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Application of Evolutionary Computation - Genetic Algorithm in the Unified Model Design Considerations for ACSRLiu, Hongyan 01 1900 (has links)
Aluminum Conductor Steel Reinforced (ACSR) conductors have been applied in electric power transmission and distribution for over 80 years. Research about ACSR includes its possible properties in electrical, mechanical, and thermal areas. We postulate that these properties predict certain behaviours in power transmission and distribution lines. Four models have been established by various authors for determining conductor behaviour. They are the electromagnetic, mechanical, radial conduction, and steady-state thermal models. These models were developed independently,. Although they can be used in their fields individually, there are no experimental studies verifying a combined model. Also, using them separately does not yield the required information for determining conductor performance. The unified model connects these models probabilistically by considering power system loads and meteorological factors. Based on the unified model and its modules, it is possible to use mathematical tools to optimize the ACSR design and analyze conductor characteristics when conductor parameters are changed,. Evolutionary Computation is an optimization process simulating natural evolution on the computer. Instances based on evolutionary principles are Evolutionary Algorithms that historically include Genetic Algorithms, Evolution Strategies, and Evolutionary Programming. Genetic Algorithms are used in the optimization of multi-dimensional problems in this work. Evolutionary Algorithms are empirically robust in finding near-optimal solutions to complex problems through parallel searches of solution space. Evolution Computations imitates natural evolution and genetic variation, and lays the mathematical foundation for problems in which many inputs are variable. Especially, Genetic Algorithms are extensively applied in engineering to solve problems without satisfying gradient descent, deterministic hill climbing, or purely random search. This project introduces the Evolutionary Algorithms and applies the Genetic Algorithms to the unified models. The problem solved by applying Genetic Algorithms to optimize the unified model is to select optimum multi-dimensional input parameters for the model. This provides an effective way to find conductor size for optimizing conductor design. The results give the variation of electrical, thermal, and mechanical characteristics according to conductor loss changes and predict the variation ranges of electric and magnetic fields of three-layer conductors within ASTM standards. The procedure to apply Genetic Algorithms to optimize ACSR design is unique to the problem. Objective functions are found according to the characteristics of each model. The results are put into the unified model. Comparing results gives rules to change geometrical parameters of ACSR to reach minimal Joule loss. / Thesis / Master of Engineering (ME)
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Citizens’ adoption of an electronic government system: towards a unified viewRana, Nripendra P., Dwivedi, Y.K., Lal, B., Williams, M.D., Clement, M. 25 September 2020 (has links)
Yes / Sluggish adoption of emerging electronic government (eGov) applications continues to be a problem across developed and developing countries. This research tested the nine alternative theoretical models of technology adoption in the context of an eGov system using data collected from citizens of four selected districts in the state of Bihar in India. Analysis of the models indicates that their performance is not up to the expected level in terms of path coefficients, variance in behavioural intention, or the fit indices of the models. In response to the underperformance of the alternative theoretical models to explain the adoption of an eGov system, this research develops a unified model of electronic government adoption and tests it using the same data. The results indicate that the proposed research model outperforms all alternative models of technology adoption by explaining 77 % of variance in behavioural intention, with acceptable values of fit indices and significant relationships between each pair of hypothesised factors.
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Epistemology of a theory of everything Weyl, Einstein, and the unification of physics /Fogel, D. Brandon. January 2008 (has links)
Thesis (Ph. D.)--University of Notre Dame, 2008. / Thesis directed by Don Howard for the Graduate Program in History and Philosophy of Science. "April 2008." Includes bibliographical references (leaves 212-220).
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The counterair companion short guide to air superiority for joint force commanders /Holmes, James M. January 1900 (has links)
Thesis--School of Advanced Airpower Studies, 1994. / Shipping list no.: 1998-0921-M. "April 1995." Includes bibliographical references. Also available via Internet from the Air University Press web site. Address as of 10/28/03: http://aupress.au.af.mil/SAAS%5FTheses/Holmes/holmes.pdf; current access is available via PURL.
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The Organization and Training of Joint Task ForcesWalker, Daniel R. 23 March 1998 (has links)
Thesis (M.M.A.S.)--School of Advanced Airpower Studies, 1995. / Subject: Examines the organization, training, doctrine, and experience of joint task forces within each of the five geographically tasked unified commands. Cover page date: June 1995. Vita. Includes bibliographical references.
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User Acceptance Evaluation of E-Government Services, Impact of Unified Approach Framework on the Government. Cloud Sultanate of Oman as a Case Study; Government and Citizens PerspectivesAl Shaidy, Al Noaman M.K. January 2019 (has links)
Oman has adopted e-government services, but according to the United
Nations E-Government Development Index classification, such services are
not fully utilised. E-government classification of Oman shows a lack that
motivated this research. The aim is to provide a framework that can help the
Omani government to better implement e-government services. As a result,
Oman classification is expected to be improved. Such framework may also
help similar developing countries in implementing their e-government services.
This work aimed to address both; government and citizens prospective, also
aiming to help conducting a sold research a good implementable framework.
Therefore, an interview with 21 government participations from different
institutions was conducted followed by citizens that attracted 400 qualified
responses. The research process has led to the suggestion of using another
approach of e-government services, the unified e-services portals.
The outcomes of this research show; both government and citizens are in
favour of using unified definitions in portals. In addition, a proposed framework
is presented based on supported findings that is believed to better utilising e government services hence leading to improve ranking. It is also believed that
the UN assessing committees would benefit from the unified approach. Simply,
it unifies the definition of each service based on the published academic
definitions and work.
The evaluation of the proposed framework is outside this research and can be
addressed by a further research as recommended. Implementing the unified
approach portals is another front that attracts implementation and evaluation.
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DEVELOPMENT OF GENERIC GROUND SYSTEMS BY THE USE OF A STANDARD MODELING METHODYamada, Takahiro 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper presents an approach to development of generic ground systems to be used for
spacecraft testing and operations. This method makes use of a standard modeling method, which
enables virtualization of spacecraft. By virtualizing spacecraft, development of generic systems
that are applicable to different spacecraft becomes possible even if spacecraft themselves are not
standardized. This is because systems can utilize (1) a standard database that can store
information on any virtual spacecraft and (2) standard software tools that can be used for any
virtual spacecraft. This paper explains the concept of virtualization of spacecraft, introduces the
standard model used for virtualization of spacecraft, shows how to manipulate virtual spacecraft
with software tools, and presents the core elements of generic ground systems.
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STUDENT ACHIEVEMENT IN SCHOOLS DESEGREGATED BY COURT ORDER (TESTS, READING).COLEMAN-PUCKETT, ARGENTINA. January 1986 (has links)
The purpose of this study was to determine whether, in public education, separate is inherently unequal and concomitantly, whether desegregation confers educational benefits upon all groups of students. The study investigated student achievement in schools which were placed under a court order to desegregate beginning in 1978. A mixed design, repeated measures analysis of variance (ANOVA) was utilized to investigate whether significant differences existed among various groups within the fifth-grade cohort of 212 subjects assigned to three desegregated schools. Conducted as an ex post facto investigation, the study utilized reading test scores of 1977, 1981 and 1983 extracted from the district's computerized data base. There are cautions and limitations inherent in any ex post facto research, as well as in reliance upon standardized test results as the solitary measure of student achievement, which should be kept in mind in accepting conclusions of this study. Significant differences were found among (1) racial/ethnic groups, (2) schools, (3) desegregation durations, (4) local and extended neighborhood students (LNS, ENS) and (5) school test profiles. Specific findings are that: (1) Slightly higher gains were recorded for minority students. (2) Phase III students showed significantly higher gains. (3) Highest performance was recorded for Phase I students and was attributed to the benefits of longer desegregation treatment. (4) Overall, LNS performed lower than ENS, yet in Phase III, LNS had nearly twice the gains of ENS. (5) The individual school's test profile showed a decrease during the first years of desegregation, then increased to a level which was comparable or higher than pre-desegregation levels. Keeping the aforementioned cautions in mind, the study concluded that desegregation conferred educational benefits upon all groups of students and continued to support the premise of Brown (1954) that, in public education, separate education is inherently unequal education.
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Proton decay matrix elements from lattice QCDCooney, Paul January 2010 (has links)
We present results for the matrix elements relevant for proton decay in Grand Unified Theories (GUTs), using two methods. In the indirect method, we rely on an effective field theory description of proton decay, where we need to estimate two low energy constants. We then relate these low energy constants to the proton decay matrix elements using leading order chiral perturbation theory. In the direct method, we calculate the required matrix elements directly; this is computationally more expensive, but the calculation has no systematic error from the use of chiral perturbation theory. The calculations are performed with 2+1 flavors of domain wall fermions on lattices of size 163 × 32 and 243 × 64 with a fifth dimension of length 16. We work at fixed inverse lattice spacing, a−1 = 1.73(3) GeV, leading to physical volumes of (1.8 fm)3 and (2.7 fm)3 for the 163 × 32 and 243 × 64 lattices respectively. In the first four chapters we present the background theory. We start with a brief review of the standard model and the motivation for GUTs. We show that GUTs must lead to proton decay, and that the proton lifetime is an experimentally testable prediction which can be used to constrain GUT parameters, or rule out classes of GUT which predict a minimum lifetime shorter than the experimental minimum bound. We then review continuum and lattice QCD, including outlines of the lattice methods used to calculate the proton decay matrix elements. In the last three chapters we present the results and analysis. We calculate the nucleon and pion two–point correlation functions, and determine their ground state masses and amplitudes. These quantities will then be used to calculate the matrix elements using the indirect and direct methods outlined above. The matrix elements can then be combined with experimental bounds on the proton lifetime to bound parameters of individual GUTs.
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Adaptive Java optimisation using machine learning techniquesLong, Shun January 2004 (has links)
There is a continuing demand for higher performance, particularly in the area of scientific and engineering computation. In order to achieve high performance in the context of frequent hardware upgrading, software must be adaptable for portable performance. What is required is an optimising compiler that evolves and adapts itself to environmental change without sacrificing performance. Java has emerged as a dominant programming language widely used in a variety of application areas. However, its architectural independant design means that it is frequently unable to deliver high performance especially when compared to other imperative languages such as Fortran and C/C++. This thesis presents a language- and architecture-independant approach to achieve portable high performance. It uses the mapping notation introduced in the Unified Transformation Framework to specify a large optimisation space. A heuristic random search algorithm is introduced to explore this space in a feedback-directed iterative optimisation manner. It is then extended using a machine learning approach which enables the compiler to learn from its previous optimisations and apply the knowledge when necessary. Both the heuristic random search algorithm and the learning optimisation approach are implemented in a prototype Adaptive Optimisation Framework for Java (AOF-Java). The experimental results show that the heuristic random search algorithm can find, within a relatively small number of atttempts, good points in the large optimisation space. In addition, the learning optimisation approach is capable of finding good transformations for a given program from its prior experience with other programs.
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