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  • 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.
31

Sammenhenger mellom elevers motivasjon for matematikk og den undervisningen de erfarer / Connections between Students'’ motivation for Mathematics and the Teaching they experience

Kvikne, Hild Mari January 2011 (has links)
Studien har til hensikt å undersøke elevers motivasjon for matematikk. Mer spesifikt hvilke sammenhenger det kan være mellom elevenes målorientering i matematikk og den undervisningspraksisen de erfarer i faget. Studiens overordende problemstilling er: Hvilke sammenhenger kan det være mellom elevers motivasjon for matematikk og den undervisningspraksisen de erfarer i faget? Målet med studien er å få innsikt i ulike faktorer som kan legge til rette for elevers motivasjon for matematikk. Elevenes målorientering deles inn i to hovedretninger, prestasjonsmål og læringsmål. Videre vurderes det hvorvidt målene er tilnærmingsprestasjonsmål, unngåelsesprestasjonsmål, læringsmål om instrumentell forståelse eller læringsmål om relasjonell forståelse.For å få svar på problemstillingen oppsøkes to matematikklasser ved ulike videregående skoler. Ved den ene skolen arbeider klassen med matematikk på en tradisjonell måte. Klassen ved den andre skolen arbeider med undersøkende matematikk. I begge klassene blir undervisningen observert og analysert i forhold til sju analysekategorier; læring, prestasjon, autonomi, oppgave, entusiasme, affekt og riskstøttende. Et utvalg på to elever fra hver klasse intervjues. Intervjuene analyseres ved hjelp av motivasjonsvariabler med hensikt å finne ut hvilke mål elevene har i matematikk.Resultatene fra studien indikerer at det er forskjeller på elevenes mål når de erfarer ulike former for matematikkundervisning. I klassen med tradisjonell undervisning vektlegger læreren instrumentell forståelse og oppgavene har til hensikt å øve inn spesifikke løsningsmetoder. Elevene i klassen har mål om å oppnå en god karakter i matematikk. I klassen med undersøkende matematikk fokuserer læreren på relasjonell forståelse og oppgavene får elevene til selv å finne mønster og systemer. Elevene i klassen har mål om relasjonell forståelse. Studien indikerer at det er forskjeller på undervisningspraksisene innenfor kategoriene læring, prestasjon, autonomi, oppgave og riskstøttende.
32

Some Boolean representations of the propositional calculus.

Snider, Leonard A. January 1964 (has links)
No description available.
33

A comparison of confidence interval procedures in censored life testing problems.

Coleman, William Eugene 06 1900 (has links)
Obtaining a confidence interval for a parameter[ A] of an exponential distribution is a frequent occurrence in life testing problems. Often- times the test plan used is one in which all the observations are censored at the same time point to. Several approximate confidence interval pro- cedures are available in the statistical literature; however, to the knowledge of the author, the performance characteristics of the various approximations used in these procedures have not been established analytically. The purpose of this paper is to report the results of an empirical stucy of the performance of four of these procedures with respect to the expected length of the interval, the variance of the interval length, and the coverage probability.
34

A geometric approach to Burgers' Riccati equation

Gallagher, Gerald Lee 06 1900 (has links)
The directrix approach, which gives powerful insight to the geometric structure of solutions of the general Riccati equation, is developed. Burgers' Riccati equation is derived, and conclusions are drawn utilizing the directrix approach concerning the boundedness properties of solutions of this equation with certain restrictions on parameter values. Closed form solutions are developed for Burgers' Riccati equation for certain parameter values. A method is produced to obtain the verti' cal assymptote for unbounded solutions of Burgers' Riccati equation with certain restrictions on parameter values. Conclusions drawn from the application of the directrix method to Burgers' equation are verified. A research bibliography for Riccati' s Equation is included.
35

On locating the simple cycles in a digraph

Cochrane, John Mackay 06 1900 (has links)
An algorithm is stated for finding the simple cycles in a digraph which is believed to be superior to previous algorithms. The algorithm is stated in a way which lends itself to use on a digital computer. Suitable modifications are presented which allow the algorithm to be applied to coalesced graphs. Finally, the algorithm is compared to a previously used technique, and is shown to require fewer operations.
36

Outer measure, Borel sets and Lebesgue measure in the plane.

Heming, David Millar 06 1900 (has links)
In this paper, the essential properties of general Lebesgue outer measure are discussed. The complete measure space, consisting of the general Lebesgue outer measure restricted to the measurable sets, is developed and this measure is shown to be unique. Two characterizations of measurable sets are discussed. The Borel sets are inves- tigated in the plane and more generally, in n-space, and it is shown that the a-algebra of Borel sets is equal to the product a-algebra of Borel sets on the line. Finally, the interrelationships between Lebesgue measure in the plane and the product measure of Lebesgue measures on the line are investigated. It is shown that the a-algebra of Lebesgue measurable sets properly contains the product a-algebra and that these two measures agree on the product a-algebra. It is also proven that the a-algebra of Lebesgue measurable sets is the completion of the product a-algebra. Examples are provided to illustrate that the product measure spaces discussed are not complete as well as an example of a subset of the plane which is not Lebesgue measurable.
37

A study of the two-flow model of light in the sea

Crisp, Marvin Howard 06 1900 (has links)
The principles of invariance form the foundation of the study of irradiance fields in the sea. By review of the existing theory, it is shown how these principles may be applied to imbedded layers to derive complete reflectance and transmittance factors for the containing layer. These complete factors in turn yield the desired irradiance fields. They are also used to develop local invariance principles and the associated local transmittance and reflectance factors. Differential equations for reflectance and transmittance are developed, based on these local factors, and in turn are used in numerical computations of the re- flectance and transmittance factors for arbitrarily deep layers of water. Boundary conditions on the upper and lower surfaces of the layer are chosen so that the complete reflectance and the complete transmittance factors generate the irradiances of the appropriate light field. Numerical computations are based on real data for eight natural media. To study the dependence of the light field on extreme cases of the optical properties, two hypothetical cases are also considered.
38

Subsemigroup structure of finite transformation semigroups.

Higgins, James Charles III 06 1900 (has links)
Both necessary conditions and sufficient conditions in order that a subset of a finite transformation semigroup be a subsemigroup are developed in this paper. The existence of several subsemigroups of various orders is established. Also, some results concerning idem- potents and generators of idempotents are proved. Then certain classes of subsemigroups are defined according to their idempotent structure and isomorphisms are demonstrated between these classes. Examples from the transformation semigroup on three elements are supplied throughout the paper
39

Nonlinear neutral functional differential equations in product spaces

Amillo-Gil, Jose M. January 1981 (has links)
Control systems governed by nonlinear neutral functional differential equations are formulated as abstract evolution equations in product spaces. At this point existence and uniqueness of solutions are studied. This formulation is used to develop a general approximation scheme for those systems. Convergence of this scheme is analyzed. It is also shown how spline based approximating methods fall within this general framework. An illustrative example is presented. / Ph. D.
40

Uniform L¹ behavior for the solution of a volterra equation with a parameter

Noren, Richard Dennis January 1985 (has links)
The solution u=u(t)=u(t,λ) of (E) u′(t)+λ∫<sub>0</sub><sup>t</sup>u(t-τ)(d+a(τ))dτ=0, u(0)=1, t ≥ 0, λ ≥ 1 where d ≥ 0, a is nonnegative, nonincreasing, convex and ∞ ≥ a(0+) > a(∞) = 0 is studied. In particular the question asked is: When is (F) ∫<sub>0</sub><sup>∞</sup><sub>λ ≥ 1</sub><sup>sup</sup>|u′′(t, λ)/λ|dt < ∞? We obtain two necessary conditions for (F). For (F) to hold, it is necessary that (-lnt)a(τ)∈L¹(0,1) and lim sup <sub>τ→∞</sub> (τθ(τ))²/φ(τ) <∞ where â(τ)=∫<sub>0</sub><sup>∞</sup>e<sup>-iτt</sup>a(t)dt=φ(τ)-iτθ(τ) (φ,θ both real). We obtain sufficient conditions for (F) to hold which involve φ and θ (See Theorem 7). Then we look for direct conditions on a which imply (F). with the addition assumption -a′ is convex, we prove that (F) holds provided any one of the following hold: (i) a(0+)<∞, (ii) 0<lim inf <sub>τ→∞</sub> τ∫<sub>0</sub><sup>1/τ</sup>sa(s)ds / ∫<sub>0</sub><sup>1/τ</sup>-sa′(s)ds ≤ lim sup <sub>τ→∞</sub> τ∫<sub>0</sub><sup>1/τ</sup>sa(s)ds / ∫<sub>0</sub><sup>1/τ</sup>-sa′(s)ds < ∞, (iii) lim <sub>τ→∞</sub> τ∫<sub>0</sub><sup>1/τ</sup>sa(s)ds / ∫<sub>0</sub><sup>1/τ</sup>a(s)ds = 0, (iv) lim <sub>τ→∞</sub> ∫<sub>0</sub><sup>1/τ</sup>-sa′(s)ds / ∫<sub>0</sub><sup>1/τ</sup>a(s)ds = 0, a²(t)/-a′(t) is increasing for small t and a²(t) / -ta′(t)∈L¹(0,∈) for some ∈>0, (v) lim <sub>τ→∞</sub> ∫<sub>0</sub><sup>1/τ</sup>-sa′(s)ds / ∫<sub>0</sub><sup>1/τ</sup>a(s)ds = 0 and τ(∫<sub>0</sub><sup>1/τ</sup> a(s)ds)³ / ∫<sub>0</sub><sup>1/τ</sup>-sa′(s)ds ≤ M < ∞ for δ ≤ τ < ∞ (some δ > 0). Thus (F) holds for wide classes of examples. In particular, (F) holds when d+a(t) = t<sup>-p</sup>, 0 < p < 1; a(t)+d = -lnt (small t); a(t)+d = t⁻¹(-lnt)<sup>-q</sup>, q > 2 (small t). / Ph. D. / incomplete_metadata

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