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111.
Michal Kern Lorenzo Tesi David Neusser Nadine Rußegger Mario Winkler Alexander Allgaier Yannic M. Gross Stefan Bechler Hannes S. Funk Li-Te Chang Jörg Schulze Sabine Ludwigs Joris van Slageren 《Advanced functional materials》2021,31(7):2006882
Hybrid materials consisting of organic semiconductors and molecular quantum bits promise to provide a novel platform for quantum spintronic applications. However, investigations of such materials, elucidating both the electrical and quantum dynamical properties of the same material have never been reported. Here the preparation of hybrid materials consisting of conducting polymers and molecular quantum bits is reported. Organic field-effect transistor measurements demonstrate that the favorable electrical properties are preserved in the presence of the qubits. Chemical doping introduces charge carriers into the material, and variable-temperature charge transport measurements reveal the existence of mobile charge carriers at temperatures as low as 15 K. Importantly, quantum coherence of the qubit is shown to be preserved up to temperatures of at least 30 K, that is, in the presence of mobile charge carriers. These results pave the way for employing such hybrid materials in novel molecular quantum spintronic architectures. 相似文献
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114.
Wolfgang Bischoff 《Journal of multivariate analysis》2000,73(2):1017
Consider a general linear model Y=Xβ+Z where Cov Z may be known only partially. We investigate carefully the notions of sufficiency, ancillarity, invariance, and equivariance and related notions for projectors in a general linear model. In this way we can prove a Basu type theorem. This result can be used to give the relation between the sufficiency of the generalized least-squares estimator and the assumption that Z is normally distributed. So we can generalize the well-known result that the generalized least-squares estimator is sufficient for β if Z is normally distributed. Further we can solve the converse problem as well. 相似文献
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116.
Xianping Guo Onésimo Hernández-Lerma Tomás Prieto-Rumeau Xi-Ren Cao Junyu Zhang Qiying Hu Mark E. Lewis Ricardo Vélez 《TOP》2006,14(2):177-261
This paper is a survey of recent results on continuous-time Markov decision processes (MDPs) withunbounded transition rates, and reward rates that may beunbounded from above and from below. These results pertain to discounted and average reward optimality criteria, which are the most
commonly used criteria, and also to more selective concepts, such as bias optimality and sensitive discount criteria. For
concreteness, we consider only MDPs with a countable state space, but we indicate how the results can be extended to more
general MDPs or to Markov games.
Research partially supported by grants NSFC, DRFP and NCET.
Research partially supported by CONACyT (Mexico) Grant 45693-F. 相似文献
117.
On the Maximum Likelihood estimation of a linear structural relationship when the intercept is known
This paper considers the Maximum Likelihood (ML) estimation of the five parameters of a linear structural relationship y = α + βx when α is known. The parameters are β, the two variances of observation errors on x and y, the mean and variance of x. When the ML estimates of the parameters cannot be obtained by solving a simple simultaneous system of five equations, they are found by maximizing the likelihood function directly. Some asymptotic properties of the estimates are also obtained. 相似文献
118.
对基于算术编码的一个数据加密算法的已知明文攻击 总被引:3,自引:0,他引:3
指出文献[l]设计的数据加密算法在已知明文攻击下是不安全的,基于该加密算法的密文的高位比特对密钥的低位比特的不敏感性,可以利用分割攻击方法求出其全部密钥比特。 相似文献
119.
文章评论了PCB行业“三废”之一——‘废料’(PCB和CCL的生产过程中产生的)的治理——可资源化问题。PCB和CCL的边角料与废品等的新型物理回收及其综合利用,它可能是目前和今后实现PCB行业产品可再资源化和循环经济的最佳的方法之一。 相似文献
120.
对于多节点的协同网络,机会编码协同总是选择最佳中继参与协同,能够取得优越的中断概率性能。为了进一步提高中断概率性能,提出了基于冗余前置的机会编码协同中继策略,并对其在瑞利平坦慢衰落信道条件下的中断概率性能进行了计算机仿真。结果表明,所提策略的中断概率性能明显优于机会编码协同中继策略,若所要求的中断概率为10-3,当潜在协同中继数目为7,协同等级为0.5,目标信息速率为1 bit/s/Hz的条件下,所提策略较机会编码协同中继策略可以获得1.9 dB的信噪比增益。 相似文献