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Analyzing A Method To Determine The Utility Of Adding A Classification System To A Sequence For Improved Accuracy, Kevin S. Pamilagas 2019 Air Force Institute of Technology

Analyzing A Method To Determine The Utility Of Adding A Classification System To A Sequence For Improved Accuracy, Kevin S. Pamilagas

Theses and Dissertations

Frequently, ensembles of classification systems are combined into a sequence in order to better enhance the accuracy in classifying objects of interest. However, there is a point in which adding an additional system to a sequence no longer enhances the system as either the increase in operational costs exceeds the benefit of improvements in classification or the addition of the system does not increase accuracy at all. This research will examine a utility measure to determine the valid or invalid nature of adding a classification system to a sequence of such systems based on the ratio of the change in …


Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin 2019 Air Force Institute of Technology

Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin

Theses and Dissertations

In 2008, the Department of Defense published a guidebook for a methodology named Condition-Based Maintenance Plus (CBM+) which capabilities include improving productivity, shortening maintenance cycles, lowering costs, and increasing availability and reliability. This push replaces existing inspection criteria, often conducted as non-destructive testing (NDT), with structural health monitoring (SHM) systems. The SHM system addressed utilizes guided Lamb waves generated by piezoelectric wafer active sensors (PWAS) to detect the existence, size, and location of damage from through-thickness cracks around a rivet hole. The SHM field lacks an experiment testing how small changes in receiver sensor distances affect damage detection. In addition, …


Schlieren Imaging And Flow Analysis On A Cone/Flare Model In The Afrl Mach 6 Ludwieg Tube Facility, David A. Labuda 2019 Air Force Institute of Technology

Schlieren Imaging And Flow Analysis On A Cone/Flare Model In The Afrl Mach 6 Ludwieg Tube Facility, David A. Labuda

Theses and Dissertations

High-speed Schlieren photography was utilized to visualize flow in the Air Force Research Laboratory Mach 6 Ludwieg tube facility. A 7° half-angle cone/flare model with variable nosetip radius and flare angle options was used in the study. Testing was performed at two driver tube pressures, generating freestream Reynolds numbers of 10.0x106 and 19.8x106 per meter. The variable-angle flare portion of the model provided a method for adjusting the intensity of the adverse pressure gradient at the cone/flare junction. As expected from existing literature, boundary layer separation along the cone frustum occurred further upstream as the magnitude of the …


Time Series Analysis Of Stochastic Networks With Correlated Random Arcs, Brendon T. Sands 2019 Air Force Institute of Technology

Time Series Analysis Of Stochastic Networks With Correlated Random Arcs, Brendon T. Sands

Theses and Dissertations

While modern day weather forecasting is not perfect, there are many benefits given by the multitude and variety of predictive models. In the interest of routing airplanes, this paper uses time series analysis on successive weather forecasts to predict the optimal path and fuel burn of wind-based, fuel-burn networks with stochastic correlated arcs. Networks are populated with either deterministic or ensemble-based weather data, and the two data sources with and without time series analysis are compared. Methods were compared by fuel burn prediction accuracy and ability to predict a future optimal path. Of the four options, the ensemble-based methods were …


Wall Model Large Eddy Simulation Of A Diffusing Serpentine Inlet Duct, Ryan J. Thompson 2019 Air Force Institute of Technology

Wall Model Large Eddy Simulation Of A Diffusing Serpentine Inlet Duct, Ryan J. Thompson

Theses and Dissertations

The modeling focus on serpentine inlet ducts (S-duct), as with any inlet, is to quantify the total pressure recovery and ow distortion after the inlet, which directly impacts the performance of a turbine engine fed by the inlet. Accurate prediction of S-duct ow has yet to be achieved amongst the computational fluid dynamics (CFD) community to improve the reliance on modeling reducing costly testing. While direct numerical simulation of the turbulent ow in an S-duct is too cost prohibitive due to grid scaling with Reynolds number, wall-modeled large eddy simulation (WM-LES) serves as a tractable alternative. US3D, a hypersonic research …


Solving The Traveling Salesman Problem Using Ordered-Lists, Petar D. Jackovich 2019 Air Force Institute of Technology

Solving The Traveling Salesman Problem Using Ordered-Lists, Petar D. Jackovich

Theses and Dissertations

The arc-greedy heuristic is a constructive heuristic utilized to build an initial, quality tour for the Traveling Salesman Problem (TSP). There are two known sub-tour elimination methodologies utilized to ensure the resulting tours are viable. This thesis introduces a third novel methodology, the Greedy Tracker (GT), and compares it to both known methodologies. Computational results are generated across multiple TSP instances. The results demonstrate the GT is the fastest method for instances below 400 nodes while Bentley's Multi-Fragment maintains a computational advantage for larger instances. A novel concept called Ordered-Lists is also introduced which enables TSP instances to be explored …


The Systems Of Post And Post Algebras: A Demonstration Of An Obvious Fact, Daviel Leyva 2019 University of South Florida

The Systems Of Post And Post Algebras: A Demonstration Of An Obvious Fact, Daviel Leyva

USF Tampa Graduate Theses and Dissertations

In 1942, Paul C. Rosenbloom put out a definition of a Post algebra after Emil L. Post published a collection of systems of many–valued logic. Post algebras became easier to handle following George Epstein’s alternative definition. As conceived by Rosenbloom, Post algebras were meant to capture the algebraic properties of Post’s systems; this fact was not verified by Rosenbloom nor Epstein and has been assumed by others in the field. In this thesis, the long–awaited demonstration of this oft–asserted assertion is given.

After an elemental history of many–valued logic and a review of basic Classical Propositional Logic, the systems given …


Analyses Of Unorthodox Overlapping Gene Segments In Oxytricha Trifallax, Shannon Stich 2019 University of South Florida

Analyses Of Unorthodox Overlapping Gene Segments In Oxytricha Trifallax, Shannon Stich

USF Tampa Graduate Theses and Dissertations

A ciliate is a phylum of protozoa that has two types of nuclei, macronuclei and micronuclei. There may be more than one of each type of nucleus in the organism [1]. The macronucleus is the structure where protein synthesis and cell metabolism occur [1]. The micronucleus stores genetic information and is mobilized during a sexual reproduction process called conjugation [1]. The somatic macronucleus (MAC) is developed from the germ-line micronucleus (MIC) through genome rearrangement during a sexual reproduction process called conjugation [6, 8]. Segments of the MIC that form the MAC during conjugation are called macronuclear destined sequences (MDSs) [8]. …


Student-Faculty Connection And Stem Identity In The Flipped Classroom, Adrian P. Gentle, William Wilding 2019 University of Southern Indiana

Student-Faculty Connection And Stem Identity In The Flipped Classroom, Adrian P. Gentle, William Wilding

ASEE IL-IN Section Conference

Students who arrive at college intending to major in a STEM discipline are often required to complete a college-level precalculus course, despite evidence that these courses are not always successful in preparing students for calculus. The implementation of evidence-based teaching strategies, such as the flipped classroom, provides an avenue for improving the effectiveness of precalculus. This quasi-experimental study explores the effect of a flipped precalculus classroom on students' degree of connection with their instructor and other students, together with their sense of motivation and enjoyment of mathematics, which we treat as an indicator of a developing STEM identity. Validated survey …


Monoidal Supercategories And Superadjunction, Dene Lepine 2019 University of Ottawa

Monoidal Supercategories And Superadjunction, Dene Lepine

Rose-Hulman Undergraduate Mathematics Journal

We define the notion of superadjunction in the context of supercategories. In particular, we give definitions in terms of counit-unit superadjunctions and hom-space superadjunctions, and prove that these two definitions are equivalent. These results generalize well-known statements in the non-super setting. In the super setting, they formalize some notions that have recently appeared in the literature. We conclude with a brief discussion of superadjunction in the language of string diagrams.


Strengthening Relationships Between Neural Ideals And Receptive Fields, Angelique Morvant 2019 Texas A&M University

Strengthening Relationships Between Neural Ideals And Receptive Fields, Angelique Morvant

Rose-Hulman Undergraduate Mathematics Journal

Neural codes are collections of binary vectors that represent the firing patterns of neurons. The information given by a neural code C can be represented by its neural ideal JC. In turn, the polynomials in JC can be used to determine the relationships among the receptive fields of the neurons. In a paper by Curto et al., three such relationships, known as the Type 1-3 relations, were linked to the neural ideal by three if-and-only-if statements. Later, Garcia et al. discovered the Type 4-6 relations. These new relations differed from the first three in that they were …


Triangle Packing On Tripartite Graphs Is Hard, Peter A. Bradshaw 2019 University of Kansas

Triangle Packing On Tripartite Graphs Is Hard, Peter A. Bradshaw

Rose-Hulman Undergraduate Mathematics Journal

The problem of finding a maximum matching on a bipartite graph is well-understood and can be solved using the augmenting path algorithm. However, the similar problem of finding a large set of vertex-disjoint triangles on tripartite graphs has not received much attention. In this paper, we define a set of vertex-disjoint triangles as a “tratching.” The problem of finding a tratching that covers all vertices of a tripartite graph can be shown to be NP-complete using a reduction from the three-dimensional matching problem. In this paper, however, we introduce a new construction that allows us to emulate Boolean circuits using …


Graphs, Random Walks, And The Tower Of Hanoi, Stephanie Egler 2019 Baldwin Wallace University, Berea

Graphs, Random Walks, And The Tower Of Hanoi, Stephanie Egler

Rose-Hulman Undergraduate Mathematics Journal

The Tower of Hanoi puzzle with its disks and poles is familiar to students in mathematics and computing. Typically used as a classroom example of the important phenomenon of recursion, the puzzle has also been intensively studied its own right, using graph theory, probability, and other tools. The subject of this paper is “Hanoi graphs”, that is, graphs that portray all the possible arrangements of the puzzle, together with all the possible moves from one arrangement to another. These graphs are not only fascinating in their own right, but they shed considerable light on the nature of the puzzle itself. …


Asymptotically Optimal Bounds For (𝑡,2) Broadcast Domination On Finite Grids, Timothy W. Randolph 2019 Williams College

Asymptotically Optimal Bounds For (𝑡,2) Broadcast Domination On Finite Grids, Timothy W. Randolph

Rose-Hulman Undergraduate Mathematics Journal

Let G = (V,E) be a graph and t,r be positive integers. The signal that a tower vertex T of signal strength t supplies to a vertex v is defined as sig(T, v) = max(t − dist(T,v),0), where dist(T,v) denotes the distance between the vertices v and T. In 2015 Blessing, Insko, Johnson, and Mauretour defined a (t, r) broadcast dominating set, or simply a (t, r) broadcast, on G as a set T ⊆ V such that the sum of all signal received at each vertex v ∈ V from the set of towers T …


New Experimental Investigations For The 3𝑥+1 Problem: The Binary Projection Of The Collatz Map, Benjamin Bairrington, Aaron Okano 2019 University of California, Davis

New Experimental Investigations For The 3𝑥+1 Problem: The Binary Projection Of The Collatz Map, Benjamin Bairrington, Aaron Okano

Rose-Hulman Undergraduate Mathematics Journal

The 3x + 1 Problem, or the Collatz Conjecture, was originally developed in the early 1930's. It has remained unsolved for over eighty years. Throughout its history, traditional methods of mathematical problem solving have only succeeded in proving heuristic properties of the mapping. Because the problem has proven to be so difficult to solve, many think it might be undecidable. In this paper we brie y follow the history of the 3x + 1 problem from its creation in the 1930's to the modern day. Its history is tied into the development of the Cosper Algorithm, which maps binary sequences …


A Generalized Newton-Girard Identity, Tanay Wakhare 2019 University of Maryland, College Park

A Generalized Newton-Girard Identity, Tanay Wakhare

Rose-Hulman Undergraduate Mathematics Journal

We present a generalization of the Newton-Girard identities, along with some applications. As an addendum, we collect many evaluations of symmetric polynomials to which these identities apply.


The Modern Methods Of Using Alternative Energy Sources, U. Mirzayev, J. T. Tulakov Jakhongir Turakul ugl 2019 Jizzakh Polytecnic Institute

The Modern Methods Of Using Alternative Energy Sources, U. Mirzayev, J. T. Tulakov Jakhongir Turakul Ugl

Central Asian Problems of Modern Science and Education

At present, much attention is paid to the use of solar energy. Solar energy, in addition to traditional energy, is ecologically clean while changing. The rarity and the rising cost of fuel is one of the main problems of the scientific technique, which is the acquisition of infinite resources of solar energy. Further research and experiments on the use of solar energy, as well as the use of solar power plants in a number of countries, shows that solar energy can be widely used today based on modern technical capacities


Research Of Processes Of Implantation Of Ions In Monocrystal Gaas (001) On Purpose Increase In Efficiency Of Solar Elements, I. I. Khafizov, K. K. Gafforov 2019 Bukhara Engineering and Technological Institute

Research Of Processes Of Implantation Of Ions In Monocrystal Gaas (001) On Purpose Increase In Efficiency Of Solar Elements, I. I. Khafizov, K. K. Gafforov

Central Asian Problems of Modern Science and Education

On purpose increase efficiency of solar elements it has been investigated process of ionic implantation influencing the big number of the interconnected coefficients, most important of which is target orientation, a grade, initial energy and a corner of falling of primary particles


Basic Parameters Of Physical Properties Of The Saline Soils In Roadside Of Highways, A. D. Kayumov Abdubaki Djalilovic, O.Z. Zafarov, N. D. Saidbaxromova 2019 Jizzakh Polytechnic Institute

Basic Parameters Of Physical Properties Of The Saline Soils In Roadside Of Highways, A. D. Kayumov Abdubaki Djalilovic, O.Z. Zafarov, N. D. Saidbaxromova

Central Asian Problems of Modern Science and Education

This article provides information about the basic parameters of physical properties of the saline soils in roadside of highways, the key and rational indicators which are determined by the experiments and by calculating respectively in the evaluation of soil physical states, the density of solid particles, the basic parameters of density and moisture of the soil in natural condition


The First Stages Of Communication Service Formation In Uzbekistan (In The Case Of Khorezm), I. S. Yusupov 2019 Urganch branch of Tashkent University of Information Technology named after Muhammad al-Khorezmi

The First Stages Of Communication Service Formation In Uzbekistan (In The Case Of Khorezm), I. S. Yusupov

Central Asian Problems of Modern Science and Education

This article describes the emergence and development of communication services in ancient times in Khorezm, northwest of Uzbekistan


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