• 제목/요약/키워드: internal rule

검색결과 205건 처리시간 0.027초

A study on the working mechanism of internal pressure of super-large cooling towers based on two-way coupling between wind and rain

  • Ke, Shitang;Yu, Wenlin;Ge, Yaojun
    • Structural Engineering and Mechanics
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    • 제70권4호
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    • pp.479-497
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    • 2019
  • In the current code design, the use of a uniform internal pressure coefficient of cooling towers as internal suction cannot reflect the 3D characteristics of flow field inside the tower body with different ventilation rate of shutters. Moreover, extreme weather such as heavy rain also has a direct impact on aerodynamic force on the internal surface and changes the turbulence effect of pulsating wind. In this study, the world's tallest cooling tower under construction, which stands 210m, is taken as the research object. The algorithm for two-way coupling between wind and rain is adopted. Simulation of wind field and raindrops is performed iteratively using continuous phase and discrete phase models, respectively, under the general principles of computational fluid dynamics (CFD). Firstly, the rule of influence of 9 combinations of wind speed and rainfall intensity on the volume of wind-driven rain, additional action force of raindrops and equivalent internal pressure coefficient of the tower body is analyzed. The combination of wind velocity and rainfall intensity that is most unfavorable to the cooling tower in terms of distribution of internal pressure coefficient is identified. On this basis, the wind/rain loads, distribution of aerodynamic force and working mechanism of internal pressures of the cooling tower under the most unfavorable working condition are compared between the four ventilation rates of shutters (0%, 15%, 30% and 100%). The results show that the amount of raindrops captured by the internal surface of the tower decreases as the wind velocity increases, and increases along with the rainfall intensity and ventilation rate of the shutters. The maximum value of rain-induced pressure coefficient is 0.013. The research findings lay the basis for determining the precise values of internal surface loads of cooling tower under extreme weather conditions.

원인 불명의 급성 신부전으로 발현된 급성 파라콰트중독 1례 (A case of Diagnosing Paraquat Intoxication on Transferred Patient with Acute Renal Failure)

  • 길효욱;양종오;이은영;홍세용
    • 대한임상독성학회지
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    • 제2권1호
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    • pp.45-48
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    • 2004
  • Paraquat, a widely used herbicide, is extremely toxic, causing multiple organ failure in human. Many treatment modality has been used, but now paraquat is very fatal drug. Elimination rate of plasma paraquat seems to be a factor for the survival rate. So early diagnosis and early treatment are very important. Plasma paraquat concentration could be measured by radioimmunoassay. But it is impossible that the test was done at Emergency room and the result was checked immediately. There was relation between plasma paraquat concentrations and urine paraquat concentration. Because of its simplicity and low cost, urine paraquat concentration test is complementary to the plasma concentration measurement. If the patient has psychotic problem or unconscious mental state, and is observed unexplained dyspnea and oral ulcer, urine paraquat test is very important to rule out acute paraquat intoxication. We experienced a patient who was presented as unexplained acute renal failure initially and was diagnosed as paraquat intoxication later.

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『황제내경(黃帝內經)』의 철학적 배경에 대한 연구 - 전국(戰國) ~ 한(漢) 시대정신(時代精神)을 중심으로 - (A Study on the Philosophical Background of HuangdiNeijing - Focused on the Spirit of the Times from Warring Country to Han -)

  • 류정아
    • 대한한의학원전학회지
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    • 제30권1호
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    • pp.145-166
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    • 2017
  • Objectives : The paper aims to study the philosophical background of Huangdineijing by taking into account the fact that its ideas are identical to that of the period between the Warring States and Han. Methods : Through considering the period and the historical backdrop in which Huangdineijing was published, and through considering the book with other texts such as Huangdisijing, the paper draws the common spirit of the time and analyzed the cause and flow of philosophies and ideas that influenced Huangdineijing. Conclusions : 1. Books that upheld Huangdi contained within Hanshu・Yiwenzhi have a common point with the mythical symbol of Huangdi in that they are related to the rule of a nation and the creation of a civilization. Huangdi, who in Huangdineijing bears a need to be understand at this common point of view. 2. The spirit of the period between Warring States and Han can be deduced as "a movement towards unification" and "the development of a civilization infused with spirit of unification." Such spirit of time are reflected in Huangdineijing as Nine Acupuncture(Official Acupuncture) and the establishment of the measuring standards for meridian, bone, and internal organ, and the establishment of the concept of 'Pyungin.' Especially the construction of waterways that connected Huanghe and Yangzijiang river with their tributaries that formed a direct composition of unification was applied to human body in Huangdineijing, thereby establishing the concept of 'Mai'. 3. Unlike Lao Zhuang School of Taoism was not interested in the act of ruling at all, Huangdineijing and its contemporary publication Huangdisijing, present their readers with Number, Law, Rule, Regulation and Governance. Here, the philosophy and the idea which seek "Law" as the methods of ruling the nation by actively participating in the governance of the nation based on the model of natural law and rule appear. Such philosophy and idea is an evidence of the influence of Fajia in accordance with the social and realistic changes witnessed during the time.

유비쿼터스 웹서비스 환경에서 이벤트 기반의 룰 처리 기법 (Event based Rule Processing in Ubiquitous Web Services Environments)

  • 이강찬;이원석;전종홍;이승윤;박종헌
    • 한국정보통신학회논문지
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    • 제10권6호
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    • pp.1101-1105
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    • 2006
  • 웹서비스의 이벤트를 수신하기 위한 Web Services Eventing과 WS-Notification과 같이 현존하는 관련 표준은 하나의 이벤트 묶음을 무조건적으로 수신하거나 하나의 이벤트에 하나의 조건을 제시할 수밖에 없다는 것이 문제점으로 지적되고 있다. 그러나 실제로 이벤트들을 처리하기 위해서는 하나의 이벤트를 수신할 때도 다양한 조건을 제시할 수 있도록 하여, 동일한 이벤트를 받았을 때에도 다양한 조건식에 따라 원하는 작업을 수행할 수 있도록 하는 유연성을 제공하여야 한다. 본 논문은 그러한 유연성을 제공하는 유비쿼터스 웹서비스 환경에서 이벤트 기반의 룰 처리 기법에 대해서 살펴보도록 한다.

복막투석복막염 환자에서 발생한 창자벽공기증 1예 (A Case of Pneumatosis Intestinalis in Peritoneal Dialysis Peritonitis)

  • 정선영;나지훈;최윤정;고성애;조규향;박종원;도준영;윤경우
    • Journal of Yeungnam Medical Science
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    • 제26권1호
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    • pp.49-55
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    • 2009
  • Peritonitis is a serious problem in patients undergoing peritoneal dialysis. Rarely pneumatosis intestinalis can occur as a complication of this infectious process. Pneumatosis intestinalis is a potential life threatening condition with a challenging management. The mortality of peritoneal dialysis patients with pneumalosis intestinalis secondary to mesenteric ischemia is almost 100%. We describe a rare case of pneumatosis intestinalis in a peritoneal dialysis patient who developed Staphylococcus aureus peritonitis which was initially treated with appropriate antibiotics. Since initial response to therapy was not achieved, an abdominal computerized tomography was done which revealed a pneumatosis intestinalis. A laparotomy was performed and small bowel necrosis was seen. A segmental resection with ileostomy, jejunostomy was done. Though surgical treatment was performed, the patient died in 2 weeks after admission. Pneumocystitis intestinalis in peritoneal dialysis peritonitis is a uncommon complication which requires prompt evaluation to rule out mesenteric ischemia as it carries a high mortality and its management will be surgical.

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내부 P제어를 이용한 PID 제어기 튜닝규칙 (PID Controller Tuning Rules Using an Inner P Controller)

  • 김동일;성수환;이지태
    • 제어로봇시스템학회논문지
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    • 제12권12호
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    • pp.1173-1177
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    • 2006
  • Using an inner P controller, a tuning rule useful for processes with wide ratios of time delay over time constant is proposed. Internal model control method and pole assignment method are utilized. It can be used for processes with wide range of the ratio of time delay to time constant without incovenience to choose different tuning rules.

효율적인 패킷 분류를 위한 계층 우선순위 트라이 (Hierarchical Priority Trie for Efficient Packet Classification)

  • 추하늘;임혜숙
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2007년도 하계종합학술대회 논문집
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    • pp.15-16
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    • 2007
  • In order to provide value-added services, next generation routers should perform packet classification for each incoming packet at wire-speed. In this paper, we proposed hierarchical priority trio (Hptrie) for packet classification. The proposed scheme improves the search performance and the memory requirement by replacing empty internal nodes in ordinary hierarchical trio with priority nodes which are the nodes including the highest priority rule among sub-trie nodes.

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원발성 위암과 후두암, 폐암 병발의 1례 (A Case of Triple Primary Cancers in Stomach, Larynx, and Lung)

  • 최주영;장혜정;이민진;심성신;류연주;문진욱;이진화;천은미;장중현
    • Tuberculosis and Respiratory Diseases
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    • 제61권3호
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    • pp.279-284
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    • 2006
  • 다발성 원발성 악성종양은 최근 발생 빈도가 증가하고 있으며 이는 암의 진단 방법의 개선 및 인구의 고령화, 유해물질에 대한 노출증가에 기인한다. 국내에서도 다발성 원발성 악성종양에 대한 연구가 진행되어왔으며, 김등, 윤등이 보고하였다. 그러나 삼중복암의 발생하는 빈도는 매우 낮은 것으로 보고되어있다. 저자들은 이화여대 동대문 병원 내과에 입원한 다발성 원발성 위암, 후두암, 폐암 환자의 1예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

The effect of nanoparticle in reduction of critical fluid velocity in pipes conveying fluid

  • Ghaitani, M.M.;Majidian, A.;Shokri, V.
    • Advances in concrete construction
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    • 제9권1호
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    • pp.103-113
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    • 2020
  • This paper deal with the critical fluid velocity response of nanocomposite pipe conveying fluid based on numerical method. The pressure of fluid is obtained based on perturbation method. The motion equations are derived based on classical shell theory, energy method and Hamilton's principle. The shell is reinforced by nanoparticles and the distribution of them are functionally graded (FG). The mixture rule is applied for obtaining the equivalent material properties of the structure. Differential quadrature method (DQM) is utilized for solution of the motion equations in order to obtain the critical fluid velocity. The effects of different parameters such asCNT nanoparticles volume percent, boundary conditions, thickness to radius ratios, length to radius ratios and internal fluid are presented on the critical fluid velocity response structure. The results show that with increasing the CNT nanoparticles, the critical fluid velocity is increased. In addition, FGX distribution of nanoparticles is the best choice for reinforcement.

70톤 급 초대형 중장비용 머플러 개발 (Development of a muffler for the super heavymachinery in the 70 ton class)

  • 이시복;이원태;남경훈
    • 한국산학기술학회논문지
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    • 제10권10호
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    • pp.2557-2564
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    • 2009
  • 본 연구는 70톤 급 초대형 중장비에 사용되는 머플러를 실험과 경험 법칙을 통하여 개발하였다. 머플러 내부의 파티션 플레이트, 천공관 그리고 파이프 구조를 변경하며 투과손실 성능을 비교하고, 실험 결과를 통하여 머플러의 성능에 영향을 미치는 내부 음향 요소의 최적 조합과 배치를 결정하였다.