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Multiplicative Derivations on Rank-s Matrices for Relatively Small s

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代数集刊:英文版 2023年第2期30卷 281-292页

作者： Xiaowei Xu Baochuan Xie Yanhua Wang Zhibing Zhao College of Mathematics Jilin UniversityChangchun 130012China School of Mathematics Shanghai Key Laboratory of Financial Information Technology Shanghai University of Finance and EconomicsShanghai 200433China School of Mathematical Sciences Anhui UniversityHefei 230601China

In this paper,we describe multiplicative derivations on the set of all rank-s matrices of Mn(K)over a field K with a relatively small integer s.Concretely,for fixed integers n,s satisfying 1≤s≤n/2 and n≥2,we prove that if a map d:Mn(K)→Mn(K)satisfiesδ(xy)=δ(x)y+xδ(y)for any two rank-s matrices,y∈Mn(K),then there exists a derivation D of Mn(K)such thatδ(x)=D(x)for each rank-k matrix a E Mn(K)with 0≤k≤s.As an application,we prove that a multiplicative derivation on a special subset of Mn(K)must be a derivation.

关键词： multiplicative derivations rank-s matrices singular matrices

Research on Detection Method of Interest Flooding Attack on Content Centric Network

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Computers, Materials & Continua 2020年第8期64卷 1075-1089页

作者： Yabin xu Ting xu Xiaowei Xu Beijing Key Laboratory of Internet Culture and Digital Dissemination Research Beijing100101China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Information Science and Technology UniversityBeijing100101China School of Computer Beijing Information Science&Technology UniversityBeijing100101China Department of Information Science University of Arkansas at Little RockLittle Rock72204USA

To improve the attack detection capability of content centric network(CCN),we propose a detection method of interest flooding attack(IFA)making use of the feature of self-similarity of traffic and the information entropy of content name of interest packet.On the one hand,taking advantage of the characteristics of self-similarity is very sensitive to traffic changes,calculating the Hurst index of the traffic,to identify initial IFA attacks.On the other hand,according to the randomness of user requests,calculating the information entropy of content name of the interest packets,to detect the severity of the IFA attack,is.Finally,based on the above two aspects,we use the bilateral detection method based on non-parametric CUSUM algorithm to judge the possible attack behavior in CCN.The experimental results show that flooding attack detection method proposed for CCN can not only detect the attack behavior at the early stage of attack in CCN,but also is more accurate and effective than other methods.

关键词： CCN interest flooding attack self-similar feature information entropy bilateral detection method

Research on Privacy Disclosure Detection Method in Social Networks Based on Multi-Dimensional Deep Learning

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Computers, Materials & Continua 2020年第1期62卷 137-155页

作者： Yabin xu xuyang Meng Yangyang Li Xiaowei Xu School of Computer Beijing Information Science&Technology UniversityBeijing100101China Beijing Key Laboratory of Internet Culture and Digital Dissemination Research Beijing100101China Innovation Center China Academy of Electronics and Information TechnologyBeijing100041China Department of Information Science University of Arkansas at Little RockLittle Rock72204USA

In order to effectively detect the privacy that may be leaked through social networks and avoid unnecessary harm to users,this paper takes microblog as the research object to study the detection of privacy disclosure in social networks.First,we perform fast privacy leak detection on the currently published text based on the fastText model.In the case that the text to be published contains certain private information,we fully consider the aggregation effect of the private information leaked by different channels,and establish a convolution neural network model based on multi-dimensional features(MF-CNN)to detect privacy disclosure comprehensively and accurately.The experimental results show that the proposed method has a higher accuracy of privacy disclosure detection and can meet the real-time requirements of detection.

关键词： Social networks privacy disclosure detection multi-dimensional features text classification convolutional neural network

Non-contact optical characterization of negative pressure in hydrogel voids and microchannels

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Frontiers of Optoelectronics 2022年第1期15卷 113-120页

作者： Shihao xu xiaowei Liu Zehua Yu Kang Liu MOE Key Laboratory of Hydrodynamic Transients School of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

Negative pressure in water under tension,as a thermodynamic non-equilibrium state,has facilitated the emergence of inno-vative technologies on microfluidics,desalination,and thermal management.However,the lack of a simple and accurate method to measure negative pressure hinders further in-depth understanding of the properties of water in such a state.In this work,we propose a non-contact optical method to quantify the negative pressure in micron-sized water voids of a hydrogel film based on the microscale mechanical deformation of the hydrogel itself.We tested three groups of hydrogel samples with different negative pressure inside,and the obtained results fit well with the theoretical prediction.Furthermore,we demonstrated that this method can characterize the distribution of negative pressure,and can thus provide the possibility of investigation of the flow behavior of water in negative pressure.These results prove this technique to be a promising approach to characterization of water under tension and for investigation of its properties under negative pressure.

关键词： Hydrogel Negative pressure Non-contact Optical

Armendariz Property of k[x,y]Modulo Monomial Ideals

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Communications in Mathematical Research 2022年第3期38卷 421-429页

作者： Ying Guo Xiankun Du Xiaowei Xu Department of Mathematics Jilin UniversityChangchunP.R.China.

In this paper,we give equivalent conditions for the factor rings of the polynomial ring k[x,y]modulo monomial ideals to be Armendariz rings,where k is a field.For an ideal I with 2 or 3 monomial generators,or n homogeneous monomial generators,such that k[x,y]/I is an Armendariz ring,we characterize the minimal generator set G(I)of I.

关键词： Armendariz ring polynomial ring monomial ideal

Drug target discovery by magnetic nanoparticles coupled mass spectrometry

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Journal of Pharmaceutical Analysis 2021年第1期11卷 122-127页

作者： Dandan Xia Baoling Liu Xiaowei Xu Ya Ding Qiuling Zheng Department of Pharmaceutical Analysis School of PharmacyChina Pharmaceutical UniversityNanjing210009China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing210009China Key Laboratory of Drug Metabolism and Pharmacokinetics China Pharmaceutical UniversityNanjing210009China

Drug target discovery is the basis of drug screening.It elucidates the cause of disease and the mechanism of drug action,which is the essential of drug innovation.Target discovery performed in biological systems is complicated as proteins are in low abundance and endogenous compounds may interfere with drug binding.Therefore,methods to track drug-target interactions in biological matrices are urgently required.In this work,a Fe_(3)O_(4) nanoparticle-based approach was developed for drug-target screening in biofluids.A known ligand-protein complex was selected as a principle-to-proof example to validate the feasibility.After incubation in cell lysates,ligand-modified Fe_(3)O_(4) nanoparticles bound to the target protein and formed complexes that were separated from the lysates by a magnet for further analysis.The large surface-to-volume ratio of the nanoparticles provides more active sites for the modification of chemical drugs.It enhances the opportunity for ligand-protein interactions,which is beneficial for capturing target proteins,especially for those with low abundance.Additionally,a one-step magnetic separation simplifies the pre-processing of ligand-protein complexes,so it effectively reduces the endogenous interference.Therefore,the present nanoparticle-based approach has the potential to be used for drug target screening in biological systems.

关键词： Drug-target discovery Nanoparticle Mass spectrometry

A Prediction Method of Fracture Toughness of Nickel-Based Superalloys

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Computer Systems Science & Engineering 2022年第7期42卷 121-132页

作者： Yabin xu Lulu Cui Xiaowei Xu School of Computer Beijing Information Science and Technology UniversityBeijing100101China Department of Information Science University of Arkansas at Little RockArkansas72204USA

Fracture toughness plays a vital role in damage tolerance design of materials and assessment of structural integrity.To solve these problems of com-plexity,time-consuming,and low accuracy in obtaining the fracture toughness value of nickel-based superalloys through experiments.A combination prediction model is proposed based on the principle of materials genome engineering,the fracture toughness values of nickel-based superalloys at different temperatures,and different compositions can be predicted based on the existing experimental data.First,to solve the problem of insufﬁcient feature extraction based on manual experience,the Deep Belief Network(DBN)is used to extract features,and an attention mechanism module is introduced.To achieve the purpose of strengthen-ing the important features,an attention weight is assigned to each feature accord-ing to the importance of the feature.Then,the feature vectors obtained by the DBN module based on the Attention mechanism(A-DBN)are spliced with the original features.Thus,the prediction accuracy of the model is improved by extracting high-order combined features and low-order linear features between input and output data.Finally,the spliced feature vectors are put into the Support Vector Regression(SVR)model to further improve the regression prediction abil-ity of the model.The results of the contrast experiment show that the model can effectively improve the prediction accuracy of the fracture toughness value of nickel-based superalloys.

关键词： Nickel-based superalloys fracture toughness materials genome engineering deep belief network attention mechanism support vector regression

Fourth-Order Structure-Preserving Method for the Conservative Allen-Cahn Equation

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Advances in Applied Mathematics and Mechanics 2023年第1期15卷 159-181页

作者： xiaowei Chen xu Qian Songhe Song Department of Mathematics National University of Defense TechnologyChangshaHunan 410073China

We propose a class of up to fourth-order maximum-principle-preserving and mass-conserving schemes for the conservative Allen-Cahn equation equipped with a non-local Lagrange multiplier.Based on the second-order finite-difference semidiscretization in the spatial direction,the integrating factor Runge-Kutta schemes are applied in the temporal direction.Theoretical analysis indicates that the proposed schemes conserve mass and preserve the maximum principle under reasonable time step-size restriction,which is independent of the space step size.Finally,the theoretical analysis is verified by several numerical examples.

关键词： Maximum-principle-preserving mass-conserving scheme the conservative AllenCahn equation

Risk factors of major intraoperative bleeding and postoperative bleeding associated with endoscopic submucosal dissection for gastric neoplasms

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Chinese Medical Journal 2022年第3期135卷 309-316页

作者： Shanshan xu Ningli Chai xiaowei Tang Enqiang Linghu Shasha Wang Nankai University School of Medicine Nankai UniversityTianjin 300071China Department of Gastroenterology and Hepatology The First Medical Center of Chinese People's Liberation Army General HospitalBeijing 100853China

Background:Endoscopic resection bleeding(ERB)classification was proposed by the authors’team to evaluate the severity of intraoperative bleeding(IB)during endoscopic submucosal dissection(ESD).This study aimed to evaluate the application of ERB classification and to analyze the risk factors of major IB(MIB)and postoperative bleeding(PB)associated with ESD for gastric neoplastic lesions.Methods:We retrospectively enrolled a total of 1334 patients who underwent ESD between November 2006 and September 2019 at The First Medical Center of Chinese People’s Liberation Army General Hospital.All patients were divided into the non-MIB group(including ERB-0,ERB-controlled 1[ERB-c1],and ERB-c2)and the MIB group(including ERB-c3 and ERB-uncontrolled[ERB-unc])according to the ERB classification.Risk factors of major MIB and risk factors of PB were analyzed using a logistic regression model.Results:Among the 1334 patients,773(57.95%)had ERB-0,477(35.76%)had ERB-c1,77(5.77%)had ERB-c2,7(0.52%)had ERB-c3,and no patients had ERB-unc.The rate of PB in patients with IB classifications of ERB-0,ERB-c1,ERB-c2,and ERB-c3 were 2.20%(17/773),3.35%(16/477),9.09%(7/77),and 2/7,respectively.In multivariate analysis,proximal location(odds ratio[OR]:1.488;95%confidence interval[CI]:1.045-3.645;P=0.047)was the only significant risk factor of MIB.Chronic kidney disease(CKD)(OR:7.844;95%CI:1.637-37.583;P=0.010)and MIB(ERB-c3)(OR:13.932;95%CI:2.585-74.794;P=0.002)were independent risk factors of PB.Conclusions:Proximal location of lesions was a significant risk factor of MIB.Additionally,CKD and MIB(ERB-c3)were independent risk factors of PB.More attention should be paid to these high-risk patients for MIB and PB.

关键词： Endoscopic resection bleeding classification Endoscopic submucosal dissection Gastric neoplasms