawing and redrawing operations for High Precision Rectangular Battery Case. A commercially avaliable finite element code LS-DYNA3D was used to simulate deep drawing and redrawing operations.

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Computational study of road tunnel exposure to severe wind conditions

  • Muhic, Simon;Mazej, Mitja
    • Wind and Structures
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    • 제19권2호
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    • pp.185-197
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    • 2014
  • Ventilation and fire safety design in road tunnels are one of the most complex issues that need to be carefully considered and analysed in the designing stage of any potential upgrade of ventilation and other fire safety systems in tunnels. Placement road tunnels space has an important influence on fire safety, especially when considering the effect of adverse wind conditions that significantly influence ventilation characteristics. The appropriate analysis of fire and smoke control is almost impossible without the use of modern simulation tools (e.g., CFD) due to a large number of influential parameters and consequently extensive data. The impact of the strong wind is briefly presented in this paper in the case of a longitudinally ventilated road tunnel Kastelec, which is exposed to various severe wind conditions that significantly influence its fire safety. The possibility of using CFD simulations in the analysis of the tunnel placement in space terms negative effect of wind influence on the tunnel ventilation is clearly indicated.