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Runtime Contracts Checker: Increasing Robustness of Component-Based Software Systems
Get PDFSoftware Systems are becoming increasingly complex leading to new Validation &Verification challenges. Model checking and testing techniques are used at development time while runtime verification aims to verify that a system satisfies a given property at runtime. This second technique complements the first one. This paper presents a runtime contract checker (RCC) which checks a component-based software system's contracts defined at design phase. We address embedded systems whose software components are designed by Unified Modelling Language-State Machines (UML-SM) and their internal information can be observable in terms of model elements at runtime. Our previous research work, CRESCO (C++ REflective State-Machines based observable software COmponents) framework, generates software components that provide this observability. The checker uses software components' internal status information to check system level safety contracts. The checker detects when a system contract is violated and starts a safeStop process to prevent the hazardous scenario. Thus, the robustness of the system is increased
Elektrospinning bidezko PCL nanozuntzen lorpena larruazal-birsorkuntzarako
Get PDFSkin ulcers are a serious threat to public health system, and, although wound healing is a natural process, a proper dressing can improve the healing process. In this work, platelet rich plasma (PRP) coated polycaprolactone (PCL) wound dressings have been designed by means of electrospinning. PCL is a biocompatible and biodegradable synthetic polymer. PRP, in turn, offers growth factors to the dressing, which are significant in the healing. To enable an effective addition of PRP, functionalization of PCL fibre meshes has been carried out by immersing them in alkaline dissolution of different concentrations. In this way, a novel wound dressing that aids in the regeneration of damaged skin layers has been developed.Larruazal-ultzerak osasun publikoarentzat mehatxu larriak dira, eta zaurien orbaintzea prozesu naturala bada ere, zauri-jantzi egoki batek prozesuan lagundu dezake. Lan honetan, elektrospinning teknika bitartez, polikaprolaktonazko (PCL) zauri-jantziak diseinatu dira, zeinei plaketan aberatsa den plasma (PRP) estaldura gehitu zaie. PCL biobateragarria eta biodegradagarria den polimero sintetikoa da. PRPak aldiz, lesioa sendatzeko oso garrantzitsuak diren hazkunde-faktoreak eskaintzen dizkio zauri-jantziari. PRParen adizio eraginkorra ahalbidetzeko, PCLezko zuntz-sareen funtzionalizazioa burutu da hau kontzentrazio desberdineko disoluzio alkalinoetan murgilduz. Horrela, kaltetutako azalgeruzen birsortzea eragingo duen zauri-jantzia garatu da
Induction Skull Melting of Ti-6Al-4V: Process Control and Efficiency Optimization
Get PDFTitanium investment casting is one of the leading and most e cient near-net-shape manufacturing processes, since complex shape components are possible to obtain with a very low amount of material waste. But melting these reactive alloys implies the usage of specific melting technologies such as the Induction Skull Melting (ISM) method. In this work the ISM was extensively studied with the aim of deepening the characteristics of this specific melting method and improving the too low energy e ciency and overall process performance. A 16 segment copper crucible and 3 turns coil was employed for the melting of 1 kg of Ti-6Al-4V alloy. Through the calorimetric balance, real-time evolution of the process parameters and power losses arising from the crucible and coil sub-assemblies was displayed. Results revealed the impact of coil working conditions in the overall ISM thermal efficiency and titanium melt properties, revealing the use of these conditions as an effective optimization strategy. This unstudied melting control method allowed more heat into charge and 13% efficiency enhancement; leading to a shorter melting process, less energy consumption and increased melt superheat, which reached 49 ºC. The experimental data published in this paper represent a valuable empiric reference for the development and validation of current and future induction heating models
Development of a Modular Fretting Wear and Fretting Fatigue Tribometer for Thin Steel Wires: Design Concept and Preliminary Analysis of the Effect of Crossing Angle on Tangential Force
Get PDFThis work presents the design of a modular ad-hoc fretting fatigue and fretting wear tribotester for thin steel wires. The working principles of the diffrent modules are described, such as the displacement and contact modules. Preliminary studies for understanding the effect of crossing angle between wires on tangential force measurement has been carried out on 0.45 mm diameter cold-drawn eutectoid carbon steel (0.8% C). The results show that due to the developed wear scar geometry for high crossing angles there is a non-Coulomb behaviour that is not seen for low crossing angles
DFA-SPDP, a new DFA method to improve the assembly during all the product development phases
Get PDFDesign for Assembly (DFA) methodologies help the designer to take into account the assembly process during the development phases of a product (specifications, conceptual design and detailed design), thus improving the assembly process of the product. After a bibliographic review, it is verified that the most extended DFA methodologies are: Boothroyd-Dewhurst method, Lucas method, Hitachi AEM method and Modified Westinghouse method. All these methodologies help to achieve improvements in some of the development phases, but none of them assist the designer in all the phases of the process.
This article presents a DFA methodology that considers the assembly process of a product during all the phases of its development (DFA-SPDP). For this purpose, DFA-SPDP method is created from the four most widespread methodologies. This methodology brings together the main quantitative parameters of the four methodologies in a single method. As a conclusion, applying DFA-SPDP method, the designer is supported throughout the process of developing a product, with information equivalent to that resulting from the application of the four methodologies
Lack of association of cranial lacunae with intracranial hypertension in children with Crouzon syndrome and Apert syndrome: a 3D morphometric quantitative analysis
Get PDFPurpose Cranial lacunae (foci of attenuated calvarial bone) are CT equivalents ofBcopper beating seen on plain skull radio-graphs in children with craniosynostosis. The qualitative presence of copper beating has not been found to be useful for the diagnosis of intracranial hypertension (IH) in these patients. 3D morphometric analysis (3DMA) allows a more systematic and quantitative assessment of calvarial attenuation. We used 3DMA to examine the relationship between cranial lacunae and IH in children with Crouzon and Apert syndromic craniosynostosis
MDE based IoT Service to enhance the safety of controllers at runtime
Get PDFOne of the challenges for complex IoT software systems is toincrease their safety. A Model Driven Development approach helps in the design and development phase of these systems while runtime checkin gtechniques help to enhance safety. To supervise the status of different IoT services that are registered in a local cloud at runtime, the solution that is presented in this work uses the information that it receives from the different services registered in a local cloud in model terms. The runtime checker, the new Safety related service of the Arrowhead framework, has predefined contracts to ensure the correctness of the services at runtime.Based on these contracts and checking the information that it receives at runtime it is able to detect unsafe scenarios. Once an unsafe scenario is detected, it starts a safe process to protect the behaviour of the whole system adapting the wrong service or services to a degraded operation mode at runtime. All these services will be Arrowhead compliant
Virtual commissioning of a robotic cell: an educational case study
Get PDFThe emergence of software tools for testing control programs and virtual commissioning (VC) in industrial automation projects makes it possible to shorten lead times and improve product quality, but it also brings to light the need for competent technicians in these technologies. The academic environment can support the education of future professionals by reproducing and solving industrial problems in the classroom. This article presents a use case in which students work on a project to develop and validate the control system of a robotic cell. The study compares the conventional way of working against the use of a digital twin and exposes the benefits of it
Observatorio de la competitividad Pyme 2020. Informe sobre prácticas competitivas: Las empresas de servicios avanzados en Bilbao. Volumen 1
No full textEn el ámbito de la innovación y la mejora de la competitividad de las empresas, los servicios intensivos en conocimiento o KIBS (atendiendo a sus siglas en inglés) juegan un
papel esencial en la mejora de los procesos y las actividades
clave de las empresas-cliente. Este hecho, cobra mayor relevancia en el contexto económico actual, donde la crisis
industrial empuja a replantearse los modos de hacer tradicionales de las pequeñas y medianas empresas de nuestro
entorno local, para poder ser competitivas a escala global.
Este fenómeno está también muy presente en Bizkaia, donde en las últimas décadas el sector servicios ha ido ganando
en importancia frente al sector industrial. Incluso en la propia industria existe una tendencia muy marcada a incorporar una capa de servicios de gran valor añadido al propio
producto como vía para aumentar el valor de las ofertas en
el mercado (Baines y Lightfoot, 2013), a esta última tendencia se le denomina servitización
Sandwich biskoelastikoen nukleoaren lodieraren eragina igogailu baten erantzun dinamikoan
Get PDFThe use of thin viscoelastic sandwiches in terms of vibration attenuation has been widely validated. Sandwich structures composed of viscoelastic adhesive films and metallic constraining layers result in thin composite structures with improved dynamic capabilities. Due to the viscoelastic core, the damping capacity of the sandwich is considerably increased compared to metallic panels. In this work, a numeric model of a lift using viscoelastic sandwiches is presented, in order to evaluate the influence of the core thickness on the dynamic response of a lift. The results show that the thickness of the viscoelastic film determines the vibrational response of the lift.Bibrazioak ahultzeko helburuarekin sandwich biskoelastiko meheen erabilera zabalki balioztatua izan da. Mintz itsasgarri biskoelastikoz eta azal metalikoz osaturiko sandwich egiturek ezaugarri dinamiko hobetuak dituzten konposite egitura meheak osatzen dituzte. Nukleo biskoelastikoari esker, sandwicharen moteltze gaitasuna asko handitzen da, panel metaliko soilekin konparatuz. Lan honetan, igogailu baten zenbakizko eredua aurkezten da, sandwich biskoelastikoak erabiliz nukleoaren lodierak igogailuaren erantzun dinamikoan duen eragina aztertzeko helburuarekin. Analisiaren emaitzek mintz biskoelastikoaren lodierak igogailuaren erantzun bibrakorra zehazten duela erakusten dute