• Title/Summary/Keyword: 공간 근접성

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An Effective Object Replacement for Spatial Database Systems (공간 데이터베이스를 위한 효율적인 객체 교체 방법)

  • Min Jun-Ki
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11b
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    • pp.115-117
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    • 2005
  • 버퍼의 효율적인 관리는 시스템의 성능과 밀접한 관련성을 가지고 있다. 따라서, 최근까지 다양한 버퍼 관리 기법들이 제안되었다. 그러나, 지금까지 알려진 기법들의 대부분은 시간 근접성만을 고려하고 있다. 그러나, 공간 데이터베이스와 같은 환경에서는 시간 근접성뿐 만 아니라, 유사한 위치에 있는 공간 객체들은 서로 같이 접근 될 가능성이 높다는 공간 근접성도 존재한다. 따라서, 본 논문에서는 공간 데이터베이스 환경에서 시간 근접성과 공간 근접성 같이 효과적으로 고려하는 버퍼 관리 기법을 제안하다. 또한, 실험을 통하여 제안 기법의 효율성을 보인다.

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An Efficient Buffer Management Technique Using Spatial and Temporal Locality (공간 시간 근접성을 이용한 효율적인 버퍼 관리 기법)

  • Min, Jun-Ki
    • The KIPS Transactions:PartD
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    • v.16D no.2
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    • pp.153-160
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    • 2009
  • Efficient buffer management is closely related to system performance. Thus, much research has been performed on various buffer management techniques. However, many of the proposed techniques utilize the temporal locality of access patterns. In spatial database environments, there exists not only the temporal locality but also spatial locality, where the objects in the recently accessed regions will be accessed again in the near future. Thus, in this paper, we present a buffer management technique, called BEAT, which utilizes both the temporal locality and spatial locality in spatial database environments. The experimental results with real-life and synthetic data demonstrate the efficiency of BEAT.

The Proximity Scheme of the Perceptual Space for Indexing The Trajectories of Tags (태그 궤적 색인을 위한 인식공간 근접성 기법)

  • Kim, Dong-Hyun;Ahn, Swng-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2140-2146
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    • 2009
  • Since tags do not have location informations, the identifiers of tags which are symbolic data are used as the location informations. Therefore, it is difficult to define the proxmity between two trajectories of tags and inefficient to process the user queries for tags. In this paper, we define the perceptual space to model the location of a tag and propose the proximity of the perceptual spaces. The proximity of the perceptual spaces is composed of the static proximity and dynamic proximity. Using the proximity of the perceptual spaces, it is possible to measure the proximity between two trajectories of tags and build the efficient indexes for tag trajectories. We evaluated the performance of the proposed proximity function for tag trajectories on the IR-tree and the $R^*$-tree.

An Efficient Buffer Management Strategy Using Spatial Locality and Temporal Locality (공간적 근접성과 시간적 근접성을 이용한 효율적인 버퍼관리법)

  • 안재용;민준기;정진완
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.04b
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    • pp.4-6
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    • 2001
  • 데이터베이스 관리시스템에서 데이터를 디스크에서 읽어오는 작업은 많은 비용을 필요로 한다. 따라서 시스템의 성능을 향상시키기 위해서는 I/O의 횟수를 최소화는 것이 가장 중요한 문제이다. 특히 공간데이터베이스 환경에서는 클라이언트 버퍼의 크기가 데이터베이스의 크기에 비해 매우 작기 때문에 버퍼를 효율적으로 사용하여 I/O 회수를 줄이는 문제는 더욱 중요하게 고려하여야 한다. 지금까지 디스크 I/O 횟수를 줄이기 위해서 많은 버퍼관리 기법들이 제안되었지만, 그 기법들은 시간적 근접성만을 고려해왔기 때문에 공간적 근접성도 존재하는 공간데이터베이스 환경에서는 최적의 성능을 보여주지 못했다. 본 논문에서는 공간 데이터베이스의 시간적 근접성과 공간적 근접성을 동시에 고려하는 새로운 버퍼관리기법인 SLM-tree Buffer Management Strategy를 제안한다. 제안한 버퍼관리기법은 공간 데이터베이스 환경에서 디스크 I/O의 횟수를 현저하게 줄임으로서 기존의 방법들에 비해 월등한 성능을 보여준다.

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SLAM : An Efficient Buffer Management Strategy using Spatial Locality of Spatial Data (SLAM : 공간 데이타의 공간적 근접성을 이용한 효율적인 버퍼관리기법)

  • An, Jae-Yong;Min, Jun-Gi;Jeong, Jin-Wan
    • Journal of KIISE:Databases
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    • v.29 no.5
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    • pp.393-403
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    • 2002
  • One of the major issues of DBMS is the buffer management. Because fetching data from the database disk is costly, the number of disk I/O's must be minimized in order to improve the DBMS performance. Although there have been many buffer management strategies to minimize the disk I/O, those strategies usually focused on just the temporal locality. Since there are the spatial locality as well as the temporal locality in the spatial database, strategies using only the temporal locality cannot achieve the optimal performance in the spatial database. In this paper, we propose a new buffer management strategy, the Spatial Locality Area Measure(SLAM) strategy, that considers not only the temporal locality but also the spatial locality. The SLAM buffer management strategy consists of two core structures, the SLM-tree and the M-LRU. We show the efficiency of the proposed strategy through experiments over various buffer sizes and reference frequencies.

An Empirical Analysis on the Technical Efficiency from the Perspective of Space Closeness in Apparel Textile Industry of Busan (부산지역 섬유·패션기업의 공간근접성에 따른 효율성 분석)

  • Joo, Soo-Hyeon;Lee, Sun-Young;Kim, Young-Jae
    • International Area Studies Review
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    • v.12 no.3
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    • pp.341-365
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    • 2008
  • This paper investigates the properties and relative importance of Apparel Textile industry of Busan in terms of both the number of employees and the value-added, and then analyzes the relative technical efficiencies from the perspectives of space closeness such as consumption market, suppliers, living standards and clustering environments using the DEA model. The main outcomes are as follows. The Apparel Textile industry is still a key industry in Busan with relatively high intensity and high LQ (greater than one) in spite of the recent decrease between 2000 and 2005 both in the number of employees and the value-added. Those firms with consumption market showed higher efficiency in all kinds of efficiencies than the firms without the market, and further relatively higher efficiency than the firms with suppliers. In addition, the firms located in the higher living standards also showed higher values of efficiency compared with the firms in lower living standards. The policy implication from the results is that the strategic and selective investment should be made according to the relative efficiency and thus the traditional industry should be transformed to the high value added one with additional investment to utilize the scale efficiency.

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 s.110
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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.

The Shifting Process of R&D Spaces in Firm's Adaptation: Competences, Learning and Proximity (기업의 적용에 있어 R&D 공간의 변화: 조직적 역량, 학습 그리고 근접성)

  • Lee, Jong-Ho
    • Journal of the Korean association of regional geographers
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    • v.8 no.4
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    • pp.529-541
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    • 2002
  • This paper aims to provide a context-specific interpretation on the shifting process of in-house R&D spaces in a large Korean firm in the context of rapidly changing markets and technology. Drawing on the case study of LG Electronics Company, one of the Korea's flagship companies, I examine the causes and mechanisms leading to a shift in domestic R&D spaces and the nature of learning processes between R&D teams and between R&D and other organizational units, particularly manufacturing. It appears that the current reshaping processes of domestic R&D spaces in LGE focus more on the clustering of core R&D laboratories than the geographical integration of conception and execution. However, it should not simply be viewed that such a move would be reduced to the linear model of innovation and organizational learning. Instead, it involves the firm-specific mode of regulating organizational competences. As contextual variables to induce such a firm-specific mode of organizational change, I consider the spatial form of organization, the spatial sources of knowledge and learning, and the powers of relational learning that can be made between distanciated actors and teams.

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A Case Study of Community without Propinquity : focused on Topgol Comic Book Space in Goesan, Chungbuk (근접성 없는 공동체의 사례 연구 - 충북 괴산 탑골 만화방을 대상으로 -)

  • Lee, Jung-Min;Lee, Man-Hyung;Hong, Sung-Ho
    • Journal of the Korean association of regional geographers
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    • v.22 no.3
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    • pp.655-665
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    • 2016
  • The meanings and roles of community have been changed. Traditional community theories hinged on the neighborhood have been threatened by the alternative concept of 'communities without propinquity'. Embracing unprecedented development of transportation, information and communication technologies, Propinquity of community has not been a precondition. This paper reviews the development of community theories with a frame of 'communities without propinquity'. Furthermore, applying social network analysis(SNA) approaches, it explores the communality of Topgol Comic Book Space, located in Goesan, Chungbuk and examines spatial characters. Visitors' networks of Topgol Comic Book Space builda up national coverage and expands. It functions as a field of testing various activities without explicit 'fixed purpose'. The case exemplifies a community, continuously enlarging the spatial and social boundaries, performing a series of activities, and connecting both the outside and the local.

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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.