• Title, Summary, Keyword: spatial proximity

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Integrating Spatial Proximity with Manifold Learning for Hyperspectral Data

  • Kim, Won-Kook;Crawford, Melba M.;Lee, Sang-Hoon
    • Korean Journal of Remote Sensing
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    • v.26 no.6
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    • pp.693-703
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    • 2010
  • High spectral resolution of hyperspectral data enables analysis of complex natural phenomena that is reflected on the data nonlinearly. Although many manifold learning methods have been developed for such problems, most methods do not consider the spatial correlation between samples that is inherent and useful in remote sensing data. We propose a manifold learning method which directly combines the spatial proximity and the spectral similarity through kernel PCA framework. A gain factor caused by spatial proximity is first modelled with a heat kernel, and is added to the original similarity computed from the spectral values of a pair of samples. Parameters are tuned with intelligent grid search (IGS) method for the derived manifold coordinates to achieve optimal classification accuracies. Of particular interest is its performance with small training size, because labelled samples are usually scarce due to its high acquisition cost. The proposed spatial kernel PCA (KPCA) is compared with PCA in terms of classification accuracy with the nearest-neighbourhood classification method.

The Performance of An Inspection System Providing 3D Spatial Proximity Data and Its' Design Considerations (3차원 근접정보를 이용한 검사시스템의 성능평가와 디자인 고려사항)

  • Jeong, Gyeong-Ho
    • Journal of the Ergonomics Society of Korea
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    • v.23 no.1
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    • pp.13-22
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    • 2004
  • Due to economical or technological reasons. humans are responsible for inspection functions in many cases. Humans. however. are rarely perfect. thus allowing non-confirming parts to be processed. As the attributes of interest or the variety of products increases. the inspection system becomes less effective because of the sensory and cognitive limitations of human inspectors. Any means that can support or aid the human inspectors is necessary to compensate for inspection difficulty. Augmented reality (AR) offers a new approach in designing an inspection system as a means to augment the cognitive capability of inspectors by providing the 3D spatial proximity between two information channels. The experimental results suggest that AR might be an effective tool that reduces inspection time without sacrificing the measuring accuracy.

A GIS-based Analysis of Spatial Patterns of Individual Accessibility: A Critical Examination of Spatial Accessibility Measures (GIS를 이용한 접근성의 공간적 패턴 분석: 공간적 접근성 측정방법에 대한 비판적 검토)

  • Kim Hyun-Mi
    • Journal of the Korean Geographical Society
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    • v.40 no.5
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    • pp.514-532
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    • 2005
  • The purpose of this study is to critically examine conventional spatial measures of individual accessibility, which are based on the notion of spatial proximity, the single reference location, and the unlinked travel model. Using space-time accessibility measures with the travel-activity diary data set of Portland Metro, US, three expectations from spatial measures on spatial patterns of individual accessibility were empirically examined: (1) does individual accessibility decrease with an increase of distance from the CBD?; (2) does the spatial pattern of accessibility resemble that of urban opportunity density pattern?; and (3) are spatial patterns of individual accessibility of different socio- demographic population groups basically similar as people in the same area share the same geographic characteristics regardless of gender, race, age, and so on? First of all, the results showed that spatial variations in individual accessibility were not directly determined by spatial proximity and opportunity density as suggested by previous accessibility measures. The spatial pattern of individual accessibility was dramatically different from that of urban opportunity density High peaks of accessibility level were found far away from the CBD and regional centers. This finding might be associated with the importance of multi-reference locations and linked travels in shaping accessibility in reality. Furthermore, this study found that spatial patterns of accessibility clearly differ between men and women. These findings suggest that access requires more than proximity, and that the interaction between person-specific space-time constraints and the consequential availability of urban opportunities in space-time renders different accessibility experiences to people even in the same region, which would be one of the key ingredients missing from conventional spatial measures of accessibility.

An Efficient Spatial Data Cache Algorithm for a Map Service in Mobile Environment (모바일 환경에서 지도 서비스를 위한 효율적인 공간 데이터 캐시 알고리즘)

  • Moon, Jin-Yong
    • Journal of Digital Contents Society
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    • v.16 no.2
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    • pp.257-262
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    • 2015
  • Recently, the interests of mobile GIS technology is increasing with the spread of wireless network, the improvement of mobile device's performances, and the growth of demands about mobile services. Providing services in a wireless environment with existing wired-based GIS solutions have many limitations such as slow communication, processing rates and screen size. In this paper, we propose a cache algorithm on client side to solve the above problems. The proposed algorithm demonstrates the performance improvement over known studies by utilizing unit time and spatial proximity. In addition, this paper conducts a performance evaluation to measure the improvement in algorithm efficiency and analyzes the results of the performance evaluation. When spatial data queries are conducted, according to our performance evaluation, hit rate has been improved over the existing algorithms.

Developing a new index to assess varicella outbreak (수두 유행을 평가하기 위한 신규 지표 개발)

  • Yang, Kiwook;Seo, Incheol
    • Yeungnam University Journal of Medicine
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    • v.34 no.2
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    • pp.222-230
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    • 2017
  • Background: Varicella is the most common infectious disease reported despite the high vaccination rate. Interventions that target humans are particularly effective for varicella because humans are its only natural host. On the other hand, the existing national varicella surveillance systems lack the information to identify an outbreak. Therefore, a new index to assess varicella outbreaks was developed. Methods: The residential addresses of 2,718 varicella cases reported in Daegu in 2016 were converted to geographic coordinates and the distances between new varicella case and previous cases within 21 days were calculated from the date analyzed. Two cases were considered to be adjacent if the distance between them was less than 1 km. Finally, a proximity index was introduced by dividing the number of adjacent cases by the number of new cases on the date analyzed. Results: First, time-series charts and scatter plots were used to verify that the proximity index reflected the spatial closeness of the different varicella cases. The proximity index is helpful in identifying outbreaks from a list of single varicella cases. In addition, in this study, a new epidemic characteristic of varicella based on the proximity index was shown. Conclusion: The proximity index introduced in this study can be used to determine the likelihood of an outbreak from a single case of varicella, and it can be embedded in a web-based national varicella surveillance system that is currently in operation.

Main Elements for the Global-Local Connectivity of Regional Industrial Clusters (지역산업 클러스터의 세계적-지방적 연결성을 위한 주요 요소들)

  • Park, Yong-Gyu;Jung, Sung-Hoon
    • Journal of the Economic Geographical Society of Korea
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    • v.15 no.4
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    • pp.642-659
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    • 2012
  • The main aim of this article is to examine theoretical issues on the 'global-local connectivity' of regional industrial cluster and regional innovation system which have been presented since the 2000s in terms of three different aspects. Firstly, the concept of 'geographical proximity' is discussed within the context of its importance for the regional industrial development by considering relationships of cluster, local buzz and global pipeline. Secondly, concepts on knowledge gatekeeper and temporary cluster are explored with respect to their role of a mediator in forming or transforming global-local connectivity. Finally, policy implications of the global-local connection are presented. Authors arguments are as follows; firstly, in order to improve regional industrial cluster on the basis of geographical proximity, relational proximity which is beyond different spatial scales has to be secured. It means that geographical convenience and inconvenience are required simultaneously for regional industrial development. Secondly, A base of the global-local connectivity is socal capital and embeddedness. Therefore, it needs to understand that relational proximity is embedded into different culture and habit at different spatial scales. Finally, within the context of the global-local connectivity, in order to overcome spatial hierarchy by the division of labor of firms, it needs to consider the complex system which is composed of vertical and horizontal hierarchy by the spatial division of labor by firms, openness and closeness of clusters, and the scope of policies' inclusion and exclusion by central and local governments.

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Post Occupancy Evaluations and Spatial Behavioral Patterns of Three Bay Unit Plans in Kyungnam Aren - focusing on $85\textrm{m}^2$ apartment units size - (경남지역의 전면 3칸형 아파트의 공간이용행태 및 거주후 평가에 관한 연구 -전용면적 $85\textrm{m}^2$를 전후하여-)

  • 김상희;안주영
    • Journal of the Korean housing association
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    • v.13 no.4
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    • pp.1-10
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    • 2002
  • The purpose of this study was to contribute to planning and developing various new apartment unit plans of the future through examining the differences on the spatial behavioral patterns and the post-occupancy evaluation between DK-front type and DK-rear type. 245 households which were included 79 DK-front types and 166 DK-rear types, were collected and analyzed at Masan and Gimhae cities in Kyungnam area. The result is as follows: 1) The analysis of the spatial behavioral patterns revealed that Anbang was the room for the couple independent from guests and children. Living room was the family's room for every activity, used more frequently DK-front types than DK-rear types. The family lift cycles of households, the visual unification between Living room and DK, the closed figures of DK in DK-front types have been influenced for the activities of Living room. 2) In the post-occupancy evaluation, DK-front types were positive in the lighting of DK area and its connection with Living room, while negative in the proximity from entrance to DK, cooking convenience, and the proximity between rooms. It was explained clearly through the reasons of the rejection of DK-front types from now.

Space Planning of the Health Life Support Center using the Modular Construction Method - Space Unitification and Modularization through Spatial Proximity Analysis of Case Projects - (모듈러 공법을 적용한 건강생활지원센터 공간계획에 관한 연구 - 기존 사례의 공간 근접도 분석을 통한 공간 유닛화와 모듈화 -)

  • Jang, Hwalje;Kwon, Nahyun;Ahn, Yonghan;Ahn, Chiwon
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.11
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    • pp.43-52
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    • 2019
  • The purpose of this study is to suggest the use of modular construction method in order to promote the dissemination of the Health Life Support Center of the government, and to suggest the modular unitification and modularization plan for the necessary space data in the initial stage. By analyzing the floor plans of the 50 case projects currently in operation, the 28 required spaces and their spatial proximities are determined. Base on spatial proximities, each space is unitificated into a modular unit and modularized into a modular modules were integrated to modular proposals. As a result of this study, 13 unitificated modular unit floor planes and 3 modularized module floor planes including the staircase unit were proposed. However, future study have needed to study how to apply them to different actual sites and how to reduce cost.

Structural Arrangement for Functional Requirements of Brain Recombinant 4-Aminobutyrate Aminotransferase

  • Sung, Bo-Kyung;Kim, Young-Tae
    • BMB Reports
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    • v.33 no.1
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    • pp.43-48
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    • 2000
  • 4-Aminobutyrate aminotransferase is a key enzyme of the 4-aminobutyric acid shunt. It converts the neurotransmitter 4-aminobutyric acid to succinic semialdehyde. In order to study the structural and functional aspects of catalytically active Cys residues of pig brain 4-aminobutyrate aminotransferase, we purified the active form in E. coli by coproduction of thioredoxin. The structural arrangement for functional requirements of a dimeric protein using a bifunctional sultbydryl reagent was then characterized, and the spatial proximity between the essential SH groups and a cofactor (pyridoxal-5'-phosphate) binding site was determined. The bifunctional sultbydryl reagent DMDS reacted with the enzyme at the ratio of one molecule per enzyme dimer. This resulted in an approximately 50% loss of enzymatic activity. The spatial proximity of the distance between the essential SH groups and the cofactor-binding site was determined by the energy transfer measurement technique. The result (approximate 20 ${\AA}$) suggested that cross-linking of two sulfhydryl groups with DMDS is not near a PLP binding site.

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An Efficient Algorithm for Mining Frequent Sequences In Spatiotemporal Data

  • Vhan Vu Thi Hong;Chi Cheong-Hee;Ryu Keun-Ho
    • 한국공간정보시스템학회:학술대회논문집
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    • pp.61-66
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    • 2005
  • Spatiotemporal data mining represents the confluence of several fields including spatiotemporal databases, machine loaming, statistics, geographic visualization, and information theory. Exploration of spatial data mining and temporal data mining has received much attention independently in knowledge discovery in databases and data mining research community. In this paper, we introduce an algorithm Max_MOP for discovering moving sequences in mobile environment. Max_MOP mines only maximal frequent moving patterns. We exploit the characteristic of the problem domain, which is the spatiotemporal proximity between activities, to partition the spatiotemporal space. The task of finding moving sequences is to consider all temporally ordered combination of associations, which requires an intensive computation. However, exploiting the spatiotemporal proximity characteristic makes this task more cornputationally feasible. Our proposed technique is applicable to location-based services such as traffic service, tourist service, and location-aware advertising service.

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