• 제목/요약/키워드: Common subject

검색결과 807건 처리시간 0.024초

분류표의 시대구분에 대한 연구 (A Study on the Chronological Division in Classification)

  • 정해성
    • 한국도서관정보학회지
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    • 제35권4호
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    • pp.469-489
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    • 2004
  • 시대구분(연대범주)은 주제와 결합하여 주제의 범위를 특정 연대(시대)로 한정하는 방법으로서 분류표에 따라서 사용기법을 달리 하고 있다. CC와 UDC는 공통구분표를 통해 일관성있고 분명한 시대구분이 가능하다. DDC와 KDC는 표준구분, 역사류, 문학류에 따라 시대구분 기호를 다르게 사용하고 있다.

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Confounding of Time Trend with Dropout Process in Longitudinal Data Analysis

  • Kim, Ji-Hyun;Choi, Hye-Hyun
    • Communications for Statistical Applications and Methods
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    • 제9권3호
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    • pp.703-713
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    • 2002
  • In longitudinal studies, outcomes are repeatedly measured over time for each subject. It is common to have missing values or dropouts for longitudinal data. In this study time trend in longitudinal data with dropouts is of concern. The confounding of time trend with dropout process is investigated through simulation studies. Some simulation results are reported for binary responses as well as continuous responses with patterns of dropouts varying. It has been found that time trend is not confounded with random dropout process for binary responses when it is estimated using GEE.

사용자 독립적 특징 추출을 위한 연구 (A Study on Subject Independent Feature Extraction)

  • Bang, Won-Chul;Han, Jeong-Su;Z. Zenn Bien
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2002년도 춘계학술대회 및 임시총회
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    • pp.123-125
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    • 2002
  • 여러 사람에게서 생체신호를 측정하여 특징을 추출하는 경우 피실험자마다 다른 신체적 또는 생리학적 특징에 의해 같은 클래스로 분류하고 싶어도 다른 클래스로 잘못 분류되는 경우가 발생한다. 이와 같이 N 명의 사람에게서 얻은 생체신호로 M 개의 클래스를 분류하도록 훈련하여 새로운 사람의 생체신호를 M 개의 클래스로 분류하고자 할 때 발생하는 문제를 해결하기 위한 방법으로 피실험자 독립적인 클러스터링 방법을 제안하고자 한다. 이를 위한 수학적 기반으로 동치관계들의 교집합과 합집합에 근거한 새로운 연산자를 정의하고 이를 이용하여 최대 공통 클러스터(Largest Common Cluster, LCC)라는 새로운 개념을 정의한다 이는 여러 사람에게서 얻은 정보에서 최대한 공통의 성질을 갖는 것들을 찾아내는 수학적이고 체계적인 방법이라 할 수 있다. 따라서 일단 LCC를 찾아내면 이를 특징(feature)으로 삼아 패턴분류기를 설계하면 여러 사람에게 적용가능한 생체신호 인식기를 설계할 수 있게 된다.

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Simplified Machine Diagnosis Techniques Using ARMA Model of Absolute Deterioration Factor with Weight

  • Takeyasu, Kazuhiro;Ishii, Yasuo
    • Industrial Engineering and Management Systems
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    • 제8권4호
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    • pp.247-256
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    • 2009
  • In mass production industries such as steel making that have large equipment, sudden stops of production process due to machine failure can cause severe problems. To prevent such situations, machine diagnosis techniques play important roles. Many methods have been developed focusing on this subject. In this paper, we propose a method for the early detection of the failure on rotating machine, which is the most common theme in the machine failure detection field. A simplified method of calculating autocorrelation function is introduced and is utilized for ARMA model identification. Furthermore, an absolute deterioration factor such as Bicoherence is introduced. Machine diagnosis can be executed by this simplified calculation method of system parameter distance with weight. Proposed method proved to be a practical index for machine diagnosis by numerical examples.

지하구조물내 전기재해 방지를 위한 설치지침 및 예방시스템 구축 (Recommended Practice on the Precautinary System and Installation to prevent electrical fire from reoccurring in underground tunnel)

  • 김세동;김영진;강재모
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 춘계학술대회논문집
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    • pp.337-341
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    • 2005
  • Most utiltity systems are subject to frequent changes, often due to increased loads and demand to up-grade quality of service provided. Urban renewal, expressway construction and suburban growth have also caused significant changes in urban utility distribution systems. Recently, it is required that a guideline for planning of a complete system, the reasonable design and construction methods for the efficient installation common utility tunnels must be estabilished. It prompts drastic measures to guard cities and their inhabitants against the horror of massive fires in the future. Preparedness holds the key to safety.

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EXPLORATORY PHOTOCHEMICAL STUDY ON THE o-NITROBENZYLSULFONYL DERIVATIVES

  • Chang, Sun-Ki
    • Journal of Photoscience
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    • 제1권1호
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    • pp.67-68
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    • 1994
  • INTRODUCTION : The photochemistry of nitro chromophore has been the subject of intense study only in recent years. Unlike the carbonyl functional group, of which the photochemistry has been quite extensively studied and fairly well understood, as a result of excellent work done by numerous physical and organic photochemists alike, the nature of photochemistry of nitro group has only recently been systematically explored. The photochemistry of nitro group exhibits general features of the photochemistry of the carbonyl groups such as hydrogen abstraction by the diradical species generated from the n-$\pi$$^*$ excited state of the nitro group. Other photochemical pathways common to the carbonyl group such as the biradical intermidiate formation, photocycloelimination, and cydoaddition reactions are also open for the nitro group. Of all the photochemical reactions of the nitro group mentioned above, hydrogen abstraction by the n-$\pi$$^*$ excited state of the nitro group has drawn much attention by synthetic organic chemists and polymer chemists. In the field of organic synthesis, above mintioned photochemical reaction has been utilized in the photoprotection-deprotection chemistry.

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임상 경두개 도플러 검사 (Clinical Transcranial Doppler)

  • 김종순;류재관
    • 대한물리치료과학회지
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    • 제6권4호
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    • pp.153-165
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    • 1999
  • The transcranial Doppler(TCD) is a technique for measuring blood flow velocity of intracranial and extarcranial arteries. This examination based on Doppler effect which was first formulated in 1842 by the Austrian physicist Christian Doppler. In 1982, Rune Aaslid first maked 2MHz pulsed probe and recording intracranial vessels with transcranially. There are six criteria utilized in gaining positive identification of the intracranial vessels. The six criteria are as follows l)acoustical windows 2)depth of sample volume 3)direction of flow 4)spatial relationship of ACA and MCA bifurcation 5)mean velocity and 6)response common carotid artery compression and/or oscillation test. The affected factors for TCD examination are angle of insonation, posture of subject, age, gender, hematocrit, metabolic factors, and cardiac output. Clinical application of TCD are detection of stenosis, occlusion, emboli, thrombsis in intracranial and extracranial arteries and evaluation of cerebral arterovenous malformation, collateral capacity in the circle of Willis, ischemia cerebrovascular disease, stroke patient and vertebrobasilar system.

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집약초지의 조성기술 (Agronomic Practces on Intensive Pasture Establishment)

  • 김동암;조무환
    • 한국초지조사료학회지
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    • 제2권2호
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    • pp.1-15
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    • 1981
  • In reviewing of the literature concerning agronomic practices on intensive pasture establishment the following suggestions were made : (1) The seedbed preparation should be involved physical manipulation of the soil tilth and consolidation of the soil by harrows and heavy roller. (2) In terms of methods of sowing, drilling favours the first and broadcasting the second however, the apparent superiority of band sowing over the above conventional methods is to reduce the direct toxic chemical effects from fertilizers to germinating seeds. (3) The most satisfactory seeding depth for grasses and legumes is commonly agreed to be approximately 1.3cm and seeding depth greater than 2.5cm seems to be generally detrimental. (4) Autumn and spring are most common sowing periods for grasses and legumes, however, early autumn being the most generally favoured, particularly in areas not subject to severe winter kill. (5) Select nurse crop species or cultivars which make Bess demands on light, nutrients and water, and lower seed rates should be used. (6) Seeding mixtures should be simple rather than complex and aggressive species should be included to a minor extent.

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과민성장증후군 환자의 정전가미이진탕(正傳加味二陳湯) 투여(投與) 1례(例) (One Case of Irritable Bowel Syndrome Patient Treated With Jengjengamiyijin-tang (Zhengchuanjiaweierchen-tang))

  • 김회영;남효익;손현수;박상무
    • 대한한의학방제학회지
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    • 제15권2호
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    • pp.179-186
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    • 2007
  • The irritable bowel syndrome(IBS) is the most common gastrointestinal disorder in clinical practice and is characterized by abdominal pain associated with a chronic disturbance of defecation. The subject is a-69-year-old man who has abdominal pain, chronic diarrhea. anorexia. general weakness and has been diagnosed as irritable bowel syndrome. We diagnosed this patient as the Gastrointestinal Phlegm(食痰) and prescribed Jengjengamiyijin-tang (Zhengchuanjiaweierchen-tang). In the result, we had improvement of his symptoms.

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최대 지연시간을 고려한 ET 모델에서의 단일 기계 일정계획 (Single Machine Dcheduling with Maximum Allowable Tardiness in ET Model)

  • 조성아;조충호;이동훈;김채복
    • 한국경영과학회지
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    • 제23권1호
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    • pp.29-41
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    • 1998
  • This paper addresses the problem of scheduling a set of jobs with a common due data on a single machine. The objective is to minimize the sum of the earliness and tardiness of jobs subject to $T_{max}{\le}{\Delta}\;for{\Delta}{\ge}0$. Properties for the $MAD/T_{max}$ problem are found and the problem is shown to be NP-complete in the ordinary sense. According to the range of Δ, the problem can be solved in polynomial time. Also, some special cases where an optimal schedule is found in polynomial time are discussed.

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