182 resultados para behaviour change technique


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The aim of the present study was to investigate the role of deformation temperature on the active deformation mechanisms in a 0.6C-18Mn-1.5Al (wt%) TWIP steel. The tensile testing was performed at different temperatures, ranging from ambient to 400°C at a constant strain rate of 10-3 S-1. The microstructure characterization was carried out using a scanning electron microscopy. The deformation temperature revealed a significant effect on the active deformation mechanisms (i.e. slip versus twinning), resulting in different microstructure evolution and mechanical properties. At the room temperature, the mechanical twinning was the dominant deformation mechanism, enhancing both the strength and ductility. Dynamic strain aging (DSA) effect was observed at different deformation temperatures, though it was more pronounced at higher temperatures. The volume fraction of deformation twins significantly reduced with an increase in the deformation temperature, deteriorating the mechanical behavior. There was a transition temperature (~300°C), above which the mechanical twinning was hardly observed in the microstructure even at fracture, resulting in low ductility and strength. The current observation can be explained through the change in the stacking fault energy with the deformation temperature. © (2014) Trans Tech Publications, Switzerland.

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Microcompression tests were performed on monolithic Cu and Fe thin films and a Cu/Fe multilayer that had each individual layer of 200 nm thick, to understand the mechanical behaviour of multiple nanolayers. The micron-sized pillars were prepared by focused-ion beam (FIB) technique and compressed with a flat punch in a nanoindenter. The flow curves of the monolithic Cu and Fe thin films and Cu/Fe multilayer were extracted from the microcompression tests. The monolithic Cu thin film bulges in the top region of the pillar, while the Fe thin film cracks due to its columnar grain structure. For the Cu/Fe multilayer, the ductile Cu layers accommodate the majority of plastic deformation upon compression, while cracking in the Fe layers leads to the failure of the multilayer. Finite element models of microcompression tests were also developed to provide insights into the deformation behaviours of the multilayer and monolithic thin films. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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Mature female southern elephant seals (Mirounga leonina) come ashore only in October to breed and in January to moult, spending the rest of the year foraging at sea. Mature females may lose as much as 50% of their body mass, mostly in lipid stores, during the breeding season due to fasting and lactation. When departing to sea, post-breeding females are negatively buoyant, and the relative change in body condition (i.e. density) during the foraging trip has previously been assessed by monitoring the descent rate during drift dives. However, relatively few drift dives are performed, resulting in low resolution of the temporal reconstruction of body condition change. In this study, six post-breeding females were equipped with time-depth recorders and accelerometers to investigate whether changes in active swimming effort and speed could be used as an alternative method of monitoring density variations throughout the foraging trip. In addition, we assessed the consequences of density change on the swimming efforts of individuals while diving and investigated the effects on dive duration. Both descent swimming speed and ascent swimming effort were found to be strongly correlated to descent rate during drift dives, enabling the fine-scale monitoring of seal density change over the whole trip. Negatively buoyant seals minimized swimming effort during descents, gliding down at slower speeds, and reduced their ascent swimming effort to maintain a nearly constant swimming speed as their buoyancy increased. One per cent of seal density variation over time was found to induce a 20% variation in swimming effort during dives with direct consequences on dive duration.

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'This is essential reading for social marketing practitioners, researchers and students. the book describes a comprehensive range of behavior change theories of relevance to social marketing and is complemented with illustrative case ...

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Remote sensing is a useful tool for detecting change over time.We introduce a hybrid change-detection method for forest and protected-area vegetation and demonstrate its use with two satellite images of Golestan National Park in northern Iran (1998 and 2010). We report on the advantages and disadvantages of the hybrid method relative to the standard change-detection method. In the proposed hybrid algorithm, the change vector analysis technique was used to determine changes in vegetation. Following this, we used postclassification comparison to determine the nature of the changes observed and their accuracy and to evaluate the effects of different parameters on the performance of the proposed method. We determined 85% accuracy for the proposed hybrid change-detection method, thus demonstrating a method for discovering and assessing environmental threats to natural treasures. © 2014 Society of Photo-Optical Instrumentation Engineers.

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BACKGROUND: There is little empirical evidence of the impact of transition from primary to secondary school on obesity-related risk behaviour. The purpose of this study was to examine the effect of a change of school system on physical activity (PA) and sedentary behaviour in pre-early adolescents. METHODS: Fifteen schools in Victoria, Australia were recruited at random from the bottom two strata of a five level socio-economic scale. In nine schools, students in year 6 primary school transitioned to a different school for year 7 secondary school, while in six schools (combined primary-secondary), students remained in the same school environment from year 6 to year 7. Time 1 (T1) measures were collected from students (N=245) in year 6 (age 11-13). Time 2 (T2) data were collected from 243 (99%) of the original student cohort when in year 7. PA and sedentary behaviour data were collected objectively (via ActiGraph accelerometer) and subjectively (via child self-report recall questionnaire). School environment data were collected via school staff survey. Change of behaviour analyses were conducted longitudinally i) for all students and ii) by change/no change of school. Mixed model regression analysis tested for behavioural interaction effects of changing/not changing school. RESULTS: Sixty-three percent (N=152) changed schools from T1 to T2. Across all students we observed declines in average daily moderate to vigorous physical activity (MVPA) (-4 min) and light PA (-23 min), and increases in average daily sedentary behaviour (16 min), weekday leisure screen time (17 min) and weekday homework screen time (25 min), all P<0.05. Compared to students who remained in the same school environment, students who changed school reported a greater reduction in PA intensity at recess and lunch, less likelihood to cycle to/from school, greater increase in weekday (41 mins) and weekend (45 mins) leisure screen time (P<0.05) and greater encouragement to participate in sport. School staff surveys identified that sport participation encouragement was greater in primary and combined primary-secondary than secondary schools (P<0.05). CONCLUSION: Transitioning from primary to secondary school negatively impacts on children's PA and sedentary behaviour, and has further compounding effects on behaviour type by changing school environments.

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A laboratory-based transmission X-ray diffraction technique was developed to measure elastic lattice strains parallel to the loading direction during in situ tensile deformation. High-quality transmission X-ray diffraction data were acquired in a time frame suitable for in situ loading experiments by application of a polycapillary X-ray optic with a conventional laboratory Cu X-ray source. Based on the measurement of two standard reference materials [lanthanum hexaboride (NIST SRM 660b) and silicon (NIST SRM 640c)], precise instrumental alignment and calibration of the transmission diffraction geometry were realized. These results were also confirmed by the equivalent data acquired using the standard Bragg-Brentano measurement geometry. An empirical Caglioti function was employed to describe the instrumental broadening, while an axis of rotation correction was used to measure and correct the specimen displacement from the centre of the goniometer axis. For precise Bragg peak position and hkil intensity information, a line profile fitting methodology was implemented, with Pawley refinement used to measure the sample reference lattice spacings (d o (hkil)). It is shown that the relatively large X-ray probe size available (7 × 714mm) provides a relatively straightforward approach for improving the grain statistics for the study of metal alloys, where grain sizes in excess of 114μm can become problematic for synchrotron-based measurements. This new laboratory-based capability was applied to study the lattice strain evolution during the elastic-plastic transition in extruded and rolled magnesium alloys. A strain resolution of 2 × 10-4 at relatively low 2θ angles (20-65° 2θ) was achieved for the in situ tensile deformation studies. In situ measurement of the elastic lattice strain accommodation with applied stress in the magnesium alloys indicated the activation of dislocation slip and twin deformation mechanisms. Furthermore, measurement of the relative change in the intensity of 0002 and 10 3 was used to quantify {10 2} 011 tensile twin onset and growth with applied load.

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Recently, there has been growing recognition that fish harvesting practices can have important impacts on the phenotypic distributions and diversity of natural populations through a phenomenon known as fisheries-induced evolution. Here we experimentally show that two common recreational angling techniques (active crank baits versus passive soft plastics) differentially target wild largemouth bass (Micropterus salmoides) and rock bass (Ambloplites rupestris) based on variation in their behavioural tendencies. Fish were first angled in the wild using both techniques and then brought back to the laboratory and tested for individual-level differences in common estimates of personality (refuge emergence, flight-initiation-distance, latency-to-recapture and with a net, and general activity) in an in-lake experimental arena. We found that different angling techniques appear to selectively target these species based on their boldness (as characterized by refuge emergence, a standard measure of boldness in fishes) but not other assays of personality. We also observed that body size was independently a significant predictor of personality in both species, though this varied between traits and species. Our results suggest a context-dependency for vulnerability to capture relative to behaviour in these fish species. Ascertaining the selective pressures angling practices exert on natural populations is an important area of fisheries research with significant implications for ecology, evolution, and resource management.

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Organisational culture is a complex and heavily contested concept. Not only is it difficult to define what organisational culture is, but it is also very difficult to analyse how it guides and constrains behaviour, and whether and how organisational cultures change. The central argument of this article is that organisational networks can effect cultural change and that the terms ‘structural’ and ‘relational’, which are commonly used to conceptualise the properties of networks, may also provide a useful conceptual framework for understanding cultural change. While there has been some attention directed to the effects of organisational culture for networks, there has been very little attention placed on the potential for networks to shape organisational culture. Based on a detailed qualitative study of networks in the field of ‘high’ policing in Australia, the article draws on interviews with senior members of police and security agencies to explore organisational culture and cultural change. The article puts forward a network perspective on cultural change and aims to advance our knowledge of how security nodes can experience cultural change as they work together in and through networks.

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During the breeding season, seabirds are central place foragers and have to adapt their foraging behaviour in response to environmental variation to maximize efficiency and reproductive output. Due to its small size and swimming mode of transport, the little penguin (Eudyptula minor) is expected to be greatly susceptible to such fluctuations. The links between local-, meso- and macro-scale environmental conditions and inter-annual variation in foraging behaviour and reproductive performance of little penguins were investigated during three consecutive breeding seasons at two colonies in south-eastern Australia marked by contrasting oceanographic conditions. At a local scale, foraging effort was correlated positively with wind direction and negatively with wave height. At a regional scale, foraging effort of individuals from both colonies was negatively correlated with higher sea surface temperature (SST) off the Bonney Coast in the previous Austral summer, suggesting a weaker Bonney Upwelling event and a cascade of effects throughout the Bass Strait region. At a larger scale, the El Niño Southern Oscillation was also found to correlate with foraging behaviour, with lower foraging effort being observed during La Niña event. Although individuals increased their foraging effort during years with poorer conditions, they were not able to maintain high breeding success. In addition, peak egg-laying was found to coincide with a decrease in local SST and a peak of sea surface chlorophyll-a concentration. In conclusion, these results highlight how different environmental conditions could influence foraging behaviour and ultimately reproductive success of little penguins. It also showed that under certain circumstances, these individual strategies were not sufficient to cope with environmental variability.

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Phenotypic variation and individual experience can create behavioural and/or dietary variation within a population. This may reduce intra-specific competition, creating a buffer to environmental change. This study examined how intrinsic variation affects foraging behaviour of Australian fur seals. Foraging movements of 29 female Australian fur seals were recorded using FastLoc GPS and dive behaviour recorders. For each individual, body mass, flipper length and axis length were recorded, a tooth was sampled to determine age, and milk was collected for diet analysis. Clustering of fatty acid dietary analysis revealed 5 distinct groups in the population. Behaviour was described using 19 indices, which were then reduced to 7 principal components (>80% of the behavioural variation). Bayesian mixed effect models were developed to describe the relationship between these components and intrinsic variation. No association was found between diet and age or body shape; however, age had a negative relationship with component 1 (27% of variation). Older females spent less time at-sea and foraged nearer to the colony. Age had an effect on component 5 (7% of variation), which represented haul-outs and dive depth; older females made fewer visits to haul-out sites and dived deeper to the benthos. This suggests that as animals age they are able to utilise prior knowledge to exploit nearby foraging sites that younger animals are either unaware of, or have yet to gain the experience required to efficiently utilise. Mass had a negative effect on components representing the directedness of a foraging trip, suggesting heavier individuals were more likely to travel directly to a foraging site.

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 A re-conceptualisation of the risk process was an outcome of this research, from which a positioning theory of crime was developed to explain more comprehensively the causal mechanisms by which risk effects are exerted and conduce to offending behaviour.

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© 2015 The Association for the Study of Animal Behaviour. Broad sense repeatability, which refers to the extent to which individual differences in trait scores are maintained over time, is of increasing interest to researchers studying behavioural or physiological traits. Broad sense repeatability is most often inferred from the statistic R (the intraclass correlation, or narrow sense repeatability). However, R ignores change over time, despite the inherent longitudinal nature of the data (repeated measures over time). Here, we begin by showing that most studies ignore time-related change when estimating broad sense repeatability, and estimate R with low statistical power. Given this problem, we (1) outline how and why ignoring time-related change in scores (that occurs for whatever reason) can seriously affect estimates of the broad sense repeatability of behavioural or physiological traits, (2) discuss conditions in which various indices of R can or cannot provide reliable estimates of broad sense repeatability, and (3) provide suggestions for experimental designs for future studies. Finally, given that we already have abundant evidence that many labile traits are 'repeatable' in that broad sense (i.e. R>. 0), we suggest a shift in focus towards obtaining robust estimates of the repeatability of behavioural and physiological traits. Given how labile these traits are, this will require greater experimental (and/or statistical) control and larger sample sizes in order to detect and quantify change over time (if present).

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A phase change material (PCM) from a mixture of plant oils was incorporated into electrospun poly(vinyl alcohol) (PVA) nanofibers using an emulsion electrospinning technique. Effects of PCM and PVA content in the emulsions on nanofiber morphology, heat properties, and phase change stability were examined. Higher PCM loadings in the nanofibers led to increased fiber diameter, gouged fiber surfaces, and higher heat enthalpies. The fibers maintained their morphological integrity even if the PCM melted. They showed reliable heat-regulating performance which can undergo at least 100 cycles of phase change. Such PCM fibers may be used for the development of thermoregulating fabrics or in passive heat storage devices.

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This manual has been written to guide the assessment of change in each of the programs currently offered by the Offending Behaviour Programs Branch, Corrections Victoria. The aim is to identify a set of outcome measures that can be used to both evaluate the overall effectiveness of a program as well as inform judgements about the changes that individual offenders have made over the course of their program participation. Accordingly, the focus is on the assessment of short-term change and not on other areas of assessment, such as assessing changes in risk of reoffending, identifying intervention needs, or establishing an offender’s suitability or eligibility to take part in a program.