• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 224
  • 39
  • 39
  • 39
  • 39
  • 39
  • 39
  • 18
  • 16
  • 9
  • 1
  • Tagged with
  • 644
  • 644
  • 299
  • 26
  • 24
  • 23
  • 21
  • 20
  • 19
  • 19
  • 18
  • 18
  • 18
  • 18
  • 17
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

K(-I) OBSTRUCTIONS TO FACTORING AN OPEN MANIFOLD

Unknown Date (has links)
Let M('n+k) be an open PL manifold of dimension n + k (GREATERTHEQ) 6, let X be a finite polyhedron, and suppose f:M('n+k )(--->)(' )X(' )x R('k) is a bounded homotopy equivalence. If k (GREATERTHEQ) 1, we use radial engulfing and Siebenmann's twist-gluing (twist = id.) to construct a manifold M(,1) with infinite cyclic cover M and a bounded homotopy equivalence f(,1):M(,1) (--->) X x S('1) x R('k-1). By iterating this construction we obtain a manifold M(,k-1) and a bounded homotopy equivalence f(,k-1):M(,k-1) (--->) X x S('1) x ... x S('1) x R. We show that the Siebenmann obstruction in (')K(,0)(Z(pi)(,1)M(,k-1)) to factoring M(,k-1) = N(,k-1) x R is an element of (')K(,-k+1)(Z(pi)(,1)X). Thus we get a sequence of obstructions (sigma)(,i) (ELEM) K(,-i+1)(Z(pi)(,1)X) , j (LESSTHEQ) i (LESSTHEQ) k, such that M = Y x R('k-j+1), for some PL manifold Y, if and only if each (sigma)(,i) is 0. / Source: Dissertation Abstracts International, Volume: 44-06, Section: B, page: 1858. / Thesis (Ph.D.)--The Florida State University, 1983.
2

MORE SOLUTIONS OF THE EINSTEIN EQUATIONS (RELATIVITY)

Unknown Date (has links)
A method of analytically solving first order nonlinear ordinary differential equations with polynomial coefficients is presented. This method essentially updates the work of G. Darboux, completed in 1878, by using the algebraic capabilities of the modern digital computer to solve systems of nonlinear algebraic equations. The solution of these systems results in integration factors for the original first order differential equation. / This method of solution is applied to the spherically symmetric but time-dependent Einstein equations. It is then shown that when the spherical symmetry constraint is removed and the same form of the metric is otherwise used, the time-dependent Einstein equations can be solved by essentially the same procedure. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3531. / Thesis (Ph.D.)--The Florida State University, 1984.
3

RELATIVISTIC GRAVITATION AND THE LARGE NUMBERS HYPOTHESIS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-10, Section: B, page: 4863. / Thesis (Ph.D.)--The Florida State University, 1979.
4

A method for distinguishing complete momentum transfer reactions from other reaction mechanisms

Unknown Date (has links)
A method for distinguishing complete momentum transfer reactions from other types of reaction mechanisms is discussed. The nuclear reactions used to perform this study were $\sp{12}$C($\sp{12}$C,HI) at E$\sb{\rm cm}$ = 31.5, 21.75, and 12 MeV and $\sp{10}$B($\sp{12}$C,HI) and $\sp{12}$C($\sp{10}$B,HI) at E$\sb{\rm cm}$ = 28.64, 19.77, and 10.91 MeV. These data were measured with high precision at three laboratory angles, typically 8$\sp\circ$, 16$\sp\circ$, and 25$\sp\circ$ and with lesser precision at several other angles using a time of flight (TOF) system. The TOF system utilized a microchannel plate detector along with a silicon surface barrier detector 270 cm downstream to obtain time information. By using this arrangement, very low energy heavy residues could be measured (down to 3-4 MeV). / In order to distinguish the complete momentum transfer reactions from the other reaction mechanisms, transformations into the center of mass frame were made. By examining the symmetry of the center of mass velocity distributions obtained (assuming a symmetric center of mass angular distribution), information on the reaction process could be made evident. Specifically, for complete momentum transfer reactions, it is expected that the heavy residues will display a symmetry about 90$\sp\circ$ in the center of mass and thus have symmetric center of mass velocity and angular distributions. For other reaction mechanisms this would not be the case unless the entrance channel used were symmetric. In the case of a symmetric entrance channel this symmetry would be manifested regardless of reaction mechanism. The $\sp{12}$C + $\sp{12}$C thus allowed us to test the degree of symmetry one would achieve under ideal circumstances for this type of data and analysis. / A statistical model analysis is also performed and then compared to the data. Most of the data is shown to be due to a complete momentum transfer process and good agreement between the statistical model predictions and the data is realized. / Source: Dissertation Abstracts International, Volume: 50-02, Section: B, page: 0608. / Major Professor: Lawrence C. Dennis. / Thesis (Ph.D.)--The Florida State University, 1988.
5

USE OF THE THIRTEEN-MOMENT APPROXIMATION TO DESCRIBE THE PROPAGATION AND INTERACTION OF ELECTROMAGNETIC WAVES IN THE IONOSPHERE

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6559. / Thesis (Ph.D.)--The Florida State University, 1968.
6

A STUDY OF THE REACTION MECHANISMS OF DIRECT REACTIONS ON LIGHT NUCLEI

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-11, Section: B, page: 6559. / Thesis (Ph.D.)--The Florida State University, 1971.
7

THE DESIGN AND ASSESSMENT OF AN INTRODUCTORY PHYSICS LABORATORY DEVELOPED USING BEHAVIORAL OBJECTIVES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 36-08, Section: B, page: 4021. / Thesis (Ph.D.)--The Florida State University, 1975.
8

CESIUM-133 AND CHLORINE-35 NMR IN ANTIFERROMAGNETIC CESIUM-COBALT TRICHLORIDE

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 36-08, Section: B, page: 4020. / Thesis (Ph.D.)--The Florida State University, 1975.
9

NUCLEAR REACTION SPECTROSCOPY WITH EVEN MASS CERIUM TARGETS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 33-03, Section: B, page: 1225. / Thesis (Ph.D.)--The Florida State University, 1972.
10

THE REDUCTION POSTULATE AND CONCEPTUAL PROBLEM IN QUANTUM MECHANICS

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 34-04, Section: B, page: 1672. / Thesis (Ph.D.)--The Florida State University, 1973.

Page generated in 0.0502 seconds