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161.
Rodrigo F. P. Martins Arman Ahnood Nuno Correia Luís M. N. P. Pereira Raquel Barros Pedro M. C. B. Barquinha Ricardo Costa Isabel M. M. Ferreira Arokia Nathan Elvira E. M. C. Fortunato 《Advanced functional materials》2013,23(17):2153-2161
The ability to process and dimensionally scale field‐effect transistors with and on paper and to integrate them as a core component for low‐power‐consumption analog and digital circuits is demonstrated. Low‐temperature‐processed p‐ and n‐channel integrated oxide thin‐film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low‐cost, recyclable paper substrates. The possibility of building these circuits using low‐temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low‐power circuitry with a recyclable substrate is an important step towards greener electronics. 相似文献
162.
163.
Ricardo Carelli Guillermo Forte Luis Canali Vicente Mut Gastn Aragus Eduardo Destfanis 《Mechatronics》2008,18(4):187-194
The present work proposes an autonomous tracking control system and a control structure to combine autonomous and teleoperation commands in a bicycle-type mobile robot. This compounded operation renders great flexibility to the control system of the mobile robot. For autonomous operation, a simple tracking controller that includes compensation of the robot dynamics is developed. This tracking control system is proved to be stable in the sense that it asymptotically reaches the tracking objective. Teleoperation with visual access to the robot’s workspace is integrated via a joystick with the autonomous operation of the robot. Simulations and experimental results on a prototype robot show the feasibility and performance of the proposed control system. 相似文献
164.
Behavioural models for distributed Fractal components 总被引:2,自引:0,他引:2
Tomás Barros Rabéa Ameur-Boulifa Antonio Cansado Ludovic Henrio Eric Madelaine 《电信纪事》2009,64(1-2):25-43
This paper presents a formal behavioural specification framework for specifying and verifying the correct behaviour of distributed Fractal components. The first contribution is a parameterised and hierarchical behavioural model called pNets that serves as a low-level semantic framework for expressing the behaviour of various classes of distributed languages and as a common internal format for our tools. Then, we use this model to define the generation of behavioural models for applications ranging from sequential Fractal components, to distributed objects, and finally to distributed components. Our models are able to characterise both functional and non-functional behaviours and the interaction between the two concerns. Finally, this work has resulted in the development of tools allowing the non-expert programmer to specify the behaviour of his components and (semi)automatically verify properties of his application. 相似文献
165.
Clément?DuhartEmail authorView authors OrcID profile Pierre?Sauvage Cyrille?Bertelle 《International Journal of Wireless Information Networks》2016,23(3):173-186
Current Internet of Things (IoT) development requires service distribution over Wireless Sensor and Actor Networks (WSAN) to deal with the drastic increasing of network management complexity. Because of the specific constraints of WSAN, some limitations can be observed in centralized approaches. Multi-hop communication used by WSAN introduces transmission latency, packet errors, router congestion and security issues. As it uses local services, a model of decentralized services avoids long path communications between nodes and applications. But the two main issues are then to design (1) the composition of such services and to map (2) them over the WSAN. This contribution proposes a model for decentralized services based on Resource Oriented Architecture in which their communications are designed thanks to an adaptation of Petri Network (1). In addition, the problem of decentralized service mapping and its deployment over a WSAN is successfully resumed by a Pseudo-Boolean Optimization in order to minimize network communication load (2). These contributions are presented using a proposed EMMA middleware as unifying thread. 相似文献
166.
Andreia G. Macedo Rute A. S. Ferreira Duarte Ananias Mário S. Reis Vitor S. Amaral Luís D. Carlos João Rocha 《Advanced functional materials》2010,20(4):624-634
There is a growing interest in understanding how size‐dependent quantum confinement affects the photoluminescence efficiency, excited‐state dynamics, energy‐transfer and thermalization phenomena in nanophosphors. For lanthanide (Ln3+)‐doped nanocrystals, despite the localized 4f states, confinement effects are induced mostly via electron–phonon interactions. In particular, the anomalous thermalization reported so far for a handful of Ln3+‐doped nanocrystals has been rationalized by the absence of low‐frequency phonon modes. This nanoconfinement may further impact on the Ln3+ luminescence dynamics, such as phonon‐assisted energy transfer or upconversion processes. Here, intriguing and unprecedented anomalous thermalization in Gd2O3:Eu3+ and Gd2O3:Yb3+,Er3+ nanotubes, exhibiting up to one order of magnitude larger than previously reported for similar materials, is reported. This anomalous thermalization induces unexpected energy transfer from Eu3+ C2 to S6 crystallographic sites, at 11 K, and 2H11/2 → 4I15/2 Er3+ upconversion emission; it is interpreted on the basis of the discretization of the phonon density of states, easily tuned by varying the annealing temperature (923–1123 K) in the synthesis procedure, and/or the Ln3+ concentration (0.16–6.60%). 相似文献
167.
Reliable microaneurysm detection in digital fundus images is still an open issue in medical image processing. We propose an ensemble-based framework to improve microaneurysm detection. Unlike the well-known approach of considering the output of multiple classifiers, we propose a combination of internal components of microaneurysm detectors, namely preprocessing methods and candidate extractors. We have evaluated our approach for microaneurysm detection in an online competition, where this algorithm is currently ranked as first, and also on two other databases. Since microaneurysm detection is decisive in diabetic retinopathy (DR) grading, we also tested the proposed method for this task on the publicly available Messidor database, where a promising AUC 0.90 ± 0.01 is achieved in a "DR/non-DR"-type classification based on the presence or absence of the microaneurysms. 相似文献
168.
Superconducting tapes of YBCO-123 were produced by melt-annealing method on metallic Ni%5W substrates. YBCO thick films of about thick were deposited on Ni%5W tapes previously CeO2 coated using different thermal treatments. A final architecture of the tapes like Ni%5W/CeO2/YBCO/Au-Pd was achieved.Critical temperatures (Tc) of the superconducting tapes around 89 K and critical current densities (Jc) of at 77 K and were determined by resistive methods. All the samples displayed a granular character and the crystalline structure of the superconducting YBCO-123 with and preferential orientation along the c-axis as determined by SEM and XRD analysis, respectively. Both grain sizes and c-axis orientation are dependent of the thermal treatments. 相似文献
169.
170.
I. Cortés G. Toulon F. Morancho E. Hugonnard-Bruyere B. Villard W.J. Toren 《Microelectronics Reliability》2012,52(3):503-508
This paper is focused on the analysis and optimization of power N-type LDMOS (LDNMOS) transistors (VBR > 120 V) with the purpose of being integrated in a new generation of Smart-Power technology based upon a 0.18 μm SOI-CMOS technology. The influence of some important design parameters such as the shallow trench isolation (STI) length (LSTI), the N-well doping profile and the relative position of the N-well mask to the STI block are analyzed in terms of voltage capability (VBR), specific on-state resistance (Ron-sp) and electrical safe-operating area (SOA) by means of Technology Computer-Aided Design (TCAD) numerical simulations. The evolution of the measured and simulated VBR as a function of the substrate (handle wafer) voltage (HWV) gives good physical insight of the optimal LDNMOS drift region design configuration. LDNMOS transistors with STI lengths partially covering the drift region length leads to better combined action of Ron-sp/VBR trade-off and electrical SOA results. 相似文献