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1.
Multi-projector displays allow the realization of large and immersive projection environments by allowing the tiling of projections from multiple projectors. Such tiled displays require real time geometrical warping of the content that is being projected from each projector. This geometrical warping is a computationally intensive operation and is typically applied using high-end graphics processing units (GPUs) that are able to process a defined number of projector channels. Furthermore, this limits the applicability of such multi-projector display systems only to the content that is being generated using desktop based systems. In this paper we propose a platform independent FPGA based scalable hardware architecture for geometric correction of projected content that allows addition of each projector channel at a fractional increase in logic area. The proposed scheme provides real time correction of HD quality video streams and thus enables the use of this technology for embedded and standalone devices.  相似文献   
2.
Fine-grained fully-lamellar (FL) microstructure is desired for TiAl components to serve as compressor/turbine blades and turbocharger turbine wheels. This study deals with the process and phase transformation to produce FL microstructure for Mo stabilized beta-gamma TiAl alloys without single α-phase field. Unlike the α + γ two-phased TiAl or beta-gamma TiAl with single α-phase field, the wrought multi-phase TiAl–4/6Nb–2Mo–B/Y alloys exhibit special annealing process to obtain FL microstructure. Short-term annealing at temperatures slightly above β-transus is recommended to produce the desired FL microstructure. The related mechanism is to guarantee the sufficient diffusion homogenization of β stabilizers during single β-phase annealing, and further avoid α decomposition by α → γ + β when cooling through α + β + γ phase field. The colony boundary β phase contributes to fine-grained nearly FL microstructure, by retarding the coarsening of the α phase grains.  相似文献   
3.
Numerical dissipation acts as artificial viscosity to make smoke viscous. Reducing numerical dissipation is able to recover visual details smeared out by the numerical dissipation. Great efforts have been devoted to suppress the numerical dissipation in smoke simulation in the past few years. In this paper we investigate methods of combating the numerical dissipation. We describe visual consequences of the numerical dissipation and explore sources that introduce the numerical dissipation into course of smoke simulation. Methods are investigated from various aspects including grid variation, high-order advection, sub-grid compensation, invariant conservation, and particle-based improvement, followed by discussion and comparison in terms of visual quality, computational overhead, ease of implementation, adaptivity, and scalability, which leads to their different applicability to various application scenarios.  相似文献   
4.
用于高频谐振器的PbTiO_3基压电陶瓷   总被引:1,自引:1,他引:0  
传统的PZT压电陶瓷的相对介电常数较大,一般为1 000以上,用于高频谐振器不易与线路匹配;而PbTiO3基压电陶瓷的相对介电常数较小,一般仅为200左右,对于10 MHz以上频率的谐振器,用PbTiO3基压电陶瓷作为压电振子是最佳的选择。本文主要研究用于高频谐振器的MnO2和Nd2O3改性PbTiO3基压电陶瓷的性质。PbTiO3基压电陶瓷的性质的改善是与此种陶瓷的制备工艺,显微结构和电导机制紧密相关的。  相似文献   
5.
激光熔覆Ni基SiC合金涂层组织与性能的研究   总被引:5,自引:0,他引:5  
利用5kWCO2连续波激光器在16Mn钢基材表面对含20%(体积比)SiC陶瓷粉末的镍基自熔性合金粉末进行激光熔覆得到Ni基SiC合金涂层(NiSiC)。研究了合金涂层的组织形貌及相结构,并用单纯的镍基合金涂层(Ni60)进行了显微硬度及滑动磨损性能的对比试验。结果表明,NiSiC合金涂层由γ枝晶及其间的共晶组织组成,主要组成相为γ-Ni,γ-(Ni,Fe)固溶体和(Cr,Fe)7C3,Cr23C6及(Cr,Si)3Ni3Si等化合物。添加SiC的镍基合金涂层NiSiC比单纯的镍基合金涂层Ni60具有较高的硬度和耐磨性。  相似文献   
6.
Significant increases in the activity of vanadium(III) amidinate catalysts for ethylene polymerization have been obtained by immobilization on a MgCl2‐based support prepared by reaction of AlEt3 with a MgCl2/ethanol adduct. Catalyst immobilization and activation on this type of support prevents the rapid decay in activity observed under homogeneous polymerization conditions with unsupported catalysts. Stable polymerization activity is also observed with analogous titanium(III) complexes. Polyethylene with narrow molecular weight distribution and spherical particle morphology is obtained without reactor fouling. Copyright © 2005 Society of Chemical Industry  相似文献   
7.
抗窄带干扰宽带中频数字接收机的设计与实现   总被引:3,自引:0,他引:3  
讨论了存在强干扰条件下MSK中频数字接收机的频域窄带干扰抑制、伪码快速捕获、MSK相干解调等实现方法。具体实现中提出了基于功率估计的码捕获门限实时调整方案,解决了动态干扰条件下的快速码捕获问题。基于FPGA DSP硬件设计和软件可编程数字信号处理算法,接收机具有较强的适应性和稳定性。  相似文献   
8.
Comments on the article "A house divided? The psychology of red and blue America" by D. C. Seyle and M. L. Newman (see record 2006-11202-001). Seyle and Newman concluded that the red and blue metaphor is inaccurate and proposed a purple America strategy to better convey that the majority of people do not align themselves with political extremes. There is interdisciplinary agreement on this. Although not cited by Seyle and Newman, the findings by Professor Fiorina of Stanford University were reported by the APA Monitor on Psychology in its coverage of the 2005 APA State Leadership Conference (Murray Law, 2005). In contrast to their social psychological analysis, Seyle and Newman were incorrect in concluding that "[a]s psychologists, we are not in a position to change either the elements of the American political system that may spur this conflict or even the decisions made by pundits, politicians, and reporters about the terms they choose to use in political discussion" (p. 579). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The vicissitudes of the Israeli-Palestinian peace process since 1967 are analyzed using attitudes and related concepts where relevant. The 1967 war returned the two peoples' zero-sum conflict around national identity to its origin as a conflict within the land both peoples claim. Gradually, new attitudes evolved regarding the necessity and possibility of negotiations toward a two-state solution based on mutual recognition, which became the building stones of the 1993 Oslo agreement. Lacking a commitment to a final outcome, the Oslo-based peace process was hampered by reserve options, which increased avoidance at the expense of approach tendencies as the parties moved toward a final agreement. The resulting breakdown of the process in 2000 produced clashing narratives, reflecting different anchors for judgment and classical mirror images. Public support for violence increased, even as public opinion continued to favor a negotiated two-state solution. Reviving the peace process requires mutual reassurance about the availability of a partner for negotiating a principled peace based on a historic compromise that meets the basic needs and validates the identities of both peoples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Responds to the comments by L. T. Hoshmand (see record 2003-08988-012) and J. Aros (see record 2003-08988-013) on the article by J. Arnett (see record 2002-18352-003) regarding the psychology of globalization. In this response, Arnett discusses the moral implications of globalization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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