Abstract:- Bookmarks are the facilities found in current web browsers, which allow a user to revi... more Abstract:- Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con-sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma-jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta-phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark “space ” and a corresponding 3D visualization for this “space ” are sug-gested. The proposed f...
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. This paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents; the HyperText Transfer Protocol (HTTP). The so-called “user session ” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory- state) by servers. We propose an architecture for the deployment of stateful database applications in the context of c...
The phenomenal growth that the WWW currently experiences necessitates the integration of various ... more The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server-and client-side components.
The phenomenal growth that the WWW currently experi- ences necessitates the integration of variou... more The phenomenal growth that the WWW currently experi- ences necessitates the integration of various types of in- formation sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of informa- tion from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW p... more Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con- sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma- jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta- phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark "space" and a corresponding 3D visualization for this "space" are sug- gested. The...
ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of... more ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its technological platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW p... more Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con-sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma-jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta-phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark "space" and a corresponding 3D visualization for this "space" are sug-gested. The pro...
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. The paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents: the HyperText Transfer protocol (HTTP). The so-called “user session” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory state) by servers. We propose an architecture for the deployment of stateful database applications in the context of conventional WWW servers. In this architecture, state information preserved in the WWW client as well as in specialised agents that operate behind the WWW server, provides the required basis for a “session-aware” database application. The main benefits of this architecture are that it doesn't modify existing server software and requires minimum programming effort for the porting of existing “session-aware” applications to the WWW environment
ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for... more ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for the deployment of applications in wide area networks (telematics) as well as corporate intranets. Such applications are, in the majority of cases, tightly coupled with legacy databases hosted by relational management systems. However, the nature of the database enabled WWW systems is quite different from that of classical database applications developed with tools like 4GLs, Forms, Menus, etc. The basic difference lies in the stateless character of the WWW. The `user session' concept, encountered in conventional database applications, does not apply in the WWW environment. Instead, interaction with the information server is accomplished through a series of hits (request–response interactions) which are treated independently. This paper presents an architecture for the deployment of stateful database gateways for WWW servers. Although the server still treats each individual hit independently, state information maintained in the WWW browser as well as in specialized agents that operate behind the WWW server renders the WWW appropriate for a `session-aware' database application. The effort required to port an existing `session-aware' database application to the WWW environment is minimal.
Proceedings. The Twenty-Second Annual International Computer Software and Applications Conference (Compsac '98) (Cat. No.98CB 36241), 1998
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. The paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents: the HyperText Transfer protocol (HTTP). The so-called “user session” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory state) by servers. We propose an architecture for the deployment of stateful database applications in the context of conventional WWW servers. In this architecture, state information preserved in the WWW client as well as in specialised agents that operate behind the WWW server, provides the required basis for a “session-aware” database application. The main benefits of this architecture are that it doesn't modify existing server software and requires minimum programming effort for the porting of existing “session-aware” applications to the WWW environment
SMC'98 Conference Proceedings. 1998 IEEE International Conference on Systems, Man, and Cybernetics (Cat. No.98CH36218), 1998
ABSTRACT The aim of this paper is to introduce a semantic modeling architecture for hypermedia as... more ABSTRACT The aim of this paper is to introduce a semantic modeling architecture for hypermedia as well as to focus on the possibilities that emanate from it, namely dynamic linking, hypergraph clustering and querying. Aspects of a prototype system, “Platon” that incorporates the above architecture, are also discussed
Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99, 1999
The phenomenal growth that the WWW currently experiences necessitates the integration of various ... more The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server-and client-side components.
ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of... more ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its technological platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for... more ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for the deployment of applications in wide area networks (telematics) as well as corporate intranets. Such applications are, in the majority of cases, tightly coupled with legacy databases hosted by relational management systems. However, the nature of the database enabled WWW systems is quite different from that of classical database applications developed with tools like 4GLs, Forms, Menus, etc. The basic difference lies in the stateless character of the WWW. The `user session' concept, encountered in conventional database applications, does not apply in the WWW environment. Instead, interaction with the information server is accomplished through a series of hits (request–response interactions) which are treated independently. This paper presents an architecture for the deployment of stateful database gateways for WWW servers. Although the server still treats each individual hit independently, state information maintained in the WWW browser as well as in specialized agents that operate behind the WWW server renders the WWW appropriate for a `session-aware' database application. The effort required to port an existing `session-aware' database application to the WWW environment is minimal.
... Due to the fact that the SIS encodes services, altering a service in most cases simply means ... more ... Due to the fact that the SIS encodes services, altering a service in most cases simply means to update the SIS rather to re-program the application. ... This type of properties is termed write-once (wo) to distinguish from the usual (write-many) properties. ...
Abstract:- Bookmarks are the facilities found in current web browsers, which allow a user to revi... more Abstract:- Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con-sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma-jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta-phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark “space ” and a corresponding 3D visualization for this “space ” are sug-gested. The proposed f...
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. This paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents; the HyperText Transfer Protocol (HTTP). The so-called “user session ” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory- state) by servers. We propose an architecture for the deployment of stateful database applications in the context of c...
The phenomenal growth that the WWW currently experiences necessitates the integration of various ... more The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server-and client-side components.
The phenomenal growth that the WWW currently experi- ences necessitates the integration of variou... more The phenomenal growth that the WWW currently experi- ences necessitates the integration of various types of in- formation sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of informa- tion from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW p... more Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con- sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma- jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta- phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark "space" and a corresponding 3D visualization for this "space" are sug- gested. The...
ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of... more ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its technological platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW p... more Bookmarks are the facilities found in current web browsers, which allow a user to revisit a WWW page. Most WWW browsers provide a hierarchical structure for aiding bookmark organization in searchable subsets. Average users tend to create a large number of bookmarks during multiple browsing sessions and con-sequently such hierarchies quickly become complex and hard to manage. Moreover, it is questionable whether a user recalls the significance of a single bookmark in the context of his current informational needs, as the ma-jority of WWW browsers only store the title of the relevant page. As an answer to the aforementioned issues, we propose a novel system, which supports the organization of bookmarks and also suggests a 3D spatial meta-phor as a visualization technique for navigating within bookmark collections. In specific, a semantic modeling framework for shaping the bookmark "space" and a corresponding 3D visualization for this "space" are sug-gested. The pro...
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. The paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents: the HyperText Transfer protocol (HTTP). The so-called “user session” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory state) by servers. We propose an architecture for the deployment of stateful database applications in the context of conventional WWW servers. In this architecture, state information preserved in the WWW client as well as in specialised agents that operate behind the WWW server, provides the required basis for a “session-aware” database application. The main benefits of this architecture are that it doesn't modify existing server software and requires minimum programming effort for the porting of existing “session-aware” applications to the WWW environment
ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for... more ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for the deployment of applications in wide area networks (telematics) as well as corporate intranets. Such applications are, in the majority of cases, tightly coupled with legacy databases hosted by relational management systems. However, the nature of the database enabled WWW systems is quite different from that of classical database applications developed with tools like 4GLs, Forms, Menus, etc. The basic difference lies in the stateless character of the WWW. The `user session' concept, encountered in conventional database applications, does not apply in the WWW environment. Instead, interaction with the information server is accomplished through a series of hits (request–response interactions) which are treated independently. This paper presents an architecture for the deployment of stateful database gateways for WWW servers. Although the server still treats each individual hit independently, state information maintained in the WWW browser as well as in specialized agents that operate behind the WWW server renders the WWW appropriate for a `session-aware' database application. The effort required to port an existing `session-aware' database application to the WWW environment is minimal.
Proceedings. The Twenty-Second Annual International Computer Software and Applications Conference (Compsac '98) (Cat. No.98CB 36241), 1998
Nowadays, the WWW is believed to be the ideal technological platform for the introduction of onli... more Nowadays, the WWW is believed to be the ideal technological platform for the introduction of online telematic applications as well as information systems in enterprise intranets due to its wide acceptance and standardisation (W3C). In the majority of cases, the databases supporting such novel applications are hosted by RDBMSs. The paper touches upon the incompatible nature of WWW compliant database applications and classical database applications (developed with Embedded SQL/3GLs, 4GLs, etc.). The WWW is often blamed for the stateless character of one of its constituents: the HyperText Transfer protocol (HTTP). The so-called “user session” concept is not applicable in its client/server architecture. Communication between clients and servers is realised by means of fairly simple request-response interactions (“hits”) which are treated independently (without memory state) by servers. We propose an architecture for the deployment of stateful database applications in the context of conventional WWW servers. In this architecture, state information preserved in the WWW client as well as in specialised agents that operate behind the WWW server, provides the required basis for a “session-aware” database application. The main benefits of this architecture are that it doesn't modify existing server software and requires minimum programming effort for the porting of existing “session-aware” applications to the WWW environment
SMC'98 Conference Proceedings. 1998 IEEE International Conference on Systems, Man, and Cybernetics (Cat. No.98CH36218), 1998
ABSTRACT The aim of this paper is to introduce a semantic modeling architecture for hypermedia as... more ABSTRACT The aim of this paper is to introduce a semantic modeling architecture for hypermedia as well as to focus on the possibilities that emanate from it, namely dynamic linking, hypergraph clustering and querying. Aspects of a prototype system, “Platon” that incorporates the above architecture, are also discussed
Proceedings. Tenth International Workshop on Database and Expert Systems Applications. DEXA 99, 1999
The phenomenal growth that the WWW currently experiences necessitates the integration of various ... more The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server-and client-side components.
ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of... more ABSTRACT The phenomenal growth that the WWW currently experiences necessitates the integration of various types of information sources to its technological platform. We present an open, extensible multi-agent architecture, which is based on standards like XML, for the efficient retrieval of information from RDBMSs and HTML document collections. We also specify a series of protocols for achieving the synergy between a number of server- and client-side components.
ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for... more ABSTRACT The World Wide Web is currently considered as the most appropriate software platform for the deployment of applications in wide area networks (telematics) as well as corporate intranets. Such applications are, in the majority of cases, tightly coupled with legacy databases hosted by relational management systems. However, the nature of the database enabled WWW systems is quite different from that of classical database applications developed with tools like 4GLs, Forms, Menus, etc. The basic difference lies in the stateless character of the WWW. The `user session' concept, encountered in conventional database applications, does not apply in the WWW environment. Instead, interaction with the information server is accomplished through a series of hits (request–response interactions) which are treated independently. This paper presents an architecture for the deployment of stateful database gateways for WWW servers. Although the server still treats each individual hit independently, state information maintained in the WWW browser as well as in specialized agents that operate behind the WWW server renders the WWW appropriate for a `session-aware' database application. The effort required to port an existing `session-aware' database application to the WWW environment is minimal.
... Due to the fact that the SIS encodes services, altering a service in most cases simply means ... more ... Due to the fact that the SIS encodes services, altering a service in most cases simply means to update the SIS rather to re-program the application. ... This type of properties is termed write-once (wo) to distinguish from the usual (write-many) properties. ...
Uploads
Papers by Costas Petrou