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Taluppfattning : En undersökning av elevers förståelse av decimaltal / Number sense : A study of students' understanding of decimal numbersAndersson, Carina January 2006 (has links)
<p>I detta examensarbete har jag studerat hur elever i år 6 tänker vid decimalform inom taluppfattningens område. Begreppet taluppfattning är ett mycket brett område där det dessutom finns många olika uppfattningar om vad som ingår i begreppet. Därför har jag fokuserat mitt arbete på övergången från heltal till decimaltal. Syftet med undersökningen är att belysa vikten av att lärare har goda matematiska och metodiska kunskaper, hur elever utvecklar sin taluppfattning och förhoppningsvis ge lite tips och idéer som kan användas i undervisningen med elever. Studien omfattar en litteraturgenomgång som behandlar begreppet taluppfattning där jag delat upp kapitlet i tre underrubriker: Vad innebär det att elever har en grundläggande taluppfattning? Hur utvecklar elever en god taluppfattning? Vilka speciella svårigheter finns vid övergången från heltal till decimaltal? Under metoddelen skriver jag om hur pilot- och huvudundersökningen gjordes innan läsaren får ta del av undersökningarnas resultat. Resultatet av undersökningen är att många elever har svårt för övergången från heltal till decimaltal. Det finns tre moment i förståelsen av positionssystemet som tycks orsaka större svårigheter och det är platssiffrans värde, multiplikation med tal mindre än ett och uppskattning av rimligheten av svaret i en beräkning. Uppsatsen innehåller också ett avsnitt om vad vi lärare kan göra för att underlätta elevers förståelse för övergången från heltal till decimaltal.</p>
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Plongement entre variétés lisses à homotopie rationnelle prèsBoilley, Christophe 08 December 2005 (has links)
Dans quelles conditions une application entre variétés différentiables est-elle homotope à un plongement lisse ? L'objet de la thèse est de
compléter les obstructions rationnelles déjà connues, de façon à réduire le problème initial de topologie différentiable à un problème de calcul
algébrique. Le théorème principal de la thèse permet de construire un plongement entre variétés lisses dans une classe d'homotopie rationnelle d'une application donnée, lorsque le problème algébrique a une solution. Plusieurs cas génériques de réalisabilité sont présentés, ainsi que des exemples mettant en évidence les nouvelles obstructions au plongement. Enfin, l'utilisation des techniques de chirurgie plongée dans le rang métastable aboutit à de nouveaux théorèmes de réalisation de plongements à cohomologie rationnelle près dans une variété fixée. / When does there exist a smooth embedding in a homotopy class of map between differentiable manifolds ? Rational homotopy theory provides computation machinery to such questions in differential topology. The purpose of this thesis is the completion of rational obstructions which prevent a map from being an embedding. More precisely, we show that a solution to the underlying algebraic problem gives rise to a smooth embedding with the same rational invariants. Several generic cases of realizability are detailed, as well as some examples which illustrate our new obstructions. We also use techniques of embedded surgery in metastable range, in order to state a theorem about realizability of an embedding up to rational cohomolgy into a fixed manifold.
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Prime ideals of the infinite product ring of p-adic integers /Sprano, Timothy E. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, 2006. / Abstract. "April 2006." Includes bibliographical references (leaf 69). Also available online in PDF format.
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Numerical Cognition in Rhesus Monkeys (Macaca mulatta)Marr, Emily Harris 15 July 2008 (has links)
Over the past few decades, researchers have firmly established that a wide range of nonhuman animals exhibit some form of numerical competence. The focus of this research was to define further the extent of numerical ability in rhesus monkeys, and specifically to determine whether the animals possess a symbolic understanding of Arabic numerals. This required examining the stimulus attributes (e.g., number vs. hedonic value) represented by the numerals, as well as the precision (e.g., absolute vs. relative) and generality of those representations. In chapters 2 and 3, monkeys were required to compare and order numerals and were rewarded with either proportional or probabilistic rewards. The results indicated that monkeys were relying on the ordinal or absolute numerical values associated with each numeral and not hedonic value or learned 2-choice discriminations. The studies in chapters 4 and 5 indicated that monkeys can use numerals to symbolize an approximate number of sequential motor responses. The study in Chapter 6 tested the generality of the monkeys’ symbolic number concept using transfer tests. The results indicated that some monkeys are able to abstract number across presentation mode, but this ability is only exhibited under limited conditions. Collectively, these studies provide evidence that rhesus monkeys view Arabic numerals as more than sign-stimuli associated with specific response-reward histories, but that numerals do not have the same precise symbolic meaning as they do for humans.
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Highly Non-Convex Crossing SequencesMcConvey, Andrew January 2012 (has links)
For a given graph, G, the crossing number crₐ(G) denotes the minimum number of edge crossings when a graph is drawn on an orientable surface of genus a. The sequence cr₀(G), cr₁(G), ... is said to be the crossing sequence of a G. An equivalent definition exists for non-orientable surfaces.
In 1983, Jozef Širáň proved that for every decreasing, convex sequence of non-negative integers, there is a graph G such that this sequence is the crossing sequence of G. This main result of this thesis proves the existence of a graph with non-convex crossing sequence of arbitrary length.
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A theoretical study of OFDM system performance with respect to subcarrier numbers and repeater output powerChang, Jui-Ta 09 June 2011 (has links)
Recent years, Orthogonal Frequency Division Multiplexing (OFDM) system gets more and more attentions for its great benefit to the optical fiber communication system for improving the transmission performance. Not only better performance in long distance transmission but also high bit-rate is attractive feature of the OFDM system. The OFDM technology has been developed for the wireless communication system, and is now used in Asymmetric Digital Subscriber Line (ADSL), ETSI Digital Audio Broadcasting (DAB), Digital Video Broadcasting (DVB), High Definition Television (HDTV), Wireless Local Area Network (WLAN) and so on.
The OFDM is extensively used in broadband wired and wireless communication systems, and it solves the problem of intersymbol interference (ISI) effectively. Actually, the OFDM is a kind of Multi-Carrier Modulation (MCM), and it is not a brand-new technology. The history of the OFDM can be traced back to 1966 when Chang of Bell Labs introduced the concept of the OFDM.
In this thesis, I will briefly introduce the background of optical fiber communication system, then, explain my motivation and the structure of this thesis.
Next, theoretical study has been conducted. For the simulation, I discuss the performance of the OFDM system related to the number of subcarriers and the erbium-doped fiber amplifier (EDFA) repeater output power. It revealed that small number of subcarriers had better transmission performance. In my study case, repeater output power of 0dBm was the optimum condition.
In addition, experimental study has been conducted. For the experiment, the waveform required for the OFDM signal generation was calculated offline, and it was realized by the Arbitrary Waveform Generator (AWG).
Finally, this thesis is concluded.
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Numerical study of vortex-induced vibration of a circular cylinderLi, Cheng-Ling 11 July 2012 (has links)
The present study aims to explore the dynamical behavior in the uniform flow by
numerical method. The theoretical model is based on transient of continuity equation and
momentum equation in CFD software: Fluent. With User Define Function¡]UDF¡^, we can
simulate the Vortex-induced vibration¡]VIV¡^under the uniform flow by numerical method
and plot the contour of amplitude and flow field under different Reynolds number. We will
identify the accurate and capable of central difference method in UDF by comparing with the
previous study. Also, we focus on whether the amplitude and flow situation will effect by
uniform flow in different degrees or not. Furthermore, this study shows how the time step
size and mesh effect the conclusion so that we could have the best choice on model.
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Parking Functions And Generalized Catalan NumbersSchumacher, Paul R. 14 January 2010 (has links)
Since their introduction by Konheim and Weiss, parking functions have evolved
into objects of surprising combinatorial complexity for their simple definitions. First,
we introduce these structures, give a brief history of their development and give a
few basic theorems about their structure. Then we examine the internal structures of
parking functions, focusing on the distribution of descents and inversions in parking
functions. We develop a generalization to the Catalan numbers in order to count
subsets of the parking functions. Later, we introduce a generalization to parking
functions in the form of k-blocked parking functions, and examine their internal
structure. Finally, we expand on the extension to the Catalan numbers, exhibiting
examples to explore its internal structure. These results continue the exploration of
the deep structures of parking functions and their relationship to other combinatorial
objects.
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On the strong law of large numbers for sums of random elements in Banach spaceHong, Jyy-I 12 June 2003 (has links)
Let $mathcal{B}$ be a separable Banach space. In this thesis, it is shown that the Chung's strong law of large numbers
holds for a sequence of independent $mathcal{B}$-valued random
elements and an array of rowwise independent $mathcal{B}$-valued
random elements under some weaker assumptions by using more
generalized functions $phi_{n}$'s.
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Gene expression analysis of Sucrose synthase1 and Shrunken1 in euploid and aneuploid maize /Cooper, Jennifer L. January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 117-121). Also available on the Internet.
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