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Time optimal quantum control of two-qubit systems

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2116-2121页

作者： LI Bin YU ZuHuan fei shaoming LI-JOST XianQing School of Mathematical Sciences Capital Normal University School of Mathematics and Statistics Northeast Normal University Max-Planck-Institute for Mathematics in the Sciences

We study the optimal quantum control of heteronuclear two-qubit systems described by a Hamiltonian containing both nonlocal internal drift and local control *** derive an explicit formula to compute the minimum time required to steer the system from an initial state to a specified final *** applications the minimal time to implement Controlled-NOT gate,SWAP gate and Controlled-U gate is calculated in *** experimental realizations of these quantum gates are explicitly presented.

关键词： time optimal quantum control heteronuclear two-spin system local invariants

Characterization of four-qubit states via Bell inequalities

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Chinese Science Bulletin 2013年第19期58卷 2334-2339页

作者： ZHAO Hui ZHANG XingHua fei shaoming WANG ZhiXi College of Applied Sciences Beijing University of Technology School of Mathematical Sciences Capital Normal University

A set of Bell inequalities classifying the quantum entanglement of four-qubit states is presented. These inequalities involve only two measurement settings per observer and can characterize fully separable, bi-separable and tri-separable quantum states. In addition, a quadratic inequality of the Bell operators for four-qubit systems is derived.

关键词：贝尔不等式表征二次不等式量子纠缠量子比特分离量子态运营商

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玻色弦的BKS核和路径积分

高能物理与核物理 1989年第4期13卷 334-338页

作者：费少明虞跃浙江大学中国高等科学技术中心(世界实验室)理论物理分中心中国科学院高能物理研究所

本文利用Blattner-Kostant-Sternberg(BKS)核讨论了玻色弦的几何量子化和路径积分量子化的联系,给出了Polyakov路径积分表达式.

关键词：玻色弦 BKS核路径积分原子核

An Approximate Maximum Likelihood Algorithm for Target Localization in Multistatic Passive Radar

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Chinese Journal of Electronics 2019年第1期28卷 195-201页

作者： WANG Jun QIN Zhaotao GAO fei WEI shaoming School of Electronics and Information Engineering Beihang University

This paper addresses the problem of target localization using Bistatic range(BR) measurements in a distributed multistatic passive radar system. The rangebased positioning technique employs multiple transmitterreceiver pairs, which provide separate BR *** on the Maximum likelihood(ML) function,an efficient algebraic Approximate maximum likelihood(AML) algorithm for single target localization is *** closed-form AML solution has neither initial condition requirements nor convergence difficulty. Simulations are included to compare its performance to that of the CramerRao lower bound(CRLB) and the Two-step Weighted least squares(TS-WLS) algorithm. The proposed method is shown to be able to achieve the CRLB accuracy under Gaussian measurement noise. It is more robust to noise than the TS-WLS method, and presents relative insensitivity to target-sensor geometry.

关键词： Bistatic range(BR) measurement Multistatic passive radar Target localization Approximate maximum likelihood(AML) algorithm Maximum likelihood(ML) function

Swarm intention identification via dynamic distribution probability image

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Chinese Journal of Aeronautics 2024年第10期37卷 380-392页

作者： Yinhan WANG Jiang WANG shaoming HE fei WANG Qi WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China

In the realm of decision-making for defense and security applications,it is paramount to swiftly and accurately identify the intentions of incoming *** identification methods predominantly focus on single-target applications and overlook the perturbations introduced by measurement *** this study,we propose a novel concept:the Dynamic Distribution Probability(DDP)image,which is constructed using the estimated state and its covariance *** grayscale pixel value within the image signifies the probability of the presence of the agent within the *** proposed identification scheme integrates the use of Extended Kalman Filter(EKF),Convolutional Neural Network(CNN),Back Propagation(BP)network,and Gated Recurrent Unit(GRU)***,the DDP image is processed through a CNN to distill the formation characteristics,and the estimated swarm state from EKF is inputted into a BP network to deduce the kinematic *** outputs from both networks are summed and subsequently channeled into a GRU network to capture temporal *** numerical simulations and flight experiments are presented to demonstrate the robust anti-noise capability of the proposed scheme compared with conventional methods,as well as its superior training efficiency.

关键词： Intention Identification Kalman filters Convolutional neural networks Swarm intelligence

Correlat ion of thiamine metabolite levels with cognitive function in the non-demented elderly

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Neuroscience Bulletin 2015年第6期31卷 676-684页

作者： Jingwen Lu Xiaoli Pan Guoqiang fei Changpeng Wang Lei Zhao shaoming Sang Huimin Liu Meng Liu Hui Wang Zhiliang Wang Chunjiu Zhong Department of Neurology Zhongshan Hospital and Shanghai Medical CollegeFudan University State Key Laboratory of Medical Neurobiology and Institutes of Brain Science Fudan University Regional Health Service Center of Xujiahui

Thiamine metabolism is critical for glucose metabolism and also vital for brain function, which is susceptible to decline in the elderly. This study aimed to investigate whether thiamine metabolites correlate with cognitive function in the non-demented elderly and their impact factors. Volunteers 〉60 years old were recruited and their blood thiamine metabolites and Mini-Mental State Examination （MMSE） scores were measured. The apolipoprotein E （APOE） genotype, routine blood parameters, liver and kidney function, and levels of fasting blood glucose and triglycerides were also measured. The results showed that the thiamine diphosphate （TDP） level weakly correlated with MMSE score in the non-demented elderly. Participants with high TDP levels performed better in Recall and Attention and Calculation than those with low TDP. TDP levels were associated with the APOE E2 allele, body mass index, hemoglobin level, fasting blood glucose, and triglycerides. Our results suggest that TDP, which is easily affected by many factors, impacts cognitive function in the elderly.

关键词： thiamine diphosphate cognitive function non-demented elderly

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三车道公路隧道照明灯具布置参数研究

地下空间与工程学报 2017年第S1期13卷 471-475页

作者：吴绍明吴梦军马非王乾广州市高速公路有限公司广州510288 招商局重庆交通科研设计院有限公司重庆400067 重庆交通大学交通运输学院重庆400074

随着公路隧道数量和里程的增加,隧道运营过程中的照明将会消耗更巨大的电能,这是运营单位所承担的主要负担,如何有效的降低该能耗已经成为重要的问题。国内外专家学者对此作了大量研究,通常使照明灯具达到最好的照明效果是降低电能消耗... 详细信息

随着公路隧道数量和里程的增加,隧道运营过程中的照明将会消耗更巨大的电能,这是运营单位所承担的主要负担,如何有效的降低该能耗已经成为重要的问题。国内外专家学者对此作了大量研究,通常使照明灯具达到最好的照明效果是降低电能消耗的有效途径之一。采用DIALux照明仿真软件,分别建立隧道照明灯具两侧对称布置和交错布置模型,以洞内路面亮度、照度和均匀度满足交通安全要求为约束条件,分析了不同布灯形式和灯具不同照射角度情况对隧道内照明环境的影响,通过综合分析比较,得出当灯具交错布置、发光轴线与竖直面夹角为15°时的照明环境最好。

关键词：隧道照明布灯方式照明效果参数优化

不同桉树混交林土壤理化性质、酚酸含量与酶活性的差异

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西北农林科技大学学报（自然科学版） 2022年第12期50卷 54-63,76页

作者：罗华龙刘文祥杨梅叶绍明程飞广西大学林学院广西南宁530004 广西国有七坡林场广西南宁530225

【目的】研究桉树与不同阔叶树种混交对土壤理化性质、酚酸含量和酶活性的影响,分析酚酸物质与酶活性的关系,为改善桉树纯林的土壤质量、合理经营桉树人工林及适宜混交树种的选择提供参考。【方法】在广西凭祥市选择6年生桉树纯林以及... 详细信息

【目的】研究桉树与不同阔叶树种混交对土壤理化性质、酚酸含量和酶活性的影响,分析酚酸物质与酶活性的关系,为改善桉树纯林的土壤质量、合理经营桉树人工林及适宜混交树种的选择提供参考。【方法】在广西凭祥市选择6年生桉树纯林以及桉树与豆科树种(降香黄檀、格木)、非豆科树种(红锥)的混交林作为研究对象,测定不同林分类型桉树根际与非根际土壤的理化性质(铵态氮、有机碳、全氮、硝态氮含量、pH、自然含水率)、酚酸类物质含量及酶(多酚氧化酶、脲酶、蔗糖酶、过氧化氢酶、蛋白酶)活性,并采用相关性和冗余分析方法揭示酚酸含量和酶活性的相关关系。【结果】(1)桉树混交林根际与非根际土壤的pH、自然含水率、有机碳、全氮、硝态氮、铵态氮含量均总体高于桉树纯林。(2)与桉树纯林相比,混交林桉树根际土壤酚酸物质含量升高,表现为桉树×红锥混交林(50.01μg/g)>桉树×格木混交林(38.39μg/g)>桉树×降香黄檀混交林(36.94μg/g)>桉树纯林(27.76μg/g);非根际土壤的酚酸类物质含量降低,表现为桉树纯林(21.45μg/g)>桉树×降香黄檀混交林(16.35μg/g)>桉树×格木混交林(15.50μg/g)>桉树×红锥混交林(13.52μg/g)。(3)桉树混交林根际与非根际土壤的蛋白酶、蔗糖酶、脲酶和过氧化氢酶活性均高于桉树纯林;桉树混交林根际土壤的多酚氧化酶活性总体低于纯林,而非根际土壤的多酚氧化酶活性显著高于纯林。(4)相关性和冗余分析结果表明,土壤酚酸类物质含量与酶活性具有较高的相关性,阿魏酸、对羟基苯甲酸、香草酸含量在一定程度上能够解释根际与非根际土壤间酶活性的差异。【结论】混交造林对桉树根际与非根际土壤理化性质、酚酸类物质含量和酶活性影响显著,能够增加桉树根际土壤酚酸积累,减缓非根际土壤酚酸富集,提高土壤养分和酶活性,其中红锥与桉树混交更有利于维持土壤肥力。

关键词：桉树混交林土壤酚酸类物质土壤酶活性土壤理化性质

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多模式电子锁控制器设计

内江师范学院学报 2020年第2期35卷 47-51页

作者：江绍明方飞内江师范学院物理与电子信息工程学院四川内江641100 内江师范学院智能制造创新中心四川内江641100

传统机械锁具及密码锁具逐渐被更安全便捷的指纹、虹膜识别电子锁具所代替,但是任何单一的电子锁都存在较大的风险。提出了一种多模式认证的电子锁控制系统,介绍了指纹识别工作原理及算法,结合实际产品中的需求,设计系统总体框图及硬件... 详细信息

传统机械锁具及密码锁具逐渐被更安全便捷的指纹、虹膜识别电子锁具所代替,但是任何单一的电子锁都存在较大的风险。提出了一种多模式认证的电子锁控制系统,介绍了指纹识别工作原理及算法,结合实际产品中的需求,设计系统总体框图及硬件电路,采用STM32F401作为微处理器,FPS200作为指纹图像传感器.重点分析了软件系统的工作流程以及指纹图像采集、指纹识别算法、密码认证等软件流程.通过设计系统软硬件综合测试,结果表明文中设计的指纹识别系统具有很高的指纹识别准确度.

关键词：指纹识别电子锁无线传输密码锁微控制器