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PERsPECTIVEs IN MECHANICs OF HETEROGENEOUs sOLIDs

Acta Mechanica solida sinica 2011年第1期24卷 1-26页

作者： C.q. Chen J.Z. Cui H.L. Duan X.q. Feng L.H. He G.K. Hu M.J. Huang Y.Z. Huo B.H. Ji B. Liu X.H. Peng H.J. shi q.P. sun J.X. Wang Y.s. Wang H.P. Zhao Y.P. Zhao q.s. zheng W.N. Zou Department of Engineering Mechanics AML Tsinghua University Beijing 100084 China Academy of Mathematics and systems sciences Chinese Academy of Sciences Beijing 100190 China state Key Laboratory for Turbulence and Complex system and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China CAs Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230026 China school of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced study Nanchang University Nanchang 330031 China Depariment of Mechanics and Engineering sciences Fudan University 220 Handa Road Shanghai 200433 China Department of Mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of Mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China state Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The Micro- and Nano-mechanics Working Group of the Chinese society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica solida sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica solida sinica, its editor-in-chief, Professor q.s. zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of Chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. Finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

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Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： s R Wu B q Wang Z W Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the Reissner-Nordström-de sitter BH surrounded by quintessence(RN-dsq).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dsq under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dsq are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant

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screening for metabolic dysfunction-associated fatty liver disease:Time to discard the emperor’s clothes of normal liver enzymes?

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World Journal of Gastroenterology 2024年第22期30卷 2839-2842页

作者： Chen-Xiao Huang Xiao-Dong Zhou Calvin q Pan Ming-Hua zheng Metabolic Dysfunction-Associated Fatty Liver Disease Research Center Department of HepatologyThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Department of Cardiovascular Medicine The Key Laboratory of Cardiovascular Diseases of WenzhouThe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina Division of Gastroenterology and Hepatology Department of MedicineNew York University Langone HealthNew York University Grossman School of MedicineNew YorkNY 11355United States Institute of Hepatology Wenzhou Medical UniversityKey Laboratory of Diagnosis and Treatment for the Development of Chronic Liver Disease in Zhejiang ProvinceWenzhou 325000Zhejiang ProvinceChina

Metabolic dysfunction-associated fatty liver disease(MAFLD)is the most prevalent chronic liver condition *** liver enzyme-based screening methods have limitations that may missed diagnoses and treatment *** Chen et al,the risk of developing MAFLD remains elevated even when alanine aminotransferase levels fall within the normal ***,there is an urgent need for advanced diagnostic techniques and updated algorithms to enhance the accuracy of MAFLD diagnosis and enable early *** paper proposes two potential screening methods for identifying individuals who may be at risk of developing MAFLD:Lowering these thresholds and promoting the use of noninvasive liver fibrosis scores.

关键词： Metabolic dysfunction-associated fatty liver disease Non-alcoholic fatty liver disease Alanine aminotransferase Liver enzymes screening Noninvasive liver fibrosis scores

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Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser pulses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： q.K.Liu L.Deng q.Wang X.Zhang F.q.Meng Y.P.Wang Y.q.Gao H.B.Cai s.P.Zhu Graduate school China Academy of Engineering PhysicsBeijing 100088China Institute of Applied Physics and Computational Mathematics Beijing 100094China school of Nuclear science and Technology University of Science and Technology of ChinaHefei 230026China shanghai Institute of Laser Plasma Shanghai 201800China HEDPs Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China school of Physics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(BsRs)bursts using particle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity spikes and generating large numbers of hot ***-duration simulations are performed to observe burst events,and a simplified model is developed to eliminate the interference of the broadband laser’s random intensity *** the simplified model,we isolate and characterize the spectrum of electron plasma *** spectrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the spectrum is *** asymmetry is amplified and transferred to electron phase space by high-intensity broadband laser pulses,leading to violent vortex-merging and generation of hot *** proportion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects profoundly influence the BsRs evolution driven by broadband lasers.

关键词： scattering kinetic simplified

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Improved Harris Hawks Algorithm and Its Application in Feature selection

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Computers, Materials and Continua 2024年第1期81卷 1251-1273页

作者： Zhang q. Li Y. Zhan J. Chen s. school of Computer science and Information Engineering Harbin Normal University Harbin 150025 China College of systems Engineering National University of Defense Technology Changsha 410073 China

This research focuses on improving the Harris' Hawks Optimization algorithm (HHO) by tackling several of its shortcomings, including insufficient population diversity, an imbalance in exploration vs. exploitation, and a lack of thorough exploitation depth. To tackle these shortcomings, it proposes enhancements from three distinct perspectives: an initialization technique for populations grounded in opposition-based learning, a strategy for updating escape energy factors to improve the equilibrium between exploitation and exploration, and a comprehensive exploitation approach that utilizes variable neighborhood search along with mutation operators. The effectiveness of the Improved Harris Hawks Optimization algorithm (IHHO) is assessed by comparing it to five leading algorithms across 23 benchmark test functions. Experimental findings indicate that the IHHO surpasses several contemporary algorithms its problem-solving capabilities. Additionally, this paper introduces a feature selection method leveraging the IHHOalgorithm(IHHO-Fs) to address challenges such as lowefficiency in feature selection and high computational costs (time to find the optimal feature combination and model response time) associated with high-dimensional datasets. Comparative analyses between IHHO-Fs and six other advanced feature selection methods are conducted across eight datasets. The results demonstrate that IHHO-Fs significantly reduces the computational costs associated with classification models by lowering data dimensionality, while also enhancing the efficiency of feature selection. Furthermore, IHHO-Fs shows strong competitiveness relative to numerous algorithms. © 2024 The Authors. Published by Tech science Press.

关键词： deep exploitation strategy energy factor update strategy feature selection HHO IHHO population diversity

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Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： s.Tan q.Wang Y.Chen W.B.Yao C.Z.Xiao J.F.Myatt school of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China school of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(sRss)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order sRss and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order sRss propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order sRss,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that sRss and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

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Experimental study of corner separation and unsteady characteristics in linear compressor cascades with and without sweeping jet actuator

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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： s.W.Chen W.H.Li C.Xu q.H.Meng school of Energy science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC shenyang Aircraft Design and Research Institute Shenyang 110035China

sweeping jet actuator(sJA)has been widely applied for activeflow control in *** this paper,the sJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both sJA behaviors and sJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with sJA placed near the separation position,close to the endwall and under *** characteristic frequencies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and sJA jets impact region helped to judge that sJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of sJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control sweeping jet actuator Corner separation Oilflow visualization

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APsO-CNN-sE: An Adaptive Convolutional Neural Network Approach for IoT Intrusion Detection

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Computers, Materials and Continua 2024年第1期81卷 567-601页

作者： Ban Y. Zhang D. He q. shen q. College of Big Data and Information Engineering Guizhou University Guizhou 550025 China

The surge in connected devices and massive data aggregation has expanded the scale of the Internet of Things (IoT) networks. The proliferation of unknown attacks and related risks, such as zero-day attacks and Distributed Denial of service (DDos) attacks triggered by botnets, have resulted in information leakage and property damage. Therefore, developing an efficient and realistic intrusion detection system (IDs) is critical for ensuring IoT network security. In recent years, traditional machine learning techniques have struggled to learn the complex associations between multidimensional features in network traffic, and the excellent performance of deep learning techniques, as an advanced version of machine learning, has led to their widespread application in intrusion detection. In this paper, we propose an Adaptive Particle swarm Optimization Convolutional Neural Network squeeze-and-Excitation (APsO-CNN-sE) model for implementing IoT network intrusion detection. A 2D CNN backbone is initially constructed to extract spatial features from network traffic. subsequently, a squeeze-and-excitation channel attention mechanism is introduced and embedded into the CNN to focus on critical feature channels. Lastly, the weights and biases in the CNN-sE are extracted to initialize the population individuals of the APsO. As the number of iterations increases, the population’s position vector is continuously updated, and the cross-entropy loss function value is minimized to produce the ideal network architecture. We evaluated the models experimentally using binary and multiclassification on the UNsW-NB15 and NsL-KDD datasets, comparing and analyzing the evaluation metrics derived from each model. Compared to the base CNN model, the results demonstrate that APsO-CNN-sE enhances the binary classification detection accuracy by 1.84% and 3.53% and the multiclassification detection accuracy by 1.56% and 2.73% on the two datasets, respectively. Additionally, the model outperforms the

关键词： adaptive particle swarm optimization channel attention mechanism convolutional neural network internet of things Intrusion detection system

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Polynomial-Time Key-Recovery Attacks Against NTRURe Encrypt from AsIACCs'15

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Journal of systems science & Complexity 2024年第3期37卷 1308-1325页

作者： LIU Zhen PAN Yanbin zheng Jinwei school of Cyber science and Technology Hubei Key Laboratory of Applied MathematicsHubei UniversityWuhan 430062China Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China school of Mathematical sciences University of Chinese Academy of SciencesBeijing 100190China

In AsIACCs 2015, Nu nez, et al. proposed a proxy re-encryption scheme, named NTRURe Encrypt, based on NTRU, which allows a proxy to translate ciphertext under the delegator’s public key into a re-encrypted ciphertext that can be decrypted correctly by delegatee’s private key. Because of the potential resistance to quantum algorithm, high efficiency and various applications in real life,NTRURe Encrypt has drawn lots of attention and its security has been widely discussed and *** PqCrypto2019, Liu, et al. proposed two key recovery attacks against it. However, their first attack heavily relies on a weaken decryption oracle, and the second attack needs to collect about 260ciphertexts from the same message by theoretical analysis, which makes both of the attacks unrealistic. In this paper, inspired by the broadcast attack against NTRU, the authors find out that for NTRURe Encrypt the delegator and the delegatee can efficiently recover each other’s private key in polynomial time without any unrealistic assumptions. In addition, the authors also show how to fix NTRURe Encrypt to resist the proposed attacks. As a by-product, the authors also show how to commit broadcast attacks against NTRU 2001 with even dg, which was thought infeasible before.

关键词： Broadcast attack key recovery NTRU NTRUReEncrypt

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An Enhanced Ensemble-Based Long short-Term Memory Approach for Traffic Volume Prediction

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Computers, Materials & Continua 2024年第3期78卷 3585-3602页

作者： Duy quang Tran Huy q.Tran Minh Van Nguyen Faculty of Civil Engineering Nha Trang UniversityNha Trang650000Vietnam Robotics and Mechatronics Research Group Faculty of Engineering and TechnologyNguyen Tat Thanh UniversityHo Chi Minh City700000Vietnam Department of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City700000Vietnam

With the advancement of artificial intelligence,traffic forecasting is gaining more and more interest in optimizing route planning and enhancing service *** volume is an influential parameter for planning and operating traffic *** study proposed an improved ensemble-based deep learning method to solve traffic volume prediction problems.A set of optimal hyperparameters is also applied for the suggested approach to improve the performance of the learning *** fusion of these methodologies aims to harness ensemble empirical mode decomposition’s capacity to discern complex traffic patterns and long short-term memory’s proficiency in learning temporal ***,a dataset for automatic vehicle identification is obtained and utilized in the preprocessing stage of the ensemble empirical mode decomposition *** second aspect involves predicting traffic volume using the long short-term memory ***,the study employs a trial-and-error approach to select a set of optimal hyperparameters,including the lookback window,the number of neurons in the hidden layers,and the gradient descent ***,the fusion of the obtained results leads to a final traffic volume *** experimental results show that the proposed method outperforms other benchmarks regarding various evaluation measures,including mean absolute error,root mean squared error,mean absolute percentage error,and *** achieved R-squared value reaches an impressive 98%,while the other evaluation indices surpass the *** findings highlight the accuracy of traffic pattern ***,this offers promising prospects for enhancing transportation management systems and urban infrastructure planning.

关键词： Ensemble empirical mode decomposition traffic volume prediction long short-term memory optimal hyperparameters deep learning

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