scholarly journals Forward Regularity Preservation Property of Register Pushdown Systems

2021 ◽  
Vol E104.D (3) ◽  
pp. 370-380
Author(s):  
Ryoma SENDA ◽  
Yoshiaki TAKATA ◽  
Hiroyuki SEKI
Keyword(s):  
Preservation Property

scholarly journals On the Relationship between Variational Level Set-Based and SOM-Based Active Contours

2015 ◽  
Vol 2015 ◽  
pp. 1-19 ◽  
Author(s):  
Mohammed M. Abdelsamea ◽  
Giorgio Gnecco ◽  
Mohamed Medhat Gaber ◽  
Eyad Elyan
Keyword(s):  
Level Set ◽  
Active Contour ◽  
Active Contours ◽  
Level Set Methods ◽  
Energy Functional ◽  
Self Organizing Maps ◽  
Complex Shapes ◽  
Variational Level Set ◽  
Preservation Property ◽  
The Relationship

Most Active Contour Models (ACMs) deal with the image segmentation problem as a functional optimization problem, as they work on dividing an image into several regions by optimizing a suitable functional. Among ACMs, variational level set methods have been used to build an active contour with the aim of modeling arbitrarily complex shapes. Moreover, they can handle also topological changes of the contours. Self-Organizing Maps (SOMs) have attracted the attention of many computer vision scientists, particularly in modeling an active contour based on the idea of utilizing the prototypes (weights) of a SOM to control the evolution of the contour. SOM-based models have been proposed in general with the aim of exploiting the specific ability of SOMs to learn the edge-map information via their topology preservation property and overcoming some drawbacks of other ACMs, such as trapping into local minima of the image energy functional to be minimized in such models. In this survey, we illustrate the main concepts of variational level set-based ACMs, SOM-based ACMs, and their relationship and review in a comprehensive fashion the development of their state-of-the-art models from a machine learning perspective, with a focus on their strengths and weaknesses.

New Dimension in Relational Database Preservation

2013 ◽  
pp. 160-173
Author(s):  
Ricardo André Pereira Freitas ◽  
José Carlos Ramalho
Keyword(s):  
Conceptual Model ◽  
Digital Media ◽  
Information Technologies ◽  
Relational Databases ◽  
Reference Model ◽  
Digital Preservation ◽  
Specific Class ◽  
Mapping Algorithm ◽  
Preservation Property ◽  
Database Semantics

Due to the expansion and growth of information technologies, much of human knowledge is now recorded on digital media. A new problem in the digital universe has arisen: Digital Preservation. This chapter addresses the problems of Digital Preservation and focuses on the conceptual model within a specific class of digital objects: Relational Databases. Previously, a neutral format was adopted to pursue the goal of platform independence and to achieve a standard format in the digital preservation of relational databases, both data and structure (logical model). The authors address the preservation of relational databases by focusing on the conceptual model of the database, considering the database semantics as an important preservation “property.” For the representation of this higher layer of abstraction present in databases, they use an ontology-based approach. At this higher abstraction level exists inherent Knowledge associated to the database semantics that the authors tentatively represent using “Web Ontology Language” (OWL). From the initial prototype, they develop a framework (supported by case studies) and establish a mapping algorithm for the conversion between databases and OWL. The ontology approach is adopted to formalize the knowledge associated to the conceptual model of the database and also a methodology to create an abstract representation of it. The system is based on the functional axes (ingestion, administration, dissemination, and preservation) of the OAIS reference model.

scholarly journals Global smoothness preservation by multivariate singular integrals

2000 ◽  
Vol 61 (3) ◽  
pp. 489-506
Author(s):  
George A. Anastassiou ◽  
Sorin G. Gal
Keyword(s):  
Singular Integrals ◽  
Moduli Of Smoothness ◽  
Jackson Type ◽  
Global Smoothness Preservation ◽  
Univariate Case ◽  
Global Smoothness ◽  
Preservation Property

By using various kinds of moduli of smoothness, it is established that the multivariate variants of the well-known singular integrals of Picard, Poisson-Cauchy, Gauss-Weierstrass and their Jackson-type generalisations satisfy the “global smoothness preservation” property. The results are extensions of those proved by the authors for the univariate case.

scholarly journals VLASOV SCALING FOR THE GLAUBER DYNAMICS IN CONTINUUM

2011 ◽  
Vol 14 (04) ◽  
pp. 537-569 ◽  
Author(s):  
DMITRI FINKELSHTEIN ◽  
YURI KONDRATIEV ◽  
OLEKSANDR KUTOVIY
Keyword(s):  
Correlation Functions ◽  
Particle Density ◽  
Type Equation ◽  
Glauber Dynamics ◽  
Positive Density ◽  
Infinite Volume ◽  
Integrable Potential ◽  
Vlasov Scaling ◽  
Preservation Property

We consider Vlasov-type scaling for the Glauber dynamics in continuum with a positive integrable potential, and construct rescaled and limiting evolutions of correlation functions. Convergence to the limiting evolution for the positive density system in infinite volume is shown. Chaos preservation property of this evolution gives a possibility to derive a nonlinear Vlasov-type equation for the particle density of the limiting system.

SEPARATION PROBLEMS AND FORCING

2013 ◽  
Vol 13 (01) ◽  
pp. 1350002
Author(s):  
JINDŘICH ZAPLETAL
Keyword(s):  
Set Theory ◽  
Descriptive Set Theory ◽  
Closed Sets ◽  
Infinite Game ◽  
Preservation Property ◽  
Sets Of Uniqueness ◽  
Descriptive Set ◽  
Fusion Type ◽  
Separation Problems

Certain separation problems in descriptive set theory correspond to a forcing preservation property, with a fusion type infinite game associated to it. As an application, it is consistent with the axioms of set theory that the circle 𝕋 can be covered by ℵ1 many closed sets of uniqueness while a much larger number of H-sets is necessary to cover it.

SOME RESULTS ABOUT MIT ORDER AND IMIT CLASS OF LIFE DISTRIBUTIONS

2006 ◽  
Vol 20 (3) ◽  
pp. 481-496 ◽  
Author(s):  
Xiaohu Li ◽  
Maochao Xu
Keyword(s):  
Renewal Process ◽  
Residual Life ◽  
Random Time ◽  
Mean Residual Life ◽  
Stochastic Comparisons ◽  
Inactivity Time ◽  
Mean Inactivity Time ◽  
Life Distributions ◽  
Preservation Property

We investigate some new properties of mean inactivity time (MIT) order and increasing MIT (IMIT) class of life distributions. The preservation property of MIT order under increasing and concave transformations, reversed preservation properties of MIT order, and IMIT class of life distributions under the taking of maximum are developed. Based on the residual life at a random time and the excess lifetime in a renewal process, stochastic comparisons of both IMIT and decreasing mean residual life distributions are conducted as well.

scholarly journals A mass conserving mixed stress formulation for the Stokes equations

2019 ◽  
Vol 40 (3) ◽  
pp. 1838-1874 ◽  
Author(s):  
Jay Gopalakrishnan ◽  
Philip L Lederer ◽  
Joachim Schöberl
Keyword(s):  
Finite Elements ◽  
Degrees Of Freedom ◽  
Stokes Equations ◽  
Computational Cost ◽  
Mass Conservation ◽  
Rates Of Convergence ◽  
Exact Mass ◽  
Conservation Property ◽  
Pressure Independent ◽  
Preservation Property

Abstract We propose stress formulation of the Stokes equations. The velocity $u$ is approximated with $H(\operatorname{div})$-conforming finite elements providing exact mass conservation. While many standard methods use $H^1$-conforming spaces for the discrete velocity $H(\operatorname{div})$-conformity fits the considered variational formulation in this work. A new stress-like variable $\sigma $ equalling the gradient of the velocity is set within a new function space $H(\operatorname{curl} \operatorname{div})$. New matrix-valued finite elements having continuous ‘normal-tangential’ components are constructed to approximate functions in $H(\operatorname{curl} \operatorname{div})$. An error analysis concludes with optimal rates of convergence for errors in $u$ (measured in a discrete $H^1$-norm), errors in $\sigma $ (measured in $L^2$) and the pressure $p$ (also measured in $L^2$). The exact mass conservation property is directly related to another structure-preservation property called pressure robustness, as shown by pressure-independent velocity error estimates. The computational cost measured in terms of interface degrees of freedom is comparable to old and new Stokes discretizations.

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