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基于混沌映射的图像加密硬件实现结构

华中科技大学学报（自然科学版） 2008年第6期36卷 84-88页

作者：张翌维沈绪榜郑新建张洵颖西安微电子技术研究所陕西西安710054

为了使图像加密硬件化和实用化,针对图像加密系统所需的置换、替代和扩散3种基本要素,提出了一种采用双RAM连接,加/解密过程多轮次、可复用的硬件实现结构.该实现结构通过地址产生器得到置换地址,与地址计数器配合完成像素的位置置换;... 详细信息

为了使图像加密硬件化和实用化,针对图像加密系统所需的置换、替代和扩散3种基本要素,提出了一种采用双RAM连接,加/解密过程多轮次、可复用的硬件实现结构.该实现结构通过地址产生器得到置换地址,与地址计数器配合完成像素的位置置换;通过灰度扩散与像素替代单元完成灰度的扩散与替代.验证中采用广义猫映射进行像素位置置换,将单向耦合映射格点用于像素的替代,并与灰度扩散相结合,两种混沌映射多轮次交替使用.分析和实验证明,该结构具有复用性好、吞吐率高且面积节约等特点.现场可编程门阵列验证表明,在200 MHz时钟频率下,进行4轮加/解密时的吞吐率分别达到4.17 Mbyte/s和3.85 Mbyte/s.

关键词：图像加密混沌映射分组密码现场可编程门阵列(FPGA) 猫映射灰度扩散

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软件定义卫星有效载荷技术研究

西北工业大学学报 2020年第S1期38卷 96-101页

作者：周渊张洵颖智永锋门永平西北工业大学陕西西安710072 西安空间无线电技术研究所陕西西安710100

随着计算机和电子信息技术的飞速发展,现代航天器有效载荷硬件平台计算和处理能力不断提升,有效载荷功能主要依赖于软件实现。目前航天器载荷的研制主要以硬件研制为主线,软件研制嵌入到硬件研制流程中,所有硬件和软件功能调试测试完成... 详细信息

随着计算机和电子信息技术的飞速发展,现代航天器有效载荷硬件平台计算和处理能力不断提升,有效载荷功能主要依赖于软件实现。目前航天器载荷的研制主要以硬件研制为主线,软件研制嵌入到硬件研制流程中,所有硬件和软件功能调试测试完成后才装星发射。这种研制方式研制周期长,且每种载荷产品软、硬件平台均不相同,硬件和软件复用率低,开发效率不高。为解决这些问题,提出了软件定义载荷的解决思路,统筹多种载荷功能需求,提出了软件定义高速数据传输、卫星测控、卫星通信、导航增强等多种载荷功能为一体的硬件架构和软件架构,支持在同一硬件平台上实现不同载荷功能在轨动态切换,实现载荷硬件批产化,载荷功能软件化,满足载荷设备快速集成和低成本要求。这种方法可有效克服传统卫星研制模式的不足,适用于深空探测领域任务和低成本短周期的微小卫星载荷制造领域。

关键词：卫星系统有效载荷软件定义实时操作系统模块化

基于YOLOv5的无人车自主目标识别优化算法

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兵工学报 2023年第9期44卷 2732-2744页

作者：赵晓冬张洵颖西北工业大学电子信息学院陕西西安710072

复杂地面战场环境下的自主目标识别是未来无人车实现智能化作战的关键技术。如何将基于深度学习的自主目标识别算法进行资源受限情况下的嵌入式计算平台部署应用,已成为目前无人车智能化赋能亟待解决的核心问题。以用于地面自主目标识别... 详细信息

复杂地面战场环境下的自主目标识别是未来无人车实现智能化作战的关键技术。如何将基于深度学习的自主目标识别算法进行资源受限情况下的嵌入式计算平台部署应用,已成为目前无人车智能化赋能亟待解决的核心问题。以用于地面自主目标识别的YOLOv5深度神经网络结构为基础,提出一种基于改进型注意力模块和BatchNorm层的多正则项自适应网络裁剪算法,在裁剪与训练的协同过程中实现网络结构的最优化裁剪;设计一种对权重实施不饱和映射以及对激活值实施饱和映射的组合式训练后INT8量化算法。将压缩优化后的YOLOv5x网络在基于Zynq UltraScale+MPSoC架构的嵌入式计算平台上进行应用部署及验证。验证结果表明:YOLOv5x网络在通道裁剪40%和INT8量化时,红外目标识别精度仅减少0.374%,可见光目标识别精度提升0.065%,目标识别帧频均可达到25帧/s,能够满足无人车复杂战场环境下自主目标识别的准确度及实时性要求;自主目标识别神经网络压缩优化算法可扩展应用于无人机、精确制导武器等其他作战平台。

关键词：无人车目标识别 YOLOv5x 正则化裁剪 INT8量化算法嵌入式平台

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TMR故障注入与验证方法研究与实现

计算机测量与控制 2014年第1期22卷 13-15,21页

作者：崔媛媛张洵颖肖建青西安微电子技术研究所西安710054

从系统验证和FPGA物理原型验证两个方面,分析了TMR结构的注错方式及其验证方法;通过在TMR结构中嵌入注错逻辑,并将所有组TMR寄存器的注错控制信号统一命名,作为系统的输入,根据随机生成的注错信息,索引对应的TMR寄存器,可实现向对用户... 详细信息

从系统验证和FPGA物理原型验证两个方面,分析了TMR结构的注错方式及其验证方法;通过在TMR结构中嵌入注错逻辑,并将所有组TMR寄存器的注错控制信号统一命名,作为系统的输入,根据随机生成的注错信息,索引对应的TMR寄存器,可实现向对用户透明的任意TMR组中注错;将每组TMR寄存器的参考点和观测点引到设计的顶层统一命名,作为待测系统的输出,可适时观测对应TMR寄存器组的注错情况,分析故障电路的行为;为了解决调试机与FPGA板连接的引脚数受限的问题,特别设计了注错控制器和故障收集器;根据具体的注错情况,可编写对应的测试程序,验证设计的正确性,实验结果表明,SOC系统的错误故障率约占18.6%;为系统的可靠性评估提供了依据。

关键词：三模冗余故障注入系统芯片单粒子翻转单粒子瞬态

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基于LBIST的纠检错电路验证方法与实现

计算机测量与控制 2014年第7期22卷 2146-2147,2153页

作者：崔媛媛李振辉张洵颖西安微电子技术研究所西安710054

基于逻辑内建自测试的设计原理,提出了一种针对纠检错电路进行功能自测试的方法,根据纠检错电路具有固定纠检错能力的特点,无需存储海量的比较数据,也不需要设计响应特征分析器对结果数据进行压缩处理,针对具体的纠检错电路,通过增加特... 详细信息

基于逻辑内建自测试的设计原理,提出了一种针对纠检错电路进行功能自测试的方法,根据纠检错电路具有固定纠检错能力的特点,无需存储海量的比较数据,也不需要设计响应特征分析器对结果数据进行压缩处理,针对具体的纠检错电路,通过增加特别设计的注错逻辑可实现任意类型的故障注入,并根据注错信息可对结果进行预测,通过与预期结果比较,可达到验证的目的;最后,以(40,32)海明编码与解码电路为例,实现了其功能自测试结构,并对所有240-1种故障进行了注入与验证;结果表明使用本文的验证方法,可实现纠检错电路的自动化随机验证。

关键词：逻辑内建自测试纠检错电路故障注入单粒子翻转线性反馈移位寄存器

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： Wenxuan zhang Mengran zhang Hongjuan Wang Wen zhang Min zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1).The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： Lele REN Wei zhang Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1:2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,while the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration