检索结果-内蒙古大学图书馆

IEEE Transactions on Artificial Intelligence 2024年第8期5卷 3858-3871页

作者： Yang, Jing Lu, Ting Zhu, Youjie Hefei University of Technology Intelligent Interconnected Systems Laboratory of Anhui Province Hefei230009 China Hefei University of Technology School of Computer Science and Information Engineering Hefei230009 China

Discovering causal relationships from a large amount of observational data is an important research direction in data mining. To address the challenges of discovering and constructing causal networks on nonlinear and high-dimensional data, this article proposes a new structural learning algorithm called spatial coordinates based (SCB). The SCB algorithm effectively discovers causal networks from large scale nonlinear data. In this article, we make three main contributions. Firstly, based on the Hilbert-Schmidt independence criterion (HSIC), we propose new independence test coefficients: spatial coordinate (SC) coefficient and conditional spatial coordinate (CSC) coefficient. We also prove that the statistical distribution of the CSC coefficient follows a standard normal distribution. Secondly, using the statistical distribution of the CSC coefficient, we redefine the correlation of variables and combine it with local learning to propose the SCB algorithm. Finally, we demonstrate the effectiveness of the algorithm through experiments on data generated from various nonlinear function dependencies. Compared to existing algorithms, the causal network models constructed using the SCB algorithm exhibit significant improvements in accuracy and time performance. The effectiveness of the proposed method is further validated on real power plant data. © 2020 IEEE.

关键词： Additive noise

来源：评论

学校读者我要写书评

暂无评论

Dual-channel tunable multipolarization adapted terahertz spatiotemporal vortices generating device

引用

Photonics Research 2025年第5期13卷 1408-1418页

作者： FANGZE DENG KE MA YUMENG MA XIANG HOU ZHIHUA HAN YUCHAO LI KEKE CHENG YANSHENG SHAO CHENGLONG WANG MENG LIU HUIYUN ZHANG AND YUPING ZHANG Qingdao Key Laboratory of Terahertz Technology College of Electronic and Information Engineering Shandong University of Science and Technology

Spatiotemporal optical vortices (STOVs) exhibit characteristics of transverse orbital angular momentum (OAM)that is perpendicular to the direction of pulse propagation, indicating significant potential for diverse applications. In this study, we employ vanadium dioxide and photonic crystal plates to design tunable transreflective dual-channel terahertz (THz) spatiotemporal vortex generation devices that possess multipolarization adaptability. In the reflection channel, we achieve active tunability of the topological dark lines by utilizing circularly polarized light, based on the topological dark phenomenon, and observe variations in the number of singularities across the parameter space from different observational perspectives. In the transmission channel, we generate independent vortex singularities using linearly polarized light. This multifunctional terahertz device offers a novel approach for the generation and active tuning of spatiotemporal vortices.

关键词： Optical vortices Phase shift Photonic crystals Pulse propagation Quantum vortices Spatial light modulators

来源：评论

学校读者我要写书评

暂无评论

MATD3-Based End-Edge Collaborative Resource Optimization for NOMA-Assisted Industrial Wireless Networks

引用

Computers, Materials & Continua 2025年第2期82卷 3203-3222页

作者： Ru Hao Chi Xu Jing Liu College of Information Engineering Shenyang University of Chemical TechnologyShenyang110142China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang110016China

Non-orthogonal multiple access (NOMA) technology has recently been widely integrated into multi-access edge computing (MEC) to support task offloading in industrial wireless networks (IWNs) with limited radio resources. This paper minimizes the system overhead regarding task processing delay and energy consumption for the IWN with hybrid NOMA and orthogonal multiple access (OMA) schemes. Specifically, we formulate the system overhead minimization (SOM) problem by considering the limited computation and communication resources and NOMA efficiency. To solve the complex mixed-integer nonconvex problem, we combine the multi-agent twin delayed deep deterministic policy gradient (MATD3) and convex optimization, namely MATD3-CO, for iterative optimization. Specifically, we first decouple SOM into two sub-problems, i.e., joint sub-channel allocation and task offloading sub-problem, and computation resource allocation sub-problem. Then, we propose MATD3 to optimize the sub-channel allocation and task offloading ratio, and employ the convex optimization to allocate the computation resource with a closed-form expression derived by the Karush-Kuhn-Tucker (KKT) conditions. The solution is obtained by iteratively solving these two sub-problems. The experimental results indicate that the MATD3-CO scheme, when compared to the benchmark schemes, significantly decreases system overhead with respect to both delay and energy consumption.

关键词： Industrial wireless networks(IWNs) multi-access edge computing(MEC) non-orthogonal multiple access(NOMA) task offloading resource allocation

来源：评论

学校读者我要写书评

暂无评论

H_(2)O_(2) treatment boosts activity of NiFe layered double hydroxide for electro-catalytic oxidation of urea

引用

Journal of Environmental sciences 2023年第7期129卷 152-160页

作者： Jinshan Wei Jin Wang Xiaoming Sun College of Materials Science and Engineering Key Laboratory of Optoelectronic Devices and SystemsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China

Urea oxidation reaction(UOR)provides a method for hydrogen production besides wastewater treatment,but the current limited catalytic activity has prevented the ***,we develop a novel H_(2)O_(2) treatment strategy for tailoring the surface oxygen ligand of NiFe-layered double hydroxides(NiFe-LDH).The sample after H_(2)O_(2) treatment(NiFeOLDH)shows significant enhancement on UOR efficiency,with the potential of 1.37 V(RHE)to reach a current density of 10 mA/cm^(2).The boost is attributed to the richness adsorption O ligand on NiFeO-LDH as revealed by XPS and Raman *** calculation indicates formation of two possible types of oxygen ligands:adsorbed oxygen on the surface and exposed from hydroxyl group,lowered the desorption energy of CO_(2) product,which lead to the lowered onset *** strategy is further extended to NiFe-LDH nano sheet on Ni foam to reach a higher current density of 440 mA/cm^(2) of UOR at 1.8 V(RHE).The facile surface O ligand manipulation is also expected to give chance to many other electro-catalytic oxidations.

关键词： NiFe-LDH Urea oxidation reaction H_(2)O_(2)treatment Electro-catalysis Hydrogen production

来源：评论

学校读者我要写书评

暂无评论

A spawning particle filter for defocused moving target detection in GNSS-based passive radar

引用

Journal of systems engineering and Electronics 2023年第5期34卷 1085-1100页

作者： ZENG Hongcheng DENG Jiadong WANG Pengbo ZHOU Xinkai YANG Wei CHEN Jie School of Electronic and Information Engineering Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Space Microwave China Academy of Space TechnologyXi’an 710000China

Global Navigation Satellite System(GNSS)-based passive radar(GBPR)has been widely used in remote sensing ***,for moving target detection(MTD),the quadratic phase error(QPE)introduced by the non-cooperative target motion is usually difficult to be compensated,as the low power level of the GBPR echo signal renders the estimation of the Doppler rate less ***,the moving target in GBPR image is usually defocused,which aggravates the difficulty of target detection even *** this paper,a spawning particle filter(SPF)is proposed for defocused ***,the measurement model and the likelihood ratio function(LRF)of the defocused point-like target image are ***,a spawning particle set is generated for subsequent target detection,with reference to traditional particles in particle filter(PF)as their *** that,based on the PF estimator,the SPF algorithm and its sequential Monte Carlo(SMC)implementation are proposed with a novel amplitude estimation method to decrease the target state ***,the effectiveness of the proposed SPF is demonstrated by numerical simulations and pre-liminary experimental results,showing that the target range and Doppler can be estimated accurately.

关键词： Global Navigation Satellite System(GNSS)-based passive radar(GBPR) defocused target moving target detec-tion(MTD) likelihood ratio function(LRF) spawning particle fil-ter(SPF)

来源：评论

学校读者我要写书评

暂无评论

Design high-performance narrowband emitters for blue light-emitting diodes through manipulating resonance structure of aromatic heterocycles

引用

science China Chemistry 2025年第6期68卷 2652-2659页

作者： Yue Yu Lei Xu Wenle Tan Yuyu Pan Jiyin Xiao Bohan Wang Guangjun Tian Yuguang Ma Lei Ying Institute of Polymer Optoelectronic Materials and Devices Guangdong Basic Research Center of Excellence for Energy and Information Polymer Materials State Key Laboratory of Luminescent Materials and Devices South China University of Technology School of Petrochemical Engineering Shenyang University of Technology Key Laboratory for Microstructural Material Physics of Hebei Province School of Science Yanshan University

Narrowband light-emitting materials play critical roles in improving the color gamut and energy consumption of electroluminescence. Herein we demonstrated that by regulating the ground state resonance structure form of emitters with polycyclic aromatic heterocycles, the high-energy vibration of the C–C bond can be effectively suppressed, resulting in narrow emission like classical cyanine dyes. The designed compounds consist of twist and planar conformation, while having differences in the orientation of the positioning electron-donating(nitrogen) and electron-accepting(carbonyl) groups in the polycyclic aromatic hydrocarbon skeleton. The resulting compound Ac-Ph-Ac with a dominated zwitterionic resonance structure exhibits a relatively wide electroluminescent profile with the full width at half maximum(FWHM) of 42 nm and moderate device performance. In contrast, the “soliton transition” of 2Ac Ph based on the cyanine limit character effectively suppresses C–C stretching vibration in the polycyclic aromatic heterocycle skeleton, leading to a narrow electroluminescent profile with FWHM of 30 nm(0.16 e V)associated with an impressively high external quantum efficiency of 28.52%, which is among the highest efficiencies of so far reported non-sensitized organic light-emitting diodes.

关键词： narrowband emission organic light-emitting diodes aromatic heterocycles resonance structure cyanine limit

来源：评论

学校读者我要写书评

暂无评论

Two efficient beamforming methods for hybrid IRS-aided AF relay wireless networks

引用

science China(information sciences) 2025年第4期68卷 363-379页

作者： Xuehui WANG Qingbo LI Wen ZHU Feng SHU Mengxing HUANG Fuhui ZHOU Riqing CHEN Cunhua PAN Yongpeng WU Jiangzhou WANG School of Mathematics and Statistics Hainan Normal University Key Laboratory of Data Science and Smart Education Ministry of Education Hainan Normal University School of Information and Communication Engineering Hainan University Collaborative Innovation Center of Information Technology Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Digital Fujian Institute of Big Data for Agriculture Fujian Agriculture and Forestry University National Mobile Communications Research Laboratory Southeast University Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University School of Engineering University of Kent

Owing to its ability to mitigate the double-fading effect by amplifying the reflected signal, the active intelligent reflecting surface(IRS) has garnered significant attention. In this paper, an amplify-and-forward(AF) relay network assisted by a hybrid IRS consisting of both passive and active units is developed. A signal-to-noise ratio(SNR) maximization problem is formulated, where the AF relay beamforming matrix and the hybrid IRS reflecting coefficient matrices for two-time slots need to be optimized. To address the SNR maximization problem, this paper proposes both a high-performance(HP) method and a low-complexity(LC) method. The HP method is based on the semidefinite relaxation and fractional programming(SDR-FP)algorithm, with rank-1 solutions obtained through Gaussian randomization. For the LC method, the amplification coefficient of each active IRS element is assumed to be equal. The SNR maximization problem is then addressed using the whitening filter,generalized power iteration, and generalized Rayleigh-Ritz(WF-GPI-GRR) approach. Simulation results show that compared with the benchmarks, such as the passive IRS-aided AF relay network, the proposed HP-SDR-FP and WF-GPI-GRR methods achieve significant rate improvements. In particular, the HP-SDR-FP and WF-GPI-GRR methods yield more than a 135.0%rate gain when the transmit power Ps of the source is 10 dBm. Furthermore, the proposed HP-SDR-FP method outperforms the WF-GPI-GRR method in terms of rate performance.

关键词： double-fading intelligent reflecting surface active elements passive elements hybrid IRS AF relay

来源：评论

学校读者我要写书评

暂无评论

MLP-Mixer based Masked Auto encoders Are Effective, Explainable and Robust for Time Series Anomaly Detection 51st

MLP-Mixer based Masked Auto encoders Are Effective, Explaina...

引用

51st International Conference on Very Large Data Bases, VLDB 2025

作者： Tang, Qideng Dai, Chaofan Wu, Yahui Zhou, Haohao National Key Laboratory of Information Systems Engineering National University of Defense Technology China National University of Defense Technology China

Time series anomaly detection remains one of the most active research areas in data mining due to its wide range of real-world applications. In recent years, numerous deep learning-based methods have been proposed for this task. However, deep learning-based methods fail to detect subsequence anomalies with long durations, lack explain ability, and are vulnerable to training set contamination. This paper addresses these issues by proposing a novel deep learning framework for effective, explainable, and robust time series anomaly detection. Our framework, MMA, incorporates the MLP-Mixer backbone with a Masked Auto encoder-based anomaly detection approach to allow for a significantly larger input window size (10 to 20 times larger than the input window sizes of current models). This larger input window enables our model to detect challenging subsequence anomalies. Meanwhile, a contrast learning module is proposed to aid in detecting subtle anomalies that fail to be identified by residual errors. Furthermore, a dynamic anomaly filtering method is introduced to mitigate the impact of subsequence anomalies on the reconstruction of surrounding normal regions to reduce false alarms. Extensive experiments on univariate and multivariate time series datasets demonstrate that our proposed framework significantly outperforms state-of-the-art methods across rigorous evaluation metrics. Additionally, MMA has a strong ability to reconstruct potential normal patterns in anomalous regions, providing high levels of explain ability. Moreover, MMA demonstrates high robustness to various types of training set pollution. © 2025, VLDB Endowment, All rights reserved.

关键词： Mixers (machinery)

来源：评论

学校读者我要写书评

暂无评论

Multiple effects of polydopamine nanoparticles on Cu^(2+)-mediated Alzheimer's β-amyloid aggregation

引用

Chinese Journal of Chemical engineering 2023年第2期54卷 144-152页

作者： Xueqing Chen Weiqun Gao Yan Sun Xiaoyan Dong Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Deposition of β-amyloid protein(Aβ) is the main hallmark of Alzheimer's disease(AD), and it has been well recognized that Cu^(2+)-mediated Aβ aggregation plays a crucial role in AD pathological ***^(2+)binding to Aβ can promote the production of reactive oxygen species(ROS) through Fenton-like reactions and produce more toxic Aβ-Cu^(2+)species under Cu^(2+)stimulation. Thus, the development of nanomaterials that can inhibit Cu^(2+)-mediated Aβ aggregation and degrade Aβ-Cu^(2+)complexes is considered an effective strategy for the prevention and treatment of AD. In this study, polydopamine nanoparticles(PDA NPs) were prepared and the results reveal that PDA NPs potently inhibit Cu^(2+)-mediated Aβaggregation and effectively reduce the formation of Aβ-Cu^(2+)complexes. In vitro experiments show that PDA NPs efficiently eliminate ROS generation catalyzed by Cu^(2+)or Aβ-Cu^(2+)complexes, thus rescuing cultured cells by reducing intracellular ROS levels. More importantly, PDA NPs can depolymerize Aβ-Cu^(2+)complexes, and the degradation of Aβ-Cu^(2+)complexes is promoted by near-infrared light irradiation due to their high photothermal conversion ability. In vivo studies reveal that PDA NPs significantly reduce the deposition of Aβ plaques in the presence of Cu^(2+)and extend the lifespan of AD nematodes from 11 to 14 d. Thus, the PDA NPs developed herein are multifunctional against Cu^(2+)-mediated Aβ aggregation for the potential prevention and treatment of AD.

关键词： Protein Aggregation Nanoparticles Photothermal therapy Reactive oxygen species Cu^(2+)chelator

来源：评论

学校读者我要写书评

暂无评论

Facile purification and immobilization of organophosphorus hydrolase on protein-inorganic hybrid phosphate nanosheets

引用

Chinese Journal of Chemical engineering 2023年第4期56卷 119-125页

作者： Zhenfu Wang Jie Gao Qinghong Shi Xiaoyan Dong Yan Sun Department of Biochemical Engineering School of Chemical Engineering and Technology and Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education)Tianjin UniversityTianjin 300350China

Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis ***,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical *** this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated ***-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free ***,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,*** results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.

关键词： Calcium phosphate nanocrystal(CaPs) Biomimetic mineralization Organophosphorus hydrolase(OPH) Oriented immobilization Hydrolysis Methyl parathion

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：