980 resultados para link capacity


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Australian manufacturers recently developed a new mono-symmetric cold-formed steel hollow flange channel section known as LiteSteel Beam. The innovative LSB sections with rectangular flanges are currently being used as floor joists and bearers in buildings. In order to assess their behaviour and section moment capacity including the presence of any inelastic reserve bending capacity, 20 section moment capacity tests were conducted in this study. Test results were compared with the section moment capacities predicted by the steel design codes. Although the current cold-formed steel design rules generally limit the section moment capacities to their first yield moments, test results showed that inelastic reserve bending capacity was present in the compact and non-compact LSB sections. The results have shown that suitable modifications to the current design rules are needed to allow the inclusion of available inelastic bending capacities of LSBs in design.

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Airports represent the epitome of complex systems with multiple stakeholders, multiple jurisdictions and complex interactions between many actors. The large number of existing models that capture different aspects of the airport are a testament to this. However, these existing models do not consider in a systematic sense modelling requirements nor how stakeholders such as airport operators or airlines would make use of these models. This can detrimentally impact on the verification and validation of models and makes the development of extensible and reusable modelling tools difficult. This paper develops from the Concept of Operations (CONOPS) framework a methodology to help structure the review and development of modelling capabilities and usage scenarios. The method is applied to the review of existing airport terminal passenger models. It is found that existing models can be broadly categorised according to four usage scenarios: capacity planning, operational planning and design, security policy and planning, and airport performance review. The models, the performance metrics that they evaluate and their usage scenarios are discussed. It is found that capacity and operational planning models predominantly focus on performance metrics such as waiting time, service time and congestion whereas performance review models attempt to link those to passenger satisfaction outcomes. Security policy models on the other hand focus on probabilistic risk assessment. However, there is an emerging focus on the need to be able to capture trade-offs between multiple criteria such as security and processing time. Based on the CONOPS framework and literature findings, guidance is provided for the development of future airport terminal models.

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Multi-user single antenna multiple-input multiple-output orthogonal frequency division multiplexing (MUSA-MIMO-OFDM) is a promising technology to improve the spectrum efficiency of fixed wireless broadband access systems in rural areas. This letter investigates the capacity of MUSA-MIMO-OFDM uplink channel by theoretical, simulation, and empirical approaches considering up to six users. We propose an empirical capacity formula suitable for rural areas. Characteristics of channel capacity temporal variations and their relationship with the wind speed, observed in a rural area, are also presented in this letter.

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In this conceptual article, we extend earlier work on Open Innovation and Absorptive Capacity. We suggest that the literature on Absorptive Capacity does not place sufficient emphasis on distributed knowledge and learning or on the application of innovative knowledge. To accomplish physical transformations, organisations need specific Innovative Capacities that extend beyond knowledge management. Accessive Capacity is the ability to collect, sort and analyse knowledge from both internal and external sources. Adaptive Capacity is needed to ensure that new pieces of equipment are suitable for the organisation's own purposes even though they may have been originally developed for other uses. Integrative Capacity makes it possible for a new or modified piece of equipment to be fitted into an existing production process with a minimum of inessential and expensive adjustment elsewhere in the process. These Innovative Capacities are controlled and coordinated by Innovative Management Capacity, a higher-order dynamic capability.

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Designing practical rules for controlling invasive species is a challenging task for managers, particularly when species are long-lived, have complex life cycles and high dispersal capacities. Previous findings derived from plant matrix population analyses suggest that effective control of long-lived invaders may be achieved by focusing on killing adult plants. However, the cost-effectiveness of managing different life stages has not been evaluated. We illustrate the benefits of integrating matrix population models with decision theory to undertake this evaluation, using empirical data from the largest infestation of mesquite (Leguminosae: Prosopis spp) within Australia. We include in our model the mesquite life cycle, different dispersal rates and control actions that target individuals at different life stages with varying costs, depending on the intensity of control effort. We then use stochastic dynamic programming to derive cost-effective control strategies that minimize the cost of controlling the core infestation locally below a density threshold and the future cost of control arising from infestation of adjacent areas via seed dispersal. Through sensitivity analysis, we show that four robust management rules guide the allocation of resources between mesquite life stages for this infestation: (i) When there is no seed dispersal, no action is required until density of adults exceeds the control threshold and then only control of adults is needed; (ii) when there is seed dispersal, control strategy is dependent on knowledge of the density of adults and large juveniles (LJ) and broad categories of dispersal rates only; (iii) if density of adults is higher than density of LJ, controlling adults is most cost-effective; (iv) alternatively, if density of LJ is equal or higher than density of adults, management efforts should be spread between adults, large and to a lesser extent small juveniles, but never saplings. Synthesis and applications.In this study, we show that simple rules can be found for managing invasive plants with complex life cycles and high dispersal rates when population models are combined with decision theory. In the case of our mesquite population, focussing effort on controlling adults is not always the most cost-effective way to meet our management objective.

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School reform is a matter of both redistributive social justice and recognitive social justice. Following Fraser (Justice interruptus: critical reflections on the “postsocialist” condition. Routledge, New York, 1997), we begin from a philosophical and political commitment to the more equitable redistribution of knowledge, credentials, competence, and capacity to children of low socioeconomic, cultural, and linguistic minority and Indigenous communities whose access, achievement, and participation historically have “lagged” behind system norms and benchmarks set by middle class and dominant culture communities. At the same time, we argue that the recognition of these students and their communities’ lifeworlds, knowledges, and experiences in the curriculum, in classroom teaching, and learning is both a means and an end: a means toward improved achievement measured conventionally and a goal for reform and alteration of mainstream curriculum knowledge and what is made to count in the school as valued cultural knowledge and practice. The work that we report here was based on an ongoing 4-year project where a team of university teacher educators/researchers have partnered with school leadership and staff to build relationships within community. The purpose has been to study whether and how engagement with new digital arts and multimodal literacies could have effects on students “conventional” print literacy achievement and, secondly, to study whether and how the overall performance of a school could be generated through a focus on professional conversations and partnerships in curriculum and instruction – rather than the top-down implementation of a predetermined pedagogical scheme, package, or approach.

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Recent studies suggest that meta-evaluation can be valuable in developing new approaches to evaluation, building evaluation capacities, and enhancing organizational learning. These new extensions of the concept of meta-evaluation are significant, given the growing emphasis on improving the quality and effectiveness of evaluation practices in the South Asian region. Following a review of the literature, this paper presents a case study of the use of concurrent meta-evaluation in the four-year project Assessing Communication for Social Change which developed and trialled a participatory impact assessment methodology in collaboration with a development communication Non-government organization (NGO) in Nepal. Key objectives of the meta-evaluation included to: continuously develop, adapt and improve the impact assessment methodology, Monitoring and Evaluation (M&E) systems and process and other project activities; identify impacts of the project; and build capacities in critical reflection and review. Our analysis indicates that this meta-evaluation was essential to understanding various constraints related to the organizational context that affected the success of the project and the development of improved M&E systems and capacities within the NGO. We identified several limitations of our meta-evaluation methods, which were balanced by the strengths of other methods. Our case study suggests that as well as assessing the quality, credibility and value of evaluation practices, meta-evaluations need to focus on important contextual issues that can have significant impacts on the outcomes of participatory evaluation projects. They include hierarchical organizational cultures, communication barriers, power/knowledge relations, and the time and resources available. Meta-evaluations also need to consider wider issues such as the sustainability of evaluation systems and approaches.

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The Teaching Teachers for the Future (TTF) project is a unique nationally significant project funded by the Australian Government through the Department of Employment, Education and Workplace Relations (DEEWR, Au$8.8 million) and the Information and Communication Technology Innovation Fund (ICTIF). This 2011-2012 project has ambitiously attempted to build the ICT education (ICTE) capacity of the next generation of Australian teachers through its focus on pre-service teachers, teacher educators and the new Australian Curriculum. This paper will provide an overview of the project including a description of its genesis in a changing educational and political landscape, its structure and operations, its grounding in contemporary theory, the research opportunities it has engendered and its tangible outcomes.

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Divalent cobalt ions (Co2+) have been shown to possess the capacity to induce angiogenesis by activating hypoxia inducible factor-1α (HIF-1α) and subsequently inducing the production of vascular endothelial growth factor (VEGF). However, there are few reports about Co-containing biomaterials for inducing in vitro angiogenesis. The aim of the present work was to prepare Co-containing β-tricalcium phosphate (Co-TCP) ceramics with different contents of calcium substituted by cobalt (0, 2, 5 mol%) and to investigate the effect of Co substitution on their physicochemical and biological properties. Co-TCP powders were synthesized by a chemistry precipitation method and Co-TCP ceramics were prepared by sintering the powder compacts. The effect of Co substitution on phase transition and the sintering property of the β-TCP ceramics was investigated. The proliferation and VEGF expression of human bone marrow mesenchymal stem cells (HBMSCs) cultured with both powder extracts and ceramic discs of Co-TCP was further evaluated. The in vitro angiogenesis was evaluated by the tube-like structure formation of human umbilical vein endothelial cells (HUVECs) cultured on ECMatrix™ in the presence of powder extracts. The results showed that Co substitution suppressed the phase transition from β- to α-TCP. Both the powder extracts and ceramic discs of Co-TCP had generally good cytocompatibility to support HBMSC growth. Importantly, the incorporation of Co into β-TCP greatly stimulated VEGF expression of HBMSCs and Co-TCP showed a significant enhancement of network structure formation of HUVECs compared with pure TCP. Our results suggested that the incorporation of Co into bioceramics is a potential viable way to enhance angiogenic properties of biomaterials. Co-TCP bioceramics may be used for bone tissue regeneration with improved angiogenic capacity.

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This paper describes a capacity building process undertaken within the HIV/AIDS prevention project of the Adventist Development and Relief Agency (ADRA) in the Solomon Islands. ADRA HIV/AIDS has recently reoriented its project structure, moving beyond its awareness raising approach to incorporate health promotion frameworks, theories, strategies and assumptions. These have been used to inform project practice in project planning, delivery and evaluation. This paper shares what has worked and not worked in the capacity building process, including a project evaluation of the initial HIV/AIDS awareness raising project and the application of a number of capacity building strategies, including utilising a volunteer Australian Youth Ambassador for Development (AYAD) funded by the Australian Agency for International Development (AusAID). Existing and new projects are outlined. The underlying theme is that any capacity building exercise must include structural support (e.g. management, national frameworks) to ensure the incorporation of new initiatives and approaches. With time this enables ownership by counterparts and external partnerships to develop. The presence of an AYAD volunteer has been an effective strategy to achieve this. Reflections from the evaluators, the AYAD volunteer and the HIV/AIDS team are included.