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Influence of toxic substances on dynamical behavior of a delayed diffusive predator-prey model

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International Journal of Biomathematics 2024年第2期17卷 177-200页

作者： Honglan Zhu Xuebing Zhang Hao Zhang Business School Huaiyin Institute of Technology Huai'an 223003P.R.China College of Mathematics and Statistics Nanjing University of Information Science and technology Nanjing210044 P.R.China jiangsu key laboratory of trafic and transportation security huaiyin institute of technology Huaian 223003P.R.China

In this paper,we propose and investigate a delayed diffusive predator-prey model affected by toxic *** first study the boundedness and persistence property of the *** analyzing the associated characteristic equation,we obtain the conditions for the existence of steady state bifurcation,Hopf bifurcation and Turing ***,we also study the Hopf bifurcation induced by the ***,our theoretical results are verified by numerical *** numerical observation results are in good agreement with the theoretically predicted *** and numerical simulations indicate that toxic substances have a great impact on the dynamics of the system.

关键词： Toxicant delay diffusion bifurcation spatial pattern

Time-domain dynamic constitutive model suitable for mucky soil site seismic response

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 1-13页

作者： Dong Qing Chen Su Jin Liguo Zhou Zhenghua Li Xiaojun Architectural Engineering institute Huaiyin Institute of TechnologyHuai’an 223600China key laboratory of Urban security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100020China institute of Geophysics China Earthquake AdministrationBeijing 100089China College of transportation Science and Engineering Nanjing Tech UniversityNanjing 211816China

Soil nonlinear behavior displays noticeable effects on the site seismic *** study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton *** integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics *** on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of *** the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear *** results verify the rationality of the new soil dynamic constitutive *** can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty *** hysteresis loop area is more extensive,and the residual strain is evident.

关键词： seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil

A high order numerical manifold method and its application to linear elastic continuous and fracture problems

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Science China(Technological Sciences) 2018年第3期61卷 346-358页

作者： YANG YongTao SUN GuanHua CAI KeJian ZHENG Hong State key laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences School of Civil and transportation Engineering NingBo University of Technology key laboratory of Urban security and Disaster Engineering Ministry ofEducation Beijing University of Technology

The numerical manifold method(NMM) is a partition of unity(PU) based method. For the purpose of obtaining better accuracy with the same mesh, high order global approximation can be adopted by increasing the order of local approximations(LAs). This,however, will cause the "linear dependence"(LD) issue, where the global matrix is rank deficient even after sufficient constraints are enforced. In this paper, through quadrilateral mesh to form the mathematical cover, a high order numerical manifold method called Quad4-COLS(NMM) is developed, where the constrained and orthonormalized least-squares method(CO-LS) is used to construct the LAs. The developed Quad4-COLS(NMM) does not need extra nodes or DOFs to construct high order global approximations, while is free from the LD issue. Nine numerical tests including five tests for linear elastic continuous problems and four tests for linear elastic fracture problems are carried out to validate the accuracy and robustness of the proposed Quad4-COLS(NMM).

关键词： partition of unity based methods numerical manifold method Quad4-COLS(NMM) crack propagation linear dependence

Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN key laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong laboratory (Guangzhou) State key laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

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Lateral deformation of embankment with the CFG pile-net structure for Yun-Gui passenger dedicated line

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Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 154-164页

作者： Pan, Gao-Feng Liu, Xian-Feng Yuan, Sheng-Yang Sun, Dan-Xi Tian, Mao-Cheng Wang, Yi-Bo Feng, Yan Jiang, Guan-Lu School of Civil Engineering Southwest Jiaotong University Chengdu 610031 China key laboratory of High-speed Railway Engineering of Ministry of Education Southwest Jiaotong University Chengdu 610031 China State key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 630031 China key laboratory for Traffic and transportation security of jiangsu Province Huaiyin Institute of Technology Huai'an 223003 China

Taking cement flyash gravel(CFG) pile-net structure embankment in the expansive soil area of the Yun-Gui (i.e., Yunnan-Guangxi) passenger dedicated line as the engineering background, a full-scale on-site embankment filling test was carried out to compare and analyze the lateral deformation law of the natural foundation and CFG pile-net composite foundation under the subgrade load. The results show that (1) the maximum lateral deformation of the natural foundation occurs at 1-2 m depth below the surface, while the maximum lateral deformation for the composite foundation appears at the depth of 0.6 times of the pile length, and the constraint effect of increasing the pile length on the lateral deformation is only obvious within the depth of 6 m. (2) The maximum lateral deformation has a linear relationship with the foundation settlement in stages. After the embankment exceeds a certain critical height, the lateral deformation develops sharply. (3) The critical filling height of the composite foundation decreases with the increase of pile length but the maximum lateral displacement decreases after stabilization. Finally, based on the hypothesis of lateral deformation stratification analysis and equal volume deformation, the method of predicting the lateral deformation of the foundation is proposed based on the measured soil parameters, and the accuracy is verified by the measured data. The research results can provide the theoretical reference for the construction design and deformation analysis of CFG pile-net structure roadbed. © 2020, Science Press. All right reserved.

关键词： Embankments

A Novel Post-Quantum Blind Signature for Log System in Blockchain

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Computer Systems Science & Engineering 2022年第6期41卷 945-958页

作者： Gang Xu Yibo Cao Shiyuan Xu Ke Xiao Xin Liu Xiubo Chen Mianxiong Dong School of Information Science and technology North China University of TechnologyBeijing100144China Beijing key laboratory of security and Privacy in Intelligent transportation Beijing Jiaotong UniversityBeijing100044China School of Information Engineering Inner Mongolia University of Science&TechnologyBaotou014010China Information security Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Muroran institute of technology Muroran050-8585Japan

In recent decades, log system management has been widely studied fordata security management. System abnormalities or illegal operations can befound in time by analyzing the log and provide evidence for intrusions. In orderto ensure the integrity of the log in the current system, many researchers havedesigned it based on blockchain. However, the emerging blockchain is facing significant security challenges with the increment of quantum computers. An attackerequipped with a quantum computer can extract the user's private key from thepublic key to generate a forged signature, destroy the structure of the blockchain,and threaten the security of the log system. Thus, blind signature on the lattice inpost-quantum blockchain brings new security features for log systems. In ourpaper, to address these, firstly, we propose a novel log system based on post-quantum blockchain that can resist quantum computing attacks. Secondly, we utilize apost-quantum blind signature on the lattice to ensure both security and blindnessof log system, which makes the privacy of log information to a large ***, we enhance the security level of lattice-based blind signature under therandom oracle model, and the signature size grows slowly compared with *** also implement our protocol and conduct an extensive analysis to prove theideas. The results show that our scheme signature size edges up subtly comparedwith others with the improvement of security level.

关键词： Log system post-quantum blockchain lattice blind signature privacy protection

Efficient simulation of spatially correlated non-stationary ground motions by wavelet-packet algorithm and spectral representation method

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 799-814页

作者： Ji Kun Cao Xuyang Wang Suyang Wen Ruizhi College of Civil and transportation Engineering Hohai UniversityNanjing 210098China The key laboratory of Urban security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100022China key laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China key laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China

Although the classical spectral representation method(SRM)has been widely used in the generation of spatially varying ground motions,there are still challenges in efficient simulation of the non-stationary stochastic vector process in *** first problem is the inherent limitation and inflexibility of the deterministic time/frequency modulation *** difficulty is the estimation of evolutionary power spectral density(EPSD)with quite a few *** tackle these problems,the wavelet packet transform(WPT)algorithm is utilized to build a time-varying spectrum of seed recording which describes the energy distribution in the time-frequency *** time-varying spectrum is proven to preserve the time and frequency marginal property as theoretical EPSD will do for the stationary *** the simulation of spatially varying ground motions,the auto-EPSD for all locations is directly estimated using the time-varying spectrum of seed recording rather than matching predefined EPSD *** the constructed spectral matrix is incorporated in SRM to simulate spatially varying non-stationary ground motions using efficient Cholesky decomposition *** addition to a good match with the target coherency model,two numerical examples indicate that the generated time histories retain the physical properties of the prescribed seed recording,including waveform,temporal/spectral non-stationarity,normalized energy buildup,and significant duration.

关键词： non-stationarity time-varying spectrum wavelet packet transform(WPT) spectral representation method(SRM) response spectrum spatially varying recordings

Assessing performance of collision mitigation brake system in Chinese traffic environment

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Journal of Central South University 2019年第10期26卷 2854-2869页

作者： ZHAO Zhi-guo ZHENG Xun-jia WANG Jian-qiang XU Qing KODAKA Kenji jiangsu key laboratory of Traffic and transportation security Huaiyin Institute of TechnologyHuaian 223001China State key laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Honda R&D Co.Ltd.Automobile R&D Center Tochigi 321-3393Japan

Advanced driver-assistance systems such as Honda’s collision mitigation brake system(CMBS)can help achieve traffic *** this paper,the naturalistic driving study and a series of simulations are combined to better evaluate the performance of the CMBS in the Chinese traffic ***,because safety-critical situations can be diverse especially in the Chinese environment,the Chinese traffic-accident characteristics are analyzed according to accident statistics over the past 17 ***,10 Chinese traffic-accident scenarios accounting for more than 80%of traffic accidents are *** each typical scenario,353 representative cases are collected from the traffic-management department of *** real-world accident cases are then reconstructed by the traffic-accident-reconstruction software PC-Crash on the basis of accident-scene *** study also proposes a systematic analytical process for estimating the effectiveness of the technology using the co-simulation platform of PC-Crash and rateEFFECT,in which 176 simulations are analyzed in detail to assess the accident-avoidance performance of the *** overall collision-avoidance effectiveness reaches 82.4%,showing that the proposed approach is efficient for avoiding collisions,thereby enhancing traffic safety and improving traffic management.

关键词： active-safety technology effectiveness assessment accident reconstruction autonomous emergency braking PC-Crash

Design parameter optimization method for a prestressed steel structure driven by multi-factor coupling

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1066-1083页

作者： Guo-Liang SHI Zhan-Sheng LIU De-Chun LU Qing-Wen ZHANG Majid DEZHKAM Ze-Qiang WANG Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China The key laboratory of Urban security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Beijing Building Construction Research institute Co. Ltd.Beijing 100039China

To achieve efficient structural design,it is crucial to reduce the cost of materials while ensuring structural *** study proposes an optimization method for design parameters(DPs)in a prestressed steel structure driven by multi-factor *** accomplish this,a numerical proxy model of prestressed steel structures is established with integration of DPs and mechanical parameters(MPs).A data association-parameter analysis-optimization selection system is established.A correlation between DPs and MPs is established using a back propagation(BP)neural *** correlation provides samples for parameter analysis and optimization *** are used to characterize the safety of the *** on the safety grade analysis,the key DPs that affect the mechanical properties of the structure are obtained.A mapping function is created to match the MPs and the key *** optimal structural DPs are obtained by setting structural materials as the optimization objective and safety energy as the constraint *** theoretical model is applied to an 80-m-span gymnasium and verified with a scale test physical *** MPs obtained using the proposed method are in good agreement with the experimental *** with the traditional design method,the design cycle can be shortened by more than 90%.Driven by the optimal selection method,a saving of more than 20% can be achieved through reduction of structural material ***,the cross-sectional dimensions of radial cables have a substantial influence on vertical *** initial tension and cross-sectional size of the upper radial cable exhibit the most pronounced impact on the stress distribution in that *** initial tension and cross-sectional size of the lower radial cable hold the greatest sway over the stress distribution in that cable.

关键词： structure design association relationship performance analysis optimum selection experimental verification