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Influences of Object-Based Selection on the Relation Between Attention and Visual Temporal ResolutionNicol, Jeffrey R. 09 1900 (has links)
Attended objects are perceived differently than unattended objects. Spatial attention is consistently associated with an enhancement in spatial resolution. However, the relation between spatial attention and temporal resolution is not as straightforward. Some studies have shown that attention enhances temporal resolution, and others have shown that attention degrades temporal resolution. The motivation of the present work was to investigate the source of this discrepancy. In particular, the research herein examines the
hypothesis that attention degrades temporal resolution when the target stimuli are easily integrated (i.e., according to the Gestalt principles of grouping), and that attention enhances temporal resolution when the targets are easy to perceptually segregate. Temporal resolution was assessed by the mean just noticeable difference (the minimum temporal interval in milliseconds required by observers to perform the task at 75%
accuracy) in a visual temporal order judgment (TOJ) task. Trials involved the
presentation of two targets, at randomly varying stimulus onset asynchronies, and observers reported which one they perceived first. The primary research questions concerned the effect of perceptual grouping on temporal resolution, and the influence of attention on that relation. Grouping processes were manipulated using a variety of Gestalt principles and attention was investigated under conditions of automatically-and voluntarily-driven orienting. Three main findings emerged: temporal resolution is worse
for grouped than ungrouped targets; attention modulates the effect of grouping on temporal resolution on a continuum - strong grouping effects produce large impairments on temporal resolution, and weaker grouping effects produce smaller impairments; and automatic and voluntary spatial orienting affect the relation between grouping and temporal resolution differently - automatic orienting augments the relation, while
voluntary orienting does not. I conclude that the discrepant findings in the previous research are due to object-based factors pertaining to the target stimuli and propose an object-based theory of temporal perception. / Thesis / Doctor of Philosophy (PhD)
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Effect of aging on measures of visual attention using dual tasks and visual searchBabu, Raiju January 2010 (has links)
In Canada, as baby boomers age, there will be an increase in the percentage of seniors within the general population (Statistics Canada, 2006). Seniors often have difficulty in performing certain everyday tasks and have greater risk of having health issues. As such, it becomes increasingly important to understand factors that pose difficulty for this group of people. As people get older, many visual functions such as visual acuity, contrast sensitivity, and glare are known to deteriorate (Haegerstrom-Portnoy, 2005). However, when considering activities that aid mobility such as driving and walking, vision related variables are not the only ones that create difficulty for older individuals. A sensory variable such as attention, in conjunction with vision, has been shown in previous studies to be a good predictor of difficulties encountered by the elderly (McGwin, Owsley, & Ball, 1998; Owsley, McGwin, Sloane, Stalvey, & Wells, 2001). Moreover, inattention and distraction seem to be common causes of automobile accidents as well as falls. The work load imposed on the working memory can impact distractibility and inattention.
In mobility related activities such as driving and walking, individuals perceive objects that are increasing in size. Experiments were designed to investigate the factors that affect the perception of targets that are enlarging in size. Size matching of expanding targets to a previously presented static target, was investigated in a group of younger participants with normal vision using central or peripheral vision. The results show that size estimates differ depending on whether the target appears in the central visual field or in the periphery. The participants respond faster to targets that appear in the periphery compared to those in the centre/midline.
In the subsequent set of experiments we compared the performance of younger and older participants using a dual task paradigm where individuals had to perform two tasks concurrently, one of which was to match the size of an enlarging target. Attention was modulated in the dual tasks by varying the difficulty of the secondary task. It has been found that older individuals have difficulty processing multiple visual tasks or performing multiple tasks in general (Pashler, 1994a, 1994b, 1998; Verhaeghen et al., 2003). Compared to younger individuals, older individuals were found to have greater performance difficulty in the highly demanding dual tasks. These results are compared to those observed in studies of psychological refractory period effects. The differences between the young and older individuals are discussed with respect to limited capacity and bottle neck models of attention. Furthermore, eye movement measures in the dual tasks seem to provide evidence of difficulty in task switching for the older observers.
The thesis also investigated the functional field of view of younger and older individuals. By assessing the functional field of view (FFOV) using a method employed earlier by Coeckelbergh et al., (2004a), significant overall age related differences were found. Multiple characteristics of what might affect the FFOV as measured by the attended field of view (AFOV) were also investigated (e.g., impact of a pop out distracter and divided attention). It was found that differences between the two age groups occurred in all conditions. The presence of irrelevant distracters had a greater impact on the older individuals compared to the younger group, whereas divided attention or the presence of the pop out distracter did not affect either age group. Attention processing seemed to be similar for both the younger and older individuals and, therefore, the differences between the age groups appear to be at a quantitative level rather than a qualitative level.
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Effect of aging on measures of visual attention using dual tasks and visual searchBabu, Raiju January 2010 (has links)
In Canada, as baby boomers age, there will be an increase in the percentage of seniors within the general population (Statistics Canada, 2006). Seniors often have difficulty in performing certain everyday tasks and have greater risk of having health issues. As such, it becomes increasingly important to understand factors that pose difficulty for this group of people. As people get older, many visual functions such as visual acuity, contrast sensitivity, and glare are known to deteriorate (Haegerstrom-Portnoy, 2005). However, when considering activities that aid mobility such as driving and walking, vision related variables are not the only ones that create difficulty for older individuals. A sensory variable such as attention, in conjunction with vision, has been shown in previous studies to be a good predictor of difficulties encountered by the elderly (McGwin, Owsley, & Ball, 1998; Owsley, McGwin, Sloane, Stalvey, & Wells, 2001). Moreover, inattention and distraction seem to be common causes of automobile accidents as well as falls. The work load imposed on the working memory can impact distractibility and inattention.
In mobility related activities such as driving and walking, individuals perceive objects that are increasing in size. Experiments were designed to investigate the factors that affect the perception of targets that are enlarging in size. Size matching of expanding targets to a previously presented static target, was investigated in a group of younger participants with normal vision using central or peripheral vision. The results show that size estimates differ depending on whether the target appears in the central visual field or in the periphery. The participants respond faster to targets that appear in the periphery compared to those in the centre/midline.
In the subsequent set of experiments we compared the performance of younger and older participants using a dual task paradigm where individuals had to perform two tasks concurrently, one of which was to match the size of an enlarging target. Attention was modulated in the dual tasks by varying the difficulty of the secondary task. It has been found that older individuals have difficulty processing multiple visual tasks or performing multiple tasks in general (Pashler, 1994a, 1994b, 1998; Verhaeghen et al., 2003). Compared to younger individuals, older individuals were found to have greater performance difficulty in the highly demanding dual tasks. These results are compared to those observed in studies of psychological refractory period effects. The differences between the young and older individuals are discussed with respect to limited capacity and bottle neck models of attention. Furthermore, eye movement measures in the dual tasks seem to provide evidence of difficulty in task switching for the older observers.
The thesis also investigated the functional field of view of younger and older individuals. By assessing the functional field of view (FFOV) using a method employed earlier by Coeckelbergh et al., (2004a), significant overall age related differences were found. Multiple characteristics of what might affect the FFOV as measured by the attended field of view (AFOV) were also investigated (e.g., impact of a pop out distracter and divided attention). It was found that differences between the two age groups occurred in all conditions. The presence of irrelevant distracters had a greater impact on the older individuals compared to the younger group, whereas divided attention or the presence of the pop out distracter did not affect either age group. Attention processing seemed to be similar for both the younger and older individuals and, therefore, the differences between the age groups appear to be at a quantitative level rather than a qualitative level.
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CRAbCVE- Uma arquitetura para viabilização de CVEs através da Internet / CRAbCVE- An Architecture for CVEs through the InternetGomes, George Allan Menezes January 2005 (has links)
GOMES, George Allan Menezes. CRAbCVE- Uma arquitetura para viabilização de CVEs através da Internet. 2005. 184 f. Dissertação (Mestrado em ciência da computação)- Universidade Federal do Ceará, Fortaleza-CE, 2005. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-11T16:25:59Z
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Previous issue date: 2005 / Although the complexities of many tasks encountered in modern societies require the join effort of groups of people in order to be accomplished, cooperative work is still a difficult job. Usually the difficulties arise due to lack of appropriate coordination, poor definition of the context in which the activities are to be performed individually or in group; thus, generating redundancies, inconsistencies and contradictions within the workgroup. In order to overcome these problems, a new field of research, called Computer Supported Cooperative Work (CSCW), was created to seek means of properly supporting work groups. Despite the favorable results achieved by CSCW, thus far, tools that provide a high level of interaction among the group members and the leaders of sub-groups are still not satisfactory. The use of virtual reality within cooperative systems allows the interactions among participants to be highly spontaneous, because, in virtual environments, communication by means of image, text and audio is possible. The Collaborative Virtual Environments (CVEs), which employ shared virtual reality technology, have proved to possess great potential for collaborative work. Therefore, collaborative virtual environments have been developed taking into consideration the results obtained by CSCW research. Nonetheless, developing CVEs is complicated, since they demand a great deal of resources, and need to incorporate concepts and recommendations from several research fields, such as Virtual Reality (VR), Computer Supported Cooperative Work and l Distributed Computing. The main objective of this dissertation is to design a generic architecture (CRAbCVE) for allowing distribution of several collaborative virtual environments within a network of servers on the Internet. This architecture defines specialized components, capable of distributing the processing that takes place in the CVE, thus obtaining a great computational power at low costs. Another important objective is the specification of a Model of Authorship in CVEs (MAC) for helping to integrate the CRAbCVE architecture into the framework of collaborative work. All models proposed herein have been incorporated into a prototype system and a simple case study has been analyzed. / A complexidade das tarefas do mundo atual requer cada vez mais a cooperação das pessoas para sua execução. Entretanto cooperar não é uma tarefa fácil, e, muitas vezes, por falta de coordenação adequada ou por uma definição pobre do contexto em que as atividades dos participantes individualmente ou do grupo serão realizadas, são geradas redundâncias, inconsistências e contradições dentro do trabalho em grupo. Para evitar esses problemas, a área de CSCW (Computer Supported Cooperative Work) vem buscando meios de suportar adequadamente o trabalho em equipe. Apesar dos bons resultados alcançados pela área de CSCW, o principal obstáculo enfrentado pelos seus desenvolvedores é fornecer interatividade a suas aplicações. O uso de realidade virtual em sistemas cooperativos permite aos participantes interagirem com o mais alto grau de naturalidade, pois através do ambiente virtual é possível a comunicação por meio de imagem, texto e áudio. Os CVEs (Collaborative Virtual Environments) fazem uso da tecnologia de realidade virtual distribuída e apresentam grande potencial para o suporte ao trabalho colaborativo. Por conseguinte, esses ambientes virtuais colaborativos têm sido desenvolvidos, levando em consideração os resultados obtidos na área de CSCW. Entretanto, desenvolver CVEs é uma tarefa complicada, pois eles são grandes consumidores de recursos, e precisam incorporar conceitos e recomendações de várias áreas de pesquisa, como a de Realidade Virtual (RV), a de Trabalho Colaborativo Assistido por Computador (CSCW) e a de Sistemas Computacionais Distribuídos. O principal objetivo dessa dissertação é a definição de uma arquitetura de uso genérico, a CRAbCVE, projetada para viabilizar vários Ambientes virtuais colaborativos (CVEs) distribuídos em uma rede de servidores na Internet. Essa arquitetura define componentes especializados, capazes de distribuir, através da Internet, o processamento de todo o CVE; obtendo-se, assim, um grande poder computacional a um baixo custo. Outro importante objetivo é a definição do modelo MAC (Modelo de Autoria em CVEs), que visa auxiliar o emprego da arquitetura CRAbCVE no trabalho colaborativo. Os modelos propostos foram incorporados em um sistema protótipo e um estudo de caso simples foi analisado.
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Developing decision support systems for last mile transportation problemsPaidi, Vijay January 2019 (has links)
Last mile transportation is the most problematic phase of transportation needing additional research and effort. Longer waits or search times, lack of navigational directions and real-time information are some of the common problems associated with last mile transportation. Inefficient last mile transportation has an impact on the environment, fuel consumption, user satisfaction and business opportunities. Last mile problems exist in several transportation domains, such as: the landing of airplanes, docking of ships, parking of vehicles, attended home deliveries, etc. While there are dedicated inter-connected decision support systems available for ships and aircraft, similar systems are not widely utilized in parking or attended handover domains. Therefore, the scope of this thesis covers last mile transportation problems in parking and attended handover domains. One problem area for parking and attended handovers is due to lack of real-time information to the driver or consumer. The second problem area is dynamic scheduling where the handover vehicle must traverse additional distance to multiple handover locations due to lack of optimized routes. Similarly, during parking, lack of navigational directions to an empty parking space can lead to increased fuel consumption and CO2 emissions. Therefore, aim of this thesis is to design and develop decision support systems for last mile transportation problems by holistically addressing real time customer communication and dynamic scheduling problem areas. The problem areas discussed in this thesis consists of persistent issues even though they were widely discussed in the literature. In order to investigate the problem areas, microdata analysis approach was implemented in the thesis. The phases involved in Microdata analysis are: data collection, data processing, data storage, data analysis and decision-making. Other similar research domains, such as: computer science or statistics also involve phases such as data collection, processing, storage and analysis. These research domains also work in the fields of decision support systems or knowledge creation. However, knowledge creation or decision support systems is not a mandatory phase in these research domains, unlike Microdata analysis. Three papers are presented in this thesis, with two papers focusing on parking domains, while the third paper focuses on attended handover domains. The first paper identifies available smart parking tools, applications and discusses their uses and drawbacks in relation to open parking lots. The usage of cameras in identifying parking occupancy was recognized as one of the suitable tools in this paper. The second paper uses a thermal camera to collect the parking lot data, while deep learning methodologies were used to identify parking occupancy detection. Multiple deep learning networks were evaluated for identifying parking spaces and one method was considered suitable for acquiring real time parking occupancy. The acquired parking occupancy information can be communicated to the user to address real-time customer communication problems. However, the decision support system (DSS) to communicate parking occupancy information still needs to be developed. The third paper focuses on the attended handovers domain where a decision support system was reported which addresses real-time customer communication and dynamic scheduling problems holistically. Based on a survey, customers accepted the use of mobile devices for enabling a real-time information flow for improving customer satisfaction. A pilot test on vehicle routing was performed where the decision support system reduced the vehicle routing distance compared to the route taken by the driver. The three papers work in developing decision support systems for addressing major last mile transportation problems in parking and attended handover domains, thus improving customer satisfaction, and business opportunities, and reducing fuel costs, and pollution.
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Aspectos jurídicos da inseminação artificial heteróloga / Legal aspects of the heterologue artificial inseminationBarros, Eliane Oliveira 31 October 2007 (has links)
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Previous issue date: 2007-10-31 / The present article deals with the subject related to the Legal aspects of the
heterologue artificial insemination .
The objective of the study was to analyze the main problems related to this kind of
attended reproduction, among them: the probable users of this technique; to
discuss the possibility of attribution of the paternity results of the permission given
by the husband to the wife or by one companion to the other so that she submits
herself to therapeutical procedure; to consider if the child born through the use of
this technique can have access to the identity of the donator; to know if the donator
can be considered the father of the child.
The study is justified due to the scarce normative treatment given to the subject by
the Civil Code.
The article used method of qualitative bibliographical research. It had been
examined some works of reference that had best dealt with the subject among
available ones / A presente dissertação trata do tema relacionado aos Aspectos jurídicos da
inseminação artificial heteróloga .
Os objetivos da dissertação foram o de analisar os principais problemas
relacionados a este tipo de reprodução assistida, entre eles: os prováveis
destinatários dessa técnica; se a atribuição da paternidade pode decorrer do
consentimento dado pelo marido ou convivente para que a mulher ou a
companheira submeta-se ao procedimento terapêutico; se o nascido pela
utilização desta técnica pode obter dados que revelem a identidade do doador;
se o doador pode ser considerado o pai da criança.
Justifica-se o estudo diante do escasso tratamento normativo dado ao tema
pelo Código Civil.
A dissertação obedeceu método de pesquisa bibliografica qualitativa. Foram
examinadas algumas obras de referência que melhor trataram do assunto e
que se encontravam disponíveis
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Programa Liberdade assistida em Natal/RN: adolescentes em conflito com a lei e a viola??o de direitosPinheiro, Any Kadidja de Melo Tavares 10 December 2008 (has links)
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Previous issue date: 2008-12-10 / This work shows the results of the research: Attended Liberty Program Adolescents in Conflict with the Law and the Disapproval of Rights, effected in the community of Natal, Rio Grande do Norte, in period of august 2007 to September 2008. It aims to analyze the social-educative attendance directed to adolescents in conflict with the law through the state, since the Social-educative Measure Attended Liberty, known, as an idoneous way of confrontation to the practice of infraction acts imputed to the adolescent, that needs to give emphasis, in disadvantage of the Social-educative Measurement of Internment, to be proposed (ECA, art 118 and 199) to follow the adolescent in this quotidian, close to his family and community, proposing him through social-educative work, the access to education and occupancy, as well other public services, that help him to surpass the context of privation and disapproval of rights in which lives joined to his family. In our study, it was observed in sequence of approaching, subsidized for theoretical-methodological procedures justified in quantity and quality research, that were privileged to the documental research, the observation and the interview almost structured, besides a theoretical basis about the subject, that the relation of category and inequality in which the capitalist society sustains itself, does the practice of infraction acts imputed to the adolescent, acquires a classist character, in which the property of the money defines the access of the justice. And more, many of the poor adolescents that get into conflict with the law, dweller of the periphery districts of Natal/RN, becomes evident as for segment that has been attended in the Jurisdiction of the Infancy and Youth and in the LAN of Social-educative Attendance, becoming individual the infraction act and its confrontation. We hope in this work, to contribute for the care of the reality of the adolescent in conflict with the law in the Attended Liberty Program, without pretension to exhaust it, as well as later studies about the theme / Este trabalho apresenta os resultados da pesquisa: Programa Liberdade Assistida Adolescentes em Conflito com a Lei e a Viola??o de direitos, efetuada no munic?pio de Natal, Rio Grande do Norte, no per?odo de agosto de 2007 a setembro de 2008. Tem por objetivo analisar o atendimento s?cio-educativo direcionado ao adolescente em conflito com a lei fornecido pelo estado, a partir da Medida S?cio-Educativa Liberdade Assistida, compreendida enquanto um caminho de enfrentamento ? pr?tica de atos infracionais atribu?da ao adolescente, que precisa ser priorizada em detrimento da Medida S?cio-Educativa de Interna??o, por se propor a acompanhar o adolescente em seu cotidiano, junto ? sua fam?lia e comunidade, proporcionando-lhe, por meio do trabalho s?cio-educativo, o acesso ? escolariza??o e ? profissionaliza??o, bem como aos demais servi?os p?blicos que o ajudem a superar o contexto de priva??es e Viola??o de direitos em que vive juntamente com sua fam?lia. Em nosso estudo observou-se por aproxima??es sucessivas subsidiadas por procedimentos te?rico-metodol?gicos fundamentados na pesquisa quali-quantitativa, nos quais foram privilegiadas a pesquisa documental, a observa??o e a entrevista semi-estruturada, al?m de uma fundamenta??o te?rica a respeito do tema, que as rela??es de classe e de desigualdade sobre a qual a sociedade capitalista se sustenta, faz com que a pr?tica de atos infracionais atribu?da ao adolescente, adquira um car?ter classista, cuja propriedade determina o acesso a justi?a, individualizando o ato infracional e o seu enfrentamento. E mais: muitos dos adolescentes pobres, que se encontram em conflito com lei s?o moradores dos bairros perif?ricos de Natal/RN e se evidenciam quanto ao segmento que vem sendo atendido nas Varas da Inf?ncia e da Juventude e na Rede de Atendimento S?cio-Educativo. Espera-se, com este trabalho, contribuir para o desvelamento da realidade do adolescente em conflito com a lei no Programa Liberdade Assistida, sem pretens?o de esgotar o assunto, e subs?dio para posteriores estudos sobre o tema.
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Utilização de extração com CO2 supercrítico e de lixiviação assistida por ultra-som para a regeneração de catalisadores automotivosPimentel, Hélio Oliveira 14 December 2007 (has links)
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Tese Hélio O. Pimentel.pdf: 2196448 bytes, checksum: b81d660c75daf2b43a78c84dc7e07cf7 (MD5) / FINEP / CNPq / RECAT / Esta tese é uma contribuição na perspectiva de melhoramento da tecnologia
para o tratamento catalítico dos gases de emissão automotiva, reconhecidos como
poluentes ambientais. Os catalisadores ou conversores automotivos (Three-Way
Catalysts, TWC) são uma tecnologia bem estabelecida para o abatimento de gases
poluentes emitidos pelos veículos, mas esses sistemas desativam sob condições
severas às quais estão submetidas. As causas de desativação reconhecidas para o
TWC são: a exposição às altas temperaturas durante a operação do motor, que
causam danos ao washcoat e sinterização dos sítios ativos, bem como o depósito de
fases inativas como fosfatos, sulfatos e compostos carbonáceos, além de outros
venenos provenientes dos aditivos da gasolina e óleos lubrificantes. Muitos esforços
têm sido destinados à regeneração da atividade catalítica, aumentando a
durabilidade do TWC, por razões econômicas e ambientais. A remoção de fases
inativas, venenos e a redispersão das espécies ativas sinterizadas são algumas das
estratégias investigadas na literatura. Neste trabalho, amostras de conversores
envelhecidos num táxi, na condição real de tráfego em Salvador-Bahia-Brasil, foram
caracterizadas por MEV, FRX, DRX, TG, XPS, TPR e análises texturais, bem como
por testes de avaliação catalítica na redução de NO com CO, empregada como
reação modelo. Dois procedimentos de regeneração foram investigados: i) lixiviação
assistida por ultra-som (LUS), utilizando solventes e soluções diluídas de ácidos; e ii)
tratamento com fluido supercrítico de CO2 (FSC), usando metanol como agente
modificador. Como a eficiência da extração com CO2 supercrítico depende de vários
parâmetros, tais como temperatura, pressão e solventes modificadores, o estudo foi
realizado usando um planejamento fatorial 2k (k = 3). Ambos os procedimentos
mostraram-se promissores levando a recuperação da atividade catalítica. O ácido
clorídrico diluído mostrou-se o meio mais adequado para a lixiviação assistida por
ultra-som, removendo venenos e fases inativas, bem como causando redistribuição
das fases ativas de metais nobres. O tratamento com FSC também é eficiente, mas
as condições operacionais precisam ser bem controladas de modo a evitar danos
estruturais ao washcoat. As modificações texturais observadas, redispersão das
fases ativas, remoção de fases inativas e venenos, na condição de 100ºC, 1500 psi
e 10% de metanol, favoreceram a recuperação da atividade catalítica. / This thesis is a contribution in perspective to technology improvement of
catalytic treatment automotive gases, recognized as environmental pollutants.
Automotive catalysts (Three-Way Catalysts, TWC) are well established technology
for abatement of gaseous pollutants emitted from vehicles, however they deactivate
under the tough conditions to which they are subjected. The TWC deactivation
factors are recognized as the exposition at high temperatures during the motor
operation, due to the temperature sintering effects on alumina washcoat and active
sites, as inactive phase deposition like phosphates, sulfates, graphite and other
carbonaceous, and other poisons resultant of the gasoline and lubricant oil
addictives. A lot of effort has been applied in order to regenerate activity, thus
improving TWC durability, both for economical and environmental reasons. The
removal of inactive phases and poisons and re-dispersion of sintered active species
are some regeneration strategies that have been investigated in the literature. In this
work, samples of aged converters, in actual transit condition vehicle taxi fleet of
Salvador-Bahia-Brazil, were characterized by SEM, XRF, XRD, TG, XPS, TPR and
textural analysis, as well as, catalytic evaluation tests by the NO with CO reduction,
as the reaction model. Two regenerated proceedings were investigated: i) ultrasound
attended lixiviation (USL), with solvents and dilute acid solutions, and ii) CO2
supercritical fluid (SCF), with methanol as modifier agent. Once the efficiency of
supercritical fluid extraction depends on various parameters, such as temperature,
pressure and presence of modifier solvents, the study has been performed using a
factorial design 2k (k = 3). Both proceedings showed promising to carry the catalytic
activity regeneration. The dilute hydrochloric acid was the best adequate means to
the ultrasound attended lixiviation, removing poisons and inactive phases and
leading to the re-dispersion of active phases of noble metals. The SCF treatment is
also efficient; however, the operational conditions need to be well controlled to avoid
the washcoat structural damages. The observed textural modifiers, active phase re-
dispersion, inactive phases and poisons removal, in the condition of 100ºC, 1500 psi
and 10% methanol, aid the catalytic activity recovery.
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CRAbCVE- Uma arquitetura para viabilização de CVEs através da Internet / CRAbCVE- An Architecture for CVEs through the InternetGomes, George Allan Menezes January 2005 (has links)
GOMES, George Allan Menezes. CRAbCVE- Uma arquitetura para viabilização de CVEs através da Internet. 2005. 170 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Computação, Fortaleza-CE, 2005. / Submitted by guaracy araujo (guaraa3355@gmail.com) on 2016-06-30T19:31:13Z
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Previous issue date: 2005 / Although the complexities of many tasks encountered in modern societies require the join effort of groups of people in order to be accomplished, cooperative work is still a difficult job. Usually the difficulties arise due to lack of appropriate coordination, poor definition of the context in which the activities are to be performed individually or in group; thus, generating redundancies, inconsistencies and contradictions within the workgroup. In order to overcome these problems, a new field of research, called Computer Supported Cooperative Work (CSCW), was created to seek means of properly supporting work groups. Despite the favorable results achieved by CSCW, thus far, tools that provide a high level of interaction among the group members and the leaders of sub-groups are still not satisfactory. The use of virtual reality within cooperative systems allows the interactions among participants to be highly spontaneous, because, in virtual environments, communication by means of image, text and audio is possible. The Collaborative Virtual Environments (CVEs), which employ shared virtual reality technology, have proved to possess great potential for collaborative work. Therefore, collaborative virtual environments have been developed taking into consideration the results obtained by CSCW research. Nonetheless, developing CVEs is complicated, since they demand a great deal of resources, and need to incorporate concepts and recommendations from several research fields, such as Virtual Reality (VR), Computer Supported Cooperative Work and l Distributed Computing. The main objective of this dissertation is to design a generic architecture (CRAbCVE) for allowing distribution of several collaborative virtual environments within a network of servers on the Internet. This architecture defines specialized components, capable of distributing the processing that takes place in the CVE, thus obtaining a great computational power at low costs. Another important objective is the specification of a Model of Authorship in CVEs (MAC) for helping to integrate the CRAbCVE architecture into the framework of collaborative work. All models proposed herein have been incorporated into a prototype system and a simple case study has been analyzed. / A complexidade das tarefas do mundo atual requer cada vez mais a cooperação das pessoas para sua execução. Entretanto cooperar não é uma tarefa fácil, e, muitas vezes, por falta de coordenação adequada ou por uma definição pobre do contexto em que as atividades dos participantes individualmente ou do grupo serão realizadas, são geradas redundâncias, inconsistências e contradições dentro do trabalho em grupo. Para evitar esses problemas, a área de CSCW (Computer Supported Cooperative Work) vem buscando meios de suportar adequadamente o trabalho em equipe. Apesar dos bons resultados alcançados pela área de CSCW, o principal obstáculo enfrentado pelos seus desenvolvedores é fornecer interatividade a suas aplicações. O uso de realidade virtual em sistemas cooperativos permite aos participantes interagirem com o mais alto grau de naturalidade, pois através do ambiente virtual é possível a comunicação por meio de imagem, texto e áudio. Os CVEs (Collaborative Virtual Environments) fazem uso da tecnologia de realidade virtual distribuída e apresentam grande potencial para o suporte ao trabalho colaborativo. Por conseguinte, esses ambientes virtuais colaborativos têm sido desenvolvidos, levando em consideração os resultados obtidos na área de CSCW. Entretanto, desenvolver CVEs é uma tarefa complicada, pois eles são grandes consumidores de recursos, e precisam incorporar conceitos e recomendações de várias áreas de pesquisa, como a de Realidade Virtual (RV), a de Trabalho Colaborativo Assistido por Computador (CSCW) e a de Sistemas Computacionais Distribuídos. O principal objetivo dessa dissertação é a definição de uma arquitetura de uso genérico, a CRAbCVE, projetada para viabilizar vários Ambientes virtuais colaborativos (CVEs) distribuídos em uma rede de servidores na Internet. Essa arquitetura define componentes especializados, capazes de distribuir, através da Internet, o processamento de todo o CVE; obtendo-se, assim, um grande poder computacional a um baixo custo. Outro importante objetivo é a definição do modelo MAC (Modelo de Autoria em CVEs), que visa auxiliar o emprego da arquitetura CRAbCVE no trabalho colaborativo. Os modelos propostos foram incorporados em um sistema protótipo e um estudo de caso simples foi analisado
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A escolarização do aluno infrator: um estudo em duas escolas com alunos/adolescentes inseridos nas medidas sócio-educativas de prestação de serviços à comunidade e liberdade assistidaEscanuela, Paula de Castro 26 October 2009 (has links)
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Previous issue date: 2009-10-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / To search the formal process of adaptation at school of adolescent-students
those are judicially distinctive qualified as offenders and ordered to the educativesocial
step fulfillment in open way - Community Services Repayment (PSC) and
Attended Freedom (LA) - prescribed by the Federal Law nº 8069 of July 13th of 1990
institutes the Adolescent and Child Statute (ECA) that implied in the needs to set up
the searches beyond of the school borders and carrying an attentive reading about
the proper (ECA) such as in respect to its basic principles, applicability, beyond the
transformations and social impacts came from its implementation, in order to
understand what is the school function in the face to the educative-social step
process that offenders adolescent are submitted. The struggle about (ECA) will be
retaken in the analytical description of the data gotten through half-structuralized
research made to pedagogical coordinators and teacher in two public schools - one
municipal and other one state - located in a city from Sao Paulo State and also to
subsidiary data came from Judicial process studding about the students in (PSC) and
(LA), as well as the Youth and Childhood Judge statement and professionals
responsible for the educative-social step accompaniment related. The indicating
elements of the relations that schools establish to students in (PSC) and (LA) are
analyzed from the critical theoretical reference of those authors Adorno, Horkheimer
and Marcuse to the objective of verify how the formal process of adaptation at school
of the adolescent in question not only corroborates for guarantee their social right but
also to recovering or readjustment them to the society / Investigar o processo de escolarização formal de alunos/adolescentes
judicialmente tipificados como infratores e determinados ao cumprimento das
medidas sócio-educativas em meio aberto Prestação de Serviços à Comunidade
PSC e Liberdade Assistida LA prescritas pela Lei nº 8069 de 13 de julho de 1990,
que institui o Estatuto da Criança e do Adolescente implicou na necessidade de situar
a investigação para além das fronteiras da escola e realizar uma atenta leitura sobre
o próprio ECA, tanto no que concerne aos seus princípios fundamentais, sua
aplicabilidade, além das transformações e impactos sociais advindos de sua
implementação, a fim de entendermos qual a função da escola diante do processo
sócio-educativo a que são submetidos adolescentes infratores. A discussão sobre o
ECA foi retomada na descrição analítica dos dados obtidos através de entrevistas
semi-estruturadas realizadas com professores e coordenadores pedagógicas de duas
escolas públicas uma municipal e uma estadual - localizadas em uma cidade do
interior paulista e ainda de dados subsidiários oriundos da leitura dos processos
judiciais dos alunos em PSC e LA, bem como do depoimento do juiz da infância e
juventude e dos profissionais responsáveis pelo acompanhamento das referidas
medidas sócio-educativas. Os elementos indicadores das relações que as escolas
estabeleceram com os alunos em PSC e LA foram analisados a partir do referencial
teórico crítico dos autores Adorno, Horkheimer e Marcuse com o propósito de
verificar se a escolarização do adolescente em questão corroborou não somente para
garantia de um direito social mas para sua reinserção ou readaptação à
sociedade
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