Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273161
D. Chanda, Navneet Kishore, Avinash Kumar Sinha
This paper presents a new method for classification of faults based on wavelet multiresolution analysis (MRA). Daubechies eight (D-8) wavelet transforms of the three phase currents on a transmission line fed from both ends are used. The summations of the 3rd level output of MRA detail signals of current in each phase extracted from the original signals are used as the criterion for the analysis. The effects of fault distance, fault inception angle and fault impedance are also examined. Extensive simulations are carried out to generate time domain input signal using EMTP (Microtran) on a 230 kV, 200 km long line fed from both ends and simulation results show that the proposed method is a simple, effective and robust method suitable for high impedance faults also.
{"title":"Application of wavelet multiresolution analysis for classification of faults on transmission lines","authors":"D. Chanda, Navneet Kishore, Avinash Kumar Sinha","doi":"10.1109/TENCON.2003.1273161","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273161","url":null,"abstract":"This paper presents a new method for classification of faults based on wavelet multiresolution analysis (MRA). Daubechies eight (D-8) wavelet transforms of the three phase currents on a transmission line fed from both ends are used. The summations of the 3rd level output of MRA detail signals of current in each phase extracted from the original signals are used as the criterion for the analysis. The effects of fault distance, fault inception angle and fault impedance are also examined. Extensive simulations are carried out to generate time domain input signal using EMTP (Microtran) on a 230 kV, 200 km long line fed from both ends and simulation results show that the proposed method is a simple, effective and robust method suitable for high impedance faults also.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132931204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273188
M. Tewari, H. Jamadagni
In this paper, we introduce a framework to explain an adaptive call admission control for real time traffic of a wireless network in order to improve the system performance in terms of call blocking probabilities. The key contribution of the work explained in this paper constitutes the application of a transcoding scheme of the real-time voice for a call admission controller. The advantage of employing the adaptive call admission control is illustrated by the performance curve showing the reduction in the overall call blocking probability of the system. The proposed scheme attempts to supplement existing call admission control schemes, rather to replace them.
{"title":"A new call admission control scheme for real-time traffic in wireless networks","authors":"M. Tewari, H. Jamadagni","doi":"10.1109/TENCON.2003.1273188","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273188","url":null,"abstract":"In this paper, we introduce a framework to explain an adaptive call admission control for real time traffic of a wireless network in order to improve the system performance in terms of call blocking probabilities. The key contribution of the work explained in this paper constitutes the application of a transcoding scheme of the real-time voice for a call admission controller. The advantage of employing the adaptive call admission control is illustrated by the performance curve showing the reduction in the overall call blocking probability of the system. The proposed scheme attempts to supplement existing call admission control schemes, rather to replace them.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133372047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273139
M. Jacob, J. Hartnett, J. Mazierska, J. Krupka, M. Tobar
Lithium tantalate single crystal is characterized by very low thermal expansion and exhibits excellent electro-optical, piezoelectric and pyroelectric properties. We have studied the real part of relative permittivity (/spl epsi//sub r/) perpendicular to the crystal axis and the loss tangent of LiTaO/sub 3/ over the temperature range from 15 K to room temperature at a frequency of 11.4 GHz. The /spl epsi//sub r/ and tan/spl delta/ were determined by measurements of the resonance frequency and the unloaded Q-factor of a TE/sub 011/ mode cylindrical cavity containing the sample under test. The permittivity of LiTaO/sub 3/ was found to change from 38.9 to 41.1 and the loss tangent increased from 1.1 /spl times/ 10/sub -4/ to 6.5 /spl times/ 10/sub -4/ over the temperature range from 15 K to 295 K. Due to the low losses and high permittivity this material can be used in many microwave applications.
{"title":"Lithium tantalate - a high permittivity dielectric material for microwave communication systems","authors":"M. Jacob, J. Hartnett, J. Mazierska, J. Krupka, M. Tobar","doi":"10.1109/TENCON.2003.1273139","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273139","url":null,"abstract":"Lithium tantalate single crystal is characterized by very low thermal expansion and exhibits excellent electro-optical, piezoelectric and pyroelectric properties. We have studied the real part of relative permittivity (/spl epsi//sub r/) perpendicular to the crystal axis and the loss tangent of LiTaO/sub 3/ over the temperature range from 15 K to room temperature at a frequency of 11.4 GHz. The /spl epsi//sub r/ and tan/spl delta/ were determined by measurements of the resonance frequency and the unloaded Q-factor of a TE/sub 011/ mode cylindrical cavity containing the sample under test. The permittivity of LiTaO/sub 3/ was found to change from 38.9 to 41.1 and the loss tangent increased from 1.1 /spl times/ 10/sub -4/ to 6.5 /spl times/ 10/sub -4/ over the temperature range from 15 K to 295 K. Due to the low losses and high permittivity this material can be used in many microwave applications.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133576851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273154
P. Jain, S. Pal, V. M. Pandharipande
Remote sensing satellites transmit imaging data using PSK modulation schemes with very wide range of data rates. Continuous on-line monitoring and measurement of energy-per-bit to noise-density (E/sub b//N/sub o/) ratios received during a satellite-pass become essential to perform the real time data quality analysis [Jain, P.K. et al., March 2003]. The real time estimation of E/sub b//N/sub o/ is also useful during the initial phase of the mission, i.e.. immediately after the launch of the satellite and switching on the payloads as the level fluctuations, if any, can be analyzed properly. Besides, the link analysis and practical assessment of the link margins are essential to optimize the receive chain parameters for real time compatibility [Limaye, U.D., October 1993]. This paper describes various methods to carry out this measurement with an emphasis on a unique technique developed in National Remote Sensing Agency. Dept. of Space. Govt. of India, Hyderabad. This technique uses a long loop PLL carrier recovery circuit of a multi-mission PSK demodulator and is found superior over other methods on several counts. The method has been tested for various PSK schemes at different data rates and implemented successfully in a remote sensing satellite ground station.
{"title":"Continuous measurement and monitoring of E/sub b//N/sub o/ ratio received during a remote sensing satellite-pass at a multi-mission ground station","authors":"P. Jain, S. Pal, V. M. Pandharipande","doi":"10.1109/TENCON.2003.1273154","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273154","url":null,"abstract":"Remote sensing satellites transmit imaging data using PSK modulation schemes with very wide range of data rates. Continuous on-line monitoring and measurement of energy-per-bit to noise-density (E/sub b//N/sub o/) ratios received during a satellite-pass become essential to perform the real time data quality analysis [Jain, P.K. et al., March 2003]. The real time estimation of E/sub b//N/sub o/ is also useful during the initial phase of the mission, i.e.. immediately after the launch of the satellite and switching on the payloads as the level fluctuations, if any, can be analyzed properly. Besides, the link analysis and practical assessment of the link margins are essential to optimize the receive chain parameters for real time compatibility [Limaye, U.D., October 1993]. This paper describes various methods to carry out this measurement with an emphasis on a unique technique developed in National Remote Sensing Agency. Dept. of Space. Govt. of India, Hyderabad. This technique uses a long loop PLL carrier recovery circuit of a multi-mission PSK demodulator and is found superior over other methods on several counts. The method has been tested for various PSK schemes at different data rates and implemented successfully in a remote sensing satellite ground station.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133334743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273133
J. Sanubari
This paper presents a method to improve the performance of reduced calculation adaptive filters. We use the sequential partial update method to achieve low computation complexity. Furthermore, we include the variable step-size approach to aim last convergence. The variable step size approach is based on a fuzzy method to determine the appropriate step-size on each iteration step. By using the proposed method, the adaptive filter converges faster while pretending the steady state error as the previously proposed reduced calculation adaptive filler. The instantaneous step size is determined from the present square of the error signal to produce sudden changing. Additional rule or conditions are included to prevent the adaptive algorithm to become unstable. Simulation results are presented to compare the performance of the new approach, the fixed step-size LMS algorithm and sequential partial update LMS (S-LMS) algorithms.
{"title":"Fast convergence LMS adaptive filters employing fuzzy partial updates","authors":"J. Sanubari","doi":"10.1109/TENCON.2003.1273133","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273133","url":null,"abstract":"This paper presents a method to improve the performance of reduced calculation adaptive filters. We use the sequential partial update method to achieve low computation complexity. Furthermore, we include the variable step-size approach to aim last convergence. The variable step size approach is based on a fuzzy method to determine the appropriate step-size on each iteration step. By using the proposed method, the adaptive filter converges faster while pretending the steady state error as the previously proposed reduced calculation adaptive filler. The instantaneous step size is determined from the present square of the error signal to produce sudden changing. Additional rule or conditions are included to prevent the adaptive algorithm to become unstable. Simulation results are presented to compare the performance of the new approach, the fixed step-size LMS algorithm and sequential partial update LMS (S-LMS) algorithms.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"9 21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127397725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273405
S. Vanka, M. J. Dehghani, R. Aravind, K. Prabhu
We describe a class of reduced complexity IIR cosine modulated filter banks satisfying the perfect reconstruction property. They are shown to be easy to implement, in terms of the number of filters, both on the analysis and on the synthesis sides. We provide closed-form expressions for the polyphase components of the synthesis prototype in terms of those of the analysis prototype. We also derive an expression for the frame ratio for this class of filter banks.
{"title":"A class of M-channel reduced complexity IIR cosine modulated filter banks","authors":"S. Vanka, M. J. Dehghani, R. Aravind, K. Prabhu","doi":"10.1109/TENCON.2003.1273405","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273405","url":null,"abstract":"We describe a class of reduced complexity IIR cosine modulated filter banks satisfying the perfect reconstruction property. They are shown to be easy to implement, in terms of the number of filters, both on the analysis and on the synthesis sides. We provide closed-form expressions for the polyphase components of the synthesis prototype in terms of those of the analysis prototype. We also derive an expression for the frame ratio for this class of filter banks.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114558745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273411
A. Ganguli, Sukumar Nandi, P. K. Meher
An important issue in reliable multicasting in ad hoc networks is busty packet loss that arises when a link breaks due to node mobility. For a high data rate, a multicast receiver may miss a large number of packets until the route is reestablished, and recovering from such a loss may impose a huge overhead on the bandwidth-constrained ad hoc network. By the time a node detects loss, the requested data packets may no longer be available with other nodes, which only have a limited cache size. In on demand multicast routing protocol (ODMRP), the source periodically initiates a mechanism for multicast tree creation, through join queries. It is possible that a link goes down because of node mobility, and a member stops receiving data packets, until the next join query is received. In this work, we present an explicit join scheme for ODMRP, which allows a node to reconnect to the multicast tree through an alternative path, if the existing path goes down. The scheme has been simulated on global mobile simulator (GloMoSim), and has shown to be effective in removing the busty data losses due to link failures.
{"title":"An improvement of ODMRP for reliable delivery of busty traffic","authors":"A. Ganguli, Sukumar Nandi, P. K. Meher","doi":"10.1109/TENCON.2003.1273411","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273411","url":null,"abstract":"An important issue in reliable multicasting in ad hoc networks is busty packet loss that arises when a link breaks due to node mobility. For a high data rate, a multicast receiver may miss a large number of packets until the route is reestablished, and recovering from such a loss may impose a huge overhead on the bandwidth-constrained ad hoc network. By the time a node detects loss, the requested data packets may no longer be available with other nodes, which only have a limited cache size. In on demand multicast routing protocol (ODMRP), the source periodically initiates a mechanism for multicast tree creation, through join queries. It is possible that a link goes down because of node mobility, and a member stops receiving data packets, until the next join query is received. In this work, we present an explicit join scheme for ODMRP, which allows a node to reconnect to the multicast tree through an alternative path, if the existing path goes down. The scheme has been simulated on global mobile simulator (GloMoSim), and has shown to be effective in removing the busty data losses due to link failures.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"150 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116352078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273427
P. Ramasubramanian, A. Kannan
In this paper, we present a technique that can efficiently identify anomalous accesses to the database by using an authorization rule system which has been designed for implementing a user dynamic access control system which will secure inter-operation of independently managed database services in an open, distributed environment. Traditional authorization models do not adequately meet access control requirements typical to databases, a separate authorization rule subsystem has been designed which is based on temporal event matching language (TEML). The rule specified in this security system is in event-time-condition-action (ETCA) format. XML is used for defining the authorization rules and the security rules. We could extract XML access control data from several platforms and represent the access control data for the entire enterprise through a common model. Similarly, access control data under an enterprise model can be translated to ones that are native to the platforms.
{"title":"An active rule based approach to database security in e-commerce systems using temporal constraints","authors":"P. Ramasubramanian, A. Kannan","doi":"10.1109/TENCON.2003.1273427","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273427","url":null,"abstract":"In this paper, we present a technique that can efficiently identify anomalous accesses to the database by using an authorization rule system which has been designed for implementing a user dynamic access control system which will secure inter-operation of independently managed database services in an open, distributed environment. Traditional authorization models do not adequately meet access control requirements typical to databases, a separate authorization rule subsystem has been designed which is based on temporal event matching language (TEML). The rule specified in this security system is in event-time-condition-action (ETCA) format. XML is used for defining the authorization rules and the security rules. We could extract XML access control data from several platforms and represent the access control data for the entire enterprise through a common model. Similarly, access control data under an enterprise model can be translated to ones that are native to the platforms.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129578691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273303
V. Kiran, P. Bora
We propose a new segmentation technique by integrating the active contour (snake) and the watershed algorithms. The two distinct techniques for image segmentation are combined in a manner which utilizes the strengths of both. Objects obtained by the watershed transform lack the smoothness of those obtained by contours. The accuracy of active contours, on the other hand, depends upon contour initialization around each object of interest. A new segmentation technique is proposed to eliminate the problems encountered by each method. The watershed-based segmentation on a down-sampled image is used to get the initial contours for the active contour models. The proposed integration incorporates control of smoothness in watershed, makes active contours unsupervised and prevents the snake from getting trapped in local minima.
{"title":"Watersnake: integrating the watershed and the active contour algorithms","authors":"V. Kiran, P. Bora","doi":"10.1109/TENCON.2003.1273303","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273303","url":null,"abstract":"We propose a new segmentation technique by integrating the active contour (snake) and the watershed algorithms. The two distinct techniques for image segmentation are combined in a manner which utilizes the strengths of both. Objects obtained by the watershed transform lack the smoothness of those obtained by contours. The accuracy of active contours, on the other hand, depends upon contour initialization around each object of interest. A new segmentation technique is proposed to eliminate the problems encountered by each method. The watershed-based segmentation on a down-sampled image is used to get the initial contours for the active contour models. The proposed integration incorporates control of smoothness in watershed, makes active contours unsupervised and prevents the snake from getting trapped in local minima.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129606372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2003-10-15DOI: 10.1109/TENCON.2003.1273430
Subhansu Bandopadhyay, Arindam Ghosh, Rana Sarkar
In distributed GIS (geographical information system), all locations that store data are networked together and queries gain their results from any number of locations. The queries, which can be both spatial, and a spatial can be fired from any location in the network and the result is obtained by combining disseminated information across various repositories of data [K. Buchler and L. McKee, 1996]. The proposed model of the distributed GIS will demonstrate many of the important user requirements, design concepts and relevant technologies for real world, remote archives and access capabilities and how these can be integrated into a multi-level user environment. This paper discusses the issues involved in implementing a distributed system that provides a computational infrastructure for the development of decision support and research applications requiring access to and manipulation of large geospatial data sets such as satellite imagery, from remote servers. We give an overview of some of the components of the prototype systems we have developed. The approach used here is particularly useful if the amount of data to be processed is very large (for example multiple channels of a satellite image) but the final result is relatively small (for example a processed satellite image of a localized area or perhaps just a few numbers such as average sea temperature or percentage cloud cover). This project integrates high performance computers and mass data stores to provide useful services to Web based clients for decision support applications including environmental analysis for agricultural planning and land management, analysis of satellite and photoreconnaissance images for defense command and control etc. The end users will thus be able to make the transition from traditional DSSs (decision support systems) based on manual processing of non electronic data such as maps to information age decision systems based on automated or semi automated processing of digital data from large online data archives. There is an emerging need for distributed GIS. The objective of this work is to provide models, methods, tools and frameworks for the development of open distributed geographical information systems and to apply them in at least one test case, to demonstrate and validate the usability and viability of the results. The commercial objective is to decrease the cost of geodata management and further increase the ROI (return on investment) of geodata collection and establishment. The approach is to apply the emerging reference model of open distributed processing standard in combination with existing distributed object technology in the application domain of distributed GIS. The results from this project will be a validation and demonstration of open distributed processing, based on distributed object technology, applied to GIS. The results will be used to increase the share of research and development projects in the area of GIS.
{"title":"Design of an efficient distributed GIS application","authors":"Subhansu Bandopadhyay, Arindam Ghosh, Rana Sarkar","doi":"10.1109/TENCON.2003.1273430","DOIUrl":"https://doi.org/10.1109/TENCON.2003.1273430","url":null,"abstract":"In distributed GIS (geographical information system), all locations that store data are networked together and queries gain their results from any number of locations. The queries, which can be both spatial, and a spatial can be fired from any location in the network and the result is obtained by combining disseminated information across various repositories of data [K. Buchler and L. McKee, 1996]. The proposed model of the distributed GIS will demonstrate many of the important user requirements, design concepts and relevant technologies for real world, remote archives and access capabilities and how these can be integrated into a multi-level user environment. This paper discusses the issues involved in implementing a distributed system that provides a computational infrastructure for the development of decision support and research applications requiring access to and manipulation of large geospatial data sets such as satellite imagery, from remote servers. We give an overview of some of the components of the prototype systems we have developed. The approach used here is particularly useful if the amount of data to be processed is very large (for example multiple channels of a satellite image) but the final result is relatively small (for example a processed satellite image of a localized area or perhaps just a few numbers such as average sea temperature or percentage cloud cover). This project integrates high performance computers and mass data stores to provide useful services to Web based clients for decision support applications including environmental analysis for agricultural planning and land management, analysis of satellite and photoreconnaissance images for defense command and control etc. The end users will thus be able to make the transition from traditional DSSs (decision support systems) based on manual processing of non electronic data such as maps to information age decision systems based on automated or semi automated processing of digital data from large online data archives. There is an emerging need for distributed GIS. The objective of this work is to provide models, methods, tools and frameworks for the development of open distributed geographical information systems and to apply them in at least one test case, to demonstrate and validate the usability and viability of the results. The commercial objective is to decrease the cost of geodata management and further increase the ROI (return on investment) of geodata collection and establishment. The approach is to apply the emerging reference model of open distributed processing standard in combination with existing distributed object technology in the application domain of distributed GIS. The results from this project will be a validation and demonstration of open distributed processing, based on distributed object technology, applied to GIS. The results will be used to increase the share of research and development projects in the area of GIS.","PeriodicalId":405847,"journal":{"name":"TENCON 2003. Conference on Convergent Technologies for Asia-Pacific Region","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128932841","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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