As Malaysia seeks to enhance its educational development,understanding student attitudes toward various scientific disciplines—particularly STEM fields—becomes crucial.This study investigates the perceptions of pre-...As Malaysia seeks to enhance its educational development,understanding student attitudes toward various scientific disciplines—particularly STEM fields—becomes crucial.This study investigates the perceptions of pre-university students in Malaysia regarding the geoscience discipline.Data were collected through a questionnaire designed to explore students’experiences with geoscience-related subjects and their perceptions of this essential field,focusing on their understanding and interest in geoscience.展开更多
In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit ...In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit disk in R^(2):By delicate and relatively complicated computation of radial solutions to the above equation and the asymptotic expansion of solutions near the boundary of B_(1),the uniqueness of positive solutions is obtained.The results of this paper extend the uniqueness result for the semilinear equation with critical exponential growth in CHEN et al.(2022)to the case that includes a Henon term.展开更多
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy...In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting.展开更多
This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic diff...This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation.展开更多
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb...Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.展开更多
Natural product(NPT)derived from traditional Chinese medicine has a rich history as an integral part of Chinese healthcare for thousands of years.Recently,the application of NPT in sonodynamic antibacterial therapy(SD...Natural product(NPT)derived from traditional Chinese medicine has a rich history as an integral part of Chinese healthcare for thousands of years.Recently,the application of NPT in sonodynamic antibacterial therapy(SDAT)has emerged as a promising area of research.This perspective summarizes the recent NPT-based sonosensitizers in SDAT.Currently,common NPT-based sonosensitizers include curcumin,chlorophyll derivatives,hypericin,and berberine.Compared with other sonosensitizers,natural sources of NPT-based sonosensitizers with reactive oxide species production performance under ultrasound conditions,low biotoxicity,and other additional biological activity make them have application prospects in bacterial removal.Finally,the potential benefits and challenges of NPT-based nanosonosensitizers were also discussed.展开更多
Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from...Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from the cathode side.These challenges lead to poor cycle stability and severe self-discharge.From the fabrication and cost point of view,it is technologically more viable to deploy electrolyte engineering than electrode protection strategies.More importantly,a synchronous method for modulation of both cathode and anode is pivotal,which has been often neglected in prior studies.In this work,cationic poly(allylamine hydrochloride)(Pah^(+))is adopted as a low-cost dual-function electrolyte additive for ZIBs.We elaborate the synchronous effect by Pah^(+)in stabilizing Zn anode and immobilizing polyiodide anions.The fabricated Zn-iodine coin cell with Pah^(+)(ZnI_(2) loading:25 mg cm^(−2))stably cycles 1000 times at 1 C,and a single-layered 3.4 cm^(2) pouch cell(N/P ratio~1.5)with the same mass loading cycles over 300 times with insignificant capacity decay.展开更多
Shikonin,a naphthoquinone compound derived from the root of Lithospermum erythrorhizon,has been extensively studied for its antibacterial,antioxidant,and anti-inflammatory properties.Increasing evidence highlights its...Shikonin,a naphthoquinone compound derived from the root of Lithospermum erythrorhizon,has been extensively studied for its antibacterial,antioxidant,and anti-inflammatory properties.Increasing evidence highlights its potential in treating inflammation-related diseases.However,its clinical application is hindered by challenges such as poor water solubility,rapid metabolism in vivo,and other limitations.Recent advancements have demonstrated that encapsulating shikonin within nanocarriers can significantly enhance its water solubility and pharmacokinetic profile.Building on this,this perspective paper outlines the current landscape of inflammation treatment,explores the anti-inflammatory mechanisms of shikonin,reviews the latest progress in shikonin-based nanomaterials for anti-inflammatory applications,and discusses the challenges and future directions for the clinical translation of shikonin nanoformulations.展开更多
Grain crushing is commonly encountered in deep foundation engineering,high rockfill dam engineering,railway engineering,mining engineering,coastal engineering,petroleum engineering,and other geoscience application.Gra...Grain crushing is commonly encountered in deep foundation engineering,high rockfill dam engineering,railway engineering,mining engineering,coastal engineering,petroleum engineering,and other geoscience application.Grain crushing is affected by fundamental soil characteristics,such as their mineral strength,grain size and distribution,grain shape,density and specimen size,and also by external factors including stress magnitude and path,loading rate and duration,degree of saturation,temperature and geochemical environment.Crushable material becomes a series of different materials with the change in its grading during grain crushing,resulting in a decrease in strength and dilatancy and an increase in compressibility.Effects of grain crushing on strength,dilatancy,deformation and failure mechanisms have been extensively investigated through laboratory testing,discrete element method(DEM)modelling,Weibull statistics,and constitutive modelling within the framework of the extended crushing-dependent critical state theory or the energy-based theory.Eleven papers summarized in this review article for this special issue addressed the above issues in grain crushing through the advanced testing and modelling.展开更多
Background: Three-dimensional printing (3DP) technologies are a trendsetting topic, also in the field of surgery. Preoperative planning for maxillofacial and neurological surgery, for instance, increasingly involves s...Background: Three-dimensional printing (3DP) technologies are a trendsetting topic, also in the field of surgery. Preoperative planning for maxillofacial and neurological surgery, for instance, increasingly involves skull models obtained by 3DP. However, the cranial replicas currently used in this context have been shown to not reproduce the exact anatomy of the individual patient undergoing surgery. Objective: The present study aimed at investigating the extent to which manual editing, using current computer software tools, can improve skull models derived from medical images. Methods: Skull computed tomography (CT) was obtained on three cadavers and?sent to three institutions that provide preoperative 3DP services. Each institute independently?performed 3D reconstructions, including routine manual editing, and subsequently produced the replicas. The models were then qualitatively compared with the respective original skull. For?quantitative comparison surface scans of particular regions of interest were made and the deviations assessed using 3-matic software (Materialise, Leuven, Belgium). Results: Routine manual editing of CT images resulted in replicas that were clear improvements over automatically generated reconstructions. This was particularly the case for teeth artefacts and thin-walled entities (e.g. paranasal sinuses). Conversely, however, many anatomical structures remained incorrectly rendered (e.g. orbitae, pterygoid processes, and sella turcica). Extraosseous calcifications had regularly not been removed. After extensive manual editing, however, replicas were able to provide largely submillimeter accuracy (mean deviation 0.2496 mm;standard deviation ±0.2276 mm). Conclusions: This study confirms that manual editing with current computer science tools does improve the quality of CT-based 3D printed skull models. But, it also demonstrates that a number of structures remain largely incorrectly rendered when edited in the presently used surgical framework. Conversely, it shows that highly accurate replicas are feasible, provided that extensive manual editing is performed.展开更多
This study aims to determine the phenomenological bifurcation(P-bifurcation)occur-ring in the van der Pol(VDP)neuronal model of burst neurons with a random signal.We observe the P-bifurcation under an intense noise st...This study aims to determine the phenomenological bifurcation(P-bifurcation)occur-ring in the van der Pol(VDP)neuronal model of burst neurons with a random signal.We observe the P-bifurcation under an intense noise stimulus which would become chaotic transitions.Bursting and spiking simulations are used to describe the causes of chaotic transitions between two periodic phases that are the reason for the neuronal activities.Ran-domness plays a crucial role in detecting the P-bifurcation.To determine the equilibrium points,stability or instability of the stochastic VDP equation,and bifurcation,we use the stochastic averaging method and some related theorems.Apart from theoretical methods,we also examine numerical simulations in the particular case of that stochastic equation that illustrates the outcome of theorems for various noise types.The most striking part of our theoretical findings is that these results are also valid for the Izhikevich-FitzHugh model,Bonhoeffer-van der Pol oscillator in dynamical systems of neuroscience.Finally,we will discuss some applications of the VDP equation in neuronal activity.展开更多
Bio-inspired optimization algorithms[1,2]are a set of optimization algorithms inspired by natural phenomena,such as evolutionary processes,social behaviours,and swarm intelligence[3].These algorithms attempt to simula...Bio-inspired optimization algorithms[1,2]are a set of optimization algorithms inspired by natural phenomena,such as evolutionary processes,social behaviours,and swarm intelligence[3].These algorithms attempt to simulate these processes to solve optimization problems[4,5].Classical bio-inspired algorithms include genetic algorithm,ant colony optimization,artificial bee colony,particle swarm optimization,firefly algorithm,Japanese tree frog algorithm,Harris hawks optimization[6],slime mould algorithm[7],grey wolf optimization,sparrow search algorithm,whale optimization algorithm,etc.Fig.1 shows the taxonomy of common bio-inspired optimization algorithms.There are some recent newly proposed bio-inspired algorithms,such as Siberian tiger optimization[8],jellyfish search algorithm[9],etc.展开更多
Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, ...Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, software testing and analysis are two of the critical methods, which significantly benefit from the advancements in deep learning technologies. Due to the successful use of deep learning in software security, recently,researchers have explored the potential of using large language models(LLMs) in this area. In this paper, we systematically review the results focusing on LLMs in software security. We analyze the topics of fuzzing, unit test, program repair, bug reproduction, data-driven bug detection, and bug triage. We deconstruct these techniques into several stages and analyze how LLMs can be used in the stages. We also discuss the future directions of using LLMs in software security, including the future directions for the existing use of LLMs and extensions from conventional deep learning research.展开更多
This paper deals with the monotonicity of limit wave speed c0(h)to a perturbed g KdV equation.We show the decrease of c0(h)by combining the analytic method and the numerical technique.Our results solve a special case ...This paper deals with the monotonicity of limit wave speed c0(h)to a perturbed g KdV equation.We show the decrease of c0(h)by combining the analytic method and the numerical technique.Our results solve a special case of the open question presented by Yan et al.,and the method potentially provides a way to study the monotonicity of c0(h)for general m∈N^(+).展开更多
Two sharp Chernoff type inequalities are derived for star bodies in R2,one is an extension of the dual Chernoff-Ou-Pan inequality,and the other is the reverse Chernoff type inequality.Furthermore,we establish a genera...Two sharp Chernoff type inequalities are derived for star bodies in R2,one is an extension of the dual Chernoff-Ou-Pan inequality,and the other is the reverse Chernoff type inequality.Furthermore,we establish a generalized dual symmetric mixed Chernoff inequality for two planar star bodies.As a direct consequence,a new proof of the dual symmetric mixed isoperimetric inequality is presented.展开更多
The hot deformation behavior of the premium GH4738 alloy was investigated in the temperature range of 1313 to 1353 K at strain rates of 0.01 to 1 s^(−1)using the hot compression test.To accurately predict flow stress,...The hot deformation behavior of the premium GH4738 alloy was investigated in the temperature range of 1313 to 1353 K at strain rates of 0.01 to 1 s^(−1)using the hot compression test.To accurately predict flow stress,three novel strain compensation constitutive equations were developed and rigorously assessed.The results indicate that the power function model(correlation coefficients r=0.98544)demonstrates greater prediction accuracy compared to other functions,with a calculated average activation energy of 507.968 kJ mol−1.Additionally,electron backscattered diffraction technology and transmission electron microscopy were used to analyze the evolution of the alloy microstructure during dynamic recrystallization under different deformation conditions.The results show that under high-temperature and large deformation conditions,the dislocation density and the degree of grain rotation increase,which promotes the formation and growth of new recrystallized grains,so that recrystallization is completed when the deformation amount reaches 30%.Besides,the increase in the temperature not only enhances the thermal activation mechanism,but also improves the grain size uniformity and texture consistency.Meanwhile,the carbide inhibits grain overgrowth by pinning grain boundaries,maintaining a fine and uniform grain structure of the alloy,and thereby improving the plasticity of the material.展开更多
In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system w...In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system with three singular straight lines,and derive all possible phase portraits under corresponding parameter conditions.Then we show the existence and dynamics of two types of peaked traveling wave solutions including peakons and periodic cusp wave solutions.The exact explicit expressions of two peakons are given.Besides,we also derive smooth solitary wave solutions,periodic wave solutions,compacton solutions,and kink-like(antikink-like)solutions.Numerical simulations are further performed to verify the correctness of the results.Most importantly,peakons and periodic cusp wave solutions are newly found for the equation,which extends the previous results.展开更多
ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential sec...ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future directions.Through this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users.展开更多
An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of c...An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of curvature entropy.As its application,a novel proof of the log-Minkowski inequality of curvature entropy in the plane is given.展开更多
文摘As Malaysia seeks to enhance its educational development,understanding student attitudes toward various scientific disciplines—particularly STEM fields—becomes crucial.This study investigates the perceptions of pre-university students in Malaysia regarding the geoscience discipline.Data were collected through a questionnaire designed to explore students’experiences with geoscience-related subjects and their perceptions of this essential field,focusing on their understanding and interest in geoscience.
基金Supported by the Natural Science Foundation of China(12571122,12061010)。
文摘In this paper,we study the uniqueness of positive solutions to the following semilinear equations{-Δu=λ|x|^(α)ue^(u^(2)),in B_(1),u=0,onδB_(1)ueu2;in B_(1);u=0;on@B_(1);whereλ>0,α>-2;B_(1)denotes the unit disk in R^(2):By delicate and relatively complicated computation of radial solutions to the above equation and the asymptotic expansion of solutions near the boundary of B_(1),the uniqueness of positive solutions is obtained.The results of this paper extend the uniqueness result for the semilinear equation with critical exponential growth in CHEN et al.(2022)to the case that includes a Henon term.
基金Supported by the National Natural Science Foundation of China(12261018)Universities Key Laboratory of Mathematical Modeling and Data Mining in Guizhou Province(2023013)。
文摘In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting.
基金Supported by the National Natural Science Foundation of China(12001074)the Research Innovation Program of Graduate Students in Hunan Province(CX20220258)+1 种基金the Research Innovation Program of Graduate Students of Central South University(1053320214147)the Key Scientific Research Project of Higher Education Institutions in Henan Province(25B110025)。
文摘This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation.
基金Supported by the Science and Technology Program of Guizhou Province(Grant No.QKHJC QN[2025]362)the National Natural Science Foundation of China(Grant No.12361005).
文摘Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.
基金supported by the Innovation and Entrepreneurship Training Program for College Students(X2025102911746,X2025102910483).
文摘Natural product(NPT)derived from traditional Chinese medicine has a rich history as an integral part of Chinese healthcare for thousands of years.Recently,the application of NPT in sonodynamic antibacterial therapy(SDAT)has emerged as a promising area of research.This perspective summarizes the recent NPT-based sonosensitizers in SDAT.Currently,common NPT-based sonosensitizers include curcumin,chlorophyll derivatives,hypericin,and berberine.Compared with other sonosensitizers,natural sources of NPT-based sonosensitizers with reactive oxide species production performance under ultrasound conditions,low biotoxicity,and other additional biological activity make them have application prospects in bacterial removal.Finally,the potential benefits and challenges of NPT-based nanosonosensitizers were also discussed.
基金supported by the financial support from the National Research Foundation,Singapore,under its Singapore-China Joint Flagship Project(Clean Energy).
文摘Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from the cathode side.These challenges lead to poor cycle stability and severe self-discharge.From the fabrication and cost point of view,it is technologically more viable to deploy electrolyte engineering than electrode protection strategies.More importantly,a synchronous method for modulation of both cathode and anode is pivotal,which has been often neglected in prior studies.In this work,cationic poly(allylamine hydrochloride)(Pah^(+))is adopted as a low-cost dual-function electrolyte additive for ZIBs.We elaborate the synchronous effect by Pah^(+)in stabilizing Zn anode and immobilizing polyiodide anions.The fabricated Zn-iodine coin cell with Pah^(+)(ZnI_(2) loading:25 mg cm^(−2))stably cycles 1000 times at 1 C,and a single-layered 3.4 cm^(2) pouch cell(N/P ratio~1.5)with the same mass loading cycles over 300 times with insignificant capacity decay.
基金supported by the National Natural Science Foundation of China(82373393),Xinjiang Uygur Autonomous Region“Tianchi Yingcai”Project(2023TCYCQNBS02)Xinjiang Uygur Autonomous Region Colleges and Universities Basic Research Operating Expenses Scientific Research Project(XJEDU2022P106).
文摘Shikonin,a naphthoquinone compound derived from the root of Lithospermum erythrorhizon,has been extensively studied for its antibacterial,antioxidant,and anti-inflammatory properties.Increasing evidence highlights its potential in treating inflammation-related diseases.However,its clinical application is hindered by challenges such as poor water solubility,rapid metabolism in vivo,and other limitations.Recent advancements have demonstrated that encapsulating shikonin within nanocarriers can significantly enhance its water solubility and pharmacokinetic profile.Building on this,this perspective paper outlines the current landscape of inflammation treatment,explores the anti-inflammatory mechanisms of shikonin,reviews the latest progress in shikonin-based nanomaterials for anti-inflammatory applications,and discusses the challenges and future directions for the clinical translation of shikonin nanoformulations.
基金financial support from the National Science Foundation of China (Grant Nos. 51922024, 41831282, 51678094 and 51578096)
文摘Grain crushing is commonly encountered in deep foundation engineering,high rockfill dam engineering,railway engineering,mining engineering,coastal engineering,petroleum engineering,and other geoscience application.Grain crushing is affected by fundamental soil characteristics,such as their mineral strength,grain size and distribution,grain shape,density and specimen size,and also by external factors including stress magnitude and path,loading rate and duration,degree of saturation,temperature and geochemical environment.Crushable material becomes a series of different materials with the change in its grading during grain crushing,resulting in a decrease in strength and dilatancy and an increase in compressibility.Effects of grain crushing on strength,dilatancy,deformation and failure mechanisms have been extensively investigated through laboratory testing,discrete element method(DEM)modelling,Weibull statistics,and constitutive modelling within the framework of the extended crushing-dependent critical state theory or the energy-based theory.Eleven papers summarized in this review article for this special issue addressed the above issues in grain crushing through the advanced testing and modelling.
文摘Background: Three-dimensional printing (3DP) technologies are a trendsetting topic, also in the field of surgery. Preoperative planning for maxillofacial and neurological surgery, for instance, increasingly involves skull models obtained by 3DP. However, the cranial replicas currently used in this context have been shown to not reproduce the exact anatomy of the individual patient undergoing surgery. Objective: The present study aimed at investigating the extent to which manual editing, using current computer software tools, can improve skull models derived from medical images. Methods: Skull computed tomography (CT) was obtained on three cadavers and?sent to three institutions that provide preoperative 3DP services. Each institute independently?performed 3D reconstructions, including routine manual editing, and subsequently produced the replicas. The models were then qualitatively compared with the respective original skull. For?quantitative comparison surface scans of particular regions of interest were made and the deviations assessed using 3-matic software (Materialise, Leuven, Belgium). Results: Routine manual editing of CT images resulted in replicas that were clear improvements over automatically generated reconstructions. This was particularly the case for teeth artefacts and thin-walled entities (e.g. paranasal sinuses). Conversely, however, many anatomical structures remained incorrectly rendered (e.g. orbitae, pterygoid processes, and sella turcica). Extraosseous calcifications had regularly not been removed. After extensive manual editing, however, replicas were able to provide largely submillimeter accuracy (mean deviation 0.2496 mm;standard deviation ±0.2276 mm). Conclusions: This study confirms that manual editing with current computer science tools does improve the quality of CT-based 3D printed skull models. But, it also demonstrates that a number of structures remain largely incorrectly rendered when edited in the presently used surgical framework. Conversely, it shows that highly accurate replicas are feasible, provided that extensive manual editing is performed.
文摘This study aims to determine the phenomenological bifurcation(P-bifurcation)occur-ring in the van der Pol(VDP)neuronal model of burst neurons with a random signal.We observe the P-bifurcation under an intense noise stimulus which would become chaotic transitions.Bursting and spiking simulations are used to describe the causes of chaotic transitions between two periodic phases that are the reason for the neuronal activities.Ran-domness plays a crucial role in detecting the P-bifurcation.To determine the equilibrium points,stability or instability of the stochastic VDP equation,and bifurcation,we use the stochastic averaging method and some related theorems.Apart from theoretical methods,we also examine numerical simulations in the particular case of that stochastic equation that illustrates the outcome of theorems for various noise types.The most striking part of our theoretical findings is that these results are also valid for the Izhikevich-FitzHugh model,Bonhoeffer-van der Pol oscillator in dynamical systems of neuroscience.Finally,we will discuss some applications of the VDP equation in neuronal activity.
文摘Bio-inspired optimization algorithms[1,2]are a set of optimization algorithms inspired by natural phenomena,such as evolutionary processes,social behaviours,and swarm intelligence[3].These algorithms attempt to simulate these processes to solve optimization problems[4,5].Classical bio-inspired algorithms include genetic algorithm,ant colony optimization,artificial bee colony,particle swarm optimization,firefly algorithm,Japanese tree frog algorithm,Harris hawks optimization[6],slime mould algorithm[7],grey wolf optimization,sparrow search algorithm,whale optimization algorithm,etc.Fig.1 shows the taxonomy of common bio-inspired optimization algorithms.There are some recent newly proposed bio-inspired algorithms,such as Siberian tiger optimization[8],jellyfish search algorithm[9],etc.
文摘Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, software testing and analysis are two of the critical methods, which significantly benefit from the advancements in deep learning technologies. Due to the successful use of deep learning in software security, recently,researchers have explored the potential of using large language models(LLMs) in this area. In this paper, we systematically review the results focusing on LLMs in software security. We analyze the topics of fuzzing, unit test, program repair, bug reproduction, data-driven bug detection, and bug triage. We deconstruct these techniques into several stages and analyze how LLMs can be used in the stages. We also discuss the future directions of using LLMs in software security, including the future directions for the existing use of LLMs and extensions from conventional deep learning research.
基金Supported by the National Natural Science Foundation of China(12071162)the Natural Science Foundation of Fujian Province(2021J01302)the Fundamental Research Funds for the Central Universities(ZQN-802)。
文摘This paper deals with the monotonicity of limit wave speed c0(h)to a perturbed g KdV equation.We show the decrease of c0(h)by combining the analytic method and the numerical technique.Our results solve a special case of the open question presented by Yan et al.,and the method potentially provides a way to study the monotonicity of c0(h)for general m∈N^(+).
基金supported by the Postgraduate Scientic Research Innovation Project of Chongqing Normal University(YKC24010)Chunna Zeng's research was supported by the Major Special Project of the National Natural Science Foundation of China(12141101)+2 种基金the Young Top-Talent program of Chongqing(CQYC2021059145)the Technology Research Foundation of Chongqing Educational committee(KJZD-K202200509)the Natural Science Foundation Project of Chongqing(CSTB2024NSCQ-MSX0937)。
文摘Two sharp Chernoff type inequalities are derived for star bodies in R2,one is an extension of the dual Chernoff-Ou-Pan inequality,and the other is the reverse Chernoff type inequality.Furthermore,we establish a generalized dual symmetric mixed Chernoff inequality for two planar star bodies.As a direct consequence,a new proof of the dual symmetric mixed isoperimetric inequality is presented.
基金supported by the National Key R&D Program of China(No.2021YFB3700403).
文摘The hot deformation behavior of the premium GH4738 alloy was investigated in the temperature range of 1313 to 1353 K at strain rates of 0.01 to 1 s^(−1)using the hot compression test.To accurately predict flow stress,three novel strain compensation constitutive equations were developed and rigorously assessed.The results indicate that the power function model(correlation coefficients r=0.98544)demonstrates greater prediction accuracy compared to other functions,with a calculated average activation energy of 507.968 kJ mol−1.Additionally,electron backscattered diffraction technology and transmission electron microscopy were used to analyze the evolution of the alloy microstructure during dynamic recrystallization under different deformation conditions.The results show that under high-temperature and large deformation conditions,the dislocation density and the degree of grain rotation increase,which promotes the formation and growth of new recrystallized grains,so that recrystallization is completed when the deformation amount reaches 30%.Besides,the increase in the temperature not only enhances the thermal activation mechanism,but also improves the grain size uniformity and texture consistency.Meanwhile,the carbide inhibits grain overgrowth by pinning grain boundaries,maintaining a fine and uniform grain structure of the alloy,and thereby improving the plasticity of the material.
基金Supported by the National Natural Science Foundation of China(12071162)the Natural Science Foundation of Fujian Province(2021J01302)the Fundamental Research Funds for the Central Universities(ZQN-802).
文摘In this paper,we focus on peaked traveling wave solutions of the modified highly nonlinear Novikov equation by dynamical systems approach.We obtain a traveling wave system which is a singular planar dynamical system with three singular straight lines,and derive all possible phase portraits under corresponding parameter conditions.Then we show the existence and dynamics of two types of peaked traveling wave solutions including peakons and periodic cusp wave solutions.The exact explicit expressions of two peakons are given.Besides,we also derive smooth solitary wave solutions,periodic wave solutions,compacton solutions,and kink-like(antikink-like)solutions.Numerical simulations are further performed to verify the correctness of the results.Most importantly,peakons and periodic cusp wave solutions are newly found for the equation,which extends the previous results.
文摘ChatGPT is a powerful artificial intelligence(AI)language model that has demonstrated significant improvements in various natural language processing(NLP) tasks. However, like any technology, it presents potential security risks that need to be carefully evaluated and addressed. In this survey, we provide an overview of the current state of research on security of using ChatGPT, with aspects of bias, disinformation, ethics, misuse,attacks and privacy. We review and discuss the literature on these topics and highlight open research questions and future directions.Through this survey, we aim to contribute to the academic discourse on AI security, enriching the understanding of potential risks and mitigations. We anticipate that this survey will be valuable for various stakeholders involved in AI development and usage, including AI researchers, developers, policy makers, and end-users.
基金supported by the NSFC(12171378)supported by the Characteristic innovation projects of universities in Guangdong province(2023K-TSCX381)+3 种基金supported by the Young Top-Talent program of Chongqing(CQYC2021059145)the Major Special Project of NSFC(12141101)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-K202200509)the Natural Science Foundation Project of Chongqing(CSTB2024NSCQ-MSX0937).
文摘An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of curvature entropy.As its application,a novel proof of the log-Minkowski inequality of curvature entropy in the plane is given.
