Tyrimo objektas. Epigėjinių vabalų bendrijos Kamšos botaniniame-zoologiniame draustinyje, 458 kvartale, 5 sklype. Norėdami nustatyti ekspozicijos vietų reljefo įtaką epigėjinių vabalų individų ir rūšių gausai, pasirinkome 5 tyrimų barelius, esančius lygioje miško vietoje ir šiauriniame, pietiniame, rytiniame bei vakariniame šlaituose. Tikslas - nustatyti epigėjinių vabalų bendrijų struktūrą ir jos pokyčius vegetacijos eigoje bei priklausomai nuo ekspozicijos vietų reljefo. Darbo metodai. Tyrimui buvo naudojama Barberio žemės gaudyklės. Gaudyklę sudaro plastikiniai 0,5 l talpos ir 6,5 cm skersmens indeliai, įkasti į žemę sulig paklotės paviršiumi. 1/3 gaudyklės buvo pripilama 10% formalino tirpalo. Tai apsaugojo epigėjinius vabalus nuo puvimo ir vabzdžialesių paukščių. Kiekviename barelyje buvo įrengta po 5 gaudykles, iš viso 25 gaudyklės. Atstumas tarp gaudyklių buvo 5 metrai. Surinkti epigėjiniai vabalai buvo džiovinami ir identifikuojami ASU laboratorijose. Darbo rezultatai. 2012 m. gegužės – rugpjūčio mėnesiais buvo atlikta 10 apskaitų, iš viso surinkta 1627 vnt. epigėjinių vabalų. Indenfikuotos 4 rūšys: Carabidae, Silphidae, Curculionidae, Staphylinidae ir 15 rūšių. Gausiausia iš sugautų rūšių buvo Phosphuga atrata – 312 vabalų. Lyginant sugautų vabalų skaičių skirtingo reljefo sklypo vietose, nustatyta, kad daugiausia epigėjinių vabalų sugauta lygioje miško vietoje įrengtomis gaudyklėmis. Antroje vietoje - vakariniam šlaite... [toliau žr. visą tekstą] / Study object. The research of ground beetles Insecta: Coleoptera was made in Kamša botanical-zoological reserve, 458-th section, 5-th plot. We have chosen 5 parts of the plot for investigation: in a plane surface of the forest, on the North, the South the East and the West slopes in order to detect influence of the exposition place relief to abundance of caught ground beetles individuals and species. The aim of investigation was to determine structure of ground beetle communities, its temporal changes and dependence on the relief of exposition place. Methods of investigation. The Barberis ground traps were used in the research, 5 units in the each chosen part, 25 in total. The distances between the ground traps were 5 m. The trap is made from a 0,5 l volume and 6,5 cm diameter plastic cruet. The traps were digged in to ground to the top of the trap. 1/3 of the trap was filled with a 10% formalin soak. In that case the insects were saved from decomposing and birds. The collected beetles were dried and identified in the labs of Aleksandras Stulginskis University. Results. The total amount of collected ground beetles in 10 records, made since May to August 2012, was 1627. A variety of 15 species in 4 families Carabidae, Silphidae, Curculionidae, Staphylinidae were identified. The most abundant species collected was Phosphuga atrata – 312 ground beetles. The maximum quantity of ground beetles were caught in the plane surface of the forest, the... [to full text]

Earthquake is undoubtedly one of the greatest natural disasters that can induce serious structural damage and huge losses of properties and lives. The resulting destructive consequences not only have made structural seismic analysis and design much more important but have impelled the necessity of more realistic representation of ground motions, such as inclusion of ground motion spatial variations in earthquake modelling and seismic analysis and design of structures. Recorded seismic ground motions exhibit spatial variations in their amplitudes and phases, and the spatial variabilities have an important effect on the responses of structures extended in space, such as long span bridges. Because of the multi-parametric nature and the complexity of the problems, the development of specific design provisions on spatial variabilities of ground motions in modern seismic codes has been impeded. Eurocode 8 is currently the only seismic standard worldwide that gives a set of detailed guidelines to explicitly tackle spatial variabilities of ground motions in bridge design, providing both a simplified design scheme and an analytical approach. However, there is gap between the code-specified provisions in Eurocode 8 and the realistic representation of spatially varying ground motions (SVGM) and the corresponding stochastic vibration analysis (SVA) approaches. This study is devoted to bridge this gap on modelling of SVGM and development of SVA approaches for structures extended in space under SVGM. A complete and realistic SVGM representation approach is developed by accounting for the incoherence effect, wave-passage effect, site-response effect, ground motion nonstationarity, tridirectionality, and spectra-compatibility. This effort brings together various aspects regarding rational seismic scenarios determination, comprehensive methods of accounting for varying site effects, conditional modelling of SVGM nonstationarity, and code-specified ground motion spectra-compatibility. A comprehensive, systematic, and efficient SVA methodology is derived for long span structures under tridirectional nonstationary SVGM. An absolute-response-oriented scheme of pseudo-excitation method and an improved high precision direct integration method are proposed to reduce the enormous computational effort of conventional nonstationary SVA. A scheme accounting for tridirectional varying site-response effect is incorporated in the nonstationary SVA scheme systematically. The proposed highly efficient and accurate SVA approach is implemented and verified in a general finite element analysis platform to make it readily applicable in SVA of complex structures. Based on the proposed SVA approach, parametric studies of two practical long span bridges under SVGM are conducted. To account for spatial randomness and variability of soil properties in soil-structure interaction analysis of structures under SVGM, a meshfree-Galerkin approach is proposed within the Karhunen-Loeve expansion scheme for representation of spatial soil properties modelled as a random field. The meshfree shape functions are proposed as a set of basis functions in the Galerkin scheme to solve integral equation of Karhunen-Loeve expansion, with a proposed optimization scheme in treating the compatibility between the target and analytical covariance models. The accuracy and validity of the meshfree-Galerkin scheme are assessed and demonstrated by representation of covariance models for various homogeneous and nonhomogeneous spatial fields. The developed modelling approaches of SVGM and the derived analytical SVA approaches can be applied to provide more refined solutions for quantitatively assessing code-specified design provisions and developing new design provisions. The proposed meshfree-Galerkin approach can be used to account for spatial randomness and variability of soil properties in soil-structure interaction analysis.

The objective of the proposed research is to develop structural changes to the design and application of electromagnetic (EM) sensing models to more efficiently and accurately invert EM measurements to extract parameters for applications such as landmine detection. Two different acquisition modalities are addressed in this research: ground-penetrating radar (GPR) and electromagnetic induction (EMI) sensors. The models needed for practical three-dimensional (3D) spatial imaging typically become impractically large, with up to seven dimensions of parameters that need to be extracted. These parameters include, but are not limited to target type, 3D location, and 3D orientation. The new special structures for these models exploit properties such as shift invariance and tensor representation, which can be combined with strategic inversion techniques, including the Fast Fourier Transform and semidefinite programming. The structures dramatically reduce the amount of computation and can eliminate the need to store up to five dimensions of parameters while still accurately estimating them.

In recent years, scientific studies are carried out to find new refractory material. Having good mechanical properties under very high temperatures, refractories are widely used in industries like iron, steel, glass, cement and pottery. Researches are focused on monolithic refractory making because of their superior properties comparing to conventional firebrick refractories. Providing a mono-block body, having no joints makes the monolithic refractories more durable at elevated temperatures. Easier production and installation are two main points that people are choosing monolithic refractories, thus an economy is made. In this study, for monolithic refractory production, high alumina cement was used as binding material. It is known that the increase in alumina (Al2O3) content increases the high temperature resistance, so that crushed firebrick, having 85% Al2O3 was used as aggregate. Pozzolanic materials, which are silica fume, fly ash, ground granulated firebrick and ground granulated blast furnace slag, were added to improve physical and mechanical properties of mortar. With the addition of steel fibres, change in compressive strength and flexural strength was observed.Superplasticizer was used to understand its behaviour under high temperatures. Portland cement containing mortars were also prepared to make comparison with high alumina cement containing specimens. Specimens were prepared in 5x5x5 cm and 4x4x16 cm prisms. They were cured for one day at curing room, then heated to 105&deg / C and then heated to 1100&deg / C. Weight, size and ultrasound velocity change, compressive strength and flexural strength tests were done to determine physical and mechanical properties of the monolithic refractories, before and after heating. Heated and non-heated specimens were pulverized for microstructural investigation with X-Ray diffraction (XRD) method. Using high alumina cement with 50 &ndash / 60 % granulated blast furnace slag or granulated firebrick, by the weight of cement, and crushed firebrick as aggregate, a satisfactory monolithic refractory material was made. It was observed that, mechanical properties were decreased at the Portland cement used mortars after several times of heating and cooling cycles. Also, it was determined that the microstructure of the high alumina cement containing mortars did not deteriorate much at 1100&deg / C, as long as there was no change observed from the results.

A quantitative understanding of ground water flow characteristics in unconfined aquifers is important because of the prevalence of abstraction from, and pollution of these systems. The current understanding of ground water flow in unconfined aquifers is limited because of the dominance of horizontal flow modelling strategies used to represent unconfined flow processes. The application of horizontal flow principles leads to an ignorance of seepage-face formation and can not predict the complicated three-dimensional nature of the ground water flow that dominates at the ground water-surface water interface. This study aims to address some of these deficiencies by exploring the true three-dimensional nature of ground water flow including the formation of seepage faces at the ground water-surface water interface using numerical and laboratory techniques. A finite element model for simulating two-dimensional (vertical) variably saturated flow is developed and benchmarked against standard laboratory and field-scale solutions. The numerical features of the finite element model are explored and compared to a simple finite difference formulation. The comparison demonstrates how finite element formulations lead to a broader spatial averaging of material properties and a different method for the representation of specified flux boundaries. A detailed comparison analysis indicates that these differences in the finite element solution lead to an improved approximation to the partial differential equation governing two-dimensional (vertical) variably saturated flow. A laboratory analysis of unconfined ground water flow and associated solute transport characteristics was performed. The analysis focused upon unconfined flow towards a pumping well. The laboratory observations were reliably reproduced using a three-dimensional (axi-symmetric), variably saturated ground water flow model. The model was benchmarked against the ground water flow characteristics such as the seepage-face height and total flow rate. In addition, the model was shown to reliably reproduce the solute transport features such as travel times and streamline distributions. This is the first time that a numerical model has been used to reliably reproduce the solute transport characteristics near a seepage-face boundary where the three-dimensional flow effects are prevalent. The ability to reliably predict solute transport patterns in the seepage-face zone is important since this region is known to support vital microbially facilitated reactions that control nutrient cycling and contaminant attenuation. The three-dimensional travel time distribution near the seepage-face was compared to that predicted using a horizontal flow modelling approach derived from the basic Dupuit-Forchheimer equations. The Dupuit-Forchheimer based model indicated that horizontal flow modelling would under-estimate the total residence time near a seepage-face boundary, thereby introducing a considerable source of error in a solute transport analysis. For this analysis, a new analytical solution for the steady travel time distribution in an unconfined aquifer subject to a single pumping well was derived. The analytical model has identified, for the first time in the hydrogeology literature, the use of the imaginary error function. The imaginary error function is a standard transcendental function and an infinite series approach to evaluate the function was successfully proposed. The two-dimensional (vertical) ground water flow model was extended to handle the case where the flow is driven by density gradients near the ground water-surface water interface. The unsteady, two-dimensional, Galerkin finite element model of density-dependent ground water flow in variably saturated porous media is rigorously presented and partially benchmarked under fully saturated (confined) conditions. The partial benchmarking involved reproducing solutions to the standard Henry salt-water intrusion and the Elder salt-convection problems. The model was used in a standard density-coupled and a new density-uncoupled mode to elucidate the worthiness of the Henry and Elder problems as benchmark standards. A comparison of the coupled and uncoupled solutions indicates that the Henry salt-water intrusion problem has limited worthiness as a benchmark as the patterns of ground water flow are relatively insensitive to density-coupled effects. Alternatively, the Elder problem is completely dependent upon a correct representation of the density-coupled flow and solute transport processes. The coupled versus uncoupled comparison is proposed as a new test of the worthiness of benchmark standards. The Henry salt-water intrusion problem was further analysed in an attempt to alleviate some of the difficulties associated with this benchmark problem. The numerical model was tested against a re-evaluated version of Henry's semi-analytical solution for the coupled solute concentration distribution. The numerical model was used to propose a modified version of the Henry problem where the importance of density-coupled processes was increased. The modified problem was shown to have an improved worthiness as compared to the standard solution. The numerical model results were benchmarked against a new set of semi-analytical results for the modified problem. Certain advantages in using the modified problem as a test case for benchmarking the results of a numerical model of density-dependent ground water flow are identified. A numerical investigation of the patterns of density-driven ground water flow at the ground water-surface water interface was undertaken. The numerical model is shown to produce grid-independent results for a finely discretised domain. The pattern of discharge is controlled, in part, by two parameters. One describes the recharge applied to the aquifer, and the second describes the magnitude of the density differences between the fresh recharging fluid and the saline receiving fluid. The influence of dense intrusions upon the formation of seepage-face boundaries at the ground water-surface water interface under steady-state conditions was also investigated. Dense intrusions are shown to dominate the pattern of ground water flow only under mild recharge conditions, while seepage faces dominate the outflow pattern under strong recharge conditions. Therefore, the formation of seepage-face boundaries and dense intrusions are unlikely to coincide under the conditions examined in this study.

Made available in DSpace on 2014-12-17T14:08:40Z (GMT). No. of bitstreams: 1 PedroHCF_DISSERT.pdf: 3177377 bytes, checksum: aee262ba866eb8f7862d4fdf2b03cfdf (MD5) Previous issue date: 2010-08-07 / In geophysics there are several steps in the study of the Earth, one of them is the processing of seismic records. These records are obtained through observations made on the earth surface and are useful for information about the structure and composition of the inaccessible parts in great depths. Most of the tools and techniques developed for such studies has been applied in academic projects. The big problem is that the seismic processing power unwanted, recorded by receivers that do not bring any kind of information related to the reflectors can mask the information and/or generate erroneous information from the subsurface. This energy is known as unwanted seismic noise. To reduce the noise and improve a signal indicating a reflection, without losing desirable signals is sometimes a problem of difficult solution. The project aims to get rid of the ground roll noise, which shows a pattern characterized by low frequency, low rate of decay, low velocity and high amplituds. The Karhunen-Lo?ve Transform is a great tool for identification of patterns based on the eigenvalues and eigenvectors. Together with the Karhunen-Lo?ve Transform we will be using the Singular Value Decomposition, since it is a great mathematical technique for manipulating data / Na geof?sica existem diversas etapas no estudo da Terra, uma delas ? o processamento de registros s?smicos. Esses registros s?o obtidos atrav?s de observa??es realizadas na superf?cie, sendo ?teis para informa??es sobre a estrutura e a composi??o das zonas inacess?veis em grandes profundidades. Grande parte das ferramentas e t?cnicas desenvolvidas para tais estudos tem sido aplicada em pesquisas acad?micas. O grande problema do processamento s?smico ? a energia indesejada, registrada pelos receptores que n?o trazem nenhum tipo de informa??o em rela??o aos refletores podendo mascarar as informa??es e/ou gerar informa??es erradas da subsuperf?cie. Essa energia indesejada ? conhecida como ru?do s?smico. Atenuar esse ru?do para melhorar um sinal que indica uma reflex?o, sem perder sinal desej?vel ? algumas vezes um problema de dif?cil solu??o. O projeto tem como objetivo a atenua??o do ru?do ground roll , o qual apresenta um padr?o caracterizado pela baixa freq??ncia, baixa velocidade de propaga??o e forte amplitude. A Transformada de Karhunen-Lo?ve ? uma ?tima ferramenta para identifica??o de padr?es baseada nos autovalores e autovetores. Em conjunto com a Transformada de Karhunen-Lo?ve ser? utilizado a Decomposi??o em Valores Singulares, j? que a mesma ? uma ?tima t?cnica matem?tica para manipula??o dos dados

The ground source resources are becoming more and more popular and now the ground source heat pumps are frequently used for heating and cooling different types of buildings. This thesis aims at giving a contribution in the development of the thermal modelling of borehole heat storage systems. Furthermore, its objective is to investigate the possibility of implementing of a GSHP (ground source heat pump) with vertical boreholes, in order to deliver the heating and cooling demand for a passive house and to emphasize some certain advantages of this equipment even in the case of a small building (e.g. residential house). A case study is presented to a suitable modelling tool for the estimation of the thermal behaviour of these systems GSHP by combining the outcome from different modelling programs. In order to do that, a very efficient residential solar house (EFden House – a passive residential single-family house, which was projected and built in Bucharest with academic purposes) is being analysed. The numerical results are produced using the software DesignBuilder, EED (Earth Energy Designer) and a sizing method for the length of the boreholes (ASHRAE method). The idea of using 2 different modelling programs and another sizing method for the borehole heat exchanger design (ASHRAE method) is to make sure that all the calculations and results are valid and reliable when analysing such a system theoretically (in the first phases of implementing a project), before performing a geotechnical study or a thermal response test in order to assess the feasibility of such a project beforehand. The results highlight that the length of the borehole, which is the main design parameter and also a good index in estimating the cost of the system, is directly influenced by the other fundamental variables like thermal conductivity of the grout, of the soil and the heat carrier fluid. Also, some correlations between these parameters and the COP (coefficient of performance) of the system were made. The idea of sizing the length of boreholes using two different methods shows the reliability of the modelling tool. The results showed a difference of only 2.5%.  Moreover, the length of borehole is very important as it was calculated that can trigger a difference in electricity consumption of the GSHP up to 28%. It also showed the fact that the design of the whole system can be done beforehand just using modelling tools, without performing tests in-situ. The method aims at being considered as an efficient tool to estimate the length of the borehole of a GSHP system using several modelling tools. / <p>The presentation was made via Skype due to the programme being online based</p>

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-10-17T18:47:03Z No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-10-18T16:18:59Z (GMT) No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-18T16:18:59Z (GMT). No. of bitstreams: 3 Dissertação - Sara Brandão e Silva - 2016 - Parte 01.pdf: 12396227 bytes, checksum: 53cc99a947a01ed352cf6cbd21751a01 (MD5) Dissertação - Sara Brandão e Silva - 2016 - Parte 02.pdf: 10222149 bytes, checksum: 976fb375235891b3c9f19b810c83b325 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-01-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Topology optimization provides design solutions to several engineering applications and density methods are the most popular approach in this field. However, when it comes to building design, the dimension of the extended domain related to the high of the building provides material concentration at the basis of the building. On the other side, the ground structure method provides desirable grid solutions using a highly connected truss in an approach close to size optimization techniques. This work presents a prospective study about the application of ground structure method to obtain bracing systems for buildings comparing with the known solutions obtained by density methods. Desirable manufacturing constraints such as patterns repetition and symmetry are considered. Multiple loading functions are Simulations are developed in two-dimensional building configurations to validate the method and show the structural comportment. Three dimensional examples are developed to show possibility of interesting solutions obtained with the ground structure method. / A otimização de topologia fornece soluções para muitas aplicações da engenharia e os métodos baseados na densidade são as abordagens mais populares neste campo. No entanto, quando se trata da concepção de edifícios a dimensão do domínio estendido em relação à altura dos edifícios propicia a concentração de matéria na base do edifício. Por outro lado, o método da ground structure fornece soluções desejáveis usando uma treliça altamente conectada em uma abordagem próxima as técnicas de otimização de dimensões. Este trabalho apresenta um estudo sobrea a aplicação do método da ground structure para obtenção do projeto conceitual dos sistemas de contraventamento dos edifícios comparando com o conhecido método baseado na densidade. Para isso leva-se em consideração características de manufatura como simetria e repetição de padrão, além das considerações de múltiplos carregamentos. Simulações em 2D são apresentadas para validação do método e observação do comportamento estrutural. Exemplos em 3D com arquiteturas mais ousadas são desenvolvidos para mostrar as possiblidades arquitetônicas que as soluções obtidas pela ground structure propicia.

Na primeira parte do trabalho estudamos a equação de Schrödinger logarítmica com um delta potencial; $V(x)=-\\gamma \\,\\delta(x)$, onde $\\delta$ é a distribuição de Dirac na origem e o parâmetro real $\\gamma$ descreve a intensidade do potencial. Estabelecemos a existência e unicidade das soluções do problema de Cauchy associado em um espaço de funções adequado. No caso do potencial atrativo ($\\gamma>0$), calculamos de forma explícita o seu único ground state e mostramos a sua estabilidade orbital.\\\\ A segunda parte trata detalhadamente da equação de Schrödinger logarítmica com um delta derivada potencial; $V(x)=-\\gamma\\, \\delta^{\\prime}(x)$. A boa colocação global para o problema de Cauchy é verificada em um espaço de funções adequado. No caso do potencial atrativo ($\\gamma>0$), o conjunto dos ground states é completamente determinado. Mais precisamente: se $0<\\gamma\\leq2$, então há um único ground state e é uma função ímpar; se $\\gamma>2$, então existem dois ground states não-simétricos. Em adição, provamos que cada ground state é orbitalmente estável através de uma abordagem variacional. Finalmente, usando a teoria de extensão de operadores simétricos, também mostramos um resultado de instabilidade para $\\gamma>2$. / The first part of this thesis deals with the logarithmic Schrödinger equation with a delta potential; $V(x)=-\\gamma \\,\\delta(x)$, where $\\delta$ is the Dirac distribution at the origin and the real parameter $\\gamma$ is interpreted as the strength of the potential. We establish the existence and uniqueness of the solutions of the associated Cauchy problem in a suitable functional framework. In the attractive potential case ($\\gamma>0$), we explicitly compute the unique ground state and we show their orbital stability .\\\\ The second part deals with the case of the logarithmic Schrödinger equation with a delta prime potential; $V(x)=-\\gamma\\, \\delta^{\\prime}(x)$. Global well-posedness is verified for the Cauchy problem in a suitable functional space. In the attractive potential case ($\\gamma>0$), the set of the ground state is completely determined. More precisely: if $0<\\gamma\\leq2$, then there is a single ground state and it is an odd function; if $\\gamma>2$, then there exist two non-symmetric ground states. Moreover, we show that every ground state is orbitally stable via a variational approach. Finally, by applying the theory of extensions of symetric operators, we also prove a result of instability for $\\gamma>2$.

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