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Synchronous programming is available through several formally defined languages having very different characteristics: Esterel is imperative, while Lustre and Signal are declarative in style; Statecharts and Argos are graphical languages that allow one to program by constructing hierarchical automata. Our motivation for taking the synchronous design paradigm further, integrating imperative, declarative (or dataflow), and graphical programming styles, is that real systems typically have components that match each of these profiles. This paper motivates our interest in the mixed language programming of embedded software around a number of examples, and sketches the semantical foundation of the Synchronie toolset which ensures a coherent computational model. This toolset supports a design trajectory that incorporates rapid prototyping and systematic testing for early design validation, an object oriented development methodology for long term software management, and formal verification at the level of automatically generated object code.  相似文献   
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In the realization step of any microstrip filter according to the required electrical characteristics, coupling factors and external quality factor (Qext) are related to the physical parameters of the structure using time consuming full wave simulations. This paper presents a simple, fast, and accurate parametric model of the coupling between the coupled square open loop resonators (SOLRs) and Qext of these resonators versus physical parameters of the structure and substrate characteristics utilizing active learning method (ALM). In the modeling process the multi-dimensional functions of coupling factor and Qext are broken down into their simpler aspects, their behaviors are extracted and then final model will be constructed by combining these simpler aspects. ALM allows the overall model for coupling factor and Qext to be developed through the use of small number of initial data. Once the modeling process is completed it provides a fast and accurate prediction of the required physical parameters for a given coupling factor and Qext. Using the constructed model for a distinct SOLR, which its accuracy was validated by comparison with the full wave simulation results a filter was designed and fabricated. Good agreement between measured and simulated response confirms the accuracy of the modeling procedure.  相似文献   
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Electronic Markets - Physical inactivity is a global public health problem that poses health risks to individuals and imposes financial burdens on already strained healthcare systems. Wearables...  相似文献   
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Calcination is a thermo-chemical process, widely used in the cement industry, where limestone is converted by thermal decomposition into lime CaO and carbon dioxide CO2. The focus of this paper is on the implementation and validation of the endothermic calcination reaction mechanism of limestone in a commercial finite volume based CFD code. This code is used to simulate the turbulent flow field, the temperature field, concentrations of the reactants and products, as well as the interaction of particles with the gas phase, by solving the mathematical equations, which govern these processes. For calcination, the effects of temperature, decomposition pressure, diffusion and pore efficiency were taken into account. A simple three-dimensional geometry of a pipe reactor was used for numerical simulations. To verify the accuracy of the modelling approach, the numerical predictions were compared with experimental data, yielding satisfying results and proper trends of physical parameters influencing the process.  相似文献   
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Manufacturing of chemical‐pharmaceutical products is moving increasingly fast on a global scale. Therefore, developing and starting up production facilities fast, with high quality, and at reasonable costs has become extremely challenging. Engineering concepts like modularization, standardization and simultaneous/parallel engineering are discussed as methods for speeding up process design and filing for regulatory approval. Transfer from batch to continuous operation mode of production is pointed out as the key‐issue in such strategies.  相似文献   
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