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排序方式: 共有2993条查询结果,搜索用时 15 毫秒
31.
Gerhard Szczuka 《电子与电脑》2009,(3)
多核处理器为嵌入式计算应用带来巨大的性能优势.这使得具有成本效益和紧凑平台的SMP(对称多处理器)平台和运行不同操作系统的二合一混合平台的开发成为可能.现在,随着全新45nm工艺的双核处理器的到来,预示着嵌入式计算解决方案向下一阶段演进.相比65nm Intel core 2 Duo处理器,更低功耗的45nm Intel Core2 Duo SP9300处理器可以提供更快的核心速度,二级缓存增加50%、前端总线频率提升25%. 相似文献
32.
Giuseppe Cantarella Vincenzo Costanza Alberto Ferrero Raoul Hopf Christian Vogt Matija Varga Luisa Petti Niko Münzenrieder Lars Büthe Giovanni Salvatore Alex Claville Luca Bonanomi Alwin Daus Stefan Knobelspies Chiara Daraio Gerhard Tröster 《Advanced functional materials》2018,28(30)
In the field of flexible electronics, emerging applications require biocompatible and unobtrusive devices, which can withstand different modes of mechanical deformation and achieve low complexity in the fabrication process. Here, the fabrication of a mesa‐shaped elastomeric substrate, supporting thin‐film transistors (TFTs) and logic circuits (inverters), is reported. High‐relief structures are designed to minimize the strain experienced by the electronics, which are fabricated directly on the pillars' surface. In this design configuration, devices based on amorphous indium‐gallium‐zinc‐oxide can withstand different modes of deformation. Bending, stretching, and twisting experiments up to 6 mm radius, 20% uniaxial strain, and 180° global twisting, respectively, are performed to show stable electrical performance of the TFTs. Similarly, a fully integrated digital inverter is tested while stretched up to 20% elongation. As a proof of the versatility of mesa‐shaped geometry, a biocompatible and stretchable sensor for temperature mapping is also realized. Using pectin, which is a temperature‐sensitive material present in plant cells, the response of the sensor shows current modulation from 13 to 28 °C and functionality up to 15% strain. These results demonstrate the performance of highly flexible electronics for a broad variety of applications, including smart skin and health monitoring. 相似文献
33.
Gerhard Heise Andreas Brner Marcel Dickmann Marina Englmaier Andreas Heiss Matthias Kemnitzer Jan Konrad Regina Moser Jrg Palm Helmut Vogt Heinz P. Huber 《Progress in Photovoltaics: Research and Applications》2015,23(10):1291-1304
In this paper, we present the selective structuring of all three patterns (P1, P2 and P3) of a monolithic interconnection of CIS (Cu(In,Ga)(S,Se)2) thin film solar cells by picosecond laser pulses at a wavelength of 1064 nm. We show results for single pulse ablation threshold values and line scribing of molybdenum films on glass (P1), CIS on molybdenum (P2) and zinc oxide on CIS (P3). The purposes of these processes are the p‐type isolation (P1), cell interconnect (P2) and n‐type isolation (P3), which are required for complete cell architecture. The half micron thick molybdenum back electrode can be structured with a process speed of more than 15 m/s at about 15 W average power without detectable residues and damage by direct induced laser ablation from the back side (P1). The CIS layer can be structured selectively down to the molybdenum at process speeds up to 1 m/s at about 15 W average power, due to the precision of direct laser ablation in the ultrashort pulse regime (P2). The ZnO front electrode layer is separated by clean trenches with straight side walls at process speeds of up to 15 m/s at about 10 W average power, as a result of indirect induced laser ablation (P3). A validation of functionality of all processes is demonstrated on CIS solar cell modules (30 × 30 cm2). By replacing one state‐of‐the‐art process by a picosecond laser process at a time, solar efficiencies could be increased for P1 and P2 and stayed on a similar level for P3. After an optimization of the patterning processes in the R&D pilot line of AVANCIS, we achieved a new record efficiency for an all‐laser‐patterned CIS solar module: 14.7% as best value for the aperture area efficiency of a 30 × 30 cm2 sized CIS module was reached. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
34.
Hendrik Voigt Aaron Rigoni Evgeniy Boltynjuk Mohammed Reda Chellali Bonnie Tyler Harald Rösner Sergiy Divinski Horst Hahn Gerhard Wilde 《Advanced functional materials》2023,33(44):2302386
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. 相似文献
35.
Nadobny J Szimtenings M Diehl D Stetter E Brinker G Wust P 《IEEE transactions on bio-medical engineering》2007,54(10):1837-1850
An investigation of magnetic resonance (MR)-induced hot spots in a high-resolution human model is performed, motivated by safety aspects for the use of MR tomographs. The human model is placed in an MR whole body resonator that is driven in a quadrature excitation mode. The MR-induced hot spots are studied by varying the following: (1) the temporal specific absorption rate (SAR) mode ("steady imaging", "intermittent imaging"), (2) the simulation procedure (related to given power levels or to limiting temperatures), and (3) different thermal tissue properties including temperature-independent and temperature-dependent perfusion models. Both electromagnetic and thermodynamic simulations have been performed. For the electromagnetic modeling, a commercial finite-integration theory (FIT) code is applied. For the thermodynamic modeling, a time-domain finite-difference (FD) scheme is formulated that uses an explicit treatment of temperature gradient components. This allows a flux-vector-based implementation of heat transfer boundary conditions on cubical faces. It is shown that this FD scheme significantly reduces the staircase errors at thermal boundaries that are locally sloped or curved with respect to the cubical grid elements. 相似文献
36.
Dirty RF: A New Paradigm 总被引:1,自引:0,他引:1
Gerhard Fettweis Michael Löhning Denis Petrovic Marcus Windisch Peter Zillmann Wolfgang Rave 《International Journal of Wireless Information Networks》2007,14(2):133-148
The implementation challenge for new low-cost low-power wireless modem transceivers has continuously been growing with increased
modem performance, bandwidth, and carrier frequency. Up to now we have been designing transceivers in a way that we are able
to keep the analog (RF) problem domain widely separated from the digital signal processing design. However, with today’s deep
sub-micron technology, analog impairments – “dirt effects” – are reaching a new problem level which requires a paradigm shift
in the design of transceivers. Examples of these impairments are phase noise, non-linearities, I/Q imbalance, ADC impairments,
etc. In the world of “Dirty RF” we assume to design digital signal processing such that we can cope with a new level of impairments,
allowing lee-way in the requirements set on future RF sub-systems. This paper gives an overview of the topic and presents
analytical evaluations of the performance losses due to RF impairments as well as algorithms that allow to live with imperfect
RF by compensating the resulting error effects using digital baseband processing. 相似文献
37.
Gerhard Jank 《Multidimensional Systems and Signal Processing》2006,17(2-3):257-270
We consider disturbed linear 2D-systems of Fornasini–Marchesini type in the continuous time case. These systems are also named
Goursat-type systems. Conditions for unique solvability of the disturbed optimal control problem with a quadratic cost functional
are obtained. The disturbed or worst case optimal control guarantees to minimize the cost functional for any unknown disturbance
input. In a second part then we consider a disturbance attenuation by boundary controls, i.e., by using the Goursat-data as
control functions. In the 2D-case this results in two control functions acting independently on the system. We study a cooperative
and a non-cooperative situation. In the cooperative situation we again obtain a disturbed optimal control problem and get
conditions for existence and uniqueness of such a disturbed optimal control problem. If the action of the agents is non-cooperative
we assume that it is agreed that they act on an open-loop Nash/worst-case equilibrium strategy. Sufficient conditions for
the existence of such an equilibrium are obtained.
Published online: April 2006 相似文献
38.
Bastian?RistauEmail author Torsten?Limberg Gerhard?Fettweis 《Journal of Signal Processing Systems》2009,57(1):45-56
The computational demand of signal processing algorithms is rising continuously. Heterogeneous embedded multiprocessor systems-on-chips
are one solution to satisfy this demand. But to be able to take advantage of these systems, new strategies are required to
map applications to such a system and to evaluate the systems performance at a very early design stage. We will present a
framework for static, analytical, bottom-up temporal and spatial mapping of applications to MPSoCs based on packing. This
mapping framework allows easy performance evaluation and design space exploration of heterogeneous systems on chip.
相似文献
Gerhard FettweisEmail: |
39.
Gerhard Buchbauer Leopold Jirovetz Michael Wasicky Anton Herlitschka Alexej Nikiforov 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1994,199(1):1-4
Zusammenfassung Mittels Headspace-Analyse in Kombination mit gaschromatographisch-spektroskopischen Methoden (GC-FID und GC-FTIR-MS), sowie der GC-Schnüffel-Technik gelang es, Blüten verschiedener Weinsorten (sieben verschiedene Weißweinspecies) anhand der Duftstoff-Zusammensetzung bezüglich duftbestimmender Sesquiterpene und duftabrundender Monoterpene im Headspace zu korrelieren.-Alle untersuchten Weinblüten besitzen einen reseda-artigen, schönen, blumigen, staubigen, trockenen, angenehmen, interessanten, grünen, frischen, intensiven und süßen Duft wobei sich die einzelnen Blüten, je nach Weinsorte, lediglich in der Intensität der Einzeldüfte, nicht aber in der Gesamtduftrichtung unterscheiden. Die erstellten Geruchsprofile und die entsprechenden multivariaten Korrelationen dieser Profile zeigten eine weitgehende Übereinstimmung mit jenen Ergebnissen, die aus den Headspace-Inhaltsstoffkorrelationen der einzelnen Blütensorten erhalten werden konnten. -Die Möglichkeiten weiterer Zusammenhänge mit entsprechenden ampelographischen Aspekten der untersuchten Weinsorten werden diskutiert.
Aroma of white vine blossoms: correlation of sensoric data with headspace constituents
Using headspace-analysis in combination with gaschromatographic-spectroscopic methods (GC-FID and GC-FTIR-MS) as well as with the GC-sniffing-technique it was possible to correlate blossoms of 7 different vine-varieties by means of the composition of odor compounds in their headspace considering only odor-dominant sesquiterpenes and odor-assistant monoterpenes. -All investigated vineblossoms possess a mignonette-like, pleasant, floral, dusty, dry, interesting, green, fresh, intense and sweet odour and with regard to the vine-species they only differ in the intensity of single odournotes, but not in the direction of the total odour. The odour-profiles and the corresponding multivariate data analysis of these profiles showed a significant agreement with those results, which were obtained by correlations of headspace constituents. -The possibility of further connectivities with the corresponding ampelographic aspects of the investigated vine-species is also discussed.相似文献
40.