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O. Jedrkiewicz R. Loudon J. Jeffers 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,39(1):129-140
Previous work on the retrodictive theory of direct
detection is extended to cover the homodyne detection of coherent optical
signal states
and
. The retrodictive input state probabilities are obtained by
the application of Bayes' theorem to the corresponding predictive
distributions, based on the probability operator measure (POM) elements for
the homodyne process. Results are derived for the retrodictive information
on the complex amplitude of the signal field obtainable from the difference
photocount statistics of both 4-port and 8-port balanced homodyne detection
schemes. The local oscillator is usually assumed much stronger than the
signal but the case of equal strengths in 4-port detection is also
considered. The calculated probability distributions and error rates are
illustrated numerically for values of signal and local oscillator strengths
that extend from the classical to the quantum regimes. 相似文献
874.
This study investigated the room-temperature compression molding/particle leaching approach to fabricate three-dimensional porous scaffolds for tissue engineering. Scaffolds with anatomical shapes (ear, joint, tube, cylinder) were made from biodegradable poly(D,L-lactide) and poly[(D,L-lactide)-co-glycolide]. The utility of this room-temperature compression approach comes from the effect of solvent assistance, but the tendency for post-molding scaffold shrinkage is a problem unique to this method and is thus examined with emphasis in this paper. Scaffold shrinkage was found to be tolerable under normal fabrication conditions with high salt contents, which is just what the preparation of highly porous scaffolds requires. Furthermore, the resultant porosities after salt leaching were measured as well as the initial scaffold shrinkages after solvent evaporation, and the relation between them was revealed by theoretical analysis and confirmed by comparison with experimental measurements. The pores were interconnected, and porosity can exceed 90%. The effects of porosity on the mechanical properties of porous scaffolds were also investigated. This convenient fabrication approach is a prospective method for the tailoring of porous scaffolds for a variety of possible applications in tissue engineering and tissue reconstruction. 相似文献
875.
一般化两人零和模糊对策的模糊规划法 总被引:1,自引:0,他引:1
本文在充分考虑局中人的策略集是模糊子集的基础上,给出更一般化的具有模糊支付与模糊赢得的两人零和模糊对策的模糊规划模型。利用模糊数的序方法,得到了此对策求解问题可以转化为带有模糊参数的两个经典规划的求解问题。文末给出算例予以说明。 相似文献
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在许多桥梁工程中,锚碇岩石边坡的承载力和稳定性对整个桥梁工程的稳定和正常运营起着至关重要的作用.利用推广的非等间距灰色预测理论模拟了虎门大桥锚碇隧洞拉拔力试验中拉拔力与相应山体位移间的关系,并用所得到的非等距灰色预测模型预测了山体位移,结果表明,非等间距灰色预测模型的预测精度令人满意.研究结果对桥梁工程安全施工和岩石工程预测预报有重要理论意义和工程价值. 相似文献
878.
Mei‐Ling Feng Dr. Wei‐Wei Xiong Dong Ye Jian‐Rong Li Xiao‐Ying Huang Prof. Dr. 《化学:亚洲杂志》2010,5(8):1817-1823
A series of novel organically templated germanium antimony sulfides have been solvothermally synthesized and structurally, thermally, and optically characterized. The compound [Me2NH2]6[(Ge2Sb2S7)(Ge4S10)] ( 1 ) features two distinct tetranuclear [Ge2Sb2S7]2? and [Ge4S10]4? isolated clusters. The compound [(Me)2NH2][DabcoH]2[Ge2Sb3S10] ( 2 ) (Dabco=triethylenediamine) features a 1D‐[Ge2Sb3S10]n3n? ribbon constructed with two [GeSbS5]n3n? chains bridged by Sb3+ ion in ψ‐SbS4 configuration. Compounds [M(en)3][GeSb2S6] (M=Ni ( 3 ), Co ( 4 ) en=ethylenediamine) feature the unique 2D grid layer structures of [GeSb2S6]n2n?. The compound [(Me)2NH2]2[GeSb2S6] ( 5 ) previously reported by us features a 3D chiral microporous structure with the chiral channels. The optical absorption spectra indicate that all the compounds are wide bandgap semiconductors. Thermal stabilities of these compounds have been investigated by thermogravimetric analyses (TGA). 相似文献
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