835 resultados para Change in values


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The modern structural diagnosis process is rely on vibration characteristics to assess safer serviceability level of the structure. This paper examines the potential of change in flexibility method to use in damage detection process and two main practical constraints associated with it. The first constraint addressed in this paper is reduction in number of data acquisition points due to limited number of sensors. Results conclude that accuracy of the change in flexibility method is influenced by the number of data acquisition points/sensor locations in real structures. Secondly, the effect of higher modes on damage detection process has been studied. This addresses the difficulty of extracting higher order modal data with available sensors. Four damage indices have been presented to identify their potential of damage detection with respect to different locations and severity of damage. A simply supported beam with two degrees of freedom at each node is considered only for a single damage cases throughout the paper.

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This paper investigates the effects of lane-changing in driver behavior by measuring (i) the induced transient behavior and (ii) the change in driver characteristics, i.e., changes in driver response time and minimum spacing. We find that the transition largely consists of a pre-insertion transition and a relaxation process. These two processes are different but can be reasonably captured with a single model. The findings also suggest that lane-changing induces a regressive effect on driver characteristics: a timid driver (characterized by larger response time and minimum spacing) tends to become less timid and an aggressive driver less aggressive. We offer an extension to Newell’s car-following model to describe this regressive effect and verify it using vehicle trajectory data.

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Pronounced phenotypic shifts in island populations are typically attributed to natural selection, but reconstructing heterogeneity in long-term selective regimes remains a challenge. We examined a scenario of divergence proposed for species colonizing a new environment, involving directional selection with a rapid shift to a new optimum and subsequent stabilization. We provide some of the first empirical evidence for this model of evolution using morphological data from three timescales in an island bird, Zosterops lateralis chlorocephalus. In less than four millennia since separation from its mainland counterpart, a substantial increase in body size has occurred and was probably achieved in fewer than 500 generations after colonization. Over four recent decades, morphological traits have fluctuated in size but showed no significant directional trends, suggesting maintenance of a relatively stable phenotype. Finally, estimates of contemporary selection gradients indicated generally weak directional selection. These results provide a rare description of heterogeneity in long-term natural regimes, and caution that observations of current selection may be of limited value in inferring mechanisms of past adaptation due to a lack of constancy even over short time-frames.

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Environmental and sustainability issues pose challenges for society. Although education is seen as being a contributor to addressing sustainability, teacher education has been slow to act in preparing future teachers to teach sustainability. Recent Australian curriculum documents nominate sustainability as one of three cross-curriculum priorities. In one Australian university course, an Ecological Footprint Calculator tool has been employed to challenge preservice early childhood teachers to consider the sustainability of their lifestyles as a means for engaging them in learning and teaching for sustainability. Students enrolled in an integrated arts and humanities subject voluntarily engaged with the online calculator and shared their findings on an electronic discussion forum. These postings then became the basis of qualitative analysis and discussion. Data categories included reactions and reflections on reasons for the ‘heaviness’ of their footprints , student reactions leading to actions to reduce their footprints, reflections on the implications of the footprint results for future teaching, reactions that considered the need for societal change, and reflections on the integration of sustainability with the visual arts. The power of the tool’s application to stimulate interest in sustainability and education for sustainability more broadly in teacher education is explored.

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Projected increases in atmospheric carbon dioxide concentration ([CO2]) and air temperature associated with future climate change are expected to affect crop development, crop yield, and, consequently, global food supplies. They are also likely to change agricultural production practices, especially those related to agricultural water management and sowing date. The magnitude of these changes and their implications to local production systems are mostly unknown. The objectives of this study were to: (i) simulate the effect of projected climate change on spring wheat (Triticum aestivum L. cv. Lang) yield and water use for the subtropical environment of the Darling Downs, Queensland, Australia; and (ii) investigate the impact of changing sowing date, as an adaptation strategy to future climate change scenarios, on wheat yield and water use. The multimodel climate projections from the IPCC Coupled Model Intercomparison Project (CMIP3) for the period 2030–2070 were used in this study. Climate scenarios included combinations of four changes in air temperature (08C, 18C, 28C, and 38C), three [CO2] levels (380 ppm, 500 ppm, and 600 ppm), and three changes in rainfall (–30%, 0%, and +20%), which were superimposed on observed station data. Crop management scenarios included a combination of six sowing dates (1 May, 10 May, 20 May, 1 June, 10 June, and 20 June) and three irrigation regimes (no irrigation (NI), deficit irrigation (DI), and full irrigation (FI)). Simulations were performed with the model DSSAT4.5, using 50 years of daily weather data.Wefound that: (1) grain yield and water-use efficiency (yield/evapotranspiration) increased linearly with [CO2]; (2) increases in [CO2] had minimal impact on evapotranspiration; (3) yield increased with increasing temperature for the irrigated scenarios (DI and FI), but decreased for the NI scenario; (4) yield increased with earlier sowing dates; and (5) changes in rainfall had a small impact on yield for DI and FI, but a high impact for the NI scenario.

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Cotton growing landscapes in Australia have been dominated by dual-toxin transgenic Bt varieties since 2004. The cotton crop has thus effectively become a sink for the main target pest, Helicoverpa armigera. Theory predicts that there should be strong selection on female moths to avoid laying on such plants. We assessed oviposition, collected from two cotton-growing regions, by female moths when given a choice of tobacco, cotton and cabbage. Earlier work in the 1980s and 1990s on populations from the same geographic locations indicated these hosts were on average ranked as high, mid and low preference plants, respectively, and that host rankings had a heritable component. In the present study, we found no change in the relative ranking of hosts by females, with most eggs being laid on tobacco, then cotton and least on cabbage. As in earlier work, some females laid most eggs on cotton and aspects of oviposition behaviour had a heritable component. Certainly, cotton is not avoided as a host, and the implications of these finding for managing resistance to Bt cotton are discussed.

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This paper plots the recent changes in the uses of public space in Hanoi, Vietnam. It is argued that the economic and social changes in contemporary Vietnam have paved the way for a dramatic transformation in the ways in which streets, pavements and markets are experienced and imagined by the populace. The efflorescence of individual mobility, street-trading and public crowding around certain popular events has led to the emergence of a distinct public sphere, one which is not immune from state control and censure but which is a flagrant rebuttal of the state's appeal. The immediate struggles over space herald a new discursive arena for the contest over Vietnamese national imagery as represented in cultural heritage and public space, memorials and state-controlled events which the public are rapidly deserting. The paper concludes by suggesting that the everyday cultural practices that have created a bustling streetlife in urban Vietnam will inevitably provide the vitality and spectacle for the destabilisation of state control in a struggle for meanings in public space.

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This paper examines the innovativeness of nascent and young entrepreneurial firms in Australia. Findings of interest in this paper include: • The vast majority of new ventures offer some degree of innovation in some aspect of their business, be it the product, the process, their market selection or their marketing approach. • With close to 75 per cent claiming they do more than taking mere imitations to the market, novelty in the product/service is the type of innovation most commonly offered by start-up firms. • The innovativeness of start-ups varies by industry. Construction start-ups stand out as particularly low in innovation across all indicators, while Manufacturing stands out the most in the positive direction. • Team start-ups other than spouse teams have higher novelty, as do ventures started by founders with prior start-up experience. • There is no association between the founders’ level of education and the novelty of the ventures they (try to) create.

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This study models the joint production of desirable and undesirable output production (that is, CO2 emissions) of airlines. The Malmquist-Luenberger productivity index is employed to measure productivity growth when undesirable output production is regulated and unregulated. The results show that pollution abatement activities of airlines lowers productivity growth which suggests the traditional approach of measuring productivity growth, which ignores CO2 emissions, overstate "true" productivity growth.

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We live in a time of change, of rapid change in some cases. Regardless of where we live as Indigenous peoples we see this, feel this, know this and understand this. Yet how do we manage this? At times Indigenous knowledge and Western knowledge are aligned and at other times diametrically opposed. This is also the case when examining how Indigenous knowledges are viewed, accessed and used even when politicians, governments and institutions are searching for answers and solutions for Indigenous people and for broader Australian society. Sometimes we have witnessed Indigenous knowledges too far down the back, at the bottom of the list and even disregarded. In some cases Indigenous peoples and our knowledges have been positioned as the victims of modernity. Imagine if we could draw on the strength of Indigenous knowledges as the driving force to change direction or for change. We can do this. This paper will explore some of the ways we might do this and bring about an improved society for all peoples.

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In 2012, Australia introduced a new National Quality Framework, comprising enhanced quality expectations for early childhood education and care services, two national learning frameworks and a new Assessment and Rating System spanning child care centres, kindergartens and preschools, family day care and outside school hours care. This is the linchpin in a series of education reforms designed to support increased access to higher quality early childhood education and care (ECEC) and successful transition to school. As with any policy change, success in real terms relies upon building shared understanding and the capacity of educators to apply new knowledge and to support change and improved practice within their service. With this in mind, a collaborative research project investigated the efficacy of a new approach to professional learning in ECEC: the professional conversation. This paper reports on the trial and evaluation of a series of professional conversations to support implementation of one element of the NQF, the Early Years Learning Framework (DEEWR,2009), and their capacity to promote collaborative reflective practice, shared understanding, and improved practice in ECEC. Set against the backdrop of the NQF, this paper details the professional conversation approach, key challenges and critical success factors, and the learning outcomes for conversation participants. Findings support the efficacy of this approach to professional learning in ECEC, and its capacity to support policy reform and practice change in ECEC.

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Does the current global political economic framework, or more specifically, the cost-price squeeze associated with primary production, restrict the choices of Australian cattle graziers in moving to more sustainable practices? It has often been argued by primary producers and academics, alike, that current terms of trade have resulted in reduced profitability at the property level, and as such, have made it difficult for landholders to shift to practices which are environmentally sustainable. Whilst there is mounting evidence that this is case, there is also evidence that some graziers have been able to adapt to the prevailing market conditions through an ideological as well as ‘practice’ shift. Findings from qualitative research in Central Queensland, Australia has highlighted how ‘cell grazing’ departs from the traditional or conventional aspects of grazing which can be described as productivist, to an approach closely approximating Lang and Heasman’s (2004) ‘ecologically integrated paradigm’. It is argued that cell grazing is, at present, a marginal activity that requires an ideological and cultural shift, as well as an investment in new infrastructure, however, current cell grazing activities may also demonstrate that beef grazing has the potential to be both economically and environmentally sustainable.

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In the next half-century, Australia's population of people aged over 65 is set to almost double. As a consequence, there is an urgent need in both Australia and New Zealand, where older people value their independence, for housing that fully supports them in their own suburban homes. With only a handful of models in place, Mark Taylor, Professor of Architecture at the University of Newcastle, Australia, and Laurie Buys, a Professor in the School of Design at Queensland University of Technology in Brisbane, have tracked down some promising precedents for suburban living in adapted homes and within community-based shared housing.

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The effect of a change of tillage and crop residue management practice on the chemical and micro-biological properties of a cereal-producing red duplex soil was investigated by superimposing each of three management practices (CC: conventional cultivation, stubble burnt, crop conventionally sown; DD: direct-drilling, stubble retained, no cultivation, crop direct-drilled; SI: stubble incorporated with a single cultivation, crop conventionally sown), for a 3-year period on plots previously managed with each of the same three practices for 14 years. A change from DD to CC or SI practice resulted in a significant decline, in the top 0-5 cm of soil, in organic C, total N, electrical conductivity, NH4-N, NO3-N, soil moisture holding capacity, microbial biomass and CO2 respiration as well as a decline in the microbial quotient (the ratio of microbial biomass C to organic C; P <0.05). In contrast, a change from SI to DD or CC practice or a change from CC to DD or SI practice had only negligible impact on soil chemical properties (P >0.05). However, there was a significant increase in microbial biomass and the microbial quotient in the top 0-5 cm of soil following the change from CC to DD or SI practice and with the change from SI to DD practice (P <0.05). Analysis of ester-linked fatty acid methyl esters (EL-FAMEs) extracted from the 0- to 5-cm and 5- to 10-cm layers of the soils of the various treatments detected changes in the FAME profiles following a change in tillage practice. A change from DD practice to SI or CC practice was associated with a significant decline in the ratio of fungal to bacterial fatty acids in the 0- to 5-cm soil (P <0.05). The results show that a change in tillage practice, particularly the cultivation of a previously minimum-tilled (direct-drilled) soil, will result in significant changes in soil chemical and microbiological properties within a 3-year period. They also show that soil microbiological properties are sensitive indicators of a change in tillage practice.