Singularities

We study a 1D transport equation with nonlocal velocity and show the formation of singularities in finite time for a generic family of initial data. By adding a diffusion term the finite time singularity is prevented and the solutions exist globally in time. 1. Introduction In this paper we study the nature of the solutions to the following class of equations (1.1)

14p noel_noel 17-01-2013 30 5   Download

An algorithm based on the Generalized Hebbian Algorithm is described that allows the singular value decomposition of a dataset to be learned based on single observation pairs presented serially. The algorithm has minimal memory requirements, and is therefore interesting in the natural language domain, where very large datasets are often used, and datasets quickly become intractable. The technique is demonstrated on the task of learning word and letter bigram pairs from text.

8p bunthai_1 06-05-2013 28 2   Download

The paper examines some of the characteristic features of natural language interaction with a database system and its implications for the processing of singular definite descriptions. Some proposals are made for assessing the uniqueness claim of the singular definite article in the context of retrieval from a relational database. Other standard assumptions such as the extensional evaluation and referent evaluation exclusively in the database - rather than within the discourse model - are critically examined.

5p buncha_1 08-05-2013 17 1   Download

In this chapter, we present a general approach to the analysis of coefficients of generating functions that is not restricted to polar singularities and extends to a large class of functions that have moderate growth or decay at their dominant singularities. This chapter presents the following content: Prelude, standard function scale, singularity analysis, schemas and transfer theorems.

56p allbymyself_08 22-02-2016 7 1   Download

Singularity analysis paves the way to the analysis of a large quantity of generating functions, as provided by the symbolic method expounded in Chapters I–III. In this chapter we illustrate this situation with numerous examples related to languages, permutations, trees, and graphs of various sorts. As in chapter 5, most analyses are organized into broad classes called schemas.

59p allbymyself_08 22-02-2016 10 1   Download

In this paper, the identifying undamaged-beam status based on singular spectrum analysis (SSA) and wavelet neural networks (WNN) is presented. First, a database is built from measured sets and SSA which works as a frequency-based filter. A WNN model is then designed which consists of the wavelet frame building, wavelet structure designing and establishing a solution for training the WNN.

15p dieutringuyen 07-06-2017 11 1   Download

Grammar: Chapter 1 - Introduction to nouns. Singular count nouns: Nouns are words we use for people, places, or things. Use A, AN, THE before a singular count noun. Use A before a singular count noun that begins with a consonant sound. Use AN before a singular count noun that begins with a vowel sound (u e o a i). Proper nouns (danh từ riêng) are names of specific people, places, or things. Proper nouns begin with a capital letter (chữ cái Hoa). All other nouns are common nouns.

6p nguyencongvan91 24-10-2010 234 82   Download

A singular noun is a word that names one person, place, thing, or idea: brother, classroom, piglet, and joy. A plural noun names more than one person, place, thing, or idea: brothers, classrooms, piglets, and joys. A collective noun names a group. When the collective noun refers to the group as a whole, it is singular. When it refers to the individual group members, the collective noun is plural. The class meets two days a week. (singular).

352p contentnew 09-05-2012 142 82   Download

Tuyển tập các báo cáo nghiên cứu khoa học ngành toán học được đăng trên tạp chí toán học quốc tế đề tài: The asymptotics of eigenvalues and trace formula of operator associated with one singular problem

24p dauphong11 04-02-2012 42 7   Download

Inspired by Lorenz’ remarkable chaotic flow, we describe in this paper the structure of all C 1 robust transitive sets with singularities for flows on closed 3-manifolds: they are partially hyperbolic with volume-expanding central direction, and are either attractors or repellers. In particular, any C 1 robust attractor with singularities for flows on closed 3-manifolds always has an invariant foliation whose leaves are forward contracted by the flow, and has positive Lyapunov exponent at every orbit, showing that any C 1 robust attractor resembles a geometric Lorenz attractor. ...

59p tuanloccuoi 04-01-2013 31 6   Download

Reduction of the singularities of codimension one singular foliations in dimension three By Felipe Cano Contents 0. Introduction 1. Blowing-up singular foliations 1.1. Adapted singular foliations 1.2. Permissible centers 1.3. Vertical invariants 1.4. First properties of presimple singularities 2. Global strategy 2.1. Reduction to presimple singularities. Statement 2.2. Good points. Bad points. Equi-reduction 2.3. Finiteness of bad points 2.4. The influency locus 2.5. The local control theorem 2.6. Destroying cycles 2.7. Global criteria of blowing-up 3. Local control 3.1.

106p tuanloccuoi 04-01-2013 20 6   Download

In this paper we describe the propagation of C ∞ and Sobolev singularities for the wave equation on C ∞ manifolds with corners M equipped with a Rie2 1 mannian metric g. That is, for X = M × Rt , P = Dt − ∆M , and u ∈ Hloc (X) solving P u = 0 with homogeneous Dirichlet or Neumann boundary conditions, we show that WFb (u) is a union of maximally extended generalized broken bicharacteristics. This result is a C ∞ counterpart of Lebeau’s results for the propagation of analytic singularities on real analytic manifolds with...

65p dontetvui 17-01-2013 31 6   Download

I had taken Mrs. Prest into my confidence; in truth without her I should have made but little advance, for the fruitful idea in the whole business dropped from her friendly lips. It was she who invented the short cut, who severed the Gordian knot. It is not supposed to be the nature of women to rise as a general thing to the largest and most liberal view—I mean of a practical scheme; but it has struck me that they sometimes throw off a bold conception—such as a man would not have risen to—with singular serenity....

123p minhhaiqt90 07-11-2010 51 5   Download

Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: THE COVARIABILITY BETWEEN ANOMALOUS NORTHEAST MONSOON RAINFALL IN MALAYSIA AND SEA SURFACE TEMPERATURE IN INDIAN-PACIFIC SECTOR: A SINGULAR VALUE DECOMPOSITION ANALYSIS APPROACH

15p hoami_266 15-09-2011 31 5   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Positive Solution of Singular Boundary Value Problem for a Nonlinear Fractional Differential Equation

12p sting05 10-02-2012 34 5   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article A Parameter Robust Method for Singularly Perturbed Delay Differential Equations Fevzi Erdogan

14p dauphong14 11-02-2012 28 5   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Positive Solution to a Singular p-Laplacian BVP with Sign-Changing Nonlinearity

21p sting10 29-02-2012 23 5   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article An Exponentially Fitted Method for Singularly Perturbed Delay Differential Equations Fevzi Erdogan

9p sting10 29-02-2012 33 5   Download

We investigate point singularities of Willmore surfaces, which for example appear as blowups of the Willmore flow near singularities, and prove that closed Willmore surfaces with one unit density point singularity are smooth in codimension one. As applications we get in codimension one that the Willmore flow of spheres with energy less than 8π exists for all time and converges to a round sphere and further that the set of Willmore tori with energy less than 8π − δ is compact up to M¨bius transformations. o 1. Introduction For an immersed closed surface f : ...

44p tuanloccuoi 04-01-2013 23 5   Download

This paper is a continuation of Fefferman’s program [7] for studying the geometry and analysis of strictly pseudoconvex domains. The key idea of the program is to consider the Bergman and Szeg¨ kernels of the domains as o analogs of the heat kernel of Riemannian manifolds. In Riemannian (or conformal) geometry, the coefficients of the asymptotic expansion of the heat kernel can be expressed in terms of the curvature of the metric; by integrating the coefficients one obtains index theorems in various settings. ...

18p noel_noel 17-01-2013 23 5   Download