895 resultados para Process Re-engineering


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Mode of access: Internet.

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This paper presents a critical comparison of major changes in engineering education in both Australia and Europe. European engineering programs are currently being reshaped by the Bologna process, representing a move towards quality assurance in higher education and the mutual recognition of degrees among universities across Europe. Engineering education in Australia underwent a transformation after the 1996 review of engineering education1. The paper discusses the recent European developments in order to give up-to-date information on this fast changing and sometimes obscure process. The comparison draws on the implications of the Bologna Process on the German engineering education system as an example. It concludes with issues of particular interest, which can help to inform the international discussion on how to meet today’s challenges for engineering education. These issues include ways of achieving diversityamong engineering programs, means of enabling student and staff mobility, and the preparation of engineering students for professional practic e through engineering education. As a result, the benefits of outcomes based approaches in education are discussed. This leads to an outlook for further research into the broader attributes required by future professional engineers. © 2005, Australasian Association for Engineering Education

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Orally disintegrating tablets (ODTs) which are also referred to as orodispersible and fast disintegrating tablets, are solid oral dosage forms which upon placing on the tongue, disperse/disintegrate rapidly before being swallowed as a suspension or solution. ODTs are therefore easier and more convenient to administer than conventional tablets and are particularly beneficial for paediatric and geriatric patients, who generally have difficulty swallowing their medication. The work presented in this thesis involved the formulation and process development of ODTs, prepared using freeze-drying. Gelatin is one of the principal excipients used in the formulation of freeze-dried ODTs. One of the studies presented in this thesis investigated the potential modification of the properties of this excipient, in order to improve the performance of the tablets. As gelatin is derived from animal sources, a number of ethical issues surround its use as an excipient in pharmaceutical preparations. This was one of the motivations, Methocel™ and Kollicoat® IR were evaluated as binders as alternative materials to gelatin. Polyox™ was also evaluated as a binder together with its potential uses as a viscosity increasing and mucoadhesive agent to increase the retention of tablets in the mouth to encourage pre-gastric absorption of active pharmaceutical ingredients (APIs). The in vitro oral retention of freeze-dried ODT formulations was one property which was assessed in a design of experiments – factorial design study, which was carried out to further understand the role that formulation excipients have on the properties of the tablets. Finally, the novel approach of incorporating polymeric nanoparticles in freeze-dried ODTs was investigated, to study if the release profile of APIs could be modified, which could improve their therapeutic effect. The results from these studies demonstrated that the properties of gelatin-based formulations can be modified by adjusting pH and ionic strength. Adjustment of formulation pH has shown to significantly reduce tablet disintegration time. Evaluating Methocel™, in particular low viscosity grades, and Kollicoat® IR as binders has shown that these polymers can form tablets of satisfactory hardness and disintegration time. Investigating Polyox™ as an excipient in freeze-dried ODT formulations revealed that low viscosity grades appear suitable as binders whilst higher viscosity grades could potentially be utilised as viscosity increasing and mucoadhesive agents. The design of experiments – factorial design study revealed the influence of individual excipients in a formulation mix on resultant tablet properties and in vitro oral retention of APIs. Novel methods have been developed, which allows the incorporation of polymeric nanoparticles in situ in freeze-dried ODT formulations, which allows the modification of the release profile of APIs.

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A semi-batch pyrolysis process was used to recover samples carbon fibre and glass fibre from their respective wastes. The mechanical properties of the recovered fibres were tested and compared to those of virgin fibres, showing good retention of the fibre properties. The recovered fibres were then used to prepare new LDPE composite materials with commercial and laboratory-synthesized compatibilizers. Mild oxidation of the post-pyrolysis recovered fibres and the use of different compatibilizers gave significant improvements in the mechanical properties of the LDPE composites; however some of the manufactured composites made from recovered fibres had properties similar to those made from virgin fibres.

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A recently developed novel biomass fuel pellet, the Q’ Pellet, offers significant improvements over conventional white pellets, with characteristics comparable to those of coal. The Q’ Pellet was initially created at bench scale using a proprietary die and punch design, in which the biomass was torrefied in-situ¬ and then compressed. To bring the benefits of the Q’ Pellet to a commercial level, it must be capable of being produced in a continuous process at a competitive cost. A prototype machine was previously constructed in a first effort to assess continuous processing of the Q’ Pellet. The prototype torrefied biomass in a separate, ex-situ reactor and transported it into a rotary compression stage. Upon evaluation, parts of the prototype were found to be unsuccessful and required a redesign of the material transport method as well as the compression mechanism. A process was developed in which material was torrefied ex-situ and extruded in a pre-compression stage. The extruded biomass overcame multiple handling issues that had been experienced with un-densified biomass, facilitating efficient material transport. Biomass was extruded directly into a novel re-designed pelletizing die, which incorporated a removable cap, ejection pin and a die spring to accommodate a repeatable continuous process. Although after several uses the die required manual intervention due to minor design and manufacturing quality limitations, the system clearly demonstrated the capability of producing the Q’ Pellet in a continuous process. Q’ Pellets produced by the pre-compression method and pelletized in the re-designed die had an average dry basis gross calorific value of 22.04 MJ/kg, pellet durability index of 99.86% and dried to 6.2% of its initial mass following 24 hours submerged in water. This compares well with literature results of 21.29 MJ/kg, 100% pellet durability index and <5% mass increase in a water submersion test. These results indicate that the methods developed herein are capable of producing Q’ Pellets in a continuous process with fuel properties competitive with coal.

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It has become increasingly common for tasks traditionally carried out by engineers to be undertaken by technicians and technologist with access to sophisticated computers and software that can often perform complex calculations that were previously the responsibility of engineers. Not surprisingly, this development raises serious questions about the future role of engineers and the education needed to address these changes in technology as well as emerging priorities from societal to environmental challenges. In response to these challenges, a new design module was created for undergraduate engineering students to design and build temporary shelters for a wide variety of end users from refugees, to the homeless and children. Even though the module provided guidance on principles of design thinking and methods for observing users needs through field studies, the students found it difficult to respond to needs of specific end users but instead focused more on purely technical issues.

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Desde hace cerca de dos siglos, los hidratos de gas han ganado un rol importante en la ingeniería de procesos, debido a su impacto económico y ambiental en la industria -- Cada día, más compañías e ingenieros ganan interés en este tema, a medida que nuevos desafíos muestran a los hidratos de gas como un factor crucial, haciendo su estudio una solución para un futuro próximo -- Los gases de hidrato son estructuras similares al hielo, compuestos de moléculas huéspedes de agua conteniendo compuestos gaseosos -- Existen naturalmente en condiciones de presiones altas y bajas temperaturas, condiciones típicas de algunos procesos químicos y petroquímicos [1] -- Basado en el trabajo doctoral de Windmeier [2] y el trabajo doctoral the Rock [3], la descripción termodinámica de las fases de los hidratos de gas es implementada siguiendo el estado del arte de la ciencia y la tecnología -- Con ayuda del Dortmund Data Bank (DDB) y el paquete de software correspondiente (DDBSP) [26], el desempeño del método fue mejorado y comparado con una gran cantidad de datos publicados alrededor del mundo -- También, la aplicabilidad de la predicción de los hidratos de gas fue estudiada enfocada en la ingeniería de procesos, con un caso de estudio relacionado con la extracción, producción y transporte del gas natural -- Fue determinado que la predicción de los hidratos de gas es crucial en el diseño del proceso del gas natural -- Donde, en las etapas de tratamiento del gas y procesamiento de líquido no se presenta ninguna formación, en la etapa de deshidratación una temperatura mínima de 290.15 K es crítica y para la extracción y transporte el uso de inhibidores es esencial -- Una composición másica de 40% de etilenglicol fue encontrada apropiada para prevenir la formación de hidrato de gas en la extracción y una composición másica de 20% de metanol en el transporte

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Cassava contributes significantly to biobased material development. Conventional approaches for its bio-derivative-production and application cause significant wastes, tailored material development challenges, with negative environmental impact and application limitations. Transforming cassava into sustainable value-added resources requires redesigning new approaches. Harnessing unexplored material source, and downstream process innovations can mitigate challenges. The ultimate goal proposed an integrated sustainable process system for cassava biomaterial development and potential application. An improved simultaneous release recovery cyanogenesis (SRRC) methodology, incorporating intact bitter cassava, was developed and standardized. Films were formulated, characterised, their mass transport behaviour, simulating real-distribution-chain conditions quantified, and optimised for desirable properties. Integrated process design system, for sustainable waste-elimination and biomaterial development, was developed. Films and bioderivatives for desired MAP, fast-delivery nutraceutical excipients and antifungal active coating applications were demonstrated. SRRC-processed intact bitter cassava produced significantly higher yield safe bio-derivatives than peeled, guaranteeing 16% waste-elimination. Process standardization transformed entire root into higher yield and clarified colour bio-derivatives and efficient material balance at optimal global desirability. Solvent mass through temperature-humidity-stressed films induced structural changes, and influenced water vapour and oxygen permeability. Sevenunit integrated-process design led to cost-effectiveness, energy-efficient and green cassava processing and biomaterials with zero-environment footprints. Desirable optimised bio-derivatives and films demonstrated application in desirable in-package O2/CO2, mouldgrowth inhibition, faster tablet excipient nutraceutical dissolutions and releases, and thymolencapsulated smooth antifungal coatings. Novel material resources, non-root peeling, zero-waste-elimination, and desirable standardised methodology present promising process integration tools for sustainable cassava biobased system development. Emerging design outcomes have potential applications to mitigate cyanide challenges and provide bio-derivative development pathways. Process system leads to zero-waste, with potential to reshape current style one-way processes into circular designs modelled on nature's effective approaches. Indigenous cassava components as natural material reinforcements, and SRRC processing approach has initiated a process with potential wider deployment in broad product research development. This research contributes to scientific knowledge in material science and engineering process design.

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Gli oli microbici stanno ricevendo sempre più attenzioni come possibile alternativa agli oli vegetali, nel processo di sostituzione dei combustibili fossili. Tuttavia, diversi aspetti necessitano di essere ottimizzati al fine di ottenere oli economicamente competitivi e con caratteristiche chimico-fisiche desiderate. In questa ricerca, sono stati utilizzati due differenti approcci per poter realizzare l’obiettivo preposto. Il primo, si è basato sull’ingegnerizzazione genetica del lievito C. oleaginous, al fine di incrementare la produttività di lipidi e modificare la composizione dei trigliceridi (TAG) sintetizzati. Un protocollo basato su una trasformazione genetica mediata da Agrobacterium è stato utilizzato per sovraesprimere la diacilglicerol trasnferasi (DGA1), l’enzima responsabile dell’ultimo step della sintesi dei TAG, e la Δ9-desaturasi, l’enzima che catalizza la conversione dell’acido stearico (C18:0) in acido oleico (C18:1). La selezione di colonie positive e l’analisi dei mutanti ottenuti ha confermato la buona riuscita della trasformazione. Il secondo approccio ha mirato a studiare l’influenza sulla crescita e sul profilo di lipidi accumulati da C. oleaginous da parte di diversi acidi grassi volatili (VFAs), una materia prima ottenibile da trattamenti di scarti industriali. A questo proposito, sono state utilizzate fermentazioni fed-batch su scala da 1-L basate su glucosio e miscele sintetiche di acido acetico e di VFAs come fonte di carbonio. L’utilizzo simultaneo di acido acetico e acidi secondari ha mostrato come sia possibile stimolare il metabolismo microbico al fine di incrementare l'accumulo di oli e ottenere una composizione chimica lipidica desiderata.

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This paper proposes an architecture for machining process and production monitoring to be applied in machine tools with open Computer numerical control (CNC). A brief description of the advantages of using open CNC for machining process and production monitoring is presented with an emphasis on the CNC architecture using a personal computer (PC)-based human-machine interface. The proposed architecture uses the CNC data and sensors to gather information about the machining process and production. It allows the development of different levels of monitoring systems with mininium investment, minimum need for sensor installation, and low intrusiveness to the process. Successful examples of the utilization of this architecture in a laboratory environment are briefly described. As a Conclusion, it is shown that a wide range of monitoring solutions can be implemented in production processes using the proposed architecture.