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Een afname van zes procent levend geboren kalveren van vaarzen tussen 1995 en 2010 was aanleiding voor nieuw sectoronderzoek. Uit de inventarisatie blijkt dat naast bekende factoren als draagtijd en geboorteverloop de regio waar het bedrijf is gehuisvest en het seizoen van afkalven zorgen voor opmerkelijke verschillen in levensvatbaarheid van kalveren.

At the end of August and the first two weeks of September 2011 dozens of veterinary practitioners reported to GD Veekijker (Animal Health Service) several dairy herds with cows with sudden decreased milk production, watery diarrhea and sometimes fever. In the beginning these reports came from the Eastern region of the Netherlands, after that also from the other three regions. The percentages of diseased herds per veterinary practice varied from a few till dozens per cent. Extensive bacteriological, virological and parasitological testing of the feces of sick cows did not reveal an infectious cause of the clinical problems. Recently, 50 stored blood samples of clinically diseased cattle were tested for the Schmallenbergvirus using a PCR, and 36% (18/50) tested positive. A large group of control cows (n=115) was also tested with the PCR and all cattle tested negative. Likely the Schmallenbergvirus was the primary cause of the clinical symptoms in the Dutch dairy herds. Further research will be done to confirm this. Eind augustus en in de eerste helft van september 2011 kwamen bij de GD Veekijker tientallen meldingen binnen van praktiserende dierenartsen over meerdere melkveebedrijven in hun praktijk met koeien met plotselinge melkproductiedaling, waterdunne diarree en soms ook koorts. In het begin kwamen deze meldingen vooral uit het oosten van Nederland, later ook uit andere regio's. De schattingen van percentages aangetaste bedrijven per praktijk liepen uiteen van enkele tot tientallen procenten. Uitgebreid bacteriologisch, virologische en parasitologisch onderzoek van de feces van zieke koeien leverde geen ziekteverwekker op. Later zijn vijftig bewaarde serumbloedmonsters van klinisch zieke koeien met behulp van een PCR getest op het Schmallenbergvirus. Bij 36 procent (18/50) van deze monsters is dit virus aangetoond, bij een grote groep controle-dieren (n=115) werd dit virus niet aangetoond.

An outbreak of hydranencephaly in aborted foetuses and newborn calves occurred following the 2007 epidemic of bluetongue serotype 8 (BTV8\net2006) in the Netherlands. In total 35 aborted foetuses and 20 live-born calves, submitted from September 2007 to May 2008, were examined pathologically. Foetuses with gestational ages between 4 and 9 months (mean 6.8 month) showed varying stages of cerebral malformation. Initial stages were cavitations in the cerebral hemispheres with massive destruction of neuroparenchyma, calcium deposits, and a phagocytic inflammatory response. Later stages showed distinct hydranencephaly, the cerebral hemispheres being almost completely replaced by fluid-filled sacs. In seven cases the cerebellum was affected as well, but brainstem structures were intact. Newborn calves with clinical signs of abnormal behaviour ('dummy calves'), circling, head pressing, incoordination, and blindness were seen from the end of January 2008. The calves were born between 2nd January and 16th March 2008. The calves were euthanized after 1 day up to 14 weeks (mean 4-7 weeks). Brain malformations in these calves were confined to the cerebrum and consisted of varying degrees of hydranencephaly. Spleen tissue was PCR-positive for bluetongue virus (BTV) in 21 of 35 foetuses and in 1 of 20 calves. A higher percentage of PCR-positives was found in foetuses aborted in early gestation than in late gestation, suggesting clearance of BTV during gestation. Fifteen of 33 dams of PCR-negative hydranencephalic foetuses or calves could be traced and all were BTV-seropositive, indicating a previous BTV infection. The timing of hydranencephaly cases in live-born calves during the first months of 2008 was consistent with infection in early gestation during the prior transmission season. Vertical transmission and teratogenic potential have previously been described for modified-live vaccines for bluetongue but are highly unusual for field strains of BTV, which raises the issue whether BTV8\net2006 or its ancestor has been cell- or laboratory-adapted in the past Het voorkomen van hydranencefalie bij verworpen en pasgeboren kalveren in aansluiting op de bluetongue serotype 8 (BTV8\\net2006)-epidemie in Nederland in 2007 wordt beschreven

Developers of Consumer Electronics (CE) devices face the problem of the ever increasing amount of software that needs to be developed. At the same time the time to market of their products needs to decrease. In other domains Component Based software development aids in solving the resulting problems. However, existing component frameworks fail to meet some of the requirements specific for the CE domain. In order to improve this situation a component-based framework has been developed. In this chapter we describe this framework and motivate the architectural choices. These choices are influenced by the requirements on the framework. Some of these requirements are specific for the CE domain, others are more general.

The guaranty of meeting the timing constraints during the design phase of real-time component-based embedded software has not been realized. To satisfy real-time requirements, we need to understand behaviour and resource usage of a system over time. In this paper, we address both aspects in detail by observing the influence of input data on the system behaviour and performance. We extend an existing scenario simulation approach that features the modelling of input parameter dependencies and simulating the execution of the models. The approach enables specification of the dependencies in the component models, as well as initialisation of the parameters in the application scenario model. This gives a component-based application designer an explorative possibility of going through all possible execution scenarios with different parameter initialisations, and finding the worst-case scenarios where the predicted performance does not satisfy the requirements. The identification of these scenarios is important because it avoids system redesign at the later stage. In addition, the conditional behaviour and resource usage modelling with respect to the input data provide more accurate prediction.

This work addresses the problem of predicting timing properties of multitasking component assemblies during the design phase. For real-time applications, it is of vital importance to guarantee that the timing requirements of an assembly are met. We propose a simulation-based approach for predicting the real-time behaviour of an assembly based on models of its constituent components. Our approach extends the scenario-based method in [J. Muskens et al. (2004)] by offering a system model that is tailored to the domain of real-time applications. Contributions of This work include the possibility to handle the following features: mutual exclusion, combinations of aperiodic and periodic tasks and synchronization constraints. The analytical approach we used in previous work cannot handle these features. Therefore, we introduce the simulation-based approach. Our simulator provides data about dynamic resource consumption and real-time properties like response time, blocking time and number of missed deadlines per task. We have validated our approach using a video-decoder application.

Component-based software construction is of much interest in software engineering due to its promise of black-box composition and independent deployment. Because of this black-box nature, users of components must be concerned with their trustworthiness, in particular when third parties are involved. Component certification is used to improve trust, usually relating the component to the party that made it. In order to support predictable assembly the certification procedure should also address extra-functional properties. In addition, certificates should remain valid across certain compositions. We present a certification procedure in the context of the ROBOCOP component architecture. We discuss specific requirements, introduce terminology and present a solution.

Embedded systems must be cost-effective. This imposesstrict requirements on the resource consumption of their applications. It is therefore desirable to be able to determine the resource consumption of applications as early as possible in its development. Only then, a designer is able to guarantee that an application will fit on a target device. In this paper we will present a method for predicting run-time resource resource consumption in multi-task component based systems based on a design of an application. In [5] we describe a scenario based resource prediction technique and show that it can be applied to non-pre-emptive non-processing resources, like memory. In this paper we extend this technique, which enables us to handle pre-emptive processing resources and their scheduling policies. Examples of these class of resources are CPU and network. For component based software engineering the challenge is to express resource consumption characteristics per component, and to combine them to do predictions over compositions of components. To this end, we propose a model and tools, for combining individual resource estimations of components. These composed resource estimations are then used in scenarios (which model run-time behavior) to predict resource consumption.

This paper presents an econometric study dealing with household demand for energy in the Netherlands. The main objective of the paper is to present an estimation of the actual impact of an already implemented energy tax introduced in the Netherlands in 1996. The approach differs from the existing literature in that (1) it uses panel data for the same period in which the tax was introduced; and (2) it estimates a demand function that controls for a large set of variables, such as outside temperature, type of house and of house insulation, household cooking behavior, and an extensive number of durable goods and electrical appliances. The study concludes that, in the short term, the energy tax had a small but significant impact on energy consumption in the Netherlands. Concretely, the yearly average demand reduction was of 8% for electricity and 4.4% for gas. Additionally, the influence of variables other than price and income on household energy demand is discussed. Using this information, the impact that the energy tax had on household energy use can be compared with the energy reduction that could have been achieved when using other policy instruments.

Resources of embedded systems, such as memory size and CPU power, are expensive and (usually) not extensible during the lifetime of a system. It is therefore desirable to be able to determine the resource consumption of an application as early as possible in the design phase. Only then, a designer is able to guarantee that an application will fit on a target device. Resource prediction is a technique to estimate theamount of consumed resources by analyzing the design and/or implementation of an application. In this paper we concentrate on predicting memory consumption in component-based applications. Component-based applications complicate resource predictions because resource consumption is spread across individual components. The challenge is to express resource consumption per component, and to combine them to do predictions over compositions of components. To that end, we propose a model in which individual resource estimations of components can be combined. These composed resource estimations are then used in scenarios (which model run-time behavior) to predict memory consumption of applications.

The Software Engineering discipline lacks the ability to evaluate software architectures. Here we describe a tool for software architecture analysis that is based on metrics. Metrics can be used to detect possible problems and bottlenecks in software architectures. Even though metrics do not give a complete evaluation of software architectures it is a useful analysis method. The Software Architecture Analysis tool can be applied to XMI output generated by a UML modelling tool. We have done this using Rational Rose.