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Journal of Computer Science & Technology 2021年第2期36卷 361-374页

作者： Xia-An Bi Zhao-xu Xing rui-hui xu Xi Hu College of Information Science and Engineering Hunan Normal UniversityChangsha 410006China Hunan Provincial Key Laboratory of Intelligent Computing and Language Information Processing Hunan Normal UniversityChangsha 410006China

As an emerging research field of brain science,multimodal data fusion analysis has attracted broader attention in the study of complex brain diseases such as Parkinson's disease(PD).However,current studies primarily lie with detecting the association among different modal data and reducing data *** data mining method after fusion and the overall analysis framework are *** this study,we propose a weighted random forest(WRF)model as the feature screening *** interactions between genes and brain regions are detected as input multimodal fusion features by the correlation analysis *** implement sample classification and optimal feature selection based on WRF,and construct a multimodal analysis framework for exploring the pathogenic factors of *** experimental results in Parkinson's Progression Markers Initiative(PPMI)database show that WRF performs better compared with some advanced methods,and the brain regions and genes related to PD are *** fusion of multi-modal data can improve the classification of PD patients and detect the pathogenic factors more comprehensively,which provides a novel perspective for the diagnosis and research of *** also show the great potential of WRF to perform the multimodal data fusion analysis of other brain diseases.

关键词： multimodal fusion feature Parkinson's disease pathogenic factor detection sample classification weighted random forest model

A real-time intelligent lithology identification method based on a dynamic felling strategy weighted random forest algorithm

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Petroleum Science 2024年第2期21卷 1135-1148页

作者： Tie Yan rui xu Shi-hui Sun Zhao-Kai Hou Jin-Yu Feng School of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya572025HainanChina

Real-time intelligent lithology identification while drilling is vital to realizing downhole closed-loop drilling. The complex and changeable geological environment in the drilling makes lithology identification face many challenges. This paper studies the problems of difficult feature information extraction,low precision of thin-layer identification and limited applicability of the model in intelligent lithologic identification. The author tries to improve the comprehensive performance of the lithology identification model from three aspects: data feature extraction, class balance, and model design. A new real-time intelligent lithology identification model of dynamic felling strategy weighted random forest algorithm(DFW-RF) is proposed. According to the feature selection results, gamma ray and 2 MHz phase resistivity are the logging while drilling(LWD) parameters that significantly influence lithology identification. The comprehensive performance of the DFW-RF lithology identification model has been verified in the application of 3 wells in different areas. By comparing the prediction results of five typical lithology identification algorithms, the DFW-RF model has a higher lithology identification accuracy rate and F1 score. This model improves the identification accuracy of thin-layer lithology and is effective and feasible in different geological environments. The DFW-RF model plays a truly efficient role in the realtime intelligent identification of lithologic information in closed-loop drilling and has greater applicability, which is worthy of being widely used in logging interpretation.

关键词： Intelligent drilling Closed-loop drilling Lithology identification Random forest algorithm Feature extraction

Multicolor circularly polarized phosphorescence of axially chiral binuclear platinum(Ⅱ) complexes

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Science China Chemistry 2024年第11期67卷 3757-3766页

作者： Jintong Song rui Zeng hui Xiao Hailiang Ni Zong-Xiang xu Haifeng Xiang College of Chemistry and Materials Science Sichuan Normal University Department of Chemistry Southern University of Science and Technology College of Chemistry Sichuan University

D-A charge transfer, including through-bond charge transfer and through-space charge transfer between two different electron donors（D） and electron acceptors（A）, is a fundamental and powerful tool to tune the optical properties of organic dyes. Herein,we demonstrate a unique strategy to tune phosphorescence and circularly polarized luminescence properties of axially chiral binuclear Pt（Ⅱ） complexes through long-range charge transfer, even though these molecules have two totally identical segments on either side of the chiral core. The presence of axial chirality would break not only the symmetry of molecular structure and π-conjugation system but also the symmetry of charge distribution for long-range charge transfer. These binaphthyl-based Pt（Ⅱ）complexes bearing coordinated atoms far away from chiral axis exhibit no Pt-Pt interactions but colorful concentrationdependent phosphorescence with quantum yield up to 86.4% and could be applied as emitters in highly efficient solutionprocessed organic light-emitting diodes to achieve luminance, luminance efficiency, power efficiency, external quantum efficiency, and asymmetry factor up to 8.94 × 10～3cd m-2, 41.9 cd A-1, 18.8 lm W-1, 12.6% and 2.98 × 10-3, respectively. Therefore,the present work affords a new and simple way to utilize the inherently asymmetric advantage of chirality for the design of D-Abased organic dyes.

关键词： Pt(II) complexes organic light-emitting diodes circularly polarized phosphorescence axial chirality

Stromal thrombospondin 1 suppresses angiogenesis in oral submucous fibrosis

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International Journal of Oral Science 2024年第1期16卷 163-172页

作者： Xiao Yang hui Zhao rui Li Yang Chen Zhi xu Zhengjun Shang State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyWuhan UniversityWuhanChina Department of Oral and Maxillofacial-Head and Neck Oncology School of Stomatology–Hospital of StomatologyWuhan UniversityWuhanChina Department of Stomatology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

A decline in mucosal vascularity is a histological hallmark of oral submucous fibrosis (OSF), a premalignant disease that is largely induced by betel quid chewing. However, the lack of available models has challenged studies of angiogenesis in OSF. Here, we found that the expression of thrombospondin 1 (THBS1), an endogenous angiostatic protein, was elevated in the stroma of tissues with OSF. Using a fibroblast-attached organoid (FAO) model, the overexpression of THBS1 in OSF was stably recapitulated in vitro. In the FAO model,treatment with arecoline, a major pathogenic component in areca nuts, enhanced the secretion of transforming growth factor (TGF)-β1 by epithelial cells, which then promoted the expression of THBS1 in fibroblasts. Furthermore, human umbilical vein endothelial cells (HUVECs)were incorporated into the FAO to mimic the vascularized component. Overexpression of THBS1 in fibroblasts drastically suppressed the sprouting ability of endothelial cells in vascularized FAOs (v FAOs). Consistently, treatment with arecoline reduced the expression of CD31in v FAOs, and this effect was attenuated when the endothelial cells were preincubated with neutralizing antibody of CD36, a receptor of THBS1. Finally, in an arecoline-induced rat OSF model, THBS1 inhibition alleviated collagen deposition and the decline in vascularity in vivo. Overall, we exploited an assembled organoid model to study OSF pathogenesis and provide a rationale for targeting THBS1.

关键词： angiogenesis elevated endogenous

Security defense strategy algorithm for Internet of Things based on deep reinforcement learning

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High-Confidence Computing 2024年第1期4卷 7-13页

作者： xuecai Feng Jikai Han rui Zhang Shuo xu hui Xia School of Computer Science and Technology Ocean University of ChinaQingdao 266100China

Currently,important privacy data of the Internet of Things(IoT)face extremely high risks of *** persistently engage in continuous attacks on terminal devices to obtain private data of crucial *** significant progress has been made in recent years in deep reinforcement learning defense strategies,most defense methods still face problems such as low defense resource allocation efficiency and insufficient defense coordination *** solve the above problems,this paper constructs a novel adversarial security scenario and proposes a security game model that integrates defense resource allocation and patrol *** the above game model,this paper designs a deep reinforcement learning algorithm named SDSA to calculate its security defense *** calculates the allocation strategy of the best patrolling strategy that is most suitable for the defender by searching the policy on a multi-dimensional discrete action space,and enables multiple defense agents to cooperate efficiently by training a multi-intelligent Dueling Double Deep Q-Network(D3QN)with prioritized experience ***,the experimental results show that the SDSA-learned security defense strategy can provide a feasible and effective security protection strategy for defenders against attacks compared to the MADDPG and OptGradFP methods.

关键词： Internet of Things Cyber security Deep reinforcement learning Game theory

Hybrid improper ferroelectricity and phase transition behavior of Li_(2)Nd_(2)Ti_(3)O_(10)ceramics with A-site ordered triple-layer Ruddlesden-Popper structure

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Journal of Materiomics 2024年第1期10卷 145-153页

作者： Bi hui Zhang Diming xu rui Ze Guo Lu Liu Xiao Qiang Liu Xiang Ming Chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310058China Key Laboratory of Multifunctional Materials and Structures Ministry of EducationSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an710049China

Hybrid improper ferroelectricity has been extensively reported through theoretical prediction and experimental investigation in the oxides with Ruddlesden-Popper(R-P)***,the experimentally reported ferroelectric materials based on triple-layer R-P structures are rare,and the weak ferroelectricity impedes its practical *** the present work,the single-phase Li_(2)Nd_(2)Ti_(3)O_(10)ceramics with A-site cation ordered triple-layer R-P structure was obtained by spark plasma sintering technique,and the crystal structure of P2_(1)ab symmetry was revealed by neutron powder diffraction and transmission electron microscope ***,the switchable ferroelectricity in Li_(2)Nd_(2)Ti_(3)O_(10)ceramics has been observed at room temperature,and the saturated polarization-electric field hysteresis loop was obtained with P_(r)=0.4μC/cm^(2)under the electric field of 250 kV/*** phase transition behavior of Li_(2)Nd_(2)Ti_(3)O_(10)oxides was revealed by the temperature-dependence Raman and dielectric spectra combined with the piezoelectric property.

关键词： Hybrid improper ferroelectricity A-site ordered Ruddlesden-Popper structure Phase transition behavior

Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： rui Wen Shao Jun Wei Wu Zheng Xing Wang hui xu Han Qing Yang Qiang Cheng Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng Cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

Thyristor-inserted MMC Sub-module Topology with DC Fault Blocking Capability

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2221-2229页

作者： Cheng Peng rui Li xu Cai Key Laboratory of Control of Power Transmission and Conversion Shanghai Jiao Tong UniversityMinistry of EducationShanghai Jiao Tong UniversityShanghai 200240China.

Modular multilevel converter(MMC)is increasingly being applied to high voltage direct current(HVDC)***,dc short circuit situations restrain the application of a conventional half bridge MMC *** this paper,a new sub-module topology with inserted thyristor can help the MMC system clear a dc side *** states and devices voltage stress of the proposed topology are analyzed and the conduction loss comparison between the proposed topology with several existing topologies with dc fault blocking capability is carried *** show the proposed topology is superior to other topologies in terms of conduction loss while using the same voltage rating ***,compared with traditional half bridge topology,only thyristors and diodes are added in the proposed ***,cost of the proposed topology can be lower than conventional hybrid MMC *** last,the fault blocking capability of the proposed topology is verified in the simulation.

关键词： Fault current limiting high voltage direct current(HVDC)transmission modular multilevel converter(MMC)

Image Recognition Model of Fraudulent Websites Based on Image Leader Decision and Inception-V3 Transfer Learning

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China Communications 2024年第1期21卷 215-227页

作者： Shengli Zhou Cheng xu rui xu Weijie Ding Chao Chen Xiaoyang xu Information Department of Zhejiang Police College Hangzhou 310053China Hangzhou Dianzi University Hangzhou 310018China Big Data Laboratory of Zhejiang Police College Hangzhou 310053China Hangzhou Public Security Bureau Hangzhou 310002China

The fraudulent website image is a vital information carrier for telecom *** efficient and precise recognition of fraudulent website images is critical to combating and dealing with fraudulent *** research on image recognition of fraudulent websites is mainly carried out at the level of image feature extraction and similarity study,which have such disadvantages as difficulty in obtaining image data,insufficient image analysis,and single identification *** study develops a model based on the entropy method for image leader decision and Inception-v3 transfer learning to address these *** data processing part of the model uses a breadth search crawler to capture the image ***,the information in the images is evaluated with the entropy method,image weights are assigned,and the image leader is *** model training and prediction,the transfer learning of the Inception-v3 model is introduced into image recognition of fraudulent *** selected image leaders to train the model,multiple types of fraudulent websites are identified with high *** experiment proves that this model has a superior accuracy in recognizing images on fraudulent websites compared to other current models.

关键词： fraudulent website image leaders telecom fraud transfer learning

Recent advances in Fe-N-C-and Co-N-C-based materials as bifunctional electrocatalysts for oxygen reduction and oxygen evolution

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Science China Chemistry 2024年第4期67卷 1137-1160页

作者： hui-Min xu Hong-rui Zhu Chen-Jin Huang Zhi-Jie Zhang Ting-Yu Shuai Qi-Ni Zhan Gao-Ren Li College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Fe-nitrogen-carbon(Fe-N-C)-and Co-nitrogen-carbon(Co-N-C)-based electrocatalysts have been widely concerned because of their high OER/ORR activity,low metal cost,and simple *** exploration of Fe-N-C and Co-N-C single atombased catalysts with high activity and stability to overcome the slow kinetics of oxygen reduction and oxygen evolution reactions is also the key to the development of efficient electrolytic water,fuel cells,and rechargeable metal-air ***-N-C and Co-N-C single atom-based electrocatalysts have the advantages of a high utilization rate of metal atoms and high electrocatalytic activity,and are ideal catalysts for promoting electrochemical energy conversion and *** general principles of designing Fe-N-C and Co-N-C single atom-based electrocatalysts are reviewed in this ***,the strategies to improve the bifunctional catalytic activity and stability are ***,the challenges and prospects of Fe-N-C and Co-N-C single atom-based catalysts are well *** review will provide a reference for the directed optimization of Fe-N-C and Co-N-C single atom-based catalysts.

关键词： Fe-N-C Co-N-C single atom bifunctional oxygen electrocatalysts