检索结果-内蒙古大学图书馆

An Efficient Coherent Integration Method for Highly Maneuvering Target Detection by Exploiting Range-Azimuth Coupling Relationships Between Subsegments

引用

IEEE Sensors Journal 2025年第9期25卷 15456-15476页

作者： Wan, Jun Jiang, Xinyu Liu, Chengyuan Li, Dong Xie, Xiaoran Sang, Qinglin Chen, Zhanye Chongqing University School of Microelectronics and Communication Engineering Chongqing Key Laboratory of Space Information Network and Intelligent Information Fusion Chongqing400044 China China Academy of Electronics and Information Technology Beijing100041 China State Key Laboratory of Millimeter Waves Institute of Electromagnetic Space Southeast University Nanjing210096 China

Arbitrary-order range migrations (RMs) and Doppler frequency migrations (DFMs) caused by complicated motions of highly maneuvering targets (HMTs) pose challenges for coherent integration (CI) in radar remote sensing and detection applications. Complicated Doppler frequency ambiguity improves the challenges of CI for HMTs. The optimal generalized Radon-Fourier transform (GRFT) suffers from a large computational cost, and nonlinear transform-based methods are affected by severe performance loss. To tackle these difficulties, an efficient segmented CI method for HMT detection via the range-azimuth coupling relationship between subsegments is proposed. First, inspired by the advantage of subaperture processing, a segmentation operation is introduced to remove intrasegment RMs and DFMs. Second, a high-order compensation function is presented to remove the high-order intersegment RMs and DFMs. Third, by exploiting the range-azimuth coupling relationship between subsegments, a residual migration compensation function is used to correct the residual intersegment RM. Thus, a well result of HMT's CI is achieved. The proposed method handles arbitrary-order RMs and DFMs, complex Doppler ambiguity, and ambiguous speed sidelobes (BSSLs) in low signal-to-noise ratio (SNR) circumstances and multitarget cases due to its linear transform property. In comparison to the optimal GRFT, the proposed approach substantially lowers computational cost while showing similar performance. Then, the presented approach can be implemented by parallel processing. It is advantageous to enhance real-time processing efficiency. Several real radar data are analyzed to confirm the effectiveness of the developed method. © 2001-2012 IEEE.

关键词： Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Recent progress on photoactive nonprecious transition-metal complexes

引用

Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term *** are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,*** review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal *** addition,a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

来源：评论

学校读者我要写书评

暂无评论

Doublecarbohelicene:facile synthesis,chiroptical properties,isomerization study,and lasing application

引用

Science China Chemistry 2025年第1期68卷 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Physics and Electronic Science Engineering Research Center of Nanophotonics&Advanced InstrumentMinistry of EducationEast China Normal UniversityShanghai 200241China State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Institute of Polymer Optoelectronic Materials&Devices State Key Laboratory of Luminescent Materials&DevicesSouth China University of TechnologyGuangzhou 510640China

Double carbohelicenes have attracted considerable attention due to their aesthetic structures,distinctπ-conjugation extension,inherent chirality,and intriguing optical and electronic ***,the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties,isomerization process and lasing application is presented.1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key *** is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM,which were successfully isolated and unambiguously confirmed by Xray *** optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography(HPLC),and 1-PP and 1-MM were characterized by circular ***,it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating,and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated.1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%.Consequently,we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously,which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm^(-2).We believe that our studies,including the facile synthesis methodology,detailed isomerization studies,and lasing application,will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

来源：评论

学校读者我要写书评

暂无评论

A novel high-frequency cutting force compensation model for micro-milling polyvinylidene fluoride thin films tri-axis force sensors based on machine learning algorithms

引用

Precision engineering 2025年 95卷 188-202页

作者： Huang, Haizhong Zhao, Honghao Zhang, Chongtian Wang, Yanshen Liu, Huiying School of Energy and Power Engineering Nanjing University of Science and Technology Nanjing210094 China Department of Mechanical Engineering Harbin Institute of Technology at Weihai Weihai264209 China State Key Laboratory of Tribology in Advanced Equipment Tsinghua University Beijing100084 China

During micro-milling processes, real-time high-precision monitoring of cutting forces is crucial. In this study, a high-frequency micro cutting force sensor based on polyvinylidene fluoride thin films was developed. The data obtained from the micro cutting force sensor were compared with actual cutting force measurements, leading to the construction of a cutting force compensation model utilizing three machine learning algorithms: extreme gradient boosting, least squares boosting, and gaussian kernel regression. A comparative analysis of these three algorithms revealed that the gaussian kernel Regression algorithm excels in accurately constructing the cutting force compensation model, while the least squares boosting algorithm demonstrates substantial robustness. This study provides a method for constructing a cutting force signal compensation model and offers a new intelligent monitoring approach for subsequent research. © 2025 Elsevier Inc.

关键词： Milling (machining)

来源：评论

学校读者我要写书评

暂无评论

Large-scale high uniform optoelectronic synapses array for artificial visual neural network

引用

Microsystems & Nanoengineering 2025年第1期11卷 247-256页

作者： Fanqing Zhang Chunyang Li Zhicheng Chen Haiqiu Tan Zhongyi Li Chengzhai Lv Shuai Xiao Lining Wu Jing Zhao State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyMinistry of Education100081 BeijingChina School of Mechatronical Engineering Beijing Institute of Technology100081 BeijingChina Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology100081 BeijingChina Laser Micro/Nano Fabrication Laboratory School of Mechanical EngineeringBeijing Institute of Technology100081 BeijingChina School of Mechanical Engineering Beijing Institute of Technology100081 BeijingChina

Recently,the biologically inspired intelligent artificial visual neural system has aroused enormous ***,there are still significant obstacles in pursuing large-scale parallel and efficient visual memory and *** this study,we demonstrate a 28×28 synaptic devices array for the artificial visual neuromorphic system,within the size of 0.7×0.7 cm 2,which integrates sensing,memory,and processing *** highly uniform floating-gate synaptic transistors array were constructed by the wafer-scale grown monolayer molybdenum disulfide with Au nanoparticles(NPs)acting as the electrons capture *** synaptic plasticity behaviors have been achieved owing to the switchable electronic storage *** excellent optical/electrical coordination capabilities were implemented by paralleled processing both the optical and electrical signals the synaptic array of 784 devices,enabling to realize the badges and letters writing and erasing ***,the established artificial visual convolutional neural network(CNN)through optical/electrical signal modulation can reach the high digit recognition accuracy of 96.5%.Therefore,our results provide a feasible route for future large-scale integrated artificial visual neuromorphic system.

关键词： optoelectronic synapses monolayer molybdenum disulfide artificial visual neural system convolutional neural network artificial visual neuromorphic systemwithin artificial visual neural network floating gate transistors synaptic plasticity

来源：评论

学校读者我要写书评

暂无评论

Editorial for Special Issue on Contact Electrification

引用

Friction 2025年第2期13卷 1-2页

作者： Shiquan Lin Chi Zhang Tianmin Shao School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Contact electrification is a pervasive and complex phenomenon that has been known for more than 2,600 years,and its mechanisms have been debated for decades but remain ***,contact electrification has long been considered an unpredictable effect,which has hindered its *** recent years,the study of contact electrification is in full swing,its mechanism has been analyzed in great depth,and its role in tribology,chemistry,biology,etc.,has been increasingly *** on the phenomenon of contact electrification,various sensing and energy harvesting devices have been *** the past decade,research on the mechanism and application of contact electrification has made great progress,and this phenomenon has become a hot spot in the tribological research community.

关键词： mechanism harvesting contact

来源：评论

学校读者我要写书评

暂无评论

Bioinspired Sensing of Undulatory Flow Fields Generated by Leg Kicks in Swimming

引用

IEEE Transactions on Automation Science and engineering 2025年 22卷 13895-13906页

作者： Wang, Jun Shen, Tongsheng Zhao, Dexin Zhang, Feitian Peking University State Key Laboratory of Turbulence and Complex Systems College of Engineering Department of Advanced Manufacturing and Robotics Beijing100871 China National Innovation Institute of Defense Technology Beijing100071 China

The artificial lateral line (ALL) is a bioinspired flow sensing system for underwater robots, comprising of distributed flow sensors. The ALL has been successfully applied to detect the undulatory flow fields generated by body undulation and tail-flapping of bioinspired robotic fish. However, its feasibility and performance in sensing the undulatory flow fields produced by human leg kicks during swimming have not been systematically tested and studied. This paper presents a novel sensing framework to investigate the undulatory flow field generated by swimmer’s leg kicks, leveraging bioinspired ALL sensing. To evaluate the feasibility of using the ALL system for sensing the undulatory flow fields generated by swimmer leg kicks, this paper designs an experimental platform integrating an ALL system and a lab-fabricated human leg model. To enhance the accuracy of flow sensing, this paper proposes a feature extraction method that dynamically fuses time-domain and time-frequency characteristics. Specifically, time-domain features are extracted using one-dimensional convolutional neural networks and bidirectional long short-term memory networks (1DCNN-BiLSTM), while time-frequency features are extracted using short-term Fourier transform and two-dimensional convolutional neural networks (STFT-2DCNN). These features are then dynamically fused based on attention mechanisms to achieve accurate sensing of the undulatory flow field. Furthermore, extensive experiments are conducted to test various scenarios inspired by human swimming, such as leg kick pattern recognition and kicking leg localization, achieving satisfactory results. © 2004-2012 IEEE.

关键词： Long short-term memory

来源：评论

学校读者我要写书评

暂无评论

Thermal Balance-Based Evaluation Method for Safe Operating Areas and Its Degradation of IGBT Power Module

引用

IEEE Journal of Emerging and Selected Topics in Power Electronics 2025年

作者： Han, Tongyao Luo, Yifei Liu, Binli Yuan, Hao Shi, Zenan Naval University of Engineering National Key Laboratory of Electromagnetic Energy China Huazhong University of Science and Technology State Key Laboratory of Advanced Electromagnetic Engineering and Technology Wuhan430033 China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong University Xi’an710049 China

Insulated gate bipolar transistors (IGBTs) power module experience significant thermal stress during short-time overload conditions, and their electro-thermal characteristics exhibit strong nonlinearities. As a result, the two-dimensional safe operating area (SOA) provided in the datasheet is unable to meet the need of device reliability assessments. In this paper, we propose a quantitative assessment method based on the thermal balance principle to define the SOA for IGBTs and assess its degradation. A three-dimensional SOA that incorporates voltage, current, and junction temperature is established to prevent IGBT from thermal failures. The proposed SOA indicates that IGBT can operate safely at more than twice the rated current, and the junction temperature can exceed 448.15K(175° C) without thermal failures. This work provides theoretical support for IGBT application design and reliability assessment. According to the physical mechanisms associated with thermal failures of IGBT power module, a criterion to characterize the thermal instability of devices is established. Further, the net heat flux analysis model that integrates semiconductor physics with heat conduction theory is established, enabling the formulation of the three-dimensional SOA of IGBT. Moreover, the effects of the degradation of electro-thermal characteristics on the SOA throughout the long-term operation of the device is considered. In addition, an electro-thermal coupling model that simulates the electro-thermal characteristics of the device is established. The results from both simulation and experiment demonstrate that the established SOA and its degradation effectively predict the reliability of the IGBT under short-time overload conditions. © 2013 IEEE.

关键词： Insulated gate bipolar transistors (IGBT)

来源：评论

学校读者我要写书评

暂无评论

A Highly Sensitive Piezoresistive Electronic Skin: Coulomb Blockade-Favored Dynamic Conduction Paths in Micellar Brush-Templated Metal Nanoarrays

引用

Chemistry of Materials 2025年第9期37卷 3274-3283页

作者： Lu, Yao Xing, Yurui Tao, Jiawei Wang, Shuang Lin, Geyu Zhang, Hongti Qiu, Huibin School of Chemistry and Chemical Engineering State Key Laboratory of Synergistic Chem-Bio Synthesis Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study State Key Laboratory of Micro-Nano Engineering Science Shanghai Jiao Tong University Shanghai200240 China School of Physical Science and Technology Shanghai Key Laboratory of High-resolution Electron Microscopy ShanghaiTech University Shanghai201210 China

The creation of tailored micro-nanostructures frequently brings intriguing features to flexible electronic skins (E-skins). However, the construction of nanoscale architectures on soft substrates under mild conditions remains a critical challenge. Herein, we report a facile micellar brush-templated strategy for the precise fabrication of conductive metal nanoarrays on diverse flexible substrates. Erect micelle/Pt-nanoarrays with precisely tunable heights are prepared through surface-initiated living growth of cylindrical micellar brushes followed by the dense decoration of Pt nanoparticles at an ambient temperature. The stacking of nanoparticles imparts distinctive electron transport characteristics, facilitating the establishment of dynamic conductive pathways during interlocking and resulting in substantial enhancement of pressure sensitivity. Thus, the micelle/Pt-nanoarray-based E-skin reveals remarkably high sensitivity over a wide pressure range, enabling comprehensive detection capabilities encompassing foot pressure, finger bending, wrist pulse, and weak gas flow. Moreover, these conductive metal nanoarrays can be readily fabricated on soft substrates with a tortuous surface, favoring the formation of hierarchically structured E-skin with linear response across a broad scale. © 2025 American Chemical Society.

关键词： Metal nanoparticles

来源：评论

学校读者我要写书评

暂无评论

Enhanced strength-ductility synergy of Mg/Al laminate by coordinating the strain gradient of constituting layers

引用

Journal of Materials Science and technology 2025年 233卷 264-279页

作者： Qian, Lihua Chen, Liang Tang, Jianwei Li, Yefei Zhang, Cunsheng Kong, Xiangshan State key Laboratory of Advanced Equipment and Technology for Metal Forming Shandong University Jinan250061 China Shandong University Jinan250061 China State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an710049 China School of Mechanical Engineering Xinjiang University Urumqi830047 China

Mg/Al laminate with ZK60Mg and TiB2/6061Al as constitute layers was fabricated through the porthole die co-extrusion and hot rolling. The effects of rolling and roll temperatures on the microstructure, interfacial structure, mechanical properties, and crack propagation paths were studied. The results show that the intermetallic compounds layer shows an intermittent form. The strong strain/dislocation hardening ability of Mg/Al laminate is attributed to the coupled effects of interlocking Al/β interface, strain gradient, and β layer with nanotwins and stacking faults. The complex dislocation structures such as network, loop, and array are found in the Al layer. Dislocation slip is the main deformation mode of the Al layer, while dislocation slip and dynamic recrystallization are the main deformation modes of the Mg layer. As roll temperature increases, prismatic 〈a〉 slip replaces the basal 〈a〉 slip as the most important slip mode. At a rolling temperature of 400 °C and a roll temperature of 150 °C, an optimal synergy of mechanical properties is achieved, with ultimate tensile strength, shear strength, and elongation of 262.1 MPa, 36.4 MPa, and 18.1 %, respectively. As the rolling temperature increases, the fracture mode of Mg/Al laminate changes from discontinuous plastic shrinkage to transverse and longitudinal cracks. With increasing the roll temperature, the through cracks tend to form, indicating the plasticity and bonding quality of Mg/Al laminate are effectively enhanced. © 2025

关键词： Dynamic recrystallization

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：