This research, done as part of the mechanical engineering program at Linnaeus University in partnership with Rottne Industri AB, aims to improve safety in forest industri. It focuses on designing a user-friendly emergency exit system for harvester cabins. Driven by strict safety rules and societal expectations, the goal is to craft an exit that allows quick evacuation during emergencies and fits well with forest machinery safety standards.

Gehaltediens lei tot effektiwiteit in enige organisasie. Die meting hiervan behoort 'n prioriteit te wees, maar geskikte, gevalideerde, wetenskaplike meetinstrumente hiervoor bestaan nie. Die algemene doel van die navorsing was die validering van 'n gerekenariseerde simulasietegniek ("Business Principles Orientation") vir die meting van klientediensvaardighede. In die literatuuroorsig is klientediens gedefinieer en vyf dimensies van gehaltediens gei:dentifiseer. Deur empiriese navorsing is die gerekenariseerde simulasietegniek ("Business Principles Orientation") se meting van klientediensvaardighede bepaal, deur dit afte neem op 'n steekproef van 28 kassiere in 'n supermark. Hierdie instrument is gekorreleer met die Servqual-vraelys. Die resultate dui op 'n swak verband tussen die veranderlikes van die Servqual-vraelys en gerekenariseerde simulasietegniek. Hiervolgens is die gerekenariseerde simulasietegniek en die ontwikkelingsverslag wat dit verskaf, nie geldig in die meting van klientdiensvaardighede nie. Aanbevelings ten opsigte van die instrument se verdere verfyning en navorsing word geformuleer. / Quality service leads to effectiveness in any organisation. The measurement of effectiveness should be a priority, but suitable, valid and scientific measurement instruments for this purpose does not exist. The general aim of the research was the validation of a computerized simulation technique ("Business Principles Orientation") for the measurement of client service skills. In the literature survey, quality service was defined and five dimensions of quality service identified. In the empirical research the measurement of client service skills through the use of the computerized technique ("Business Priciples Orientation"), was determined by testing it on a sample of 28 cashiers from a supermarket. This instrument was correlated with the Servqual-questionaire. The results show little correlation between the variables of the Servqual questionaire and computerized simulation technique. In terms hereof the computerized simulation technique and development report that it provides, is not valid in the measurement of client care skills. Recommendations for further refinement and research pertaining to this instrument is formulated. / Industrial & Organisational Psychology / M.A. (Bedryfsielkunde)

O ensino da Engenharia por meios eletrônicos de aprendizagem demanda a implementação de métodos práticos que facilitem ao aluno aprender conteúdos do tipo procedimentos e atitudes, por meio da ação, da interação dos participantes, e da integração de conhecimentos de diferentes áreas. Esta aprendizagem só pode ser efetiva em contextos significativos e a partir de situações específicas, que são estimulados com a utilização do método de projeto. A eficácia deste método é alcançada quando utilizado em grupos, onde um membro aprende na integração com outro, compartilhando recursos e conhecimentos, e adquirindo ou exercitando um conjunto de habilidades pessoais, atualmente muito necessárias no trabalho profissional do Engenheiro. Embora conhecida a importância do método de projeto no estilo de aprendizagem colaborativa, não existem orientações para sua utilização no modelo de ensino-aprendizagem a distância. Este cenário representou a principal motivação para propor, neste trabalho, um modelo conceitual para aprendizagem colaborativa baseada na execução de projetos pela Web (MAC-BP). O modelo é organizado em três submodelos relacionados entre si, que caracterizam a criação, a execução e o suporte das atividades instrucionais colaborativas utilizadas no ensino da Engenharia. Um modelo para planejar as atividades e responsabilidades do especialista, encarregado pela criação do conteúdo e das atividades de grupo baseados no método de projeto; um modelo de colaboração que formaliza a coordenação das interações dos membros do grupo, através de um autômato finito; e um modelo para o ambiente de suporte às atividades instrucionais colaborativas, que busca integrar as funcionalidades requeridas pelos ambientes CSCL (Computer Supported Cooperative Learning), algumas presentes, porém dispersas, entre os sistemas disponíveis de suporte à colaboração. Por outro lado, a concepção das atividades instrucionais para grupos, além de representar uma tarefa que consome muito tempo, constitui um processo trabalhoso. Em geral, neste processo, a criação dos recursos envolvidos numa ação de aprendizagem específica está estreitamente relacionada ao formato da ferramenta utilizada para sua criação e gerenciamento, dificultando assim a reutilização dos elementos educacionais por novas aplicações. Este novo cenário converteu-se numa outra motivação para colaborar nesta área. Neste trabalho identificam-se os elementos (objetos e ações) compartilháveis de aprendizagem colaborativa envolvidos no modelo MAC-BP e propõe-se um conjunto de especificações técnicas para a criação e utilização destes elementos, segundo as especificações ADL-SCORM e IMS-LD divulgadas para o modelo de EAD orientado à aprendizagem individual. Assim, as duas propostas apresentadas neste trabalho pretendem contribuir com os esforços de padronização dos recursos e procedimentos de suporte ao ensino-aprendizagem, em sistemas eletrônicos de suporte à aprendizagem colaborativa na área de pesquisa dos sistemas CSCL. Especificamente, as propostas indicam caminhos para a inovação do processo pedagógico, e se constituem em guias para os instrutores na criação das aplicações de aprendizagem colaborativa baseadas em projeto e na criação dos elementos instrucionais envolvidos nelas, além de oferecer uma solução para a coordenação das interações colaborativas do grupo durante a execução de projetos, o que representa um suporte à aprendizagem em grupo na área de Engenharia. / Engineering Education in e-learning environments demands the implementation of practical methods that facilitates learning of contents of the type: procedures and attitudes by means of action, of the interaction among participants and the integration of knowledge of different fields. This learning can only be effective in significant contexts and from specific situations that are stimulated by using the project method. The effectiveness of this method is reached when used of preference in groups; in such a way that a participant learns with another by sharing resources and knowledge and acquiring or exercising a set of personal abilities, which are necessary for the professional work of the engineer. In spite of the well-recognized importance of the project method for collaborative e-learning, no comprehensive guidelines have yet been set out for distance education. This scenario represented the main motivation to propose a conceptual Model for Collaborative e-Learning Based on the execution of Web supported Projects (MAC-BP). This model is organized in three sub models related among them representing the creation, the execution, and the support of the collaborative instructional activities used in Engineering Teaching. One model is devoted to plan the activities and responsibilities of the specialist, the person in charge of the elaboration of contents and planning the activities of the group based on the project method. The second is a collaborative model aiming to formalize the coordination of the interactions among the members of the group, through a finite automaton. The last model is conceived as a supporting environment to the collaborative instructional activities aiming to integrate the functionalities required by CSCL (Computer Supported Cooperative Learning) environments, some of them already existing, however highly scattered among the available systems for supporting collaboration. On the other hand, the conception of instructional activities for groups is a time-consuming task and constitutes a laborious process. In general, the creation of the involved resources in a specific learning action is intimately related to the format of the tool used for its creation and management, making difficult to reuse the educational elements in new applications. This is a additional motivation to intend to make some contribution to this field. In this work, the shareable elements of collaborative learning (objects and actions) involved in the model MAC-BP are identified. In addition, a set of technical specifications is suggested for the elaboration and use of these elements, according to ADL-SCORM and IMS-LD specifications previously reported for the EAD model focused on individual learning. In summary, the two proposals showed in this work intend to contribute to the efforts of standardization of resources and procedures in order to support the teaching-learning process by means of electronic systems conceived to support the collaborative learning in the investigation of CSCL systems. These proposals indicate ways to innovate the pedagogical process, and constitute guides for instructors to develop new applications of project-based collaborative learning and the elaboration of the involved instructional elements. In addition, the proposals give a solution to the coordination of group collaborative interactions during the execution of projects and represent a support to collaborative learning in Engineering.

O ensino da Engenharia por meios eletrônicos de aprendizagem demanda a implementação de métodos práticos que facilitem ao aluno aprender conteúdos do tipo procedimentos e atitudes, por meio da ação, da interação dos participantes, e da integração de conhecimentos de diferentes áreas. Esta aprendizagem só pode ser efetiva em contextos significativos e a partir de situações específicas, que são estimulados com a utilização do método de projeto. A eficácia deste método é alcançada quando utilizado em grupos, onde um membro aprende na integração com outro, compartilhando recursos e conhecimentos, e adquirindo ou exercitando um conjunto de habilidades pessoais, atualmente muito necessárias no trabalho profissional do Engenheiro. Embora conhecida a importância do método de projeto no estilo de aprendizagem colaborativa, não existem orientações para sua utilização no modelo de ensino-aprendizagem a distância. Este cenário representou a principal motivação para propor, neste trabalho, um modelo conceitual para aprendizagem colaborativa baseada na execução de projetos pela Web (MAC-BP). O modelo é organizado em três submodelos relacionados entre si, que caracterizam a criação, a execução e o suporte das atividades instrucionais colaborativas utilizadas no ensino da Engenharia. Um modelo para planejar as atividades e responsabilidades do especialista, encarregado pela criação do conteúdo e das atividades de grupo baseados no método de projeto; um modelo de colaboração que formaliza a coordenação das interações dos membros do grupo, através de um autômato finito; e um modelo para o ambiente de suporte às atividades instrucionais colaborativas, que busca integrar as funcionalidades requeridas pelos ambientes CSCL (Computer Supported Cooperative Learning), algumas presentes, porém dispersas, entre os sistemas disponíveis de suporte à colaboração. Por outro lado, a concepção das atividades instrucionais para grupos, além de representar uma tarefa que consome muito tempo, constitui um processo trabalhoso. Em geral, neste processo, a criação dos recursos envolvidos numa ação de aprendizagem específica está estreitamente relacionada ao formato da ferramenta utilizada para sua criação e gerenciamento, dificultando assim a reutilização dos elementos educacionais por novas aplicações. Este novo cenário converteu-se numa outra motivação para colaborar nesta área. Neste trabalho identificam-se os elementos (objetos e ações) compartilháveis de aprendizagem colaborativa envolvidos no modelo MAC-BP e propõe-se um conjunto de especificações técnicas para a criação e utilização destes elementos, segundo as especificações ADL-SCORM e IMS-LD divulgadas para o modelo de EAD orientado à aprendizagem individual. Assim, as duas propostas apresentadas neste trabalho pretendem contribuir com os esforços de padronização dos recursos e procedimentos de suporte ao ensino-aprendizagem, em sistemas eletrônicos de suporte à aprendizagem colaborativa na área de pesquisa dos sistemas CSCL. Especificamente, as propostas indicam caminhos para a inovação do processo pedagógico, e se constituem em guias para os instrutores na criação das aplicações de aprendizagem colaborativa baseadas em projeto e na criação dos elementos instrucionais envolvidos nelas, além de oferecer uma solução para a coordenação das interações colaborativas do grupo durante a execução de projetos, o que representa um suporte à aprendizagem em grupo na área de Engenharia. / Engineering Education in e-learning environments demands the implementation of practical methods that facilitates learning of contents of the type: procedures and attitudes by means of action, of the interaction among participants and the integration of knowledge of different fields. This learning can only be effective in significant contexts and from specific situations that are stimulated by using the project method. The effectiveness of this method is reached when used of preference in groups; in such a way that a participant learns with another by sharing resources and knowledge and acquiring or exercising a set of personal abilities, which are necessary for the professional work of the engineer. In spite of the well-recognized importance of the project method for collaborative e-learning, no comprehensive guidelines have yet been set out for distance education. This scenario represented the main motivation to propose a conceptual Model for Collaborative e-Learning Based on the execution of Web supported Projects (MAC-BP). This model is organized in three sub models related among them representing the creation, the execution, and the support of the collaborative instructional activities used in Engineering Teaching. One model is devoted to plan the activities and responsibilities of the specialist, the person in charge of the elaboration of contents and planning the activities of the group based on the project method. The second is a collaborative model aiming to formalize the coordination of the interactions among the members of the group, through a finite automaton. The last model is conceived as a supporting environment to the collaborative instructional activities aiming to integrate the functionalities required by CSCL (Computer Supported Cooperative Learning) environments, some of them already existing, however highly scattered among the available systems for supporting collaboration. On the other hand, the conception of instructional activities for groups is a time-consuming task and constitutes a laborious process. In general, the creation of the involved resources in a specific learning action is intimately related to the format of the tool used for its creation and management, making difficult to reuse the educational elements in new applications. This is a additional motivation to intend to make some contribution to this field. In this work, the shareable elements of collaborative learning (objects and actions) involved in the model MAC-BP are identified. In addition, a set of technical specifications is suggested for the elaboration and use of these elements, according to ADL-SCORM and IMS-LD specifications previously reported for the EAD model focused on individual learning. In summary, the two proposals showed in this work intend to contribute to the efforts of standardization of resources and procedures in order to support the teaching-learning process by means of electronic systems conceived to support the collaborative learning in the investigation of CSCL systems. These proposals indicate ways to innovate the pedagogical process, and constitute guides for instructors to develop new applications of project-based collaborative learning and the elaboration of the involved instructional elements. In addition, the proposals give a solution to the coordination of group collaborative interactions during the execution of projects and represent a support to collaborative learning in Engineering.

The aim of this thesis is to assess the suitability of cold-formed rectangular hollow sections (RHS) for plastic design. The project involved an extensive range of tests on cold-formed Grade C350 and Grade C450 (DuraGal) RHS beams, joints and frames. A large number of finite element analyses was also carried out on models of RHS beams. The conclusion is that cold- formed RHS can be used in plastic design, but stricter element slenderness (b/t) limits and consideration of the connections, are required. Further research, particularly into the effect of axial compression on element slenderness limits, is required before changes to current design rules can be finalised. Bending tests were performed on cold-formed RHS to examine the web and flange slenderness required to maintain the plastic moment for a large enough rotation suitable for plastic design. The major conclusions of the beam tests were: (i) Some sections which are classified as Compact or Class 1 by current steel design specifications do not maintain plastic rotations considered sufficient for plastic design. (ii) The current design philosophy, in which flange and web slenderness limits are independent, is inappropriate. An interaction formula is required, and simple formulations are proposed for RHS. Connection tests were performed on various types of knee joints in RHS, suitable for the column - rafter connection in a portal frame. The connection types investigated were welded stiffened and unstiffened rigid knee connections, bolted plate knee joints, and welded and bolted internal sleeve knee joints, for use in RHS portal frames. The ability of the connections to act as plastic hinges in a portal frame was investigated. The most important finding of the joint tests was the unexpected fracture of the cold-formed welded connections under opening moment before significant plastic rotations occurred. The use of an internal sleeve moved the plastic hinge in the connection away from the connection centre- line thus eliminating the need for the weld between the RHS, or the RHS and the stiffening plate, to carry the majority of the load. The internal sleeve connections were capable of sustaining the plastic moment for large rotations considered suitable for plastic design. Tests on pinned-base portal frames were also performed. There were three separate tests, with two different ratios of vertical to horizontal point loads, simulating gravity and horizontal wind loads. Two grades of steel were used for comparison. The aims of the tests were to examine if a plastic collapse mechanism could form in a cold-formed RHS frame, and to investigate if plastic design was suitable for such frames. In each frame, two regions of highly concentrated curvature were observed before the onset of local buckling, which indicated the formation of plastic hinges and a plastic collapse mechanism. An advanced plastic zone structural analysis which accounted for second order effects, material non-linearity and member imperfections slightly overestimated the strength of the frames. The analysis slightly underestimated the deflections, and hence the magnitude of the second order effects. A second order plastic zone analysis, which did not account for the effects of structural imperfections, provided the best estimates of the strengths of the frames, but also underestimated the deflections. While cold-formed RHS did not satisfy the material ductility requirements specified for plastic design in some current steel design standards, plastic hinges and plastic collapse mechanisms formed. This suggests that the restriction on plastic design for cold-formed RHS based on insufficient material ductility is unnecessary, provided that the connections are suitable for plastic hinge formation, if required. A large number of finite element analyses were performed to simulate the bending tests summarised above, and to examine various parameters not studied in the experimental investigation. To simulate the experimental rotation capacity of the RHS beams, a sinusoidally varying longitudinal local imperfection was prescribed. The finite element analysis determined similar trends as observed experimentally, namely that the rotation capacity depended on both the web slenderness and flange slenderness, and that for a given section aspect ratio, the relationship between web slenderness and rotation capacity was non-linear. The main finding of the finite element study was that the size of the imperfections had an unexpectedly large influence on the rotation capacity. Larger imperfections were required in the more slender sections to simulate the experimental results. There should be further investigation into the effect of varying material properties on rotation capacity.

No description available.

No description available.

No description available.

The aim of this thesis is to assess the suitability of cold-formed rectangular hollow sections (RHS) for plastic design. The project involved an extensive range of tests on cold-formed Grade C350 and Grade C450 (DuraGal) RHS beams, joints and frames. A large number of finite element analyses was also carried out on models of RHS beams. The conclusion is that cold- formed RHS can be used in plastic design, but stricter element slenderness (b/t) limits and consideration of the connections, are required. Further research, particularly into the effect of axial compression on element slenderness limits, is required before changes to current design rules can be finalised. Bending tests were performed on cold-formed RHS to examine the web and flange slenderness required to maintain the plastic moment for a large enough rotation suitable for plastic design. The major conclusions of the beam tests were: (i) Some sections which are classified as Compact or Class 1 by current steel design specifications do not maintain plastic rotations considered sufficient for plastic design. (ii) The current design philosophy, in which flange and web slenderness limits are independent, is inappropriate. An interaction formula is required, and simple formulations are proposed for RHS. Connection tests were performed on various types of knee joints in RHS, suitable for the column - rafter connection in a portal frame. The connection types investigated were welded stiffened and unstiffened rigid knee connections, bolted plate knee joints, and welded and bolted internal sleeve knee joints, for use in RHS portal frames. The ability of the connections to act as plastic hinges in a portal frame was investigated. The most important finding of the joint tests was the unexpected fracture of the cold-formed welded connections under opening moment before significant plastic rotations occurred. The use of an internal sleeve moved the plastic hinge in the connection away from the connection centre- line thus eliminating the need for the weld between the RHS, or the RHS and the stiffening plate, to carry the majority of the load. The internal sleeve connections were capable of sustaining the plastic moment for large rotations considered suitable for plastic design. Tests on pinned-base portal frames were also performed. There were three separate tests, with two different ratios of vertical to horizontal point loads, simulating gravity and horizontal wind loads. Two grades of steel were used for comparison. The aims of the tests were to examine if a plastic collapse mechanism could form in a cold-formed RHS frame, and to investigate if plastic design was suitable for such frames. In each frame, two regions of highly concentrated curvature were observed before the onset of local buckling, which indicated the formation of plastic hinges and a plastic collapse mechanism. An advanced plastic zone structural analysis which accounted for second order effects, material non-linearity and member imperfections slightly overestimated the strength of the frames. The analysis slightly underestimated the deflections, and hence the magnitude of the second order effects. A second order plastic zone analysis, which did not account for the effects of structural imperfections, provided the best estimates of the strengths of the frames, but also underestimated the deflections. While cold-formed RHS did not satisfy the material ductility requirements specified for plastic design in some current steel design standards, plastic hinges and plastic collapse mechanisms formed. This suggests that the restriction on plastic design for cold-formed RHS based on insufficient material ductility is unnecessary, provided that the connections are suitable for plastic hinge formation, if required. A large number of finite element analyses were performed to simulate the bending tests summarised above, and to examine various parameters not studied in the experimental investigation. To simulate the experimental rotation capacity of the RHS beams, a sinusoidally varying longitudinal local imperfection was prescribed. The finite element analysis determined similar trends as observed experimentally, namely that the rotation capacity depended on both the web slenderness and flange slenderness, and that for a given section aspect ratio, the relationship between web slenderness and rotation capacity was non-linear. The main finding of the finite element study was that the size of the imperfections had an unexpectedly large influence on the rotation capacity. Larger imperfections were required in the more slender sections to simulate the experimental results. There should be further investigation into the effect of varying material properties on rotation capacity.

Gehaltediens lei tot effektiwiteit in enige organisasie. Die meting hiervan behoort 'n prioriteit te wees, maar geskikte, gevalideerde, wetenskaplike meetinstrumente hiervoor bestaan nie. Die algemene doel van die navorsing was die validering van 'n gerekenariseerde simulasietegniek ("Business Principles Orientation") vir die meting van klientediensvaardighede. In die literatuuroorsig is klientediens gedefinieer en vyf dimensies van gehaltediens gei:dentifiseer. Deur empiriese navorsing is die gerekenariseerde simulasietegniek ("Business Principles Orientation") se meting van klientediensvaardighede bepaal, deur dit afte neem op 'n steekproef van 28 kassiere in 'n supermark. Hierdie instrument is gekorreleer met die Servqual-vraelys. Die resultate dui op 'n swak verband tussen die veranderlikes van die Servqual-vraelys en gerekenariseerde simulasietegniek. Hiervolgens is die gerekenariseerde simulasietegniek en die ontwikkelingsverslag wat dit verskaf, nie geldig in die meting van klientdiensvaardighede nie. Aanbevelings ten opsigte van die instrument se verdere verfyning en navorsing word geformuleer. / Quality service leads to effectiveness in any organisation. The measurement of effectiveness should be a priority, but suitable, valid and scientific measurement instruments for this purpose does not exist. The general aim of the research was the validation of a computerized simulation technique ("Business Principles Orientation") for the measurement of client service skills. In the literature survey, quality service was defined and five dimensions of quality service identified. In the empirical research the measurement of client service skills through the use of the computerized technique ("Business Priciples Orientation"), was determined by testing it on a sample of 28 cashiers from a supermarket. This instrument was correlated with the Servqual-questionaire. The results show little correlation between the variables of the Servqual questionaire and computerized simulation technique. In terms hereof the computerized simulation technique and development report that it provides, is not valid in the measurement of client care skills. Recommendations for further refinement and research pertaining to this instrument is formulated. / Industrial and Organisational Psychology / M.A. (Bedryfsielkunde)