• 제목/요약/키워드: internal rule

검색결과 202건 처리시간 0.027초

Study of contact melting of plate bundles by molten material in severe reactor accidents

  • J.J. Ma;W.Z. Chen;H.G. Xiao
    • Nuclear Engineering and Technology
    • /
    • 제55권11호
    • /
    • pp.4266-4273
    • /
    • 2023
  • In a severe reactor accident, a crust will form on the surface of the molten material during the core melting process. The crust will have a contact melting with the internal components of the reactor. In this paper, the contact melting process of the molten material on the austenitic stainless steel plate bundles is studied. The contact melting model of parabolic molten material on the plate bundles is proposed, and the rule and main effect factors of the contact melting are analyzed. The results show that the melting velocity is proportional to the slope of the paraboloid, the heat flux and the distance between two plates D. The influence of melt gravity and the plate width on melting velocity is negligible. The thickness of the molten liquid film is proportional to the heat flux and plate width, and it is inversely proportional to the gravity. With the increase of D, the liquid film thickness decreases at first and then increases gradually. The liquid film thickness has a minimum against D. When the width of the plate is small, the width of the plate is the main factor affecting the thickness of the liquid film. The parameters are coupled with each other. In a severe reactor accident, the wider internal components of reactor, which can increase the thickness of the melting liquid film and reduce the net input heat flux from the molten material to the components, are the effective measures to delay the melting process.

원발성 폐 융모막암종 1예 (A Case of Primary Choriocarcinoma of the Lung)

  • 조영재;이세원;이상민;임재준;유철규;한성구;심영수;김영환
    • Tuberculosis and Respiratory Diseases
    • /
    • 제61권6호
    • /
    • pp.578-584
    • /
    • 2006
  • 저자들은 뚜렷한 종양성 병변이 방사선학적으로는 물론 전신 PET에서도 유일하게 폐에서만 발견이 되었고, 산부인과적 검진 및 골반 MRI 검사에서도 원발성 종양을 의심할만한 병변이 발견되지 않았으며, 병리학적으로 면역조직화학염색을 통해 ${\beta}$-HCG에 양성인 원발성 폐 융모막암종의 증례를 경험하였기에 이 환자의 임상적 소견과 경과를 문헌 고찰과 함께 보고하는 바이다.

합곡(合谷)(LI4), 태충(太衝)(Liv3) 자침(刺鍼)이 정신적 스트레스를 가한 정상 성인의 심박변이도에 미치는 영향 (Effects of LI4, Liv3 Acupuncture for Mental Stress on Short-term Analysis of Heart Rate Variability)

  • 박은영;장정아;김현진;한효정;안태한;김진원;서호석;김진이;이진환
    • 동의신경정신과학회지
    • /
    • 제21권4호
    • /
    • pp.163-173
    • /
    • 2010
  • Objectives : The objective of this study was to assess the effects of acupuncture applied at 114 and Liv3 points on heart rate variability (HRV) in normal subjects under mental stress. Methods: 36 healthy male and female subjects were recruited and randomized to a treatment group(18 subjects) or a control group (18 subjects). After 10-minutes rest period and instrumentation, both groups performed a mental stress test(Stroop color word test, Arithmetic test. four rule of arithmetic task) for l6-minutes. HRV was recorded before and after the mental stress. And then acupuncture needles were inserted on 114 and Liv3 for the study group. In the control group, they rested for l5-minutes. And Heart rate variability(HRV) was measured. Results: In the both groups, low frequency(LF) power, normalized low frequency power(LF(norm)) and ratio of low frequency to high frequency(LF/HF) was significantly increased after mental stress. Acupuncture induced significant decrease in low frequency(LF) power, normalized low frequency power(LF(norm)) and ratio of low frequency to high frequency (LF/HF) which was increased after mental stress test. In contrast, control group induced no changes. Conclusions : Acupuncture on 114 and Liv3 could be useful to decrease sympathetic activity and prevent the alteration of autonomic nervous system due to mental stress.

홍수시 댐 운영방안을 내부 경계조건으로 포함하는 부정류 계산모형 (Unsteady Flow Model Including a Dam Operation Rule for Flood Control as Internal Boundary Condition)

  • 유명관;전경수
    • 한국수자원학회논문집
    • /
    • 제37권12호
    • /
    • pp.1043-1054
    • /
    • 2004
  • 다양한 내부경계를 포함하는 폐합형 하천수계에 대한 부정류 계산모형을 개발하였다. 계산모형은 폐합형 수계모형으로서, 계산기법으로는 Preissmann의 4점 음해법과 폐합형 double sweep 알고리즘에 근거한 모형을 사용하였다. 또한 댐 및 수중보 등의 수공구조물에서 발생할 수 있는 월류흐름, 오리피스형 흐름 등에 대한 모의가 가능하도록 하고, Auto ROM에 의한 댐에서의 홍수조절 방안을 내부경계 조건으로 포함하여 홍수시 운영조건에 대한 모의가 가능하도록 하였다. 팔당댐 하류부와 충주 조정지댐 하류의 남한강 구간 및 화천댐 하류의 북한강 구간을 포함하도록 한강 수계에 대한 계산모형을 수립하였다. 또한 과거에 발생한 총 11개의 홍수사상을 사용하여 남한강 구간에 대한 조도계수를 추정하였다. 홍수기간 중 목표수위를 유지하도록 하는 팔당댐 및 북한강 수계 댐들의 홍수조절 방안을 설정하고, 수립된 방법을 사용하여 과거에 발생한 홍수사상에 대한 모의계산을 수행한 결과, 설정된 홍수조절 방안이 잘 모의되는 것으로 나타났다.

간스캔의 ROC분석에 의한 진단적 평가 (ROC Analysis of Diagnostie Performance in Liver Scan)

  • 이명철;문대혁;고창순;송본철;관야지남
    • 대한핵의학회지
    • /
    • 제22권1호
    • /
    • pp.39-45
    • /
    • 1988
  • To evaluate diagnostic accuracy of liver scintigraphy we analysed liver scans of 143 normal and 258 patients with various liver diseases. Three ROC curves for SOL, liver cirrhosis and diffuse liver disease were fitted using rating methods and areas under the ROC curves and their standard errors were calculated by the trapezoidal rule and the variance of the Wilcoxon statistic suggested by McNeil. We compared these results with that of National Institute of Radiological Science in Japan. 1) The sensitivity of liver scintigraphy was 74.2% in SOL, 71.8% in liver cirrhosis and 34.0% in diffuse liver disease. The specificity was 96.0% in SOL, 94.2% in liver cirrhosis and 87.6% in diffuse liver diasease. 2) ROC curves of SOL and liver cirrhosis approached the upper left-hand corner closer than that of diffuse liver disease. Area (${\pm}$ standard error). under the ROC curve was $0.868{\pm}0.024$ in SOL and $0.867{\pm}0.028$ in liver cirrhosis. These were significantly higher than $0.658{\pm}0.043$ in diffuse liver disease. 3) There was no interobserver difference in terms of ROC curves. But low sensitivty and high specificity of authors' SOL diagnosis suggested we used more strict decision threshold.

  • PDF

전자상거래 통합을 위한 XML 매핑 정형화 기법 (A Method of XML Mapping Canonicalization for E-Business Integration)

  • 안우영;홍창범
    • 한국컴퓨터정보학회논문지
    • /
    • 제9권1호
    • /
    • pp.1-8
    • /
    • 2004
  • XML을 핵심 기술로 사용하는 RosettaNet이나 BizTalk 등의 다양한 전자상거래 프레임워크들이 생겨나기 시작하면서 프레임워즈들은 각자의 표준에 따라 파트너간에 비즈니스 프로세스를 수행하게 된다. 이러한 프레임워크간의 상이함은 전자상거래시 기업 간의 문서의 다양성으로 인하여 문서 교환에 어려움이 따르게 된다. 본 논문에서는 XML문서의 정보를 추출 단계를 거쳐 문서정보를 기반으로 매핑 정보를 생성한 후 문서간의 매핑룰을 적용하여 변환할 수 있도록 설계하였다. 따라서 전자상거래 프레임워크 간 정보의 손실 없이 상호 문서 교환이 가능할 뿐만 아니라 신뢰할 수 있는 교환이 가능하다.

  • PDF

Paradoxical Transtentorial Herniation Caused by Lumbar Puncture after Decompressive Craniectomy

  • Jung, Heyun-Jin;Kim, Dong-Min;Kim, Seok-Won
    • Journal of Korean Neurosurgical Society
    • /
    • 제51권2호
    • /
    • pp.102-104
    • /
    • 2012
  • Although decompressive craniectomy is an effective treatment for various situations of increased intracranial pressure, it may be accompanied by several complications. Paradoxical herniation is known as a rare complication of lumbar puncture in patients with decompressive craniectomy. A 38-year-old man underwent decompressive craniectomy for severe brain swelling. He remained neurologically stable for five weeks, but then showed mental deterioration right after a lumbar puncture which was performed to rule out meningitis. A brain computed tomographic scan revealed a marked midline shift. The patient responded to the Trendelenburg position and intravenous fluids, and he achieved full neurologic recovery after successive cranioplasty. The authors discuss the possible mechanism of this rare case with a review of the literature.

Fuzzy 추론을 이용한 3상 전력용 변압기 보호계전 알고리즘 (3 phase Power Transformer Protective Relaying Algorithm based on Fuzzy Inference)

  • 김상태;진보건;정상기;이승재;강상희;윤상현;이상윤
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 하계학술대회 논문집 A
    • /
    • pp.197-199
    • /
    • 2000
  • The various criteria to identify the disturbances of the power transformer has been reported in this paper. They have been derived through EMTP simulations of internal faults, inrush and overexcitation for the model of 154/22.9[kV], 40[MVA], Y-Y three-phase power transformer. We also propose the algorithm which makes bpa Functions and infers the final decision from them based on Modfied Dempster-Shafer's rule of combination.

  • PDF

Diffuse Alveolar Hemorrhage

  • Park, Moo Suk
    • Tuberculosis and Respiratory Diseases
    • /
    • 제74권4호
    • /
    • pp.151-162
    • /
    • 2013
  • Diffuse alveolar hemorrhage (DAH) is a life-threatening and medical emergency that can be caused by numerous disorders and presents with hemoptysis, anemia, and diffuse alveolar infiltrates. Early bronchoscopy with bronchoalveolar lavage is usually required to confirm the diagnosis and rule out infection. Most cases of DAH are caused by capillaritis associated with systemic autoimmune diseases such as anti-neutrophil cytoplasmic antibody-associated vasculitis, anti-glomerular basement membrane disease, and systemic lupus erythematosus, but DAH may also result from coagulation disorders, drugs, inhaled toxins, or transplantation. The diagnosis of DAH relies on clinical suspicion combined with laboratory, radiologic, and pathologic findings. Early recognition is crucial, because prompt diagnosis and treatment is necessary for survival. Corticosteroids and immunosuppressive agents remain the gold standard. In patients with DAH, biopsy of involved sites can help to identify the cause and to direct therapy. This article aims to provide a general review of the causes and clinical presentation of DAH and to recommend a diagnostic approach and a management plan for the most common causes.

준측지궤적 알고리즘을 적용한 내압을 받는 필라멘트 와인딩 된 복합재 축대칭 구조물의 최적설계 (Optimal Design of Filament Wound Structures under Internal Pressure based on the Semi-geodesic Path Algorithm)

  • 김철웅;강지호;홍창선;김천곤
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2003년도 추계학술발표대회 논문집
    • /
    • pp.179-182
    • /
    • 2003
  • This research aims to establish an optimal design method of filament wound structures. So far, most design and manufacturing of filament wound structures have been based on manufacturing experiences, and there is no established design rule. In this research, possible winding patterns considering the windability and the slippage between fiber and mandrel surface were calculated using the semi-geodesic path algorithm. In addition, finite element analyses using a commercial code, ABAQUS, were performed to predict the behavior of filament wound structures. On the basis of the semi-geodesic path algorithm and the finite element analysis method, filament wound structures were designed using the genetic algorithm.

  • PDF