Volumen 10 | Número 01http://sedici.unlp.edu.ar:80/handle/10915/3962024-03-19T12:25:23Z2024-03-19T12:25:23ZDesign and implementation considerations for a pedagogical object oriented operating system: MTech Thesis, Jan 2009Chakraborty, Pinakihttp://sedici.unlp.edu.ar:80/handle/10915/96672019-06-22T20:02:34Z2010-04-01T00:00:00ZRevision
Journal of Computer Science & Technology; vol. 10, no. 1
For centuries, experimentation has been at the center of all successful scientific studies. Experimental explorations can offer new perceptions, weed out unproductive approaches and validate theories and practices. Computer Science (CS), as a discipline, has a poor record when it comes to experimental validation. The ratio of theoretical research claims that have not been experimentally verified is notably high in CS. The situation is no different in the field of system software where experimental research has now become a necessity. The thesis in discussion presents an experimental study on operating systems. The thesis first develops a design of a new operating system, called JNUOS, imparting several noble ideas and then provides a commentary on its implementation.
2010-04-01T00:00:00ZFor centuries, experimentation has been at the center of all successful scientific studies. Experimental explorations can offer new perceptions, weed out unproductive approaches and validate theories and practices. Computer Science (CS), as a discipline, has a poor record when it comes to experimental validation. The ratio of theoretical research claims that have not been experimentally verified is notably high in CS. The situation is no different in the field of system software where experimental research has now become a necessity. The thesis in discussion presents an experimental study on operating systems. The thesis first develops a design of a new operating system, called JNUOS, imparting several noble ideas and then provides a commentary on its implementation.<i>Algorithms of the Intelligent Web</i>: Haralambos Marmanis and Dmitry Babenko Manning Publications Co., 2009Maguitman, Ana Gabrielahttp://sedici.unlp.edu.ar:80/handle/10915/96662019-06-22T20:02:32Z2010-04-01T00:00:00ZRevision
Journal of Computer Science & Technology; vol. 10, no. 1
<i>Algorithms of the Intelligent Web</i> is a timely and instructive book that brings together techniques for the rapidly evolving field of intelligent web applications. It covers problems such as crawling, indexing, searching, integrating search results with link analysis and user’s clicks, generating recommendations, clustering and classification. The reader will become familiar with a large number of datasets, open-source libraries and APIs for developing intelligent web-based applications. The example-driven approach used by the authors puts the reader on a fast track to understanding the major techniques used in current applications. The emphasis is on practice rather than theory. Most of the techniques are presented in the form of algorithms without placing heavy emphasis on their mathematical aspects.
2010-04-01T00:00:00Z<i>Algorithms of the Intelligent Web</i> is a timely and instructive book that brings together techniques for the rapidly evolving field of intelligent web applications. It covers problems such as crawling, indexing, searching, integrating search results with link analysis and user’s clicks, generating recommendations, clustering and classification. The reader will become familiar with a large number of datasets, open-source libraries and APIs for developing intelligent web-based applications. The example-driven approach used by the authors puts the reader on a fast track to understanding the major techniques used in current applications. The emphasis is on practice rather than theory. Most of the techniques are presented in the form of algorithms without placing heavy emphasis on their mathematical aspects.Subquery allocations in distributed databases using genetic algorithmsGorla, NarasimhaiahSong, Suk-Kyuhttp://sedici.unlp.edu.ar:80/handle/10915/96652019-06-22T20:02:30Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
Minimization of query execution time is an important performance objective in distributed databases design. While total time is to be minimized for On Line Transaction Processing (OLTP) type queries, response time has to be minimized in Decision Support type queries. Thus different allocations of subqueries to sites and their execution plans are optimal based on the query type.
We formulate the subquery allocation problem and provide analytical cost models for these two objective functions. Since the problem is NP-hard, we solve the problem using genetic algorithm (GA).
Our results indicate query execution plans with total minimization objective are inefficient for response time objective and vice versa. The GA procedure is tested with simulation experiments using complex queries of up to 20 joins. Comparison of results with exhaustive enumeration indicates that GA produced optimal solutions in all cases in much less time.
2010-04-01T00:00:00ZMinimization of query execution time is an important performance objective in distributed databases design. While total time is to be minimized for On Line Transaction Processing (OLTP) type queries, response time has to be minimized in Decision Support type queries. Thus different allocations of subqueries to sites and their execution plans are optimal based on the query type.
We formulate the subquery allocation problem and provide analytical cost models for these two objective functions. Since the problem is NP-hard, we solve the problem using genetic algorithm (GA).
Our results indicate query execution plans with total minimization objective are inefficient for response time objective and vice versa. The GA procedure is tested with simulation experiments using complex queries of up to 20 joins. Comparison of results with exhaustive enumeration indicates that GA produced optimal solutions in all cases in much less time.Tools selection criteria in software-developing Small and Medium EnterprisesRivas, LornelPérez, MaríaMendoza, Luis E.Grimán P., Anna C.http://sedici.unlp.edu.ar:80/handle/10915/96642019-06-22T04:03:53Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
Nowadays,it's well-known that Small and Medium Enterprises (SMEs) generate important contributions to the software industry. Their particular characteristics constitute a challenge to decision makers when selecting technologies, like Software Engineering Tools (SETs). Deciding in which SET to invest requires managing limited resources as well as productivity pressures. Additionally, changes in SETs also affect the selection process. This article proposes a set of criteria, which were formulated with support on the Goal Question Metric approach and considered standards like ISO/IEC 14102 and IEEE 1209, to support SMEs in the selection of SETs. These criteria were also applied to three SETs, including both commercial and open-source, to obtain a set of opportunities for supporting software engineering areas, such as project management and software development process. This proposal is aimed at forming the basis to establish a SETs selection model for SMEs.
2010-04-01T00:00:00ZNowadays,it's well-known that Small and Medium Enterprises (SMEs) generate important contributions to the software industry. Their particular characteristics constitute a challenge to decision makers when selecting technologies, like Software Engineering Tools (SETs). Deciding in which SET to invest requires managing limited resources as well as productivity pressures. Additionally, changes in SETs also affect the selection process. This article proposes a set of criteria, which were formulated with support on the Goal Question Metric approach and considered standards like ISO/IEC 14102 and IEEE 1209, to support SMEs in the selection of SETs. These criteria were also applied to three SETs, including both commercial and open-source, to obtain a set of opportunities for supporting software engineering areas, such as project management and software development process. This proposal is aimed at forming the basis to establish a SETs selection model for SMEs.Using combination of actions in reinforcement learningKaranik, Marcelo J.Gramajo, Sergio D.http://sedici.unlp.edu.ar:80/handle/10915/96632019-06-22T04:03:51Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
Software agents are programs that can observe their environment and act in an attempt to reach their design goals. In most cases the selection of particular agent architecture determines the behaviour in response to the different problem states However, there are some problem domains in which it is desirable that the agent learns a good action execution policy by interacting with its environment. This kind of learning is called Reinforcement Learning and it is useful in the process control area. Given a problem state, the agent selects the adequate action to do and receives an immediate reward, then estimations about every action are updated and, after a certain period of time, the agent learns which the best action to be executed is. Most reinforcement learning algorithms perform simple actions while two or more are capable of being used. This work involves the use of RL algorithms to find an optimal policy in a gridworld problem and proposes a mechanism to combine actions of different types.
2010-04-01T00:00:00ZSoftware agents are programs that can observe their environment and act in an attempt to reach their design goals. In most cases the selection of particular agent architecture determines the behaviour in response to the different problem states However, there are some problem domains in which it is desirable that the agent learns a good action execution policy by interacting with its environment. This kind of learning is called Reinforcement Learning and it is useful in the process control area. Given a problem state, the agent selects the adequate action to do and receives an immediate reward, then estimations about every action are updated and, after a certain period of time, the agent learns which the best action to be executed is. Most reinforcement learning algorithms perform simple actions while two or more are capable of being used. This work involves the use of RL algorithms to find an optimal policy in a gridworld problem and proposes a mechanism to combine actions of different types.Semantics-based color assignment in visualizationLarrea, Martín LeonardoMartig, Sergio R.Castro, Silvia Mabelhttp://sedici.unlp.edu.ar:80/handle/10915/96622019-06-22T04:03:48Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
The active use and manipulation of visual representations makes many complex and intensive cognitive tasks feasible. A visual representation is able to convey relationships among many elements in parallel and it provides an individual with directly observable memory.
A successful visualization allows the user to gain insight into the data, that is, to communicate different aspects of the data in an effective way. Even with today's visualization systems that give the user a considerable control over the visualization process, it can be difficult to produce an effective visualization. To obtain useful results, a user has to interrogate the visualization very precisely. A strategy to improve this situation is to guide the user with the selection of the parameters involved in the visualization. This paper presents the initial effort dedicated to achieve a visualization system that assists the user in the configuration and preparation of the visualization by considering both the semantic of the data and the semantic of the stages through all the visualization process. In this article we present a visualization system for file hierarchies where color assignment is made by a reasoning process through the use of an ontology. This work sets the way forward to integrate the visualization process with a reasoning process and configure a visualization based on the reasoner s results.
2010-04-01T00:00:00ZThe active use and manipulation of visual representations makes many complex and intensive cognitive tasks feasible. A visual representation is able to convey relationships among many elements in parallel and it provides an individual with directly observable memory.
A successful visualization allows the user to gain insight into the data, that is, to communicate different aspects of the data in an effective way. Even with today's visualization systems that give the user a considerable control over the visualization process, it can be difficult to produce an effective visualization. To obtain useful results, a user has to interrogate the visualization very precisely. A strategy to improve this situation is to guide the user with the selection of the parameters involved in the visualization. This paper presents the initial effort dedicated to achieve a visualization system that assists the user in the configuration and preparation of the visualization by considering both the semantic of the data and the semantic of the stages through all the visualization process. In this article we present a visualization system for file hierarchies where color assignment is made by a reasoning process through the use of an ontology. This work sets the way forward to integrate the visualization process with a reasoning process and configure a visualization based on the reasoner s results.A Broadcast Disk scheme for mobile information systemSumari, PutraMat Darus, RozaidaRahiman, Amir Rizaanhttp://sedici.unlp.edu.ar:80/handle/10915/96612019-06-22T04:03:48Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
The rapidly expanding technology of cellular communications, wireless local area network (LAN), wireless data networks and satellite gives mobile users the ability of accessing information anywhere and anytime. Data broadcasting algorithm plays an important role as it instructs the server to disseminate large amount of data at a fast rate to many mobile clients. One of the work known as the Broadcast Disk method creates a sequence of slots containing data and broadcasts them in a circular manner on the air. Mobile clients keep listening to the air and catch those slots that interest them. However in the Broadcast Disk method, some slots are empty, which results to waste of resources and increase in clients' average waiting time. Empty slots are randomly generated and difficult to be located. In this paper we present a scheme called the Optimum Broadcast Disk, which is an enhancement of the Broadcast Disk method to overcome the empty slots issue and hence reduce the users' waiting time. We manage to locate these empty slots and fill them with popular data. We demonstrate by case studies and simulation that our scheme eliminates empty slots and minimizes clients' average waiting time.
2010-04-01T00:00:00ZThe rapidly expanding technology of cellular communications, wireless local area network (LAN), wireless data networks and satellite gives mobile users the ability of accessing information anywhere and anytime. Data broadcasting algorithm plays an important role as it instructs the server to disseminate large amount of data at a fast rate to many mobile clients. One of the work known as the Broadcast Disk method creates a sequence of slots containing data and broadcasts them in a circular manner on the air. Mobile clients keep listening to the air and catch those slots that interest them. However in the Broadcast Disk method, some slots are empty, which results to waste of resources and increase in clients' average waiting time. Empty slots are randomly generated and difficult to be located. In this paper we present a scheme called the Optimum Broadcast Disk, which is an enhancement of the Broadcast Disk method to overcome the empty slots issue and hence reduce the users' waiting time. We manage to locate these empty slots and fill them with popular data. We demonstrate by case studies and simulation that our scheme eliminates empty slots and minimizes clients' average waiting time.A new AntTree-based algorithm for clustering short-text corporaErrecalde, Marcelo LuisIngaramo, Diego AlejandroRosso, Paolohttp://sedici.unlp.edu.ar:80/handle/10915/96602019-06-22T04:03:46Z2010-04-01T00:00:00ZArticulo
Journal of Computer Science & Technology; vol. 10, no. 1
Research work on "short-text clustering" is a very important research area due to the current tendency for people to use "small-language", e.g. blogs, textmessaging and others. In some recent works, new bioinspired clustering algorithms have been proposed to deal with this difficult problem and novel uses of Internal Clustering Validity Measures have also been presented. In this work, a new AntTree-based approach is proposed for this task. It integrates information on the Silhouette Coefficient and the concept of attraction of a cluster in different stages of the clustering process. The proposal achieves results comparable to the best reported results in this area, showing an interesting stability in the quality of the results and presenting some interesting capabilities as a general improvement method for arbitrary clustering approaches.
2010-04-01T00:00:00ZResearch work on "short-text clustering" is a very important research area due to the current tendency for people to use "small-language", e.g. blogs, textmessaging and others. In some recent works, new bioinspired clustering algorithms have been proposed to deal with this difficult problem and novel uses of Internal Clustering Validity Measures have also been presented. In this work, a new AntTree-based approach is proposed for this task. It integrates information on the Silhouette Coefficient and the concept of attraction of a cluster in different stages of the clustering process. The proposal achieves results comparable to the best reported results in this area, showing an interesting stability in the quality of the results and presenting some interesting capabilities as a general improvement method for arbitrary clustering approaches.