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191.
Jan De Cock Stijn Notebaert Kenneth Vermeirsch Peter Lambert Rik Van de Walle 《Multimedia Systems》2010,16(2):139-149
In this paper, we examine spatial resolution downscaling transcoding for H.264/AVC video coding. A number of advanced coding
tools limit the applicability of techniques, which were developed for previous video coding standards. We present a spatial
resolution reduction transcoding architecture for H.264/AVC, which extends open-loop transcoding with a low-complexity compensation
technique in the reduced-resolution domain. The proposed architecture tackles the problems in H.264/AVC and avoids visual
artifacts in the transcoded sequence, while keeping complexity significantly lower than more traditional cascaded decoder–encoder
architectures. The refinement step of the proposed architecture can be used to further improve rate-distortion performance,
at the cost of additional complexity. In this way, a dynamic-complexity transcoder is rendered possible. We present a thorough
investigation of the problems related to motion and residual data mapping, leading to a transcoding solution resulting in
fully compliant reduced-size H.264/AVC bitstreams. 相似文献
192.
在战争的演化模型的研究中,为了控制和引导社会舆论,民众战争态度演化是战争复杂系统研究的莺要内容之一.考虑持不同战争态度的社会个体之间的相互作用率与其态度距离的关系和从众心理,提出了度量持不同态度社会个体相遇的相互作用率.分析了态度演化的三种过程,确定了不同态度之间转变的转移概率密度,建立了战争态度演化的动力学方程模型.引入一个序参量度量持各种战争态度人数的动态变化,定义了战争态度构型演化的相.仿真结果表明,得到外界支持的态度,最终持有的人数在社会中占多数,外界作用对社会民众态度转变,对大多数人是有效的,但有极少数人仍会坚持原来的态度. 相似文献
193.
194.
Jan Mulkens Bob Streefkerk Hans Jasper Jos de Klerk Fred de Jong Leon Levasier Martijn Leenders 《电子工业专用设备》2008,37(3):13-19
论述了第五世代双扫描平台浸液式扫描曝光机的性能和进展。表明了在高速扫描状态下有生产价值的套刻和聚焦性能的实现。浸液式设备更多的关键部分与缺陷有关,而且该机的改进是通过有生产价值的缺陷水平方面来体现的。为了保持这种缺陷水平的改进效果,需要在圆片应用中进行专门稳定的测量。特加是边缘空泡除去(EBR)设计和圆片斜面良流线性是很重要的。 相似文献
195.
196.
Emanuele Bertarelli Alberto Corigliano Andreas Greiner Jan G. Korvink 《Microsystem Technologies》2011,17(1):165-173
A novel design strategy to avoid pull-in occurrence in electrostatic micro electro mechanical systems is proposed. It combines
charge control with ring electrodes, on a circular geometry. This idea is introduced here for the design of efficient and
reliable high stroke electrostatic diaphragm micropumps, while it has a broad potential applicability. A minimal lumped one
degree-of-freedom model is derived and used to introduce and demonstrate the proposed approach for a circular plate geometry.
Finite element models are subsequently adopted for a more detailed device modelling. As expected, charge control exhibits
a stabilizing effect with respect to voltage drive, but not sufficient to achieve a full-range stability for the considered
geometry. When the electrode area is properly defined, stability range can be extended up to gap closure in the central part
of the membrane. In this configuration, the increase in voltage required for full-range device drive would be relevant, while
in charge control the penalty is considerably lower. Finally, loading conditions and geometrical parameters for an optimized
actuation are suggested. 相似文献
197.
Constant folding is a well-known optimization of compilers which evaluates constant expressions already at compile time. Constant folding is valid only if the results computed by the compiler are exactly the same as the results which would be computed at run-time by the target machine arithmetic. We classify different arithmetics by deriving a general condition under which a target-machine arithmetic can be replaced by a compiler arithmetic. Furthermore, we consider integer arithmetics as a special case. They can be described by residue class arithmetics. We show that these arithmetics form a lattice. Using the order relation in this lattice, we establish a necessary and sufficient criterion under which constant folding can be done in a residue class arithmetic that is different from the one of the target machine. Concerning formal verification, we have formalized our proofs in the Isabelle/HOL system. As examples, we discuss the Java and C integer arithmetics and show which compiler arithmetics are valid for constant folding. This discussion reveals also potential sources of incorrect behavior of C compilers. 相似文献
198.
199.
Hassan Elhadidy Jan Franc Eduard Belas Pavel Hlídek Pavel Moravec Roman Grill Pavel Hoschl 《Journal of Electronic Materials》2008,37(9):1219-1224
Thermoelectric effect spectroscopy and photoluminescence techniques were used to study the defect levels in samples from three
crystals of CdTe:In grown by the vertical gradient freeze method. The main goal of the investigation was to study defects,
which strongly trap charge carriers or act as recombination centers in order to eliminate them from the technological process.
The main difference among detecting and non-detecting samples was the absence of electron traps with a very high capture cross-section
and energy 0.6 eV to 0.7 eV, which act as lifetime killers even at low concentrations. Recently published ab initio calculations show a complex of Te antisite and Cd vacancy within this energy range. 相似文献
200.
Luiz A. Canalle Sander S. van Berkel Laurens T. de Haan Jan C. M. van Hest 《Advanced functional materials》2009,19(21):3464-3470
The copper‐catalyzed azide–alkyne 1,3‐dipolar cycloaddition (CuAAC) is extensively used for the functionalization of well‐defined polymeric materials. However, the necessity for copper, which is inherently toxic, limits the potential applications of these materials in the area of biology and biomedicine. Therefore, the first entirely copper‐free procedure for the synthesis of clickable coatings for the immobilization of functional molecules is reported. In the first step, azide‐functional coatings are prepared by thermal crosslinking of side‐chain azide‐functional polymers and dialkyne linkers. In a second step, three copper‐free click reactions (i.e., the Staudinger ligation, the dibenzocyclooctyne‐based strain‐promoted azide–alkyne [3+2] cycloaddition, and the methyl‐oxanorbornadiene‐based tandem cycloaddition?retro‐Diels?Alder (crDA) reaction) are used to functionalize the azide‐containing surfaces with fluorescent probes, allowing qualitative comparison with the traditional CuAAC. 相似文献