发布求助
文献互助 智能选刊 最新文献

Portugaliae Mathematica最新文献

筛选
英文 中文
On the Hadamard product of degenerate subvarieties 关于退化亚变种的Hadamard积
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2018-04-04 DOI: 10.4171/pm/2029
G. Calussi, E. Carlini, G. Fatabbi, A. Lorenzini
{"title":"On the Hadamard product of degenerate subvarieties","authors":"G. Calussi, E. Carlini, G. Fatabbi, A. Lorenzini","doi":"10.4171/pm/2029","DOIUrl":"https://doi.org/10.4171/pm/2029","url":null,"abstract":"We consider generic degenerate subvarieties $X_isubsetmathbb{P}^n$. We determine an integer $N$, depending on the varieties, and for $ngeq N$ we compute dimension and degree formulas for the Hadamard product of the varieties $X_i$. Moreover, if the varieties $X_i$ are smooth, their Hadamard product is smooth too. For $n<N$, if the $X_i$ are generically $d_i$-parameterized, the dimension and degree formulas still hold. However, the Hadamard product can be singular and we give a lower bound for the dimension of the singular locus.","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2018-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/pm/2029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45700213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 9
Special issue on computational algebra 计算代数特刊
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2018-02-08 DOI: 10.4171/PM/2000
J. Araújo, P. Cameron
{"title":"Special issue on computational algebra","authors":"J. Araújo, P. Cameron","doi":"10.4171/PM/2000","DOIUrl":"https://doi.org/10.4171/PM/2000","url":null,"abstract":"","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"171-172"},"PeriodicalIF":0.8,"publicationDate":"2018-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/2000","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49083286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
A new class of monohedral pentagonal spherical tilings with GeoGebra 一类新的带有GeoGebra的单面五边形球面平铺
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2018-02-08 DOI: 10.4171/PM/2006
A. Breda, José Manuel Dos Santos Dos Santos
{"title":"A new class of monohedral pentagonal spherical tilings with GeoGebra","authors":"A. Breda, José Manuel Dos Santos Dos Santos","doi":"10.4171/PM/2006","DOIUrl":"https://doi.org/10.4171/PM/2006","url":null,"abstract":"","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"257-266"},"PeriodicalIF":0.8,"publicationDate":"2018-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/2006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46068240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 5
On classifying objects with specified groups of automorphisms, friendly subgroups, and Sylow tower groups 关于具有指定自同构群、友好子群和Sylow塔群的对象的分类
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2018-02-08 DOI: 10.4171/PM/2004
L. H. Soicher
{"title":"On classifying objects with specified groups of automorphisms, friendly subgroups, and Sylow tower groups","authors":"L. H. Soicher","doi":"10.4171/PM/2004","DOIUrl":"https://doi.org/10.4171/PM/2004","url":null,"abstract":"We describe some group theory which is useful in the classification of combinatorial objects having given groups of automorphisms. In particular, we show the usefulness of the concept of a friendly subgroup: a subgroup H of a group K is a friendly subgroup of K if every subgroup of K isomorphic to H is conjugate in K to H. We explore easy-to-test sufficient conditions for a subgroup H to be a friendly subgroup of a finite group K, and for this, present an algorithm for determining whether a finite group H is a Sylow tower group.","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"233-242"},"PeriodicalIF":0.8,"publicationDate":"2018-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/2004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46475633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Corrigendum to ‘‘Positive integers divisible by the product of their nonzero digits’’, Portugaliae Math. 64 (2007), 1: 75–85 “可被其非零数字之积整除的正整数”的勘误表，葡萄牙数学64 (2007)，1:75-85
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-11-10 DOI: 10.4171/PM/1999
J. Koninck, F. Luca
{"title":"Corrigendum to ‘‘Positive integers divisible by the product of their nonzero digits’’, Portugaliae Math. 64 (2007), 1: 75–85","authors":"J. Koninck, F. Luca","doi":"10.4171/PM/1999","DOIUrl":"https://doi.org/10.4171/PM/1999","url":null,"abstract":"","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"169-170"},"PeriodicalIF":0.8,"publicationDate":"2017-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/1999","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45116581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 2
Approximation rates for regularized level set power mean curvature flow 正则化水平集幂平均曲率流的逼近率
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-11-10 DOI: 10.4171/PM/1995
H. Kröner
{"title":"Approximation rates for regularized level set power mean curvature flow","authors":"H. Kröner","doi":"10.4171/PM/1995","DOIUrl":"https://doi.org/10.4171/PM/1995","url":null,"abstract":"","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"115-126"},"PeriodicalIF":0.8,"publicationDate":"2017-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/1995","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49332925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 6
Corrigendum and addendum to ‘‘Hierarchic control for a coupled parabolic system’’, Portugaliae Math. 73 (2016), 2: 115–137 “耦合抛物型系统的层次控制”，数学学报，2016，(2):115-137
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-11-10 DOI: 10.4171/PM/1998
Víctor Hernández-Santamaría, L. Teresa, A. Poznyak
{"title":"Corrigendum and addendum to ‘‘Hierarchic control for a coupled parabolic system’’, Portugaliae Math. 73 (2016), 2: 115–137","authors":"Víctor Hernández-Santamaría, L. Teresa, A. Poznyak","doi":"10.4171/PM/1998","DOIUrl":"https://doi.org/10.4171/PM/1998","url":null,"abstract":"","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"161-168"},"PeriodicalIF":0.8,"publicationDate":"2017-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/1998","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45927190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 3
Bitangents of non-smooth tropical quartics 非光滑的热带四分之一种
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-10-27 DOI: 10.4171/PM/2011
H. Lee, Yoav Len
{"title":"Bitangents of non-smooth tropical quartics","authors":"H. Lee, Yoav Len","doi":"10.4171/PM/2011","DOIUrl":"https://doi.org/10.4171/PM/2011","url":null,"abstract":"We study bitangents of non-smooth tropical plane quartics. Our main result is that with appropriate multiplicities, every such curve has 7 equivalence classes of bitangent lines. Moreover, the multiplicity of bitangent lines varies continuously in families of tropical plane curves.","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2017-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/2011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46573226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 6
Towards a pseudoequational proof theory 伪等式证明理论
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-08-31 DOI: 10.4171/PM/2012
J. Almeida, Ondvrej Kl'ima
{"title":"Towards a pseudoequational proof theory","authors":"J. Almeida, Ondvrej Kl'ima","doi":"10.4171/PM/2012","DOIUrl":"https://doi.org/10.4171/PM/2012","url":null,"abstract":"A new scheme for proving pseudoidentities from a given set {Sigma} of pseudoidentities, which is clearly sound, is also shown to be complete in many instances, such as when {Sigma} defines a locally finite variety, a pseudovariety of groups, more generally, of completely simple semigroups, or of commutative monoids. Many further examples when the scheme is complete are given when {Sigma} defines a pseudovariety V which is {sigma}-reducible for the equation x=y, provided {Sigma} is enough to prove a basis of identities for the variety of {sigma}-algebras generated by V. This gives ample evidence in support of the conjecture that the proof scheme is complete in general.","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2017-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4171/PM/2012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47125792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 9
Adaptive multilevel trust-region methods for time-dependent PDE-constrained optimization 含时PDE约束优化的自适应多级信赖域方法
IF 0.8 4区 数学
Portugaliae Mathematica Pub Date : 2017-05-03 DOI: 10.4171/PM/1992
S. Ulbrich, J. Ziems
{"title":"Adaptive multilevel trust-region methods for time-dependent PDE-constrained optimization","authors":"S. Ulbrich, J. Ziems","doi":"10.4171/PM/1992","DOIUrl":"https://doi.org/10.4171/PM/1992","url":null,"abstract":"We present a class of adaptive multilevel trust-region methods for the efficient solution of optimization problems governed by time–dependent nonlinear partial differential equations with control constraints. The algorithm is based on the ideas of the adaptive multilevel inexact SQP-method from [26, 27]. It is in particular well suited for problems with time–dependent PDE constraints. Instead of the quasi-normal step in a classical SQP method which results in solving the linearized PDE sufficiently well, in this algorithm a (nonlinear) solver is applied to the current discretization of the PDE. Moreover, different discretizations and solvers for the PDE and the adjoint PDE may be applied. The resulting inexactness of the reduced gradient in the current discretization is controlled within the algorithm. Thus, highly efficient PDE solvers can be coupled with the proposed optimization framework. The algorithm starts with a coarse discretization of the underlying optimization problem and provides during the optimization process implementable criteria for an adaptive refinement strategy of the current discretization based on error estimators. We prove global convergence to a stationary point of the infinitedimensional problem. Moreover, we illustrate how the adaptive refinement strategy of the algorithm can be implemented by using a posteriori error estimators for the state and the adjoint equation. Numerical results for a semilinear parabolic PDE–constrained problem with pointwise control constraints are presented. Mathematics Subject Classification (2010). 90C55 49M05 49M25 49M37","PeriodicalId":51269,"journal":{"name":"Portugaliae Mathematica","volume":"74 1","pages":"37-67"},"PeriodicalIF":0.8,"publicationDate":"2017-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45636374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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: 4
首页 上一页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信