Electrical and Computer Eingineering

The resource-constrained project scheduling problem (RCPSP) is an extensively explored area. The existing RCPSP solutions tend to focus on single project scheduling problems without practical supports to address complex constraints, dynamic environments, and multi-project schedule coordination. This paper proposes a dynamic project scheduling algorithm based on partial task network heuristics. This algorithm takes time constraints, resource constraints, and particularly the changing task execution status into consideration. To coordinate conflicting schedules of multiple projects, we proposed an interactive decision support process and developed new algorithms for conflict detection, conflict resolution, and impact analysis. The proposed algorithms are fully implemented and tested in a web-based aircraft maintenance management system and are being applied in construction for project schedulingand facilities maintenance management.

To establish effective information exchange among applications in a distributed environment, participants not only share their functions and service interfaces, but often exchange data models. This paper proposes the use of ontologies to represent data models thus allowing applications to locate and integrate these models. A reference ontology based approach for service oriented ontology management is introduced. Specifically, a domain-specific reference ontology for use in the evaluation of a practical case is developed. To validate and evaluate the approach, a prototype system is developed to provide ontology deploying, browsing and mapping operations based on a service-oriented system. Experiments provide promising results that are consistent with the original ideas of managing ontologies and optimizing ontology mappings to facilitate data interoperability in a distributed environment.

business, government, health, education, culture and entertainment can take advantages of web technologies, such as functionality reuse, cost reduction and operational efficiency. Furthermore, web service technologies have also been widely adopted because of the availability of many standards, for instance the Web Services Description Language-WSDL (WSDL, 2007) and the Web Services Business Process Execution Language-WS-BPEL (ALVES et al., 2007). Web 2.0 technologies (O'REILLY, 2005), including social networks and wikis, have enhanced the interactivity and user-generated content found on the original web (BERNERS-LEE, 1999), promoting the development of new types of applications and facilitating the way users interact with computers. The Semantic Web (BERNERS-LEE et al., 2001) allows the Internet to be used by computer programs as well as by humans, relying on knowledge formalizations known as ontologies (GRUBER, 2007). It can be viewed as a conceptual model that has logic formalizations rigorously describing the world. This model allows the web to be used not just as a set of documents that are interrelated through hyperlinks, but also as a semantic network of concepts. In the health domain, the low process predictability and the loose coupling of organizational units, support the argument of the collaborative platform potential in organizations.

This paper presents results from a quantitative research that was conducted among 260 participants of a software quality event in Brazil. This research aims the understanding the occurrence of several IT problems in the analyzed organizations and the impact of the quality instruments adoption on those problems. The main contribution is the identification of the respondent's perception about the relationship of the quality instruments adoption and their impact on several IT problems throughout statistical analysis of the data.

WSBPEL (Web Services for Business Process Execution Language) is a process modelling language for composing Web Services. Abstract processes can be used in WSBPEL as process templates, which describe abstract activities without specifying the execution details and the service bindings. However, it is a challenge to refine an abstract process into a concrete executable process for the purpose of adapting to different business requirements. In order to discover the potential business partners and Web Services, we propose a profile-based service matching and discovery approach for semi-automatic semantic process representation that occurs during design time. Specifically, our approach utilizes semantic profiles to specify the semantic descriptions of process activities. Consequently, our methodology provides substantial flexibility for abstract process composition while reusing existing processes and services.

Service evolution is the process of maintaining and evolving existing Web services to cater for new requirements and technological changes. In this paper, a service evolution model is proposed to analyze service dependencies, identify changes on services and estimate impact on consumers that will use new versions of these services. Based on the proposed service evolution model, four service evolution patterns are described: compatibility, transition, split-map, and mergemap. These proposed patterns provide reusable templates to encourage well-defined service evolution while minimizing issues that arise otherwise. They can be applied in the service evolution scenario where a single service is used by many, possibly unknown, consumers' applications. In such a scenario, providers evolve their services independently from consumers, which might cause unexpected errors and incur unpredicted impact on the dependent consumers' applications. Therefore, providers can use these patterns to estimate the impact that changes to be introduced to their services may cause on their consumers, and to allow consumers smoothly migrate to the newest version of the service.

The resource-constrained project scheduling problem (RCPSP) is an extensively explored area. The existing RCPSP approaches tend to focus on single project scheduling problems without practical support to address the multiple project schedule coordination which involves constraints defined across projects. This paper extends RCPSP by involving time and resource constraints and proposes a practical dynamic task network scheduling algorithm. This algorithm takes time constraints, resource constraints, and particularly the dynamic task execution status into consideration. Dynamic scheduling through a partial task network is considered a unique feature of this algorithm. The proposed algorithm is fully implemented and tested in a web-based aircraft inspection maintenance management system. I.

Software developers require information to understand the characteristics of systems, such as complexity and maintainability. In order to further understand and determine characteristics of object-oriented (OO) systems, this paper describes research that identifies attributes that are valuable in determining the difficulty in implementing changes during maintenance, as well as the possible effects that such changes may produce. A set of metrics are proposed to quantify and measure these attributes. The proposed complexity metrics are used to determine the difficulty in implementing changes through the measurement of method complexity, method diversity, and complexity density. The paper establishes impact metrics to determine the potential effects of making changes to a class and dependence metrics that are used to measure the potential effects on a given class resulting from changes in other classes. The case study shows that the proposed metrics provide additional information not s...

The frequent transfers' challenge of workpieces between multiple resources is quite evident in the production process of customized parts. In fact, special jobs' transfers and processing, often, require workpiece unloading, transport and loading with, rather, idling and reconfiguration of resources that impact much job completion time and resource utilization. The overlapping capabilities of machine tools, otherwise, are common with, typically, few special tooling. In such settings, the overlapping and special tooling capabilities intensify the complexity of the assignment problem, mainly, when allocating the operations of arbitrary processing times. This work targets the efficient assignment of unrelated jobs of operations with arbitrary processing time to multiple resources of partially overlapping capabilities. The work introduces a formal model and a more efficient solution approach for minimizing jobs' transfer and balancing workloads. The sequencing problem of the assigned unrelated jobs would be, then, an orthogonal problem, of less significance, that can be tackled separately. *