Database systems are a key component behind many of today's computer systems. As a consequence, it is crucial that database systems provide correct and continuous service despite unpredictable circumstances, such as software bugs or attacks. This paper presents the design of Byzantium, a Byzantine fault-tolerant database replication middleware that provides snapshot isolation (SI) semantics. SI is very popular because it allows increased concurrency when compared to serializability, while providing similar behavior for typical workloads. Thus, Byzantium improves on existing proposals by allowing increased concurrency and not relying on any centralized component. Our middleware can be used with off-the-shelf database systems and it is built on top of an existing BFT library.

The richness of Late Jurassic vertebrates in Portugal is known since the 19th century by Paul Choffat, Henri Sauvage and other. The Kimmeridgian Guimarota fauna assemblage is the best known, followed by the fauna of Lourinhã formation. Here is presented an attempt to provide a checklist of the reptiles and amphibians of the Late Jurassic. Amphibia: Lissamphibia (Celtedens, cf. Marmorerpeton, Discoglossidae indet.). Chelonia: Eucryptodira (Pleurosternidae indet., Platychelyidae indet., Plesiochelys cf. etalloni, Plesiochelys choffati, Anosteirinae indet.). Squamata: Scincomorpha (Becklesius hoffstetteri; Paramacellodus sp., Saurillodon proraformis, S. henkeli, S. cf. obtusus). Squamata: Anguimorpha (Dorsetisaurus pollicidens, Parviraptor estesi). Crown Lepidosauromorpha (Marmoretta sp.). Choristodera: Cteniogenidae (Ctenogenys reedi). Sauropterygia: Plesiosauria: Cryptoclidoidea: Cryptoclididae indet. Crocodylomorpha (Lisboasaurus estesi, L. mitrocostatus). Crocodyliformes: Neosuchia (Machimosaurus hugii, Goniopholis cf. simus, Goniopholis baryglyphaeus, cf. Bernissartia, Atoposauridae, Theriosuchus guimarotae, cf. Alligatorium, Metriorhynchus sp.). Pterosauria (Rhamphorhynchus sp., Pterodactylus sp.). Dinosauria: Theropoda (Ceratosaurus sp. , Torvosaurus sp., Lourinhanosaurus antunesi, Allosaurus europaeus, Cf. Compsognathus sp., cf. Richardoestesia sp., Dromaeosaurinae indeter., Velociraptorinae indeter., cf. Archaeopteryx sp., aff. Paronychodon). Dinosauria: Sauropoda: Eusauropoda (Dinheirosaurus lourinhanensis, Lourinhasaurus alenquerensis, Lusotitan atalaiensis, Apatosaurus sp.). Dinosauria: Ornithischia: Thyreophora (Dacentrurus armatus, Stegosaurus sp., Dracopelta zbyszewskii). Dinosauria: Ornithischia: Ornithopoda (Phyllodon henkeli, Dryosaurus sp., Hypsilophodon sp., Alocodon kuehnei, Trimucrodon cuneatus, Draconyx loureiroi).

Background: Often, claims in Component-Based Development (CBD) are only sup-
ported by qualitative expert opinion, rather than by quantitative data. This contrasts
with the normal practice in other sciences, where a sound experimental validation of
claims is standard practice. Experimental Software Engineering (ESE) aims to bridge
this gap. Unfortunately, it is common to find experimental validation efforts that are
hard to replicate and compare, to build up the body of knowledge in CBD.

Objectives: In this dissertation our goals are (i) to contribute to evolution of ESE, in
what concerns the replicability and comparability of experimental work, and (ii) to ap-
ply our proposals to CBD, thus contributing to its deeper and sounder understanding.

Techniques: We propose a process model for ESE, aligned with current experimen-
tal best practices, and combine this model with a measurement technique called
Ontology-Driven Measurement (ODM). ODM is aimed at improving the state of prac-
tice in metrics definition and collection, by making metrics definitions formal and ex-
ecutable, without sacrificing their usability. ODM uses standard technologies that can
be well adapted to current integrated development environments.

Results: Our contributions include the definition and preliminary validation of a pro-
cess model for ESE and the proposal of ODM for supporting metrics definition and
collection in the context of CBD. We use both the process model and ODM to perform
a series experimental works in CBD, including the cross-validation of a component
metrics set for JavaBeans, a case study on the influence of practitioners expertise in
a sub-process of component development (component code inspections), and an ob-
servational study on reusability patterns of pluggable components (Eclipse plug-ins).
These experimental works implied proposing, adapting, or selecting adequate ontolo-
gies, as well as the formal definition of metrics upon each of those ontologies.

Limitations: Although our experimental work covers a variety of component models
and, orthogonally, both process and product, the plethora of opportunities for using
our quantitative approach to CBD is far from exhausted.

Conclusions: The main contribution of this dissertation is the illustration, through
practical examples, of how we can combine our experimental process model with
ODM to support the experimental validation of claims in the context of CBD, in a re-
peatable and comparableway. In addition, the techniques proposed in this dissertation
are generic and can be applied to other software development paradigms.

Software transactional memory (STM) is a promising programming model that adapts many concepts borrowed from the databases world to control concurrent accesses to memory (RAM) locations. In this paper we propose a new classification for the active states of a transaction; a new memory quiescing algorithm, to allow the safe transition of a memory block form transactional to non-transactional space; we compare word and object transactional grain units; and evaluate the cost of consistent state validation, arguing that this cost can be minimized by performing partial validation on problematic code regions.

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Thyreophoran dinosaurs have spike- and club-shaped osteoderms probably used for defensive weapons. The structural and histological variations have been little known. Here, we provide the comparisons of the internal structures in defensive weapons of ankylosaurs and stegosaurs, using spikes of a polacanthid (Gastonia) and a nodosaurid (Edmontonia), clubs of ankylosaurids (Saichania and Ankylosauridae indet. from Canada), and spikes of stegosaurids (Stegosaurus and Dacentrurus), which sheds light on understandings of evolutionary history and functional implications of defensive weapons in thyreophorans. In ankylosaurs, the structural and histological features of spikes and clubs are similar with those of small osteoderms in having thin compact bones, thick cancellous bones with large vascular canals, and abundant collagen fibers. A previous study demonstrated that each of three groups of ankylosaurs (polacanthid, nodosaurid, and ankylosaurid) has distinct characteristic arrangements of collagen fibers in small osteoderms. This study shows that spikes and clubs of ankylosaurs maintain the same characteristic features for each group despite of the differences in shapes and sizes. Conversely, the spike-shaped osteoderms in primitive (Dacentrurus) and derived (Stegosaurus) stegosaurids have similar structure to each other and are significantly different from the other types of stegosaur osteoderms (throat bony ossicles and plates) in having thick compact bones with a medullary cavity. These lack abundant collagen fibers unlike ankylosaur osteoderms. The spikes of ankylosaurs and stegosaurs are similar in shape, but their structural and histological features are different in having unique structures of collagen fibers for ankylosaurs and thick compact bones for stegosaurs, providing enough strength to have large spikes and to use them as defensive weapons. Although the shapes of ankylosaur clubs are different from spikes, the internal structures are similar, suggesting that ankylosaurs maintain similar structures despite of different shapes in osteoderms. These results indicate that ankylosaurs and stegosaurs used different strategies independently to evolve defensive weapons.

An European directive established that all EU countries must have, until the end of 2006, a recovery network for the electric and electronic equipment waste (WEEE). In Portugal, a group of producers formed a non-profit organization to design and manage this waste now. In this work, a model developed previously by the authors to design and plan a generic WEEE network is presented and applied to the Portuguese case. The results obtained are discussed and compared with the network that is currently operating.

As questões associadas aos processos de localização empresarial têm vindo a adquirir uma dimensão cada vez mais política do que apenas económica ou técnica. O desenvolvimento tecnológico tem vindo a facilitar uma maior amplitude de escolhas e de orientações relativas à localização das actividades empresariais. Mas o mesmo se passa com a deslocalização das mesmas. As consequências sociais podem ser igualmente importantes pois podem gerar processos de desagregação social, forte mobilidade territorial e, frequentemente, incremento de processos de desigualdade social.

This paper presents the mobile technology utilization in improving the remote access to the data acquisition processes of several automated monitoring system for air quality, water quality, and crop canopy microclimate. The system facilitates mobile environmental management and decision making by using in-situ measurements, GSM/GPRS informational fluxes, Pocket PCs, dGPS and mobile GIS resources. Data is retrieved via GSM/GPRS data modem to remote computer using digital (GSM) phone network. The main outcomes of this study were as follows: 1. designing the hardware, communication and software infrastructure of the system using telemetry features, 2. establishing the wireless connections and remote access from PDAs to the measurement servers, 3. programming and testing specific control virtual instruments (Vis) in NI LabVIEWTM, 4. obtaining a portable solution of statistical analysis and survey with PDA Vi (Virtual Instruments) interfaces for Pocket PC to gather, store, customize and report data combined with statistical processing functions, and 5. identifying mobile GIS applications for the environmental protection. The remote-accessing of the GIS server features, provided in-situ electronically reviews, mark up, and precise measurements of the site pollution plans. One possible solution to overcome the PDA hardware and software restraints is enabling the remote access and control of the DAQ and GIS software resources of the measurement server via internet.

Software transactional memory is a promising programming model that adapts many concepts borrowed from the databases world to control concurrent accesses to main memory (RAM). This paper discusses how to support revertible operations, such as memory allocation and release, within software libraries that will be used in software memory transactional contexts. The proposal is based in the extension of the transaction life cycle state diagram with new states associated to the execution of user-defined handlers. The proposed approach is evaluated in terms of functionality and performance by way of a use case study and performance tests. Results demonstrate that the proposal and its current implementation are flexible, generic and efficient

Software transactional memory (STM) is a promising programming model that adapts many concepts borrowed from the databases world to control concurrent accesses to main memory (RAM) locations. This paper aims at discussing how to support apparently irreversible operations within a memory transaction.

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Dinosaurs and other fossils have been artificially enhanced, or totally forged, to increase their commercial value. The most problematic forgeries to detect are based on original fossils that are artificially assembled. Several techniques are suggested for detecting hoaxes: detailed visual examination, chemical analysis, Xray or CT-scan, and ultraviolet light. It is recommended that museums and paleontological researchers do not purchase and/or trade fossils lacking clear provenience information. Exceptions to that general rule should be closely examined using techniques described herein.

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