Parametric Soil-Structure Modeling for Rapid Climatic Disaster Response

Title from PDF of title page, viewed on July 15, 2015Thesis advisor: ZhiQiang ChenVitaIncludes bibliographic references (pages 124-128)Thesis (M.S.)--School of Computing and Engineering. University of Missouri--Kansas City, 2014Global climate changes have seemly caused acerbating impacts on coastal environments in terms of severe meteorological hazards, such as hurricanes and their induced storm surges, flooding, and heavy precipitation. Recent disasters of these types, such as HurricaneSandy, have afflicted millions in coastal communities and resulted in billion dollars of losses. Given disasters at such scales, field-based reconnaissance has become ever demanding than before. In the context of structural and geotechnical damage inspection, it calls for efficient tools that can analyze coastal structures that take a system modeling approach. Such a system approach should consider structuresthat are subjected to a combination of extreme forces and changes of boundary conditions, which may include hydrodynamic wave effects, hydraulic buoyancy, debris impact, and foundation scour. The objective of this thesis to develop a rapid tool for assessing the vulnerability of coastal structures subjected to climatic impacts. Similar tools have been widely used in Structural and Earthquake Engineering for design and loss assessment, such as the use of a fixed oscillator model characterized by a single parameter of Tn (the natural period of the structure). The direct hazardous impacts considered in this thesis are extreme hydraulic forces and local foundation scouring that may ultimately cause failure of coastal structures (i.e. collapse). The criteria of success of this tool emphasize that it should be as simple as the oscillator model in Earthquake Engineering and is parametric in terms of a few key (intrinsic) parameters to model the nonlinear behavior of a structure subjected to hydraulic storm surges and foundations scour. To precede, two research components are conducted. The first is a hypothesis-driven physical modeling experiment, in which a flume-based modeling is conducted to prove that storm surges can attack a structure by simultaneous surging and scouring. In the hydraulic flume, a generic foundation-structure system is placed and is subjected to forced vibration for probing the dynamic properties of the structure model. Test result successfully revealed the formation of foundation scour, the failure of structure, and the progressively modified dynamic characteristics of the soil-structure system. The second, based on the above flume-based evidence, is to computationally model such the failure of building systems in a reduced order subjected to the combined hazards of storm surges and foundation scour. In this thesis, Ibuild afinite-element (FE) based model using Abaqus software. In this model, the structural system response has been resolved from prototype models to simplified dimensionless model consisting of a single degree of freedom (SDOF) oscillator founded on a square foundation. The footing is embedded in near-field soil modeled using inelastic soil under an undrained condition. The two primary intrinsic parameters identified in this thesis. The first is theratio of the vertical foundation load N in comparison with the ultimate vertical capacity Nu, expressed through the ratio χ = N/Nu. The second is defined as ao = ω H / vswhere ω is the circular frequency of the fixed base structure, H is the height of superstructure and vs is the shear wave velocity. Rocking response of the (SDOF) system on nonlinear soil is examined through the general-purpose finite element software Abaqus to perform the parametric analysis, and to establish the failure mechanism of the system. Lightly loaded oscillators tend to uplift from the supporting soil whereas heavily loaded oscillators tend to accumulate settlement and soil yielding is intense. The structural response corresponding to moment-rotation settlement under monotonic loading at the mass center, under loading has been designed to output. The Python-based Abaqus scripting interface is used to realize a client-based model input, which is an extension of the Python object-oriented programming language.Impact of climate on changes in civil infrastructure -- Literature review -- Physical modeling methodology and system identification -- Soil material modeling and verification -- Parametric soil-structure modeling using Abaqus CAE -- Conclusions and future work -- Appendix A. -- Appendix

LWPP and WPP are not uniformly gap-definable

AbstractResolving an issue open since Fenner, Fortnow, and Kurtz raised it in [S. Fenner, L. Fortnow, S. Kurtz, Gap-definable counting classes, J. Comput. System Sci. 48 (1) (1994) 116–148], we prove that LWPP is not uniformly gap-definable and that WPP is not uniformly gap-definable. We do so in the context of a broader investigation, via the polynomial degree bound technique, of the lowness, Turing hardness, and inclusion relationships of counting and other central complexity classes

Hemangiopericytoma of the spleen: Unusual presentation as multiple abscess

BACKGROUND: Hemangiopericytoma is a soft tissue vascular neoplasm arising from capillary pericytes and is found throughout the body in soft tissues and bone. It was first described in 1942. Primary vascular neoplasm of the spleen constitutes the majority of nonhaematolymphoid splenic tumors like haemangioma, lymphangioma, hemangioendothelioma, hemangiopericytoma etc. Splenic hemangiopericytoma is a rare tumor and probably first case was described in 1989. Uptill now only eight cases are reported in the English literature. CASE PRESENTATION: A-35-year old male presented with fever and dull aching pain in left hypochondriac region. Radiological evaluation showed presence of multiple abscesses in spleen. Investigations were done to rule out common causes of abscess in spleen. After failure of medical management, he was subjected to elective splenectomy. There were dense adhesions between the spleen and the adjacent structures and the diaphragm. The histopathology of the resected specimen showed hemangiopericytoma of spleen. CONCLUSION: The present case illustrate that the hemangiopericytoma of spleen can mimic as multiple abscess. Splenectomy is the treatment of choice

Pair-Interactions of Self-Propelled SiO2-Pt Janus Colloids

Driven by the necessity to achieve a thorough comprehension of the bottom-up fabrication process of functional materials, this experimental study investigates the pair-wise interactions or collisions between chemically active SiO2-Pt Janus Colloids. These collisions are categorized based on the Janus colloids' orientations before and after they make physical contact. In addition to the hydrodynamic interactions, the Janus colloids are also known to affect each other's chemical field, resulting in chemophoretic interactions, which depend on the reactive nature of the metal site. These interactions lead to a noticeable decrease in particle speed and changes in orientation, which depends on the duration of contact, yielding different collision types. Our findings reveal distinct configurations of contact during collisions, whose mechanisms and likelihood is found to be dependent primarily on the chemical interactions. Such estimates of collision and their characterization in dilute suspensions shall have key impact in determining the arrangement and time scales of dynamical structures and assemblies of denser suspensions, and potentially the functional materials of the future.Comment: 15 pages, 11 figures

Magneto Transport of high TCR (temperature coefficient of resistance) La2/3Ca1/3MnO3: Ag Polycrystalline Composites

We report the synthesis, (micro)structural, magneto-transport and magnetization of polycrystalline La2/3Ca1/3MnO3:Agx composites with x = 0.0, 0.1, 0.2, 0.3 and 0.4. The temperature coefficient of resistance (TCR) near ferromagnetic (FM) transition is increased significantly with addition of Ag. The FM transition temperature (TFM) is also increased slightly with Ag addition. Magneto-transport measurements revealed that magneto-resistance MR is found to be maximum near TFM. Further the increased MR of up to 60% is seen above 300 K for higher silver added samples in an applied field of 7 Tesla. Sharp TCR is seen near TFM with highest value of up to 15 % for Ag (0.4) sample, which is an order of magnitude higher than as for present pristine sample and best value yet reported for any polycrystalline LCMO compound. Increased TCR, TFM and significant above room temperature MR of La2/3Ca1/3MnO3:Agx composites is explained on the basis of improved grains size and connectivity with silver addition in the matrix. Better coupled FM domains and nearly conducting grain boundaries give rise to improved physical properties of the La2/3Ca1/3MnO3 manganites.Comment: 16 pages Text + Figs. ACCEPTED: Solid State Communications (Sept. 2006

Inter comparison of the magneto transport of La2/3Ca1/3MnO3: Ag/In polycrystalline composites

In this article, we report the synthesis, magneto transport features, and magnetization of polycrystalline La2/3Ca1/3MnO3:Agx/Inx composites with x = 0, 0.1, 0.2, 0.3 and 0.4. In case of Ag the temperature coefficient of resistance (TCR) near ferromagnetic (FM) transition enhances significantly with addition of Ag. The FM transition temperature (TFM) is also increased slightly with Ag doping. Magneto-transport measurements revealed that magneto-resistance (MR) is found to be maximum near TFM. Very sharp TCR is seen near TFM with highest value of up to 15 % for Ag (0.4) sample, which is an order of magnitude higher than as for pristine sample and is the best value yet reported for any polycrystalline LCMO compound. Increased TCR, TFM and significant above room temperature MR of La2/3Ca1/3MnO3:Agx composites is explained on the basis of improved grains size. Interestingly the La2/3Ca1/3MnO3:Inx composites behaved exactly in opposite way resulting in decreased TFM, and TCR compared to pristine LCMO compound. In fact the grains morphology of LCMO:Inx composites is seen inferior to pristine LCMO which is opposite to the LCMO:Agx case.Comment: 13 pages of TEXT+Fig

A Parameter Based Comparative Study of Deep Learning Algorithms for Stock Price Prediction

Stock exchanges are places where buyers and sellers meet to trade shares in public companies. Stock exchanges encourage investment. Companies can grow, expand, and generate jobs in the economy by raising cash. These investments play a crucial role in promoting trade, economic expansion, and prosperity. We compare the three well-known deep learning algorithms, LSTM, GRU, and CNN, in this work. Our goal is to provide a thorough study of each algorithm and identify the best strategy when taking into account elements like accuracy, memory utilization, interpretability, and more. To do this, we recommend the usage of hybrid models, which combine the advantages of the various methods while also evaluating the performance of each approach separately. Aim of research is to investigate model with the highest accuracy and the best outcomes with respect to stock price prediction