• Title/Summary/Keyword: Spatial operation

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Image Retrieval Using the Color Feature and the Wavelet-Based Feature (색상특징과 웨이블렛 기반의 특징을 이용한 영상 검색)

  • 박종현;박순영;조완현
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.487-490
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    • 1999
  • In this paper we propose an efficient content-based image retrieval method using the color and wavelet based features. The color features are extracted from color histograms of the global image and the wavelet based features are extracted from the invariant moments of the high-pass band image through the spatial-frequency analysis of the wavelet transform. The proposed algorithm, called color and wavelet features based query(CWBQ), is composed of two-step query operations for efficient image retrieval: the coarse level filtering operation and the fine level matching operation. In the first filtering operation, the color histogram feature is used to filter out the dissimilar images quickly from a large image database. The second matching operation applies the wavelet based feature to the retained set of images to retrieve all relevant images successfully. The experimental results show that the proposed algorithm yields more improved retrieval accuracy with computationally efficiency than the previous methods.

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Detection of 2002-2003 El Ni${\tilde{n}}$o Using EOS and OSMI Data

  • Lee, S.H.;Lim, H.S.;Kim, J.G.;Jun, J.N.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1413-1414
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    • 2003
  • Interannual variability in the patterns of satellitederived pigment concentrations, sea-level height anomaly, sea surface temperature anomaly, and zonal wind anomaly are observed during the 2002-2003 El Ni${\tilde{n}}$o. The largest spatial extent of the phytoplankton bloom was recovery from El Ni${\tilde{n}}$o over the equatorial Pacific. The evolution towards a warm episode (El Ni${\tilde{n}}$o) started from spring of 2002 and continued during January 2003, while equatorial Sea Surface Temperature Anomaly (SSTA) remained greater than +1$^{\circ}$C in the central equatorial Pacific. The EOS (Earth Observing System) and OSMI (Ocean Scanning Multispectral Imager) data are used for detection of dramatic changes in the patterns of pigment concentration during El Ni${\tilde{n}}$o.

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Extended R-Tree with Grid Filter for Efficient Filtering (효율적인 여과를 위한 그리드 필터를 갖는 R-Tree 의 확장)

  • 김재흥
    • Spatial Information Research
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    • v.8 no.1
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    • pp.155-170
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    • 2000
  • When we use R-Tree,a spatial index, to find objects matches some predicate, it often leads to an incorrect result of perform filtering step only with MBR. And , each candidates need to be inspected to conform if it really satisfies with given query, so called, 'refinement step'. In refinement step. we should perform disk I/O and expansive spatial operations which is the cause of increasing retrieval costs. Therefore, to minimize the number of candidate after filtering step, two-phase filtering methods were studied, but there was many problems such as inefficiency of filtering,maintenance of additional informations and reconstruction of data resulted from the loss of original information. So , in this paper, I propose an Extended R-Tree which provides ability to retrieve spatial objects only with some simple logical operations using Grid Table, truth table strong the information about the existence of spatial objects, in second filtering step. Consequently , this Extended R-Tree using Grid Filter has low cost of operation for filtering because of efficient second filtering step, and better filtering efficiency caused by high quality of approximation.

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Analysing Spatial Usage Characteristics of Shared E-scooter: Focused on Spatial Autocorrelation Modeling (공유 전동킥보드의 공간적 이용특성 분석: 공간자기상관모형을 중심으로)

  • Kim, Sujae;Koack, Minjung;Choo, Sangho;Kim, Sanghun
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.20 no.1
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    • pp.54-69
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    • 2021
  • Policy improvement such as the revision of the Road Traffic Act are proposed for personal mobility(especially e-scooter) usage. However, there is not enough discussion to solve the problem of using shared e-scooter. In this study, we analyze the influencing factors that amount of pick-up and drop-off of shared e-scooter by dividing the Seoul into a 200m grid. we develop spatial auotcorrelation model such as spatial lag model, spatial error model, spatial durbin model, and spatial durbin error model in order to consider the characteristics of the aggregated data based on a specific space, and the spatial durbin error model is selected as the final model. As a result, demographic factor, land use factor, and transport facility factors have statistically significant impacts on usage of shared e-scooter. The result of this study will be used as basic data for suggesting efficient operation strategies considering the characteristics of weekday and weekend.

A Study on the Area Calculation and Spatial Composition of Medical Rehabilitation Center in the Workplace Accident Rehabilitation Hospitals (산재재활전문병원 재활센터의 규모 및 공간구성에 관한 연구)

  • Lee, Teuk-Koo;Choi, Kwang-Seok
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.14 no.2
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    • pp.3-14
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    • 2008
  • The rehabilitation for the workplace accident victims is basically aimed to get them back to their working place through the secondary care processes which have some more special and more professional rehabilitation than any others, after the primary treatments like operation in an acute hospital since the accident. They need more concentrative rehabilitation efforts according to classified injury types during the period of acute, sub-acute and convalescent. This study is for the partial research of rehabilitation hospital for workers' accident victims and presents design data which can be used for the appropriate area calculation and spatial composition. Drawing documents analysis, interviews, observation were used to examine the condition of existing rehabilitation hospitals.

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Efficient detectors for MIMO-OFDM systems under spatial correlation antenna arrays

  • Guerra, David William Marques;Fukuda, Rafael Masashi;Kobayashi, Ricardo Tadashi;Abrao, Taufik
    • ETRI Journal
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    • v.40 no.5
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    • pp.570-581
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    • 2018
  • This work analyzes the performance of implementable detectors for the multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) technique under specific and realistic operation system conditions, including antenna correlation and array configuration. A time-domain channel model was used to evaluate the system performance under realistic communication channel and system scenarios, including different channel correlation, modulation order, and antenna array configurations. Several MIMO-OFDM detectors were analyzed for the purpose of achieving high performance combined with high capacity systems and manageable computational complexity. Numerical Monte Carlo simulations demonstrate the channel selectivity effect, while the impact of the number of antennas, adoption of linear against heuristic-based detection schemes, and the spatial correlation effect under linear and planar antenna arrays are analyzed in the MIMO-OFDM context.

A Study on the Spatial Composition of Funeral Facilities of General Hospitals from User-centered Viewpoint (이용자 중심으로 본 종합병원 영안실의 공간구성에 관한 연구)

  • Kim, Hyang Tae;Lee, Jung Man
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.6 no.11
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    • pp.87-96
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    • 2000
  • With the change of funeral customs, funeral facilities in general hospitals are prevailing in recent years. In order to cope with this change, many funeral facilities are built in hospitals in significant sizes. Architectural considerations for funeral facilities are to be developed. In this research, based on the case analysis of the funeral facilities which are in operation, characteristics of spatial composition in those facilities are analyzed from the viewpoint of users and the result is organized in to a set of proposed guidelines for their space design. The analysis includes definition and classification of functional space, plan type, circulation and spatial atmosphere.

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Development of the Railroad Geotechnical Information Management System using Web GIS (Web GIS를 이용한 철도 지반정보 관리프로그램의 개발)

  • Hwang Seon-Keun;Lee Seong-Hyeok;Kim Hyun-Ki;Kim Jung-Moo
    • Proceedings of the KSR Conference
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    • 2003.05a
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    • pp.326-330
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    • 2003
  • The purpose of this study was to develop railroad geotechnical management system using Web GIS and the DB used in system included railroad informations and digital maps. Digital maps are primarily based on a topographical map(NGIS, 1:5000) and by adding digital maps(KRRI, 1:5000) and their spatial database system to NGI code layer, the management system was developed. The system was connected to geotechnical database already developed. The system was able to separate three parts which were layer choice, geotechnical information view and geotechnical analysis and it was possible to save geotechnical and spatial informations using ZEUS DB simultaneously. ZEUS/X was used for usefulness of GIS operation and by offering GUI, user interface for facility was achieved. Geotechnical and spatial informations in this system will provide basic data for plans, design and construction of railway lines in practical use.

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Spatially multiplexed volume hologram using an optical fiber (광섬유를 이용한 위치 다중화 구조의 체적 홀로그램)

  • 강용훈;김기현;이병호
    • Korean Journal of Optics and Photonics
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    • v.8 no.3
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    • pp.241-244
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    • 1997
  • A speckle pattern from an optical fiber is used for a reference beam in writing and reading a volume hologram. The photorefractive volume hologram with this scheme shows good spatial selectivity for spatial(shift) multiplexing because the speckle pattern in writing and reading a hologram looses correlation with a small spatial shift. This scheme has the insensitivity to axial movement. The data storage system with this scheme will have a high storage density and a good stability in operation. We theoretically analyze the diffracted beam from a volume hologram recorded with the speckle pattern from the optical fiber. Experimental results are presented and compared with numerical analysis.

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A Study on the Spatial Composition for Rehabilitation Hospital (재활병원 공간구성에 관한 연구)

  • Jung, Eun-Young;Lee, Teuk-Koo
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.10 no.2
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    • pp.7-18
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    • 2004
  • As a society advances and develops more rapidly, there is a corresponding increase in an aging population; and therefore, transportation and transportation needs develop in a complicated way. In these times, medical rehabilitation services are required and the demands for these services will increase as time passes. Moreover, the scope of disability as defined by the government has been expanded owing to the welfare policy for the disabled. Therefore, the number of disabled who require medical services is on the rise. Along with an increase in medical rehabilitation demands, the necessity for medical rehabilitation increases as well and its role becomes more diverse on a wider spectrum. However, architectural studies on rehabilitation facilities have been insufficient and there are many problems currently in facilities operations. This study aims to present a spatial organization system along with required space that would form the basis for the most effective spatial plan and facility operation for rehabilitation hospitals.

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