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The Calibration And Verification Of Simulation Models For Toll PlazasRusso, Christopher 01 January 2008 (has links)
A great deal of research has been conducted on Central Florida toll roads to better understand the characteristics of the tolling operation. In this thesis, the development and calibration of a toll plaza simulation models will be analyzed using two simulation programs varying mostly in their modeling theory. The two models utilized are, SHAKER, a deterministic queuing model for vehicles utilizing toll collection facilities, and VISSIM, a globally popular stochastic simulation software. The benefits of simulation models leads to the purpose of this thesis, which is to examine the effectiveness of two toll modeling programs that are similar in purpose but vary in approach and methodology. Both SHAKER and VISSIM toll plaza models have the potential to work as a tool that can estimate the maximum throughput and capacity of toll plazas. Major operational benefits resulting from developing these models are to simulate and evaluate how traffic conditions will change when demand increases, when and if queues increase when a lane is closed due to maintenance or construction, the impact of constructing additional lanes, or determining whether or not the best lane type configuration is currently implemented. To effectively calibrate any model available site data must be used to compare simulation results to for model validity. In an effort to correctly calibrate the SHAKER toll plaza tool and VISSIM model, an extensive field collection procedure was conducted at four Florida Turnpike operated toll facilities located in Central Florida. Each site differed from the others in terms of number of lanes, lane configuration, toll base fee, highway location, traffic demand, and vehicle percentage. The sites chosen for data collection were: the Lake Jesup Mainline Plaza along the Seminole Expressway (SR-417), the Beachline West Expressway Toll Plaza along the SR-528, the Daniel Webster Western Beltway Plaza along SR-429, and the Leesburg Toll Plaza along the Florida Turnpike Mainline SR-91. Upon completion of calibration of the two simulation models it is determined that each of the two software are successful in modeling toll plaza capacity and queuing. As expected, each simulation model does possess benefits over the other in terms of set up time, analysis reporting time, and practicality of results. The SHAKER model setup takes mere seconds in order to create a network and input vehicle, another few seconds to calibrate driving parameters, and roughly 10 additional seconds to report analysis. Conversely, setting up the VISSIM model, even for the most experienced user, can take several hours and the report analysis time can take several more hours as it is dependant on the number of required simulation runs and complexity of the network. VISSIM is most beneficial by the fact that its modeling allows for driver variability while SHAKER assumes equilibrium amongst lane choice and queuing. This creates a more realistic condition to observed traffic patterns. Even though differences are prevalent, it is important that in each simulation model the capacity is accurately simulated and each can be used to benefit operational situations related to toll plaza traffic conditions.
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Refining Genotypes and Phenotypes in KCNA2-Related Neurological DisordersDöring, Jan H., Schröter, Julian, Jüngling, Jerome, Biskup, Saskia, Klotz, Kerstin A., Bast, Thomas, Dietel, Tobias, Korenke, G. Christoph, Christoph, Sophie, Brennenstuhl, Heiko, Rubboli, Guido, Moller, Rikke S., Lesca, Gaetan, Chaix, Yves, Kölker, Stefan, Hoffmann, Georg F., Lemke, Johannes R., Syrbe, Steffen 06 February 2024 (has links)
Pathogenic variants in KCNA2, encoding for the voltage-gated potassium channel Kv1.2,
have been identified as the cause for an evolving spectrum of neurological disorders. Affected
individuals show early-onset developmental and epileptic encephalopathy, intellectual disability, and
movement disorders resulting from cerebellar dysfunction. In addition, individuals with a milder
course of epilepsy, complicated hereditary spastic paraplegia, and episodic ataxia have been reported.
By analyzing phenotypic, functional, and genetic data from published reports and novel cases,
we refine and further delineate phenotypic as well as functional subgroups of KCNA2-associated
disorders. Carriers of variants, leading to complex and mixed channel dysfunction that are associated
with a gain- and loss-of-potassium conductance, more often show early developmental abnormalities
and an earlier onset of epilepsy compared to individuals with variants resulting in loss- or gain-of-
function. We describe seven additional individuals harboring three known and the novel KCNA2
variants p.(Pro407Ala) and p.(Tyr417Cys). The location of variants reported here highlights the
importance of the proline(405)–valine(406)–proline(407) (PVP) motif in transmembrane domain S6 as
a mutational hotspot. A novel case of self-limited infantile seizures suggests a continuous clinical
spectrum of KCNA2-related disorders. Our study provides further insights into the clinical spectrum,
genotype–phenotype correlation, variability, and predicted functional impact of KCNA2 variants.
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A New Multiple Input Random Excitation Technique Utilizing Pneumatic CylindersSharma, Akhil 12 September 2016 (has links)
No description available.
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Influence des glycines du lien S4-S5 sur le couplage électromécanique des canaux ioniques dépendants du voltageBarreto, Sandra 03 1900 (has links)
Les canaux potassiques dépendants du voltage sont formés de quatre sous-unités, chacune possédant six segments transmembranaires (S1-S6) et une boucle (p-loop) qui se trouve entre le cinquième et le sixième segment au niveau du pore. Il est connu que le segment senseur du voltage (S1-S4) subit un mouvement lorsque le potentiel membranaire change. Pour ouvrir le canal, il est nécessaire de transférer l'énergie du senseur du voltage (généré par le mouvement des charges positives de S4) au pore. Le mécanisme exact de ce couplage électromécanique est encore sous étude. Un des points de liaison entre le senseur de voltage et le pore est le lien physique fait par le segment S4-S5 (S45L). Le but de cette étude est de déterminer l'influence de la flexibilité du segment S45L sur le processus de couplage. Dans le S45L, trois glycines sont distribuées dans des positions différentes. Elles sont responsables de la flexibilité des hélices-alpha. Ces glycines (mais pas leurs positions exactes) sont conservées pour tous les canaux potassiques dépendants de potentiel. En utilisant la technique de mutagènes dirigé, la glycine a été remplacée dans chacune de ces différentes positions par une alanine et dans une deuxième étape, par une proline (pour introduire un angle dans l'hélice). Pour étudier le comportement des canaux dans cette nouvelle conformation, on a appliqué la technique de « patch clamp » pour déterminer les effets lors de l'ouverture du pore (courant ionique). Avec le « cut-open oocyte voltage-clamp », nous avons étudié les effets sur le mouvement du senseur de voltage (courant “gating”) et la coordination temporelle avec l'ouverture du pore (courant ionique). Les données ont montré qu’en réduisant la flexibilité dans le S45L, il faut avoir plus d'énergie pour faire ouvrir le canal. Le changement pour une proline suggère que le mouvement du senseur est indépendant du pore pendant l'ouverture du canal. / Voltage-gated potassium channels are formed of four subunits, each one with six transmembrane segments (S1-S6) and a loop (p-loop) between S5 and S6 at the level of the pore. It is known that the voltage sensitive segment (S1-S4) undergoes a movement upon membrane potential changes. To open the channel, it is necessary to transfer the energy of the voltage sensor (generated by the displacement of the positive charges of S4) to the pore. The exact mechanism of this “electromechanical coupling” is still under investigation. The voltage sensor and pore are physically linked by the S4-S5 linker (S45L). The aim of this study is to determine the influence of S45L flexibility on the coupling process. In the S45L, three glycines are distributed at different positions and are responsible for the flexibility of the alpha-helix. These glycines (but not their exact position) are conserved within the potassium voltage-gated ion channels. The glycines were each replaced by an alanine using point mutagenesis. In a second step, a proline was introduced at the position in order to introduce a break in the helix. To study the behaviour of channels in this new conformation, we used the patch clamp technique to determine the effects during the pore opening (ionic current). With the cut-open voltage-clamp we determined the effects on voltage sensor movement (gating current) as well as the temporal correlation with the pore opening (ionic current). The data showed that when the flexibility of the S45L is reduced, the channel needs more energy to open. Exchange with proline suggests that the movement of the sensor is independent of pore opening.
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Aspergillus terreus isolamento, identifica??o e avalia??o da capacidade catal?tica na redu??o de cetonas pr?-quiraisEspeleta, Alexandre de Freitas 30 September 2014 (has links)
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Previous issue date: 2014-09-30 / The object of this inquiry is the isolation, the selection and the potential evaluation of a microorganism with biocatalytic activity in carrying out selective-stereo biorreduction of pro-chial ketones. In the research procedure, Fungi was isolated from soil samples contaminated with lead. Only one of the isolates fungi, identified as Aspergillus terreus, presented good catalytic activity in the reduction of acetophenone. The biomass was grown submerged in broth culture, inoculated with 1,1 x 103 (spores/mL of malt extract) and maintained at 30?C under orbital agitation. Morphological differences and catalytic activity were evaluated in function of the orbit of agitation during the growth process. The catalytic activity in terms of conversion of acetophenone and enantiomeric excess (S), ee_S, in 1-feniletanol, was determinate in conjunction with the growth curve of the fungus. The results were used to construct a graphic showing the variation of quality of the catalyst, according to age of biomass. Apart from acetophenone were tested o-Xacetophenone, p-Xacetophenone and m-Xacetophenone (X = methyl, methoxy, nitro, fluorine, bromine). For reaction with 24 hours growing cells (30?C; 150rpm/r = 50mm), the conversions were between 27% and 97% with ee_S between 41% and 83%. For reactions with cells in suspension in buffered medium (pH = 4.5 ? 6,5) was decrease in activity/selectivity at pH above 5.5. The kinetics of conversion was evaluated for biomasses with different ages and for various concentrations of acetophenone. An amount between 100mg and 200mg of biomass (dry mass) with 168 hours of culture can convert 100mg of acetophenone to 1(S)-feniletanou ee_S (91%) with 98% yield in 72 hours of reaction (93% at 48 hours). The development of this process described above, constitutes the body of this thesis. / O objetivo desta pesquisa ? o isolamento, a sele??o e a avalia??o de um microorganismo com atividade biocatalisadora na biorredu??o estereoseletiva de cetonas pro-quirais. No procedimento de investiga??o, fungos foram isolados de amostras de solo contaminadas com chumbo. Apenas um dos fungos isolados, identificado geneticamente como Aspergillus terreus, apresentou boa atividade catal?tica na redu??o de acetofenona. A biomassa foi cultivada submersa no caldo de cultura, inoculado com 1,1x103 (esporos/mL de extrato de malte) e mantido a 30? sob agita??o orbital. Diferen?as morfol?gicas e de atividade catal?tica foram avaliadas em fun??o da ?rbita de agita??o durante o crescimento. A atividade catal?tica, em termos de convers?o da acetofenona e do excesso enantiom?rico (S), ee_S, no 1-feniletanol, foi determinada em conjunto com a curva de crescimento do fungo. Os resultados foram usados para construir um gr?fico mostrando a varia??o da qualidade do catalisador em fun??o da idade da biomassa. Al?m de acetofenona, foram testadas o-Xacetofenona, p-Xacetofenona e m-Xacetofenona (X=metil, metoxi, nitro, fl?or, bromo). Para 24 horas de rea??o com c?lulas em crescimento (30?C; 150rpm/r = 50mm), as convers?es ficaram entre 94 e 100%, com ee_S ? 98% para acetofenona e para acetofenonas orta ou meta substitu?das. Com substituintes na posi??o para, a convers?o ficou entre 27% e 97%, com ee_S entre 41% e 83%. Para rea??es com c?lulas em suspens?o em meio tamponado (pH = 4,5 ? 6,5), houve queda na atividade/seletividade em pH acima de 5,5. A cin?tica de convers?o foi avaliada para biomassas com idades distintas e para v?rias concentra??es de acetofenona. Uma quantidade entre 100mg e 200mg de biomassa (massa seca) com 168 horas de cultura, pode converter 100mg de acetofenona a 1(S)-feniletanol (ee_S 91%), com 98% de rendimento em 72 horas de rea??o (93% em 48 horas). O desenvolvimento desse processo, acima descrito, constitui o corpo desta Tese.
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MYOSIN-XVA IS KEY MOLECULE IN ESTABLISHING THE ARCHITECTURE OF MECHANOSENSORY STEREOCILIA BUNDLES OF THE INNER EAR HAIR CELLSHadi, Shadan 01 January 2018 (has links)
Development of hair cell stereocilia bundles involves three stages: elongation, thickening, and supernumerary stereocilia retraction. Although Myo-XVa is known to be essential for stereocilia elongation, its role in retraction/thickening remains unknown. We quantified stereocilia numbers/diameters in shaker-2 mice (Myo15sh2) that have deficiencies in “long” and “short” isoforms of myosin-XVa, and in mice lacking only the “long” myosin-XVa isoform (Myo15ΔN). Our data showed that myosin-XVa is largely not involved in the developmental retraction of supernumerary stereocilia. In normal development, the diameters of the first (tallest)/second row stereocilia within a bundle are equal and grow simultaneously. The diameter of the third row stereocilia increases together with that of taller stereocilia until P1-2 and then either decreases almost two-fold in inner hair cells (IHCs) or stays the same in outer hair cells (OHCs), resulting in a prominent diameter gradation in IHCs and less prominent in OHCs. Sh2 mutation abolishes this gradation in IHCs/OHCs. Stereocilia of all rows grow in diameters nearly equally in Myo15sh2/sh2 IHCs and OHCs. Conversely, ΔN mutation does not affect normal stereocilia diameter gradation until ~P8. Therefore, myosin-XVa “short” isoform is essential for developmental thinning of third row stereocilia, which causes diameter gradation within a hair bundle.
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Influence des glycines du lien S4-S5 sur le couplage électromécanique des canaux ioniques dépendants du voltageBarreto, Sandra 03 1900 (has links)
Les canaux potassiques dépendants du voltage sont formés de quatre sous-unités, chacune possédant six segments transmembranaires (S1-S6) et une boucle (p-loop) qui se trouve entre le cinquième et le sixième segment au niveau du pore. Il est connu que le segment senseur du voltage (S1-S4) subit un mouvement lorsque le potentiel membranaire change. Pour ouvrir le canal, il est nécessaire de transférer l'énergie du senseur du voltage (généré par le mouvement des charges positives de S4) au pore. Le mécanisme exact de ce couplage électromécanique est encore sous étude. Un des points de liaison entre le senseur de voltage et le pore est le lien physique fait par le segment S4-S5 (S45L). Le but de cette étude est de déterminer l'influence de la flexibilité du segment S45L sur le processus de couplage. Dans le S45L, trois glycines sont distribuées dans des positions différentes. Elles sont responsables de la flexibilité des hélices-alpha. Ces glycines (mais pas leurs positions exactes) sont conservées pour tous les canaux potassiques dépendants de potentiel. En utilisant la technique de mutagènes dirigé, la glycine a été remplacée dans chacune de ces différentes positions par une alanine et dans une deuxième étape, par une proline (pour introduire un angle dans l'hélice). Pour étudier le comportement des canaux dans cette nouvelle conformation, on a appliqué la technique de « patch clamp » pour déterminer les effets lors de l'ouverture du pore (courant ionique). Avec le « cut-open oocyte voltage-clamp », nous avons étudié les effets sur le mouvement du senseur de voltage (courant “gating”) et la coordination temporelle avec l'ouverture du pore (courant ionique). Les données ont montré qu’en réduisant la flexibilité dans le S45L, il faut avoir plus d'énergie pour faire ouvrir le canal. Le changement pour une proline suggère que le mouvement du senseur est indépendant du pore pendant l'ouverture du canal. / Voltage-gated potassium channels are formed of four subunits, each one with six transmembrane segments (S1-S6) and a loop (p-loop) between S5 and S6 at the level of the pore. It is known that the voltage sensitive segment (S1-S4) undergoes a movement upon membrane potential changes. To open the channel, it is necessary to transfer the energy of the voltage sensor (generated by the displacement of the positive charges of S4) to the pore. The exact mechanism of this “electromechanical coupling” is still under investigation. The voltage sensor and pore are physically linked by the S4-S5 linker (S45L). The aim of this study is to determine the influence of S45L flexibility on the coupling process. In the S45L, three glycines are distributed at different positions and are responsible for the flexibility of the alpha-helix. These glycines (but not their exact position) are conserved within the potassium voltage-gated ion channels. The glycines were each replaced by an alanine using point mutagenesis. In a second step, a proline was introduced at the position in order to introduce a break in the helix. To study the behaviour of channels in this new conformation, we used the patch clamp technique to determine the effects during the pore opening (ionic current). With the cut-open voltage-clamp we determined the effects on voltage sensor movement (gating current) as well as the temporal correlation with the pore opening (ionic current). The data showed that when the flexibility of the S45L is reduced, the channel needs more energy to open. Exchange with proline suggests that the movement of the sensor is independent of pore opening.
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Conception parasismique robuste de bâtiments à base d'assemblages boulonnésSaranik, Mohammad 12 December 2011 (has links)
La procédure d’évaluation des performances des structures en génie civil soumis à des tremblements de terre implique le développement des modèles mathématiques et des procédures d’analyse dynamique non-linéaire pour estimer les réponses sismiques. Le comportement hystérétique des structures est connu pour être fortement dépendante du modèle de l’assemblage. Dans le cas de chargement cyclique, la plastification cyclique, le phénomène de fatigue oligocyclique et la détérioration du comportement dus à la dégradation de rigidité ont été jugées importantes. Cela éventuellement conduit à une grande incertitude dans les réponses d’une structure. Dans ce contexte, un modèle d’endommagement basé sur la fatigue hystérétique est développé pour évaluer la performance sismique des ossatures en acier avec des assemblages boulonnés à plaque d’extrémité. Le modèle développé est un modèle hystérétique dégradant basé sur l’indicateur de dommage par fatigue oligocyclique. Une étude expérimentale du comportement d’un assemblage boulonné à plaque d’extrémité est réalisée pour analyser les effets du comportement en fatigue oligocyclique et pour développer un modèle de prédiction de durée de vie. Les essais de fatigue ont été effectués en utilisant un pot vibrant. Les résultats des essais expérimentaux de fatigue seront utilisés pour déduire les paramètres de la fatigue qui sont nécessaires pour développer le modèle hystérétique de l’assemblage boulonné. L’analyse des dommages sismiques est l’un des problèmes les plus difficiles dans des structures grandes et complexes, particulièrement celles en ossature avec des assemblages boulonnés à plaque d’extrémité. L’existence de dommages structuraux dans une structure conduit à la modification des modes de vibration et les valeurs propres globaux sont généralement sensibles à l’ampleur des dégâts sismiques locaux dans des assemblages boulonnés. Dans ce travail, une analyse temporelle non-linéaire qui tient compte des modes et des fréquences non-linéaires a été proposée. Selon cette approche, les modes et les fréquences non-linéaires peuvent être déterminés par une procédure itérative qui repose sur la méthode de linéarisation équivalente. L’introduction de la notion des modes non-linéaires a permis d’étendre la méthode de synthèse modale linéaire aux cas non-linéaires afin d’obtenir la réponse dynamique des systèmes non-linéaires. Dans un autre contexte expérimental, cette thèse présente les résultats d’essais sur une table vibrante. L’objectif des essais expérimentaux est de comprendre le comportement inélastique des structures en acier soumis à des charges dynamiques. Par ailleurs, ces essais sont également destinés à étudier les changements dans les paramètres modaux dus au développement du comportement élasto-plastique et du dommage par fatigue oligocyclique des assemblages boulonnés. Une simulation numérique non-linéaire du système est effectuée sur la base du modèle développé et l’approche numérique proposée. Une comparaison des résultats obtenus à partir de l’analyse numérique et ceux des essais de table vibrante est présentée. Cependant, l’analyse des dommages pour les ossatures en acier sous excitations sismiques aléatoires exige l’application d’un algorithme adéquat. Un algorithme a été développé pour évaluer la performance sismique des ossatures en acier. En utilisant cet algorithme, l’influence de la fatigue oligocyclique sur le comportement des assemblages boulonnés à plaques d’extrémité peut être étudiée. / The performance assessment procedure of civil engineering structures subjected to earthquakes involves the development of mathematical models and nonlinear dynamic analysis procedures to estimate seismic responses. The hysteretic behavior of structures was known to be strongly dependent on the connection model. In the case of cyclic loading, cyclic hardening, low cycle fatigue phenomena and deterioration of the behavior due to stiffness degradation were found to be important. This eventually led to high uncertainty in the responses of system. In this context, a Fatigue Damage-Based Hysteretic model is developed to evaluate the seismic performance of steel moment-resisting frames with end-plate connections. The developed model is a degrading hysteretic model based on the low cycle fatigue damage index. An experimental study of the behavior of a end-plate bolted connection is performed for analyzing the effects of low cycle fatigue behavior and developing a model for predicting life of end-plate bolted connection. The fatigue tests were conducted using a shaker. The experimental fatigue results will be used to derive the fatigue parameters that will be used to develop the hysteretic model of the bolted connection. Analysis of seismic damage is one of the most challenging problems in large and complex structures, particularly those in steel moment-resisting frame with end-plate bolted connections. The existence of structural damage in an engineering structure leads to the modification of vibration modes and global eigenvalues are usually sensitive to the degree of local damage seismic in bolted connections. In this work, a nonlinear time history analysis which takes into account nonlinear modes and frequencies was adopted. According to this approach, the nonlinear modes and frequencies can be determined by an iterative procedure which based on the method of equivalent linearization. The introduction of the notation of nonlinear modes permits an extension of the method of linear modal synthesis to nonlinear cases in order to obtain the dynamic response of nonlinear systems. In another experimental context, this thesis presents the results from shaking table tests of a two-story steel frame with end-plate bolted connections. The aim of the experimental tests is to understand the inelastic behavior of steel frame structures subjected to dynamic loads. Moreover, the purpose of these tests is also to study the changes in modal parameters due to the development of elasto-plastic behavior and low cycle fatigue damage in steel frame connections. A nonlinear numerical simulation of the system is performed based on the developed model and the proposed numerical approach. A comparison of the results obtained from numerical analysis and those of shake table testing is presented. However, the damage analysis for steel frames under random seismic excitations requires the application of an adequate algorithm. An algorithm was developed to assess the seismic performance of steel frames with bolted connections. Using this algorithm, the influence of low cycle fatigue damage in the behavior of end plate bolted connections can be studied.
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Virtuální dvojče pro testbed Průmyslu 4.0 / Virtual twin for testbed Industry 4.0Husák, Michal January 2020 (has links)
The goal of my master‘s thesis is to create a digital twin of a testbed Barman. The Barman is a school model of autonomous mixed drinks production line that demonstrates the principles of Industry 4.0. In the theoretical part of the thesis, the choice of a suitable tool for virtualization is discussed. The Tecnomatix Process Simulate and the Mechatronic Concept Designer module integrated in the NX platform is compared. The practical part of the work is divided into two phases. The first phase was about looking for a way to integrate the robotic SCARA manipulator. The second phase was focused on the virtualization of the cell Shaker in the latter of the tools mentioned before. This work is designed as a guide for creating and verifying the concept of a digital twin.
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Development of a Closed-loop Resonant Fatigue Testing Methodology and Experimental Life Test of Aluminum AlloyAbdullah, A.B.M. 13 December 2010 (has links)
No description available.
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