2003
Conference article
Restricted
Hybrid Parallelization of a Compact Genetic Algorithm
Hidalgo J. I., Prieto M., Lanchares J., Baraglia R., Tirado F., Garnica O.
Genetic Algorithms (GAs) are stochastic optimization heuristics in which searches in solution space are carried out by imitating the population genetics stated in Darwin's theory of evolution. We have focused this work on compact Genetic Algorithms (cGAs), which unlike standard GAs do not manage a population of solutions but only mimics its existence. In this paper we have studied several approaches that can be used to implement parallel cGAs in order to reduce the execution times and to improve the quality of the solutions reached by increasing population sizes. The parallelization models adopted to implement GAs can be classified as: centralized, global, fine grained and coarse grained. For a cGA only the two first models can be applied. Our approach consists in an hybrid model which combines both centralized and global implementations. The cGA incorporates a local search method and has been applied for solving a graph-partitioning problem for solving the Multi-FPGA systems partitioning and placement.Source: 11th Euromicro Conference on Parallel, Distributed and Network-Based Processing, pp. 449–455, Genova, 5-7 Februrary 2003
DOI: 10.1109/empdp.2003.1183624
Metrics:
Hidalgo J. I., Prieto M., Lanchares J., Baraglia R., Tirado F., Garnica O.
Genetic Algorithms (GAs) are stochastic optimization heuristics in which searches in solution space are carried out by imitating the population genetics stated in Darwin's theory of evolution. We have focused this work on compact Genetic Algorithms (cGAs), which unlike standard GAs do not manage a population of solutions but only mimics its existence. In this paper we have studied several approaches that can be used to implement parallel cGAs in order to reduce the execution times and to improve the quality of the solutions reached by increasing population sizes. The parallelization models adopted to implement GAs can be classified as: centralized, global, fine grained and coarse grained. For a cGA only the two first models can be applied. Our approach consists in an hybrid model which combines both centralized and global implementations. The cGA incorporates a local search method and has been applied for solving a graph-partitioning problem for solving the Multi-FPGA systems partitioning and placement.Source: 11th Euromicro Conference on Parallel, Distributed and Network-Based Processing, pp. 449–455, Genova, 5-7 Februrary 2003
DOI: 10.1109/empdp.2003.1183624
Metrics:
See at:
doi.org 
| link.springer.com | CNR ExploRA
1983
Other
Unknown
See at: CNR ExploRA
2005
Journal article
Open Access
A static mapping heuristics to map parallel applications to heterogeneous computing systems
Baraglia R., Ferrini R., Ritrovato P.
In order to minimize the execution time of a parallel application running on a heterogeneously distributed computing system, an appropriate mapping scheme is needed to allocate the application tasks to the processors . The general problem of mapping tasks to machines is a well known NP-hard problem and several heuristics have been proposed to approximate its optimal solution. In this paper we propose a static graph-based mapping algorithm, called Heterogeneous Multi-phase Mapping (HMM), that permits suboptimal mapping of a parallel application onto a heterogeneous computing distributed system by using a local search technique together with a tabu search meta-heuristic. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application, and considering an affinity parameter, that identifies which machine in the HC system is most suitable for executing a task. We compare HMM with four different leading techniques and with an exhaustive mapping algorithm. We also give an example of mapping of two real applications using HMM. Experimental results show that HMM performs well demonstrating the applicability of our approach.Source: Concurrency and computation 17 (2005): 1579–1605. doi:10.1002/cpe.902
DOI: 10.1002/cpe.902
Metrics:
Baraglia R., Ferrini R., Ritrovato P.
In order to minimize the execution time of a parallel application running on a heterogeneously distributed computing system, an appropriate mapping scheme is needed to allocate the application tasks to the processors . The general problem of mapping tasks to machines is a well known NP-hard problem and several heuristics have been proposed to approximate its optimal solution. In this paper we propose a static graph-based mapping algorithm, called Heterogeneous Multi-phase Mapping (HMM), that permits suboptimal mapping of a parallel application onto a heterogeneous computing distributed system by using a local search technique together with a tabu search meta-heuristic. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application, and considering an affinity parameter, that identifies which machine in the HC system is most suitable for executing a task. We compare HMM with four different leading techniques and with an exhaustive mapping algorithm. We also give an example of mapping of two real applications using HMM. Experimental results show that HMM performs well demonstrating the applicability of our approach.Source: Concurrency and computation 17 (2005): 1579–1605. doi:10.1002/cpe.902
DOI: 10.1002/cpe.902
Metrics:
See at:
Concurrency and Computation Practice and Experience 
| dl.acm.org | Concurrency and Computation Practice and Experience | CNR ExploRA
2006
Journal article
Unknown
HMM: a static mapping algorithm to map parallel applications on grids
Baraglia R., Ferrini R., Ritrovato P.
In this paper we present a static mapping heuristic, called Heterogeneous Multi-phase Mapping (HMM), which allows a suboptimal mapping of a parallel program onto a metacomputer to minimize the program execution time. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application. Moreover, it uses a local search technique together with the tabu search meta-heuristic. The experimental results show that the proposed approach performs well promising a significant potential to develop efficient mapping solutions for metacomputers.Source: Lecture notes in computer science 3911 (2006): 731–740.
Baraglia R., Ferrini R., Ritrovato P.
In this paper we present a static mapping heuristic, called Heterogeneous Multi-phase Mapping (HMM), which allows a suboptimal mapping of a parallel program onto a metacomputer to minimize the program execution time. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application. Moreover, it uses a local search technique together with the tabu search meta-heuristic. The experimental results show that the proposed approach performs well promising a significant potential to develop efficient mapping solutions for metacomputers.Source: Lecture notes in computer science 3911 (2006): 731–740.
See at: CNR ExploRA
2007
Journal article
Restricted
Dynamic personalization of Web sites without user intervention
Baraglia R., Silvestri F.
The Web is an integral part of today's busi- ness dealings. Companies and institutions exploit the Web to conduct their business; customers make daily use of the Net to per- form all kinds of transactions. In addition, most users browse through pages of per- sonal interest. The Web, as we know, is massive and its data collected from count- less sources. Consequently, search tools should be able to accurately extract, filter, and select what is "hidden" from such tools.Source: Communications of the ACM 50 (2007): 63–67. doi:10.1145/1216016.1216022
DOI: 10.1145/1216016.1216022
Metrics:
Baraglia R., Silvestri F.
The Web is an integral part of today's busi- ness dealings. Companies and institutions exploit the Web to conduct their business; customers make daily use of the Net to per- form all kinds of transactions. In addition, most users browse through pages of per- sonal interest. The Web, as we know, is massive and its data collected from count- less sources. Consequently, search tools should be able to accurately extract, filter, and select what is "hidden" from such tools.Source: Communications of the ACM 50 (2007): 63–67. doi:10.1145/1216016.1216022
DOI: 10.1145/1216016.1216022
Metrics:
See at:
dl.acm.org | Communications of the ACM | CNR ExploRA
2003
Conference article
Unknown
Multi-FPGA Systems Synthesis by Means of Evolutionary Computation
Hidalgo J. I., Fernández F., Lanchares J., Sánchez J. M., Hermida R., Tomassini M., Baraglia R., Perego R., Garnica O.
Multi-FPGA systems (MFS) are used for a great variety of applications, for instance, dynamically re-configurable hardware applications, digital circuit emulation, and numerical computation. There are a great variety of boards for MFS implementation. In this paper a methodology for MFS design is presented. The techniques used are evolutionary programs and they solve all of the design tasks (partitioning placement and routing). Firstly a hybrid compact genetic algorithm solves the partitioning problem and then genetic programming is used to obtain a solution for the two other tasks.Source: Genetic and Evolutionary Computing COmputing (GECCO 2003), pp. 2109–2120, Chicago, 12-16 July 2003
Hidalgo J. I., Fernández F., Lanchares J., Sánchez J. M., Hermida R., Tomassini M., Baraglia R., Perego R., Garnica O.
Multi-FPGA systems (MFS) are used for a great variety of applications, for instance, dynamically re-configurable hardware applications, digital circuit emulation, and numerical computation. There are a great variety of boards for MFS implementation. In this paper a methodology for MFS design is presented. The techniques used are evolutionary programs and they solve all of the design tasks (partitioning placement and routing). Firstly a hybrid compact genetic algorithm solves the partitioning problem and then genetic programming is used to obtain a solution for the two other tasks.Source: Genetic and Evolutionary Computing COmputing (GECCO 2003), pp. 2109–2120, Chicago, 12-16 July 2003
See at: CNR ExploRA
2002
Journal article
Unknown
Metay: a Web-based metacomputing problem-solving environment for building complex applications
Baraglia R., Laforenza D.
In this article we describe the main features of Meta , a software tool developed at CNUCE-CNR to build PSEs for the execution of complex applications on a Web-based metacomputer. This tool is designed to supply a completely transparent support to the user, who thus does not need to be aware of the location and the allocation of computing resources.Source: ERCIM news 45 (2002): 21–22.
Baraglia R., Laforenza D.
In this article we describe the main features of Meta , a software tool developed at CNUCE-CNR to build PSEs for the execution of complex applications on a Web-based metacomputer. This tool is designed to supply a completely transparent support to the user, who thus does not need to be aware of the location and the allocation of computing resources.Source: ERCIM news 45 (2002): 21–22.
See at: CNR ExploRA
2004
Conference article
Restricted
An online recommender system for large Web sites
Baraglia R., Silvestri F.
In this paper we propose a WUM recommender system, called SUGGEST 3.0, that dynamically generates links to pages that have not yet been visited by a user and might be of his potential interest. Differently from the recommender systems proposed so far, SUGGEST 3.0 does not make use of any off-line component, and is able to manage Web sites made up of pages dynamically generated. To this purpose SUGGEST 3.0 incrementally builds and maintains historical information by means of an incremental graph partitioning algorithm, requiring no off-line component. The main innovation proposed here is a novel strategy that can be used to manage large Web sites. Experiments, conducted in order to evaluate SUGGEST 3.0 performance, demonstrated that our system is able to anticipate users' requests that will be made farther in the future, introducing a limited overhead on the Web server activity.Source: IEEE/WIC/ACM International Conference on WEB Intelligence - WI'2004, pp. 199–205, Beijing, China, 20-24 September 2004
DOI: 10.1109/wi.2004.10158
Metrics:
Baraglia R., Silvestri F.
In this paper we propose a WUM recommender system, called SUGGEST 3.0, that dynamically generates links to pages that have not yet been visited by a user and might be of his potential interest. Differently from the recommender systems proposed so far, SUGGEST 3.0 does not make use of any off-line component, and is able to manage Web sites made up of pages dynamically generated. To this purpose SUGGEST 3.0 incrementally builds and maintains historical information by means of an incremental graph partitioning algorithm, requiring no off-line component. The main innovation proposed here is a novel strategy that can be used to manage large Web sites. Experiments, conducted in order to evaluate SUGGEST 3.0 performance, demonstrated that our system is able to anticipate users' requests that will be made farther in the future, introducing a limited overhead on the Web server activity.Source: IEEE/WIC/ACM International Conference on WEB Intelligence - WI'2004, pp. 199–205, Beijing, China, 20-24 September 2004
DOI: 10.1109/wi.2004.10158
Metrics:
See at:
ieeexplore.ieee.org | xplorestaging.ieee.org | CNR ExploRA
2004
Conference article
Unknown
An online recommender system
Baraglia R., Silvestri F.
One of the most important class of Data Mining applications is the so called 'Web Mining Systems' which analyzes and extracts important and non-trivial knowledge from Web related data. Typical applications of Web Mining are represented by the personalization or recommender systems. These systems are aimed to extract knowledge from the analysis of historical information of a web server in order to improve the web site expressiveness in terms of readability and content availability. Typically, these systems are made up of two parts. One, which is usually executed off-line, analyzes the server access logs in order to find a suitable categorization, and another, which is usually executed online, classifies the active requests, according to the previous off-line analysis. In this paper we propose SUGGEST 2.0 a recommender system which differently from previously proposed WUM systems does not make use of an off-line component. Moreover, in the last part of the paper, we analyze the quality of the generated suggestions and the performance of our solution. To this purpose we also introduce a new quality metric which try to estimate the effectiveness of a recommender system as the capacity to anticipate users' requests that will be issued farther in the future.Source: Twelfth Italian Symposium on Advanced Database Systems, pp. 130–141, S. Margherita di Pula, Cagliari, 21-23 June 2004
Baraglia R., Silvestri F.
One of the most important class of Data Mining applications is the so called 'Web Mining Systems' which analyzes and extracts important and non-trivial knowledge from Web related data. Typical applications of Web Mining are represented by the personalization or recommender systems. These systems are aimed to extract knowledge from the analysis of historical information of a web server in order to improve the web site expressiveness in terms of readability and content availability. Typically, these systems are made up of two parts. One, which is usually executed off-line, analyzes the server access logs in order to find a suitable categorization, and another, which is usually executed online, classifies the active requests, according to the previous off-line analysis. In this paper we propose SUGGEST 2.0 a recommender system which differently from previously proposed WUM systems does not make use of an off-line component. Moreover, in the last part of the paper, we analyze the quality of the generated suggestions and the performance of our solution. To this purpose we also introduce a new quality metric which try to estimate the effectiveness of a recommender system as the capacity to anticipate users' requests that will be issued farther in the future.Source: Twelfth Italian Symposium on Advanced Database Systems, pp. 130–141, S. Margherita di Pula, Cagliari, 21-23 June 2004
See at: CNR ExploRA
2005
Conference article
Unknown
Medical imaging demonstrator on a distributed virtual organisation
Baraglia R, Demi M., Di Bona S., Fontanelli R., Guerri D., Salvetti O.
In several fields of the healthcare, there is a wide use of imaging techniques for diagnostic purposes, which usually lead to the acquisition of large sequences of images that are not easily analysed by the experts. The automatic processing of the events monitored represents an important support for the diagnosis. In this paper, we present a distributed decision support system for image classification based on neural networks. The applications presented are multidisciplinary, computational intensive and component based; therefore, a virtual organisation exploiting the GRID paradigm has been introduced in order to guarantee good performances of the diagnostic procedure and reliable results.Source: 2nd International Conference on Computational Intelligence in Medicine and Healthcare (CIMED 2005), pp. 410–417, Lisbon, 29 june - 1 july 2005
Baraglia R, Demi M., Di Bona S., Fontanelli R., Guerri D., Salvetti O.
In several fields of the healthcare, there is a wide use of imaging techniques for diagnostic purposes, which usually lead to the acquisition of large sequences of images that are not easily analysed by the experts. The automatic processing of the events monitored represents an important support for the diagnosis. In this paper, we present a distributed decision support system for image classification based on neural networks. The applications presented are multidisciplinary, computational intensive and component based; therefore, a virtual organisation exploiting the GRID paradigm has been introduced in order to guarantee good performances of the diagnostic procedure and reliable results.Source: 2nd International Conference on Computational Intelligence in Medicine and Healthcare (CIMED 2005), pp. 410–417, Lisbon, 29 june - 1 july 2005
See at: CNR ExploRA
2001
Conference article
Unknown
A parallel compact genetic algorithm for multi-FPGA partitioning
Hidalgo J. I., Baraglia R. Perego R., Lanchares J., Tirade F.
In this paper we investigate the design of a compact genetic algorithm to solve Multi-FPGA Partitioning problems. Nowadays Multi-FPGA systems are used for a great variety of applications such as dynamically re-configurable hardware applications, digital circuit emulation, and numerical computation. Both a sequential and a parallel version of a compact genetic algorithm (cGA) have been designed and implemented on a cluster of workstations. The peculiarities of the cGA permits to save memory in order to address large Multi-FPGA Parfitioning problems, while the exploitation of parallelism allows to reduce execution times. The good results achieved on several experiments conduced on different Multi-FPGA Partitioning instances show that this solution is viable to solve Multi-FPGA Partitioning problems.Source: Euromicro Workshop on Parallel and Distributed Processing, pp. 113–120, Mantova, Italy, 2001
Hidalgo J. I., Baraglia R. Perego R., Lanchares J., Tirade F.
In this paper we investigate the design of a compact genetic algorithm to solve Multi-FPGA Partitioning problems. Nowadays Multi-FPGA systems are used for a great variety of applications such as dynamically re-configurable hardware applications, digital circuit emulation, and numerical computation. Both a sequential and a parallel version of a compact genetic algorithm (cGA) have been designed and implemented on a cluster of workstations. The peculiarities of the cGA permits to save memory in order to address large Multi-FPGA Parfitioning problems, while the exploitation of parallelism allows to reduce execution times. The good results achieved on several experiments conduced on different Multi-FPGA Partitioning instances show that this solution is viable to solve Multi-FPGA Partitioning problems.Source: Euromicro Workshop on Parallel and Distributed Processing, pp. 113–120, Mantova, Italy, 2001
See at: CNR ExploRA
2001
Conference article
Open Access
A parallel hybrid heuristic for the TSP
Baraglia R., Hidalgo Pèrez I., Perego R.
In this paper we investigate the design of a coarse-grained parallel implementation of Cga-LK, a hybrid heuristic for the Traveling Salesman Problem (TSP). Cga-LK exploits a compact genetic algorithm in order to generate high-quality tours which are then refined by means of an efficient implementation of the Lin-Kernighan local search heuristic. The results of several experiments conducted on a cluster of workstations with different TSP instances show the efficacy of the parallelism exploitation.Source: Applications of evolutionary computing : EvoWorkshops 2001: EvoCOP, EvoFlight, EvoIASP, EvoLearn, and EvoSTIM, pp. 193–202, Como, Italy, 18-20 April 2001
DOI: 10.1007/3-540-45365-2_20
Metrics:
Baraglia R., Hidalgo Pèrez I., Perego R.
In this paper we investigate the design of a coarse-grained parallel implementation of Cga-LK, a hybrid heuristic for the Traveling Salesman Problem (TSP). Cga-LK exploits a compact genetic algorithm in order to generate high-quality tours which are then refined by means of an efficient implementation of the Lin-Kernighan local search heuristic. The results of several experiments conducted on a cluster of workstations with different TSP instances show the efficacy of the parallelism exploitation.Source: Applications of evolutionary computing : EvoWorkshops 2001: EvoCOP, EvoFlight, EvoIASP, EvoLearn, and EvoSTIM, pp. 193–202, Como, Italy, 18-20 April 2001
DOI: 10.1007/3-540-45365-2_20
Metrics:
See at:
doi.org | CNR ExploRA
2002
Conference article
Unknown
SUGGEST: a Web usage mining system
Baraglia R., Palmerini P.
During their navigation web users leave many records of their activity. This huge amount of data can be a useful source of knowledge. Sophisticated mining processes are needed for this knowledge to be extracted, understood and used. In this paper we propose aWeb UsageMining (WUM) system, called SUGGEST , designed to efficiently integrate the WUM process with the ordinary web server functionalities. It can provide useful information to make easier the web user navigation and to optimize the web server performance. Two quantities are introduced in order to give a measure of the quality of our WUM system.Source: International Conference on Information Technology: Coding and Computing - ITCC 2002, pp. 282–287, Las Vegas, US, 8-10 April 2002
Baraglia R., Palmerini P.
During their navigation web users leave many records of their activity. This huge amount of data can be a useful source of knowledge. Sophisticated mining processes are needed for this knowledge to be extracted, understood and used. In this paper we propose aWeb UsageMining (WUM) system, called SUGGEST , designed to efficiently integrate the WUM process with the ordinary web server functionalities. It can provide useful information to make easier the web user navigation and to optimize the web server performance. Two quantities are introduced in order to give a measure of the quality of our WUM system.Source: International Conference on Information Technology: Coding and Computing - ITCC 2002, pp. 282–287, Las Vegas, US, 8-10 April 2002
See at: CNR ExploRA
2007
Conference article
Restricted
Local search for Grid scheduling
Klusacek D., Matyska L., Rudova H., Baraglia R., Capannini G.
This work introduces local search based algorithms as a new technique for the Grid scheduling problem. Specific algorithms based on dispatching rules and local search were proposed and implemented to generate schedule for dynamically arriving jobs. Algorithm performance was compared with typical queue-based algorithms from the point of view of objective function optimisation and time required to generate scheduling solutions. Grid environment was simulated by Alea Simulator which is based on modified and extended Grid- Sim toolkit. The results showed that local search based algorithms may be promising technique with better performance than queue-based approaches while still fast enough to provide solution in a reasonable time.Source: Doctoral Consortium at the International Conference on Automated Planning and Scheduling. ICAPS, Providence, Rhode Island, USA, September 22 - 26 2007
Klusacek D., Matyska L., Rudova H., Baraglia R., Capannini G.
This work introduces local search based algorithms as a new technique for the Grid scheduling problem. Specific algorithms based on dispatching rules and local search were proposed and implemented to generate schedule for dynamically arriving jobs. Algorithm performance was compared with typical queue-based algorithms from the point of view of objective function optimisation and time required to generate scheduling solutions. Grid environment was simulated by Alea Simulator which is based on modified and extended Grid- Sim toolkit. The results showed that local search based algorithms may be promising technique with better performance than queue-based approaches while still fast enough to provide solution in a reasonable time.Source: Doctoral Consortium at the International Conference on Automated Planning and Scheduling. ICAPS, Providence, Rhode Island, USA, September 22 - 26 2007
See at:
abotea.rsise.anu.edu.au | CNR ExploRA
2008
Conference article
Restricted
VoRaQue: RAnge QUeries on voronoi overlays
Albano M., Ricci L., Baldanzi M., Baraglia R.
This paper presents VoRaQue, a software layer supporting range queries on Voronoi P2P overlays. VoRaQue maps data in a 2-dimensional space. The P2P overlay is defined by links connecting nodes that are close in the 2-dimensional space and by a set of long-range links which guarantee a poly-logarithmic routing. When a query is submitted, VoRaQue finds out a node belonging to the region defined by the query. A multicast spanning tree covering that region is then built by applying compass routing, a distributed protocol to embed a spanning tree into a Delaunay Triangulation. The paper presents the basic VoRaQue protocol, then introduces a set of optimizations and finally presents some experimental results.Source: IEEE Symposium on Computers and Communications, pp. 495–500, Marrakech, Morocco, 6-9 Luglio 2008
DOI: 10.1109/iscc.2008.4625648
Metrics:
Albano M., Ricci L., Baldanzi M., Baraglia R.
This paper presents VoRaQue, a software layer supporting range queries on Voronoi P2P overlays. VoRaQue maps data in a 2-dimensional space. The P2P overlay is defined by links connecting nodes that are close in the 2-dimensional space and by a set of long-range links which guarantee a poly-logarithmic routing. When a query is submitted, VoRaQue finds out a node belonging to the region defined by the query. A multicast spanning tree covering that region is then built by applying compass routing, a distributed protocol to embed a spanning tree into a Delaunay Triangulation. The paper presents the basic VoRaQue protocol, then introduces a set of optimizations and finally presents some experimental results.Source: IEEE Symposium on Computers and Communications, pp. 495–500, Marrakech, Morocco, 6-9 Luglio 2008
DOI: 10.1109/iscc.2008.4625648
Metrics:
See at:
doi.org | ieeexplore.ieee.org | CNR ExploRA
2009
Conference article
Open Access
Efficient broadcast on area of interest in voronoi overlays
Mordacchini M., Albano M., Baraglia R., Ricci L.
This paper presents an algorithm to perform the broadcasting of a packet to all the peers that are located into a convex region (Area of Interest) in a Voronoi based peer-to-peer network. The proposed algorithm is an advanced version of the compass routing algorithm, and it is able to guarantee the delivery of 100% of the packets, while minimizing the total number of packets that travel the network. The algorithm has been theoretically analyzed, and it has been implemented on a proof of concept peer-to-peer application, and experimental results show that the algorithm actually respects the reduced number of total packets used, as per the theoretical analysis.Source: International Conference on Computational Science and Engineering, pp. 224–231, Vancouver, Canada, 29-31 Agosto 2009
DOI: 10.1109/cse.2009.293
Project(s): S-CUBE
Metrics:
Mordacchini M., Albano M., Baraglia R., Ricci L.
This paper presents an algorithm to perform the broadcasting of a packet to all the peers that are located into a convex region (Area of Interest) in a Voronoi based peer-to-peer network. The proposed algorithm is an advanced version of the compass routing algorithm, and it is able to guarantee the delivery of 100% of the packets, while minimizing the total number of packets that travel the network. The algorithm has been theoretically analyzed, and it has been implemented on a proof of concept peer-to-peer application, and experimental results show that the algorithm actually respects the reduced number of total packets used, as per the theoretical analysis.Source: International Conference on Computational Science and Engineering, pp. 224–231, Vancouver, Canada, 29-31 Agosto 2009
DOI: 10.1109/cse.2009.293
Project(s): S-CUBE
Metrics:
See at:
www.di.unipi.it | doi.org | ieeexplore.ieee.org | CNR ExploRA
2004
Contribution to conference
Open Access
An Effective Recommender System for Highly Dynamic and Large Web Sites
Baraglia R., Merlo F., Silvestri F.
In this demo we show a recommender system, called SUGGEST, that dynamically generates links to pages that have not yet been visited by a user and might be of his potential interest. Usually other recommender systems exploit a kind of two-phase architecture composed by an o -line component that analyzes Web server access logs and generates information used by a successive online component that generates recommendations. SUGGEST collapse the two-phase into a single online Apache module. The component is able to manage very large Web sites made up of dinamically generated pages by means of an e cient LRU-based database management strategy. The demo will show the way SUGGEST is able to anticipate users' requests that will be made farther in the future, introducing a limited overhead on the Web server activitySource: 15th European Conference on Machine Learning (ECML) and the 8th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD) (ECML/PHDD), Pisa, Italy, 20-24 September 2004
Baraglia R., Merlo F., Silvestri F.
In this demo we show a recommender system, called SUGGEST, that dynamically generates links to pages that have not yet been visited by a user and might be of his potential interest. Usually other recommender systems exploit a kind of two-phase architecture composed by an o -line component that analyzes Web server access logs and generates information used by a successive online component that generates recommendations. SUGGEST collapse the two-phase into a single online Apache module. The component is able to manage very large Web sites made up of dinamically generated pages by means of an e cient LRU-based database management strategy. The demo will show the way SUGGEST is able to anticipate users' requests that will be made farther in the future, introducing a limited overhead on the Web server activitySource: 15th European Conference on Machine Learning (ECML) and the 8th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD) (ECML/PHDD), Pisa, Italy, 20-24 September 2004
See at:
ISTI Repository | CNR ExploRA
2004
Contribution to conference
Open Access
Design of a OGSA-Compliant Grid Information Service Using .NET Technologies
Baraglia R., Laforenza D., Gaeta A., Ritrovato P., Gaeta M.
The Grid's new trend is represented by the migration towards a model built on concepts and technologies that are inherited from Grid and Web Services communities. From the merging of these two technologies, the new concept of Grid Service has merged and has been formalized with the introduction of the Open Grid Services Architecture (OGSA). OGSA defines the semantics of Grid Service instance, such as, how it is created, how it is named, how its lifetime is determined. OGSA does not place any requirements on implementation aspects. No mandatory constraint is requested for implementing Grid Services; the developers can explicit the features that characterize their target implementation environment. In the framework of the Grid Based Application Service Provision (GRASP) European project we are developing a OGSA compliant middleware by using .NET technologies. According to this goal we are investigate the design of a Grid Information Service (GIS) by exploiting these technologies, which we consider an interesting operating environment for Grid Services, due to high level integration of the services provided. Advantages and drawbacks of both these technologies and our solution are pointed out.Source: VECPAR' 04, pp. 1–13, Valencia, Spain, 28-30 June 2004
Baraglia R., Laforenza D., Gaeta A., Ritrovato P., Gaeta M.
The Grid's new trend is represented by the migration towards a model built on concepts and technologies that are inherited from Grid and Web Services communities. From the merging of these two technologies, the new concept of Grid Service has merged and has been formalized with the introduction of the Open Grid Services Architecture (OGSA). OGSA defines the semantics of Grid Service instance, such as, how it is created, how it is named, how its lifetime is determined. OGSA does not place any requirements on implementation aspects. No mandatory constraint is requested for implementing Grid Services; the developers can explicit the features that characterize their target implementation environment. In the framework of the Grid Based Application Service Provision (GRASP) European project we are developing a OGSA compliant middleware by using .NET technologies. According to this goal we are investigate the design of a Grid Information Service (GIS) by exploiting these technologies, which we consider an interesting operating environment for Grid Services, due to high level integration of the services provided. Advantages and drawbacks of both these technologies and our solution are pointed out.Source: VECPAR' 04, pp. 1–13, Valencia, Spain, 28-30 June 2004
See at:
ISTI Repository | CNR ExploRA
2003
Report
Open Access
A static mapping heuristic for mapping parallel applications to heterogeneous computing systems
Baraglia R., Ferrini R., Ritrovato P.
To minimize the execution time of a parallel application running on a heterogeneous computing distributed system, an appropriate mapping scheme to allocate the application tasks to the processors is needed. The general problem of mapping tasks to machines is a well known NP-hard problem and several heuristics have been proposed to approximate its optimal solution. In this paper we propose a static graph-based mapping algorithm, called Heterogeneous Multi-phase Mapping (HMM), that permits a suboptimal mapping of a parallel application onto a heterogeneous computing distributed system by using a local search technique together with a tabu search meta-heuristic. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application. We compare HMM with three different leading techniques and with an exhaustive mapping algorithm. We also give an example of mapping of a pratical application where HMM verified its usefulness. Experimental results show that HMM performs well demonstrating the applicability of our approach.Source: ISTI Technical reports, 2003
Baraglia R., Ferrini R., Ritrovato P.
To minimize the execution time of a parallel application running on a heterogeneous computing distributed system, an appropriate mapping scheme to allocate the application tasks to the processors is needed. The general problem of mapping tasks to machines is a well known NP-hard problem and several heuristics have been proposed to approximate its optimal solution. In this paper we propose a static graph-based mapping algorithm, called Heterogeneous Multi-phase Mapping (HMM), that permits a suboptimal mapping of a parallel application onto a heterogeneous computing distributed system by using a local search technique together with a tabu search meta-heuristic. HMM allocates parallel tasks by exploiting the information embedded in the parallelism forms used to implement an application. We compare HMM with three different leading techniques and with an exhaustive mapping algorithm. We also give an example of mapping of a pratical application where HMM verified its usefulness. Experimental results show that HMM performs well demonstrating the applicability of our approach.Source: ISTI Technical reports, 2003
See at:
ISTI Repository | CNR ExploRA
2001
Report
Unknown
Metapsi: a web-based metacomputing problem-solving environment for buiding complex applications
Baraglia R., Laforenza D.
The increasing complexity of large distributed scientific applications raises the problem of the coordination of diverse computational resources (computers, data bases, etc.). Multi-disciplinary applications often make use of coupled computational resources that cannot be replicated at a single site. There is the need for smart and user-friendly Problem-Solving Environments (PSE) that free scientists from concerns related to the location and complexity of the computing platform being used.Source: ISTI Technical reports, 2001
Baraglia R., Laforenza D.
The increasing complexity of large distributed scientific applications raises the problem of the coordination of diverse computational resources (computers, data bases, etc.). Multi-disciplinary applications often make use of coupled computational resources that cannot be replicated at a single site. There is the need for smart and user-friendly Problem-Solving Environments (PSE) that free scientists from concerns related to the location and complexity of the computing platform being used.Source: ISTI Technical reports, 2001
See at: CNR ExploRA