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This paper introduces time stream Pétri nets (Ts treamPn), a model for the formal specification of multimedia synchronization scenarios. This new model extends time Pétri nets to formally describe the timed behaviour of multimedia objects and streams in asynchronous distributed systems. The proposed approach uses time intervals to label the arcs exiting from the places of the net, and typed transitions to define different firing rules. This model allows a complete and accurate specification of synchronization constraints between multimedia streams and can be used at different levels of granularity. 相似文献
94.
Yannick Schellander Marius Winter Maurice Schamber Fabian Munkes Patrick Schalberger Harald Kuebler Tilman Pfau Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(5):363-372
In this work, real-time ultraviolet photodetectors are realized through metal–semiconductor–metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) is used as semiconductor material and gold as metal electrodes. The readout of an individual sensor is implemented by a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. The photosensor and the transimpedance amplifier are both manufactured on glass substrates. The measured photosensor possesses a high responsivity R , a low response time t R E S , and a good noise equivalent power value NEP . 相似文献
95.
Sheikh Abdullah Al Nusayer Patrick Schalberger Holger Baur Florian Kleber Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(9):535-547
Active matrix prestressed microelectromechanical shutter displays enable outstanding optical properties as well as robust operating performance. The microelectromechanical systems (MEMS) shutter elements have been optimized for higher light outcoupling efficiency with lower operation voltage and higher pixel density. The MEMS elements have been co-fabricated with self-aligned metal-oxide thin-film transistors (TFTs). Several optimizations were required to integrate MEMS process without hampering the performance of both elements. The optimized display process requires only seven photolithographic masks with ensuring proper compatibility between MEMS shutter and metal-oxide TFT process. 相似文献
96.
Srivastava Rachna Gaudet Vincent C. Mitran Patrick 《Journal of Signal Processing Systems》2022,94(1):101-116
Journal of Signal Processing Systems - This paper describes a field-programmable gate array (FPGA) implementation of a fixed-point low-density lattice code (LDLC) decoder where the Gaussian mixture... 相似文献
97.
Journal of Logic, Language and Information - 相似文献
98.
Hassen Ait Atmane Abdelouahed Tounsi Fabrice Bernard 《International Journal of Mechanics and Materials in Design》2017,13(1):71-84
The novelty of this paper is the use of an efficient beam theory for bending, free vibration and buckling analysis of functionally graded material (FGM) beams on two-parameter elastic foundation. The present theory accounts for both shear deformation and thickness stretching effects by a parabolic variation of all displacements across the thickness, and satisfies the stress-free boundary conditions on the upper and lower surfaces of the beam without requiring any shear correction factor. Due to porosities, possibly occurring inside FGMs during fabrication, it is therefore necessary to consider the vibration, bending and buckling behaviors of beams having porosities in this work. The equation of motion for FGM beams is obtained through Hamilton’s principle. The closed form solutions are obtained by using Navier technique, and then fundamental frequencies are found by solving the results of eigenvalue problems. The validity of the present theory is investigated by comparing some of the present in literature. It can be concluded that the proposed theory is accurate and simple in solving the bending, free vibration and buckling behaviors of FGM sandwich beams. 相似文献
99.
Junying Min Patrick Seim Denis Störkle Lars Thyssen Bernd Kuhlenkötter 《International Journal of Material Forming》2017,10(5):729-739
A thermal model was built to account for the effects of geometrical parameters of sheet specimen, process parameters and material parameters on the temperature increase of the sheet specimen in Electricity-Assisted Incremental Sheet Forming (EISF). In the EISF, the local area of sheet specimen contacting with a forming tool is heated by direct current, which flows through the forming tool to the sheet specimen. EISF experiments of two high strength steel sheets were carried out to validate the thermal model. The thermal model can be integrated into the control program of EISF system to achieve more accurate temperature control. 相似文献
100.