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High-Order Decoupled and Bound Preserving Local Discontinuous Galerkin Methods for a Class of Chemotaxis Models

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Communications on Applied Mathematics and Computation 2024年第1期6卷 372-398页

作者： wei zheng Yan Xu School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina

In this paper,we explore bound preserving and high-order accurate local discontinuous Galerkin(LDG)schemes to solve a class of chemotaxis models,including the classical Keller-Segel(KS)model and two other density-dependent problems.We use the convex splitting method,the variant energy quadratization method,and the scalar auxiliary variable method coupled with the LDG method to construct first-order temporal accurate schemes based on the gradient flow structure of the models.These semi-implicit schemes are decoupled,energy stable,and can be extended to high accuracy schemes using the semi-implicit spectral deferred correction method.Many bound preserving DG discretizations are only worked on explicit time integration methods and are difficult to get high-order accuracy.To overcome these difficulties,we use the Lagrange multipliers to enforce the implicit or semi-implicit LDG schemes to satisfy the bound constraints at each time step.This bound preserving limiter results in the Karush-Kuhn-Tucker condition,which can be solved by an efficient active set semi-smooth Newton method.Various numerical experiments illustrate the high-order accuracy and the effect of bound preserving.

关键词： Chemotaxis models Local discontinuous Galerkin(LDG)scheme Convex splitting method Variant energy quadratization method Scalar auxiliary variable method Spectral deferred correction method

Improving the spaceborne GNSS-R altimetric precision based on the novel multilayer feedforward neural network weighted joint prediction model

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Defence Technology（防务技术） 2024年第2期32卷 271-284页

作者： Yiwen Zhang wei zheng Zongqiang Liu Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China China Academy of Aerospace Science and Innovation Beijing 100176China State Key Laboratory of Space-Ground Integrated Information Technology Beijing Institute of Satellite Information EngineeringBeijing 100194China

Global navigation satellite system-reflection(GNSS-R)sea surface altimetry based on satellite constellation platforms has become a new research direction and inevitable trend,which can meet the altimetric precision at the global scale required for underwater navigation.At present,there are still research gaps for GNSS-R altimetry under this mode,and its altimetric capability cannot be specifically assessed.Therefore,GNSS-R satellite constellations that meet the global altimetry needs to be designed.Meanwhile,the matching precision prediction model needs to be established to quantitatively predict the GNSS-R constellation altimetric capability.Firstly,the GNSS-R constellations altimetric precision under different configuration parameters is calculated,and the mechanism of the influence of orbital altitude,orbital inclination,number of satellites and simulation period on the precision is analyzed,and a new multilayer feedforward neural network weighted joint prediction model is established.Secondly,the fit of the prediction model is verified and the performance capability of the model is tested by calculating the R2 value of the model as 0.9972 and the root mean square error(RMSE)as 0.0022,which indicates that the prediction capability of the model is excellent.Finally,using the novel multilayer feedforward neural network weighted joint prediction model,and considering the research results and realistic costs,it is proposed that when the constellation is set to an orbital altitude of 500 km,orbital inclination of 75and the number of satellites is 6,the altimetry precision can reach 0.0732 m within one year simulation period,which can meet the requirements of underwater navigation precision,and thus can provide a reference basis for subsequent research on spaceborne GNSS-R sea surface altimetry.

关键词： GNSS-R satellite constellations Sea surface altimetric precision Underwater navigation Multilayer feedforward neural network

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Improving path planning efficiency for underwater gravity-aided navigation based on a new depth sorting fast search algorithm

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Defence Technology（防务技术） 2024年第2期32卷 285-296页

作者： Xiaocong Zhou wei zheng Zhaowei Li Panlong Wu Yongjin Sun School of Automation Nanjing University of Science and TechnologyNanjing210094China China Academy of Aerospace Science and Innovation Beijing100176China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing100094China School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin150001China

This study focuses on the improvement of path planning efficiency for underwater gravity-aided navigation.Firstly,a Depth Sorting Fast Search(DSFS)algorithm was proposed to improve the planning speed of the Quick Rapidly-exploring Random Trees*(Q-RRT*)algorithm.A cost inequality relationship between an ancestor and its descendants was derived,and the ancestors were filtered accordingly.Secondly,the underwater gravity-aided navigation path planning system was designed based on the DSFS algorithm,taking into account the fitness,safety,and asymptotic optimality of the routes,according to the gravity suitability distribution of the navigation space.Finally,experimental comparisons of the computing performance of the ChooseParent procedure,the Rewire procedure,and the combination of the two procedures for Q-RRT*and DSFS were conducted under the same planning environment and parameter conditions,respectively.The results showed that the computational efficiency of the DSFS algorithm was improved by about 1.2 times compared with the Q-RRT*algorithm while ensuring correct computational results.

关键词： Depth Sorting Fast Search algorithm Underwater gravity-aided navigation Path planning efficiency Quick Rapidly-exploring Random Trees*(QRRT*)

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Analysis and monitoring of drug therapy in a patient with peptic ulcer complicated by infection:A case report

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World Journal of Clinical Cases 2024年第8期12卷 1530-1535页

作者： Yan-Ping Gou Yue Huang Li Chen wei zheng Yun-Hua zheng The Second People’s Hospital of Meishan City&Renshou County People’s Hospital Meishan 620500Sichuan ProvinceChina Quality Evaluation and Medical Record Management The Affiliated Hospital of Southwest Jiaotong University&The Third People's Hospital of ChengduChengdu 610000Sichuan ProvinceChina Patriotic Health Campaign Qionglai City Health BureauChengdu 610000Sichuan ProvinceChina

BACKGROUND The role of primary-level medical pharmacists in medical institutions in China is limited;therefore,it is necessary to explore the role of pharmacists in the process of drug treatment.CASE SUMMARY A Chinese pharmacist participated in the complete treatment of a patient with a duodenal ulcer.The rationale for drug treatment was evaluated,and adjustments were made to the antacid and anti-infective regimen,as well as the dose and frequency of administration.Body temperature,routine blood examination,and adverse drug reactions were strictly monitored.During treatment,the pharmacist recommended anti-infective therapy with ampicillin-sulbactam,which effectively controlled the infection.Additionally,the pharmacist suggested changing famotidine to lansoprazole for acid suppression and gastroprotective treatment,combined with Chinese patent medicine such as Kangfuxin Liquid.This is the first case report of a pharmacist in primary-level medical institutions adjusting drug use for patients with duodenal ulcer and pulmonary infection.CONCLUSION A pharmacist participated in the treatment process,provided individualized medication adjustment,and achieved good clinical results.

关键词： Ampicillin-sulbactam Famotidine Lansoprazole Kangfuxin Liquid Chinese pharmacist Case report

Superplastic Tension Behavior of Dissimilar TC4/SP700 Laminate through Diffusion Bonding

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 353-363页

作者： Qianwen Zhang Tianle Li Yanbin Han wei zheng Xifeng Li Jianjun Wu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072China AVIC Xi’an Aircraft Industry Group Company Ltd Xi’an710089China Institute of Forming Technology and Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200030China

Superplastic forming is a practical method to manufacture complex-shaped parts of titanium alloys with large deformation.Laminated parts of dissimilar titanium alloys fabricated by superplastic forming can achieve excellent performance by combining the advantages of components.This work displays the superplastic tension behavior and microstructural evolution of dissimilar TC4/SP700 laminate prepared by the diffusion bonding process.Two titanium alloys can achieve metallurgical bonding at parameters of 800℃/1 h/5 MPa.Except for dynamic recrystallization and grain growth behaviors upon superplastic tension,stress-induced phase transformation plays an important role inαtoβphase transformation apart from the elevated temperature.The superplastic deformation can be attributed to the grain boundary sliding accommodated multiplex motion of dislocations.In addition,the retained strengths of all dissimilar TC4/SP700 laminates after superplastic deformation with different strain rates and temperatures range from 807 to 890 MPa.

关键词： TC4/SP700 laminate Diffusion bonding Microstructure Superplastic tension Strength

Cross-Project Software Defect Prediction Based on SMOTE and Deep Canonical Correlation Analysis

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Computers, Materials & Continua 2024年第2期78卷 1687-1711页

作者： Xin Fan Shuqing Zhang Kaisheng Wu wei zheng Yu Ge School of Software Nanchang Hangkong UniversityNanchang330063China Software Testing and Evaluation Center Nanchang Hangkong UniversityNanchang330063China

Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consider linear correlations between features(indicators)of the source and target projects.These models are not capable of evaluating non-linear correlations between features when they exist,for example,when there are differences in data distributions between the source and target projects.As a result,the performance of such CPDP models is compromised.In this paper,this paper proposes a novel CPDP method based on Synthetic Minority Oversampling Technique(SMOTE)and Deep Canonical Correlation Analysis(DCCA),referred to as S-DCCA.Canonical Correlation Analysis(CCA)is employed to address the issue of non-linear correlations between features of the source and target projects.S-DCCA extends CCA by incorporating the MlpNet model for feature extraction from the dataset.The redundant features are then eliminated by maximizing the correlated feature subset using the CCA loss function.Finally,cross-project defect prediction is achieved through the application of the SMOTE data sampling technique.Area Under Curve(AUC)and F1 scores(F1)are used as evaluation metrics.This paper conducted experiments on 27 projects from four public datasets to validate the proposed method.The results demonstrate that,on average,our method outperforms all baseline approaches by at least 1.2%in AUC and 5.5%in F1 score.This indicates that the proposed method exhibits favorable performance characteristics.

关键词： Cross-project defect prediction deep canonical correlation analysis feature similarity

Software Defect Prediction Method Based on Stable Learning

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Computers, Materials & Continua 2024年第1期78卷 65-84页

作者： Xin Fan Jingen Mao Liangjue Lian Li Yu wei zheng Yun Ge College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210012China School of Software Nanchang Hangkong UniversityNanchang330029China Software Testing and Evaluation Center Nanchang Hangkong UniversityNanchang330029China

The purpose of software defect prediction is to identify defect-prone code modules to assist software quality assurance teams with the appropriate allocation of resources and labor.In previous software defect prediction studies,transfer learning was effective in solving the problem of inconsistent project data distribution.However,target projects often lack sufficient data,which affects the performance of the transfer learning model.In addition,the presence of uncorrelated features between projects can decrease the prediction accuracy of the transfer learning model.To address these problems,this article propose a software defect prediction method based on stable learning(SDP-SL)that combines code visualization techniques and residual networks.This method first transforms code files into code images using code visualization techniques and then constructs a defect prediction model based on these code images.During the model training process,target project data are not required as prior knowledge.Following the principles of stable learning,this paper dynamically adjusted the weights of source project samples to eliminate dependencies between features,thereby capturing the“invariance mechanism”within the data.This approach explores the genuine relationship between code defect features and labels,thereby enhancing defect prediction performance.To evaluate the performance of SDP-SL,this article conducted comparative experiments on 10 open-source projects in the PROMISE dataset.The experimental results demonstrated that in terms of the F-measure,the proposed SDP-SL method outperformed other within-project defect prediction methods by 2.11%-44.03%.In cross-project defect prediction,the SDP-SL method provided an improvement of 5.89%-25.46% in prediction performance compared to other cross-project defect prediction methods.Therefore,SDP-SL can effectively enhance within-and cross-project defect predictions.

关键词： Software defect prediction code visualization stable learning sample reweight residual network

Equitable Cluster Partition of Planar Graphs with Girth at Least 12

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Journal of Mathematical Research with Applications 2024年第2期44卷 152-160页

作者： Xiaoling LIU Lei SUN wei zheng Shandong Normal University Department of Mathematics and Statistics

An equitable(Ok1, Ok2,..., Okm)-partition of a graph G, which is also called a k cluster m-partition, is the partition of V(G) into m non-empty subsets V1, V2,..., Vm such that for every integer i in {1, 2,..., m}, G[Vi] is a graph with components of order at most k, and for each distinct pair i, j in {1,..., m}, there is-1 ≤ |Vi|-|Vj| ≤ 1. In this paper, we proved that every planar graph G with minimum degree δ(G) ≥ 2 and girth g(G) ≥ 12 admits an equitable(O71, O72,..., O7m)-partition, for any integer m ≥ 2.

关键词： equitable cluster partition planar graph girth discharging

No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes

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Forest Ecosystems 2024年第3期11卷 255-265页

作者： Jiayun Zou Yahuang Luo Rupert Seidl Dominik Thom Jie Liu Lisa Geres Tobias Richter Linjiang Ye wei zheng Liangliang Ma Jie Song Kun Xu Dezhu Li Lianming Gao Sebastian Seibold Ecosystem Dynamics and Forest Management Research Group School of Life SciencesTechnical University of MunichHans-Carl-von-Carlowitz-Platz 285354FreisingGermany State Key Laboratory of Plant Diversity and Specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunming650201YunnanChina Lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang674100China Berchtesgaden National Park Doktorberg 683471Germany Gund Institute for Environment University of Vermont617 Main StreetBurlingtonVT 1105405USA Faculty of Biological Sciences Institute for EcologyEvolution and DiversityConservation BiologyGoethe University FrankfurtFrankfurt am MainGermany University of Chinese Academy of Sciences Beijing10049China TUD Dresden University of Technology Forest ZoologyPienner Str.701737TharandtGermany

An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable conditions.However,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different landscapes.To study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical Asia.We quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic diversity.To elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across landscapes.We found no general pattern of BPRs across landscapes and elevations.Relationships were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical forests.BPRs were largely congruent between taxonomic,functional and phylogenetic diversity.We found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical forests.In temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific traits.The effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across landscapes.Our study highlights the context-dependence of BPRs across elevation gradients and landscapes.Species traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of biodiversity.Furthermore,our findings highlight that potential trade-offs between conserving biodiversity and fostering ecos

关键词： Biodiversity-ecosystem functioning Climate mitigation Elevation gradients Forest management Forest productivity Functional traits Nature conservation Phylogenetic diversity

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