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ZTE GSM exPower SOLUTIONS. INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO.
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《ZTE Communications》 2007年第2期68-68,共1页
ZTE’s cost-effective GSM solutions provide world class service to over 70 million subscribers in more than 30
关键词 GSM ZTE GSM exPower solutions.INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO BTS TCO
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Natural climate solutions.The way forward 被引量:1
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作者 Caichun Yin Paulo Pereira +1 位作者 Wenwu Zhao Damia Barcelo 《Geography and Sustainability》 CSCD 2023年第2期179-182,共4页
Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran... Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran-sition,or natural climate solutions(NCS).NCS involve a set of measures(e.g.,afforestation,land restoration,biochar reuse or sustainable land use practices).Implementing NCS increases carbon sequestration and mitigates climate change at the lowest costs and greenest ways.In addition,NCS practices can improve multiple ecosystem services(ES)such as air quality,flood and erosion regulation,pest control,water purification,wild food biomass,recreation or landscape aesthetics.However,unsustainable implementation of NCS,such as over-afforestation of dense mono-forest,can lead to tradeoffs with water supply,wildfire risk,and decreased grasslands and crop-lands.Therefore,to optimise the NCS implementation,reducing the tradeoffs associated and transforming the“expand ecosystem area”to“improve ecosystem management efficiency”is vital.Although NCS can contribute significantly to mitigating climate change,systematic climate actions must be accompanied by a transformation in the global society and investment in new technologies.This will be key to addressing global challenges such as the achievement of Sustainable Development Goals(SDGs),such as SDG 13(Climate Action),SDG 15(Life on Land),SDG 2(Zero Hunger),SDG 3(Good Health and Wellbeing),SDG 6(Clean Water and Sanitation),and SDG 14(Life Bellow Water). 展开更多
关键词 Natural climate solutions Climate mitigation Ecosystem services TRADEOFFS Sustainable Development Goals
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ZTE GSM exPower SOLUTIONS.INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO
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《ZTE Communications》 2007年第4期65-65,共1页
ZTE’s cost-effective GSM solutions provide world class service to over 70 million subscribers in more than 30 countries,and have helped us build strong partnerships with 12 of the world’s top thirty telecoms operators.
关键词 ZTE GSM exPower solutions INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO GSM
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ZTE GSM exPower SOLUTIONS. INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO.
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《ZTE Communications》 2007年第3期65-65,共1页
ZTE’s cost-effective GSM solutions provide world class service to over 70 million subscribers in more than 30 countries
关键词 GSM ZTE GSM exPower solutions INCREASE YOUR BUSINESS SUCCESS BY REDUCING YOUR TCO
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Hidden Properties of Mathematical Physics Equations. Double Solutions. The Realization of Integrable Structures. Emergence of Physical Structures and Observable Formations
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作者 L. I. Petrova 《Journal of Applied Mathematics and Physics》 2020年第7期1255-1262,共8页
With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various... With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various structures and formations such as waves, vortices, turbulent pulsations and others. Such properties of the mathematical physics equations, which are hidden (they appear only in the process of solving these equations), depend on the consistency of derivatives in partial differential equations and on the consistency of equations, if the equations of mathematical physics are a set of equations. This is due to the integrability of mathematical physics equations. It is shown that the equations of mathematical physics can have double solutions, namely, the solutions on the original coordinate space and the solutions on integrable structures that are realized discretely (due to any degrees of freedom). The transition from the solutions of the first type to one of the second type describes discrete transitions and the processes of origin of various structures and observable formations. Only mathematical physics equations, on what no additional conditions such as the integrability conditions are imposed, can possess such properties. The results of the present paper were obtained with the help of skew-symmetric differential forms. 展开更多
关键词 Integrability of Mathematical Physics Equations Double solutions Integrable Structures Discrete Transitions Skew-Symmetric Differential Forms
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Quantum-Mechanical Information Content of Multiples Hartree-Fock Solutions. The Multi-Reference Hartree-Fock Configuration Interaction Method
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作者 Luiz Augusto Carvalho Malbouisson Antonio Moreira de Cerqueira Sobrinho Micael Dias de Andrade 《Journal of Modern Physics》 2014年第7期543-548,共6页
The Hartree-Fock equation is non-linear and has, in principle, multiple solutions. The ωth HF extreme and its associated virtual spin-orbitals furnish an orthogonal base Bω of the full configuration interaction spac... The Hartree-Fock equation is non-linear and has, in principle, multiple solutions. The ωth HF extreme and its associated virtual spin-orbitals furnish an orthogonal base Bω of the full configuration interaction space. Although all Bω bases generate the same CI space, the corresponding configurations of each Bω base have distinct quantum-mechanical information contents. In previous works, we have introduced a multi-reference configuration interaction method, based on the multiple extremes of the Hartree-Fock problem. This method was applied to calculate the permanent electrical dipole and quadrupole moments of some small molecules using minimal and double, triple and polarized double-zeta bases. In all cases were possible, using a reduced number of configurations, to obtain dipole and quadrupole moments in close agreement with the experimental values and energies without compromising the energy of the state function. These results show the positive effect of the use of the multi-reference Hartree-Fock bases that allowed a better extraction of quantum mechanical information from the several Bω bases. But to extend these ideas for larger systems and atomic bases, it is necessary to develop criteria to build the multireference Hartree-Fock bases. In this project, we are beginning a study of the non-uniform distribution of quantum-mechanical information content of the Bω bases, searching identify the factors that allowed obtain the good results cited 展开更多
关键词 Multiple HARTREE-FOCK solutions QUANTUM MECHANICAL INFORMATION Content MULTI-REFERENCE Hartre-Fock Configuration Interaction Method
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Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
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作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
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Existence,Uniqueness and Stability of Bounded Solutions for Minkowski-Curvature Problems with Asymptotic Boundary Conditions
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作者 Tianlan CHEN Xuying TANG 《Journal of Mathematical Research with Applications》 2026年第1期57-70,共14页
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→... In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions. 展开更多
关键词 mean curvature operator UNIQUENESS asymptotic boundary conditions bounded solution
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Colorectal cancer early screening:Dilemmas and solutions 被引量:2
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作者 Di Wu Qi-Ying Song +4 位作者 Bai-Shu Dai Jie Li Xin-Xin Wang Jia-Yu Liu Tian-Yu Xie 《World Journal of Gastroenterology》 2025年第9期154-160,共7页
Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhan... Colorectal cancer(CRC)is a prevalent malignancy worldwide,posing a significant public health concern.Mounting evidence has confirmed that timely early screening facilitates the detection of incipient CRC,thereby enhancing patient prognosis.Obviously,non-participation of asymptomatic individuals in screening programs hampers early diagnosis and may adversely affect long-term outcomes for CRC patients.In this letter,we provide a comprehensive overview of the current status of early screening practices,while also thoroughly examine the dilemmas and potential solutions associated with early screening for CRC.In response to these issues,we proffer a set of recommendations directed at governmental authorities and the general public,which focus on augmenting financial investment,establishing standardized screening protocols,advancing technological capabilities,and bolstering public awareness campaigns.The importance of collaborative efforts from various stakeholders cannot be overstated in the quest to enhance early detection rates and alleviate the societal burden of CRC. 展开更多
关键词 Colorectal cancer Early screening Asymptomatic candidates DILEMMAS solutions
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Investigation of the formation processes of CO_(2) hydrate films on the interface of liquid carbon dioxide with humic acids solutions 被引量:1
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作者 Aleksey K.Sagidullin Sergey S.Skiba +1 位作者 Tatyana P.Adamova Andrey Y.Manakov 《Chinese Journal of Chemical Engineering》 2025年第3期53-61,共9页
Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the inte... Morphology and growth rate of carbon dioxide hydrate on the interface between liquid carbon dioxide and humic acid solutions were studied in this work.It was found that after the growth of the hydrate film at the interface,further growth of hydrate due to the suction of water in the capillary system formed between the wall of the cuvette and the end boundary of the hydrate layer occurs.Most probably,substantial effects on the formation of this capillary system may be caused by variations in reactor wall properties,for example,hydrophobic-hydrophilic balance,roughness,etc.We found,that the rate of CO_(2) hydrate film growth on the surface of the humic acid aqueous solution is 4-fold to lower in comparison with the growth rate on the surface of pure water.We suppose that this is caused by the adsorption of humic acid associates on the surface of hydrate particles and,as a consequence,by the deceleration of the diffusion of dissolved carbon dioxide to the growing hydrate particle. 展开更多
关键词 HYDRATES Carbon dioxide Humic acids solutions Reaction kinetics Liquid liquid reaction Film growth
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Progress in study of spray pyrolysis technology for chloride salt solutions in rare earth extraction and separation processes 被引量:1
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作者 Ziyi Cheng Xiaowei Huang +5 位作者 Zongyu Feng Jianping Long Hai Yu Meng Wang Juanyu Yang Haiqing Hao 《Journal of Rare Earths》 2025年第10期2053-2064,I0001,共13页
This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.... This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.It proposes the idea of introducing spray pyrolysis technology into the rare earth extraction and separation processes.This paper briefly describes the development history of chloride spray pyrolysis technology,focusing on the research status and application progress of rare earth chloride solution and magnesium chloride solution spray pyrolysis technology,as well as spray pyrolysis equipment.The paper also analyzes the challenges and technical intricacies associated with applying spray pyrolysis technology to chloride solutions in the rare earth extraction and separation processes.Additionally,it explores future trends and proposes strategies to facilitate the full recycling of acids and bases,streamline the process flow,and enhance the prospects for green and low-carbon rare earth metallurgy. 展开更多
关键词 Rare earths Separation processes Spray pyrolysis technology Chloride salt solutions Green recycling
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Peaked traveling wave solutions of the modified highly nonlinear Novikov equation 被引量:1
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作者 LI Hui-jun WEN Zhen-shu LI Shao-yong 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期375-394,共20页
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
关键词 modified highly nonlinear Novikov equation bifurcation dynamics peakons periodic cusp wave solutions
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Fluid therapy in acute pancreatitis comparing balanced solutions and normal saline:A systematic review,meta-analysis and trial sequential analysis 被引量:1
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作者 Lin Gao Hsiang-Wei Wang +4 位作者 Zi-Rui Liu Yi-Zhen Xu Lu Ke Wei-Qin Li John A Windsor 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期371-380,共10页
Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the t... Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the type of fluid are conflicting and generally come from small single-center randomized controlled trials(RCTs).We therefore conducted a systematic review and meta-analysis to compare the effect of balanced solutions(BS)versus NS on patient-centered clinical outcomes in AP.Methods:From four databases searched up to October 2024,we included only RCTs of adult patients with AP that compared the use of BS(including LR,acetate Ringer’s,etc.)with NS.The primary out-come was the disease advances from AP to moderately severe and severe AP(MSAP/SAP).Trial sequential analyses(TSA)were conducted to control for type-I and type-II errors and Grading of Recommendations Assessment,Development,and Evaluation(GRADE)was used to assess the quality of evidence.Results:Six RCTs were identified and included,involving 260 patients treated with BS and 298 patients with NS.Patients who received the BS had less MSAP/SAP[odds ratio(OR)=0.50,95%confidence in-terval(CI):0.29 to 0.85,P=0.01,I^(2)=0%;5 studies,299 patients],reduced the need of ICU admission(OR=0.60,95%CI:0.39 to 0.93,P=0.02,I^(2)=0%;5 studies,507 patients)and shorter length of hospital stay[mean difference(MD)=-0.88,95%CI:-1.48 to-0.28,P=0.004,I^(2)=0%;6 studies,558 patients;confirmed by TSA with high certainty]compared with those who received NS.The evidence for most of the clinical outcomes was rated as moderate to low due to the risk of bias,imprecision and inconsistency.Conclusions:BS,compared with NS,was associated with improved clinical outcomes in patients with AP.However,given the moderate to low quality of evidence for most of the outcomes assessed,further trials are warranted. 展开更多
关键词 Acute pancreatitis Fluid therapy Normal saline Balanced solution Systematic review
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Normalized Solutions of Nonlinear Choquard Equations with Nonconstant Potential
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作者 LI Nan XU Liping 《应用数学》 北大核心 2025年第1期14-29,共16页
In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with ... In this paper,we mainly focus on a type of nonlinear Choquard equations with nonconstant potential.Under appropriate hypotheses on potential function and nonlinear terms,we prove that the above Choquard equation with prescribed 2-norm has some normalized solutions by introducing variational methods. 展开更多
关键词 Nonlinear Choquard equation Potential function Variational method Normalized solution
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Methods for Exact Solutions of Nonlinear Ordinary Differential Equations
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作者 Robert CONTE Micheline MUSETTE +1 位作者 Tuen Wai NG WU Chengfa 《数学进展》 北大核心 2025年第2期379-389,共11页
In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic... In order to find closed form solutions of nonintegrable nonlinear ordinary differential equations,numerous tricks have been proposed.The goal of this short review is to explain how a theorem of Eremenko on meromorphic solutions of some nonlinear ODEs together with some classical,19th-century results,can be turned into algorithms(thus avoiding ad hoc assumptions)which provide all(as opposed to some)solutions in a precise class.To illustrate these methods,we present some new such exact solutions,physically relevant. 展开更多
关键词 elliptic solution complex Ginzburg-Landau equation Closed-form solution Nevanlinna theory
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Stochastic Periodic Solutions for Two Populations Game Models with Impulses
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作者 HOU Meiting QIU Xiaoling 《应用数学》 北大核心 2025年第2期453-467,共15页
The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding sto... The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding stochastic and impulse. For the stochastic model without impulses, the existence and uniqueness of solution, and the existence of positive periodic solutions are proved, and a sufficient condition for strategy extinction is given. For the stochastic model with impulses, the existence of positive periodic solutions is proved. Numerical results show that noise and impulses directly affect the model, but the periodicity of the model does not change. 展开更多
关键词 Periodic solution Stochastic game IMPULSES Strategy extinct
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Least Energy Solutions for the Fractional Schrodinger–Poisson System with General Potential and Nonlinearity
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作者 ZHU Shaojuan HUANG Xianjiu 《数学进展》 北大核心 2025年第5期1031-1058,共28页
In this paper,we study the existence of least energy solutions for the following nonlinear fractional Schrodinger–Poisson system{(−∆)^(s)u+V(x)u+φu=f(u)in R^(3),(−∆)^(t)φ=u^(2)in R^(3),where s∈(3/4,1),t∈(0,1).Und... In this paper,we study the existence of least energy solutions for the following nonlinear fractional Schrodinger–Poisson system{(−∆)^(s)u+V(x)u+φu=f(u)in R^(3),(−∆)^(t)φ=u^(2)in R^(3),where s∈(3/4,1),t∈(0,1).Under some assumptions on V(x)and f,using Nehari–Pohozaev identity and the arguments of Brezis–Nirenberg,the monotonic trick and global compactness lemma,we prove the existence of a nontrivial least energy solution. 展开更多
关键词 fractional Schrodinger-Poisson system variational method Nehari-Pohozaev identity least energy solution
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Periodic Solutions for a Stochastic Stage-structure Predator-prey Model with Impulses
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作者 HOU Meiting QIU Xiaoling 《数学进展》 北大核心 2025年第6期1307-1318,共12页
A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positi... A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positive solution.Second,by selecting an appropriate Lyapunov function,we provide the sufficient condition for the existence of a positive T-periodic solution.Finally,numerical simulations illustrate our theoretical results,which show that the impulse or the white noises can result in the extinction of the predator in a certain condition. 展开更多
关键词 periodic solution stochastic noise IMPULSE
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Periodic Traveling Wave Solutions of a Single Population Model with Advection and Distributed Delay
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作者 GUO Zilin YU Tao TANG Xiaosong 《应用数学》 北大核心 2025年第4期988-995,共8页
In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave so... In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave solutions for this model under the influence of advection term and distributed delay.The obtained results indicate that weak kernel and strong kernel can both deduce the existence of periodic traveling wave solutions.Finally,we apply the main results in this paper to Logistic model and Nicholson’s blowflies model. 展开更多
关键词 Single population model Advection Distributed delay Periodic traveling wave solution
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Normalized Positive Ground State Solutions for Nonhomogeneous Kirchhoff Equations
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作者 ZHANG Xiaocang XU Liping 《应用数学》 北大核心 2025年第3期711-720,共10页
This article studies a class of nonlinear Kirchhoff equations with exponential critical growth,trapping potential,and perturbation.Under appropriate assumptions about f and h,the article obtained the existence of norm... This article studies a class of nonlinear Kirchhoff equations with exponential critical growth,trapping potential,and perturbation.Under appropriate assumptions about f and h,the article obtained the existence of normalized positive solutions for this equation via the Trudinger-Moser inequality and variational methods.Moreover,these solutions are also ground state solutions.Additionally,the article also characterized the asymptotic behavior of solutions.The results of this article expand the research of relevant literature. 展开更多
关键词 Normalized positive ground state solution Nonhomogeneous Kirchhoff equation Variational method Exponential critical growth Trapping potential
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