32680139
Multi-user Object-Oriented Environments
Network-based computer environments emulating selected aspects of the physical world and allowing interaction among their human users first appeared in the late 1970s. These environments implemented a networked version of a role-playing fantasy game known as Dungeons and Dragons, hence their acronym MUD (Multi-user Dungeons). When it became obvious that many MUD users use the environment mainly to meet virtually with other users rather than to play games, new forms of MUDs and other types of emulated universes were developed and the term Virtual Environment (VE) was introduced to refer to all of them.
35073381
Service Logic Deployment and Distribution Configuration
The success of service providers in the competitive communications market of the future will be determined by the efficiency with which services are developed, and the quality levels at which services are provided. A service creation environment (SCE) should provide the service developer with solutions to these problems. In this paper we present two essential facilities that should be provided by an advanced SCE: a tool for the optimisation of the service logic deployment scheme and a distribution configuration language supporting the deployment and configuration of component-based distributed applications.
203567
Separating replication from distributed communication: problems and solutions
Replication and distributed communication are usually tightly coupled. This code tangling forbids their independent reuse and adaptation. In this position paper, the problems resulting from coupling replication with distributed communication are discussed. In addition, a solution based on separation of concerns is proposed. The abstractions for each concern are presented, as well as their composition.
38014527
A Quality Design Solution for Object Synchronization
This paper presents a quality design solution, the Customizable Object Synchronization pattern, for object synchronization which decouples object synchronization from object concurrency and object functionality (sequential part). The solution described by this pattern provides encapsulation, extensibility, modularity and reuse of synchronization policies.
11562802
A Decision Support System for IST Academic Information
This article describes the Decision Support System (DSS) for Academic Information being developed at Instituto Superior Tecnico, the Engineering School of the Technical University of Lisbon. In Portuguese, this project has been given the acronym SADIA (Sistema de Apoio a Decisao da Informacao Academica). This paper focuses on the early phases of the DSS development process, i.e., the business requirements definition and the dimensional modelling. First, we show how the business requirements of the School drive the definition of the DSS dimensional model. Second, we detail the logical dimensional model for a selected business process, the IST Student Admission process. Third, the corresponding physical design decisions are reported. The results obtained from the three phases were successfully validated by business users.
16566221
Naming: design pattern and framework
Naming is an important, but frequently overlooked, aspect of software systems. Naming is usually combined with other issues, e.g. distributed communication technology. The paper treats naming in isolation. It presents a naming design pattern which abstracts several naming policies and an object-oriented framework that can be customized to support naming policies. An applications designer can choose the correct naming properties (relative, absolute, universal identifiers, etc.) to refer to specific objects.
1002750
Particle Swarm based Data Mining Algorithms for classification tasks
Particle Swarm Optimisers are inherently distributed algorithms where the solution for a problem emerges from the interactions between many simple individual agents called particles. This article proposes the use of the Particle Swarm Optimiser as a new tool for Data Mining. In the first phase of our research, three different Particle Swarm Data Mining Algorithms were implemented and tested against a Genetic Algorithm and a Tree Induction Algorithm (J48). From the obtained results, Particle Swarm Optimisers proved to be a suitable candidate for classification tasks. The second phase was dedicated to improving one of the Particle Swarm optimiser variants in terms of attribute type support and temporal complexity. The data sources here used for experimental testing are commonly used and considered as a de facto standard for rule discovery algorithms reliability ranking. The results obtained in these domains seem to indicate that Particle Swarm Data Mining Algorithms are competitive, not only with other evolutionary techniques, but also with industry standard algorithms such as the J48 algorithm, and can be successfully applied to more demanding problem domains.
38034228
On the Power of P Systems with DNA-Worm-Objects
We introduce a variant of P systems with string-objects - called worm-objects - inspired in the DNA computing area. These systems work with multisets of string-objects processed by splitting, mutation, replication and recombination. This model is simpler (we eliminate the replication operation) and more realistic (the recombination operation is changed by the simpler one of suffix-prefix or head-tail concatenation developed in the DNA computing framework) than the previous one. The result of a computation is the set of strings sent out of the system. We work with multisets of strings but we generate languages instead of sets of numbers. We prove that, without priority among rules or other control mechanisms, (1) these P systems with at most three membranes can generate all recursively enumerable languages, (2) with non-decreasing length mutation and splitting rules, three membranes are enough to generate the family of context-sensitive languages, and (3) with these restricted types of splitting and mutation rules, four membranes can generate the family of recursively enumerable languages.
7316091
SAM Method as an Approach to Select Candidates for Human Prostate Cancer Markers
In order to select gene markers among differentially expressed transcripts identified from tumoral prostate, we have applied a filter and Significance Analysis of Microarrays (SAM) as the feature selection method on a previously normalized dataset of DNA microarray experiments reported by Reis et al., 2004 (Oncogene 23:6684-6692). Twenty seven samples with different degrees of tumor differentiation (Gleason scores) were analyzed. SAM was run using either two-class, unpaired data analysis with Gleason 5-6 and Gleason 9-10 samples, or multiclass response analysis with an additional category of Gleason 7-8. Both strategies revealed a promising set of transcripts associated with the degree of differentiation of prostate tumors.
15673525
Genetic Algorithms for Component Analysis
Adapted waveform analysis is used extensively in audio, speech, and video coding. In this context, the basic problem is to find out the best representation for a given signal. The strategy is to decompose the signal into time-frequency atoms. The main analysis tool is the expansion of the signal in or-thonormal bases whose elements have good time-frequency localizations. We show that genetic algorithms can be exploited to search libraries of bases for atomic pattern recognition in noisy signals. The proposed algorithm generates best basis decomposition trees through the evolution of well-adapted genetic sequences. Two new types of constraint operators are introduced to guarantee that valid genetic sequences are generated. The approach behaves as an atomic analyzer for signal processing. A test environment is proposed to assess recognition of time-frequency atoms in signal spaces.
10782860
OrgSwarm - A Particle Swarm Model of Organizational Adaptation
This study extends the particle swarm metaphor to include the domain of organizational adaptation. A simulation model, OrgSwarm, is constructed in order to examine the impact of strategic inertia on the adaptive potential of a population of organizations. The key finding is that a degree of strategic inertia, in the presence of an election mechanism, can assist rather than hamper adaption of the population.