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Random Low Patch⁃rank Method for Interpolation of Regularly Missing Traces

Journal of Harbin Institute of Technology(New Series) 2020年第3期27卷 205-216页

作者： Jianwei ma Department of mathematics Center of Geophysics and Artificial Intelligence LaboratoryHarbin Institute of TechnologyHarbin 150001China

Assuming seismic data in a suitable domain is low rank while missing traces or noises increase the rank of the data matrix,the rank⁃reduced methods have been applied successfully for seismic interpolation and denoising.These rank⁃reduced methods mainly include Cadzow reconstruction that uses eigen decomposition of the Hankel matrix in the f⁃x(frequency⁃spatial)domain,and nuclear⁃norm minimization(NNM)based on rigorous optimization theory on matrix completion(MC).In this paper,a low patch⁃rank MC is proposed with a random⁃overlapped texture⁃patch mapping for interpolation of regularly missing traces in a three⁃dimensional(3D)seismic volume.The random overlap plays a simple but important role to make the low⁃rank method effective for aliased data.It shifts the regular column missing of data matrix to random point missing in the mapped matrix,where the missing data increase the rank thus the classic low⁃rank MC theory works.Unlike the Hankel matrix based rank⁃reduced method,the proposed method does not assume a superposition of linear events,but assumes the data have repeated texture patterns.Such data lead to a low⁃rank matrix after the proposed texture⁃patch mapping.Thus the methods can interpolate the waveforms with varying dips in space.A fast low⁃rank factorization method and an orthogonal rank⁃one matrix pursuit method are applied to solve the presented interpolation model.The former avoids the singular value decomposition(SVD)computation and the latter only needs to compute the large singular values during iterations.The two fast algorithms are suitable for large⁃scale data.Simple averaging realizations of several results from different random⁃overlapped texture⁃patch mappings can further increase the reconstructed signal⁃to⁃noise ratio(SNR).Examples on synthetic data and field data are provided to show successful performance of the presented method.

关键词： seismic data interpolation low⁃rank method random patch geophysics

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3D Microdisplacement Monitoring of Large Aircraft Assembly with Automated In Situ Calibration

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Engineering 2022年第12期19卷 105-116页

作者： Zhenyuan Jia Bing Liang Wei Liu Kun Liu Jianwei ma School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

Three-dimensional(3D)microdisplacement monitoring plays a crucial role in the assembly of large aircraft.This paper presents a broadly applicable high-precision online 3D microdisplacement monitoring method and system based on proximity sensors as well as a corresponding in situ calibration method,which can be applied under various extreme working conditions encountered in the aircraft assembly process,such as compact and obstructed spaces.A 3D monitoring model is first established to achieve 3D microdisplacement monitoring based only on the one-dimensional distances measured by proximity sensors,which concerns the extrinsic sensor parameters,such as the probe base point(PBP)and the unit displacement vector(UDV).Then,a calibration method is employed to obtain these extrinsic parameters with high precision by combining spatial transformation principles and weighted optimization.Finally,calibration and monitoring experiments performed for a tailplane assembly process are reported.The calibration precision for the PBP is better than±10 lm in the X and Y directions and±2 lm in the Z direction,and the calibration precision for the UDV is better than 0.07°.Moreover,the accuracy of the 3D microdisplacement monitoring system can reach±15 lm.In general,this paper provides new insights into the modeling and calibration of 3D microdisplacement monitoring based on proximity sensors and a precise,efficient,and low-cost technical means for performing related measurements in compact spaces during the aircraft assembly process.

关键词： Aircraft manufacture Assembly Calibration Condition monitoring Displacement measurement

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On-line batch production of ferrate with an chemical method and its potential application for greywater recycling with Al(Ⅲ) salt

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Journal of Environmental Sciences 2017年第2期29卷 1-7页

作者： Yarui Song Bin Men Dongsheng Wang Jianwei ma Northeast Petroleum University Institute of Civil Engineering and Construction State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Ferrate（Ⅵ ） salt is an oxidant and coagulant for water and wastewater treatment. It is considered as a possible alternative method in greywater treatment. However, challenges have existed in putting ferrate（Ⅵ ） technology into full-scale practice in water and wastewater treatment due to the instability of ferrate solution and high production cost of solid ferrate products. This study demonstrated a new approach of greywater treatment with on-line batch production of Fe（Ⅵ ） to which Fe（Ⅲ ） salt was oxidized at a weak acidity solution. A series of experiments were conducted to investigate the effect of Fe（Ⅵ ） on light greywater（total organic carbon（TOC） = 19.5 mg/L） and dark greywater（TOC = 55 mg/L）treatment under different conditions with varying p H and Fe（Ⅵ ） doses. In addition, the combination use of Fe（Ⅵ ） and Al（Ⅲ ） salts was proved to be more efficient than using the Fe（Ⅵ ） salts alone at greywater recycling. The optimum dosage of Fe（Ⅵ ）/Al（Ⅲ ） salts was 25/25 mg/L for light greywater, 90/60 mg/L for dark greywater, respectively. The TOC values of both light greywater and dark greywater were reduced to less than 3 mg/L with the dosages.The cost for treating greywater was 0.06–0.2 $/ton at ferrate（Ⅵ ） dosage of 25–90 mg/L and0.008–0.024 $/ton at AlCl3 dosage of 25–60 mg/L. The full operating cost needs further assessment before the Fe（Ⅵ ）/Al（Ⅲ ） technology could be implemented in greywater treatment.

关键词： On-line Ferrate Coagulation Oxidation Greywater AlCl3

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Modeling and analytical calculation of road damage coefficient considering tire pressure and damping of vehicles

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第6期12卷 17-32页

作者： Jianwei ma Wenlong Wang Department of Automobile Engineering Xingtai Polytechnic College Xingtai 054035 HebeiP.R.China

The road damage coefficientβis a significant indicator to estimate the degree of the road damage caused by vehicles.The existing calculation method ofβis not convenient for the engineering application.To effectively evaluate the damage degree and facilitate the engineering application,this paper studied the simple and reliable analytical calculation method ofβ.Firstly,a dynamic model of the vehicle–road system was created.The tire pressure and the tire damping were considered in the model.Moreover,the relationship between the tire vertical stiffness and the tire pressure is approximated as a linear function.Secondly,based on the dynamic model,according to the definition ofβ,a concise analytical formula ofβwas derived and verified by numerical simulations.The relative errors of the analytical calculation results are all less than 0.1%.Thirdly,the influences of the tire pressure p,the damping ratioξs of the suspension system,and the damping ratioξt of the wheel system onβwere analyzed.Moreover,based on the analytical formula ofβ,a mathematical model of the optimal damping matching for the suspension system was established and a case study was also given.The research results show that the larger the tire pressure p,the larger the value ofβis.For each p,there is an optimal damping ratioξs.If the tire damping is ignored,it will lead to the design error forξs.Finally,some important conclusions were drawn.The analytical formula ofβand the conclusions can provide valuable references for the analysis of the road damage and the initial design of vehicle suspensions.

关键词： Vehicles road damage coefficient analytical formula tire pressure damping matching

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EScope:Effective Event Validation for IoT Systems Based on State Correlation

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Big Data Mining and Analytics 2023年第2期6卷 218-233页

作者： Jian mao Xiaohe Xu Qixiao Lin Liran ma jianwei Liu School of Cyber Science and Technology Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China Department of Computer Science Texas Christian UniversityFort WorthTX 76129USA

Typical Internet of Things(IoT)systems are event-driven platforms,in which smart sensing devices sense or subscribe to events(device state changes),and react according to the preconfigured trigger-action logic,as known as,automation rules.“Events”are essential elements to perform automatic control in an IoT system.However,events are not always trustworthy.Sensing fake event notifications injected by attackers(called event spoofing attack)can trigger sensitive actions through automation rules without involving authorized users.Existing solutions verify events via“event fingerprints”extracted by surrounding sensors.However,if a system has homogeneous sensors that have strong correlations among them,traditional threshold-based methods may cause information redundancy and noise amplification,consequently,decreasing the checking accuracy.Aiming at this,in this paper,we propose“EScope”,an effective event validation approach to check the authenticity of system events based on device state correlation.EScope selects informative and representative sensors using an Neural-Network-based(NN-based)sensor selection component and extracts a verification sensor set for event validation.We evaluate our approach using an existing dataset provided by Peeves.The experiment results demonstrate that EScope achieves an average 67%sensor amount reduction on 22 events compared with the existing work,and increases the event spoofing detection accuracy.

关键词： Internet of Things(IoT) event spoofing event fingerprint correlation analysis

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Genetic variation of wood tracheid traits and their relationships with growth and wood density in clones of Pinus tabuliformis

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Journal of Forestry Research 2018年第4期29卷 1014-1023页

作者： Fangqun Ouyang Jianwei ma Sanping An Junhui Wang Yuhui Weng State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of Forestry Chinese Academy of Forestry Beijing 100083 People's Republic of China Research Institute of Forestry of Xiaolong Mountain Tianshui 741020 Gansu People's Republic of China Arthur Temple College of Forestry and Agriculture Stephen F. Austin State University Nacogdoches TX 75962 USA

To improve wood quality for pulpwood industries, it is important to examine not only wood density but also its components, especially tracheid characteristics. We studied genetic variations in the following tracheid traits by earlywood （EW） and latewood （LW）： tracheid length （TL）, double wall thickness （WT）, radial lumen diameter （R_D1）, tangential lumen diameter （T_D1）, radial central diameter （R_D2）, and tangential central diameter （T_D2）. We also studied the relationship with the following growth traits： diameter at breast height （DBH）, height （H）, crown breadth south-north axis （NSC）, crown breadth east-west axis （EWC）, ring width （RW）, latewood percentage （LWP）, and wood density （WD）. All sample materials were collected from a 33-year old clonal seed orchard of Pinus tabuliformis Carr. Genetic variation among clones was moderate for all tracheid traits, 9.49-26.03%. Clones significantly affected WT, R_D1, R_D2, T_D1, T_D2, and the two ratios WT/R_D1 and TL/T_D2 in EW but had no effects in LW. Clones significantly affected TL in LW but had no effects in EW. H2/C was higher in LW （0.50） than in EW （0.20） for TL, while H 2/C was higher in EW （0.27-0.46） for other tracheid traits and the two ratios （TL/T_D2 and WT/R_D1） than in EW （0.06-0.22）. WD and TL were significantly positively correlated, but WT and TL were negatively correlated both at individual and clone levels; all tracheid diameters and the four ratio values （EW_WT/ R_D1, LW WT/R_D1, EW_TL/T_D2 and LW_TL/ T_D2）, were strongly positively correlated with DBH, H, NSC, WEC and RW, and strongly negatively correlated with WD both at individual and clone levels. The most important variables for predicting WD were LW_TL, EW_WT and R_D1 in both EW and LW （r2= 0.22）. Selecting the top 10% of the clones by DBH would improve DBH growth by 12.19% （wood density was reduced by 0.14%） and produced similar responses between EW and LW for all tracheid traits： a reduction of 0.94 and 3.69% in tracheid length and increases in tracheid diameters （from 0.36 to 5.24%） and d

关键词： Pinus tabuliformis Clone Tracheid traits Wood density Genetic variation Correlation coefficient

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QoS-Aware Cloud Service Optimization Algorithm in Cloud manufacturing Environment

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Intelligent Automation & Soft Computing 2023年第8期37卷 1499-1512页

作者： Wenlong ma Youhong Xu jianwei Zheng Sadaqat ur Rehman School of Information Engineering Quzhou College of TechnologyQuzhou324000China School of Computer Science and Technology Zhejiang University of TechnologyHangzhou310023China Department of Natural and Computing Science University of AberdeenScotlandAberdeenAB243FXUK

In a cloud manufacturing environment with abundant functionally equivalent cloud services,users naturally desire the highest-quality service(s).Thus,a comprehensive measurement of quality of service(QoS)is needed.Opti-mizing the plethora of cloud services has thus become a top priority.Cloud ser-vice optimization is negatively affected by untrusted QoS data,which are inevitably provided by some users.To resolve these problems,this paper proposes a QoS-aware cloud service optimization model and establishes QoS-information awareness and quantiﬁcation mechanisms.Untrusted data are assessed by an information correction method.The weights discovered by the variable precision Rough Set,which mined the evaluation indicators from historical data,providing a comprehensive performance ranking of service quality.The manufacturing cloud service optimization algorithm thus provides a quantitative reference for service selection.In experimental simulations,this method recommended the optimal services that met users’needs,and effectively reduced the impact of dis-honest users on the selection results.

关键词： Cloud manufacturing quality of service optimization algorithm rough set

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Why Has China's Current Account Balance Converged after the Global Financial Crisis?

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China & World Economy 2021年第1期29卷 109-129页

作者： jianwei Xu Panpan Yang Guangrong ma School of Economics and Business Administration Beijing Normal UniversityChina Senior Research Fellow Institute of World Economics and PoliticsChinese Academy of Social SciencesChina China Financial Policy Research Center School of FinanceRenmin University of China

China's current account surplus declined significantly from its peak of nearly 10 percentof GDP in 2007 to less than 1 percent in 2018.The new pattern offered fresh evidencefor our understanding of China's current account dynamics.In this paper,we used flowof funds data to gauge its underlying driving forces.Specifically,by employing indexdecomposition analysis,we decomposed the current account from the perspective ofsavings and investment into three sectors:the household,corporate,and governmentsectors.We found that the decline in China's current account ratio was first driven bycyclical factors,i.***.weak corporate saving growth induced by the economic slump in2009 as well as the following massive corporate investment bolstered by the governmentstimulus plan.However,such cyclical factors quickly subsided,and the subsequentcurrent account balance reduction was later supported by structural factors,i.***.household savings declined enduringly and the Chinese government switched to a moreexpansionary fiscal policy.There are three possible explanations for the structuralmovement:reduced precautionary saving due to higher social security coverage ratio,lower corporate profits as a result of economic slowdown,and a twin deficit due to thegovernment's more relaxed fiscal stance.The new facts,however,were not consistent withother current account theories focusing on long-term aspects of the saving-investmentaccount puzzle,especially those relating to China's special demographic characteristics.

关键词： current account flow of funds accounts investment saving

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Electrospun chitosan nanofibers for wound healing application

Engineered Regeneration

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Engineered Regeneration 2021年第1期2卷 82-90页

作者： Congjing Cui Shibin Sun Shaohua Wu Shaojuan Chen Jianwei ma Fang Zhou College of Textiles and Clothing Qingdao UniversityQingdao266071ShandongChina

Electrospun nanofibers have been considered as relatively ideal material system for the design and construction of surgical wound dressings in the past few decades.Although there are lots of other biopolymers employed for electrospinning,chitosan is one of the most important biopolymers for the fabrication of electrospun nanofibers,due to its nontoxic,antibacterial,biocompatible as well as biodegradable properties.Electrospun chitosan nanofibers with random or aligned fiber structure can further be cross-linked by physical,chemical and ionic crosslinking methods.The as-crosslinked electrospun chitosan nanofibrous membranes possess enhanced wet stability,improved mechanical property and good biocompatibility,which are necessary for wound healing application.The present work reviews the recent studies on the design and development of electrospun chitosan nanofibers and their applications for wound healing,such as antibacterial materials,hemostatic dressings,angiogenesis and immune regulation.

关键词： Electrospinning Chitosan Nanofibers Wound healing

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马建伟同病异治乙肝感染者膜性肾病医案

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中医药临床杂志 2017年第3期29卷 353-355页

作者：王珊马建伟北京空军总医院北京海淀区100142 北京中医药大学北京朝阳区100029

膜性肾病（MN）是以病理形态学命名的一组肾小球疾病，主要表现为肾小球基底膜增厚且伴有上皮细胞下免疫复合物沉积，免疫荧光以免疫球蛋白IgG和补体C3呈细颗粒状沿肾小球毛细血管壁沉积为主。临床多以肾病综合征为主要表现。

关键词：乙肝膜性肾病非典型膜性肾病马建伟同病异治医案

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