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Performance analysis of mobile ad hoc networks under flooding attacks

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Journal of Systems Engineering and Electronics 2011年第2期22卷 334-339页

作者： Ping yi Futai Zou Yan Zou Zhiyang Wang School of Information Security Engineering Shanghai Jiaotong University Shanghai 200030 P. R. China The State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 P. R. China

Due to their characteristics of dynamic topology, wireless channels and limited resources, mobile ad hoc networks are particularly vulnerable to a denial of service （DoS） attacks launched by intruders. The effects of flooding attacks in network simulation 2 （NS2） and measured performance parameters are investigated, including packet loss ratio, average delay, throughput and average number of hops under different numbers of attack nodes, flooding frequency, network bandwidth and network size. Simulation results show that with the increase of the flooding frequency and the number of attack nodes, network performance sharply drops. But when the frequency of flooding attacks or the number of attack nodes is greater than a certain value, performance degradation tends to a stable value.

关键词： mobile ad hoc network security flooding attack.

Label distribution for multimodal machine learning

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Frontiers of Computer Science 2022年第1期16卷 33-43页

作者： yi REN Ning XU Miaogen LING Xin GENG Department of Computer Science and Engineering Southeast UniversityNanjing211189China

Multimodal machine learning(MML)aims to understand the world from multiple related *** has attracted much attention as multimodal data has become increasingly available in real-world *** is shown that MML can perform better than single-modal machine learning,since multi-modalities containing more information which could complement each ***,it is a key challenge to fuse the multi-modalities in *** from previous work,we further consider the side-information,which reflects the situation and influences the fusion of *** recover multimodal label distribution(MLD)by leveraging the side-information,representing the degree to which each modality contributes to describing the ***,a novel framework named multimodal label distribution learning(MLDL)is proposed to recover the MLD,and fuse the multimodalities with its guidance to learn an in-depth understanding of the jointly feature ***,two versions of MLDL are proposed to deal with the sequential *** on multimodal sentiment analysis and disease prediction show that the proposed approaches perform favorably against state-of-the-art methods.

关键词： multimodal machine learning label distribution learning sentiment analysis disease prediction

Fei-Fei Li: Artificial Intelligence is on its way to reshape the world

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National Science Review 2017年第3期4卷 490-492页

作者： yi Zeng Ling Wang the Institute of Automation Chinese Academy of Sciences

Fei-Fei Li,a well-known scientist focusing on computer vision and Artificial Intelligence(AI),did not expect such zeal in China about *** her last visit to Beijing,the professor of Stanford University drew much attent... 详细信息

关键词： is it Artificial Intelligence is on its way to reshape the world Fei-Fei Li AI that have NLP NSR in been on

Forecasting of mechanical properties of covered electrode containing La/CeO_2 based on fuzzy neutral network

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Rare Metals 2018年第2期37卷 161-166页

作者： yi-Jun Xu Yong-Huan Guo Hui Fan School of Mechanical and Electrical Engineering Jiangsu Normal University

In order to improve the mechanical properties of deposited metal of ilmenite type welding electrode, CeO2/La rare earth elements were added into electrodes based on E4301 electrode, then electrodes were produced, test plates were welded, and mechanical properties were tested based on National Standards of China. For the sake of solving the problems of large amount of mechanical properties tests, long test cycle and high test cost during the conventional production process of electrode, a prediction model of the mechanical properties of deposited metal based on Takagi-Sugeno （T-S） fuzzy neural network was established. Mn, Si and C contents of medium manganese in electrode, CeO2, and La contents of electrode and welding speed were selected as input variables of the prediction model, and the tensile strength, lower yield strength, elongation, impact energy and hardness of de- posited metal were selected as output variables. Finally, predicting experiment was done under test samples, and results show that average relative prediction error of the tensile strength, lower yield strength, elongation and hardness are 0.91%, 2.57 %, 4.94 % and 1.94 %, respec- tively, which reach the need of actual production. The re- sults of prediction show that the mechanical properties of deposited metal of electrode containing rare earth can be forecasted accurately through material composition of electrode and welding parameters based on T-S fuzzy neural network model.

关键词： Covered electrode Rare earth element Fuzzyneural network Mechanical properties Prediction model

Ionic Liquid Assisted Imprint for Efficient and Stable Quasi-2D Perovskite Solar Cells with Controlled Phase Distribution

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Nano-Micro Letters 2023年第7期15卷 1-15页

作者： Haibin Peng Dengxue Li Zongcai Li Zhi Xing Xiaotian Hu ting Hu yiwang Chen Department of Polymer Materials and Engineering School of Physics and Materials ScienceNanchang University999 Xuefu AvenueNanchang 330031People’s Republic of China College of Chemistry and Chemical Engineering Institute of Polymers and Energy Chemistry(IPEC)Nanchang University999 Xuefu AvenueNanchang 330031People’s Republic of China National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal University99 Ziyang AvenueNanchang 330022People’s Republic of China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010People’s Republic of China

Although two-dimensional perovskite devices are highly stable,they also lead to a number of *** instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge *** this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite ***,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like *** this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior *** work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.

关键词： Imprint Two-dimensional perovskite Phase distribution Charge transfer Stability

Ni0.85 Se hexagonal nanosheets as an advanced conversion cathode for Mg secondary batteries

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Journal of Energy Chemistry 2020年第9期29卷 226-232,I0007页

作者： Dong Chen Jingwei Shen Xue Li Shun-an Cao ting Li Wei Luo Fei Xu Key Laboratory of Hydraulic Machinery Transients Ministry of EducationSchool of Power and Mechanical EngineeringWuhan UniversityWuhan 430072HubeiChina Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission Ministry of EducationCollege of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan 430074HubeiChina College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072HubeiChina

Mg secondary batteries are promising scalable secondary batteries for next-generation energy ***,Mg-storage cathode materials are greatly demanded to construct high-performance Mg *** conversion reaction provides plenty of cathode options,and strategy for cathode selection and performance optimization is of special *** this work,Ni0.85Se with nanostructures of dispersive hexagonal nanosheets(D-Ni0.85Se)and flower-like assembled nanosheets(F-Ni0.85Se)is synthesized and investigated as Mg-storage *** with F-Ni0.85Se,D-Ni0.85Se delivers a higher specific capacity of 168 mAh g^-1 at 50 mA g^-1 as well as better rate performance,owing to its faster Mg^2+-diffusion and lower resistance.D-Ni0.85Se also exhibits a superior cycling stability over *** investigation on mechanism indicates an evolution of Ni0.85Se towards NiSe with cycling,and the Mg-storage reaction occurs between NiSe and metallic Ni^*** present work demonstrates that advanced conversion-type Mg battery cathode materials could be constructed by soft selenide anions,and the electrochemical properties could be manipulated by rational material morphology optimization.

关键词： Mg secondary batteries Electrochemical conversion reaction Ni0.85Se Hexagonal nanosheets Diffusion kinetics

Application of wavelet support vector regression on SAR data de-noising

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Journal of Systems Engineering and Electronics 2011年第4期22卷 579-586页

作者： yi Lin Shaoming Zhang Jianqing Cai Nico Sneeuw Research Center of Remote Sensing and Spatial Technology Tongji University Shanghai 200092 P. R. China Institute of Geodesy University of Stuttgart D-70174 Stuttgart Germany

A new filtering method for SAR data de-noising using wavelet support vector regression （WSVR） is developed. On the basis of the grey scale distribution character of SAR imagery, the logarithmic SAR image as a noise polluted signal is taken and the noise model assumption in logarithmic domain with Gaussian noise and impact noise is proposed. Based on the better per- formance of support vector regression （SVR） for complex signal approximation and the wavelet for signal detail expression, the wavelet kernel function is chosen as support vector kernel func- tion. Then the logarithmic SAR image is regressed with WSVR. Furthermore the regression distance is used as a judgment index of the noise type. According to the judgment of noise type every pixel can be adaptively de-noised with different filters. Through an approximation experiment for a one-dimensional complex signal, the feasibility of SAR data regression based on WSVR is con- firmed. Afterward the SAR image is treated as a two-dimensional continuous signal and filtered by an SVR with wavelet kernel function. The results show that the method proposed here reduces the radar speckle noise effectively while maintaining edge features and details well.

关键词： synthetic aperture radar (SAR) support vector regres-sion (SVR) kernel function wavelet analysis function approximation.

Noether Theorem of Herglotz-Type for Nonconservative Hamilton Systems in Event Space

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Wuhan University Journal of Natural Sciences 2021年第5期26卷 376-382页

作者： ZHANG yi CAI Jinxiang College of Civil Engineering Suzhou University of Science and TechnologySuzhou 215011JiangsuChina

Focusing on the exploration of symmetry and conservation laws in event space, this paper studies Noether theorems of Herglotz-type for nonconservative Hamilton system. Herglotz’s generalized variational principle is first extended to event space,and on this basis, Hamilton equations of Herglotz-type in event space are derived. The invariance of Hamilton-Herglotz action is then studied by introducing infinitesimal transformation, and the definition of Herglotz-type Noether symmetry in event space is given, and its criterion is derived. Noether theorem of Herglotz-type and its inverse for event space nonconservative Hamilton system are proved. The application of Herglotz-type Noether theorem we obtained is introduced by taking Emden-Fowler equation and linearly damped oscillator as examples.

关键词： Herglotz’s generalized variational principle Noether theorem nonconservative Hamilton system event space

Subduction-zone peridotites and their records of crust-mantle interaction

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Science China Earth Sciences 2019年第7期62卷 1033-1052页

作者： Jianping ZHENG Qing XIONG yi ZHAO Wenbo LI School of Earth Sciences State Key Laboratory of Geological Processes and Mineral ResourcesChina University of Geosciences

Subduction is the core process of plate tectonics. The mantle wedge in subduction-zone systems represents a key tectonic unit, playing a significant role in material cycling and energy exchange between Earth's layers. This study summarizes research progresses in terms of subduction-related peridotite massifs, including supra-subduction zone(SSZ) ophiolites and mantle-wedge-type(MWT) orogenic peridotites. We also provide the relevant key scientific questions that need be solved in the future. The mantle sections of SSZ ophiolites and MWT orogenic peridotites represent the mantle fragments from oceanic and continental lithosphere in subduction zones, respectively. They are essential targets to study the crust-mantle interaction in subduction zones. The nature of this interaction is the complex chemical exchanges between the subducting slab and the mantle wedge under the major control of physical processes. The SSZ ophiolites can record melt/fluid-rock interaction, metamorphism,deformation, concentration of metallogenic elements and material exchange between crust and mantle, during the stages from the generation of oceanic lithosphere at spreading centers to the initiation, development, maturation and ending of oceanic subduction at continental margins. The MWT orogenic peridotites reveal the history of strong metamorphism and deformation during subduction, the multiple melt/fluid metasomatism(including silicatic melts, carbonatitic melts and silicate-bearing C-HO fluids/supercritical fluids), and the complex cycling of crust-mantle materials, during the subduction/collision and exhumation of continental plates. In order to further reveal the crust-mantle interaction using subduction-zone peridotites, it is necessary to utilize high-spatial-resolution and high-precision techniques to constrain the complex chemical metasomatism, metamorphism,deformation at micro scales, and to reveal their connections with spatial-temporal evolution in macro-scale tectonics.

关键词： Subduction zone Ophiolite Orogenic peridotite Mantle wedge Metasomatism Crust-mantle interaction