Proceedings. Mathematical, physical, and engineering sciences最新文献_第6页

A geostatistical extreme-value framework for fast simulation of natural hazard events. 自然灾害事件快速模拟的地质统计学极值框架。

IF 3.5

Proceedings. Mathematical, physical, and engineering sciences Pub Date : 2016-05-01 DOI: 10.1098/rspa.2015.0855

Benjamin D Youngman, David B Stephenson

引用次数: 19

Expansion shock waves in regularized shallow-water theory. 正则化浅水理论中的膨胀激波。

IF 3.5

Proceedings. Mathematical, physical, and engineering sciences Pub Date : 2016-05-01 DOI: 10.1098/rspa.2016.0141

Gennady A El, Mark A Hoefer, Michael Shearer

引用次数: 19

Generic stabilizability for time-delayed feedback control. 时滞反馈控制的一般稳定性。

IF 3.5

Proceedings. Mathematical, physical, and engineering sciences Pub Date : 2016-05-01 DOI: 10.1098/rspa.2015.0593

J Sieber

{"title":"Generic stabilizability for time-delayed feedback control.","authors":"J Sieber","doi":"10.1098/rspa.2015.0593","DOIUrl":"https://doi.org/10.1098/rspa.2015.0593","url":null,"abstract":"Time-delayed feedback control is one of the most successful methods to discover dynamically unstable features of a dynamical system in an experiment. This approach feeds back only terms that depend on the difference between the current output and the output from a fixed time T ago. Thus, any periodic orbit of period T in the feedback-controlled system is also a periodic orbit of the uncontrolled system, independent of any modelling assumptions. It has been an open problem whether this approach can be successful in general, that is, under genericity conditions similar to those in linear control theory (controllability), or if there are fundamental restrictions to time-delayed feedback control. We show that, in principle, there are no restrictions. This paper proves the following: for every periodic orbit satisfying a genericity condition slightly stronger than classical linear controllability, one can find control gains that stabilize this orbit with extended time-delayed feedback control. While the paper's techniques are based on linear stability analysis, they exploit the specific properties of linearizations near autonomous periodic orbits in nonlinear systems, and are, thus, mostly relevant for the analysis of nonlinear experiments.","PeriodicalId":520758,"journal":{"name":"Proceedings. Mathematical, physical, and engineering sciences","volume":" ","pages":"20150593"},"PeriodicalIF":3.5,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1098/rspa.2015.0593","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34561718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Crack nucleation using combined crystal plasticity modelling, high-resolution digital image correlation and high-resolution electron backscatter diffraction in a superalloy containing non-metallic inclusions under fatigue. 结合晶体塑性建模、高分辨率数字图像相关和高分辨率电子背散射衍射研究含非金属夹杂的高温合金疲劳裂纹成核。

IF 3.5

Proceedings. Mathematical, physical, and engineering sciences Pub Date : 2016-05-01 DOI: 10.1098/rspa.2015.0792

Tiantian Zhang, Jun Jiang, Ben Britton, Barbara Shollock, Fionn Dunne

{"title":"Crack nucleation using combined crystal plasticity modelling, high-resolution digital image correlation and high-resolution electron backscatter diffraction in a superalloy containing non-metallic inclusions under fatigue.","authors":"Tiantian Zhang, Jun Jiang, Ben Britton, Barbara Shollock, Fionn Dunne","doi":"10.1098/rspa.2015.0792","DOIUrl":"https://doi.org/10.1098/rspa.2015.0792","url":null,"abstract":"A crystal plasticity finite-element model, which explicitly and directly represents the complex microstructures of a non-metallic agglomerate inclusion within polycrystal nickel alloy, has been developed to study the mechanistic basis of fatigue crack nucleation. The methodology is to use the crystal plasticity model in conjunction with direct measurement at the microscale using high (angular) resolution-electron backscatter diffraction (HR-EBSD) and high (spatial) resolution-digital image correlation (HR-DIC) strain measurement techniques. Experimentally, this sample has been subjected to heat treatment leading to the establishment of residual (elastic) strains local to the agglomerate and subsequently loaded under conditions of low cyclic fatigue. The full thermal and mechanical loading history was reproduced within the model. HR-EBSD and HR-DIC elastic and total strain measurements demonstrate qualitative and quantitative agreement with crystal plasticity results. Crack nucleation by interfacial decohesion at the nickel matrix/agglomerate inclusion boundaries is observed experimentally, and systematic modelling studies enable the mechanistic basis of the nucleation to be established. A number of fatigue crack nucleation indicators are also assessed against the experimental results. Decohesion was found to be driven by interface tensile normal stress alone, and the interfacial strength was determined to be in the range of 1270-1480 MPa.","PeriodicalId":520758,"journal":{"name":"Proceedings. Mathematical, physical, and engineering sciences","volume":" ","pages":"20150792"},"PeriodicalIF":3.5,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1098/rspa.2015.0792","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34562162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 62

Half conformally flat gradient Ricci almost solitons. 半共形平坦梯度里奇几乎孤子。

IF 3.5

Proceedings. Mathematical, physical, and engineering sciences Pub Date : 2016-05-01 DOI: 10.1098/rspa.2016.0043

M Brozos-Vázquez, E García-Río, X Valle-Regueiro

引用次数: 10