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一种稳健的窄带反馈型主动噪声控制系统

仪器仪表学报 2024年第1期45卷 269-277页

作者：马亚平胡计昶吴定会毕勤胜路静江南大学物联网工程学院无锡214122 江苏大学镇江212013 无锡和烁丰科技股份有限公司无锡214142

传统窄带反馈型主动噪声控制系统采用并型自适应滤波器结构,用于合成参考信号时,仍存在参考信号合成质量较差、滤波器权值的初值设置难度高、应对非平稳窄带噪声的能力不足等问题。为解决以上问题,通过引入高效的串并型自适应滤波器结... 详细信息

传统窄带反馈型主动噪声控制系统采用并型自适应滤波器结构,用于合成参考信号时,仍存在参考信号合成质量较差、滤波器权值的初值设置难度高、应对非平稳窄带噪声的能力不足等问题。为解决以上问题,通过引入高效的串并型自适应滤波器结构来合成参考信号,提出新型的窄带反馈型主动噪声控制系统,改善参考信号合成质量,进而提升系统的整体降噪性能。新型系统不仅有效解决了传统系统存在的参考信号合成质量较差的问题,还降低了滤波器权值的初值设置复杂度,同时还提升了系统应对非平稳窄带噪声的能力。实验结果表明,新型系统较传统系统的前后两部分的降噪量分别提升了7.89和9.18 dB。仿真和实验结果共同验证了提出的系统较传统系统具有更强的稳健性和降噪性能。

关键词：反馈型主动噪声控制自适应滤波器窄带噪声滤波-X最小均方算法降噪性能

Enhanced thermoelectric and mechanical properties of bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li Ming-Wei Zhang Ji-wu Xin Lei Wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

Enhanced interfacial charge transfer on bi metal@defective bi_(2)Sn_(2)O_(7) quantum dots towards improved full-spectrum photocatalysis:A combined experimental and theoretical investigation

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Chinese Chemical Letters 2024年第6期35卷 507-514页

作者： Huizhong wu Ruiheng Liang Ge Song Zhongzheng Hu Xuyang Zhang Minghua Zhou Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China

To mitigate the water pollution problem by photocatalytic degradation of typical antibiotics of tetracycline(TC),we prepared defective bi_(2)Sn_(2)O_7(BSO)quantum dots(QDs)with a full spectral response due to bi metal deposition,using a one-pot hydrothermal method,labeled as bi@*** optimized bi@BSOOV showed 73.4% removal of TC in 1 h under irradiation with a 50 W LED lamp in the wavelength band in the visible-near-infrared(vis-NIR)light,a rate that is substantially greater than that of pure BSO(14.7%).The synergistic interaction of bi metal and oxygen vacancies(OVs)is crucial to boosting photocatalytic *** near-infrared region of the photo-response is extended by the surface plasmon resonance(SPR)effect of bi metal,enhancing the photocatalytic performance and dramatically raising the efficiency of solar energy *** addition to inducing defect levels in BSO,the OVs also activate the surface adsorbed O_(2) to promote the production of·O_(2)^(-)and ^(1)O_(2).DFT calculations reveal that bi metal and OVs can mutually tune the charge transfer *** the one hand,bi metal can act as both a charge transfer bridge and an electron donor to assist charge *** the other hand,OVs-induced defect levels allow electrons that leap to the conduction band(CB)to first leap from the valence band(VB)to the defect levels,notably improving interfacial charge separation and *** concept of design executed in this study for altering the catalyst by introducing both OVs and bi metal can provide a rational design idea and potential insight for improving the photocatalytic activity for environmental applications.

关键词： bi metal bi_(2)Sn_(2)O_7 quantum dots Surface plasmon resonance Oxygen vacancies

江山乌猪肠道黏膜菌群组成及其功能的性别差异

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微生物学报 2024年第4期64卷 1249-1262页

作者：吴娴毕海洋武永淑李向臣张亚南浙江农林大学动物科技学院·动物医学院浙江省畜禽绿色生态健康养殖应用技术研究重点实验室浙江杭州311300

肠道黏膜微生物在调控宿主生理功能方面发挥重要作用,其结构组成受到多种因素影响。性别被认为是塑造肠道微生物的因素之一。然而,性别对肠道黏膜菌群的差异影响还不清楚。【目的】以江山乌猪为研究对象,探究性别差异对其肠道黏膜微生... 详细信息

肠道黏膜微生物在调控宿主生理功能方面发挥重要作用,其结构组成受到多种因素影响。性别被认为是塑造肠道微生物的因素之一。然而,性别对肠道黏膜菌群的差异影响还不清楚。【目的】以江山乌猪为研究对象,探究性别差异对其肠道黏膜微生物组成及功能的影响。【方法】选取性成熟的雌性和雄性江山乌猪各8头,利用16S rRNA基因高通量测序技术分析回肠和结肠黏膜菌群。【结果】在回肠黏膜中,雄性江山乌猪菌群的Chao1指数和Shannon指数显著高于雌性(P0.05)。菌群差异分析显示,回肠黏膜中,沙雷氏菌属(Serratia)和埃希氏志贺菌属(Escherichia_Shigella)在雌性组中的相对丰度显著高于雄性组(P<0.05),雄性组中Oscillospiraceae UCG-005、拟普雷沃氏菌属(Alloprevotella)、布劳特氏菌属(Blautia)和Prevotellaceae_NK3B31_group相对丰度显著高于雌性组(P<0.05);结肠黏膜中,雌性组中unclassified_Muribaculaceae、Rikenellaceae_RC9_gut_group和Prevotellaceae UCG-003相对丰度显著高于雄性组(P<0.05),Oscillospiraceae UCG-005、Lachnospiraceae_NK4A136_group和unclassified_Lachnospiraceae在雄性组中相对丰度更高(P<0.05)。功能预测发现,雄性乌猪回肠黏膜菌群显著富集了氨基酸代谢、碳水化合物代谢和能量代谢等功能途径(P<0.05);结肠黏膜菌群主要富集了膜转运相关的ABC转运蛋白和信号转导相关的双组分系统等功能途径(P<0.05)。【结论】不同性别江山乌猪肠黏膜菌群结构及功能具有明显差异。这些结果揭示了不同性别江山乌猪肠道黏膜菌群的差异特征,为了解和挖掘我国地方畜禽品种肠道微生物资源提供部分参考。

关键词：性别肠黏膜微生物微生物功能江山乌猪

明清插图本《牡丹亭》中的“写真”图研究——以石林居士序刻本为中心

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浙江理工大学学报（社会科学版） 2024年第2期52卷 215-222页

作者：李碧吴强浙江理工大学艺术与设计学院杭州310018

明清插图本《牡丹亭》中的图像内容、构图版式和传播路径蕴含着丰富的文化功能与意义,而学界对《牡丹亭》中特定插图的研究并不多。文章以其中的“写真”图为研究对象,分析不同版本的插图内容与其变化过程。研究发现:石林居士版的“写... 详细信息

明清插图本《牡丹亭》中的图像内容、构图版式和传播路径蕴含着丰富的文化功能与意义,而学界对《牡丹亭》中特定插图的研究并不多。文章以其中的“写真”图为研究对象,分析不同版本的插图内容与其变化过程。研究发现:石林居士版的“写真”图具有经典性和独创性,既体现在杜丽娘“三重画像”的独特图绘模式所蕴含的创作理念,又表现在后来的出版物对其不断模仿与翻刻;明清两代不同版本“写真”图的创作与改写,反映了特定时期的文化趣味和审美意识,以及不同群体对戏曲文本的接受理解;插图创作传统悠久,从同一系列的“写真”图比较中考察插图的演变规律与功能,可以进一步发掘古代戏曲插图的发展状况与艺术价值。

关键词：《牡丹亭》插图石林居士序刻本戏曲经典性视觉性

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切换式多无人机协同目标追踪策略

计算机应用与软件 2024年第7期41卷 74-81,99页

作者：吴杰宏杨京辉毕静沈阳航空航天大学计算机学院辽宁沈阳110136

针对现有的追踪策略在保持网络拓扑连通性和捕获目标成功率方面的不足,提出一种切换式目标追踪策略(STS)。考虑实际中只有部分无人机节点可以探测到目标的情况,通过卡尔曼一致性滤波获得对目标的最优估计;根据无人机与目标之间的距离变... 详细信息

针对现有的追踪策略在保持网络拓扑连通性和捕获目标成功率方面的不足,提出一种切换式目标追踪策略(STS)。考虑实际中只有部分无人机节点可以探测到目标的情况,通过卡尔曼一致性滤波获得对目标的最优估计;根据无人机与目标之间的距离变化,设置不同的运动方程;通过lyapunov方法进行理论分析。仿真实验表明,该策略在目标运动轨迹单一的情况下,成功率达到98%,在考虑目标存在逃逸行为的情况下,成功率为95%,且追踪过程中始终保持网络的连通性和避免无人机之间发生碰撞。

关键词：协同目标追踪动态网络卡尔曼一致性滤波切换式策略 lyapunov方法

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滑坡特征参数的选取探讨及应用研究

工程与建设 2024年第2期38卷 323-325,336页

作者：吴必胜南宁市勘测设计院集团有限公司广西南宁530021

为有效保证滑坡灾害防治效果,本文先开展滑坡特征参数的选取探讨,并以其结果开展滑坡稳定性评价的应用研究。分析结果表明:滑坡滑带土的抗剪参数求解方法主要有三类,即土工试验法、参数反算法及工程经验法,各类方法的适用性存在一定差异... 详细信息

为有效保证滑坡灾害防治效果,本文先开展滑坡特征参数的选取探讨,并以其结果开展滑坡稳定性评价的应用研究。分析结果表明:滑坡滑带土的抗剪参数求解方法主要有三类,即土工试验法、参数反算法及工程经验法,各类方法的适用性存在一定差异,本文提出以三类方法求得结果的平均值作为最终抗剪参数值;通过抗剪参数的稳定性应用评价,得出滑坡现状整体处于基本稳定至欠稳定状态,剩余下滑力为100.29~129.80 N/m,为滑坡防治提供了理论依据,值得推广应用。

关键词：滑坡特征参数地质条件稳定性评价

Macroscopic polarization enhancement boosting piezo-photocatalytic performance via Nb-doping on B-site of bi_(4)Ti_(3)O_(12)nanosheets

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Journal of Advanced Ceramics 2024年第4期13卷 437-446页

作者： Hongjian Yu Xindong Wei Min Wang Yan Zhang Zheng wu Fan Guo Jie Han School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Material Sciences and TechnologyChina University of Geosciences(Beijing)Beijing 100083China School of Environmental and Chemical Engineering Xi’an Key Laboratory of Textile Chemical Engineering AuxiliariesXi'an Polytechnic UniversityXi'an 710048China

The development of a high-performance ferroelectric piezo-photocatalyst is an efficient strategy for advancing sustainability within the environmental and energy ***,a major challenge lies in the creation of a strong polarized electric field that can effectively hinder charge recombination,both within the bulk and on the surface of ***,we synthesize a series of Nb-doped bi_(4)Ti_(3)O_(12)nanosheets via a facile one-pot hydrothermal method to achieve synergistically enhanced piezo-photocatalytic performance in CO_(2)reduction and pollutant *** optimized doped bi_(4)Ti_(3)O_(12)demonstrates remarkable efficiency in the conversion of CO_(2)into CO,with a high production rate of 72.7μmol∙g−1∙h−1 without using co-catalysts or any sacrificial agent,surpassing the performance of unmodified bi_(4)Ti_(3)O_(12)by up to 4.69 ***,our catalyst demonstrates ultra-fast piezo-photocatalytic degradation of organic pollutant Rhodamine B(RhB)at low concentrations and exceptional piezo-photocatalytic activity at high concentrations,outperforming most previously reported state-of-the-art *** systematic corroboration of catalyst characterization and experimental analysis reveals that the synergistic effect arises from the amplified macroscopic polarization induced by lattice distortion caused by the larger Nb ions,thereby improving piezo-photocatalytic *** research thus offers valuable insights into the direct design and fabrication of versatile catalytic systems,with applications spanning CO_(2)valorization and beyond.

关键词： CO_(2)reduction dye degradation piezo-photocatalysis Nb-doped bi_(4)Ti_(3)O_(12) macroscopic polarization regulation

big Data Access Control Mechanism Based on Two-Layer Permission Decision Structure

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Computers, Materials & Continua 2024年第4期79卷 1705-1726页

作者： Aodi Liu Na Wang Xuehui Du Dibin Shan Xiangyu wu Wenjuan Wang He’nan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policymanagement efficiency and difficulty in accurately describing the access control policy. To overcome theseproblems, this paper proposes a big data access control mechanism based on a two-layer permission decisionstructure. This mechanism extends the attribute-based access control (ABAC) model. Business attributes areintroduced in the ABAC model as business constraints between entities. The proposed mechanism implementsa two-layer permission decision structure composed of the inherent attributes of access control entities and thebusiness attributes, which constitute the general permission decision algorithm based on logical calculation andthe business permission decision algorithm based on a bi-directional long short-term memory (biLSTM) neuralnetwork, respectively. The general permission decision algorithm is used to implement accurate policy decisions,while the business permission decision algorithm implements fuzzy decisions based on the business *** biLSTM neural network is used to calculate the similarity of the business attributes to realize intelligent,adaptive, and efficient access control permission decisions. Through the two-layer permission decision structure,the complex and diverse big data access control management requirements can be satisfied by considering thesecurity and availability of resources. Experimental results show that the proposed mechanism is effective andreliable. In summary, it can efficiently support the secure sharing of big data resources.

关键词： big data access control data security biLSTM