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.
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.
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.
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.
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.
8086424
Dynamic evolution in workflow management systems
The environments where workflow management systems are typically used in are constantly changing. It is nearly impossible to foresee, at business process design stage, all the combinations of tasks needed to achieve the process' goals. Workflow management systems capable of supporting dynamic changes on executing instances in a flexible manner are thereby demanded. Former approaches have proposed a solution to this issue based on workflow type versioning and workflow instance migration. However, the operations that handle the modification of workflow types as well as the migration algorithm for workflow instances are tied to a particular representation of workflow types. This means that whenever the representation changes, the migration algorithms and the modification operations have to change accordingly. This is a current problem due to the uprising of different specifications for workflow definition languages, which are far away from stabilizing. In this paper, we address this problem by clearly decoupling the modification operations of workflow types from the internal structures and algorithms responsible for the instances' migration. In this manner we enable the use of different workflow definition languages while keeping the same internal structures and migration algorithms.
8450178
Information Retrieval Aware Web Site Modelling and Generation
Design and maintenance of large corporate Web sites have become a challenging problem due to the continuing increase in their size and complexity. One particular feature present in the majority of this sort of Web sites is searching for information. However the solutions provided so far, which is based on the same techniques used for search in the open Web, have not provided a satisfactory performance to specific Web sites, often resulting in too much irrelevant content in a query answer. This paper proposes an approach to Web site modelling and generation of intrasite search engines, combining application modelling and information retrieval techniques. Our assumption is that giving search engines access to the information provided by conceptual representations of the Web site improves their performance and accuracy. We demonstrate our proposal by describing a Web site modelling language that represent both traditional modelling features and information retrieval aspects, as well as presenting experiments to evaluate the resulting intrasite search engine generated by our method.
19002308
Planning Brazilian Urban Traffic with a Geographic Application Software
Planning and optimizing urban traff ic is a diff icult problem, with considerable economic and social impacts. The development of suitable software tools to aid municipal governments to control and to improve the traff ic flow is urgent due to the increasing number of vehicles in urban areas. However, the development of this kind of software represents a great challenge since the problems to be dealt with in this domain are both computationally and mathematically complex. This article presents a geographic application software as a feasible solution for this problem. The solution is geared towards Brazilian medium to large cities and is based on a mathematical model of the urban traff ic. This model is stored in a geographic database and allows the user of the software (typicall y a traff ic engineer) to search for alternative solutions for traff ic problems. The software can provide optimal solutions for an important family of traff ic problems, namely the Traff ic Equili brium Problem (TEP). This family involves the common hashing problems (e.g. traff ic bottlenecks) as well as more sophisticated problems li ke vehicles’ pollution minimization. We have developed a prototype of the software and its solutions for the TEP were empiricall y validated against real traff ic data from Goiânia, capital of the Brazilian state of Goiás.
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.
12874902
Behavioural Differential Equations and Coinduction for Binary Trees
We study the set TA of infinite binary trees with nodes labelled in a semiring A from a coalgebraic perspective. We present coinductive definition and proof principles based on the fact that TA carries a final coalgebra structure. By viewing trees as formal power series, we develop a calculus where definitions are presented as behavioural differential equations. We present a general format for these equations that guarantees the existence and uniqueness of solutions. Although technically not very difficult, the resulting framework has surprisingly nice applications, which is illustrated by various concrete examples.
32839673
Genomics and Gene Expression Management Tools for the Schistosoma Mansoni cDNA Microarray Project
IV BSB 22 Favor ver os Anais do Simpósio em Springer Verlag, Lecture Notes in Bioinformatics (LNBI número 3594) para este trabalho.