Formal requirements modeling with executable use cases and Coloured Petri Nets

This paper presents executable use cases (EUCs), which constitute a model-based approach to requirements engineering. EUCs may be used as a supplement to model-driven development (MDD) and can describe and link user-level requirements and more technical software specifications. In MDD, user-level requirements are not always explicitly described, since usually it is sufficient that one provides a specification, or platform-independent model, of the software that is to be developed. Therefore, a combination of EUCs and MDD may have potential to cover the path from user-level requirements via specifications to implementations of computer-based systems

A requirements engineering and management training course for software development professionals

Devising a course for software professionals working in industry depends on several factors. In order to create a course that fulfils professionals’ expectations, it is important to take account of the skills of the participants, the time available, and the specific topics to be covered. This paper presents the curriculum of a course in requirements engineering and management intended for software developers with a first-level academic degree in computing and experience in developing real software solutions. This context requires the course to concentrate on topics that were not taught in the participants’ previous education and that can have a positive impact on their daily practices

Ultrasound velocity profile (UVP) measurements in shallow open-channel flows

1st European IAHR Congress, 6-4 May, Edinburgh, ScotlandThis paper is concerned with velocity measurements in shallow water flows by using Ultrasonic Velocity Profile (UVP)probes. The measurements were made in a 10 m long, 0.4 m wide flume whose slope is 0.00117. Diagonal and horizontal positioning of a single probe and the combination of two probes were tested as configurations of the UVP probes. Streamwise and transverse velocities were obtained. A sensitivity analysis was performed to UVP parameters, namely to the distance of the window for each measurement and to the distance between each measuring point. The influence of four different seeding materials was also assessed. Filters for eliminating noise and spikes were applied. For 1D measurements, UVP streamwise velocities were compared with Pitot tube measurements. For 2D measurements, streamwise velocities and turbulent intensities were compared with known laws. The results show the importance of i) setting optimal UVP parameters values, ii) of positioning adequately the UVP probes and iii) using appropriate seeding

Simple camera calibration for light measurements

The availability and decreasing prices of digital photographic cameras using megapixel sensors could point to its use as high quality light measuring devices if simple and effective calibration procedures could be put to work.This paper proposes such a system, using a common digital camera combined with low cost reference color charts. The procedure to obtain the response function of the camera, the production of the color chart and its calibration is presented.In this way, it is possible to obtain light measurements otherwise only possible with sophisticated and expensive equipments.The research work is being conducted with partial funding from FCT (Portuguese Foundation for Science and Technology)

Calibration of camera for light quality measurements of low-power lamps

Environmental concerns and power efficiency point to increased use of power efficient lamps. Different manufacturers and price targets produce a wide range of light outputs, varying in intensity and spectral distribution. This type of apparatus also presents a non-linear load to the electric power supply, introducing some problems that should be taken in consideration and corrected as much as possible. To be able to measure light quality, we propose a technique that uses a conventional digital photographic camera and a set of colour-reference reflective cards. By analysis of the obtained images, a colour quality index can be computed and used to compare different type of lamps. The calibration of the set-up is crucial for the approach and some problems need to be solved for the reliability of the method.This work is being conducted at Algoritmi Research Centre, University of Minho and sponsored by FCT- Fundação para a Ciência e Tecnologia, Portugal

Designing tool support for translating use cases and UML 2.0 Sequence Diagrams into a Coloured Petri Net

Using a case study on the specification of an elevator controller, this paper presents an approach that can translate given UML descriptions into a Coloured Petri Net (CPN) model. The UML descriptions must be specified in the form of Use Cases and UML 2.0 Sequence Diagrams. The CPN model constitutes one single, coherent and executable representation of all possible behaviours that are specified by the given UML artefacts. CPNs consitute a formal modelling language that enables construction and analysis of scalable, executable models of behaviour. A combined use of UML and CPN can be useful in several projects. CPN is well supported by CPN Tools and the work we present here is aimed at building a CPN Tools front-end engine that implements the proposed translation.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BSAB/607/200

Microwave-Assisted Extraction of Ricinine from Ricinus communis Leaves

The alkaloid ricinine (3-cyano-4-methoxy-N-methyl-2-pyridone) is found in di erent parts of the Ricinus communis plant and is known to possess several bioactive properties, including strong antioxidant activity. In this study, a new microwave-assisted extraction (MAE) method was developed for the recovery of ricinine from R. communis leaves. The extraction variables studied were extraction temperature (between 125 C and 175 C), microwave power (between 500Wand 1000 W), extraction time (between 5 min and 15 min), extraction solvent (between 10% and 90% of EtOAc in MeOH), and solvent-to-sample ratio (between 25:1 mL and 50:1 mL of solvent per gram of the sample). On studying the e ects of extraction variables, both solvent and liquid-to-solid ratio were found to exhibit the highest e ects on ricinine recovery. A fast (15 min) microwave-assisted extraction method was developed (high temperatures can be applied because the stability of ricinine is proven in the literature), allowing for the recovery of ricinine from R. communis leaves. The study revealed that R. communis leaves had almost 1.5 mg g1 (dried weight) of ricinine