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- Title
- Disrupting methamphetamine associated memory by targeting synaptic dynamics.
- Creator
- Zigmond, Zachary, Miller, Courtney, Young, Erica, Quintyne, Nicholas, Harriet L. Wilkes Honors College
- Abstract/Description
-
Methamphetamine (METH) is addictive and associated with a high rate of relapse. One relapse trigger is re-experiencing drug-associated contextual associations. Therefore it is possible that, by targeting METH-associated contextual memories, drug seeking behavior can be inhibited. Recent evidence has suggested that memory formation relies on actin polymerization, which allows dendritic spines to undergo structural and functional plasticity, key components of memory. To see if actin...
Show moreMethamphetamine (METH) is addictive and associated with a high rate of relapse. One relapse trigger is re-experiencing drug-associated contextual associations. Therefore it is possible that, by targeting METH-associated contextual memories, drug seeking behavior can be inhibited. Recent evidence has suggested that memory formation relies on actin polymerization, which allows dendritic spines to undergo structural and functional plasticity, key components of memory. To see if actin polymerization could be a target for the extinction of METH seeking memories we inhibited actin polymerization in animals that had been trained in either METH or food associated conditioned place preference. Pretest inhibition of actin cycling in the basolateral amygdala complex produced immediate and persistent extinction of METH seeking behavior. Additionally, inhibiting actin polymerization 24hrs before testing disrupted seeking behavior for METH but not food. These results indicate that METH-associated memories are selectively vulnerable to disruption through inhibition of actin dynamics.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA00003542
- Format
- Document (PDF)
- Title
- Three Assassins: Women, Revolution and Violence in Modern World History.
- Creator
- Zigmond, Ashleah, Ely, Christopher, McGetchin, Douglas, Harriet L. Wilkes Honors College, Florida Atlantic University
- Abstract/Description
-
This thesis examines three women who committed the unprecedented crime of attempting to assassinate a key male figure in three separate times and places. It involves the government’s and society’s reaction and implications about the role of gender in the violent deeds transforming society at times of revolutionary upheaval. The women examined are Charlotte Corday from eighteenth century France, Vera Zasulich from nineteenth century Russia, and Shi Jianqiao from twentieth century China. These...
Show moreThis thesis examines three women who committed the unprecedented crime of attempting to assassinate a key male figure in three separate times and places. It involves the government’s and society’s reaction and implications about the role of gender in the violent deeds transforming society at times of revolutionary upheaval. The women examined are Charlotte Corday from eighteenth century France, Vera Zasulich from nineteenth century Russia, and Shi Jianqiao from twentieth century China. These women shared numerous qualities that, when combined, provided the women with the ability to see themselves as equals in the patriarchal societies in which they lived, allowing them to participate in the typically male dominated public sphere.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/fau/fd/FA00003610_0
- Format
- Document (PDF)
- Title
- Interview with Natan Zielon.
- Creator
- Zielon, Natan (Interviewee), Gladstone, Devon (Interviewer)
- Date Issued
- 2010-10-01
- PURL
- http://purl.flvc.org/fau/fd/FADT3358461
- Subject Headings
- Oral histories --Florida, Oral history, World War II, Wodzisław (Poland), Sedziszow (Poland), Buchenwald (Concentration camp), Skarzysko-Kamienna (Concentration camp)
- Format
- Set of related objects
- Title
- Quality vs Quantity.
- Creator
- Ziegler, Kyle, Auguste, Derream, Escaleras, Monica
- Abstract/Description
-
As the demand for food increases, food makers must increase production; however, there comes a point when one must consider what is sacrificed for such an increase in mass production of food. Food is now evolving, preferences are varying from natural tastes to unnatural alterations due to chemical additives. We felt more research is needed to understand what motivates consumers to purchase varying types of foods. To understand consumers’ views on food preferences, we developed an online...
Show moreAs the demand for food increases, food makers must increase production; however, there comes a point when one must consider what is sacrificed for such an increase in mass production of food. Food is now evolving, preferences are varying from natural tastes to unnatural alterations due to chemical additives. We felt more research is needed to understand what motivates consumers to purchase varying types of foods. To understand consumers’ views on food preferences, we developed an online survey with fifteen questions and collected responses from 498 people. Our findings show a statistically significant difference between people of different gender, age, and regions regarding motivations to purchase food and food labeling. With this knowledge, we may better understand what people of different demographics feel regarding the current state of food wellness, and why they might prefer certain actions over others due to their diverse backgrounds.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FAU_SR00000057
- Subject Headings
- College students --Research --United States.
- Format
- Document (PDF)
- Title
- High Resolution Population Distribution Estimates for Improved Decision Making, With a Case Study of Sea-Level Rise Vulnerability in Boca Raton, Florida.
- Creator
- Ziegler, Hannes Moritz, Xie, Zhixiao, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Geosciences
- Abstract/Description
-
Planners and managers often rely on coarse population distribution data from the census for addressing various social, economic, and environmental problems. In the analysis of physical vulnerabilities to sea-level rise, census units such as blocks or block groups are coarse relative to the required decision-making application. This study explores the benefits offered from integrating image classification and dasymetric mapping at the household level to provide detailed small area population...
Show morePlanners and managers often rely on coarse population distribution data from the census for addressing various social, economic, and environmental problems. In the analysis of physical vulnerabilities to sea-level rise, census units such as blocks or block groups are coarse relative to the required decision-making application. This study explores the benefits offered from integrating image classification and dasymetric mapping at the household level to provide detailed small area population estimates at the scale of residential buildings. In a case study of Boca Raton, FL, a sea-level rise inundation grid based on mapping methods by NOAA is overlaid on the highly detailed population distribution data to identify vulnerable residences and estimate population displacement. The enhanced spatial detail offered through this method has the potential to better guide targeted strategies for future development, mitigation, and adaptation efforts.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004670
- Subject Headings
- City planning -- Remote sensing, Community development, Urban -- Florida -- Boca Raton, Geographic information systems, Population -- Geographic information systems -- Florida -- Boca Raton, egional planning -- Florida -- Boca Raton, Spatial analysis (Statistics), Urban geography -- Remote sensing
- Format
- Document (PDF)
- Title
- INTRASEXUAL SELECTION AND THE ELABORATION OF A MATING SIGNAL IN THE BACHMAN’S SPARROW (PEUCEA AESTIVALIS).
- Creator
- Ziadi, Paula, Anderson, Rindy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Vocal communication is central to the coordination of social behavior in many vertebrate species, and it has been particularly well studied in songbirds, which use their songs in different contexts to convey information about the singer or its environment (Catchpole and Slater 2008; Alger et al. 2016). While it is widely accepted that the songs of oscine passerine birds (the songbirds) have two main social functions: intrasexual competition, and courtship (Catchpole and Slater 2008), the...
Show moreVocal communication is central to the coordination of social behavior in many vertebrate species, and it has been particularly well studied in songbirds, which use their songs in different contexts to convey information about the singer or its environment (Catchpole and Slater 2008; Alger et al. 2016). While it is widely accepted that the songs of oscine passerine birds (the songbirds) have two main social functions: intrasexual competition, and courtship (Catchpole and Slater 2008), the evolution of large and complex song repertoires remains an evolutionary puzzle (Byers and Kroodsma 2009). The question is: why do some songbird species produce an elaborate vocal repertoire, while other species carry out courtship and competition with a far smaller and simpler repertoire? In this thesis I examine the adaptive value (social function) of song in malemale competition with an eye toward understanding how intrasexual selection may have driven the elaboration of the male Bachman’s sparrow (Peucea aestivalis) vocal repertoire.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013352
- Subject Headings
- Bachman's sparrow, Songbirds--Behavior, Songbirds--Vocalization, Birds--Sexual behavior
- Format
- Document (PDF)
- Title
- Remittances, Health and Education: A Cross-Country Study.
- Creator
- Zhunio, Maria Cristina, Vishwasrao, Sharmila, Florida Atlantic University
- Abstract/Description
-
This study examines the effects of epistemic motives and individual social structure (strength of social ties) on individual actions. lt has been suggested that the informal structure of relations that develops within firms affects the actions of individuals perhaps more so than formal structure. Ifthis is true, when studying organizations perhaps more effort should be given to examining the effects of the structure of social relations within the firm . This study has attempted to take the...
Show moreThis study examines the effects of epistemic motives and individual social structure (strength of social ties) on individual actions. lt has been suggested that the informal structure of relations that develops within firms affects the actions of individuals perhaps more so than formal structure. Ifthis is true, when studying organizations perhaps more effort should be given to examining the effects of the structure of social relations within the firm . This study has attempted to take the first steps in beginning to systematically study identifiable and predictable effects of the informal structure of relations on the behavior of individuals. During the process of examining the etfects of epistemic motives and individual social structure on the actions of individuals, two important questions were addressed. First, what are the effects of epistemic motives on the formation of individual social structure? The findings of this study suggest that the need for closure and the need for cognition affect the formation of individual social structure in different and identifiable ways. In addition, the level of epistemic motivation atiects the degree to which social interactions affect tie strength. The second question is what are the effects of individual social structures on individual actions? The findings of this study suggest that the tie strength of an individual's social structure appears to affect interdependent actions; but, tie strength does not affect independent actions. In addition, an understanding about individuals' inclinations to take interdependent or independent actions is enhanced when the effects of both epistemic motives and social structure are considered. The findings of this study suggest that information about the epistemic motives of employees can provide insight into the fonnation of the individual social structures and the intrinsic desire of employees to take interdependent or independent actions. The effects of epistemic motives and individual social structure on individual actions, the organizing process and the formulation and implementation of strategies are discussed.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00000311
- Subject Headings
- Emigration and Immigration--Economic Aspects, Emigrant Remittances, Emigration and Immigration--Government Policy
- Format
- Document (PDF)
- Title
- Application of MoM: Scattering calculations using condition number.
- Creator
- Zhuang, Zhijun., Florida Atlantic University, Bagby, Jonathan S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Computational accuracy is widely recognized as a critical issue in applied electromagnetics. Increasing computational power is being applied to solve more complex electromagnetic systems with an emphasis on computational accuracy. The work of this thesis is focused on the implementation of Method of Moments (MoM) to integral equation formulations. The goal of this effort is to use what is known as condition number, and, a heuristic rule-of-thumb is applied to investigate the computational...
Show moreComputational accuracy is widely recognized as a critical issue in applied electromagnetics. Increasing computational power is being applied to solve more complex electromagnetic systems with an emphasis on computational accuracy. The work of this thesis is focused on the implementation of Method of Moments (MoM) to integral equation formulations. The goal of this effort is to use what is known as condition number, and, a heuristic rule-of-thumb is applied to investigate the computational accuracy of MoM in numerical electromagnetics. Other possible applications of condition number of the MoM matrix are also indicated.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15719
- Subject Headings
- Electromagnetism, Moments method (Statistics), Electromagnetic theory, Integral equations--Numerical solutions
- Format
- Document (PDF)
- Title
- Feasibility of using carbon fiber reinforced plastic tendons in prestressed concrete Double-Tee bridge system.
- Creator
- Zhuang, Ming., Florida Atlantic University, Arockiasamy, Madasamy, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
One of the major problems the construction industry faces today is corrosion of reinforcing and prestressing steel, which significantly affects the durability of concrete structures. Fiber reinforced plastics (FRPs) are highly regarded as prospective replacement for steel in prestressed concrete structures under corrosive environment. This investigation was conducted to establish the feasibility of using Carbon Fiber Composite (CFC) cables as reinforcing/prestressing elements in concrete...
Show moreOne of the major problems the construction industry faces today is corrosion of reinforcing and prestressing steel, which significantly affects the durability of concrete structures. Fiber reinforced plastics (FRPs) are highly regarded as prospective replacement for steel in prestressed concrete structures under corrosive environment. This investigation was conducted to establish the feasibility of using Carbon Fiber Composite (CFC) cables as reinforcing/prestressing elements in concrete bridge structures. Besides investigating durability of CFC cables and pretensioned concrete beams with CFC cables in adverse environments (alkali and seawater), flexure and shear tests were performed on single Double-Tee beams, together with service load behavior, fatigue strength and ultimate load capacity tests on a half scale model Double-Tee girder bridge system prestressed with CFC cables. Exposure to seawater and alkali environments has no adverse effect on the strength of the CFRP tendons as well as the pretensioned beams with CFRP. Based on the flexural strength tests on Double-Tee beams, the bond between CFRP tendons and concrete is satisfactory. The Double-Tee bridge system exhibited good fatigue resistance and adequate ductility under ultimate load conditions. The ultimate load capacity of the bridge is approximately three times the service load corresponding to two HS20-44 trucks and equals 2.4 times the first crack load. Finite element analyses were carried out to predict elastic deformations and collapse load of the Double-Tee bridge prestressed with CFC cables. Feasibility of using CFC cables in bridge structures is assessed based on the experimental and analytical parameters such as deflections, strains, crack distributions and crack widths.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/12465
- Subject Headings
- Carbon fibers, Composite construction, Fiber reinforced plastics, Bridges, Iron and steel, Reinforced concrete construction, Prestressed concrete construction
- Format
- Document (PDF)
- Title
- The effects of the chelating agents on the 123-superconductor.
- Creator
- Zhuang, Huifang, Florida Atlantic University, Carraher, Charles E.
- Abstract/Description
-
This study reports the initial evaluation of the effect of selected chelating agents on the 123-superconductor. For the chelating agents oxalic acid and disodium oxalate, the extent and the rate of magnetic susceptibility decrease are discussed with respect to their concentration, site of chelation, exposure time and selectivity. The magnetic susceptibility measurements were carried out with a Superconductor Characterization Cryostat and the surface analysis was accomplished by employing...
Show moreThis study reports the initial evaluation of the effect of selected chelating agents on the 123-superconductor. For the chelating agents oxalic acid and disodium oxalate, the extent and the rate of magnetic susceptibility decrease are discussed with respect to their concentration, site of chelation, exposure time and selectivity. The magnetic susceptibility measurements were carried out with a Superconductor Characterization Cryostat and the surface analysis was accomplished by employing Auger Electron Spectroscopy (AES) and X-Ray Photoelectron Spectroscopy (XPS). The results show that the solution containing oxalic acid can remove copper atoms from the superconductor surface. The extent and the rate of superconductivity decrease can be controlled by changes in concentration, addition sequence and exposure time.
Show less - Date Issued
- 1990
- PURL
- http://purl.flvc.org/fcla/dt/14627
- Subject Headings
- High temperature superconductors, Chelates
- Format
- Document (PDF)
- Title
- NEIGHBORING NEAR MINIMUM-TIME CONTROLS WITH DISCONTINUITIES AND THE APPLICATION TO THE CONTROL OF MANIPULATORS (PATH-PLANNING, TRACKING, FEEDBACK).
- Creator
- Zhuang, Hanqi, Florida Atlantic University, Hamano, Fumio, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis presents several algorithms to treat the problem of closed-loop near minimum-time controls with discontinuities. First, a neighboring control algorithm is developed to solve the problem in which controls are bounded by constant constraints. Secondly, the scheme is extended to account for state-dependent control constraints. And finally, a path tracking algorithm for robotic manipulators is presented, which is also a neighboring control algorithm. These algorithms are suitable for...
Show moreThis thesis presents several algorithms to treat the problem of closed-loop near minimum-time controls with discontinuities. First, a neighboring control algorithm is developed to solve the problem in which controls are bounded by constant constraints. Secondly, the scheme is extended to account for state-dependent control constraints. And finally, a path tracking algorithm for robotic manipulators is presented, which is also a neighboring control algorithm. These algorithms are suitable for real time controls because the on-line computations involved are relatively simple. Simulation results show that these algorithms work well despite the fact that the prescribed final points can not be reached exactly.
Show less - Date Issued
- 1986
- PURL
- http://purl.flvc.org/fcla/dt/14326
- Subject Headings
- Manipulators (Mechanism), Control theory, Algorithms
- Format
- Document (PDF)
- Title
- Kinematic modeling, identification and compensation of robot manipulators.
- Creator
- Zhuang, Hanqi, Florida Atlantic University, Hamano, Fumio, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Theoretical and practical issues of kinematic modeling, measurement, identification and compensation are addressed in this dissertation. A comprehensive robot calibration methodology using a new Complete and Parametrically Continuous (CPC) kinematic model is presented. The dissertation focuses on model-based robot calibration techniques. Parametric continuity of a kinematic model is defined and discussed to characterize model singularity. Irreducibility is defined to facilitate error model...
Show moreTheoretical and practical issues of kinematic modeling, measurement, identification and compensation are addressed in this dissertation. A comprehensive robot calibration methodology using a new Complete and Parametrically Continuous (CPC) kinematic model is presented. The dissertation focuses on model-based robot calibration techniques. Parametric continuity of a kinematic model is defined and discussed to characterize model singularity. Irreducibility is defined to facilitate error model reduction. Issues of kinematic parameter identification are addressed by utilizing generic forms of linearized kinematic error models. The CPC model is a complete and parametrically continuous kinematic model capable of describing geometry and motion of a robot manipulator. Owing to the completeness of the CPC model, the transformation from the base frame to the world frame and from the tool frame to the last link frame can be modeled with the same modeling convention as the one used for internal link transformations. Due to the parametric continuity of the CPC model, numerical difficulties in kinematic parameter identification using error models are reduced. The CPC model construction, computation of the link parameters from a given link transformation, inverse kinematics, transformations between the CPC model and the Denavit-Hartenberg model, and linearized CPC error model construction are investigated. New methods for self-calibration of a laser tracking coordinate-measuring-machine are reported. Two calibration methods, one based on a four-tracker system and the other based on three trackers with a precision plane, are proposed. Iterative estimation algorithms along with simulation results are presented. Linear quadratic regulator (LQR) theory is applied to design robot accuracy compensators. In the LQR algorithm, additive corrections of joint commands are found without explicitly solving the inverse kinematic problem for an actual robot; a weighting matrix and coefficients in the cost function can be chosen systematically to achieve specific objective such as emphasizing the positioning accuracy of the end-effector over its orientation accuracy and vice versa and taking into account joint travelling limits as well as singularity zones of the robot. The results of the kinematic identification and compensation experiments using the PUMA robot have shown that the CPC modeling technique presented in this dissertation is a convenient and effective means for accuracy improvements of industrial robots.
Show less - Date Issued
- 1989
- PURL
- http://purl.flvc.org/fcla/dt/12243
- Subject Headings
- Robotics, Manipulators (Mechanism)
- Format
- Document (PDF)
- Title
- Finite element modeling for dislocation generation in semiconductor crystals grown from the melt.
- Creator
- Zhu, Xinai., Florida Atlantic University, Tsai, Chi-Tay, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
Dislocations in Gallium Arsenide (GaAs) and Indium Phosphide (InP) single crystals are generated by excessive stresses that are induced during the crystal growth process, and the fabrication and packaging of microelectronic devices/circuits. The presence of dislocations has adverse effects on the performance, lifetime and reliability of the GaAs and InP-based devices/circuits. It is well known that dislocation density can be significantly reduced by doping impurity atoms into the GaAs and InP...
Show moreDislocations in Gallium Arsenide (GaAs) and Indium Phosphide (InP) single crystals are generated by excessive stresses that are induced during the crystal growth process, and the fabrication and packaging of microelectronic devices/circuits. The presence of dislocations has adverse effects on the performance, lifetime and reliability of the GaAs and InP-based devices/circuits. It is well known that dislocation density can be significantly reduced by doping impurity atoms into the GaAs and InP crystal and/or decreasing the thermal stresses in these crystals during their growth process. In order to reduce the dislocation density generated in the GaAs and InP crystals, the influence of crystal growth parameters and doping impurity atoms on the dislocations reduction in GaAs and InP crystals has to be understood. Therefore, a transient finite element model was developed to simulate the dislocation generation in GaAs and InP crystals grown from the melt. A viscoplastic constitutive equation that couples a microscopic dislocation density with a macroscopic plastic deformation is employed to formulate this transient finite element model, where the dislocation density is considered as an internal state variable and the doping impurity is represented by a drag-stress in this constitutive model. GaAs and InP single crystals grown by the vertical gradient freeze (VGF) process were adopted as examples to study the influences of doping impurity and growth parameters on dislocations generated in these grown crystal. The calculated results show that doping impurity can significantly reduce dislocation generation and produces low-dislocation-density or dislocation free GaAs and InP single crystals. It also shows that the dislocations generated in GaAs and InP crystals increase as the crystal diameter and imposed temperature gradient increase, but do not change or increase slightly as the crystal growth rate increases. Therefore, this finite element model can be effectively used by crystal growers to select acceptable levels of doping impurity, crystal diameter, temperature gradient, and growth rate to produce the lowest dislocation density in GaAs and InP crystals through a thorough numerical investigation using this developed finite element model.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/12072
- Subject Headings
- Dislocations in crystals, Gallium arsenide semiconductors, Indium phosphide, Metal crystals--Growth
- Format
- Document (PDF)
- Title
- Deterministic, stochastic and convex analyses of one- and two-dimensional periodic structures.
- Creator
- Zhu, Liping., Florida Atlantic University, Lin, Y. K., Elishakoff, Isaac, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
The periodic structures considered in the dissertation are one-dimensional periodic multi-span beams, and two-dimensional periodic grillages with elastic interior supports. The following specific topics are included: (1) Deterministic Vibration--Exact solutions are obtained for free vibrations of both multi-span beams and grillages, by utilizing the wave propagation concept. The wave motions at the periodic supports/nodes are investigated and the dispersion equations are derived from which...
Show moreThe periodic structures considered in the dissertation are one-dimensional periodic multi-span beams, and two-dimensional periodic grillages with elastic interior supports. The following specific topics are included: (1) Deterministic Vibration--Exact solutions are obtained for free vibrations of both multi-span beams and grillages, by utilizing the wave propagation concept. The wave motions at the periodic supports/nodes are investigated and the dispersion equations are derived from which the natural frequencies of the periodic structures are determined. The emphasis is placed on the calculation of mode shapes of both types of periodic structures. The general expressions for mode shapes with various boundary conditions are obtained. These mode shapes are used to evaluate the exact dynamic response to a convected harmonic loading. (2) Stochastic Vibration--A multi-span beam under stochastic acoustic loading is considered. The exact analytical expressions for the spectral densities are derived for both displacement and bending moment by using the normal mode approach. Nonlinear vibration of a multi-span beam with axial restraint and initial imperfection are also investigated. In the latter case, the external excitation is idealized as a Gaussian white nose. An expression for the joint probability density function in the generalized coordinates is obtained and used to evaluate the mean square response of a multi-span beam system. (3) Convex Modeling of Uncertain Excitation Field--It is assumed that the parameters of the stochastic excitation field are uncertain and belong to a multi-dimensional convex set. A new approach is developed to determine the multi-dimensional ellipsoidal convex set with a minimum volume. The most and least favorable responses of a multi-span beam are then determined for such a convex set, corresponding to a stochastic acoustic field. The procedure is illustrated in several examples.
Show less - Date Issued
- 1994
- PURL
- http://purl.flvc.org/fcla/dt/12366
- Subject Headings
- Grillages (Structural engineering), Girders--Vibration, Wave-motion, Theory of, Vibration
- Format
- Document (PDF)
- Title
- Hybrid probabilistic and convex modeling of excitation and response of periodic structures.
- Creator
- Zhu, L. P., Elishakoff, Isaac
- Abstract/Description
-
In this paper, a periodic finite-span beam subjected to the stochastic acoustic pressure with bounded parameters is investigated. Uncertainty parameters exist in this acoustic excitation due to the deviation or imperfection. First, a finite-span beams subjected to the random acoustic pressure field are studied, the exact analytic forms of the cross-spectral density of both the transverse displacement and the bending moment responses of the structure are formulated. The combined probabilistic...
Show moreIn this paper, a periodic finite-span beam subjected to the stochastic acoustic pressure with bounded parameters is investigated. Uncertainty parameters exist in this acoustic excitation due to the deviation or imperfection. First, a finite-span beams subjected to the random acoustic pressure field are studied, the exact analytic forms of the cross-spectral density of both the transverse displacement and the bending moment responses of the structure are formulated. The combined probabilistic and convex modeling of acoustic excitation appears to be most suitable, since there is an insufficient information available on the acoustic excitation parameters, to justify the totally probabilitic analysis. Specifically, we postulate that the uncertainty parameters in the acoustic loading belong to a bounded, convex set. In the special case when this convex set is an ellipsoid, closed form solutions are obtained for the most and least favorable mean square responses of both the transverse displacement and bending moment of the structure. Several finite-span beams are exemplified to gain insight into proposal methodology.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fau/fd/FAUIR000090
- Format
- Citation
- Title
- Decay for time-dependent Schroedinger equations.
- Creator
- Zhou, Zhen, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Mathematical Sciences
- Abstract/Description
-
We study the decay in time of solutions of Schrodinger equations of the type du/du=idelta u+iV(t)u, establishing that for small potentials and initial data in L1 the solution u satisfies sup[u(x,t)](x element of R)
Show moreWe study the decay in time of solutions of Schrodinger equations of the type du/du=idelta u+iV(t)u, establishing that for small potentials and initial data in L1 the solution u satisfies sup[u(x,t)](x element of R)Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/12463
- Subject Headings
- Mathematics
- Format
- Document (PDF)
- Title
- Emergence of epilepsy in a transgenic mouse strain that over-expressesbrain- derived neurotrophic factor in theforebrain.
- Creator
- Zhou, Wei Hui, Isgor, Ceylan, Office of Undergraduate Research and Inquiry
- Abstract/Description
-
Structural changes that alter hippocampal functional circuitry are implicated in learning impairments, mood disorders and epilepsy. Failure to properly gate neuronal activity arriving in hippocampus may be critical in developing synaptic circuits that generate seizures due to sustained elevations in hippocampal BDNF. Our data shows higher number of synaptic contact points (spines) on dendritic surfaces of granule cells in 2-3 month-old TgBDNF mice compared to WT mice, suggesting that there is...
Show moreStructural changes that alter hippocampal functional circuitry are implicated in learning impairments, mood disorders and epilepsy. Failure to properly gate neuronal activity arriving in hippocampus may be critical in developing synaptic circuits that generate seizures due to sustained elevations in hippocampal BDNF. Our data shows higher number of synaptic contact points (spines) on dendritic surfaces of granule cells in 2-3 month-old TgBDNF mice compared to WT mice, suggesting that there is increased cortical input onto granule cells. The dysregulation in mature GC circuitry in seizure dormant period in TgBDNF mice indicates early seizure susceptibility. Both mature GCs and immature GCs will show structural alterations in their input and/or output regions in TgBDNF mice long before full motor seizures are detectable pinpointing early dysregulations in the gating properties of these input neurons to hippocampus, favoring enhanced information processing and propagation. These collective results will help pinpoint intervention targets for seizure prevention.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00005609
- Subject Headings
- College students --Research --United States.
- Format
- Document (PDF)
- Title
- Blast/explosion resistant analysis of composite steel girder bridge system.
- Creator
- Zhou, Fang., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The design of bridge structures to resist explosive loads has become more of a concern to the engineering community. This thesis proposes a method to evaluate the effects of conventional blast loads on a two span continuous composite steel girder bridge system. The bridge design is based on AASHTO LRFD method. Resistance capacities of bridge deck and composite steel girder are calculated according to AASHTO specifications. Equivalent blast pressures on the bridge components are obtained....
Show moreThe design of bridge structures to resist explosive loads has become more of a concern to the engineering community. This thesis proposes a method to evaluate the effects of conventional blast loads on a two span continuous composite steel girder bridge system. The bridge design is based on AASHTO LRFD method. Resistance capacities of bridge deck and composite steel girder are calculated according to AASHTO specifications. Equivalent blast pressures on the bridge components are obtained. Response and performance of concrete deck, steel girders, and supporting piers are evaluated under typical blast loads. The blast induced force in the bridge components are computed in the static analyses for varying amounts of TNT. The blast effects in the supporting pier are determined using both static and dynamic analyses. Further research needs to be done in the dynamic analysis of the bridge system subjected to blast loads.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/227976
- Subject Headings
- Steel, Structural, Testing, Bridges, Design and construction, Structural dynamics
- Format
- Document (PDF)
- Title
- Development of an integrated computational tool for design and analysis of composite turbine blades under ocean current loading.
- Creator
- Zhou, Fang., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
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A computational tool has been developed by integrating National Renewable Energy Laboratory (NREL) codes, Sandia National Laboratories' NuMAD, and ANSYS to investigate a horizontal axis composite ocean current turbine. The study focused on the design, analysis, and life prediction of composite blade considering random ocean current, cyclic rotation, and hurricane-driven ocean current. A structural model for a horizontal axis FAU research OCT blade was developed. Following NREL codes were used...
Show moreA computational tool has been developed by integrating National Renewable Energy Laboratory (NREL) codes, Sandia National Laboratories' NuMAD, and ANSYS to investigate a horizontal axis composite ocean current turbine. The study focused on the design, analysis, and life prediction of composite blade considering random ocean current, cyclic rotation, and hurricane-driven ocean current. A structural model for a horizontal axis FAU research OCT blade was developed. Following NREL codes were used: PreCom, BModes, ModeShape, AeroDyn and FAST. PreComp was used to compute section properties of the OCT blade. BModes and ModeShape calculated the mode shapes of the blade. Hydrodynamic loading on the OCT blade was calculated by modifying the inputs to AeroDyn and FAST. These codes were then used to obtain the dynamic response of the blade, including blade tip displacement, normal force (FN) and tangential force (FT), flap and edge bending moment distribution with respect to blade rotation.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362582
- Subject Headings
- Structural dynamics, Fluid dynamics, Marine turbines, Mathematical models, Turbines, Blades, Design and construction
- Format
- Document (PDF)
- Title
- Protective effects of indomethacin and dexamethasone in a goat model with intrauterine balloon aortic valvuloplasty.
- Creator
- Zhou, Kaiyu, Wu, Gang, Li, Yifei, Zhao, Liang, Zhou, Rong, Zhu, Qi, Huang, Xupei, Mu, Dezhi, Hua, Yimin
- Date Issued
- 2012
- PURL
- http://purl.flvc.org/fau/fd/FAUIR000151
- Format
- Citation
