• Title/Summary/Keyword: Geographic data views

Search Result 11, Processing Time 0.023 seconds

An Object Oriented Data Model of a Spatiotemporal Geographic-Object Based on Attribute Versioning (속성 버전화에 기반한 시공간 지리-객체의 객체 지향 데이터 모델)

  • Lee, Hong-Ro
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.38 no.6
    • /
    • pp.1-17
    • /
    • 2001
  • Nowadays, spatiotemporal data models deal with objects which can be potentially useful for wide range applications in order to describe complex objects with spatial and/or temporal facilities. However, the information needed by each application usually varies, specially in the geographic information which depends on the kind of time oriented views, as defined in the modeling phase of the spatiotemporal geographic data design. To be able to deal with such diverse needs, geographic information systems must offer features that manipulate geometric, space-dependent(i.e, thematic), and spatial relationship positions with multiple time oriented views. This paper addresses problems of the formal definition of relationships among spatiotemporal objects and their properties on geographic information systems. The geographical data are divided in two main classes : geo-objects and geo-fields, which describe discrete and continuous representations of the spatial reality. I study semantics and syntax about the temporal changes of attributes and the relationship roles on geo-objects and non-geo-objects, This result will contribute on the design of object oriented spatiotemporal data model which is distinguishied from the recent geographic information system of the homogeneously anchored spatial objects

  • PDF

Visualization of Dynamic Simulation Data for Power System Stability Assessment

  • Song, Chong-Suk;Jang, Gil-Soo;Park, Chang-Hyun
    • Journal of Electrical Engineering and Technology
    • /
    • v.6 no.4
    • /
    • pp.484-492
    • /
    • 2011
  • Power system analyses, which involve the handling of massive data volumes, necessitate the use of effective visualization methods to facilitate analysis and assist the user in obtaining a clear understanding of the present state of the system. This paper introduces an interface that compensates for the limitations of the visualization modules of dynamic security assessment tools, such as PSS/e and TSAT, for power system variables including generator rotor angle and frequency. The compensation is made possible through the automatic provision of dynamic simulation data in visualized and tabular form for better data intuition, thereby considerably reducing the redundant manual operation and time required for data analysis. The interface also determines whether the generators are stable through a generator instability algorithm that scans simulation data and checks for an increase in swing or divergence. The proposed visualization methods are applied to the dynamic simulation results for contingencies in the Korean Electric Power Corporation system, and have been tested by power system researchers to verify the effectiveness of the data visualization interface.

QLGR: A Q-learning-based Geographic FANET Routing Algorithm Based on Multi-agent Reinforcement Learning

  • Qiu, Xiulin;Xie, Yongsheng;Wang, Yinyin;Ye, Lei;Yang, Yuwang
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.15 no.11
    • /
    • pp.4244-4274
    • /
    • 2021
  • The utilization of UAVs in various fields has led to the development of flying ad hoc network (FANET) technology. In a network environment with highly dynamic topology and frequent link changes, the traditional routing technology of FANET cannot satisfy the new communication demands. Traditional routing algorithm, based on geographic location, can "fall" into a routing hole. In view of this problem, we propose a geolocation routing protocol based on multi-agent reinforcement learning, which decreases the packet loss rate and routing cost of the routing protocol. The protocol views each node as an intelligent agent and evaluates the value of its neighbor nodes through the local information. In the value function, nodes consider information such as link quality, residual energy and queue length, which reduces the possibility of a routing hole. The protocol uses global rewards to enable individual nodes to collaborate in transmitting data. The performance of the protocol is experimentally analyzed for UAVs under extreme conditions such as topology changes and energy constraints. Simulation results show that our proposed QLGR-S protocol has advantages in performance parameters such as throughput, end-to-end delay, and energy consumption compared with the traditional GPSR protocol. QLGR-S provides more reliable connectivity for UAV networking technology, safeguards the communication requirements between UAVs, and further promotes the development of UAV technology.

Sports and Geography: Exploration for Spatial Approach

  • KIM, Haeyu;LEE, Hyukjin
    • Journal of Sport and Applied Science
    • /
    • v.4 no.2
    • /
    • pp.11-17
    • /
    • 2020
  • Purpose: Sports is an activity created by human beings and is related with natural and human environments, and it is a physical activity which inherently interacts with geographical properties. With the above views, it is clear that sports reflect human culture and physical environment, which are closely related to places or spaces in terms of origin, propagation and diffusion, or geography in a broader sense. This study explored the relationships between sporting activities and geography with an environmental view. Research design, data, and methodology: The study employed qualitative methodology to review the association between sport and geographical perspective. The study reviewed the broad documents including journals, periodicals, reports and so forth. Results: First, since its inception in the 1960s, research on sports geography has been steadily studied in many international geography and non-geographic research journals. Second, it reflects the distinct characteristics of the relationship between sports and geography (relationship with physical geography and humanities). Third, as a spatial approach to sports, it is the place of sports, globalization of sports, and the tourist attraction of sports. Conclusion: the findings of this study provides insights for sport geography and could be applied to the current sports industry. Further implications were discussed.

Organizational Factors Facilitating the Internationalization of Korean Franchising Companies (해외진출 국내 프랜차이즈기업의 조직특성)

  • Lim, Young-Kun;Lee, Dong-Whuy;Kim, Hee-Jung
    • Journal of Global Scholars of Marketing Science
    • /
    • v.19 no.2
    • /
    • pp.40-52
    • /
    • 2009
  • Franchising is one of the fastest growing types of business. It is already popular and well-known in the U.S., and has been growing in many other countries including Korea. Furthermore, many Korean franchising companies have expanded their business overseas actively. According to the data by the Ministry of Industry and Resource, 82 companies out of a sample of 500 franchising companies are already operating in many foreign countries and 48% of them have started their foreign business since 2006. This clearly indicates the fast growing current trend of foreign operation by Korean franchising companies. In spite of the fast growing trend of foreign expansion in the industry, academic research on internationalization of franchising companies is extremely difficult to find. Accordingly, academic research on the issue is necessary and urgent in Korea. Among the various research questions on internationalization of franchising business, this study intends to investigate the difference in organizational factors between the franchising companies doing foreign operation and those doing business only domestically. More specifically, this research has the following purposes. First, considering the lack of theoretical basis of previous studies, resource-based theory and agency theory are employed as the theoretical bases. Second, this study explains the difference in internationalization based on organizational factors such as company size, history and growth rate. Third, the five hypotheses regarding the difference in organizational factors are presented and tested empirically, which is the first attempt in the area of this topic. Finally, the study attempts to clarify the conflicting implications among theories regarding some organizational factos such as growth rate. As the theoretical background, resource-based theory and agency theory are discussed. According to resource-based theory, a firm can grow continuously when it has competence and resource, and also the ability to develop them. The competence and resource can include capital, human resource, management skill, market information, ability to manage risk, etc. Meanwhile, agency theory views the relationship between franchisor and franchisee as an agency relationship. In agency theory, bonding capability and monitoring capability are the two key factors which promote internationalization of franchising companies. Based on the two theories, a conceptual model is designed. The model consists of two groups of variables. One is organizational factors including size, history, growth rate, price bonding and geographic dispersion. The other is whether a franchising company is operating overseas or not. We developed the following five research hypotheses basically describing the relationship between organizational factors and internationalization of franchising companies. H1: The size of franchising companies operating overseas is larger than that of franchising companies operating domestically. H2: The history of franchising companies operating overseas is longer than that of franchising companies operating domestically. H3: The growth rate of franchising companies operating overseas is higher than that of franchising companies operating domestically. H4: The price bonding of franchising companies operating overseas is higher than that of franchising companies operating domestically. H5: The geographic dispersion of franchising companies operating overseas is wider than that of franchising companies operating domestically. Data for the analyses are obtained from 2005 Korea Franchise Survey data co-generated by Ministry of Industry and Resource, GS1 Korea, and Korea Franchise Association. Out of 2,804 population companies, 2,489 companies are excluded for various reasons and 315 companies are selected as the final sample. Prior to hypotheses tests, validity and reliability of the measures of size, history, growth rate and price bonding are examined for further analyses. Geographic dispersion is not validated since it is measured using nominal data. A series of independent sample T-tests is used to find out whether there exists any significant difference between the companies internationalized and those operating only domestically for each organizational factor. Among the five factors, size and geographic dispersion show significant difference, growth rate and price bonding do not reveal any difference and, finally, history factor shows conflicting results in the difference depending on how to measure it.

    shows the summary statistics for hypotheses testing. In conclusion, the results show that the size and history, which are the key variables in resource-based theory, have a significant relationship with internationalization and that geographic area, which belongs to agency theory, also has a strong relationship with internationalization. The results support the findings of extant research and, therefore, prove the usefulness of resource-based theory and agency theory in explaining internationalization of franchising companies. However, growth rate and price-bonding do not show a clear difference between the two types of companies. Accordingly, these two factors need further attention in the future research. Although this study shows meaningful findings theoretically and practically, it has several limitations. First, only organizational factors are considered even if there are various environmental factors influencing franchising firm's internationalization. Second, only being internationalized or not is considered. That is, modes of entry and the size of foreign operations are not included in the study. Third, internationalization strategy is often determined based on the desire for business expansion and higher profitability and egoistical reasons of the CEOs. However, this type of factors belonging to behavioral science is not discussed in the study. Finally, organizational ecology perspective is usefully applicable in explaining the survival and performance of internationally operating companies. Accordingly, research propositions based on this perspective need to be developed and tested.

  • PDF
  • A Restricted retransimission Mechanism for Error Recovery in a Multicast Group (멀티캐스트 그룹에서의 오류 회복을 위한 재전송 제한 기법)

    • Kim, Eun-Suk;Choe, Jong-Won
      • Journal of KIISE:Computer Systems and Theory
      • /
      • v.26 no.8
      • /
      • pp.957-965
      • /
      • 1999
    • 그룹간 공동 작업이나 화상 회의와 같은 그룹 통신의 수요가 늘어나면서 멀티캐스팅을 이용한 효율적인 데이타 전송에 대한 요구가 증가하고 있다. 특히 오디오나 비디오 데이타와는 달리 공동 문서 작업이나 그룹간 문서 전송을 위한 데이타 처리를 위해서는 어느 정도의 시간 손실이 있더라도 신뢰성을 보장할 수 있는 멀티캐스트 프로토콜이 요구된다. 그러나 멀티캐스트 전송에서의 신뢰성을 보장하기 위하여 손실 패킷에 대한 재전송 패킷이 전체 그룹으로 멀티캐스트 되는 것은 네트워크 상에 트래픽을 폭증시키는 요인이 된다. 이에 본 논문에서는 지역 그룹에서의 오류 회복을 위한 재전송 제한 기법을 제안하여 손실 패킷의 재전송 과정에서 발생하는 트래픽의 폭주를 제어하고자 한다. 이것은 재전송 패킷이 중복없이 다중 수신자에게 전송될 수 있도록 하여 그룹 내의 재전송 패킷의 양을 줄이고 필요없는 중복 패킷이 네트워크의 효율을 저하시키는 것을 방지하고자 하는 데 그 목적이 있다. Abstract As the size and the geographic span of communication groups increases, efficient data transmission schemes using Multicast service become more and more essential. Especially, unlike audio and video applications, for some collaborative applications and other data delivery components which require ordered and lossless delivery of data, Reliable Multicast Service is needed to ensure consistent presentation across multiple views. Thus error recovery by retransmission of loss data is provided in order to guarantee the reliability of multicast transmission protocol. However, redundant retransmission packets by multicast may cause traffic implosion on the Internet and it can be aggravated with continuous retransmission.This paper describes a Restricted Retransmission Mechanism as an error recovery method of multicast service in a local group, which can handle traffic implosion in retransmission process. It reduces redundant retransmission packets flowing into a local group and supports reliable multicast transmission. The goal of this mechanism is to reduce retransmission packets and decrease the load for group members and networks.

    A Phylogenetic Study in Some Long-Horned Beetles (Coleoptera: Cerambycidae) Using Mitochondrial COI Gene and 16S rRNA Sequences

    • Yoon, Hyung-Joo;Bae, Jin-Sik;Kim, Iksoo;Jin, Byung-Rae;Mah, Young-Il;Moon, Jae-Yu;Sohn, Hung-Dae
      • International Journal of Industrial Entomology and Biomaterials
      • /
      • v.2 no.1
      • /
      • pp.37-53
      • /
      • 2001
    • Two regions of mtDNA genome, cytochrome oxidase subunit I (COI) and 165 ribosomal RNA (165 rRNA) genes, were sequenced for 15 species of the long-horned beetle belonging to four subfamilies and geographic samples of mulberry longicorn beetle, Apriona germari, from two localities in Korea. Ten samples of A. germari collected from Suwon and Busan revealed three COI haplotypes ranging in nucleotide divergence of 0.3% to 0.5%, and the two populations shared one common COI haplotype (80%). The sequence divergence among 15 species of the long-horned beetle was much higher in COI gene (12.3%∼39.4%) than 16S rRNA gene (7.2% to 23.1), and the maximum value in the COI gene is exceptional compared with other relevant studies, including that of Coleoptera. The greatly increased divergence in the COI gene, in facto was stemmed from a peculiar sequence of Prionus insularis belonging to Prioninne, divergence of which ranges from 31.2% to 39.3% from other species. We discussed possible reason of the divergence in this species. Due to the abnormality of COI gene divergence, decrease in phylogenetic signal was severe in COI nucleotide and, subsequently, the converted amino acid sequences, rendering us to put more confidence on the 16S5 rRNA gene data. Although the molecular phylogeny confidently supports the monophyletic origin of Lepturinae, the presence of discrepancy between molecular data and traditional taxonomic views also is a testable hyothesis. One such discrepancy includes taxonomic position of Sophronica obrioides and Theophilea cylindricollis belonging to Lamiinae.

    • PDF

    Study on Developing Program for Efficient Landscape Woody Plants Management - Mainly Focused on the Development of a Tree Inventory System - (조경수목의 효율적 관리를 위한 프로그램 개발에 관한 연구 - 관리대장(Tree Inventory) 개발을 중심으로 -)

    • 조영환;곽행구
      • Journal of the Korean Institute of Landscape Architecture
      • /
      • v.24 no.4
      • /
      • pp.1-22
      • /
      • 1997
    • This paper was focused on the efficient management of landscape woody plants, and concerned itself with their important role in the urban environment. Based on the philosophy that there is nothing that can be done without an inventory, the purpose of this study was to develop an inventory system and iris proper application to a site for establishing a management plan Two different approaches were used, The first was to make a newly structured inventory system through collecting, analyzing, and evaluating various types of inventories used in Korea, the U. S. A., and Japan. The second approach was to apply a newly designed inventory system to the case study area. using GIS 'as a tool of spacial analysis and statistics for making decisions. The results could be summarized as follows; 1. In Korea, most of the Landscape Woozy Plants Inventories had datas which represented possession of trees, and only the work which they had done according to their traditional ways, There was no data related to the conditions, management needs, and site conditions of individual trees, This is essential information for organizing an inventory system . 2. There needs to be data which is balanced, containing tree characteristics and site characteristics. Through such information the management needs could be adjusted properly. The inventory list described in this paper was determined by botanical identity, placement condition, condition of tree, and types of work for maintaining as well as improving the condition of each tree One of the most important things was to determine the location data of each tree so as to compare data with other trees. The data gained from the field survey still had some problems because of lack of scientific method for supporting objective views, and because of actual situations, especially in the field of evaluating site conditions and management needs. All data should be revised to fit a computer data management system , if possible 3. The GIS(Geographic Information System) application showed good performance in handling inventory data for decision making. All the data used for the GIS application was divided into location and non-spatial data. Using the location data, it was easy to find the exact location of each tree on the monitor and on the maps generated by the computer even in the actual managed trite, along with various attribute data. Therefore it could be said that the entire management plan should start from data of individual trees with their exact locations, for making concrete management goals through actual budget planning.

    • PDF

    Incremental Update Methods for Adapting of Spatial Views (공간 뷰 재작성을 위한 점진적 변경 방법)

    • Ban, Chae-Hoon;Moon, Sang-Ho;Hong, Bong-Hee
      • Journal of KIISE:Databases
      • /
      • v.27 no.1
      • /
      • pp.113-128
      • /
      • 2000
    • The adaptation of spatial view is to update materialized view objects when apatial view is redefined. There are tow kinds of adaptation : incremental updates and recomputation. The incremental update changes related view objects and it is more efficient than the recomputation which evaluates redefined view defining query because spatial view is defined by spatial query including high cost spatial operator. This paper proposes the several incremental update methods according to the types of changing the definition of a spatial view. There are two kinds of incremental view adaptation : the method of using only the existing view objects and the view derivation relationship between view objects and their sources. This incremental update is achieved by updating the current materialized view objects or by inserting new materialized view objects. Spatial view adapter is implemented and tested on top of the object oriented geographic information system. This paper evaluates performance between the recomputation and incremental update method through real data.

    • PDF

    The Improvement of Evaluation System for the National Spatial Information Policy : Focused on the Comparative Analysis of NGIS Act and NSDI Act (국가공간정보화정책 평가시스템의 개선방안 : 구법과 신법의 비교분석을 중심으로)

    • Kim, Tae-Jin
      • Spatial Information Research
      • /
      • v.19 no.6
      • /
      • pp.1-10
      • /
      • 2011
    • The evaluation systems on the National Spatial Information Policy(NSIP) has been changed, since the Establishment and Use of the National Geographic Information System Act(NGIS Act, 2000) was abolished and the National Spatial Data Infrastructure Act(NSDI Act, 2009) was enacted. As compared to the NGIS Act, the policy evaluation systems for National Spatial Information are regarded as unified and centralized. However, some argue that the claim of budget and the legal feasibility of the NSIP was weakened. Given the different views on the two laws, this study aims at analyzing the changes in the evaluation system by comparing the NGIS Act and the NSDI Act. A Comparative Analysis framework is employed. The subjects of the comparative analysis are evaluation mechanism, evaluator, evaluation target and range, after-assessment utilization, and agent. In order to improve the effectiveness of the evaluation system, it is recommended that the clarification of evaluation purposes, institutional enhancement for evaluation agency, the development of evaluation indexes, the combination of top-down approach and bottom -up approach, and the increased linkage between budget and evaluation result.


    (34141) Korea Institute of Science and Technology Information, 245, Daehak-ro, Yuseong-gu, Daejeon
    Copyright (C) KISTI. All Rights Reserved.