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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

Radici teologiche della metafisica di Xavier Zubiri

Ambrosio, Valentina 20 January 2016 (has links)
Aquest treball planteja l'anàlisi de les possibles arrels teològiques del pensament metafísic del filòsof Xavier Zubiri. Al llarg del treball anirem investigant el sistema metafísic d'un pensador que representa la problemàtica de replantejar la filosofia i la teologia segons un marc originari, retornant a les dues disciplines el seu significat primari. I per aconseguir aquest objectiu, hem considerat necessari fer un recorregut en el pensament d'un gran autor i buscar en això les possibles arrels teològiques, a través del diàleg amb la tradició filosòfica. Després de l'estudi de l'obra Sobre l'essència, i de les preocupacions metafísiques aquí elaborades, ens proposem esbrinar les assercions teològiques, sobre la realitat divina, concebuda com extàtica efusió de l'àgape, categoria metafísica de la realitat divina i via d'accés per la deïficació de l'home, considerat essència oberta i constitutivament relligat. La tesi està dividida en tres parts. En la primera ens ocuparem del context històric en el qual s'ha desenvolupat el pensament del jove pensador, fins a la trobada amb Viktor Warnach i la superació de les doctrines modernistes. En la segona, la part més sistemàtica, centrarem la dissertació en Sobre l' essència, subratllant els passatges més significatius pel que es refereix a la presència de la teologia grega i paulina. En la tercera i última part, es tanca el cercle obert amb les primeres dues seccions, amb l'aportació dels textos teològics del filòsof, per complir un pas ulterior cap a l'aplicació directa de les qüestions teològiques a la metafísica de Zubiri. L'experiència religiosa i la intel·lectual formen un conjunt, concebut a la llum d'una nova interpretació biogràfica i a partir de la font conceptual de la Teologia paulina i de la Teologia del misteri. La metafísica de l'autor, segons la nostra recerca, no pot prescindir d'aquest fonamental context religiós. I és gràcies a aquest nou enfocament que la filosofia de Zubiri adquireix profunditat en la cerca de les qüestions últimes, en acord amb l'infatigable labor de la filosofia per aconseguir la veritat. / Este trabajo plantea el análisis de las posibles raíces teológicas del pensamiento metafísico del filosofo Xavier Zubiri. A lo largo del trabajo iremos investigando el sistema metafísico de un pensador que representa la problemática de replantear la filosofía y la teología según un marco originario, devolviendo a las dos disciplinas su significado primario. Y para lograr este objetivo, hemos considerado necesario hacer un recorrido en el pensamiento de un gran autor y buscar en ello las posibles raíces teológicas, a través del dialogo con la tradición filosófica. A través del estudio de la obra Sobre la esencia, y de las preocupaciones metafísicas ahí elaboradas, nos proponemos averiguar las aserciones teológicas, sobre la realidad divina, concebida como extática efusión del ágape, categoría metafísica de la realidad divina y vía de acceso para la deificación del hombre, considerado esencia abierta y constitutivamente religada. La tesis está dividida en tres partes. En la primera nos ocuparemos del contexto histórico en el cual se han desarrollado el pensamiento del joven pensador, hasta el encuentro con Viktor Warnach y la superación de las doctrinas modernistas. En la segunda, la parte más sistemática, centraremos la disertación en Sobre la esencia, subrayando los pasajes más significativos por lo que se refiere a la presencia de la teología griega y paulina. En la tercera y última parte, se cierra el círculo abierto con las primeras dos secciones, con el aporte de los textos teológicos del filósofo, para cumplir un paso ulterior hacia la aplicación directa de las cuestiones teológicas a la metafísica de Zubiri. La experiencia religiosa y la intelectual forman un conjunto, concebido a la luz de una nueva interpretación biográfica y a partir de la fuente conceptual de la Teología paulina e de la Teología del misterio. La metafísica del autor, según nuestra investigación, no puede prescindir de este fundamental contexto religioso. Y es gracias a este nuevo enfoque que la filosofía de Zubiri adquiere profundidad en la búsqueda de las cuestiones últimas, en acuerdo con el infatigable labor de la filosofía para alcanzar la verdad. / This work presents the analysis of possible theological roots of metaphysical thought of the philosopher Xavier Zubiri. Throughout the work we will be investigating the metaphysical system of a thinker who represents rethink the problem of philosophy and theology as an original framework, the two disciplines returning to its primary meaning. And to achieve this purpose, we have found it necessary to take a tour at the thought of a great philosopher and look at it possible theological roots, through dialogue with the philosophical tradition. Through the study of the work on the essence, and there elaborate metaphysical concerns, we intend to find out the theological assertions about the divine reality, conceived as ecstatic outpouring of agape, metaphysical category of divine reality and path for deification of man, considered open and constitutively religated essence. The thesis is divided into three parts. In the first we look at the historical context in which they have developed the thought of the young philosopher, to the meeting with Viktor Warnach and overcoming modernist doctrines. In the second, the systematic part, the dissertation will focus on the essence, highlighting the most significant passages so it refers to the presence of Greek and Pauline theology. In the third and final part, the circle opened with the first two sections, with the contribution of theological texts of the philosopher, to fulfill a further step towards the direct application of theological metaphysics of Zubiri issues is closed. The religious experience and intellectual form a set, designed in the light of a new biographical interpretation and from the conceptual source of Pauline theology and the theology of the mystery. The metaphysics of the author, according to our research, cannot do without this fundamental religious context. And it is thanks to this new approach to the philosophy of Zubiri acquires depth in search of the latest issues, according to the tireless work of philosophy to reach the truth.
232

Network processors and utilizing their features in a multicast design

Diler, Timur 03 1900 (has links)
Approved for public release, distribution is unlimited / In order to address the requirements of the rapidly growing Internet, network processors have emerged as the solution to the customization and performance needs of networking systems. An important component in a network is the router, which receives incoming packets and directs them to specific routes elsewhere in the system. Network processors and the associated software control the routers and switches and allow software designers to deploy new systems such as multicasting forwarder and firewalls quickly.This thesis introduces network processors and their features, focusing on the Intel IXP1200 network processor. A multicast design for the IXP1200 using microACE is proposed. This thesis presents an approach to building a multicasting forwarder using the IXP1200 network processor layer-3 forwarder microACE that carries out unicast routing. The design is based on the Intel Internet exchange architecture and its active computing element (ACE). The layer-3 unicast forwarder microACE is used as a basic starting point for the design. Some software modules, called micoblocks, are modified to create a multicast forwarder that is flexible and efficient. / Lieutenant Junior Grade, Turkish Navy
233

Avaliação da dureza e módulo de elasticidade da interface de união resina – dentina utilizando a técnica de nanoindentação / Assessment of hardness and elastic modulus of resin-dentin bonding area using the nanoindentation technique

Higashi, Cristian 28 February 2008 (has links)
Made available in DSpace on 2017-07-24T19:22:09Z (GMT). No. of bitstreams: 1 Cristian Higashi.pdf: 1616679 bytes, checksum: a243cd9970614325c2c06ab7c7f592d1 (MD5) Previous issue date: 2008-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to assess the hardness and elastic modulus of resin-dentin bonding area formed by an ethanol/water-based (Adper TM Single Bond 2 [SB]) and an acetone-based system (One Step Plus [OS]), under different moisture conditions and application methods. On 24 human molars, a flat superficial dentin surface was exposed by wet abrasion. Two coats of SB or OS adhesive were applied on either a dry (D) or rewetted surface (W), under active (AA) or inactive (IA) application. After polymerization of the adhesives (600 mW/cm2/20 s), composite build-ups were constructed incrementally and specimens were stored in water (24 h). They were cross-sectioned perpendicular to the resin-dentin interface to obtain slices of 1.5 mm thickness that were embedded and polished before the test. Nanoindentations were made on composite resin, adhesive system, hybrid layer and dentin regions. The results of hardness and elastic modulus (GPa) of adhesive system and hybrid layer were analyzed by a three-way ANOVA and Tukey’s multiple comparison tests (α=0.05). The mean and standard deviation of hardness and elastic modulus values of composite resin were (1.02 ± 0.07) and (14.94 ± 0.67) respectively. In dentin, the hardness was (0.69 ± 0.10) and the elastic modulus (17.94 ± 1.84). In the adhesive layer, the highest hardness (0.38 ± 0.06) and elastic modulus (6.93 ± 0.93) of SB were obtained in W group. In this same area, the elastic modulus of OS (5.91 ± 1.12) was lowest in AA group. In the hybrid layer, the hardness of both adhesive systems was highest in AA group, however statistically significant just for OS (0.51 ± 0.2). In D group the highest hardness (0.47 ± 0.24) and elastic modulus (10.98 ± 4.65) of hybrid layer were obtained with AA. It was concluded that the active application of both adhesives in dry dentin resulted in higher hardness and elastic modulus values in the hybrid layer and the moisture increased hardness and elastic modulus values of Adper TM Single Bond 2 in the adhesive layer. / O objetivo deste trabalho foi avaliar a dureza e módulo de elasticidade da interface de união resina-dentina formado por adesivos convencionais de 2 passos à base de água/etanol (Adper TM Single Bond 2 [SB]) e à base de acetona (One Step Plus [OS]), variando a umidade dentinária e forma de aplicação dos mesmos. 24 terceiros molares humanos foram lixados para a obtenção de uma superfície dentinária plana. Duas gotas do adesivo SB ou OS foram aplicadas de forma ativa (AA) ou inativa (AI) sobre uma dentina seca (S) ou reumedecida (U). Após a fotopolimerização dos adesivos (600 mW/cm2 / 20 s) os dentes foram restaurados incrementalmente e armazenados em água destilada por 24 h. Cortes perpendiculares à interface de união foram realizados para obtenção de fatias de aproximadamente 1,5 mm de espessura, que foram embutidas e polidas previamente ao teste. Nanoindentações foram realizadas nas regiões da resina composta, sistema adesivo, camada híbrida e dentina. Os valores de dureza e módulo de elasticidade (GPa) do sistema adesivo e camada híbrida foram submetidos a uma análise de variância de 3 fatores de medidas repetidas e ao teste de comparações múltiplas de Tukey (α=0,05). A média e desvio padrão dos valores de dureza e módulo de elasticidade da resina composta (GPa) foram (1,02 ± 0,07) e (14,94 ± 0,67), respectivamente. Na dentina, a dureza foi (0,69 ± 0,10) e o módulo de elasticidade (17,94 ± 1,84). Na camada de adesivo, os maiores valores de dureza (0,38 ± 0,06) e módulo de elasticidade (6,93 ± 0,93) do SB foram obtidos no grupo U. Nesta mesma região, o módulo de elasticidade do OS (5,91 ± 1,12) foi menor para o grupo AA. Na região da camada híbrida, a dureza de ambos os sistemas adesivos foi maior no grupo AA, porém significativamente somente para o OS (0,51 ± 0,2). No grupo S os maiores valores de dureza (0,47 ± 0,24) e módulo de elasticidade (10,98 ± 4,65) da camada híbrida foram obtidos com AA. Concluiu-se que a aplicação ativa de ambos os sistemas adesivos em substrato dentinário seco resultou nos maiores valores de dureza e módulo de elasticidade na região da camada híbrida e a umidade dentinária influenciou positivamente nos valores de dureza e módulo de elasticidade do sistema adesivo Adper TM Single Bond 2 na região da camada de adesivo.
234

Associação da 3-0-metilquercetina com beta-ciclodextrina : avaliação da complexação e penetração cutânea / 3-O-methylquercetin association with ß-cyclodextrin : evaluation of complexation and skin permeation

Schwingel, Liege Cassia January 2007 (has links)
No presente trabalho foi realizado o isolamento da 3-O-metilquercetina, a partir de produto seco do extrato de inflorescências de Achyrocline satureioides, e sua caracterização. Em etapa farmacotécnica, foi realizado o estudo da associação deste flavonóide com b-ciclodextrina, bem como testes preliminares de permeação cutânea das associações, incorporadas ou não em gel de hidroxipropilmetilcelulose. As técnicas espectroscópicas, infravermelho e ressonância magnética de hidrogênio, confirmaram a estrutura do flavonóide isolado. Para o doseamento da 3-Ometilquercetina, realizou-se a validação de metodologia analítica por cromatografia líquida de alta eficiência, obtendo-se linearidade, na faixa de concentração de 0,05 a 1,5 μg/mL, precisão e exatidão adequadas. A análise da associação da 3-Ometilquercetina com b-ciclodextrina por infravermelho, ressonância magnética de hidrogênio e a análise pelo método empírico de Mecânica Molecular (MM2) do software Chem3D Ultra (Versão 9.0, CambridgeSoft) indicam possível inclusão do anel B da 3-O-metilquercetina na cavidade da b-ciclodextrina, sendo a inserção do flavonóide pela borda das hidroxilas secundárias mais favorável do que pela borda das hidroxilas primárias. A b-ciclodextrina e o gel de hidroxipropilmetilcelulose promoveram a permeação do flavonóide através da pele. A realização de ensaios in vivo para a seleção da melhor formulação constitui-se na principal perspectiva de continuidade de investigação científica do tema. / 3-O-methylquercetin (3-OMQ) was isolated from spray dried powder of Achyrocline satureioides and characterized by IR and 1H NMR. The study of association of this flavonoid with b-cyclodextrin (bCD) was performed, as well as preliminary skin permeation tests of these associations, incorporated or not in hydroxypropyl methylcellulose (HPMC) hydrogel. A LC method for 3-OMQ assay was validated in the concentration range from 0.05 to 1.5 μg/mL, with suitable precision and accuracy. The complexation of 3-OMQ with bCD was analyzed by IR, 1H NMR and Molecular Mechanics (Chem3D Ultra 9.0, CambridgeSoft) and the results indicated the possible insertion of B ring of the flavonoid into the bCD cavity, being the insertion through the secondary OH rim more favorable than through the primary OH rim. bCD and HPMC promoted the permeation of the flavonoid through the skin. In vivo assay is required to select the appropriate formulation.
235

High Level Techniques for Leakage Power Estimation andOptimization in VLSI ASICs

Gopalakrishnan, Chandramouli 26 September 2003 (has links)
As technology scales down and CMOS circuits are powered by lower supply voltages, standby leakage current becomes significant. A behavioral level framework for the synthesis of data-paths with low leakage power is presented. There has been minimal work done on the behavioral synthesis of low leakage datapaths. We present a fast architectural simulator for leakage (FASL) to estimate the leakage power dissipated by a system described hierarchically in VHDL. FASL uses a leakage power model embedded into VHDL leafcells. These leafcells are characterized for leakage accurately using HSPICE. We present results which show that FASL measures leakage power significantly faster than HSPICE, with less than a 5% loss in accuracy, compared to HSPICE. We present a comprehensive framework for synthesizing low leakage power data-paths using a parameterized Multi-threshold CMOS (MTCMOS) component library. The component library has been characterized for leakage power and delay as a function of sleep transistor width. We propose four techniques for minimization of leakage power during behavioral synthesis: (1) leakage power management using MTCMOS modules; (2) an allocation and binding algorithm for low leakage based on clique partitioning; (3) selective binding to MTCMOS technology, allowing the designer to have control over the area overhead; and (4) a performance recovery technique based on multi-cycling and introduction of slack, to alleviate the loss in performance attributed to the introduction of MTCMOS modules in the data-path. Finally, we propose two iterative search based techniques, based on Tabu search, to synthesize low leakage data-paths. The first technique searches for low leakage scheduling options. The second technique simultaneously searches for a low leakage schedule and binding. It is shown that the latter technique of unified search is more robust. The quality of results generated bytabu-based technique are superior to those generated by simulated annealing (SA) search technique.
236

Etude de Resolution Search pour la programmation linéaire en variables binaires

Boussier, Sylvain 27 November 2008 (has links) (PDF)
Dans cette thèse, nous nous intéressons à la résolution exacte de programmes linéaires en variables binaires. L'ensemble de nos travaux s'articule autour de l'étude de Resolution search (Chvátal (1997)) pour la résolution du problème du sac à dos multidimensionnel en 0-1. Dans un premier temps, nous proposons un algorithme d'énumération implicite centré sur une analyse des coûts réduits à l'optimum de la relaxation continue ainsi que sur une décomposition de l'espace de recherche en hyperplans. Nous proposons une stratégie de branchement originale visant à élaguer au plus tôt l'arbre de recherche. Cette stratégie est efficace pour résoudre des instances jugées difficiles mais rend l'algorithme dépendant de la connaissance d'une bonne solution de départ. Dans un deuxième temps, nous proposons une méthode de résolution plus autonome combinant Resolution search avec une énumération implicite inspirée du premier algorithme. Cette coopération permet d'obtenir rapidement de bonnes solutions et prouve les optimums d'instances de plus grande taille. Finalement, nous présentons une application de Resolution Search à la résolution d'un problème de planification dans le domaine des télécommunications.
237

Multi-period optimization of pavement management systems

Yoo, Jaewook 30 September 2004 (has links)
The purpose of this research is to develop a model and solution methodology for selecting and scheduling timely and cost-effective maintenance, rehabilitation, and reconstruction activities (M & R) for each pavement section in a highway network and allocating the funding levels through a finite multi-period horizon within the constraints imposed by budget availability in each period, frequency availability of activities, and specified minimum pavement quality requirements. M & R is defined as a chronological sequence of reconstruction, rehabilitation, and major/minor maintenance, including a "do nothing" activity. A procedure is developed for selecting an M & R activity for each pavement section in each period of a specified extended planning horizon. Each activity in the sequence consumes a known amount of capital and generates a known amount of effectiveness measured in pavement quality. The effectiveness of an activity is the expected value of the overall gains in pavement quality rating due to the activity performed on a highway network over an analysis period. It is assumed that the unused portion of the budget for one period can be carried over to subsequent periods. Dynamic Programming (DP) and Branch-and-Bound (B-and-B) approaches are combined to produce a hybrid algorithm for solving the problem under consideratioin. The algorithm is essentially a DP approach in the sense that the problem is divided into smaller subproblems corresponding to each single period problem. However, the idea of fathoming partial solutions that could not lead to an optimal solution is incorporated within the algorithm to reduce storage and computational requirements in the DP frame using the B-and-B approach. The imbedded-state approach is used to reduce a multi-dimensional DP to a one-dimensional DP. For bounding at each stage, the problem is relaxed in a Lagrangean fashion so that it separates into longest-path network model subproblems. The values of the Lagrangean multipliers are found by a subgradient optimization method, while the Ford-Bellman network algorithm is employed at each iteration of the subgradient optimization procedure to solve the longest-path network problem as well as to obtain an improved lower and upper bound. If the gap between lower and upper bound is sufficiently small, then we may choose to accept the best known solutions as being sufficiently close to optimal and terminate the algorithm rather than continue to the final stage.
238

Bewertung individueller Voraussetzungen zur Bewältigung wechselnder Arbeitsanforderungen anhand psychologischer und neuropsychologischer Parameter / Evaluation of individual conditions for the accomplishment of changing work requirements on the basis psychological and neurophysiological parameters

May, Jana January 2004 (has links)
Ziel der vorliegenden Arbeit war es, mittels des Aufgabenwechselparadigmas, kognitive Prozesse nicht nur anhand von traditionellen Leistungsparametern, sondern zusätzlich durch elektro-physiologische Parameter zu untersuchen. Parameter ereigniskorrelierter Hirnpotentiale (EKP) wurden ebenfalls zur Einschätzung von altersbedingten Änderungen bei der Ausführung von Reaktionszeitaufgaben herangezogen.<br> Nach Rubinstein et al. (2001) setzt sich die Reaktionszeit aus der Dauer seriell angeordneter Verarbeitungsstufen zusammen. Im Stufenmodell der exekutiven Kontrolle von Rubinstein et al. (2001) sind Prozesse der ausführenden Kontrolle nur an Wechseltrials beteiligt und können getrennt von den Aufgabenprozessen ablaufen. Mittels der Informationen zu den Reaktionszeiten ist es jedoch nicht möglich zu klären, auf welche kognitiven Verarbeitungsprozesse Reaktionszeitunterschiede unter den jeweiligen experimentellen Bedingungen zurückzuführen sind. Zur Analyse der kognitiven Prozesse wurden in dieser Untersuchung die CNV und P300 herangezogen. Es wurden zwei Altersgruppen (20-30 Jährige und 49-61 Jährige) untersucht. Den Probanden wurden Ziffern präsentiert, die entweder nach dem numerischen Wert oder der Schriftgröße mit dem Hinweisreiz, der Zahl 5, verglichen werden sollten. Die Stimuli wurden nach dem Alternating-Runs-Paradigma dargeboten (Rogers und Monsell, 1995).<br> Erwartungsgemäß gab es Reaktionszeitunterschiede zwischen alt und jung mit längeren Reaktionszeiten für die älteren Probanden. Altersunterschiede in den Fehlerraten ließen sich nicht nachweisen. Möglicherweise erfolgte die Reaktionsauswahl bei den Älteren überlegter aus als bei den Jüngeren. Dies spiegelte sich in längeren aber fehlerfreien Reaktionen wider. Vermutlich bereiteten jedoch alle Probanden in dem Intervall zwischen Cue und Stimulus das jeweilige Aufgabenset komplett vor. Das könnte auch erklären, warum es bei einem Aufgabenwechsel nicht zu einem Anstieg der Reaktionszeit und der Fehlerrate kam. Entgegen der Erwartung zeigten sich keine Wechselkosten. Teilweise wurden inverse Wechselkosten nachgewiesen. In Bezug auf die Wechselkosten konnte das Stufenmodell der exekutiven Kontrolle (Rubinstein et al., 2001) nicht bestätigt werden. Der explizite Hinweisreiz scheint allerdings Einfluss auf die Wechselkosten zu haben. Verschiedene Erklärungsansätze werden diskutiert.<br> Die Contingent Negative Variation ist wie erwartet vor einem Aufgabenwechsel größer als vor einer Aufgabenwiederholung. Durch den Hinweisreiz ist eine erhöhte Kapazität vorhanden. Entsprechend den Ergebnissen der CNV kann davon ausgegangen werden, dass ältere Erwachsene stärker von der Vorinformation zu profitieren scheinen als jüngere Erwachsene. Die älteren Erwachsenen beginnen im Gegensatz zu den jüngeren Erwachsenen offenbar eher mit der Vorbereitung. Zeitdruck und Aufgabenwechsel lösen eine stärkere P300 aus. Demzufolge scheinen Zeitdruck und Aufgabenwechsel einen erhöhten Kapazitätsbedarf zu erfordern. Im Sinne des Stufenmodells der exekutiven Kontrolle von Rubinstein et al. (2001) führt die Zielverschiebung bei einem Aufgabenwechsel zu einer größeren P300. Die Resultate der hier dargestellten Untersuchungen verdeutlichen, dass ältere Erwachsene einen höheren zeitlichen Aufwand in den Stufen der einzelnen exekutiven Prozesse benötigen. Dies spricht für die Hypothese der selektiven Verlangsamung. Ältere kompensieren dies durch einen höheren Aufwand in der Vorbereitung, was auf elektrokortikaler Ebene nachweisbar ist, sind aber nicht in der Lage, dies in den Reaktionszeiten umzusetzen.<br> Die Ergebnisse dieser Untersuchung unterstützen die vereinfachte Annahme von Rubinstein et al. (2001), nach dem die Teilprozesse der Reaktionszeit seriell verarbeitet werden können. Die Resultate lassen allerdings den Schluss zu, dass die Wechselkosten im Hinblick auf die Reaktionszeiten nicht der geeignete Parameter für die Messung der exekutiven Kontrolle sind.<br> Die vorgeschlagene Modifikation des Modells von Rubinstein et al. (2001) in der Vorbereitung auf eine Aufgabe gilt es in weiteren Untersuchungen zu bestätigen und die Möglichkeit der Anwendung auf alle Aspekte der exekutiven Kontrollprozesse zu prüfen. / The aim of this study was it to examine cognitive processes not only on the basis achievement parameters by means of the alternating runs paradigm, but additionally by electricalphysiological parameters. Parameters of event-correlated brain potentials (EKP) were also used to estimate age-related changes in tasks of response time.<br> According to Rubinstein et al. (2001) the response time consists of the duration of serially arranged processing levels. In Rubinstein's et al. (2001) stage model of the executive control processes of implementing control are involved only in switch trials and can run separately from the task processes. The information from response times do not aloud to define what cognitive processing processes are responsible for response time differences in respective to the experimental conditions. In this study the contingent negative variation (CNV) and P300 were used for the analysis of the cognitive processes.<br> Two age groups (20 to 30, and 49 to 61 years old) were included in the study. Numbers were presented, which should be compared to the cue number 5 either to the numeric value or character size. The stimuli were represented after the alternating runs paradigm (Rogers & Monsell, 1995).<br> As expected there were response time differences between old and young subjects with longer response times for the older ones. Age differences in the error rates could not be proven. It is possible that the reaction selection in older ones took place with more consideration than in the younger ones. This is reflected in longer but error free reactions. Probably all subjects prepared in the interval the respective task set between cue and stimulus completely. This could also explain, why with a task switching no rise of the response time and the error rate was noticed. Against expectation no switch costs showed up. Inverse switch costs were partly proven. Regarding the switch costs the stage model of the executive control (Rubinstein et al., 2001) could not be confirmed. The explicit cue however seems to have influence on the switch costs. Different explanations are discussed.<br> The contingent negative variation is higher before a task switching than before a repetition of task. By the cue an increased capacity is presented. According to the results of the CNV it can be assumed that older adults seem to profit more strongly than younger adults from the advance information. Obviously the older adults begin earlier with the preparation than the younger ones. Time pressure and task switching release a stronger P300. Therefore time pressure and task switching seem to require an increased capacity need. According to the stage model of the executive control (Rubinstein et al., (2001) the goal shift with goes along with the task switching leads to a higher P300.<br> The results of the study represented here clarify, that older adults need a more time in the stages of the individual executives of processes. This underlines the hypothesis of the selective slowing down. Older ones compensate this by more effort to preparation, which can be proven on the electrocortical level. The are not able to show this in the the response times, though. The results of this study support the simplified acceptance of Rubinstein et al. (2001), after which the subprocesses of the response time can be processed serially.<br> The results permit the conclusion that the switch costs regarding the response times are not the adaquate parameter for the measurement of the executive control.<br> The suggested modification of the model of Rubinstein et al. (2001) in the preparation for a task it applies to be confirmed in further investigations and the possibility of application to all aspects of the executives has to be tested.
239

The Guided Wave Inspection of Buried Pipe

Yeh, Chan-Chia 02 September 2012 (has links)
Abstract In a petrochemical plant, to exert economic efficiency and spacing convenience for transporting fluid or gas, the pipelines used in the plant are often buried along the road. The buried pipelines are usually wrapped in the soil that only the guided wave method is a convenient technique to perform the nondestructive testing for the pipelines. However, the viscosity of soil causes the attenuation of the guided wave during the test, the accuracy and the detection distance will then be affected. Thus, the objectives of this thesis are to study the characteristics, such as the detection distance and the refraction signal, of the T(0,1) guided wave when propagating along pipelines wrapped in the soil at different depths. The thesis would be divided into two parts: experiment and numerical simulation. Four different depths, 0.5, 1.0, 1.5 and 2.0 m, are used in the experiment to evaluate the characteristics of reflected signals and its attenuation. Wavelet transform, which would enhance the capability of distinguishing guided wave defect, is used to improve the attenuation of defected refraction signal caused by soil. In the numerical simulation, this research applies the transient simulation by finite element method to analyze the wave propagation behavior of T(0,1) mode guided wave of buried pipeline, which is incorporated with Two-dimensional Fourier transform for modal identification. The result of experiment shows that the attenuation of the guided wave is caused by the leakage and the viscosity of the soil. The decay rate is proportional to the depth and due to the viscosity of the soil is proportional to the excitation frequency. This phenomenon is more obvious when the pipeline is buried deeper. The reflected signal amplitude of each characteristic would decrease along with the increasing soil depth, but the overall trends did not changed. The result of wavelet transform shows that the capability of distinguishing of the guided wave detection defect of buried pipeline, which attenuation of refraction signal caused by soil would be improved. The result of the numerical simulation indicates that the T(0,1) mode would not cause mode conversion and dispersion due to its propagation through the buried pipeline with different depths of soil. The soil caused leakage of the T(0,1) mode in the form of shear waves. The attenuation rate of guided wave and its detection distance in the study could be the reference of site selection for detection and defect refraction signal determination, which could effectively raise the efficiency of on-site detection.
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Environmental And Individual Resources, Perception Of The Event, Cognitive Processing And Coping As Factors Leading To Posttraumatic Growth Among The Survivor Of Myocardial Infarction Patients And Their Spouses

Senol- Durak, Emre 01 June 2007 (has links) (PDF)
Posttraumatic Growth (PTG), known as antithesis of Post Traumatic Stress Disorder (PTSD) (Tedeschi, Park, &amp / Calhoun, 1998, p.3), has been highlighted in the literature as a positive outcome of the trauma.In the literature, environmental resources (e.g., social and familial support), individual resources (e.g., personality traits, socio-demographic variables), perception of the event (e.g., type of trauma, duration of trauma), cognitive processing (e.g. impact of event, religious participation), and coping (e.g. problem focused coping, emotion focused coping) were found as possible factors on the development of PTG. In the present study, a model to predict PTG in the patients suffering from myocardial infarction (MI / heart attack) and their spouses was tested on the basis of environmental and personal resources, the perception of the event and cognitive processing as latent variables. The model, developed by Schaefer and Moos (1998), was empirically analyzed for the first time with patients suffered from myocardial infarction and their spouses by structural equation model (SEM) using AMOS program. MI patients getting the treatment in various hospitals in the city of Bolu (N=151) and their spouses (N=137) completed the measures in 1.5-2 hours sessions. The analysis of the model with the MI patients&amp / #8217 / data revealed that both environmental resources and individual resources demonstrated indirect effects on PTG via the effect of the perception of the event, cognitive processing and coping. On the other hand, the analysis of the model for the spouses revealed that individual resources demonstrated indirect effects on PTG through the effect of the perception of the event, cognitive processing and coping while environmental resources did not show significant indirect effects on PTG.The findings were discussed in the context of recent theoretical models of PTG, shortcomings of the current study, clinical implications, and suggestions for future research.

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