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A Swin Transformer and Residualnetwork Combined Model for Breast Cancer Disease Multi-Classification Using Histopathological Images

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Instrumentation 2024年第1期11卷 112-120页

作者： Jianjun zhuang Xiaohui Wu Dongdong Meng Shenghua jing School of Electronic and Information Engineering Nanjing University of Information Science and TechnologyNanJing 210044China Institute for AI in Medicine School of Artificial IntelligenceNanjing University of Information Science and TechnologyNanjing 210044China Department of Radiation Oncology Jinling HospitalSchool of Medicine Nanjing UniversityNanjing 210002China

Breast cancer has become a killer of women's health *** order to exploit the potential representational capabilities of the models more comprehensively,we propose a multi-model fusion ***,we combine two differently structured deep learning models,ResNet101 and Swin Transformer(SwinT),with the addition of the Convolutional Block Attention Module(CBAM)attention mechanism,which makes full use of SwinT's global context information modeling ability and ResNet101's local feature extraction ability,and additionally the cross entropy loss function is replaced by the focus loss function to solve the problem of unbalanced allocation of breast cancer data *** multi-classification recognition accuracies of the proposed fusion model under 40X,100X,200X and 400X BreakHis datasets are 97.50%,96.60%,96.30 and 96.10%,*** with a single SwinT model and ResNet 101 model,the fusion model has higher accuracy and better generalization ability,which provides a more effective method for screening,diagnosis and pathological classification of female breast cancer.

关键词： breast cancer pathological image swin transformer ResNet101 focal loss

Semi-analytical solution for drained expansion analysis of a hollow cylinder of critical state soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2326-2340页

作者： He Yang Jialiang Zhang Haisui Yu Peizhi zhuang School of Qilu Transportation Shandong UniversityJinan250002China School of Civil Engineering University of LeedsLeedsLS29JTUK

The expansion of a thick-walled hollow cylinder in soil is of non-self-similar nature that the stress/deformation paths are not the same for different soil material *** a result,this problem cannot be solved by the common self-similar-based similarity *** paper proposes a novel,exact solution for rigorous drained expansion analysis of a hollow cylinder of critical state *** stress-dependent elastic moduli of soils,new analytical stress and displacement solutions for the nonself-similar problem are developed taking the small strain assumption in the elastic *** the plastic zone,the cavity expansion response is formulated into a set of first-order partial differential equations(PDEs)with the combination use of Eulerian and Lagrangian descriptions,and a novel solution algorithm is developed to efficiently solve this complex boundary value *** solution is presented in a general form and thus can be useful for a wide range of *** the new solution,the non-self-similar nature induced by the finite outer boundary is clearly demonstrated and highlighted,which is found to be greatly different to the behaviour of cavity expansion in infinite soil *** present solution may serve as a benchmark for verifying the performance of advanced numerical techniques with critical state soil models and be used to capture the finite boundary effect for pressuremeter tests in small-sized calibration chambers.

关键词： Cavity expansion Drained analysis Boundary effect Critical state soil Non-self-similar Eulerian-Lagrangian approach

Bioinspired anti-freezing 3D-printable conductive hydrogel microfibers for highly-sensitive and wide-range detection of ultralow and high strains

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Green Chemical Engineering 2024年第1期5卷 132-143页

作者： yi-Min Yang Ting-Yuan Hu Haidong Fan Lu Shi Shi-Yuan Zhang zhuang Liu Xiao-Jie Ju Rui Xie Wei Wang Liang-yin Chu School of Chemical Engineering Sichuan UniversityChengdu610065China Department of Mechanics Sichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu610065China

Soft strain sensors that can transduce stretch stimuli into electrical readouts are promising as sustainable wearable ***,most strain sensors cannot achieve highly-sensitive and wide-range detection of ultralow and high *** by bamboo structures,anti-freezing microfibers made of conductive poly(vinyl alcohol)hydrogel with poly(3,4-ethylenedioxythiphene)-poly(styrenesulfonate)are developed via continuous microfluidic *** microfibers provide unique bamboo-like structures with enhanced local stress to improve both their length change and resistance change upon stretching for efficient signal *** microfibers allow highlysensitive(detection limit:0.05%strain)and wide-range(0%-400%strain)detection of ultralow and high strains,as well as features of good stretchability(485%strain)and anti-freezing property(freezing temperature:-41.1°C),fast response(200 ms),and good *** experimental results,together with theoretical foundation analysis and finite element analysis,prove their enhanced length and resistance changes upon stretching for efficient signal *** integrating microfluidic spinning with 3D-printing technique,the textiles of the microfibers can be flexibly *** microfibers and their 3D-printed textiles enable highperformance monitoring of human motions including finger bending and throat vibrating during *** work provides an efficient and general strategy for developing advanced conductive hydrogel microfibers as highperformance wearable strain sensors.

关键词： Conductive hydrogel microfibers Microfluidics Sensitive detection Wide detection range Anti-freezing

A Retrodirective Array Enabled by CMOS Chips for Two-Way Wireless Communication with Automatic Beam Tracking

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Engineering 2024年第6期37卷 196-207页

作者： Jiacheng Guo yizhu Shen Guoqing Dong zhuang Han Sanming Hu State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China

This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam *** proposed RDA is enabled by specifically designed chips made using a domestic complementary metal-oxide semiconductor(CMOS)*** highly integrated CMOS chip includes a receiving(Rx)chain,a transmitting(Tx)chain,and a unique tracking phaselocked loop(PLL)for the crucial conjugated phase recovery in the *** article also proposes a method to reduce the beam pointing error(BPE)in a conventional *** validate the above ideas simply yet without loss of generality,a 2.4 GHz RDA is demonstrated through two-way communication links between the Rx and Tx chains,and an on-chip quadrature coupler is designed to achieve a nonretrodirective signal suppression of 23 *** experimental results demonstrate that the proposed RDA,which incorporates domestically manufactured low-cost 0.18 lm CMOS chips,is capable of automatically tracking beams covering±40with a reduced *** CMOS chip in the RDA has a compact size of 4.62 mm^(2) and a low power consumption of 0.15 *** the best of the authors’knowledge,this is the first research to demonstrate an RDA with a fully customized CMOS chip for wireless communication with automatic beam tracking。

关键词： Automatic beam tracking CMOS Retrodirective array Two-way communication

GS-orthogonalization OMP method for space target detection via bistatic space-based radar

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Chinese Journal of Aeronautics 2024年第7期37卷 333-351页

作者： Shuyu ZHENG Libing JIANG Qingwei YANG yingjian ZHAO zhuang WANG National Key Laboratory of Science and Technology on Automatic Target Recognition College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China

A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar ***,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space *** be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization *** solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this ***,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are ***,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space ***,the RCM and DFM are corrected by the compensation function correlated with the estimated motion ***,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo *** simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.

关键词： Bistatic space-based radar High-speed maneuvering space targets detection Range Cell Migration(RCM) Doppler Frequency Migration(DFM) Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm

Staring-imaging satellite pointing estimation based on sequential ISAR images

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Chinese Journal of Aeronautics 2024年第8期37卷 261-276页

作者： Canyu WANG Libing JIANG Weijun ZHONG Xiaoyuan REN zhuang WANG National Key Laboratory of Automatic Target Recognition National University of Defense TechnologyChangsha 410073China Xi’an Satellite Control Center Xi’an 710600China

Pointing estimation for spacecraft using Inverse Synthetic Aperture Radar(ISAR)images plays a significant role in space situational awareness and ***,feature extraction and cross-range scaling of ISAR images create bottlenecks that limit performances of current estimation ***,the emergence of staring imaging satellites,characterized by complex kinematic behaviors,presents a novel challenge to this *** address these issues,this article proposes a pointing estimation method based on Convolutional Neural Networks(CNNs)and a numerical optimization algorithm.A satellite’s main axis,which is extracted from ISAR images by a proposed Semantic Axis Region Regression Net(SARRN),is chosen for investigation in this article due to its unique ***,considering the kinematic characteristic of the staring satellite,an ISAR imaging model is established to bridge the target pointing and the extracted *** on the imaging model,pointing estimation and cross-range scaling can be described as a maximum likelihood estimation problem,and an iterative optimization algorithm modified by using the strategy of random sampling-consistency check and weighted least squares is proposed to solve this ***,the pointing of targets and the cross-range scaling factors of ISAR images are *** experiments based on actual satellite orbital parameters verify the effectiveness of the proposed *** work can improve the performance of satellite reconnaissance warning,while accurate cross-range scaling can provide a basis for subsequent data processes such as 3D reconstruction and attitude estimation.

关键词： Staring-imaging Agile satellite Inverse Synthetic Aperture Radar(ISAR) Pointing estimation Cross-range scaling

Security-Enhanced Directional Modulation Based on Two-Dimensional M-WFRFT

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China Communications 2024年第5期21卷 229-248页

作者： Zhou zhuang Luo Junshan Wang Shilian Xia Guojiang School of Electronic Science National University of Defense TechnologyChangsha 410073China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

Directional modulation(DM)is one of the most promising secure communication ***,when the eavesdropper is co-located with the legitimate receiver,the conventional DM has the disadvantages of weak anti-scanning capability,anti-deciphering capability,and low secrecy *** response to these problems,we propose a twodimensional multi-term weighted fractional Fourier transform aided DM scheme,in which the legitimate receiver and the transmitter use different transform terms and transform orders to encrypt and decrypt the confidential *** order to further lower the probability of being deciphered by an eavesdropper,we use the subblock partition method to convert the one-dimensional modulated signal vector into a twodimensional signal matrix,increasing the confusion of the useful *** results demonstrate that the proposed DM scheme not only provides stronger anti-deciphering and anti-scanning capabilities but also improves the secrecy rate performance of the system.

关键词： bit error rate directional modulation phased array secrecy rate weighted fractional Fourier transform

Progress on Bionic Textured Cutting Tools:A Review and Prospects

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Journal of Bionic Engineering 2024年第1期21卷 19-55页

作者： Hong Wei Guangjun Chen zhuang Chen Zhiwei Yu Jiashuai Huang Tianjin Key Laboratory of High Speed Cutting and Precision Processing Tianjin 300222China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

Cutting tools are known as the“productivity”of the manufacturing industry,which affects the production efficiency and quality of the workpiece,and has become the focus of research and attention in academia and ***,traditional cutting tools often suffer from adhesion or wear during the cutting process,which considerably reduces the cutting efficiency and service life of the tools,and makes it difficult to meet current production *** solve the above problems,scholars have introduced bionics into the tool’s design,applying the microscopic structure of the biological surface to the tool surface to alleviate the tool’s *** paper mainly summarizes the research progress of bionic textured cutting ***,categorize whether the bionic texture design is inspired by a single organism or multiple ***,it is discussed that the non-smooth surface of the biological surface has five characteristics:hydrophilic lubricity,wear resistance,drag reduction and hydrophobicity,anti-adhesion,and arrangement,and the non-smooth structure of these different characteristics are applied to the surface of the tool is designed with bionic ***,the cutting performance of bionic textured cutting tools is *** anti-friction and wear-resisting mechanism of bionic textured cutting tools is ***,some pending problems and perspectives have been proposed to provide new inspirations for the design of bionic textured cutting tools.

关键词： Bionic textured cutting tools Biological microstructure characteristics Cutting performance Anti-friction and wear-resisting mechanism

Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 289-296页

作者： Yanpeng Wei Jiale Zhao Jian zhuang Peng Zhang Zhiwu Han College of Biological and Agricultural Engineering Jilin UniversityChangchun 130025China Key Laboratory of Bionics Engineering Ministry of EducationJilin UniversityChangchun 130025China Weichai Lovol Heavy Industry Co. LTDWeifang 261031China

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic ***,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy *** paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and ***,in this paper,corn starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic *** that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding *** test results shown that the addition of basalt fibers alone led to a reduction in the strength of the *** of 0.1 wt%SNC on the surface of basalt fibers can make the strength consistent with pure epoxy *** the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy *** is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress concentration and the development of *** enhances the binding of basalt *** conclusions of this paper can provide an effective,simple,low-cost and non-polluting method of interfacial enhancement modification.

关键词： Basalt fibres Epoxy resin Fibre reinforced composites Starch nanocrystals Eco-friendly