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Communications on Applied Mathematics and Computation 2024年第1期6卷 311-324页

作者： bo dong Wei Wang Department of Mathematics University of Massachusetts DartmouthNorth DartmouthMA02747USA Department of Mathematics and Statistics Florida International UniversityMiamiFL33199USA

In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(dong et *** J Sci Comput 66:321–345,2016;dong and Wang in J Comput Appl Math 380:1–11,2020)for a one-dimensional stationary Schrödinger *** work showed that penalty parameters were required to be positive in error analysis,but the methods with zero penalty parameters worked fine in numerical simulations on coarse *** this work,by performing extensive numerical experiments,we discover that zero penalty parameters lead to resonance errors in the multiscale DG methods,and taking positive penalty parameters can effectively reduce resonance errors and make the matrix in the global linear system have better condition numbers.

关键词： Discontinuous Galerkin(DG)method Multiscale method Resonance errors One-dimensional Schrödinger equation

Linear-fitting-based recursive filtering for nonlinear systems under encoding-decoding mechanism

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Science China(Information Sciences) 2024年第5期67卷 183-196页

作者： bo JIANG Hongli dong Zhiwei GAO yuxuan SHEN Fan yANG Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Sanya Offshore Oil & Gas Research Institute Northeast Petroleum University School of Electrical & Information Engineering Northeast Petroleum University

This paper deals with a recursive filtering problem for a class of discrete time-varying nonlinear networked systems with the encoding-decoding mechanism. The linear fitting method is introduced to handle the nonlinearity. An encoding-decoding mechanism is constructed to describe the data transmission process in wireless communication networks(WCNs). To be specific, the measurement outputs are mapped by a quantizer to unique codewords for transmission in WCNs. Then, the codewords are decoded by the decoder to recover the measurement outputs which are sent to the filter. The processing/encoding delay and network delay have been considered. Firstly, on the premise that the upper bound of the filtering error covariance is minimum, the appropriate filtering gain is calculated. Then, the mean square exponential boundedness of the filtering error is analyzed. Finally, two simulation examples are presented to verify the effectiveness of the proposed algorithm.

关键词： encoding-decoding mechanism uniform quantizer linear fitting networked systems recursive filtering

Anomaly-Resistant Decentralized State Estimation Under Minimum Error Entropy With Fiducial Points for Wide-Area Power Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 74-87页

作者： bogang Qu Zidong Wang bo Shen Hongli dong Hongjian Liu the College of Automation Engineering Shanghai University of Electric PowerShanghai 200090China IEEE the Department of Computer Science Brunel University LondonUxbridgeMiddiesex UB83PHUK the College of Information Science and Technology Donghua UniversityShanghai 200051 the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of EducationShanghai 201620China the Artificial Intelligence Energy Research Institute Northeast Petroleum UniversityDaqing 163318 the Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast PetroleumDaqing 163318 the Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanya 572024China the Key Laboratory of Advanced Perception and Intelligent Control of High-End Equipment Ministry of EducationAnhui Polytechnic UniversityWuhu 2410000 the School of Mathematics and Physics Anhui Polytechnic UniversityWuhu 241000China

This paper investigates the anomaly-resistant decentralized state estimation(SE) problem for a class of wide-area power systems which are divided into several non-overlapping areas connected through transmission lines. Two classes of measurements(i.e., local measurements and edge measurements) are obtained, respectively, from the individual area and the transmission lines. A decentralized state estimator, whose performance is resistant against measurement with anomalies, is designed based on the minimum error entropy with fiducial points(MEEF) criterion. Specifically, 1) An augmented model, which incorporates the local prediction and local measurement, is developed by resorting to the unscented transformation approach and the statistical linearization approach;2) Using the augmented model, an MEEF-based cost function is designed that reflects the local prediction errors of the state and the measurement;and 3) The local estimate is first obtained by minimizing the MEEF-based cost function through a fixed-point iteration and then updated by using the edge measuring information. Finally, simulation experiments with three scenarios are carried out on the IEEE 14-bus system to illustrate the validity of the proposed anomaly-resistant decentralized SE scheme.

关键词： Decentralized state estimation(SE) measurements with anomalies minimum error entropy unscented Kalman filter wide-area power systems

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Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： yan-li Xin Zhi-ying Gao bo Tian Qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Customized Convolutional Neural Network for Accurate Detection of Deep Fake Images in Video Collections

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Computers, Materials & Continua 2024年第5期79卷 1995-2014页

作者： Dmitry Gura bo dong Duaa Mehiar Nidal Al Said Department of Cadastre and Geoengineering Kuban State Technological UniversityKrasnodar350072Russian Federation Department of Geodesy Kuban State Agrarian UniversityKrasnodar350072Russian Federation School of Innovation and Entrepreneurship Liaoning UniversityLiaoning110031China Department of IT Middle East UniversityAmman11831Jordan College of Mass Communication Ajman UniversityP.O Box 346AjmanUnited Arab Emirates

The motivation for this study is that the quality of deep fakes is constantly improving,which leads to the need to develop new methods for their *** proposed Customized Convolutional Neural Network method involves extracting structured data from video frames using facial landmark detection,which is then used as input to the *** customized Convolutional Neural Network method is the date augmented-based CNN model to generate‘fake data’or‘fake images’.This study was carried out using Python and its *** used 242 films from the dataset gathered by the Deep Fake Detection Challenge,of which 199 were made up and the remaining 53 were *** seconds were allotted for each *** were 318 videos used in all,199 of which were fake and 119 of which were *** proposedmethod achieved a testing accuracy of 91.47%,loss of 0.342,and AUC score of 0.92,outperforming two alternative approaches,CNN and ***,our method succeeded in greater accuracy than contemporary models such as XceptionNet,Meso-4,EfficientNet-bo,MesoInception-4,VGG-16,and *** novelty of this investigation is the development of a new Convolutional Neural Network(CNN)learning model that can accurately detect deep fake face photos.

关键词： Deep fake detection video analysis convolutional neural network machine learning video dataset collection facial landmark prediction accuracy models

Macrocyclic peptides:up-and-coming weapons to combat antimicrobial resistance

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1786-1787页

作者： Wen-Jing Wang Xiang-Min dong Guo-bo L Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuanChina Key Laboratory of Drug Targeting and Drug Delivery System of Ministry of Education Department of Medicinal ChemistryWest China School of PharmacySichuan UniversityChengduSichuanChina

Recently,two companion papers published in Nature reported a first-in-class tethered macrocyclic peptide antibiotic targeting carbapenem-resistant ***(CRAB)and unveiled their unique antibacterial mechanism,which invol... 详细信息

关键词： outer macrocyclic Macrocyclic

Investigation of non-uniform leading-edge tubercles in compressor cascade:Based on multi-objective optimization and data mining

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Chinese Journal of Aeronautics 2024年第7期37卷 134-152页

作者： Jiezhong dong Wuli CHU Haoguang ZHANG bo LUO Tianyuan JI Ziyun ZHANG School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Corner stall receives noticeable attention in the aeroengine field as an important phenomenon in highly-load ***-uniform leading-edge tubercles,as an effective method to delay stall,are introduced into the *** this paper,the shape of leading-edge tubercles was controlled by a third-order Fourier *** judge corner stall,a more precise stall indicator for compressor cascade with flow control methods was ***,the total kinetic energy of the secondary flow at large incidence was adopted as a parameter for stall evaluation to save computing *** results of multiobjective optimization reveal that the loss coefficient exhibited negligible variation at design incidence,while the total kinetic energy of secondary flow showed a significant reduction at large incidence,resulting in a substantial increase in stall *** the optimal profiling cases,the stall incidencewas delayed from 7.9°to 11.6°.The major purpose of the research is to provide proper design guidelines for nonuniformleading-edge tubercles and uncover the flow controlmechanisms of leading-edge ***,the geometric features that meet different optimization objectives were extracted through geometric analysis near the Pareto Front and through Self-OrganizingMap(SOM)dataminingmethods in the optimization ***,flow field analysis reveals the flow control mechanism of leading-edge *** convex-concave-convex structure at the 0%-70%blade height region can form two branches of leading-edge vortex pairs that are opposite in the rotation direction to the passage *** two branches of leading-edge vortex pairs mixed with the leading-edge separation vortex to form two stronger mixed vortices,which can effectively suppress the development of passage vortex and delay stall incidence.

关键词： Corner stall Non-uniform leading-edge tubercles Stall indicator Stall evaluation parameter Mixed vortex

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Intelligent representation method of image flatness for cold rolled strip

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Journal of Iron and Steel Research International 2024年第5期31卷 1177-1195页

作者： yang-huan Xu dong-cheng Wang Hong-min Liu bo-wei Duan National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710018ShaanxiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina

Real flatness images are the bases for flatness detection based on machine vision of cold rolled *** characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is *** interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be *** this basis,the concept of image flatness is proposed for the first *** image flatness representation(IFAR)model is established on the basis of an autoencoder with a new *** optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation ***,interpretability analysis of the representation factors is carried out,and the difference and physical meaning of the representation factors for image flatness with different categories are *** flatness with new defect morphologies(bilateral quarter waves and large middle waves)that are not present in the original dataset are generated by modifying the representation factors of the no wave ***,the SLD and IFAR models are used to detect and represent all the real flatness images on the test *** average processing time for a single image is 11.42 ms,which is suitable for industrial *** research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： Cold rolled strip Image flatness Location detection Representation learning bottleneck layer

The mechanisms of thermal solidification agent promoting steam diversion in heavy oil reservoirs

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Petroleum Science 2024年第3期21卷 1902-1914页

作者： Zhan-Xi Pang Qian-Hui Wang Qiang Meng bo Wang dong Liu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Liaohe Oilfield Institute CNPC ChinaPanjin124000LiaoningChina Henan Oilfield Institute Sinopec ChinaNanyang473400HenanChina Tianjin Branch of China National Offshore Oil Company(CNOOC)Ltd. Tianjin300452China

At high cycles of steam huff&puff,oil distribution in reservoirs becomes stronger heterogeneity due to steam *** solidification agent can be used to solve this *** solution is a lowviscosity liquid at normal temperature,but it can be solidified above 80℃.The plugging degree is up to 99%at 250℃.The sweep efficiency reaches 59.2%,which is 7.3%higher than pure steam *** addition,simultaneous injection of viscosity reducer and/or nitrogen foams can further enhance oil *** mechanism of this technology depends on its strong plugging ability,which changes the flowing pattern of steam to effectively mobilize remaining *** reducer and nitrogen foams further expand the sweep range and extends the effective ***,thermal solidification agent can plug steam channeling paths and adjust steam flowing direction to significantly enhance oil recovery at high cycles of steam huff&puff.

关键词： Heavy oil reservoir Steam huff&puff Steam channeling Steam diversion Plugging performance Mechanism analysis

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Memory-enhanced text style transfer with dynamic style learning and calibration

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Science China(Information Sciences) 2024年第4期67卷 181-196页

作者： Fuqiang LIN yiping SONG Zhiliang TIAN Wangqun CHEN Diwen dong bo LIU College of Computer Science and Technology National University of Defense Technology Department of Computer Science and Engineering The Hong Kong University of Science and Technology Strategic Assessments and Consultation Institute Academy of Military Sciences

Text style transfer aims to rephrase a sentence to match the desired style while retaining the original content. As a controllable text generation task, mainstream approaches use content-independent style embedding as control variables to guide stylistic generation. Nonetheless, stylistic properties are contextsensitive even under the same style. For example, “delicious” and “helpful” convey positive sentiments,although they are more likely to describe food and people, respectively. Therefore, desired style signals must vary with the content. To this end, we propose a memory-enhanced transfer method, which learns fine-grained style representation concerning content to assist transfer. Rather than employing static style embedding or latent variables, our method abstracts linguistic characteristics from training corpora and memorizes subdivided content with the corresponding style representations. The style signal is dynamically retrieved from memory using the content as a query, providing a more expressive and flexible latent style space. To address the imbalance between quantity and quality in different content, we further introduce a calibration method to augment memory construction by modeling the relationship between candidate *** results obtained using three benchmark datasets confirm the superior performance of our model compared to competitive approaches. The evaluation metrics and case study also indicate that our model can generate diverse stylistic phrases matching context.

关键词： style transfer memory-enhanced method text generation deep learning text representation