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Tola, Adrian Patricio. "Development of a Comprehensive Linear Response History Analysis Procedure for Seismic Load Analysis." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/36106.
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This thesis reviews the parameters required to perform linear response history analysis according to Chapter 16 of the American Standard ASCE 7-10. A careful analysis is presented about the selection of ground motions using real records and using artificial records generated such that their response spectrum matches with a defined target spectrum; three different techniques are studied for the generation of these artificial records. Also, this document revises the scaling of ground motion techniques in the American Standard ASCE-7 as well as in other seismic codes. It presents a detailed analysis of the variables influencing the scaling of ground motions, and it suggests a new scaling technique for linear response history analysis. The assumptions made establishing the flexibility of the diaphragms are also analyzed as well as dynamic methods to include accidental torsion when doing a linear response history analysis. Other modeling issues such as the orientation of the ground motion axis, scaling of element forces and displacements, orthogonal loading, solution techniques, P-Delta effects, modeling of the basement, and calculation of drifts are also studied in the context of linear response history analysis. The thesis concludes with suggested code language for linear response history analysis intended to be considered in future editions of the American Standard ASCE 7.Master of Science
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Aswegan, Kevin Paul. "Rational Procedure for Damage Based Serviceability Design of Steel Buildings Under Wind Loads and a Simple Linear Response History Procedure for Building Codes." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/51549.
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This thesis is divided into two topics: the development of a procedure for wind serviceability design of steel buildings and the development of a simple linear response history analysis for building codes.
In the United States the building codes are generally silent on the issue of serviceability. This has led to a wide variation in design practices related to service level wind loads. Chapter 2 of this thesis contains a literature review which discusses pertinent aspects of wind drift serviceability, including selecting the mean recurrence interval (MRI), mathematical modeling of the structure, and establishment of rational deformation limits. Chapter 3 contains a journal article submitted to Engineering Journal which describes the recommended procedure for damage based wind serviceability design of steel structures. The procedure uses a broad range of MRIs, bases damage measurement on shear strains, includes all sources of deformation in the model, and bases deformation limits on fragility curves.
Chapter 4 of this thesis contains a literature review which examines issues related to performing linear response history analysis. Chapter 5 contains a conference paper submitted to the Tenth U.S. National Conference on Earthquake Engineering which serves as a position paper promoting the inclusion of a linear response history analysis procedure in future editions of the NEHRP Recommended Seismic Provisions and ASCE 7. The procedure address the following issues: selection and scaling of ground motions, the use of spectral matched ground motions, design for dependent actions, and the scaling of responses with the response modification coefficient (R) and the deflection amplification factor (Cd).Master of Science
3
Hata, Misako. "Non linear tolerance analysis by response surface methodology." Ohio : Ohio University, 2001. http://www.ohiolink.edu/etd/view.cgi?ohiou1173897314.
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Javed, Khalid. "Non linear seismic response of asymmetric buildings." Thesis, University of East London, 1999. http://roar.uel.ac.uk/1260/.
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The study presented in this thesis is an attempt towards a better understanding of the coupled lateral-torsional response of buildings subject to seismic ground motion. Some of the problems identified in the past studies are thoroughly investigated and some new areas of study are explored. Some of these problems encountered in the literature include (a) the existence of several definitions of uncoupled torsional to lateral frequency ratio (b) an arbitrary selection of structural parameters in a parametric analysis resulting in a physically inadmissible structure and (c) the effect of nonlinearity. Because of the simplified models with either eccentricity in one direction or the ground motion applied in only one direction, the effects of a bi-directional loading have not been investigated in detail. These effects may include the relative differences in the amplitude or phase components of the individual accelerograms and their orientation with respect to the building. The phase properties of accelerograms are of particular interest and these have not received much attention in the past. Using analytical methods such as Chasle's[16] and Gerschgorin's[39] theorems, the equation of motion of a bi-eccentric system is derived and all of the existing problems regarding the definition of structural parameters and their bounds are studied in depth. To facilitate nonlinear parametric study, a paraboloid non-linear elastic stiffness model is proposed. Fourier spectral methods are used to study the frequency domain characteristics of the accelerogram pair. The difference in phase and amplitude of the component frequencies in each direction are studied for their effects on the response. For phase difference, cross-correlation function is used as a comparative statistical indicator. USA earthquake records obtained from US National Geophysical Data Centre are grouped into four soil types and the analysis is performed for each group in order to explore the soil-dependency of the aforementioned effects on the response. Computer programs are written in FORTRAN for both parametric and numerical model analyses. The latter can handle any number and orientation of columns with the assumed nonlinear stiffness properties. Newmark's and Runge-Kutta methods of numerical integration with adaptive step size control have been used to calculate parametric and the hysteretic responses of the system. The response to harmonic ground acceleration is used as a preliminary investigation into the response to actual accelerogram frequency components. The study has developed relationships for different definitions of the uncoupled torsional to lateral frequency ratio. Detailed derivation of the Equation of Motion has clarified the confusion that produced different definitions in the past studies. Graphical descriptions of the admissibility bounds on system parameters are produced. The variation in the response quantities is studied for a range of amplitude and phase contents of the applied ground acceleration. The difference in phase and amplitude in x and y ground accelerations have been found to affect the response quite significantly. More generally, the relationship of these differences to the torsional mode amplification has been observed. The effects of structural frequency and eccentricity parameters are also studied. Graphs showing the relationship between, the angle of incidence of the accelerogram with respect to the principal axis of the building, and the phase difference in the accelerogram pair, have been produced. The proposed analysis involving the bi-directional ground acceleration on a bi-eccentric system is an improvement on the current methods employed in design practice. Further work is, however, required before simplified design recommendations can be made and some proposals for future research are given at the end of this thesis.
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Kasinos, Stavros. "Seismic response analysis of linear and nonlinear secondary structures." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33728.
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Understanding the complex dynamics that underpin the response of structures in the occurrence of earthquakes is of paramount importance in ensuring community resilience. The operational continuity of structures is influenced by the performance of nonstructural components, also known as secondary structures. Inherent vulnerability characteristics, nonlinearities and uncertainties in their properties or in the excitation pose challenges that render their response determination as a non-straightforward task. This dissertation settles in the context of mathematical modelling and response quantification of seismically driven secondary systems. The case of bilinear hysteretic, rigid-plastic and free-standing rocking oscillators is first considered, as a representative class of secondary systems of distinct behaviour excited at a single point in the primary structure. The equations governing their full dynamic interaction with linear primary oscillators are derived with the purpose of assessing the appropriateness of simplified analysis methods where the secondary-primary feedback action is not accounted for. Analyses carried out in presence of pulse-type excitation have shown that the cascade approximation can be considered satisfactory for bilinear systems provided the secondary-primary mass ratio is adequately low and the system does not approach resonance. For the case of sliding and rocking systems, much lighter secondary systems need to be considered if the cascade analysis is to be adopted, with the validity of the approximation dictated by the selection of the input parameters. Based on the premise that decoupling is permitted, new analytical solutions are derived for the pulse driven nonlinear oscillators considered, conveniently expressing the seismic response as a function of the input parameters and the relative effects are quantified. An efficient numerical scheme for a general-type of excitation is also presented and is used in conjunction with an existing nonstationary stochastic far-field ground motion model to determine the seismic response spectra for the secondary oscillators at given site and earthquake characteristics. Prompted by the presence of uncertainty in the primary structure, and in line with the classical modal analysis, a novel approach for directly characterising uncertainty in the modal shapes, frequencies and damping ratios of the primary structure is proposed. A procedure is then presented for the identification of the model parameters and demonstrated with an application to linear steel frames with uncertain semi-rigid connections. It is shown that the proposed approach reduces the number of the uncertain input parameters and the size of the dynamic problem, and is thus particularly appealing for the stochastic assessment of existing structural systems, where partial modal information is available e.g. through operational modal analysis testing. Through a numerical example, the relative effect of stochasticity in a bi-directional seismic input is found to have a more prominent role on the nonlinear response of secondary oscillators when compared to the uncertainty in the primary structure. Further extending the analyses to the case of multi-attached linear secondary systems driven by deterministic seismic excitation, a convenient variant of the component-mode synthesis method is presented, whereby the primary-secondary dynamic interaction is accounted for through the modes of vibration of the two components. The problem of selecting the vibrational modes to be retained in analysis is then addressed for the case of secondary structures, which may possess numerous low frequency modes with negligible mass, and a modal correction method is adopted in view of the application for seismic analysis. The influence of various approaches to build the viscous damping matrix of the primary-secondary assembly is also investigated, and a novel technique based on modal damping superposition is proposed. Numerical applications are demonstrated through a piping secondary system multi-connected on a primary frame exhibiting various irregularities in plan and elevation, as well as a multi-connected flexible secondary system. Overall, this PhD thesis delivers new insights into the determination and understanding of the response of seismically driven secondary structures. The research is deemed to be of academic and professional engineering interest spanning several areas including seismic engineering, extreme events, structural health monitoring, risk mitigation and reliability analysis.
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Ashokkumar, C. R. "Eigenvalue/eigenvector perturbation for time response analysis of linear uncertain systems /." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487858417983696.
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Landschoot, Timothy P. "Suppression of the transient response in linear time-invariant systems /." Online version of thesis, 1994. http://hdl.handle.net/1850/11794.
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Bakir, Serhan. "Evaluation Of Seismic Response Modification Factors For Steel Frames By Non-linear Analysis." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607827/index.pdf.
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In this study steel framing systems are investigated with regards to their lateral load carrying capacity and in this context seismic response modification factors of individual systems are analyzed. Numerous load resisting layouts, such as different bracing systems and un-braced moment resisting frames with various bay and story configurations are designed and evaluated in a parametric fashion. Three types of beam to column connection conditions are incorporated in evaluation
process.
Frames, designed according to Turkish seismic code, are investigated by nonlinear static analysis with the guidance of previous studies and recent provisions of FEMA. Method of analysis, design and evaluation data are presented in detail.
Previous studies in literature, history and the theory of response modification phenomenon is presented.
Results are summarized, main weaknesses and ambiguities introduced to design by the use of &ldquoR&rdquo
factors are stated depending on the observed behavior.
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YU, XIAOHUA ANNIE. "TIME HISTORY ANALYSIS OF THE DYNAMIC RESPONSE OF HORIZONTAL LIFELINES." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060886371.
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Savage, Christopher Jon. "Implications of Dune Pattern Analysis for Titan's Surface History." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/3077.
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Analyzing dune parameters such as dune width and spacing can be useful in determining the reaction of dunes to changes in atmospheric and sedimentary conditions currently and in the recent geologic past. Dune parameters, dune width and spacing, were measured for linear dunes in regions across Saturn's moon Titan from images T21, 23, 28, 44 and 48 collected by Synthetic Aperture RADAR aboard the Cassini spacecraft in order to reconstruct the surface history of Titan. Dunes in the five study swaths are all linear in form, but lack superimposed or flanking dunes. They have a mean width of 1.3 km and mean crest spacing of 2.7 km, wider and farther apart on average than similar terrestrial dunes in the Namib and Agneitir Sand Seas though larger linear dunes exist on Earth. Because of the lack of superimposed and flanking dunes and their size, Titan's dunes are classified as very large simple linear dunes. The large size, spacing and uniform morphology are all indicators that Titan's dunes are very mature and long-lived features. The ratio of dune width to spacing for Titan's dunes is similar to that found in terrestrial dunes in that dune spacing tends to be twice dune width. In addition to being similar in size, this is further evidence that terrestrial dunes can be used as analogues for Titan's dunes and vice versa and that the essential dune-forming processes are the same on both bodies. Dune width and spacing decrease northward, which is attributed to, but not limited to, increased maturity of dune fields to the south or increased sediment stabilization to the north. Sediment stabilization may be caused by Titan's asymmetric seasons and a net transport of moisture from south to north. The majority of dunes have spacings consistent with an upper limit of 2 to 4 km established by the atmospheric boundary layer, further evidence they are mature. Dunes are more widely spaced in the south are evidence they have been growing toward a steady state for a longer period of time than those in the north. Titan's large linear dunes have long reconstitution times. This is in part due to the fact that winds sufficient for saltation are reached only near the Titan equinox every 14 Earth years. Based on rates for similar terrestrial dunes the reconstitution time for Titan's dune is 600,000 Earth years or more, and therefore substantial changes in dune form should not be observable over Cassini's lifetime. Cumulative probability plots of dune parameters measured at different locations across Titan indicate there is a single population of dunes on Titan. This suggests that, unlike analogous dunes in the Namib and Agneitir Sand Seas, dune-forming conditions that currently exist on Titan are either the only dune-friendly conditions in the moon's history, or the current conditions have been stable and active long enough to erase any evidence of past conditions.
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Jacobs, William. "Bayesian non-linear system identification and frequency response analysis with application to soft smart actuators." Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/13824/.
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Newly emerging classes of next generation soft-smart actuators are set to have a huge impact on the fields of robotics, orthotics and prosthetics due to their lightweight, high-strain and muscle-like properties. Like muscle, these actuators can be used in multiple roles, e.g. both as actuators and brakes, due their variable compliance. One important class of soft actuator is the dielectric elastomer actuator (DEA). However, DEAs are extremely difficult to control due to their non-linear and time varying dynamics. A crucial step in the advancement of this technology is the development of techniques for systems level modelling and analysis, which is the focus of this thesis. In the first part of the thesis, a set of DEAs are identified and analysed using standard methods from the field of system identification, obtaining non-linear autoregressive with exogenous input (NARX) models. These provide a benchmark against which later methods are evaluated. The key novelty in this part is the development of NARX models of DEAs for use in non-linear frequency-domain analysis. This result provides insight for the first time into how a set of similarly fabricated DEAs vary in different ways. A further aspect of DEA behaviour is their unexplained time varying behaviour. The system identification approach used to identify NARX models of DEAs is in a convenient form such that it can be easily extended to cater for this time varying behaviour. There are however very few available methods for the frequency domain analysis of time varying systems. A novel method for time varying frequency domain analysis of NARX systems is developed in this work and applied to the DEAs. The analysis procedure is used to provide insight on how the dynamic behaviour of DEAs change over time. In the second part of the thesis a novel approach to the joint structure detection and parameter estimation of NARX models is developed using a sparse Bayesian method. The Bayesian framework allows for the estimation of posterior distributions over model parameters, characterising the model uncertainty. Analytic solutions are found that describe model uncertainty in the frequency-domain as confidence bounds on both linear and higher order frequency response functions. The sparse Bayesian identification algorithm is applied to the DEA data sets and is used to give the first non-linear dynamic model of DEAs with uncertainty bounds plus the first description of DEA dynamics in the frequency-domain, again with uncertainty bounds.
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Tran, Tuan H. "Landing-Gear Impact Response: A Non-linear Finite Element Approach." UNF Digital Commons, 2019. https://digitalcommons.unf.edu/etd/896.
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The primary objective of this research is to formulate a methodology of assessing the maximum impact loading condition that will incur onto an aircraft’s landing gear system via Finite Element Analysis (FEA) and appropriately determining its corresponding structural and impact responses to minimize potential design failures during hard landing (abnormal impact) and shock absorption testing. Both static and dynamic loading condition were closely analyzed, compared, and derived through the Federal Aviation Administration’s (FAA) airworthiness regulations and empirical testing data.
In this research, a nonlinear transient dynamic analysis is developed and established via NASTRAN advanced nonlinear finite element model (FEM) to simulate the worst-case loading condition. Under the appropriate loading analysis, the eye-bar and contact patch region theory were then utilized to simulate the tire and nose wheel interface more accurately. The open geometry of the nose landing gear was also optimized to minimize the effect of stress concentration. The result of this research is conformed to the FAA’s regulations and bound to have an impact on the design and development of small and large aircraft’s landing gear for both near and distant future.
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Brand, Jan Adriaan. "A linear response surface analysis approach to evaluate QoS factors in wireless networks / Jan Adriaan Brand." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8654.
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With the growth of wireless networks and the increase in personal internet use for a wide
diversity of applications, the importance of the quality of service (QoS) delivered to clients
has become of great importance. In order to evaluate QoS, this study explores the
application of the linear response surface analysis (LRSA) technique as an evaluation tool
for QoS factors such as Throughput and Delay. An 802.11n prototype wireless network is
constructed in order to capture QoS data that is then used to construct LRSA models in
order to evaluate the QoS factors. The LRSA models are maximised and minimised while
constraining specific measured QoS factors and the subsequent results are analysed. Based
on this analysis, recommendations for the improvement of wireless networks are made as
well as the use of the LRSA technique to evaluate QoS within a wireless network.Thesis (MSc (Computer Science))--North-West University, Potchefstroom Campus, 2013
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Chaulagain, Hemchandra. "Assessment of response reduction factor of RC buildings in Kathmandu Valley using non-linear pushover analysis." Master's thesis, Purbanchal University, 2010. http://hdl.handle.net/10773/12681.
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Master of Engineering in EarthquakeThis study addresses the issue of response reduction factor which is used in modern codes to scale down the elastic response of the structure. The level of ductility and overstrength of RC buildings in Kathmandu valley are investigated. The ductility and overstrength factors are estimated by analyzing the buildings using non-linear pushover analysis for 12 engineered designed RC buildings of various characteristics representing a wide range of RC buildings in Kathmandu valley. Finally, the response reduction factor of RC building in Kathmandu valley is evaluated by using the relation of ductility and overstrength factor.
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Scarpato, Alessandro. "Linear and nonlinear analysis of the acoustic response of perforated plates traversed by a bias flow." Thesis, Châtenay-Malabry, Ecole centrale de Paris, 2014. http://www.theses.fr/2014ECAP0038/document.
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Les instabilités thermo-acoustiques causent des problèmes récurrents dans les chambres de combustion pour une large gamme d'applications industrielles, allant des chaudières domestiques aux turbines à gaz, en passant par les moteurs fusées. Ces phénomènes résultent d’un couplage résonant entre la dynamique de la combustion et les modes acoustiques du foyer, et peuvent donner lieu à de fortes vibrations, un vieillissement prématuré des composants de la chambre, voire des dommages structurels. Les mécanismes physiques mis en jeu sont complexes et difficiles à modéliser, ainsi les oscillations thermo-acoustiques ne sont pas facilement prévisibles au stade de la conception d’une chambre de combustion. Dans de nombreux foyers, des systèmes d’amortissement passifs sont installés pour augmenter la dissipation d’énergie acoustique et empêcher le développement de ces instabilités. Dans ce travail, des systèmes d’amortissement basés sur des plaques perforées couplées à une cavité résonante et traversées par un écoulement moyen sont analysés. Les principaux objectifs sont : (i) d’améliorer et de simplifier la conception de systèmes d’amortissement robustes en maximisant leurs propriétés d’absorption acoustique en régime linéaire, (ii) d’analyser l’effet de l’amplitude des ondes sonores incidentes sur la réponse acoustique des plaques perforées et (iii) de développer des modèles capables de reproduire cette réponse aux hautes amplitudes. Tout d’abord, deux régimes asymptotiques intéressants sont identifiés où le système fonctionne à faibles et forts nombres de Strouhal respectivement. Dans ces régimes la conception d’un système d’amortissement maximisant l’absorption acoustique est grandement simplifiée, puisque les calculs de la vitesse optimale de l’écoulement et de la taille de la cavité sont découplés. Il est démontré qu’à faible nombre de Strouhal le système se comporte comme un résonateur quart d’onde, et dispose d’une bande d’absorption très large. À fort nombre de Strouhal, le système fonctionne comme un résonateur de Helmholtz, comportant une cavité de taille plus réduite, mais une bande d’absorption beaucoup plus étroite que dans le régime précédent. Ces prévisions sont confirmées par des mesures réalisées dans les différents régimes identifiés sur un dispositif expérimental dédié. L’évolution des propriétés acoustiques d’une plaque perforée lorsque l’amplitude de forçage augmente est ensuite examinée par le biais de simulations directes. Il est montré que la transition du régime linéaire au régime non linéaire se produit lorsque l’amplitude de la vitesse acoustique dans l’orifice est comparable à la vitesse de l’écoulement moyen dans les trous. Pour des amplitudes élevées, une inversion périodique de l’écoulement est observée dans l’orifice. Des anneaux tourbillonnaires sont alternativement éjectés en amont et en aval de l’orifice à une vitesse de convection qui augmente avec l’amplitude de la perturbation acoustique. Ces mécanismes influencent profondément l’absorption acoustique des plaques perforées dans le régime non linéaire. Deux nouveaux modèles décrivant la réponse non linéaire de ces systèmes sont ensuite développés en exploitant la trajectoire des vortex (modèle VC), et une approche quasi-stationnaire (modèle IDF). Les prévisions de ces modèles sont confrontées à des mesures effectuées dans le tube à impédance et aux résultats de simulations directes. Les résultats obtenus au cours de ces travaux peuvent être utilisés pour guider la conception de systèmes d’absorption robustes, capables de fonctionner dans des environnements difficiles avec des niveaux sonores élevés, comme ceux rencontrés lors d’instabilités thermo-acoustiquesThermo-acoustic instabilities are of primary concern in combustion chambers for a wide range of industrial applications, from domestic boiler to gas turbines or rocket engines. They are the consequence of a resonant coupling between the flame dynamics and the acoustic modes of the combustor, and can result in strong vibrations, early aging of combustor components and structural damage. The physical mechanisms involved are complex and difficult to model, thus thermo-acoustic oscillations are not easily predictable at the design stage of a combustor. In many combustors, passive dampers are implemented to increase the acoustic energy dissipation of the system and to hinder detrimental flame-acoustics interactions. In the present work, passive damping systems based on perforated screens backed by a resonant cavity and traversed by a bias flow are investigated. The main objectives are: (i) to improve and simplify the design of these dampers by maximizing their acoustic absorption properties in the linear regime, (ii) to analyze the effect of the sound wave amplitude on the acoustic response of these systems and (iii) to develop models capable of capturing absorption at high oscillation amplitudes. First, two interesting asymptotic regimes are identified where the plate operates at low and high Strouhal numbers respectively. In these regimes the design of a damper maximizing absorption is greatly simplified, since the choice of the optimal bias flow velocity and back cavity size can be decoupled. It is shown that at low Strouhal numbers the damper behaves as a quarter-wave resonator, and features a wide absorption bandwidth. At high Strouhal numbers, the system operates as a Helmholtz resonator, featuring shorter optimal back cavity sizes but narrower absorption bandwidths. These predictions are compared to measurements in a dedicated experimental setup for the different operating regimes identified. The dependence of the acoustic properties of a perforated plate on the forcing amplitude is then examined by means of direct numerical simulations. It is shown that transition from linear to nonlinear regimes occurs when the acoustic velocity amplitude in the orifice is comparable to the mean bias flow velocity. At high amplitudes, periodic flow reversal is observed within the perforation, vortex rings are alternatively shed upstream and downstream of the hole and convected away at a velocity which is increasing with the forcing amplitude. These mechanisms greatly influence the acoustic absorption of the perforate in the nonlinear regime. Two novel models capturing this nonlinear response are then inferred based on an analysis of the vortex trajectory (VC model), and on a quasi-steady description of the flow (IDF model). Their predictions are finally compared to measurements conducted in an impedance tube, and to results from numerical simulations. The results obtained in this work can be used to ease the design of robust dampers capable of operating in harsh environments with high sound levels, such as those found during self-sustained thermo-acoustic instabilities
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NZULU, GABRIEL. "Optical analysis of doped PbTe samples using UV- VIS and IR ellipsometry." Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-10435.
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Lead-tin telluride alloy, Pb1-xSnxTe, is a narrow band gap group IV–VI semiconductor with NaCl-like crystalline structure. This material has interesting electronic properties, which makes it suitable for designing infrared photo detectors, diode lasers, and thermo-photovoltaic energy converters. In this project, we used spectroscopic ellipsometry in the spectral range of 0.74–6.5 eV to probe the linear optical response of Pb1-xSnxTe alloys in terms of the complex dielectric function. A strong optical response in the range of 0.7-2.0 eV arising from optical absorption was found. We studied eleven different samples of Pb1-xSnxTe of p-type origin with x values in the range (0 ≤ x ≤ 1). They were prepared by means of molecular beam epitaxy (MBE) on BaF2 substrates with 15mm2 area.
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Hudson, Donna. "Analysis of the effects of treatments on non-linear models for nitrogen response curves, with implications for design." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360011.
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Morgan, Andrew Scott. "Seismic Response of Stiffening Elastic Systems." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3491.
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Traditional seismic load resisting systems in buildings are designed to undergo inelastic deformations in order to dissipate energy, resulting in residual displacements. This work explores an approach to eliminate these residual displacements. The systems investigated have low initial stiffness which increases at a predefined displacement, and are therefore called stiffening elastic systems. This thesis begins with an examination of single-degree-of-freedom stiffening elastic systems. A case study is presented which suggests that the benefits from stiffening elastic behavior may be limited to systems which would have long periods if designed traditionally. A thorough parameter study is also presented which indicates the benefit of stiffening elastic behavior for SDOF systems with periods greater than four seconds. A final case study is presented that compares the response of a twelve-story stiffening elastic system to a ductile system and an elastic system. The stiffening elastic system was able to eliminate the residual displacements inherent in a ductile system while lowering the base shear experienced by the elastic system, but is not clearly better than the ductile system because the base shear force was much higher.
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Leung, Colin. "SENSITIVITY OF SEISMIC RESPONSE OF A 12 STORY REINFORCED CONCRETE BUILDING TO VARYING MATERIAL PROPERTIES." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/681.
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The main objective of this investigation is to examine how various material properties, governed by code specification, affect the seismic response of a twelve- story reinforced concrete building. This study incorporates the pushover and response history analysis to examine how varying steel yield strength (Fy), 28 day nominal compressive concrete strength (f’c), modes, and ground motions may affect the base shear capacity and displacements of a reinforced concrete structure.
Different steel and concrete strengths were found to have minimal impact on the initial stiffness of the structure. However, during the post-yielding phase, higher steel and concrete compressive strengths resulted in larger base shear capacities of up to 22%. The base shear capacity geometric median increased as f’c or Fy increased, and the base shear capacity dispersion measure decreased as f’c or Fy increased. Higher mode results were neglected in this study due to non-convergent pushover analyses results.
According to the response history analysis, larger yield and concrete compressive strengths result in lower roof displacement. The difference in roof displacement was less than 12% throughout. This displays the robustness of both analysis methods because material properties have insignificant impact on seismic response. Therefore, acceptable yield and compressive strengths governed by seismic code will result in acceptable building performance.
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Kniola, David J. "Constructing an Estimate of Academic Capitalism and Explaining Faculty Differences through Multilevel Analysis." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/29484.
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Two broad influences have converged to shape a new environment in which universities must now compete and operate. Shrinking financial resources and a global economy have arguably compelled universities to adapt. The concept of academic capitalism helps explain the new realities and places universities in the context of a global, knowledge-based economy (Slaughter & Leslie, 1997). Prior to this theory, the role of universities in the knowledge economy was largely undocumented. Academic capitalism is a measurable concept defined by the mechanisms and behaviors of universities that seek to generate new sources of revenue and are best revealed through faculty work. This study was designed to create empirical evidence of academic capitalism through the behaviors of faculty members at research universities. Using a large-scale, national database, the researcher created a new measureâ an estimate of academic capitalismâ at the individual faculty member level and then used multi-level analysis to explain variation among these individual faculty members. This study will increase our understanding of the changing nature of faculty work, will lead to future studies on academic capitalism that involve longitudinal analysis and important sub-populations, and will likely influence institutional and public policy.Ph. D.
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Lazar, Ann A. "Determining when time response curves differ in the presence of censorship /." Connect to abstract via ProQuest. Full text is not available online, 2008.
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Dittrich, Regina, Brian Francis, Reinhold Hatzinger, and Walter Katzenbeisser. "A Paired Comparison Approach for the Analysis of Sets of Likert Scale Responses." Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 2005. http://epub.wu.ac.at/654/1/document.pdf.
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This paper provides an alternative methodology for the analysis of a set of Likert responses measured on a common attitudinal scale when the primary focus of interest is on the relative importance of items in the set. The method makes fewer assumptions about the distribution of the responses than the more usual approaches such as comparisons of means, MANOVA or ordinal data methods. The approach transforms the Likert responses into paired comparison responses between the items. The complete multivariate pattern of responses thus produced can be analysed by an appropriately reformulated paired comparison model. The dependency structure between item responses can also be modelled flexibly. The advantage of this approach is that sets of Likert responses can be analysed simultaneously within the Generalized Linear Model framework, providing standard likelihood based inference for model selection. This method is applied to a recent international survey on the importance of environmental problems. (author's abstract)Series: Research Report Series / Department of Statistics and Mathematics
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Lombardo, Rafael Vasquez. "Analysis of rheological response of high molecular weight cyclic polymer melts to percolation caused by trace contamination from linear chains." Tallahassee, Fla. : Florida State University, 2010. http://purl.fcla.edu/fsu/lib/digcoll/undergraduate/honors-theses/2181922.
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Thesis (Honors paper)--Florida State University, 2010.Advisor: Dr. Sachin Shanbhag, Florida State University, College of Engineering, Dept. of Chemical & Biomedical Engineering. Includes bibliographical references.
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Gunay, Mehmet Selim. "An Equivalent Linearization Procedure For Seismic Response Prediction Of Mdof Systems." Phd thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609447/index.pdf.
Full textAbstract:
Nonlinear response history analysis is accepted as the most accurate analytical tool for seismic response determination. However, accurate estimation of displacement responses using conceptually simple, approximate analysis procedures is preferable, since there are shortcomings in the application of nonlinear response history analysis resulting from its complexity.
An equivalent linearization procedure, which utilizes the familiar response spectrum analysis as the analysis tool and benefits from the capacity principles, is developed in this thesis study as an approximate method for predicting the inelastic seismic displacement response of MDOF systems under earthquake excitations. The procedure mainly consists of the construction of an equivalent linear system by reducing the stiffness of structural members which are expected to respond in the inelastic range. Different from similar studies in literature, equivalent damping is not explicitly employed in this study. Instead, predetermined spectral displacement demands are utilized in each mode of the equivalent linear system for the determination of global displacement demands.
Response predictions of the equivalent linearization procedure are comparatively evaluated by using the benchmark nonlinear response history analysis results and other approximate methods including conventional pushover analysis and modal pushover analysis (MPA). It is observed that the proposed procedure results in similar accuracy with approximate methods which employ nonlinear analysis. Considering the conceptual simplicity of the procedure and the conventional analysis tools used in its application, presented equivalent linearization procedure can be suggested as a practically applicable method for the prediction of inelastic seismic displacement response parameters with sufficient accuracy.
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Parsa, Amanullah. "EFFECT OF BUILDING ORIENTATION ON STRUCTURAL RESPONSE OF REINFORCED CONCRETE MOMENT RESISTING FRAME STRUCTURES." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/theses/2698.
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In time history analysis of structures, the geometric mean of two orthogonal horizontal components of ground motion in the as-recorded direction of sensors, have been used as measure of ground motion intensity prior to the 2009 NEHRP provision. The 2009 NEHRP Provisions and accordingly the seismic design provisions of the ASCE/SEI 7-10, modified the definition of ground motion intensity measure from geometric mean to the maximum direction ground motion, corresponding to the direction that results in peak response of the oscillator. Maximum direction response spectra are assumed to envelope the range of maximum possible responses over all nonredundant rotation angles. Two assumptions are made in the use maximum ground motion as the intensity measure: (1) the structure’s strength and stiffness properties are identical in all directions and (2) azimuth of the maximum spectral acceleration coincides with the one of the principal axes of the structure. The implications of these assumptions are examined in this study, using 3D computer models of multi-story structures having symmetric and asymmetric layouts and elastic vibration period of 0.2 second and 1.0 second subjected to a set of 25 ground-motion pairs recorded at a distance of more than 20 km from the fault. The influence of the ground-motion rotation angle on structural response (here lateral displacement and story drift) is examined to form benchmarks for evaluating the use of the maximum direction (MD) ground motions. The results of this study suggest that while MD ground motions do not always result in largest structural response, they tend to produce larger response than the as-recorded ground motions. On the other hand, more research on non-linear seismic time history analysis is recommended, especially for asymmetric layout plan buildings.
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Sannestam, Anton. "Horror, History and You : A Reader-Response Analysis of the Function of History in Two Works of H.P. Lovecraft and Its Relevance for an EFL Classroom." Thesis, Linnéuniversitetet, Institutionen för språk (SPR), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76757.
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In this essay, reader-response theory is used to explore the application of history in "The Rats in the Walls" and "At the Mountains of Madness" by H.P. Lovecraft.Utilizing the concepts of the informed reader and temporal reading, this essay concludes that Lovecraft used history in two distinct ways. Firstly, history is used as a means to build immersion, ambience, and explore the individual's place in history by drawing upon English cultural layers. Secondly, it functions to reflect on human history in relation to human existence and geological history by turning the history of Earth into the history of an alien species. Furthermore, this essay concludes that Lovecraft and history could be valuble assets to an EFL classroom by relating the findings to theory on reader-response in education. Firstly, it enables students to reflect on social issues in the past and the present by looking at Lovecraft's historical settings, his antiquated prose and the casual racism he exhibits in his texts. Secondly, Lovecraft's apparent obsession with his historical identity and ancestry provides an opening for the students to contemplate their own sense of identity as it relates to culture and history. The underlying idea being that the best way to reveal Lovecraft's use of history is to consider what the individual reader brings to the reading experience.
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Naga, Pradeep. "Analyzing the Effect of Moving Resonance on Seismic Response of Structures using Wavelet Transforms." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/34646.
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Nonlinear structures, when subjected to multiple ground motion records that are scaled to consistent ground motion intensity show significant variation in their response. This effect of ground motion randomness on the variation of structural response is defined as Record-to-Record (RTR) Variability. Ground motion characteristics that contribute to this variability in response includes the variation of signal composition (frequency content) with time (spectral nonstationarity).The phenomenon of moving resonance which occurs when the frequency content of the ground motion shifts in a similar manner as the natural frequencies of the structural response, is likely a contributor to variability. This brings the need to further understand the sources of variability due to moving resonance.
The present study was carried out to develop a method to analyze the time-frequency content of a ground motion to assess the occurrence of moving resonance and to quantify its potential in effecting the structural systems. Bilinear elastic and elastoplastic hysteretic behavior was considered. Detailed analysis is done to quantify the effect of moving resonance on structural systems due to 22 far field ground motion records.
The wavelet coefficient plots gave very good detail of the characteristics of the ground motions that were not clear from the acceleration time histories and response spectra plots. Instances of moving resonance were found out to be significant. Amplification due to moving resonance was found to be quite large. One instance studied in detail (accelerogram of Northridge earthquake at Beverly Hills) had peak displacement amplified by 6 times compared to the amount of peak displacement expected if the system did not exhibit moving resonance. Based on the analyses results, the characteristics of the ground motion records that donâ t cause significant moving resonance effect on structural systems were observed. Similarly, the characteristics of the ground motions that do cause moving resonance effect on structural systems were examined.Master of Science
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Jakel, Roland. "Linear Dynamic System Analyses with Creo Simulate – Theory & Application Examples, Capabilities, Limitations –." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-225992.
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1. Einführung in die Theorie dynamischer Analysen mit Creo Simulate 2. Modalanalysen (Standard und mit Vorspannung) 3. Dynamische Analysen einschließlich Klassifizierung der Analysen; einige einfache Beispiele für eigene Studien (eine Welle unter Unwuchtanregung und ein Ein-Massen-Schwinger) sowie etliche Beispiele größerer dynamischer Systemmodelle aus unterschiedlichsten Anwendungsbereichen 4. Feedback an den Softwareentwickler PTC (Verbesserungsvorschläge und Softwarefehler) 5. Referenzen1. Introduction to dynamic analysis theory in Creo Simulate 2. Modal analysis (standard and with prestress) 3. Dynamic analysis, including analysis classification, some simple examples for own self-studies (shaft under unbalance excitation and a one-mass-oscillator) and several real-world examples of bigger dynamic systems 4. Feedback to the software developer PTC (enhancement requests and code issues) 5. References
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Erdural, Serkan. "A Method For Robust Design Of Products Or Processes With Categorical Response." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12608015/index.pdf.
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In industrial processes decreasing variation is very important while achieving the targets. For manufacturers, finding out optimal settings of product and process parameters that are capable of producing desired results under great conditions is crucial. In most cases, the quality response is measured on a continuous scale. However, in some cases, the desired quality response may be qualitative (categorical). There are many effective methods to design robust products/process through industrial experimentation when the response variable is continuous. But methods proposed so far in the literature for robust design with categorical response variables have various limitations.
This study offers a simple and effective method for the analysis of categorical response data for robust product or process design. This method handles both location and dispersion effects to explore robust settings in an effective way. The method is illustrated on two cases: A foam molding process design and an iron-casting process design.
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Persi, Erez. "Contrast and tuning response properties of neurons in the visual cortex : modeling and data analysis." Paris 6, 2008. http://www.theses.fr/2008PA066216.
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We have combined a theoretical and experimental approach to study the biophysical substrates for the coding of orientation and contrast in the activity of V1 neurons. We first explore theoretically how the emerging activity in V1 depends on the input properties, single neuron input-output transfer-function properties and the connectivity pattern within V1. We explain the conditions on the different input sources in a hypercolumn model, that allow for both contrast-invariant orientation tuning width and sigmoid contrast response functions (CRF). We emphasize the role of the systems' components and structure features and their relative contribution to the activity in V1. More specifically, we show that the nonlinearity in the input-output transfer function manifested by a power-law regime leads to the sharpening of both orientation tuning width and the CRF in V1 compared with its inputs. Saturation in the CRF is a result of sufficient cortical inhibition at high contrasts, which is easily achieved with power-law transfer functions. Then, we analyze experimental data of both in-vitro and in-vivo measurements, and show that the models' key assumptions are consistent with neuronal behavior. A central focus of our study is to explain the diversity in the CRFs parameters. We show that the model can account for this diversity with heterogeneity either in single neuron properties or in LGN input properties. A comparison with experimental data indicates an equal contribution of the two heterogeneity types. The theory presented here can be further developed and extended to several visual areas in order to investigate other mechanisms of visual processingAfin d’étudier les bases du codage de l’orientation et du contraste par les neurones du cortex visuel primaire (V1), nous avons utilisé une approche à la fois théorique et expérimentale. Nous analysons dans un premier temps et de façon théorique, comment l’activité émergente dans V1 dépend des propriétés d’entrée des neurones corticaux, de leur fonction de transfert « entrée-sortie » et des différents patrons de connectivité à l’intérieur de cette même structure. Nous nous penchons ensuite sur les différentes sources d’entrées d’un modèle d’hyper-colonne, en caractérisant les conditions qui permettent à la fois une sélectivité à l’orientation indépendante du contraste et une fonction de réponse au contraste (CRF) sigmoïde. De plus, nous soulignons le rôle des relations entre les propriétés intrinsèques des neurones et les propriétés du réseau. Plus précisément, nous montrons que les non-linéarités dans la fonction de transfert « entrée-sortie », caractérisées par une loi de puissance, entraînent l’étrécissement à la fois de la courbe de sélectivité à l’orientation et de la CRF dans V1. La saturation de la CRF résulte, elle, d’une inhibition corticale à fort contraste, ce qui est aisément réalisé avec des fonctions de transfert basées sur des lois de puissance. Dans un deuxième temps, nous analysons des données expérimentales provenant à la fois d’enregistrements in vitro et in vivo et montrons que les hypothèses clés de notre modèle sont en accord avec les comportements neuronaux. Un point central de notre étude est d’expliquer la diversité des paramètres de la CRF. Nous montrons que le modèle justifie cette diversité par l’hétérogénéité des propriétés du neurone lui-même ou de ses afférences thalamiques. De plus, les données expérimentales indiquent qu’il y a une contribution à part égale des deux types d’hétérogénéités. Les principes présentés ici sont valables pour d’autres aires visuelles et peuvent être appliqué d’autres mécanismes du traitement de l’information visuelle
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Arslan, Hakan. "A Numerical Study On Response Factors For Steel Wall-frame Systems." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610811/index.pdf.
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A numerical study has been undertaken to evaluate the response of dual systems which consist of steel plate shear walls and moment resisting frames. The primary objective of the study was to investigate the influence of elastic base shear distribution between the wall and the frame on the global system response. A total of 10 walls and 30 wall-frame systems, ranging from 3 to 15 stories, were selected for numerical assessment. These systems represent cases in which the elastic base shear resisted by the frame has a share of 10%, 25%, or 50% of the total base shear resisted by the dual system. The numerical study consisted of 1600 time history analyses employing three-dimensional finite elements. All 40 structures were separately analyzed for elastic and inelastic response by subjecting to the selected suite of earthquake records. Interstory drifts, top story drift, base shears resisted by the wall and the frame were collected during each analysis. Based on the analysis results, important response quantities such as the response modification, the overstrength, the displacement amplification and ductility reduction factors are evaluated herein. Results are presented in terms of several measures such as the interstory drift ratio
and the top story drift ratio. A discussion related to the influence of load share on the response factors is given.
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Ueckert, Sebastian. "Novel Pharmacometric Methods for Design and Analysis of Disease Progression Studies." Doctoral thesis, Uppsala universitet, Institutionen för farmaceutisk biovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-216537.
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With societies aging all around the world, the global burden of degenerative diseases is expected to increase exponentially. From the perspective drug development, degenerative diseases represent an especially challenging class. Clinical trials, in this context often termed disease progression studies, are long, costly, require many individuals, and have low success rates. Therefore, it is crucial to use informative study designs and to analyze efficiently the obtained trial data. The development of novel approaches intended towards facilitating both the design and the analysis of disease progression studies was the aim of this thesis. This aim was pursued in three stages (i) the characterization and extension of pharmacometric software, (ii) the development of new methodology around statistical power, and (iii) the demonstration of application benefits. The optimal design software PopED was extended to simplify the application of optimal design methodology when planning a disease progression study. The performance of non-linear mixed effect estimation algorithms for trial data analysis was evaluated in terms of bias, precision, robustness with respect to initial estimates, and runtime. A novel statistic allowing for explicit optimization of study design for statistical power was derived and found to perform superior to existing methods. Monte-Carlo power studies were accelerated through application of parametric power estimation, delivering full power versus sample size curves from a few hundred Monte-Carlo samples. Optimal design and an explicit optimization for statistical power were applied to the planning of a study in Alzheimer's disease, resulting in a 30% smaller study size when targeting 80% power. The analysis of ADAS-cog score data was improved through application of item response theory, yielding a more exact description of the assessment score, an increased statistical power and an enhanced insight in the assessment properties. In conclusion, this thesis presents novel pharmacometric methods that can help addressing the challenges of designing and planning disease progression studies.
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Teklemariam, Daniel Mekonnen, and Bennie Hamunzala. "Design of Thick Concrete Beams : Using Non-Linear FEM." Thesis, KTH, Bro- och stålbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189141.
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The experimental studies performed on the behaviour of very thick concrete beams subjected to static loads have revealed that the shear mechanisms play an important role in the overall response and failure behaviour. The aim of this thesis is to recommend suitable design methods for thick concrete beams subjected to off-centre static concentrated load according Eurocode 2 by using non-linear finite element analysis (NLFEA). To achieve this task, Abaqus/Explicit has been used by employing constitutive material models to capture the material non-linearity and stiffness degradation of concrete. Concrete damaged plasticity model and perfect plasticity model has been used for concrete and steel respectively. Three dilation angles (30º, 38º and 45º) and fracture energy from FIB 1990 (76 N/m) and FIB 2010 (142 N/m) has been used to investigate their influence on the finite element model. The dilation angle of 38º and FIB 2010 fracture energy was adopted as the suitable choice that reasonably matched with the experimental results. In verifying and calibrating the finite element model, the experimental results of the thick reinforced concrete beam conducted by the American Concrete Institute have been used. Three design approaches in the ultimate and serviceability limit state according to Eurocode 2 recommendations have been used namely; the beam method, strut and tie method and shell element method. Using the reinforcement detailing of the hand calculations of beam method and strut and tie method and linear finite element analysis of shell element method, non-linear finite element models have been pre-processed and analysed in Abaqus/Explicit. During the post-processing, the results have been interpreted and compared between the three design methods. The results under consideration are hand-calculated load at 0.3 mm crack width, FE-load at 0.3 mm crack width, amount of reinforcement and FE-failure load. The comparison of the results between the three design approaches (beam method, strut and tie method and shell element method) indicates that strut and tie method is better design approach, because it is relatively economic with regards to the quantity of reinforcement bars, has the higher load capacity and has a higher load at crack width of 0.3 mm crack width.De experimentella studier som utförts på tjocka betongbalkar som utsätts för statisk last har visat att skjuvning spelar en viktig roll i brottmekanismen. Syftet med detta examensarbete är att rekommendera lämpliga dimensioneringsmetoder för tjock betongbalkar utsatt for statisk koncentrerad last enligt Eurokod 2 med hjälp av ickelinjära finita element metod. Abaqus/Explicit användes genom att utnyttja konstitutiva materialmodeller för att fånga materialens icke-linjäritet och minskad styvhet. Tre dilatationsvinklar (30°, 38° och 45°) och två brottenergi från FIB 1990 (76 N/m) och FIB 2010 (142 N/m) tillämpas för att kontrollera deras inverkan på FE-modellerna. Dilatationsvinkel med 38° och FIB 2010 med högre brottenergi valdes i de icke-linjära finita elementanalyserna. Kontroll av FE-modellerna är baserad på ”American Concret Institutes” experimentella resultat på de tjocka betongbalkarna. Handberäkningar av tjocka betongbalkar har utförts i brott- och bruksgränstillstånd med tre dimensioneringsmetoder i Eurokod 2 nämligen balk metoden, fackverksmetoden och linjära-FE skalelementmetoden. Jämförelse har gjorts för de olika dimensioneringsmetoderna, genom att använda de armeringsdetaljer av handberäkningar i de verifierade och kalibrerade icke linjära FE-modellerna i Abaqus/Explicit. Resultaten i fråga är last för 0.3 mm handberäknad sprikvidd, FE-last för 0.3 mm sprikvidd, armeringsmängd och FE-brottlast. Jämförelse av resultaten mellan de tre dimensioneringsmetoder (balkmetod, fackverksmetod och skalelementmetod) visar att fackverksmetod är bättre design metod, eftersom det är relativt ekonomiskt med avseende på armeringsmängd, har högre lastkapacitet och last på 0.3 mm sprickvidd.
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Kim, Tae-Chung. "Analysis of Clearance Non-linearities and Vibro-impacts in Torsional Systems." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1053634349.
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Sonje, Abhijit Ravindra. "Experimental and finite element investigation into the effects of manufacturing variability on the dynamic response of a bolted interface between a bracket and a thin-walled sheet metal structure." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1546418059243072.
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Allington, Daniel. "Discourse and the reception of literature : problematising 'reader response'." Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/507.
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In my earlier work, ‘First steps towards a rhetorical hermeneutics of literary interpretation’ (2006), I argued that academic reading takes the form of an argument between readers. Four serious weaknesses in that account are its elision of the distinction between reading and discourse on reading, its inattention to non-academic reading, its exclusive focus on ‘interpretation’ as if this constituted the whole of reading or of discourse on reading, and its failure to theorise the object of literary reading, ie. the work of literature. The current work aims to address all of these problems, together with those created by certain other approaches to literary reading, with the overall objective of clearing the ground for more empirical studies. It exemplifies its points with examples drawn primarily from non-academic public discourse on literature (newspapers, magazines, and the internet), though also from other sources (such as reading groups and undergraduate literature seminars). It takes a particular (though not an exclusive) interest in two specific instances of non-academic reception: the widespread reception of Salman Rushdie’s novel The Satanic Verses as an attack on Islam, and the minority reception of Peter Jackson’s film trilogy The Lord of the Rings as a narrative of homosexual desire. The first chapter of this dissertation critically surveys the fields of reception study and discourse analysis, and in particular the crossover between them. It finds more productive engagement with the textuality of response in media reception study than in literary reception study. It argues that the application of discourse analysis to reception data serves to problematise, rather than to facilitate, reception study, but it also emphasises the problematic nature of discourse analysis itself. Each of the three subsequent chapters considers a different complex of problems. The first is the literary work, and its relation to its producers and its consumers: Chapter 2 takes the form of a discourse upon the notions of ‘speech act’ and ‘authorial intention’ in relation to literature, carries out an analysis of early public responses to The Satanic Verses, and puts in a word for non-readers by way of a conclusion. The second is the private experience of reading, and its paradoxical status as an object of public representation: Chapter 3 analyses representations of private responses to The Lord of The Rings film trilogy, and concludes with the argument that, though these representations cannot be identical with private responses, they are cannot be extricated from them, either. The third is the impossibility of distinguishing rhetoric from cognition in the telling of stories about reading: Chapter 4 argues that, though anecdotal or autobiographical accounts of reading cannot be taken at face value, they can be taken both as attempts to persuade and as attempts to understand; it concludes with an analysis of a magazine article that tells a number of stories about reading The Satanic Verses – amongst other things. Each of these chapters focuses on non-academic reading as represented in written text, but broadens this focus through consideration of examples drawn from spoken discourse on reading (including in the liminal academic space of the undergraduate classroom). The last chapter mulls over the relationship between reading and discourse of reading, and hesitates over whether to wrap or tear this dissertation’s arguments up.
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Yumer, Mehmet Ersin. "On The Non-linear Vibration And Mistuning Identification Of Bladed Disks." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/3/12611498/index.pdf.
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Forced response analysis of bladed disk assemblies plays a vital role in rotor blade design and has been drawing a great deal of attention both from research community and engine industry for more than half a century. However because of the phenomenon called &lsquomistuning&rsquo
, which destroys the cyclic symmetry of a rotor, there have been several difficulties related to forced response analysis ever since, two of which are addressed in this thesis: efficient non-linear forced response analysis of mistuned bladed disks and mistuning identification. On the nonlinear analysis side, a new solution approach is proposed studying the combined effect of non-linearity and mistuning, which is relatively recent in this research area and generally conducted with methods whose convergence and accuracy depend highly on the number of degrees of freedom where non-linear elements are attached. The proposed approach predicts nonlinear forced response of mistuned bladed disk assemblies considering any type of nonlinearity. In this thesis, special attention is given to the friction contact modeling of bladed disks which is the most common type of nonlinearity found in bladed disk assemblies. In the modeling of frictional contact a friction element which enables normal load variation and separation of the contact interface in three-dimensional space is utilized. Moreover, the analysis is carried out in modal domain where the differential equations of motions are converted to a set of non-linear algebraic equations using harmonic balance method and modal superposition technique. Thus, the number of non-linear equations to be solved is independent of the number of non-linear elements used. On the mistuning identification side, a new method is enclosed herein which makes use of neural networks to assess unknown mistuning parameters of a given bladed disk assembly from its assembly modes, thus being suitable for integrally bladed disks. The method assumes that a tuned mathematical model of the rotor under consideration is readily available, which is always the case for today&rsquo
s realistic bladed disk assemblies. A data set of selected mode shapes and natural frequencies is created by a number of simulations performed by mistuning the tuned mathematical model randomly. A neural network created by considering the number of modes, is then trained with this data set for being used to identify mistuning of the rotor from measured data. On top of these, a new adaptive algorithm is developed for harmonic balance method, several intentional mistuning patterns are investigated via excessive Monte-Carlo simulations and a new approach to locate, classify and parametrically identify structural non-linearities is introduced.
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Alqarni, Abdulelah M. Dr. "THE RELATIONSHIP BETWEEN STUDENT EVALUATIONS AND TEACHER QUALITY IN HIGH SCHOOL IN SAUDI ARABIA: ITEM RESPONSE THEORY ANALYSIS AND MULTILEVEL MODELING." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1424789095.
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Kissling, Paul Joseph. "A reader-response analysis of the reliability of selected major characters in the final form of the primary history of the Hebrew Bible." Thesis, University of Sheffield, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386910.
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Peterson, Viktor, and Zihao Wang. "Cross-comparison of Non-Linear Seismic Assessment Methods for Unreinforced Masonry Structures in Groningen." Thesis, KTH, Betongbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289386.
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A large amount of low-rise unreinforced masonry structures (URM) can be foundin Groningen, the Netherlands. More and more induced earthquakes with shortduration have been detected in this region due to gas exploitation. Local unreinforcedmasonry (URM) buildings were initially not designed for withstanding seismicactions, so that unexpected damage may occur due to their vulnerability, raising insecurityamong residents. Existing low-rise masonry buildings in Groningen can bedivided into different categories based on their characteristics. Two types of residentialmasonry buildings that fulfil the prerequisites for performing non-linear seismicassessment are chosen to be studied in this thesis project, including the terracedhouse and the detached house.The seismic assessment of structures requires the use of both a discretization methodand a seismic assessment method. The discretization method is used to translate themechanical model into a finite element model used for the numerical analysis. Severalmethods have previously shown to be applicable for seismic assessment, but thiswork investigates the implications of using a continuum model (CM) and an equivalentframe model (EFM) approach to discretization in the general-purpose finiteelement package described in DIANA-FEA-BV (2017). The continuum model approachadopted was in a previous work by Schreppers et al. (2017) validated againstexperimental results and is as such deemed representative of the physical behaviourof the mechanical models investigated. An equivalent frame model approach to beused with DIANA is proposed in the work by Nobel (2017). The continuum modelapproach uses continuum elements with a constitutive model developed for the seismicassessment of masonry structures. This constitutive model captures both shearand flexural failure mechanisms. The equivalent frame model approach uses a combinationof numerically integrated beam elements and nodal interfaces, each witha distinct constitutive model, thus decoupling the description of the flexural andshear behaviour. This approach aims to capture the macro-behaviour at the structurallevel. The applicability of the proposed equivalent frame model approach isevaluated by how well it replicates the validated continuum model approach results.The two discretization methods described are evaluated using two types of seismicassessment methods. The first seismic assessment method used consists of first performinga quasi-static non-linear pushover analysis (NLPO) on the model. Thisresults in the pushover curve, which describes the global behaviour of the modelunder an equivalent lateral load based on the fundamental mode shape of the structure.The pushover curve is then used with the N2-method described in EN1998-1iii(2004) to assess at which peak ground acceleration (PGA) that the model reachesthe near-collapse (NC) limit state. The second seismic assessment method consistsof performing dynamic non-linear time-history analyses (NLTH). This method usesrecorded accelerograms to impose the inertial forces. The PGA for the accelerogramwhere the near-collapse limit state is reached is compared to the PGA fromthe use of the N2-method. The applicability of the pushover analysis in conjunctionwith the N2-method is evaluated by how well it replicates the PGA found from thetime-history analyses and by how well it replicates local failure mechanisms.Therefore, the main objectives of this project can be described by the following twoquestions:i. To what extent can the equivalent frame method be applicable as a properdiscretization method for pushover analyses and time-history analyses oflow-rise unreinforced masonry residential buildings in the Groningen region?ii. To what extent can the non-linear pushover method be adopted toassess the seismic behaviour of low-rise unreinforced masonry residentialbuildings in the Groningen region?The applicability of the equivalent frame model showed to vary. For describing localfailure mechanisms its applicability is poor. Further work on connecting the edgepiers to transverse walls is needed. For seismic assessment using the N2-method theapplicability of the equivalent frame model approach is sensible. The conservativedisplacement capacity counteracts the fact that it is worse at describing local unloading,which produced a larger initial equivalent stiffness of the bi-linear curvesin comparison to the continuum model. For seismic assessment using the timehistorysignals, its applicability is possible. While it could show different behaviourin terms of displacement and damping forces, it still showed a similar PGA at thenear-collapse limit state for the cases at hand.The seismic assessment of the terraced and detached houses by the N2-method issimilar to the seismic prediction by applying time-history analyses. However, thereare still some variations in the initial stiffness, force capacity and displacement capacitybetween these two assessment methods due to the assumptions and limitationsin this study. Overall, considering the pros and cons of the quasi-static pushovermethod, it is deemed applicable during the seismic assessment of the unreinforcedmasonry structures in the Groningen area.
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Alqarni, Ali. "Influence of Concrete Floors on Buildings Near Fault Regions." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1608378695834876.
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George, Ryan Brandon. "Design and Analysis of a Flapping Wing Mechanism for Optimization." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2737.
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Furthering our understanding of the physics of flapping flight has the potential to benefit the field of micro air vehicles. Advancements in micro air vehicles can benefit applications such as surveillance, reconnaissance, and search and rescue. In this research, flapping kinematics of a ladybug was explored using a direct linear transformation. A flapping mechanism design is presented that was capable of executing ladybug or other species-specific kinematics. The mechanism was based on a differential gear design, had two wings, and could flap in harsh environments. This mechanism served as a test bed for force analysis and optimization studies. The first study was based on a Box-Behnken screening design to explore wing kinematic parameter design space and manually search in the direction of flapping kinematics that optimized the objective of maximum combined lift and thrust. The second study used a Box-Behnken screening design to build a response surface. Using gradient-based techniques, this surface was optimized for maximum combined lift and thrust. Box-Behnken design coupled with response surface methodology was an efficient method for exploring the mechanism force response. Both methods for optimization were capable of successfully improving lift and thrust force outputs. The incorporation of the results of these studies will aid in the design of more efficient micro air vehicles and with the ultimate goal of leading to a better understanding of flapping wing aerodynamics and the development of aerodynamic models.
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Sun, Jikai. "Simulation of Strong Ground Motions in Mashiki Town, Kumamoto, Based on the Seismic Response Analysis of Soils and the Dynamic Rupture Modeling of Sources." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263649.
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Loe, Bao Sheng. "The effectiveness of automatic item generation for the development of cognitive ability tests." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/289990.
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Research has shown that the increased use of computer-based testing has brought about new challenges. With the ease of online test administration, a large number of items are necessary to maintain the item bank and minimise the exposure rate. However, the traditional item development process is time-consuming and costly. Thus, alternative ways of creating items are necessary to improve the item development process. Automatic Item Generation (AIG) is an effective method in generating items rapidly and efficiently. AIG uses algorithms to create questions for testing purposes. However, many of these generators are in the closed form, available only to the selected few. There is a lack of open source, publicly available generators that researchers can utilise to study AIG in greater depth and to generate items for their research. Furthermore, research has indicated that AIG is far from being understood, and more research into its methodology and the psychometric properties of the items created by the generators are needed for it to be used effectively. The studies conducted in this thesis have achieved the following: 1) Five open source item generators were created, and the items were evaluated and validated. 2) Empirical evidence showed that using a weak theory approach to develop item generators was just as credible as using a strong theory approach, even though they are theoretically distinct. 3) The psychometric properties of the generated items were estimated using various IRT models to assess the impact of the template features used to create the items. 4) Joint responses and response time modelling was employed to provide new insights into cognitive processes that go beyond those obtained by typical IRT models. This thesis suggests that AIG provides a tangible solution for improving the item development process for content generation and reducing the procedural cost of generating a large number of items, with the possibility of a unified approach towards test administration (i.e. adaptive item generation). Nonetheless, this thesis focused on rule-based algorithms. The application of other forms of item generation methods and the potential for measuring the intelligence of artificial general intelligence (AGI) is discussed in the final chapter, proposing that the use of AIG techniques create new opportunities as well as challenges for researchers that will redefine the assessment of intelligence.
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Davis, Shannon Renee. ""The Buck Stops With Me" : An Analysis of Janet Reno's Defensive Discourse in Response to the Branch Davidian Crisis." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279086/.
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This study provides a genre analysis of Janet Reno's apologia in response to the Mt. Carmel disaster. Discussions of the events leading up to the crisis, Reno's rhetorical response, and relevant situational constraints and exigencies are provided.
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Hardyniec, Andrew B. "An Investigation of the Behavior of Structural Systems with Modeling Uncertainties." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56635.
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Recent advancements in earthquake engineering have caused a movement toward a probabilistic quantification of the behavior of structural systems. Analysis characteristics, such as ground motion records, material properties, and structural component behavior are defined by probabilistic distributions. The response is also characterized probabilistically, with distributions fitted to analysis results at intensity levels ranging from the maximum considered earthquake ground motion to collapse. Despite the progress toward a probabilistic framework, the variability in structural analysis results due to modeling techniques has not been considered.
This work investigates the uncertainty associated with modeling geometric nonlinearities and Rayleigh damping models on the response of planar frames at multiple ground motion intensity levels. First, an investigation is presented on geometric nonlinearity approaches for planar frames, followed by a critical review of current damping models. Three frames, a four-story buckling restrained braced frame, a four-story steel moment resisting frame, and an eight-story steel moment resisting frame, are compared using two geometric nonlinearity approaches and five Rayleigh damping models. Static pushover analyses are performed on the models in the geometric nonlinearities study, and incremental dynamic analyses are performed on all models to compare the response at the design based earthquake ground motion (DBE), maximum considered earthquake ground motion (MCE), and collapse intensity levels. The results indicate noticeable differences in the responses at the DBE and MCE levels and significant differences in the responses at the collapse level. Analysis of the sidesway collapse mechanisms indicates a shift in the behavior corresponding to the different modeling assumptions, though the effects were specific to each frame.
The FEMA P-695 Methodology provided a framework that defined the static and dynamic analyses performed during the modeling uncertainties studies. However, the Methodology is complex and the analyses are computationally expensive. To expedite the analyses and manage the results, a toolkit was created that streamlines the process using a set of interconnected modules. The toolkit provides a program that organizes data and reduces mistakes for those familiar with the process while providing an educational tool for novices of the Methodology by stepping new users through the intricacies of the process.
The collapse margin ratio (CMR), calculated in the Methodology, was used to compare the collapse behavior of the models in the modeling uncertainties study. Though it provides a simple scalar quantity for comparison, calculation of the CMR typically requires determination of the full set of incremental dynamic analysis curves, which require prohibitively large analysis time for complex models. To reduce the computational cost of calculating the CMR, a new parallel computing method, referred to as the fragility search method, was devised that uses approximate collapse fragility curves to quickly converge on the median collapse intensity value. The new method is shown to have favorable attributes compared to other parallel computing methods for determining the CMR.Ph. D.
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Kayikci, Duygu y. "The Behavior of Moment Resisting Steel Frames Under Seismic Excitation with Variation of Geometric Dimensions of Architectural Setbacks." Scholarly Repository, 2011. http://scholarlyrepository.miami.edu/oa_dissertations/583.
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This study investigates seismic response of the Moment-Resisting-Steel Frames (MRSF) with the architectural setbacks. The main objective of the study is to understand the variation of the elastic and inelastic, static and dynamic behavior with changes in the geometric dimensions of the tower portion. A second objective of the study is to determine the adequacy of the analysis procedures of various rigors, specified in current seismic design provision, in predicting those behaviors for MRSF with various size of setback. The analytical study is conducted using a regular and 16 irregular models to capture all possible combinations of configuration of setback in five-story, five-bay MRSFs. An irregular model is developed by gradually changing the horizontal and vertical dimensions of the tower portion of the regular base 2D frame-model. All models were designed for (a) equal global displacement and uniform distribution of inter-story drift under First-Mode (FM) lateral force distribution pattern at first significant yield, and (b) equal period of vibration at the first mode, using Nonlinear Static Seismic analysis procedure. Among the conclusions derived from the research is that the variation of (a) the elastic and inelastic inter-story drift, the ductility demand for the top three stories, and (b) the elastic and inelastic global displacement exhibited a pattern similar to the variation of the FM participation factor at the roof, PF1Φr,1. The square-root-of-sum-of-square (SRSS) distribution provided accurate estimates of elastic story shear and inter-story drift demand as well as the story yield strength and drift.
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Fitoz, Hatice Eda. "Response Of Asymmetric Isolated Buildings Under Bi-directionalexcitations Of Near-fault Ground Motions." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614121/index.pdf.
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Isolator displacements, floor accelerations, roof displacements, base shear and
torsional moments are basic parameters that are considered in the design of
seismically isolated structures. The aim of this study is to evaluate the effects of bidirectional
earthquake excitations of near fault records on the response of base
isolated structures in terms of basic parameters mentioned above. These parameters
computed from nonlinear response history analysis (RHA) and they are compared
with the parameters computed from equivalent lateral force procedure (ELF). Effect
of asymmetry in superstructure is also examined considering mass eccentricity at
each floor level. Torsional amplifications in isolator displacements, floor
accelerations, roof displacements and base shear are compared for different level of
eccentricities. Two buildings with different story heights are used in the analyses.The building systems are modeled in structural analysis program SAP2000. The
scaling of ground motion data are taken from the study of &ldquoResponse of Isolated Structures Under Bi-directional Excitations of Near-fault ground Motions&rdquo
(Ozdemir, 2010). Each ground motion set (fault normal and fault parallel) are applied simultaneously for different range of effective damping of lead rubber bearing (LRB) and for different isolation periods.
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Isbiliroglu, Levent. "Strategy for Selecting Input Ground Motion for Structural Seismic Demand Analysis." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAU009/document.
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Les signaux accélérométriques enregistrés lors de l’occurrence d’un événement sismique est très large présentent une forte variabilité, par conséquent ils ne sont pas utilisé dans les analyse dynamiques de tenue sismique des structures. En effet, l’utilisation des accélérogrammes réels, pour les analyses dynamiques non linéaires, s’avère couteuse en termes de temps de calcul. La pratique courante prévoit la minimisation (voir suppression) de telle variabilité, mais les conséquences d’une telle opération sur la réponse des structures ne sont pas clairement indiquées. L’étude ci-présente a pour scope la quantification de l’impact des méthodes de sélection qui gardent la variabilité du signal sur les résultats de l’analyse de la réponse des structures (exprimée en termes d’engineering demand parameters EDPs). En particulier les questions suivantes seront investiguées :Quel est le niveau de variabilité des accélérogrammes réels et comment ce niveau est modifié par les techniques couramment utilisées ?Quelle est l’impact de la variabilité sur la réponse de plusieurs types de structures ?Pour un scénario sismique donné, un spectre cible est défini à partir de plusieurs équation de prédiction du mouvement sismique, sélection parmi celles disponibles en littérature. Les accélérogrammes sont sélectionnés à partir de quatre familles d’accélérogrammes, chacune relative à une méthode de modification : réels (enregistrés); mise à l’échelle (multiplication, par un facteur) ; calés aux spectres cibles avec large tolérance ; calés aux spectres cibles dans une plage de tolérance étroite.Chaque jeu de signaux est composé de cinq accélérogrammes et la sélection des signaux est faite en tenant compte de deux sources de variabilité : la variabilité au sein de chaque jeu de données (intraset), et la variabilité entre les différents jeux de données (interset) tous compatibles avec le même spectre cible. Les tests sur les EDPs menés sur les signaux accélérométriques réels mènent à la quantification de la variabilité naturelle (pour le scénario considéré). Les analyses basées sur les signaux réels sont utilisés comme benchmark afin d’évaluer non seulement de combien la distribution des EDPs (en termes de valeur moyenne et variabilité) est réduite par les différentes méthodes testées, mais aussi d’évaluer l’impact des choix de l’équation de prédiction du mouvement, des plages de tolérance, du nombre d’accélérogrammes constituant chaque jeu, du nombre de jeux, de le scope de l’analyse structurale et le modèle de structure.Ce travaille nous conduit à conclure que un seul jeu d’accélérogramme, tel qu’utilisé dans la pratique courante, est insuffisant pour assurer le niveau d’EDPs indépendamment de la méthode de modification utilisés, cela est lié à la variabilité des signaux et entre les jeux d’accélérogrammes. Les signaux réels, compatibles avec le spectre définis pour le scénario sismique, are l’option plus réaliste pour l’analyse dynamique non-linéaire ; si une méthode de modification du signal est nécessaire, la plus adaptées dépend du scope de l’analyse spectrale et du modèle. Le choix de l’équation de prédiction du mouvement sismique utilisée pour définir le spectre cible impacte significativement les caractéristiques des mouvements sismiques et des EDPs. Cette observation ne dépend pas de la stratégie de de modification du signalThe observed variability is very large among natural earthquake records, which are not consolidated in the engineering applications due to the cost and the duration. In the current practice with the nonlinear dynamic analysis, the input variability is minimized, yet without clear indications of its consequences on the output seismic behavior of structures. The study, herein, aims at quantifying the impact of ground motion selection with large variability on the distribution of engineering demand parameters (EDPs) by investigating the following questions:What is the level of variability in natural and modified ground motions?What is the impact of input variability on the EDPs of various structural types?For a given earthquake scenario, target spectra are defined by ground motion prediction equations (GMPEs). Four ground motion modification and selection methods such as (1) the unscaled earthquake records, (2) the linearly scaled real records, (3) the loosely matched spectrum waveforms, and (4) the tightly matched waveforms are utilized. The tests on the EDPs are performed on a record basis to quantify the natural variability in unscaled earthquake records and the relative changes triggered by the ground motion modifications.Each dataset is composed by five accelerograms; the response spectrum compatible selection is then performed by considering the impact of set variability. The intraset variability relates to the spectral amplitude dispersion in a given set, and the interset variability relates to the existence of multiple sets compatible with the target.The tests on the EDPs are performed on a record basis to quantify the natural variability in unscaled earthquake records and the relative changes triggered by the ground motion modifications. The distributions of EDPs obtained by the modified ground motions are compared to the observed distribution by the unscaled earthquake records as a function of ground motion prediction equations, objective of structural analysis, and structural models.This thesis demonstrates that a single ground motion set, commonly used in the practice, is not sufficient to obtain an assuring level of the EDPs regardless of the GMSM methods, which is due to the record and set variability. The unscaled real records compatible with the scenario are discussed to be the most realistic option to use in the nonlinear dynamic analyses, and the ‘best’ ground motion modification method is demonstrated to be based on the EDP, the objective of the seismic analysis, and the structural model. It is pointed out that the choice of a GMPE can provoke significant differences in the ground motion characteristics and the EDPs, and it can overshadow the differences in the EDPs obtained by the GMSM methods
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Allahverdiyev, Rovshan. "Effects of beam configuration on dynamic properties and seismic performances of multi-storey frame building models." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Find full textAbstract:
The present study aims at comparing the dynamic properties and seismic performances offered by reinforced concrete frame structures characterised by different beams distribution.
Multi-storey regular frame buildings are considered as reference structures. Different models are then developed according to various layout of the beams (x-direction is the longitudinal direction, whilst y-direction is the transversal one): (1) beams placed along the x-direction at the odd storeys and placed along the y-direction at the even storeys; (2) beams placed along the y-direction at the odd storeys and placed along the x-direction at the even storeys; (3) and (4) alternating beams every two storeys; (5) beams placed along the x-direction at all storeys; (6) beams placed along the y-direction at all storeys; (7) complete three-dimensional frame with beams placed along both the x- and the y-direction at all storeys. In all models, smaller perimeter beams are placed along the direction orthogonal to the one of the main beams.
Modal analysis has been conducted to evaluate the influence of beams distribution on the period of vibration. Response spectrum and time-history dynamic analyses have been carried out to assess the effects of beams distribution on the base shear and base bending moments, top-storey displacements, interstorey displacements and floor accelerations.
On the contrary of what could be expected, the results indicate that structures with beams alternating every storey do not behave unfavorably with respect to the complete three-dimensional frames. In more detail, two effects may be clearly recognized: one associated to the period and one associated to the static scheme. The former acting basically on the base shear; the latter acting mainly on the base bending moment. The understanding of the influence of beams distribution on frame structures is useful when dealing with seismic vulnerability assessment of existing buildings and design of new buildings.