引入智能虚拟讲解员的云展厅构建与交互反馈研究

奥林匹克遗产是全人类的宝贵财富,利用科技与文化艺术相融合,对实现北京冬奥会及奥林匹克遗产和精神文化的多元呈现和高效传播至关重要.线上云展厅作为信息时代数字博物馆发展的重要趋势,虽然在单项数字博物馆与交互系统技术研究方面已具备较好的基础,但尚未形成体系化、智能化、交互友好的冬奥会奥林匹克数字博物馆系统.面向北京2022年冬季奥林匹克运动会,提出一种具有交互反馈的云展厅系统构建方式,通过构建具有虚拟讲解员的智能交互云展厅,进一步探索交互反馈在知识传播型的数字博物馆中对于非物质文化遗产的传播作用.为了探索视听交互反馈对云展厅的奥林匹克精神文化传播的影响,同时提升知识传播型云展厅中的用户体验,对32名参与者进行用户实验.研究结果表明,所构建的云展厅能够极大地促进奥林匹克文化与精神的传播;同时,在云展厅中引入视听交互反馈能够提高用户的感知控制,从而有效地提升用户体验.     

An anion-directed unprecedent three-dimensional array with erbium(III) based on the 2,6-pyridinedicarboxylate

Reaction of 2,6-pyridine-dicarboxylic acid and ammonium oxalate with erbium salt results in the formation of a self-assembly network based upon mixed ligands of oxalate and pyridine-dicarboxylate formulated as {[Er₄(pydc)₂(μ₄-C₂O₄)₄]·8H₂O·6H₂O}_n (H₂pydc = 2,6-pyridine-dicarboxylic acid), in which supramolecular left-handed and right-handed helices are connected via μ₄-oxalate anions, and gave the 1D coordination channels constructed via bridging oxalate and pydc ligands. The complex also displayed photo-luminescent properties in the solid state at room temperature.     

Stability analysis for fractional-order neural networks with time-varying delay

This paper focuses on the stability analysis for fractional-order neural networks with time-varying delay. A novel Lyapunov's asymptotic stability determination theorem is proved, which can be used for fractional-order systems directly. Different from the classical Lyapunov stability theorem, constraint condition on the derivative of Lyapunov function is revised as an uniformly continuous class-K function in the fractional-order case. Based on this novel Lyapunov stability theorem and free weight matrix method, a new sufficient condition on Lyapunov asymptotic stability of fractional-order Hopfield neural networks is derived by constructing a suitable Lyapunov function. Moreover, two numerical examples are provided to illustrate the effectiveness of these criteria.     

SnO2:F沉积的La0.67Sr0.33MnO3薄膜的电阻开关特性研究

采用脉冲激光沉积技术在SnO2:F(FTO)衬底上制备了La0.67 Sr0.33 MnO3( LSMO)薄膜.室温下利用直流电压对Au/LSMO/FTO三明治结构的器件进行了电化学测试.结果显示样品具有明显的双极性电阻开关性能.通过对I-V特性曲线进行分析,认为在高阻态时肖特基势垒和空间电荷限制电流输运机制调控.在高场区,电阻开关的高低阻态现象由电子陷阱中心分布的不对称引起的空间电荷限制电流理论来解释.     

艾粉提取物及其复合保鲜剂对圣女果番茄和葡萄的保鲜效果研究

目的研究艾粉提取物及其复合保鲜剂对圣女果番茄和葡萄的保鲜效果。方法首先以圣女果番茄为研究对象,以果实失重量、感官评价为指标,探讨艾粉不同溶剂提取物的保鲜效果。随后以葡萄为研究对象,以果实腐烂率、硬度、pH值等为指标,筛选出艾粉提取物与白及、葛根等复配后的最优保鲜剂配方。最后采用高效液相色谱法,对艾粉不同提取物进行分析和比较,初步判定和鉴别提取物中的保鲜效果成分。结果对于圣女果番茄,艾粉100%乙醇提取物和乙酸乙酯提取物相对于水提物和50%(V/V)乙醇提取物具有更好的保鲜效果;以艾粉100%乙醇提取物为主要成分,白及鲜液和葛根粉为成膜剂,少量乙醇为助溶剂的复合保鲜剂对葡萄具有最佳的保鲜效果;100%乙醇提取物和乙酸乙酯提取物均具有较高含量的棕矢车菊素和异泽兰黄素,50%乙醇提取物其次,水提物最低,此两种成分含量高低与保鲜效果强弱结果一致。结论艾粉乙醇提取物具有良好的保鲜作用,具有开发安全无毒的植物源保鲜剂的应用前景。     

一种基于DES和RSA的数字签名方案

本文分析DES加密算法和RSA签名算法。作者采用DES算法和RSA算法相结合的密码方案,引用摘要,提出了一种基于DES和RSA的新的数字签名方案,并给出了它的应用实例。     

Global exponential stability of bidirectional associative memory neural networks with time delays.

In this paper, we consider delayed bidirectional associative memory (BAM) neural networks (NNs) with Lipschitz continuous activation functions. By applying Young's inequality and Hoelder's inequality techniques together with the properties of monotonic continuous functions, global exponential stability criteria are established for BAM NNs with time delays. This is done through the use of a new Lyapunov functional and an M-matrix. The results obtained in this paper extend and improve previous results.     

Robust stability analysis for uncertain recurrent neural networks with leakage delay based on delay-partitioning approach

This paper focuses on the issue of robust stability analysis for recurrent neural networks (RNNs) with leakage delay. By constructing a novel Lyapunov–Krasovskii functional together with the reciprocally convex approach and the free-weighting matrix technique, some less conservative stability criteria in terms of linear matrix inequalities for RNNs are derived. The new contribution of this paper is that a novel delay-partitioning method is proposed, and some new zero equalities are introduced. Finally, several examples are given to demonstrate the effectiveness of the proposed methods. The simulated results reveal that the leakage delay has great influence on the dynamical systems, and it cannot be neglected.