• 제목/요약/키워드: CHIEF Method

검색결과 238건 처리시간 0.024초

시간 영역 음향 경계요소법에서의 비유일성 문제 해결을 위한 방법에 관하여 (On the Solution Method for the Non-uniqueness Problem in Using the Time-domain Acoustic Boundary Element Method)

  • 장해원;이정권
    • 한국음향학회지
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    • 제31권1호
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    • pp.19-28
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    • 2012
  • Kirchhoff 적분식을 이용하여 외부 음향 문제의 시간 영역 응답을 계산하는 경우, 주파수영역 해석과 마찬가지로 가상적인 내부 음향 모드에 기인한 비유일성 문제가 발생한다. 이를 해결하는 방법들 중의 하나로서 CHIEF(Combined Helmholtz Integral Equation Formulation) 방법이 쓰이는데, 이는 몇몇 내부 수음점의 응답을 0으로 추가하여 구속하는 조건을 부가하는 기법이다. 이 기법은 주파수 영역 경계요소법에서는 간편한 수식 때문에 많이 사용되고 있지만, 시간 영역에서는 사용된 예가 없다. 본 연구에서는 대상체 내부의 가상 수음점과 경계 표면의 절점들간의 최소 거리에 대한 지연시간을 고려하여, 계산하고자 하는 미지수인 현재 시간의 경계 표면 음장을 구속함으로써, 시간 영역 해석에 적합하도록 CHIEF 방법을 수식화하였다. 예제로서, 반지름 방향으로 진동하는 구의 음향 방사 문제를 다루었다. CHIEF 방법을 적용함에 따라 저차의 내부 음향 모드에 기인한 비유일성 문제를 해결할 수 있었고, 비요동 모드에 의한 수치적 불안정성을 피할 수 있었다. 그러나, 유효주파수 밖에 남은 내부 음향의 고차모드들에 의한 수치적 불안정성은 증가하였다.

음향방사문제에서 직접경계요소법의 비유일성 회피방법에 관한 고찰 (Investigation on Method Avoiding Non-uniqueness of Direct Boundary Element Method in Acoustic Wave Radiation Problem)

  • 김국현
    • 한국산학기술학회논문지
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    • 제11권7호
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    • pp.2328-2333
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    • 2010
  • 직접경계요소법은 음향방사문제 해석에 널리 적용되는 수치해석기법중 하나이지만, 외부 음향방사 문제에 있어서는 방사면 내부공간의 고유주파수 근방에서 비유일성이 나타나게 된다. 이를 해결하기 위한 방법으로 CHIEF 방법이 일반적으로 적용되어 왔으며, 최근 들어서는 ICA-Ring 방법과 같은 새로운 기법이 제안되어 해의 정확도 향상에 기여하고 있다. 본 논문에서는 앞서 언급한 두 가지 비유일성 회피기법들의 특성을 살피고, 각각의 기법 구현을 포함한 직접경계요소법 기반의 수치해석 코드를 작성한다. 또한, 법선방향 균일속도로 진동하는 구의 음향방사문제에 대한 수치해석을 수행하고 그 결과를 해석 해와 비교하여 각각의 기법들에 대한 비유일성 회피 성능을 고찰한다.

모 한방병원 소아과 외래 환자의 주소증에 대한 연구 ('01-'04년) (A Study of the Chief Complaint of Pediatric Outpatients in the Oriental Hospital)

  • 장규태;김장현;최은영
    • 대한한방소아과학회지
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    • 제19권2호
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    • pp.197-213
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    • 2005
  • Objective : The purpose of this study was to investigate chief complaints of pediatric outpatients .Fin the oriental hospital and search for a trend of patients and their symtoms. Method : The study was composed of 2,915 new patients aged between 0 and 20 who had been visited pediatrics in ${\bigcirc}{\bigcirc}$ university oriental hospital from 2001 to 2004. Results : The percentage of new patients decreased every year with 30.7% in 2001, 25.5% in 2002, 24.1% in 2003, 17.8% in 2004. The age distribution showed 9.9% in infancy patients, 62.6% in early childhood, 16.8% in late childhood, 10.6% in adolescence. The percentage of infants decreased every year with 13.3% in 2001, 9.4% in 2002, 8.8% in 2003, 7.1% in 2004. The percentage of adolescents increased every year with 8.0% in 2001, 9.6% in 2002, 12.8% in 2003, 13.5% in 2004. Systemic division of chief complaints was respiratory symtoms(37.6%), general symtoms(26.1%), digestive symtoms(19.2%), skin symtoms(6.8%), nervous and mental symtoms (6.1%), urinary symtoms(2.2%), musculoskeletal symtoms(1.3%) and others(0.7%) in order of frequency. The main chief complaints were nasal mucus/obstruction(17.5%), weakness(16.9%), cough(12.8%), loss of appetite(9.8%), inappropriate growth(4.3%), atopic skin problem(3.4%), repeated common cold(2.4%), abdominal pain(2.4%), vomiting (2.2%), diarrhea(2.0%) and fever (1.9%). Loss of appetite, inappropriate growth and repeated common cold increased every year. Diarrhea and convulsion decreased every year. Conclusions : The two main causes of visit of patients were respiratory problems and improvement of general condition. More data of patients should be accumulated for further study. Not only analysis according to chief complaint, but also analysis according to diagnosis will accomplish more aaccurate information about disease of childrens in the future.

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임상적 통계를 통한 홍채진단의 신빙성 연구 (Clinical Study of Iris Diagnosis by means of Statistical Analysis)

  • 김경수;박병민;차용석;김용정;윤종민;이승언;차숙;김강산
    • 동의생리병리학회지
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    • 제17권6호
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    • pp.1538-1542
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    • 2003
  • This Study was carried out for proof of confidence of Iris Diagnosis. We analyzed relation between Iris Signs and Chief Complain, and then analyzed relation between Iris Signs and Past History. The rate of relation between Iris Signs and Chief Complain was 72.1 %. The rate of relation between Iris Signs and Past History was 52.9%. synthetically, We had known that this diagnosis method have probability of 79.7%. It was confirmed that there are close correlations between Iris Signs and Chief Complain and between Iris Signs and Past History.

${\cdot}$북한의 국가원수 경호조직에 관한 연구 (A Study on The Protection Organization for The Chief of State in North and South Korea)

  • 김두현
    • 시큐리티연구
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    • 제1호
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    • pp.17-50
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    • 1997
  • I study on the security organization for the chief of state in North and South Korea. The paper, purporting to analyze security system in comparative prospectives, comprise four chapters. Chapter I Which sets out purpose, scope and method, is followed by Chapter II , dealing largely with the power structure on The Socialist Constitution of Democratic People's Republic of Korea, the protection organization and security activities for the chief of state in North Korea. Chapter III concerns the security environment - terrorist groups, firearms, explosives, suspects, movements of hostile countries and orthers - and the protection organization on The Presidential Security Service for the president in South Korea, culminating in projection of certain problem area. It is followed by concluding observation made in Chapter IV. To be operated security systems effectively, these need to be regulated according to a protective scale, function, authority of a existing.

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데이터 웨어하우징을 이용한 공군 EIS 아키텍처 (An Executive Information Systems Architecture for the Air Force Using Data Warehousing)

  • 최준섭;서의호;서창교
    • Asia pacific journal of information systems
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    • 제8권3호
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    • pp.1-20
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    • 1998
  • We propose an Executive Information Systems (EIS) Architecture for chief officers of the Air Force using data warehousing method. This architecture has two main proposes. The one is to provide the information for chief officers to control and command their organizations effectively by analyzing operation data at normal times. The other is to provide chief officers with the information about current situation so that they may make right and rapid decisions at emergency. The architecture introduced here is one that analyzes operational trends as well as current trends in a hierarchical organization environment. System analysis and design techniques for the Air Force EIS such as data flow diagram, system structure, entity-relational diagram, and third normal form of relational database were presented. After prototype screens are demonstrated, benefits of new EIS architecture were also discussed as a conclusion.

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소아(小兒) 외래환자(外來患者)의 주소증(主所症)에 관한 임상적(臨床的) 고찰(考察) (An Observation of the Chief Complaints of Pediatric Outpatients)

  • 이승연
    • 대한한방소아과학회지
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    • 제15권1호
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    • pp.203-216
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    • 2001
  • Objective : The purpose of this study is to investigite the more effective oriental medical treatment in pediatric diseases and its clinical applicability and chief complaints at oriental pediatrics in an area of busan and kyeungnam. Method : 884 new patients of theirs ages between 0 term 20 years who were treated at the pediatrics in Dong-Eui Oriental Medicine Busan Hospital from 1. 2000 to 29. Feb. 2001 Result : 1. The number of male cases was 514 (58%) and female cases 370 (42%) an so male cases 1.38 more than female. In age distribution, 0-1year: 242 patients(27.4%), 2-6years: 455 patients(51.4%), 7-20years: 187 patients(21.2%). 2. The Chief Complaint according to systemical division was Resparatory diseases (37.4%) for common cold, chronic cought, take a easy cold etc and the Digestive diseases(23.6%) for anorexia, diarrhea, abdominal pain etc and Nervous also Mental(11.8%) diseases for sezure, tic, etc and Allergic diseases(6.2%) for atopic dermititis, allergic rhinitis, etc and Physique diseases(5.4%) for short stature, leg pain, etc and Genaral symptoms(4.5%) for sweat profusely, headache, etc and Urinary diseases(3.3%) for bed wetting, frequently voiding, etc Discussion : 1. The Chief Complaint cannot be found a regional specificity 2. The oriental medicine treatment was still congnated as a way to improve the weakness by patients, also was widely noised about preventive medicine. In particular, Respiratory and Disestive diseases are dependent on the oriental medicine. 3. The new diseases and the new treatment method should be investigated as field of oriental medical treatment.

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무속적 해석을 통한 제주도 전통주거공간의 이해에 관한 연구 (A Study on the Traditional house in Cheju by Shamanist Interpretation)

  • 최재권
    • 한국실내디자인학회논문집
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    • 제13호
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    • pp.124-129
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    • 1997
  • The purpose of this study is understanding the principle of space construction in traditional houses in Cheju under the premise of house being the dweller's place. I studied it by shamanist interpretatiov. First I understood the quality and meaning of space by the theory of space and shamanism. As the method of study. I studied the space theory and shamanism and had a general idea of them. And then I looked upon the concept of space as residence and analyzed the traditional houses in Cheju. The conclusion of the study is this. I considered shamanism as a part of their way of life. Thus shamanism was a chief idea of Cheju people's thought, religion, and a view of the world. Naturally shamanism was the chief principle with which Cheju people constructed the residence. Because this cultural social aspect of shamanism, it is understood and used as the principle of space construct in modern architecture of Cheju.

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응급의료센터를 내원한 환자의 주증상과 주진단 분포에 관한 연구 (Research about chief complaint and principal diagnosis of patients who visited the university hospital emergency room)

  • 이경숙
    • 디지털융복합연구
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    • 제10권10호
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    • pp.347-352
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    • 2012
  • 본 연구에서는 2011년1월1일부터 2011년 6월 30일까지 6개월 동안 대학병원 응급실로 방문하여 내과로 입원한 환자 889명을 조사대상으로 응급의료센터에 방문한 환자의 주호소와 주진단에 대한 분포를 확인하고, 기존의 질병분류 방법인 ICD와 일차 진료를 세부 분류하는 방법인 ICPC를 비교하고자 하였다. 분석방법으로는 환자들의 인구통계학적인 측면을 살펴보기 위해 빈도분석이 시행되었으며, ICD와 ICPC에 따른 주호소 분포를 알아보기 위한 교차분석을 시행하였다. 다음과 같이 분석을 시행한 결과 주증상중 Abdominal pain이 17.7%, dyspnea가 13.5%, Fever가 12.5% haematemesis가 9.8%로 주로 일차의료에서 사용되는 주호소 증상이 전체의 54.5%를 차지하는 것으로 나타나 응급의료센터에서 일차 진료 분류법을 사용하는데 적합한 것으로 예상되었다. 또한 진단명중 abdominal pain의 경우 ICD에서 R10으로 116(18.7%)명이 분류되었지만 ICPC에서는 epigastric(11.5%)과 general(5.8%)로 나뉘어 분류되어 세분화 되는 것으로 나타났다. 즉, 현재 병원에서 시행되고 있는 ICD 분류법 보다는 일차 진료 분석에 초점이 맞춰진 ICPC 분류법이 좀 더 세분된 환자분류에 용이하다는 것을 알 수 있다. 비록 본 조사에 사용된 자료가 1개 병원에 그치고 있어서 자료의 대표성이 확보되기는 어렵지만, ICPC가 응급의료에 있어 분류가 가능하고 기존의 분류법 보다 세분된 환자분류가 용이하다는 점에서 그 의의가 있다.