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Recent Developments in Metallic Degradable Micromotors for Biomedical and Environmental Remediation Applications

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Nano-Micro Letters 2024年第3期16卷 1-35页

作者： Sourav Dutta Seungmin Noh Roger Sanchis Gual Xiangzhong Chen Salvador Pané Bradley J.Nelson Hongsoo Choi Department of Robotics and Mechatronics Engineering Daegu Gyeongbuk Institute of Science and Technology(DGIST)Daegu 42988Republic of Korea DGIST‑ETH Microrobotics research center DGISTDaegu 42988Republic of Korea Multi‑Scale Robotics Lab Institute of Robotics and Intelligent SystemsETH Zurich8092 ZurichSwitzerland Institute of Optoelectronics State Key Laboratory of Photovoltaic Science and TechnologyShanghai Frontiers Science Research Base of Intelligent Optoelectronics and PerceptionFudan UniversityShanghai 200433People’s Republic of China

Synthetic micromotor has gained substantial attention in biomedicine and environmental ***-based degradable micromotor composed of magnesium(Mg),zinc(Zn),and iron(Fe)have promise due to their nontoxic fuel-free propulsion,favorable biocompatibility,and safe excretion of degradation products Recent advances in degradable metallic micromotor have shown their fast movement in complex biological media,efficient cargo delivery and favorable biocompatibility.A noteworthy number of degradable metal-based micromotors employ bubble propulsion,utilizing water as fuel to generate hydrogen *** novel feature has projected degradable metallic micromotors for active in vivo drug delivery *** addition,understanding the degradation mechanism of these micromotors is also a key parameter for their design and *** propulsion efficiency and life span govern the overall performance of a degradable metallic *** we review the design and recent advancements of metallic degradable ***,we describe the controlled degradation,efficient in vivo drug delivery,and built-in acid neutralization capabilities of degradable micromotors with versatile biomedical ***,we discuss micromotors’efficacy in detecting and destroying environmental ***,we address the limitations and future research directions of degradable metallic micromotors.

关键词： Magnesium Zinc Iron Biodegradable microrobot Biomedical Environmental

Multi-Source Data Privacy Protection Method Based on Homomorphic Encryption and Blockchain

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Computer Modeling in Engineering & Sciences 2023年第7期136卷 861-881页

作者： Ze Xu Sanxing Cao State Key Laboratory of media convergence and Communication Communication University of ChinaBeijing100024China

Multi-Source data plays an important role in the evolution of media *** fusion processing enables the further mining of data and utilization of data value and broadens the path for the sharing and dissemination of media ***,it also faces serious problems in terms of protecting user and data *** privacy protectionmethods have been proposed to solve the problemof privacy leakage during the process of data sharing,but they suffer fromtwo flaws:1)the lack of algorithmic frameworks for specific scenarios such as dynamic datasets in the media domain;2)the inability to solve the problem of the high computational complexity of ciphertext in multi-source data privacy protection,resulting in long encryption and decryption *** this paper,we propose a multi-source data privacy protection method based on homomorphic encryption and blockchain technology,which solves the privacy protection problem ofmulti-source heterogeneous data in the dissemination ofmedia and reduces ciphertext processing *** deployed the proposedmethod on theHyperledger platformfor testing and compared it with the privacy protection schemes based on k-anonymity and differential *** experimental results showthat the key generation,encryption,and decryption times of the proposedmethod are lower than those in data privacy protection methods based on k-anonymity technology and differential privacy *** significantly reduces the processing time ofmulti-source data,which gives it potential for use in many applications.

关键词： Homomorphic encryption blockchain technology multi-source data data privacy protection privacy data processing

A Hybrid and Lightweight Device-to-Server Authentication Technique for the Internet of Things

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Computers, Materials & Continua 2024年第3期78卷 3805-3823页

作者： Shaha Al-Otaibi Rahim Khan Hashim Ali Aftab Ahmed Khan Amir Saeed Jehad Ali Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Science Abdul Wali Khan University MardanMardan23200Pakistan Department of Computer Science and IT UET PeshawarJalozai Campus PeshawarPeshawar24240Pakistan Department of AI convergence Network Ajou UniversitySuwon16499South Korea

The Internet of Things(IoT)is a smart networking infrastructure of physical devices,i.e.,things,that are embedded with sensors,actuators,software,and other technologies,to connect and share data with the respective server *** IoTs are cornerstones in different application domains,the device’s authenticity,i.e.,of server(s)and ordinary devices,is the most crucial issue and must be resolved on a priority ***,various field-proven methodologies were presented to streamline the verification process of the communicating devices;however,location-aware authentication has not been reported as per our knowledge,which is a crucial metric,especially in scenarios where devices are *** paper presents a lightweight and location-aware device-to-server authentication technique where the device’s membership with the nearest server is subjected to its location information along with other ***,media Access Control(MAC)address and Advance Encryption Scheme(AES)along with a secret shared key,i.e.,λ_(i) of 128 bits,have been utilized by Trusted Authority(TA)to generate MaskIDs,which are used instead of the original ID,for every device,i.e.,server and member,and are shared in the offline ***,TA shares a list of authentic devices,i.e.,server S_(j) and members C_(i),with every device in the IoT for the onward verification process,which is required to be executed before the initialization of the actual communication ***,every device should be located such that it lies within the coverage area of a server,and this location information is used in the authentication process.A thorough analytical analysis was carried out to check the susceptibility of the proposed and existing authentication approaches against well-known intruder attacks,i.e.,man-in-the-middle,masquerading,device,and server impersonations,etc.,especially in the IoT ***,proposed authentication and existing state-of-the-art approaches have been s

关键词： Internet of things authenticity security location communication

research on wavelength conversion of triangular pulses with variable symmetry based on SPM effect

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Optoelectronics Letters 2023年第8期19卷 449-454页

作者： YUAN Jin LIU Qisong MEI Ying XU Xiuxiu WANG Yujie BA Xinran State Key Laboratory of media convergence and Communication Communication University of ChinaBeijing 100044China

The generation of periodic triangular waveform with variable symmetrical coefficient based on a dual-parallel Mach-Zehnder modulator(DP-MZM) is demonstrated in this *** properly setting the modulation index and bias points of DP-MZM,desired symmetric/asymmetric triangular waveforms can be *** applying the generated triangular waveform into an amplitude modulator(AM),a single-period signal can be extracted to explore the optical wavelength conversion induced by the self-phase modulation(SPM) effect in a high nonlinear fiber(HNLF).Wavelength shifts of triangular waveforms with different coefficients(10%,20%,30%,40% and 50%) are *** addition,the influence of key parameters of HNLF on the wavelength conversion is analyzed in detail.

关键词： modulator triangular effect

Photonic generation of triangular and rectangular waveforms based on four-wave mixing effect

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Optoelectronics Letters 2022年第1期18卷 6-12页

作者： YUAN Jin WANG Yujie ZHANG Hui ZHANG Mengsi LI Zengrui State Key Laboratory of media convergence and Communication Communication University of ChinaBeijing 100044China

A photonic approach that can generate triangular and rectangular waveforms is proposed.A dual-electrode Mach-Zehnder modulator(De-MZM)is used to fulfill the external optical carrier suppression(OCS)modulation of a continuous wave(CW).The follow-up four-wave mixing(FWM)in a semiconductor optical amplifier(SOA)makes four primary sidebands exist in the *** filtering and optical carrier recovery techniques are used to construct the spectrum aligning with that of a triangular/rectangular *** this work,we also elaborate the influence of errors of key device parameters,by which the feasibility and stability of the system have been *** on this photonic approach,a 10 GHz full-duty-cycle triangular waveform and a 50%-duty-cycle rectangular waveform are successfully *** approach provides a feasible method to generate multiple waveforms.

关键词： spectrum. triangular rectangular

Life:Ordinary World-Speech by Lu Yao at Northwest University in December 1991

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2022年第2期16卷 186-198页

作者： LU Yao JIAO Haimin(record) 不详 Documentary Department Shaanxi Media ConvergenceXi'an 710061China

ⅠI have not done much preparation for today,since it is the end of the year and I have my hands *** the past years,I have had several opportunities to express my opinions,and I do not really have any new ***,I look forward to taking some specific questions from you to exchange our ideas,so I hope this lecture will be rewarding for you.

关键词： really since Northwest

On fine-grained visual explanation in convolutional neural networks

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Digital Communications and Networks 2023年第5期9卷 1141-1147页

作者： Xia Lei Yongkai Fan Xiong-Lin Luo Department of Automation China University of Petroleum BejingBeijing102249China State Key Laboratory of media convergence and Communication Communication University of ChinaBeijing100024China

Existing explanation methods for Convolutional Neural Networks(CNNs)lack the pixel-level visualization explanations to generate the reliable fine-grained decision *** there are inconsistencies between the explanation and the actual behavior of the model to be interpreted,we propose a Fine-Grained Visual Explanation for CNN,namely F-GVE,which produces a fine-grained explanation with higher consistency to the decision of the original *** exact backward class-specific gradients with respect to the input image is obtained to highlight the object-related pixels the model used to make *** addition,for better visualization and less noise,F-GVE selects an appropriate threshold to filter the gradient during the calculation and the explanation map is obtained by element-wise multiplying the gradient and the input image to show fine-grained classification decision *** results demonstrate that F-GVE has good visual performances and highlights the importance of fine-grained decision ***,the faithfulness of the explanation in this paper is high and it is effective and practical on troubleshooting and debugging detection.

关键词： Convolutional neural network Explanation Class-specific gradient Fine-grained

Compact wideband FSS-absorber-based low-RCS reflectarray antenna

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Chinese Journal of Aeronautics 2023年第6期36卷 332-339页

作者： Jianing YANG Yanting ZHANG Ming-Chun TANG Zhehao ZHANG Meijun QU School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of media convergence and Communication Communication University of ChinaBejing 100024 China

This paper presents a method to realize compact broadband low-RCS ReflectArray(RA)antenna based on a Frequency Selective Surface(FSS)absorber and a reflective *** an FSS absorber consists of a resistance-loaded lossy layer and an FSS layer,which is utilized to reach an absorption-transmission *** bottom reflective metasurface works as a phase array,reshaping the quasi-sphere wave from the feeding antenna into the quasi-plane *** a demonstration,the low-RCS RA antenna is simulated,fabricated,and *** simulated and measured results show that the developed low-RCS RA antenna has an aperture efficiency of 42.7%and a gain of 25.4 dBi in the X *** the meantime,it simultaneously reaches the 10 dB RCS reduction for the orthogonal polarizations at the S and C bands,corresponding to a fractal bandwidth of 120%.Specifically,the adopted patch-feeding antenna makes the RA antenna more compact than the horn-feed conventional ***,the proposed RA antenna uses a few layers of substrates,making it lower in cost and easier for *** proposed design may have potential application in integrated stealth communication systems.

关键词： Absorption Broadband RCS reduction Compactness Reflectarray antenna Stealth

Green resource allocation for mobile edge computing

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Digital Communications and Networks 2023年第5期9卷 1190-1199页

作者： Anqi Meng Guandong Wei Yao Zhao Xiaozheng Gao Zhanxin Yang State Key Laboratory of media convergence and Communication Communication University of ChinaBeijing100024China Engineering center of Digital Audio and Video Communication University of ChinaBeijing100024China School of Information and Electronics Beijing Institute of TechnologyBeijing100081China

We investigate the green resource allocation to minimize the energy consumption of the users in mobile edge computing systems,where task offloading decisions,transmit power,and computation resource allocation are jointly *** considered energy consumption minimization problem is a non-convex mixed-integer nonlinear programming problem,which is challenging to ***,we develop a joint search and Successive Convex Approximation(SCA)scheme to optimize the non-integer variables and integer variables in the inner loop and outer loop,***,in the inner loop,we solve the optimization problem with fixed task offloading *** to the non-convex objective function and constraints,this optimization problem is still non-convex,and thus we employ the SCA method to obtain a solution satisfying the Karush-Kuhn-Tucker *** the outer loop,we optimize the offloading decisions through exhaustive ***,the computational complexity of the exhaustive search method is greatly *** reduce the complexity,a heuristic scheme is proposed to obtain a sub-optimal *** results demonstrate the effectiveness of the developed schemes.

关键词： Mobile edge computing Green communications Mixed-integer programming Resource allocation