• Title/Summary/Keyword: Periodic change

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

  • Kim, Eun-Seok;Yang, Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.23 no.6
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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.

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

  • Jung, Myunghee;Chang, Eunmi
    • Korean Journal of Remote Sensing
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    • v.29 no.4
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    • pp.351-360
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    • 2013
  • Harmonic analysis enables to characterize patterns of variation in MODIS NDVI time series data and track changes in ground vegetation cover. In harmonic analysis, a periodic phenomenon of time series data is decomposed into the sum of a series of sinusoidal waves and an additive term. Each wave is defined by an amplitude and a phase angle and accounts for the portion of variance of complex curve. In this study, harmonic analysis was explored to tract ground vegetation variation through time for land-cover vegetation change detection. The process also enables to reconstruct observed time series data including various noise components. Harmonic model was tested with simulation data to validate its performance. Then, the suggested change detection method was applied to MODIS NDVI time series data over the study period (2006-2012) for a selected test area located in the northern plateau of Korean peninsula. The results show that the proposed approach is potentially an effective way to understand the pattern of NDVI variation and detect the change for long-term monitoring of land cover.

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

  • Jeong, Joo-Seong
    • Journal of the Korean Institute of Educational Facilities
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    • v.19 no.2
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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.

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

  • Yang, Jang-Hoon;Kim, Dong-Ku
    • Journal of Advanced Navigation Technology
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    • v.13 no.5
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    • pp.726-735
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    • 2009
  • In this paper, we proposed a novel conditional access system to reduce the overhead transmission rate for messages which verify the entitlement of subscribers in bandwidth-limited system. We adapted a key update system with the tree structure which had been used for IP multicast to a group hierarchy for the subscriber groups or channel groups. We also analyzed the overhead transmission rate for periodic key update and aperiodic one for change in a subscriber. The numerical evaluations show that the proposed system can significantly reduce the overhead transmission rate for dynamic subscriber change up to several hundred thousands times for various system configuration.

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

  • Kong, Chang-Duk;Oh, Kyung-Won;Bang, Jo-Hyug;Sugiyama, Y.
    • Proceedings of the KSME Conference
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    • 2003.11a
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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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Behavior of Initiation and Propagation of Fatigue Crack under Periodic Overstressing(II) - About the Inside Crack of the Caron Steel- (過大, 過小應力下에서의 疲勞크랙發생 傳播擧動 (II) - 탄소동재의 내부크랙을 중심으로-)

  • 송삼홍;원시태
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.10 no.2
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    • pp.188-197
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    • 1986
  • With respect to structural carbon steel(SM 22C), it was studied how the overstress or the understress has effects on fatigue inside crack propagation curve of a two level stress. Obtained results are summarized as follows. (1) The overstress or the understress, at a slip band occurrence stage, does not change the inside crack propagation curve because the crack closure and opening phenomena do not happen. (2) The overstress, at a crack propagation stage, does not change the inside crack propagation curve because the crack closure of overstress in compressive state is nearly same that of base stress in compressive state. (3) The understress, at a crack propagation stage, give rise to an acceleration of crack growth because the crack closure of understree in compressive state is more open than that of base stress in compressive state and the phenomenon is the essential increase of the actual applied stress of the specimen.

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

  • Gang, Sae-Byeol;Maeng, Du-Jin;Lee, Jun-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.3
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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.

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

  • Park Myoung Seon;Park Tae Won
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.26 no.2
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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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A Study on Cepstrum Analysis for Wheel Flat Detection in Railway Vehicles (차륜의 찰상결함 진단을 위한 켑스트럼 분석 방법 연구)

  • Kim, Geoyoung;Kim, Hyuntae;Koo, Jeongseo
    • Journal of the Korean Society of Safety
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    • v.31 no.3
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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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    • v.53 no.11
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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.