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.
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.
11594682
Framework, Design Patterns and Pattern Language for Object Concurrency
The development of concurrent applications is hard due to the diverse concerns involved and the non-determinism inherent to the implementation environment. In order to control such complexity developers can benefit from objectoriented frameworks providing application-independent solutions which can be specialized for the application-specific needs. A primary contribution of this paper is to describe a family of design patterns for object concurrency which are composed in a three-layered framework. In addition, a pattern language describing an incremental development process which is based on the framework and design patterns is also presented.
14281129
An abstraction for awareness management in collaborative virtual environments
This paper describes an object-oriented abstraction for the problem of awareness management in Collaborative Virtual Environments (CVEs). The described abstraction allows for different types of awareness information and awareness management policies to be used. It is also described how the defined abstraction was used to support the awareness management policies of two demo CVEs application.
8072493
Authorization and Access Control in Adaptive Workflows
In recent years we have witnessed the development of adaptive workflow management systems. These systems offer an extended set of features to support both ad-hoc and evolutionary changes, while ensuring correctness of process definition and their running instances. Ad-hoc and evolutionary changes impose new access control requirements, which have been neglected by adaptive workflow research and are not met by existing models for traditional workflow management systems (WfMSs). In this paper, we extend the role-based access control model for adaptive workflows. This extension is done by defining authorizations for adaptive WfMSs and adaptive authorizations.
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.
15079292
Measuring similarity between collection of values
In this paper, we propose a set of similarity metrics for manipulating collections of values occuring in XML documents.
 Following the data model presented in TAX algebra, we treat an XML element as a labeled ordered rooted tree. Consider that XML nodes can be either atomic, i.e, they may contain single values such as short character strings, date, etc, or complex, i.e., nested structures that contain other nodes, we propose two types of similarity metrics: MAVs, for atomic nodes and MCVs, for complex nodes. In the first case, we suggest the use of several application domain dependent metrics. In the second case, we define metrics for complex values that are structure dependent, and can be distinctly applied for it and collections of values. We also present experiments showing the effectiveness of our method.
5929323
Agent-based modelling of product invention
This study describes a novel simulation model of the process of product invention. Invention is conceptualized as a process of directed evolutionary adaptation, on a landscape of product design possibilities, by a population of profit-seeking agents (inventors). The simulation experiments examine the sensitivity of the rate of advance in product fitness to the choice of search heuristics employed by inventors. The key finding of the experiments is that if search heuristics are confined to those which are rooted in past experience, or to heuristics which merely generate variety, limited product advance occurs. Notable product fitness advance only occurs when inventor's expectations as to the relative fitness of potential product inventions are incorporated into the model of invention. The results demonstrate the importance of human direction and expectations in invention. They also support the importance of formal product / project evaluation procedures in organizations, and the importance of market information when inventing new products.
14702137
A Multi-Neighbor-Joining Approach for Phylogenetic Tree Reconstruction and Visualization
The computationally challenging problem of reconstructing the phylogeny of a set of contemporary data, such as DNA sequences or morphological attributes, was treated by an extended version of the neighbor-joining (NJ) algorithm. The original NJ algorithm provides a single-tree topology, after a cascade of greedy pairing decisions that tries to simultaneously optimize the minimum evolution and the least squares criteria. Given that some sub-trees are more stable than others, and that the minimum evolution tree may not be achieved by the original NJ algorithm, we propose a multi-neighbor-joining (MNJ) algorithm capable of performing multiple pairing decisions at each level of the tree reconstruction, keeping various partial solutions along the recursive execution of the NJ algorithm. The main advantages of the new reconstruction procedure are: 1) as is the case for the original NJ algorithm, the MNJ algorithm is still a low-cost reconstruction method; 2) a further investigation of the alternative topologies may reveal stable and unstable sub-trees; 3) the chance of achieving the minimum evolution tree is greater; 4) tree topologies with very similar performances will be simultaneously presented at the output. When there are multiple unrooted tree topologies to be compared, a visualization tool is also proposed, using a radial layout to uniformly distribute the branches with the help of well-known metaheuristics used in computer science.
30725726
An integrated MOLP method base package - A guided tour of tommix
Abstract An implementation of a MOLP interactive method base is presented in the form of a guided tour to a computer package. The MOLP method base (associated to a procedure toolbox) is a component of a decision support system framework which also integrates a dialogue base and a data management module. Besides providing the standard working of each method the interactive MOLP method base offers the possibility of method switching at any interaction with the decision maker (DM), in order to make the most of the potentialities of each method and support a “learning” process. Some key issues in the development of interactive MOLP approaches and computational tools are also discussed. Special attention is paid to the development of an user-friendly environment for interacting with the DM.
18811835
An Empirical Comparison of Particle Swarm and Predator Prey Optimisation
In this paper we present and discuss the results of experimentally comparing the performance of several variants of the standard swarm particle optimiser and a new approach to swarm based optimisation. The new algorithm, which we call predator prey optimiser, combines the ideas of particle swarm optimisation with a predator prey inspired strategy, which is used to maintain diversity in the swarm and preventing premature convergence to local suboptima. This algorithm and the most common variants of the particle swarm optimisers are tested in a set of multimodal functions commonly used as benchmark optimisation problems in evolutionary computation.