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101.
本文介绍如何在兼容ARMV4指令集的32位超高速RISC处理器(FA626)所构建的SoC平台上(即FIE8180),运用智原科技所提供的FA626-Linux开发包通过armboot装载Linux2.6操作系统。使开发人员可以在基于FIE8180 SoC的仿真平台-MediaCreative!上进行二次开发和验证设计。 相似文献
102.
Zdenka Rie?anová 《Information Sciences》2009,179(5):529-534
We prove that in every pseudocomplemented atomic lattice effect algebra the subset of all pseudocomplements is a Boolean algebra including the set of sharp elements as a subalgebra. As an application, we show families of effect algebras for which the existence of a pseudocomplementation implies the existence of states. These states can be obtained by smearing of states existing on the Boolean algebra of sharp elements. 相似文献
103.
The contribution of this paper is twofold. First, we exploit copula methodology, with two threshold GARCH models as marginals, to construct a bivariate copula-threshold-GARCH model, simultaneously capturing asymmetric nonlinear behaviour in univariate stock returns of spot and futures markets and bivariate dependency, in a flexible manner. Two elliptical copulas (Gaussian and Student's-t) and three Archimedean copulas (Clayton, Gumbel and the Mixture of Clayton and Gumbel) are utilized. Second, we employ the presenting models to investigate the hedging performance for five East Asian spot and futures stock markets: Hong Kong, Japan, Korea, Singapore and Taiwan. Compared with conventional hedging strategies, including Engle's dynamic conditional correlation GARCH model, the results show that hedge ratios constructed by a Gaussian or Mixture copula are the best-performed in variance reduction for all markets except Japan and Singapore, and provide close to the best returns on a hedging portfolio over the sample period. 相似文献
104.
In this paper, we consider the coefficient-based regularized least-squares regression problem with the lq-regularizer (1≤q≤2) and data dependent hypothesis spaces. Algorithms in data dependent hypothesis spaces perform well with the property of flexibility. We conduct a unified error analysis by a stepping stone technique. An empirical covering number technique is also employed in our study to improve sample error. Comparing with existing results, we make a few improvements: First, we obtain a significantly sharper learning rate that can be arbitrarily close to O(m−1) under reasonable conditions, which is regarded as the best learning rate in learning theory. Second, our results cover the case q=1, which is novel. Finally, our results hold under very general conditions. 相似文献
105.
New applications of clique separator decomposition for the Maximum Weight Stable Set problem 总被引:1,自引:0,他引:1
Graph decompositions such as decomposition by clique separators and modular decomposition are of crucial importance for designing efficient graph algorithms. Clique separators in graphs were used by Tarjan as a divide-and-conquer approach for solving various problems such as the Maximum Weight Stable Set (MWS) problem, Colouring and Minimum Fill-in. The basic tool is a decomposition tree of the graph whose leaves have no clique separator (so-called atoms), and the problem can be solved efficiently on the graph if it is efficiently solvable on its atoms. We give new examples where the clique separator decomposition works well for the MWS problem; our results improve and extend various recently published results. In particular, we describe the atom structure for some new classes of graphs whose atoms are P5-free (the P5 is the induced path with five vertices) and obtain new polynomial time results for the MWS problem. The complexity of this problem on the class of P5-free graphs is still unknown. 相似文献
106.
采用单辊快淬法制备了Fe81Zr7Nb2B10和Fe78Co2.5Zr7Nb2B10Cu0.5非晶合金,在不同温度下对两种合金进行了热处理。利用差热分析仪(DTA)、X射线衍射仪(XRD)和振动样品磁强计(VSM)等仪器对两种合金的热性能、微观结构和磁性能进行了测试分析。结果表明在Fe78Co2.5Zr7Nb2B10Cu0.5合金的晶化过程中存在预结晶效应,而在Fe81Zr7Nb2B10合金的晶化过程中没有。Fe81Zr7Nb2B10和Fe78Co2.5Zr7Nb2B10Cu0.5合金经803 K退火后,分别有α-Fe和α-Fe(Co)相从非晶基体中析出。随退火温度的升高,两种合金的比饱和磁化强度(Ms)变化趋势相似,但矫顽力(Hc)变化趋势明显不同。 相似文献
107.
采用磁控溅射的方法制备了Ta/NiFe/Ta磁电阻薄膜,分别将CoFe-NOL和Al2O3插层引入NiFe薄膜,研究纳米氧化层(NOL)对NiFe薄膜性能的影响。实验结果表明:将CoFe-NOL引入NiFe薄膜,CoFe-NOL对NiFe薄膜性能有重要影响,并且CoFe-NOL在薄膜中的位置不同影响效果也不同;CoFe-NOL处于Ta/NiFe界面时,由于破坏了NiFe薄膜的织构,导致了NiFe薄膜的各向异性磁电阻(AMR)值的减小和矫顽力的上升;CoFe-NOL处于NiFe/Ta界面时,则不会破坏NiFe薄膜的织构,其AMR值和矫顽力基本没有变化。将Al2O3插层引入NiFe薄膜,由于Al2O3插层的"镜面反射"作用,合适厚度的Al2O3插层可以改善薄膜的微结构,提高薄膜的磁电阻值,改善薄膜的磁性能。当Al2O3插层厚度为1.5 nm时,NiFe薄膜有最佳的微结构和性能。 相似文献
108.
In this paper, two-step extended Runge–Kutta–Nyström-type methods for the numerical integration of perturbed oscillators are presented and studied. The new methods inherit the framework of two-step hybrid methods and are adapted to the special feature of the true flows in both the internal stages and the updates. Based on the EN-trees theory [H.L. Yang, X.Y. Wu, X. You, Y.L. Fang, Extended RKN-type methods for numerical integration of perturbed oscillators, Comput. Phys. Comm. 180 (2009) 1777–1794], order conditions for the new methods are derived via the BBT-series defined on the set BT of branches and the BBWT-series defined on the subset BWT of BT. The stability and phase properties are analyzed. Numerical experiments show the applicability and efficiency of our new methods in comparison with the well-known high quality methods proposed in the scientific literature. 相似文献
109.
Patrizia Di Bello 《History of Photography》2013,37(4):412-420
This article focuses on the photographs of sculptures, in particular Raffaelle Monti’s veiled figures, taken by the London Stereoscopic and Photographic Company at the 1862 International Exhibition, to explore the relationship between vision and touch in the appeal of stereographs. Their apparent simplicity as reproductions of works of art belies a rich formal and conceptual complexity that attends to many of the issues raised by the Exhibition and its critics, at the time and since. The appeal of stereographs of sculptures can be conceptualised in the consonance between sculpture and photography as media that relied on mechanical production and reproduction, making the shift from sculpture to stereo one of different iterations rather than translation from one medium to another – both relied on the disavowal of the anonymous, mechanical labour that went into making them. 相似文献
110.
Monte Carlo simulations of gas, coal and nuclear plant investment returns are used as inputs of a Mean–Variance Portfolio optimization to identify optimal base load generation portfolios for large electricity generators in liberalized electricity markets. We study the impact of fuel, electricity, and CO2 price risks and their degree of correlation on optimal plant portfolios. High degrees of correlation between gas and electricity prices – as observed in most European markets – reduce gas plant risks and make portfolios dominated by gas plant more attractive. Long-term power purchase contracts and/or a lower cost of capital can rebalance optimal portfolios towards more diversified portfolios with larger shares of nuclear and coal plants. 相似文献