955 resultados para Solar Tower Technology


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Traditional methods of isolated MOSFET/IGBT gate drive are presented, and their pros and cons assessed. The best options are chosen to meet our objective— a small, high speed, low cost, low power isolated gate drive module. Two small ferrite bead transformers are used for isolation, one transmits power at 2.5MHz, the other sends narrow set reset pulses. On the secondary these pulses drive a transistor totem pole to ensure high current drive, and the value is held by CMOS buffers with positive feedback. An alternative design for driving logic level devices uses only an HC buffer on the secondary. Double sided SMDconstruction (primary one side, secondary on the other) yields an upright module 40x18x5mm. Propagation delaywas 20ns, and rise/fall time 15ns with a 1nF load. The design places no limits on frequency of operation or duty cycle. Power supply requirementswere 5V@20mA for operation below 100kHz, dominated by magnetising current.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Governments have recognised that the technological trades rely on knowledge embedded traditionally in science, technology, engineering and mathematics (STEM) disciplines. However, there is substantial evidence that students are turning away from these subjects in schools because the school curriculum is seen as irrelevant, with clear implications for not just vocational education but also higher education. In this paper, we report preliminary findings on the development of two curricula that attempt to integrate science and mathematics with workplace knowledge and practices. We argue that these curricula provide educational opportunities for students to pursue their preferred career pathways. These curricula were co-developed by industry and educational personnel across three industry sectors, namely, mining industry, aerospace and wine tourism. The aim was to provide knowledge appropriate for students moving from school to the workplace as trade apprentices in the respective industries. The analysis of curriculum and associated policy documents reveals that the curricula adopt applied learning orientations through teaching strategies and assessment practices which focus on practical skills. However, although key theoretical science and maths concepts have been well incorporated, the extent to which knowledge deriving from workplace practices is included varies across the curricula. The extent to which applications of concepts are included in the models depends on a number of factors not least the relevant expertise of the teacher as a practitioner in the industry. Our findings highlight the importance of teachers having substantial practical industry experience and the role that whole school policies play in attempts to align the range of learning experiences with the needs of industry.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

As we race towards a new era, rapid change of conventional models has become the norm. Just as technology has etched itself to the core of society, the sheer quantity of student devices connecting to university networks presents a sector wide challenge coinciding almost perfectly with many universities creating technology rich learning spaces. New fears include future proofing. It is not just a matter of technology becoming outdated. In seeking to accommodate the teaching styles and experience of staff across diverse faculties, is this technology simply too vanilla to meet their needs as they become increasingly skilled and inspired by technology’s potential? Through the early findings of a study into staff use of technology within Queensland University of Technology's next generation collaborative learning spaces, this paper explores whether the answers lie in a model presented by students equipping themselves with the tools they need to learn in the 21st century.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis is a comprehensive study of the synthesis of nanomaterials. It explores the synthetic methods on the control of the size, shape and phase of semiconductor nanocrystals. A number of important conclusions, including the mechanism behind crystal growth and the structure-relationship, have been drawn through the experimental and theoretical investigation. The synthesized nanocrystals have been tested for applications in gas sensing, photocatalysis and solar cells, which exhibit considerable commercialization potential.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis studied technology’s role in promoting and supporting active lifestyles through behavioural strategies to reduce sedentary time and increase physical activity. The five studies included (1) development of a self-report instrument quantifying daily sedentary behaviour and light-intensity physical activity; (2) establishment of instrument validity and reliability; (3) use of an online personal activity monitor to successfully reduce sedentary time and increase physical activity; (4) identification of positive differences in total wellness as related to high/low levels of sitting time combined with insufficient/sufficient physical activity; and (5) improvement of total wellness through positive changes in sedentary behaviour and physical activity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Through practice-led research, TESSA SMALLHORN examines the influence of digital technology on the performance space. From the mechanisation of modernist culture to the digitalisation of present day, technology acts as response material for scenographers investigating the stage as machine. The interactive, real-time tools of digital culture encourage a systems-orientated approach that challenges user and operator alike. This article explores the studio practice and critical theory that was combined to offer a functional model of a digital stage machine.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A controlled layer of multi-wall carbon nanotubes (MWCNT) was grown directly on top of fluorine-doped tin oxide (FTO) glass electrodes as a surface modifier for improving the performance of polymer solar cells. By using low-temperature chemical vapor deposition with short synthesis times, very short MWCNTs were grown, these uniformly decorating the FTO surface. The chemical vapor deposition parameters were carefully refined to balance the tube size and density, while minimizing the decrease in conductivity and light harvesting of the electrode. As created FTO/CNT electrodes were applied to bulk-heterojunction polymer solar cells, both in direct and inverted architecture. Thanks to the inclusion of MWCNT and the consequent nano-structuring of the electrode surface, we observe an increase in external quantum efficiency in the wavelength range from 550 to 650 nm. Overall, polymer solar cells realized with these FTO/CNT electrodes attain power conversion efficiency higher than 2%, outclassing reference cells based on standard FTO electrodes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Using ZnO seed layers, an efficient approach for enhancing the heterointerface quality of electrodeposited ZnO–Cu2O solar cells is devised. We introduce a sputtered ZnO seed layer followed by the sequential electrodeposition of ZnO and Cu2O films. The seed layer is employed to control the growth and crystallinity and to augment the surface area of the electrodeposited ZnO films, thereby tuning the quality of the ZnO–Cu2O heterointerface. Additionally, the seed layer also assists in forming high quality ZnO films, with no pin-holes, in a high pH electrolyte solution. X-ray electron diffraction patterns, scanning electron and atomic force microscopy images, as well as photovoltaic measurements, clearly demonstrate that the incorporation of certain seed layers results in the alteration of the heterointerface quality, a change in the heterojunction area and the crystallinity of the films near the junction, which influence the current density of photovoltaic devices.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study addresses the research question: ‘What are the diffusion determinants for extreme weather-proofing technology in the Australian built environment?’ In order to effectively identify diffusion determinants, a synthesis of literature in both technical and management fields was conducted from a system-wide perspective. Review results where then interpreted through an innovation system framework, drawn from innovation systems literature, in order to map the current state of extreme weather-proofing technology diffusion in the Australian built environment industry. Drivers and obstacles to optimal diffusion are presented. Results show the important role to be played by Australian governments in facilitating improved weather proofing technology diffusion. This applies to governments in their various roles, but particularly as regulators, clients/owners and investors in research & development and education. In the role as regulators, findings suggest Australian governments should be encouraging the application of innovative finance options and positive end-user incentives to promote the uptake of weather proofing technology. Additionally, in their role as clients/owners, diffusion can be improved by adjusting building and infrastructure specifications to encourage designers and constructors to incorporate extreme weather proofing technology in new and redeveloped built assets. Finally, results suggest greater investment is required in research and development and improved knowledge sharing across the construction supply chain to further mitigate risks associated with greater incidences of extreme weather events.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Technology has advanced in such a manner that the world can now communicate in means previously never thought possible. These new technologies have not been overlooked by transnational organized crime groups and networks of corruption, and have been exploited for criminal success. This text explores the use of communication interception technology (CIT), such as phone taps or email interception, and its potential to cause serious disruption to these criminal enterprises. Exploring the placement of communication interception technology within differing policing frameworks, and how they integrate in a practical manner, the authors demonstrate that CIT is best placed within a proactive, intelligence-led policing framework. They also indicate that if law enforcement agencies in Western countries are serious about fighting transnational organized crime and combating corruption, there is a need to re-evaluate the constraints of interception technology, and the sceptical culture that surrounds intelligence in policing. Policing Transnational Organized Crime and Corruption will appeal to scholars of Law, Criminal Justice and Police Science as well as intelligence analysts and police and security intelligence professionals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A large proportion (over 12 per cent) of international and non-English speaking background (NESB) postgraduate research students enrol in engineering and information technology (IT) programs in Australian universities. They find themselves in an advanced research culture, and are technically and scientifically challenged early in their programs. This is in addition to cultural, social and religious isolation and linguistic barriers they have to contend with. The project team surveyed this cohort at QUT and UWA, on the hypothesis that they face challenges that are more discipline-specific. The results of the survey indicate that existing supervisory frameworks which are limited to linguistic contexts are not fully assisting these students and supervisors to achieve high quality research. The goal of this project is to extend these supervisory frameworks to a holistic model that will address the unique needs and supervisory issues these students face in engineering and IT disciplines. The model will be useable by all other Australian universities.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Custom designed for display on the Cube Installation situated in the new Science and Engineering Centre (SEC) at QUT, the ECOS project is a playful interface that uses real-time weather data to simulate how a five-star energy building operates in climates all over the world. In collaboration with the SEC building managers, the ECOS Project incorporates energy consumption and generation data of the building into an interactive simulation, which is both engaging to users and highly informative, and which invites play and reflection on the roles of green buildings. ECOS focuses on the principle that humans can have both a positive and negative impact on ecosystems with both local and global consequence. The ECOS project draws on the practice of Eco-Visualisation, a term used to encapsulate the important merging of environmental data visualization with the philosophy of sustainability. Holmes (2007) uses the term Eco-Visualisation (EV) to refer to data visualisations that ‘display the real time consumption statistics of key environmental resources for the goal of promoting ecological literacy’. EVs are commonly artifacts of interaction design, information design, interface design and industrial design, but are informed by various intellectual disciplines that have shared interests in sustainability. As a result of surveying a number of projects, Pierce, Odom and Blevis (2008) outline strategies for designing and evaluating effective EVs, including ‘connecting behavior to material impacts of consumption, encouraging playful engagement and exploration with energy, raising public awareness and facilitating discussion, and stimulating critical reflection.’ Consequently, Froehlich (2010) and his colleagues also use the term ‘Eco-feedback technology’ to describe the same field. ‘Green IT’ is another variation which Tomlinson (2010) describes as a ‘field at the juncture of two trends… the growing concern over environmental issues’ and ‘the use of digital tools and techniques for manipulating information.’ The ECOS Project team is guided by these principles, but more importantly, propose an example for how these principles may be achieved. The ECOS Project presents a simplified interface to the very complex domain of thermodynamic and climate modeling. From a mathematical perspective, the simulation can be divided into two models, which interact and compete for balance – the comfort of ECOS’ virtual denizens and the ecological and environmental health of the virtual world. The comfort model is based on the study of psychometrics, and specifically those relating to human comfort. This provides baseline micro-climatic values for what constitutes a comfortable working environment within the QUT SEC buildings. The difference between the ambient outside temperature (as determined by polling the Google Weather API for live weather data) and the internal thermostat of the building (as set by the user) allows us to estimate the energy required to either heat or cool the building. Once the energy requirements can be ascertained, this is then balanced with the ability of the building to produce enough power from green energy sources (solar, wind and gas) to cover its energy requirements. Calculating the relative amount of energy produced by wind and solar can be done by, in the case of solar for example, considering the size of panel and the amount of solar radiation it is receiving at any given time, which in turn can be estimated based on the temperature and conditions returned by the live weather API. Some of these variables can be altered by the user, allowing them to attempt to optimize the health of the building. The variables that can be changed are the budget allocated to green energy sources such as the Solar Panels, Wind Generator and the Air conditioning to control the internal building temperature. These variables influence the energy input and output variables, modeled on the real energy usage statistics drawn from the SEC data provided by the building managers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In recent times, technology has advanced in such a manner that the world can now communicate in means previously never thought possible. Transnational organised crime groups, who have exploited these new technologies as basis for their criminal success, however, have not overlooked this development, growth and globalisation. Law enforcement agencies have been confronted with an unremitting challenge as they endeavour to intercept, monitor and analyse these communications as a means of disrupting the activities of criminal enterprises. The challenge lies in the ability to recognise and change tactics to match an increasingly sophisticated adversary. The use of communication interception technology, such as phone taps or email interception, is a tactic that when used appropriately has the potential to cause serious disruption to criminal enterprises. Despite the research that exists on CIT and TOC, these two bodies of knowledge rarely intersect. This paper builds on current literature, drawing them together to provide a clearer picture of the use of CIT in an enforcement and intelligence capacity. It provides a review of the literature pertaining to TOC, the structure of criminal enterprises and the vulnerability of communication used by these crime groups. Identifying the current contemporary models of policing it reviews intelligence-led policing as the emerging framework for modern policing. Finally, it assesses the literature concerning CIT, its uses within Australia and the limitations and arguments that exist. In doing so, this paper provides practitioners with a clearer picture of the use, barriers and benefits of using CIT in the fight against TOC. It helps to bridge the current gaps in modern policing theory and offers a perspective that can help drive future research.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mesothelioma is a rare malignancy arising from mesothelial cells lining the pleura and peritoneum. Advances in modern technology have allowed the development of array based approaches to the study of disease allowing researchers the opportunity to study many genes or proteins in a high-throughput fashion. This review describes the current knowledge surrounding array based approaches with respect to mesothelioma research. © 2009 by the International Association for the Study of Lung Cancer.