Os principais objetos de estudo neste trabalho são os números de Ramsey para circuitos e o lema da regularidade de Szemerédi. Dados grafos $L_1, \\ldots, L_k$, o número de Ramsey $R(L_1,\\ldots,L_k)$ é o menor inteiro $N$ tal que, para qualquer coloração com $k$ cores das arestas do grafo completo com $N$ vértices, existe uma cor $i$ para a qual a classe de cor correspondente contém $L_i$ como um subgrafo. Estaremos especialmente interessados no caso em que os grafos $L_i$ são circuitos. Obtemos um resultado original solucionando o caso em que $k=3$ e $L_i$ são circuitos pares de mesmo tamanho. / The main objects of interest in this work are the Ramsey numbers for cycles and the Szemerédi regularity lemma. For graphs $L_1, \\ldots, L_k$, the Ramsey number $R(L_1, \\ldots,L_k)$ is the minimum integer $N$ such that for any edge-coloring of the complete graph with~$N$ vertices by $k$ colors there exists a color $i$ for which the corresponding color class contains~$L_i$ as a subgraph. We are specially interested in the case where the graphs $L_i$ are cycles. We obtained an original result solving the case where $k=3$ and $L_i$ are even cycles of the same length.

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This project's purpose was to understand the workings of a new theorem introduced in a professional paper on the cutwidth of meshes and then use this knowledge to apply it to the search for the cyclic cutwidth of the n-cube.

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Lean construction is considered a valuable solution for the declining productivity of the construction industry. This study seeks to answer the general research question: What does it take to become lean? The research explored the possible paths to becoming lean by examining the journeys of three successful lean construction firms in the U.S. The results are intended to assist other construction firms with their own transformations. This study is especially useful to executives and management because it describes the cultural transformation process of each participating company, the expectations of company employees, and the best practices that each company employed. A qualitative, multiple-case study methodology was used to find common patterns among all three firms as well as unique attributes. Eight research themes shaped the interview dialog that probed the participants’ experiences and insights regarding lean— from the companies’ initial discovery of lean to their implementation of tools and trainings. The themes further prompted responses regarding the roles that were critical to successful lean implementation as well as the barriers that inhibited lean adoption. Finally, interviews also sought out strategies to successfully promote and implement lean into the future. The research discusses the assertions and conclusions that emerged from the findings, which identify several successful paths to becoming lean. Findings show how people, the environment, and actions positively or negatively influence the adoption of a lean culture. The study concludes with recommendations for future firms regarding lean planning to transform the organization into a successful, top-performing, lean construction company. It emphasizes personalized application for each employee to create a positive environment for the new culture to develop. The conclusions also include five phases of lean saturation: discovery and learning, commitment, strategic planning, implementation, and training company partners in lean.

Power systems will increasingly rely on synchrophasor systems for reliable and high-performance wide area monitoring and control (WAMC). Synchrophasor systems greatly use information communication technologies (ICT) for data exchange which are vulnerable to cyber-attacks. Prior to installation of a synchrophasor system a set of cyber security requirements must be developed and new devices must undergo vulnerability testing to ensure that proper security controls are in place to protect the synchrophasor system from unauthorized access. This dissertation describes vulnerability analysis and testing performed on synchrophasor system components. Two network fuzzing frameworks are proposed; for the I C37.118 protocol and for an energy management system (EMS). While fixing the identified vulnerabilities in information infrastructures is imperative to secure a power system, it is likely that successful intrusions will still occur. The ability to detect intrusions is necessary to mitigate the negative effects from a successful attacks. The emergence of synchrophasor systems provides real-time data with millisecond precision which makes the observation of a sequence of fast events feasible. Different power system scenarios present different patterns in the observed fast event sequences. This dissertation proposes a data mining approach called mining common paths to accurately extract patterns for power system scenarios including disturbances, control and protection actions and cyber-attacks from synchrophasor data and logs of system components. In this dissertation, such a pattern is called a common path, which is represented as a sequence of critical system states in temporal order. The process of automatically discovering common paths and building a state machine for detecting power system scenarios and attacks is introduced. The classification results show that the proposed approach can accurately detect these scenarios even with variation in fault locations and load conditions. This dissertation also describes a hybrid intrusion detection framework that employs the mining common path algorithm to enable a systematic and automatic IDS construction process. An IDS prototype was validated on a 2-line 3-bus power transmission system protected by the distance protection scheme. The result shows the IDS prototype accurately classifies 25 power system scenarios including disturbances, normal control operations, and cyber-attacks.

This study is an examination of whether a project-based mathematics curriculum would influence students' intended career paths related to science, technology, engineering, and mathematics (STEM) endeavors; perceived usefulness of mathematics; and perceived competence in doing mathematics. A review of the literature revealed that there are many shortages of professionals in STEM fields. United States women and men are not pursuing STEM endeavors in great numbers and the U.S. relies heavily on international students to fill this gap. The literature revealed that the girls who do not pursue STEM endeavors in great numbers do not perceive mathematics as a useful endeavor and do not think they are competent in doing mathematics. Boys who do not pursue STEM endeavors in great numbers also do not perceive mathematics as a useful endeavor. The study involved 7th and 8th grade school students enrolled in algebra classes in a private college-preparatory school. The students in the experimental group participated in a problem-based curriculum that integrated lecture-based methods with four major projects designed to have students apply mathematics out of the context through hands-on real-life problems. This particular quasi-experimental design was a nonequivalent pre-test/post-test control group design. Statistical analyses were done using a general linear model repeated measures. The results of the statistical analyses indicated that the students in the project-based group showed a statistically significant positive change in their perceived usefulness of mathematics when compared to the control group. A t-test revealed no statistically significant differences in academic achievement. Qualitative data analysis uncovered three emergent themes. Students indicated that they saw the usefulness of mathematics more clearly; students' independence from the teacher while doing the projects was unsettling; and students enjoyed the change of pace in class. The results of the study indicated that a project-based mathematics curriculum can help students see the usefulness of mathematics and can help students enjoy the pursuit of mathematics by this particular change of routine.

The Geographic Information System (GIS) is a crucial part of any land navigation system. Autonomous ground vehicles should have access to stored geographic data and the ability to manipulate it for routing purposes. Since there is no human interaction involved in operating these vehicles, data that a human driver would use to make decisions must be stored in the GIS. The data which represent the earth's surface become a series of factors and constraints which translate to friction in terms of mobility. Factors need to be weighted appropriately, but require a sensitivity analysis before designating these weights. Constraints do not require any weight because they represent absolute barriers which cannot be traveled upon. All GIS layers are incorporated into the raster environment, so that an accumulated surfaces can be built on which a least-cost path can be located. The sensitivity analysis allows generation of many routes which can be field tested for the appropriate weight selection for each factor. Ultimately, the entire process would select an optimal path and output closely spaced waypoints which the vehicle can follow. / Master of Science

The purpose of the study was to explore the lived experiences of exemplary female elementary principals. The qualitative phenomenological study investigated the career paths, job responsibilities, barriers/challenges, and affirmations of exemplary female principals practicing in elementary schools in the United States. The participants were required to have at least 5 years of experience in education and at least 3 years as an elementary school principal. Interviews were conducted by the researcher to acquire explanations about the participants’ perceptions, perspectives, and feelings based on their experiences as exemplary elementary principals. The investigation focused on the females’ career paths, job responsibilities, barriers/challenges, and affirmations as exemplary leaders. Further, the females provided advice and guidance for aspiring female leaders in education. In general, the exemplary female principals started their careers as teachers, married, had children, and obtained advanced degrees and training in educational leadership as they moved to positions as elementary principals. The job responsibilities of the female principals included supervising instruction to improve instructional practices as the instructional leader, monitoring data, implementing policies and procedures, hiring as well as placing personnel, preparing budgets, maintaining a safe environment for students and staff, managing facilities, and purchasing equipment/resources for the organization. The major barriers/challenges faced by the female principals were lacking resources, managing time, prioritizing tasks, and managing tasks for work and home. Advice and guidance for aspiring female administrators centered around the personal, professional, and public service responsibilities that contributed to their success and recognition as exemplary principal.