Unified approach to transformations of Painleve equations

Ankara : Department of Mathematics and Institute of Engineering and Sciences, Bilkent Univ., 1993.Thesis (Master's) -- Bilkent University, 1993.Includes bibliographical references leaves 36-37In this thesis, we iind the explicit form of some transformations associated with the second, third, fourth and fifth Painleve equations. These transformations are obtained by using the Schlesinger transformations associated with the linear system of equations of Painleve eciuations.The application of such transformations enables us to generate the new solutions of the given Painleve equation with different values of parameters, from the known solutions.Chahardehi, Ali Reza ModaressiM.S

Large Motion Assessment in Soils Under Dynamic Loading

This paper presents the mathematical formulation of the nonlinear multiphase dynamic model meant for porous media, obtained by applying the finite transformation assumption. This assumption is appropriate when large motions take place either during mass wasting processes, such as large slumps and earthflows, or during earthquake events when site liquefaction occurs and results for instance in large irrecoverable settlements or lateral spreads. The weak formulation and numerical implementation of the dynamic model uses the mesh-free h-p clouds method, which is based on the more general Partition of Unity Method. The mesh-free numerical methods seem indeed to be more appropriate for large transformation problems, where geometry may change in an important manner during simulation, as usual mesh constraints no longer exist. The numerical simulations of observed liquefaction-induced lateral spreads, performed with the proposed model are not presented in this paper

Global Methodology for Soil Behavior Identification and its Application to the Study of Site Effects

Though it is now admitted that non-linear modeling of soil behavior is necessary to represent some important aspects of the soil response under strong ground motion (for example, irreversible settlements and pore-pressure build-up), the elastoplastic models are not yet used in the everyday design processes. One of the obstacles is the difficulty to identify the models’ parameters. A methodology to identify the soil mechanical parameters is presented and applied to an elastoplastic model. The strategy is based on the use of minimum physical and easily measurable parameters. The key parameter necessary for characterizing the clay is its Liquidity Limit, while for the sand, the grain size distribution plays an important role. Once the methodology presented and validated comparing the response of the model’s response with the available data from the literature, the methodology is used to study the seismic response of the Mexico site

Mitigation of liquefaction seismic risk by preloading

Hazard

Critical Race Theory: An Empirical Investigation of its Benefits

Within the last decade, discussions regarding the implementation of critical race theory in education have gained significant controversy among educators and politicians. Although empirical research on critical race theory is limited, conservative states continue to place bans on the teaching of critical race theory (CRT) in K-12 schools (Carter, 2021). The purpose of this study was to build empirical research on CRT, specifically examining whether a course utilizing a critical race curriculum is effective in reducing negative stereotype beliefs and improving attitudes toward critical race theory. Nineteen undergraduate students who were enrolled in the course, IES 102: The Social Construct of Difference, at Chapman University, were selected to participate in this study. Within the first two weeks of the course, students were recruited to participate in an online pre-test that assessed their beliefs in stereotypes and attitudes toward the concept of critical race theory. In the last four weeks of the course, students were recruited back to complete a similar post-test, assessing their beliefs in stereotypes and attitudes toward the concept of critical race theory again. There was no significant difference between participants’ belief in stereotypes and attitude toward critical race theory before and after exposure to a critical race curriculum. However, students who identify as more liberal had a more positive attitude to CRT, and students who identify within a minority community had fewer beliefs in negative stereotypes. These results are significant as it demonstrates that beliefs in stereotypes and support for a critical race curriculum are dependent on identity. Based on the significant results of this study, educators and advocates should focus on debunking the myths of critical race theory and spreading awareness on its true values and curriculum, especially towards conservative groups. Additionally, educators should utilize activities to build empathy and perspective-taking skills towards “outgroups” to improve intergroup relations

Modeling and simulating semantic social overlay peer-to-peer systems.

The complexity of Peer-to-Peer (P2P) systems makes their analytical evaluation complicated. To conquer this problem, simulation studies are usually used to evaluate such systems. However, evolution of P2P systems, from simply a Gnutella-like network to advanced overlays, makes their comparison difficult in a similar condition. Using different inputs, outputs and datasets is the main cause of this problem. On the other hand, network simulators cannot be used for such systems because of high scalability and dynamicity of P2P systems. Most network simulators can simulate few nodes in high detail without considering dynamicity of systems. In this study, a generic model, parameters and datasets are presented and used to design a flow-based P2P simulator with the capability of implementing different P2P protocols to simplify the evaluation of P2P systems. Then, the behavior of a semantic social overlay P2P system is investigated and compared with two various types of overlays, namely random and interest-based systems to show the applicability of the simulator. Although three different types of overlays have been chosen, the generic model and selected parameters used in the proposed simulator provide a uniform environment to evaluate and compare different types of overlays in similar conditions

Numerical Modelling Approaches for the Analysis of Earthquake Triggered Landslides

Different numerical approaches for the analysis of earthquake triggered landslides are studied. Improved simplified models are developed and their performance for evaluating the response of natural slopes subjected to earthquakes is studied. Using more sophisticated numerical techniques the influence of several factors such as the hydro mechanical behavior assumptions, 1D vs. 2D geometry, and the input motion are assessed. 2D computations have shown that the kinematics of the slope motion is largely affected by the geometry of the slope. As far as the soil behavior is concerned, the results indicate that introduction of progressive yielding in the soil model provides larger displacement, progressive pore-pressure generation and more diffuse deformation. For the input motion, the number of peaks and their amplitudes have been identified as being the mains factors for irreversible displacements