An Abstract Index Theorem on Non-Compact Riemannian Manifolds
Date: 1993
Creator: Anghel, Nicolae
Description: This article discusses an abstract index theorem on non-compact Riemannian manifolds. Abstract: We prove an abstract index theorem for essentially self-adjoint Fredholm supersymmetric first-order elliptic differential operators on Hermitian vector bundles over complete oriented Riemannian manifolds. According to our main result the supersymmetric L2-index of such an operator can be expressed as the sum of a "local contribution" (the familiar Atiyah-Singer index form, suitably restricted to and integrated over a finite region) and a "boundary contribution" (which depends only on the restriction of the operator at large distances). This is done by splicing together local parametrices and Green's operators defined "at infinity". The result yields (in fact is equivalent to) a generalisation of the relative index theorem of Gromov and Lawson.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc159527/
Asupra structurii grupurilor abeliene finite
Date: 2007
Creator: Anghel, Nicolae
Description: In this article, the author presents a direct elementary proof to a classical result regarding the structure of finite abelian groups as products of descending cyclic groups.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc146570/
Asupra sumelor de puteri asemenea
Date: February 2005
Creator: Anghel, Nicolae
Description: This article addresses, from a historical perspective, Newton's sums of like powers of natural numbers.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc152442/
Asupra unei probleme de loc geometric a lui A. Dafina
Date: 2003
Creator: Anghel, Nicolae
Description: This paper generalizes a certain geometric locus problem due to A. Dafina.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc146572/
Autonomous Robot Localization Using WiFi Fingerprinting
Date: April 14, 2011
Creator: Bunkley, Terrence; Wright, Alex & Namuduri, Kamesh
Description: This paper discusses autonomous robot localization using WiFi fingerprinting. Abstract: We are using widely available 802.11 wireless networks to determine the location of autonomous robots. Before a robot can accomplish a simple task such as moving to a specific coordinate, it must accurately know its current location with-in a certain degree of accuracy. Humans often take their eye sight and spatial awareness for granted. For a robot, the computational difficulty of solving the same problem becomes apparent. Our implementation creates a database of wireless signal strengths of a given area and uses the current signal strength reading within the area to find a weighted signal space distance. The "closest" point in the database should also correlate with the current position of the robot. Given the robots correct location, the authors can successfully navigate around any area with sufficient Wi-Fi coverage.
Contributing Partner: UNT Honors College
Permallink:digital.library.unt.edu/ark:/67531/metadc94281/
Continued Fractions and Sturmian Words: Discover the Power of Mathematics!
Date: April 14, 2011
Creator: Allen, Andrew & Cherry, William, 1966-
Description: This presentation discusses research on continued fractions as an alternative to decimal expansions. Abstract: Continued fractions are an alternative to decimal expansions for representing numbers. For a "random" number, if its decimal expansion is simple, its continued fraction expansion is probably complicated; conversely, if a number has a simple continued fraction, its decimal expansion usually appears random. The author's research involves examining numbers with nice patterns in both their decimal (or binary) expansions an din their continued fraction expansions. To explain this further, the authors the authors introduce some terminology: a "word" on the alphabet {0,1} is a possibly infinite string of 0's and 1's, e.g. 010101... The authors may also consider such a word as a binary decimal, e.g. 0.010101... A piece of a word is called a "subword." A word which is not periodic but still has as few subwords as possible is called a Sturmian word. The authors will explain how one can find simple patterns in the continued fraction expansions of some of these numbers.
Contributing Partner: UNT Honors College
Permallink:digital.library.unt.edu/ark:/67531/metadc93224/
Continued Fractions: Discover the Power of Mathematics!
Date: April 14, 2011
Creator: Beardslee, Jordan & Cherry, William, 1966-
Description: This presentation discusses research on predictable patterns in continued fractions and decimal expansions. Abstract: A continued fraction is a representation of a number by series of fractions inside fractions, such that the numerator of every fraction is a one. Decimal expansion is another way to express a number. Many times in mathematics when we have two different ways to write the same expression, we look for connections between the two notations. When trying to express a number, we encounter an interesting anomaly between continued fractions and decimal expansions. A randomly chosen number, with a predictable decimal pattern, will have an unpredictable continued fraction. Furthermore, a randomly chosen continued fraction, with predictable partial quotients, will have an unpredictable decimal expansion. However, there are those few exceptions, one of which the author is studying in depth. It is a binary sequence closely tied with the Fibonacci numbers, a series of numbers that often occur in nature. Through the author's research, the author hopes to find an understanding to this aforementioned anomaly and bridge continued fractions and decimals. In this presentation, the author will show where predictability lies and furthermore where there is chaos still to be settled.
Contributing Partner: UNT Honors College
Permallink:digital.library.unt.edu/ark:/67531/metadc93226/
O demonstratie directă a faptului că L1 (X, B, μ) verifică principiul tare al maximului modulului
Date: 1989
Creator: Anghel, Nicolae
Description: This paper proposes a new direct proof of the fact that L^1 verifies the strong maximum principle, i.e., any analytic map from the complex unit disk into L^1, constant in norm, must be constant.
Contributing Partner: UNT College of Arts and Sciences
Permallink:digital.library.unt.edu/ark:/67531/metadc152439/
Descriptive Set Theory: Why Should We Study It?
Date: April 14, 2011
Creator: Gilton, Thomas D. & Krueger, John
Description: In this presentation, the author will briefly introduce the subject of Descriptive Set Theory and the motivation for its study. The author will discuss the idea of a projective set and also define the mathematical notion of a "tree" as an example of a projective set. The author will conclude with a brief mention of a significant result that can be proved using the notion of a tree.
Contributing Partner: UNT Honors College
Permallink:digital.library.unt.edu/ark:/67531/metadc93250/
The Effects of Technology on Achievement in Mathematics in Middle School
Date: March 30, 2006
Creator: Rooth, Heather & Tunks, Jeanne L.
Description: This paper discusses a research study on the effect of technology on achievement in mathematics in middle school. Abstract: The literature suggests a strong positive correlation between the success of students using technology in an effective manner and improvement in standardized test scores. Using technology to teach math will improve student skills not only in math, but also in using technology as well. Unfortunately, there are three major barriers that impede progress in implementing this idea: cost, training, and technology failure. Teachers are skeptical, and rightly so, about how much progress can be made when continual updates and installations are constantly putting the technology on hold. This paper analyzes how these concepts, ideas, and problems have been discussed in the past in order to form a solid platform that will support technology in schools in the future. It will also discuss the suggestive findings of the project and how future research on this topic could be improved.
Contributing Partner: UNT Honors College
Permallink:digital.library.unt.edu/ark:/67531/metadc94276/