The construction of characteristic classes via the curvature form of a connection is one motivation for the refinement of integral cohomology by de Rham cocycles -- known as differential cohomology. We will discuss the analog in the case of a group action on the manifold: We will show the compatibility of the equivariant characteristic class in integral Borel cohomology with the equivariant characteristic form in the Cartan model. Motivated by this understanding of characteristic forms, we define equivariant differential cohomology as a refinement of equivariant integral cohomology by Cartan cocycles.

Motivated by the reservoir engineering concept of the productivity index of a producing oil well in an isolated reservoir, we analyze a time dependent functional, diffusive capacity, on the solutions to initial boundary value problems for a parabolic equation. Sufficient conditions providing for time independent diffusive capacity are given for different boundary conditions. The dependence of the constant diffusive capacity on the type of the boundary condition (Dirichlet, Neumann or third-type boundary condition) is investigated using a known variational principle and confirmed numerically for various geometrical settings. An important comparison between two principal constant values of a diffusive capacity is made, leading to the establishment of criteria when the so-called pseudo-steady-state and boundary-dominated productivity indices of a well significantly differ from each other. The third type boundary condition is shown to model the thin skin effect for the constant wellbore pressure production regime for a damaged well. The questions of stabilization and uniqueness of the time independent values of the diffusive capacity are addressed. The derived formulas are used in numerical study of evaluating the productivity index of a well in a general three-dimensional reservoir for a variety of well configurations.

Dėl socialinės bei kultūrinės kaitos sąlygojamų uždavinių, visuomenėje įsitvirtina nauji paradigminiai požiūriai: mokymasis visą gyvenimą, novatoriškos mokymosi aplinkos ir kt. Tokiomis sąlygomis mokytojas, rūpindamasis jaunesniojo mokyklinio amžiaus vaiko kompetencijų ugdymu kaip autonomiškumo pagrindu B. Bitino teigimu (2005) turėtų suprasti, kad asmenybės raidą lemia ne tik visuomenė ir nuo jos nepriklausančios jėgos, bet ir ugdytinio vidinių galių skatinimas ir plėtojimas, grindžiamas pedagogo profesinėmis kompetencijomis. / Due to the tasks influenced by the social and cultural change in the society, new paradigmatic view such as life long learning, innovative teaching and learning environment , etc. are becomig stronger. As s result, the teacher taking care of the development of the primary school pupil`s skills as autonomuos basic (according to B. Bitinas statement (2005)) has to understand that the maturity of a person is determined not only by the society or independed powers but also by encouragement and broadening person`s inner stregth, which is based on the teacher`s personal competences.

The current design procedure for cantilever structures on spread footings in the Texas Department of Transportation (TxDOT) is based on horizontal pressure that is calculated by using Rankine's and Coulomb's theory. These are classical Geotechnical Engineering methods. Horizontal earth pressure due to moisture and volume change in high plasticity soil is not determined by these classical methods. However, horizontal pressure on most of the cantilever retaining structures in Texas is determined by following the classical methods. In recent years, a number of consultants have considered the horizontal pressure due to swelling on cantilever retaining structures in Texas. However, the proposed horizontal pressure by consultants is 10-20 times higher than the classical horizontal pressure. This method of cantilever retaining structure design without knowing the real pressure and stress pattern increases the thickness of the wall, and raises the cost of construction. This study focuses on providing adequate patterns of lateral earth pressure distribution on cantilever retaining structures in expansive soil. These retaining wall structures are subject to swelling pressures which cause horizontal pressures that are larger than the classical especially near the ground surface. Beside the prediction of lateral earth pressure distribution, the relations between water content, volume change and suction change are determined. Based on the laboratory testing program conducted, Soil Water Characteristic Curves (SWCC) are determined for a site located at the intersection of I-35 and Walters Street in San Antonio, Texas. Additionally, relations between volume change with confining pressure curve, water content change with the change of confining pressure curve, water content change with change of matric suction and volume change with change of matric suction curves are generated based on laboratory tests. There are a number of available mass volume measurement methods that use mostly mercury or paraffin to obtain volume measurements. Although these methods are reported in the literature, they are not used in practice due to application limitations like safety, time, and cost. In order to overcome these limitations, a new method was developed to measure the volume of soil mass by using sand displacement. This new method is an inexpensive, safe, and simple way to measure mass volume by Ottawa sand.

The theory of electromagnetic characteristic modes was published roughly forty years ago, for both conducting and penetrable objects. However, while the characteristic mode analysis of conducting objects has found renewed interest as a tool for antenna designers, computed results for the characteristic mode eigenvalues, eigencurrents and eigenfields for penetrable objects have not appeared, not even in the seminal papers on the subject. In this thesis both volume and surface integral equation formulations are used to compute the characteristic modes of penetrable objects for what appears to be the first time. This opens the way for the use of characteristic mode theory in the design of antennas made of penetrable material whose polarization current densities constitute the main radiating mechanism of the antenna. Volume formulations are shown to be reliable but computationally burdensome. It is demonstrated that surface formulations are computationally more efficient, but obtrude some non-physical modes in addition to the physical ones. Fortunately, certain field orthogonality checklists can be used to provide a straightforward means of unambiguously selecting only the physical modes. The sub-structure characteristic mode concept is extended to problems involving both perfectly conducting and penetrable materials. It is also argued that sub-structure modes can be viewed as characteristic modes that implicitly use modified Green’s functions, but without such Green’s functions being needed explicitly. This makes the concept really practical, since the desired modified Green’s functions are not known explicitly in most cases.

No description available.

Composite insulators are widely being used in power industry to alternate traditional porcelain-based insulators for their advantages, including better pollution performance, low maintenance cost, light weight, compact line design. However, due to the short application history and experience, the degradation of composite insulators in natural environment is a big concern for the power utilities. The knowledge on the degradation of composite insulators is being studied world wide. The methods to assess the working conditions of composite insulators are being studied and created. In Queensland University of Technology (QUT), the approach based on chemical analysis methods was first developed. The work in this thesis based on the previous research work is focused on correlating electrical characteristics with chemical analysis results of the composite insulators and physical observations results. First,the electrical characteristics of composite insulators were presented and analysed, including leakage current, cumulative current, peaks of leakage current, the statistic results of the leakage current. Among them, the characteristics of leakage current were mainly studied. The shape of waveforms was found to relate to the degree of discharge activities of the composite insulators. The waveforms analysed by FFT revealed that the odd harmonic components became obvious during the discharge activities. The correlations between the electrical characteristics of composite insulators and chemical analysis results showed that the composition of composite insulators plays significant roles in terms of electrical performance. The oxidation index (O.I.) and the ester/ketone ratio (E/K) differentiated the different degradation reasons of the composite insulators in the test conditions. Finally, the thesis presents one approach, which aims to assess the surface conditions of composite insulators in an easy manner and in short time.

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abstract: In this thesis, an issue is post at the beginning, that there is limited experience in connecting a battery analytical model with a battery circuit model. Then it describes the process of creating a new battery circuit model which is referred to as the kinetic battery model. During this process, a new general equation is derived. The original equation in the kinetic battery model is only valid at a constant current rate, while the new equation can be used for not only constant current but also linear or nonlinear current. Following the new equation, a circuit representation is built based on the kinetic battery model. Then, by matching the two sets of differential equations of the two models together, the ability to connect the analytical model with the battery circuit model is found. To verify the new battery circuit model is built correctly, the new circuit model is implemented into PSpice simulation software to test the charging performance with constant current, and Matlab/Simulink is also employed to simulate a realistic battery charging process with two-stage charging method. The results have shown the new circuit model is available to be used in realistic scenarios. And because the kinetic battery model can describe different types of rechargeable batteries, the new circuit model is also capable to be used for various battery types. / Dissertation/Thesis / M.S. Electrical Engineering 2012

A complex adaptive systems approach has been permeating organizational studies and the field of supply network management helping to describe and explain supply network dynamics and emergent inter-firm structures. This has improved our theoretical knowledge of the nature of supply networks transforming raw materials into products, within a constantly changing environment. From the early days of simple structures, describing bi-lateral, local arrangements between firms for the creation of relatively simple products, we are now in an environment of various supply network archetypes, describing different global sourcing regimes of highly integrated, sophisticated products within multi-tier networks. This thesis is a study of the coevolution of the firm and supply network in the commercial aerospace manufacturing sector producing jetliners of 100 or more seats. One of the contributions of this research is to demonstrate how the holistic approach of complexity science can be applied to describe, understand and gain new insight into the coevolution of the firm and the supply network. Based on the findings of multiple interviews and questionnaires in eight global aerospace firms across multiple supply chain tiers, this research finds high-performing clusters of inter-firm characteristics, plus the aspects of structure and integration which deliver the supply network performance. Practitioners can use these specific results to examine their own firms and the new coevolutionary conceptual framework developed in the thesis may aid future research studies of complex adaptive systems in practice. The simple survey design and analysis method used in the final research stage of this research, has the potential for use in other industries, markets and other complex adaptive systems generally to examine performance outcomes and the effects of having or adopting new inter-firm characteristics. Finally, implications for policy include the potential to legitimize supply networks in order to stimulate competition and innovation in the economy.