Journal of Mathematical Analysis and Applications最新文献_第9页

System tautochrone motion path for centrifugal pendulum vibration absorbers 离心摆式吸振器的系统同时运动轨迹

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-27 DOI: 10.1016/j.jmaa.2025.129994

Ryan Monroe, Bruce Geist

{"title":"System tautochrone motion path for centrifugal pendulum vibration absorbers","authors":"Ryan Monroe, Bruce Geist","doi":"10.1016/j.jmaa.2025.129994","DOIUrl":"10.1016/j.jmaa.2025.129994","url":null,"abstract":"<div><div>Centrifugal Pendulum Vibration Absorbers (CPVAs) have been in use for over a century and have become integral in addressing torsional vibrations in rotating machinery across a wide range of applications in both the aerospace and automotive industries. Proper tuning of the pendulum, such that it counteracts the engine-order fluctuating torques acting on the rotor during operation, enables the device to effectively attenuate vibrations across the full range of engine operating speeds. However, as operating amplitudes increase, the dynamic stability and performance of these passive torsional smoothing devices are highly dependent upon the motion path defined for their pendulous masses. In fact, the pendulum natural frequency commonly shifts as a function of their swing amplitude. Tautochronic motion paths can eliminate this resonant frequency shift as excitation levels increase and can thus overcome the common detuning issues associated with existing paths within the epicycloid family. At present, approximate tautochrone motion paths for CPVAs are derived using simplifying assumptions, which uncouples the pendulum and rotor dynamics. In this paper, using variational calculus, a system tautochrone motion path that accounts for the pendulum to rotor inertial coupling is derived. Its use results in tautochronic motion of the entire oscillatory system including both pendulum and rotor. Numerical simulations of the system forced response show that a system tautochrone motion path has distinct vibration control advantages, including enhanced stability and vibration correction performance. Most fundamentally, a new concept of order-tuning in these systems is for the first time identified, where a pendulum following a system tautochrone motion path retains a fixed order tuning for all feasible system energy levels. That is, the paper presents a more exact order tuning concept, expressed in terms of the square root of system energy, thereby accounting for pendulum motion in addition to rotor speed effects on tuning order.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"555 1","pages":"Article 129994"},"PeriodicalIF":1.2,"publicationDate":"2025-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145049179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Positive solutions for prescribed mean curvature equations with critical growth in the whole R2 在整个R2中具有临界增长的规定平均曲率方程的正解

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-27 DOI: 10.1016/j.jmaa.2025.130009

Wendel L. da Silva, Elisandra Gloss, Uberlandio B. Severo

引用次数: 0

Determination of the one-dimensional Schrödinger operator from interior spectral data 从内部光谱数据确定一维Schrödinger算子

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-27 DOI: 10.1016/j.jmaa.2025.130013

Tiezheng Li

引用次数: 0

On the Robin problems of degenerate elliptic equations 退化椭圆型方程的Robin问题

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-27 DOI: 10.1016/j.jmaa.2025.130011

Xiaohong Guan , Zongming Guo , Fangshu Wan

引用次数: 0

Affine dual curve pair under the equi-transform of affine framed curve 仿射框架曲线等变换下的仿射对偶曲线对

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-27 DOI: 10.1016/j.jmaa.2025.130014

Shuyue Zhang , Pengcheng Li , Donghe Pei

引用次数: 0

Periodic solution of a general state-dependent predator-prey model with harvesting 具有收获的一般状态相关捕食者-猎物模型的周期解

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-26 DOI: 10.1016/j.jmaa.2025.130006

Wenxiu Li

引用次数: 0

Analysis of an abstract thermoelastic system and applications to nonplanar Bresse models 抽象热弹性系统的分析及其在非平面Bresse模型中的应用

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-26 DOI: 10.1016/j.jmaa.2025.130007

Pedro Roberto de Lima

{"title":"Analysis of an abstract thermoelastic system and applications to nonplanar Bresse models","authors":"Pedro Roberto de Lima","doi":"10.1016/j.jmaa.2025.130007","DOIUrl":"10.1016/j.jmaa.2025.130007","url":null,"abstract":"<div><div>In this paper, we study a linear system with <span><math><mi>N</mi><mo>≥</mo><mn>1</mn></math></span> hyperbolic equations coupled with <span><math><mi>M</mi><mo>≤</mo><mi>N</mi></math></span> parabolic equations. Using the classical theory of semigroups of linear operators, we prove well-posedness and provide conditions under which strong stability implies polynomial or exponential stability. From a practical point of view, this means that, in the applications of the Borichev-Tomilov and Gearhart-Prüss theorems, the resolvent estimates do not need to be verified for systems which satisfy the conditions; instead, it is enough to check a certain matrix condition associated with the coefficients of the system. Our general formulation includes, as special cases, many known results on Bresse and Timoshenko systems. In particular, our condition for exponential stability generalizes the well-known equal wave speed condition and provides a systematic way to derive this type of condition from the coefficients of the system. As applications of our general approach, we prove new results on well-posedness and asymptotic behavior of nonplanar thermoelastic Bresse systems, that have not been previously studied, and related beam models.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"554 2","pages":"Article 130007"},"PeriodicalIF":1.2,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144921479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Kernel estimates for parabolic systems of partial differential equations with unbounded coefficients 系数无界的抛物型偏微分方程组的核估计

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-26 DOI: 10.1016/j.jmaa.2025.130008

Davide Addona , Luca Lorenzi , Marianna Porfido

引用次数: 0

Multi-bubble blow-up analysis for an almost critical problem 一个近乎临界问题的多泡爆破分析

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-25 DOI: 10.1016/j.jmaa.2025.130003

Mohamed Ben Ayed, Khalil El Mehdi

{"title":"Multi-bubble blow-up analysis for an almost critical problem","authors":"Mohamed Ben Ayed, Khalil El Mehdi","doi":"10.1016/j.jmaa.2025.130003","DOIUrl":"10.1016/j.jmaa.2025.130003","url":null,"abstract":"<div><div>Consider a smooth, bounded domain <span><math><mi>Ω</mi><mo>⊂</mo><msup><mrow><mi>R</mi></mrow><mrow><mi>n</mi></mrow></msup></math></span> with <span><math><mi>n</mi><mo>≥</mo><mn>4</mn></math></span> and a smooth positive function <em>V</em>. We analyze the asymptotic behavior of a sequence of positive solutions <span><math><msub><mrow><mi>u</mi></mrow><mrow><mi>ε</mi></mrow></msub></math></span> to the equation <span><math><mo>−</mo><mi>Δ</mi><mi>u</mi><mo>+</mo><mi>V</mi><mo>(</mo><mi>x</mi><mo>)</mo><mi>u</mi><mo>=</mo><msup><mrow><mi>u</mi></mrow><mrow><mfrac><mrow><mi>n</mi><mo>+</mo><mn>2</mn></mrow><mrow><mi>n</mi><mo>−</mo><mn>2</mn></mrow></mfrac><mo>−</mo><mi>ε</mi></mrow></msup></math></span> in Ω with zero Dirichlet boundary conditions, as <span><math><mi>ε</mi><mo>→</mo><mn>0</mn></math></span>. We determine the precise blow-up rate and characterize the locations of interior concentration points in the general case of multiple blow-up, providing an exhaustive description of interior blow-up phenomena of this equation. Our result is established through a delicate analysis of the gradient of the corresponding Euler-Lagrange functional.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"554 2","pages":"Article 130003"},"PeriodicalIF":1.2,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generalized m-quasi-Einstein metrics with certain conditions on the potential vector field 势向量场上具有一定条件的广义m-拟爱因斯坦度量

IF 1.2 3区数学

Journal of Mathematical Analysis and Applications Pub Date : 2025-08-25 DOI: 10.1016/j.jmaa.2025.130004

Amalendu Ghosh

{"title":"Generalized m-quasi-Einstein metrics with certain conditions on the potential vector field","authors":"Amalendu Ghosh","doi":"10.1016/j.jmaa.2025.130004","DOIUrl":"10.1016/j.jmaa.2025.130004","url":null,"abstract":"<div><div>In this paper, we have studied generalized <em>m</em>-quasi-Einstein and <em>m</em>-quasi-Einstein manifold (<span><math><msup><mrow><mi>M</mi></mrow><mrow><mi>n</mi></mrow></msup><mo>,</mo><mi>g</mi><mo>,</mo><mi>X</mi><mo>,</mo><mi>λ</mi><mo>)</mo></math></span> satisfying certain conditions on the potential vector field. First, we classify a compact <em>m</em>-quasi-Einstein metric with geodesic potential and non-positive Ricci tensor. Then, we establish that the potential vector field <em>X</em> of an <em>m</em>-quasi-Einstein metric is Killing if <em>X</em> is an infinitesimal harmonic transformation and geodesic. Further, we classify complete non-compact <em>m</em>-quasi-Einstein metric with Ricci tensor <span><math><mi>S</mi><mo>(</mo><mi>X</mi><mo>,</mo><mi>X</mi><mo>)</mo><mo>≤</mo><mn>0</mn></math></span> when the potential vector field <em>X</em> is an infinitesimal harmonic transformation, or its energy is finite. Furthermore, we establish that the potential vector field <em>X</em> of a compact generalized <em>m</em>-quasi-Einstein manifold is Killing when it satisfies <span><math><mi>d</mi><mi>i</mi><mi>v</mi><mi>X</mi><mo>=</mo><mn>0</mn></math></span>. Finally, we prove that a generalized <em>m</em>-quasi-Einstein manifold is a warped product when its potential vector field is a non-homothetic conformal Killing.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"555 1","pages":"Article 130004"},"PeriodicalIF":1.2,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144933802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0