• 제목/요약/키워드: Periodic Change

검색결과 392건 처리시간 0.025초

국내 종합병원의 형태 유형 변화에 관한 연구 (A Study on the Change of Form Type in General Hospital)

  • 김은석;양내원
    • 한국실내디자인학회논문집
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    • 제23권6호
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    • pp.195-203
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    • 2014
  • This study selects factors affecting form type of hospital architecture by considering studies and references on hospital architecture type in korea and other countries in general. Also this study classifies general hospitals chronologically and analyzes type change of general hospitals in relation with periodic change of healthcare environment. Through this, this study aims to analyze chronological change of general hospitals' form type and provide the current of hospital architecture's general type. The form type classification of this study is classification according to the form of ward, classification according to the relationship between ward and D.T.D(Diagnostic and Treatment department), classification according to the relationship between O.P.D(Out Patient department) and D.T.D, classification according to the rate of centralization, classification according to the circulation system. The form type of ward changed from plate type to tower type, and the circulation system of ward changed from middle corridor to double corridor, the number of Team Nursing chaged from 1 to 2 in 1990. On the other hand the chage of others classifications took place from 1990' to 2010'. It is judged that this overall change is appeared by a change from an inpatien-oriented system to an outpatient-oriented system followed by an increase in number of outpatients, an increase in amenities in ground floor and adoption of healing environment for patients and visitors.

MODIS NDVI 시계열 자료의 하모닉 분석을 통한 지표 식생 변화 탐지 (Land-Cover Vegetation Change Detection based on Harmonic Analysis of MODIS NDVI Time Series Data)

  • 정명희;장은미
    • 대한원격탐사학회지
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    • 제29권4호
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    • pp.351-360
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    • 2013
  • MODIS NDVI 시계열 자료에 하모닉 분석을 적용하면 계절에 따른 식생의 연간 변화 패턴을 이해할 수 있다. 하모닉 분석은 시간에 따라 형성된 시계열 자료의 복잡한 파형의 형태를 일련의 정현파 파형(sinusoidal waves)의 합으로 분해하고 진폭과 위상으로 정의되는 각 파형의 특성을 통해 시계열 자료의 패턴을 분석하는 방법이다. 본 논문은 NDVI 시계열 자료에 하모닉 모형을 적용하여 각 구성 성분의 진폭과 위상을 측정하고 이러한 파라미터들의 변화를 분류하여 식생의 연간 변화를 탐지하는 방법론을 제안하고 있다. 이를 통해 장기간에 걸친 식생 변화 지역을 모니터링할 수 있고 또한, 이 과정에서 하모닉 모형을 통해 미관측 자료나 노이즈 자료를 복원하여 시계열자료를 재구축할 수 있는 장점도 있다. 본 연구에서는 시뮬레이션 자료를 통해 하모닉 분석의 유용성에 대해 테스트하였고, 2006년부터 2012년까지 총 7년간 북한 개마고원 부근의 MODIS NDVI 식생 자료에 하모닉 모형을 적용하여 연간 변화 지역을 탐지하고 연간 식생변화지역맵을 작성하였다. 이렇게 작성된 연간 식생변화지역맵은 장기적인 식생변화 모니터링을 위한 기초 맵으로 활용될 수 있을 것으로 기대된다.

교육시설 정책 변천에 따른 초등학교 건축공간 변화 추이 분석 (An Analysis of Transition about Architectural Space on the Elementary Schools with the Change of Policy for School Facilities)

  • 정주성
    • 교육시설 논문지
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    • 제19권2호
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    • pp.3-12
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    • 2012
  • This study is carried out to analyze transition about educational facilities of elementary schools with the change of policy and to find out a developmental direction for qualitative improvement. An analysis of blueprints is done to 34 elementary schools representing periodic characteristics after the 1960's. As a result, various cases were shown in arrangement type, unit space, block planning and plane planning of the schools after a abolition of law about the standardization of educational facilities on 1997, however, they were showing a tendency to simplify after the introduction of BTL on 2005. Spatial composition factors were very various in the schools planned from the middle of 1990's to the early of 2000's. Meanwhile, nearly fifty percent of occupying ratio about learning space in the schools of standard type was gradually decreased by modernization planning on 1990's. However, it was increased a little again after the BTL. In case of living area, the occupying ratio was comparatively high in the schools having characteristics of 1990's and it also tends to increase after the introduction of BTL.

방송 채널 효율 향상을 위한 그룹 계층 구성 기반 접근 제어 시스템 (Conditional Access System with A Group Hierarchy to Improve Broadcasting Channel Efficiency)

  • 양장훈;김동구
    • 한국항행학회논문지
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    • 제13권5호
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    • pp.726-735
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    • 2009
  • 본 논문에서는 방송 시스템에서 채널의 대역폭이 제한되는 상황에서 유효 가입자 제어를 위한 메시지 전송 오버헤드를 감소시키는 접근 제어 시스템을 제안하였다. 이를 위해서 IP 기반 멀티캐스트에 제안되었던 트리 계층 구조의 키 개정 시스템을 도입하여 가입자를 트리 구조에 직접 매핑하는 경우와 가입자를 채널 그룹별로 나누어 채널 그룹을 트리 구조에 적용하는 시스템을 고려하였다. 제안 시스템의 효율성을 평가하기 위해 기존의 시스템과 제안 시스템에 대해서 보안을 위한 주기적인 키 개정을 위한 오버헤드 전송율과 동적이면서 비주기적으로 가입자의 변동이 발생을 할 때의 오버헤드 전송율을 분석하였다. 다양한 시스템 환경에서 제안 시스템은 기존 시스템에 비해서 가입자의 변동이 발생할 경우에 수 배에서 수십 만배의 키 개정을 위한 메시지 오버헤드 전송율을 크게 감소시키는 것을 분석 평가를 통해서 확인하였다.

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우주 유연 붐의 열적 유기 진동에 관한 연구 (A Study on Thermally-induced Vibration of Space Flexible Booms)

  • 공창덕;오경원;방조혁
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.1631-1636
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    • 2003
  • The purpose of this study is to analyze the phenomena of the thermally-induced vibration for the flexible space structure due to abrupt change of radiation heating circumstance using the numerical analyze and experiment test. In order to verify this structure, numerical approaches on the simplified flexible tube were compared with experimental test results at the ground experimental facility In this analyze, it was found that the thermal deformation occurs firstly due to fast radiation heating of flexible structure and then the thermally-induced vibration would be induced due to small periodic change of temperature. According to comparison of numerical and experimental result, in case of no tip mass, the first mode vibration by the numerical analyze was O.78Hz same as that of the experimental result However in case of increase tip-masses of 8g l6g, 50g and 100g, the first modes vibration theoretical analyze were 1.75Hz, 1.3Hz, 0.87Hz and O.73Hz, in decrease trend respectively and those by experimental test were 234Hz, 1.5Hz, O.78Hz and O.78Hz in decrease trend respectively Although using the simpled equation for the estimation, the estimation results were similar to experimental results.

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過大, 過小應力下에서의 疲勞크랙發생 傳播擧動 (II) - 탄소동재의 내부크랙을 중심으로- (Behavior of Initiation and Propagation of Fatigue Crack under Periodic Overstressing(II) - About the Inside Crack of the Caron Steel-)

  • 송삼홍;원시태
    • 대한기계학회논문집
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    • 제10권2호
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    • pp.188-197
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    • 1986
  • 본 연구에서는 응력이 변동되는 경우 내부크랙 전파특성을 중심으로 내부크랙 전파거동을 표면크랙 전파거동과 비교 검토하였다.

주유동 맥동과 경계층 와류의 상호작용이 벽면 열전달에 미치는 영향 (Heat Transfer Characteristics of the Interaction Between Bulk Flow Pulsation and a Vortex Embedded in a Turbulent Boundary Layer)

  • 강새별;맹두진;이준식
    • 대한기계학회논문집B
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    • 제25권3호
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    • pp.381-388
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    • 2001
  • Presented are heat data which describe the effect of interaction between bulk flow pulsations and a vortex embedded in a turbulent boundary layer. The pulsation frequencies are 3 Hz, 15 Hz and 30 Hz. A half delta wing with the same height as the boundary layer thickness is used to generate the vortex flow. The convection heat transfer coefficients on a constant heat-flux surface are measured by embedded 77 T-type thermocouples. Spanwise profiles of convection heat transfer coefficients show that upwash region of vortex flow is influenced by bulk flow pulsations. The local heat transfer coefficient increases approximately by 7 percent. The increase in the local change of convection heat transfer coefficient is attributed to the spanwise oscillatory motion of vortex flow especially at the low Strouhal number and to the periodic change of vortex size.

방사선조사가 하악과두에 미치는 영향에 관한 전자현미경적 연구 (ELECTRON MICROSCOPIC STUDY OF THE IRRADIATION EFFECT ON THE RAT MANDIBULAR CONDYLE)

  • 박명선;박태원
    • 치과방사선
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    • 제26권2호
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    • pp.45-63
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    • 1996
  • In attempt to determine radiation effect on the mandibular condyle of the growing rat, 27 white female rats (Sprague-Dawley) were divided into 3 groups and irradiated respectively 5Gy, 10Gy, 20Gy using MK Cell Irradiator. Mandibular condyles from rats on the day of 1, 7, 14 after the irradiation day were obtained, sectioned sagittally and examined by light microscopy, and thereafter middle portion through anteroposterior direction on the sagittal plane was selected to examine the ultrastructural change by transmission electron microscopy. The obtained results are followings. 1. In the proliferative zone some cells showed little organelles in case of 5Gy irradiation, in addition the number of degenerative cells increased and in case of 10Gy irradiation, and in case of 20 Gy irradiation total number of cells decreased. 2. In the hypertrophic zone, narrowing of width and partial disorder in hypertrophic process were noted in case of 5 Gy irradiation, and more prominent narrowing of width and more irregular disorder in hypertrophic process in case of both 10Gy and 20Gy irradiation. 3. In the upper hypertrophic zone some chondrocytes seemed to be dying and the polarity of nuclei could not be seen, if any. 4. The periodic observation showed the severest change at day 7 and the signs of recovery at day 14 after irradiation.

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차륜의 찰상결함 진단을 위한 켑스트럼 분석 방법 연구 (A Study on Cepstrum Analysis for Wheel Flat Detection in Railway Vehicles)

  • 김거영;김현태;구정서
    • 한국안전학회지
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    • 제31권3호
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    • pp.28-33
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    • 2016
  • Since defects in the wheels of railway vehicles, which occur due to wears with the rail, cause serious damage to the running device, the diagnostic monitoring system for condition-based maintenance is required to secure the driving safety. In this paper, we studied to apply a useful Cepstrum analysis to detect periodic structure in spectrum among the vibration signal processing techniques for the fault diagnosis of a rotating body such as wheel. In order to analyze in variations of train velocity, the Cepstrum analysis was performed after a domain change of the vibration signal from time domain to rotation angle domain. When domains change, it is important to use a interpolation for a uniform interval of the rotation angle. Finally, the Cepstrum analysis for wheel flat detection was verified by using the vibration signal including the disturbance resulting from the rail irregularities and the vibration of bogie components.

Change in radiation characteristics outside the SNF storage container as an indicator of fuel rod cladding destruction

  • Rudychev, V.G.;Azarenkov, N.A.;Girka, I.O.;Rudychev, Y.V.
    • Nuclear Engineering and Technology
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    • 제53권11호
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    • pp.3704-3710
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    • 2021
  • The characteristics of the external radiation on the surface of the casks for spent nuclear fuel (SNF) storage by dry method are investigated for the case when the spatial distribution of SNF in the basket changes due to the destruction of the fuel rod claddings. The surface areas are determined, where the changes in fluxes of neutrons, produced by 244Cm actinide, and γ-quanta, produced by long-lived isotopes, are maximum in the result of the decrease in the height of the SNF area. Concrete (VSC-24) and metal (SC-21) casks are considered as examples. The procedure of periodic measurement of the dose rate of neutrons or γ-quanta at the specified points of the cask surface is proposed for identifying the fuel rod cladding destruction. Under normal operation, the decrease in the dose rate produced by neutrons as the function of SNF storage duration is determined by the half-life of 244Cm, and for γ-quanta - by the half-lives of long-lived SNF isotopes. Consequently, a stepwise change in the dose rate of neutrons or γ-quanta, detected by the measurements, as compared to the previous one, would indicate the destruction of the fuel rod claddings.