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Hydro-meteorological drivers and sources of suspended sediment flux in the proglacial zone of the retreating Castle Creek glacier, Cariboo Mountains, British Columbia, Canada
Glaciers are major agents of erosion that increase sediment load to the downstream fluvial system. The Castle Creek Glacier, British Columbia, Canada, has retreated ~1.0 km in the past 70 years. Suspended sediment concentration (SSC) and streamflow (Q) were monitored independently at five sites within its pro-glacial zone over a 60 day period from July to September 2011, representing part of the ablation season. Meteorological data were collected from two automatic weather stations proximal to the glacier. The time-series were divided into hydrologic days and the shape and magnitude of the SSC response to hydro-meteorological conditions (‘cold and wet’, ‘hot and dry’, ‘warm and damp’, and ‘storm’) were categorized using principal component analysis (PCA) and cluster analysis (CA). Suspended sediment load (SSL) was computed and summarized for the categories. The distribution of monitoring sites and results of the multivariate statistical analyses describe the temporal and spatial variability of suspended sediment flux and the relative importance of glacial and para-glacial sediment sources in the pro-glacial zone. During the 2011 study period, ~ 60% of the total SSL was derived from the glacial stream and sediment deposits proximal to the terminus of the glacier; during ‘storm’ events, that contribution dropped to ~40% as the contribution from diffuse and point sources of sediment throughout the pro-glacial zone and within the meltwater channels increased. While ‘storm’ events accounted for just 3% of the study period, SSL was ~600% higher than the average over the monitoring period, and ~20% of the total SSL was generated in that time. Determining how hydro-meteorological conditions and sediment sources control sediment fluxes will assist attempts to predict how pro-glacial zones respond to future climate changes. Copyright © 2015 John Wiley & Sons, Ltd
Physical activity and play behaviours in children and young people with intellectual disabilities: A cross-sectional observational study
The benefits of physical activity and active play for children and young people are well established. However, there is a lack of physical activity research involving children and young people with intellectual disabilities. This study investigated habitual physical activity and recess play behaviour in 70 5- to 15-year-old participants with intellectual disabilities using objective methods (accelerometers) and systematic observation techniques. Results showed that few children were active enough to benefit their physical health (23% of the cohort). No differences in habitual physical activity, sedentary behaviour, or recess play behaviours were observed between boys and girls. Participants spent most of their recess time alone or playing in small groups, with no participants engaging in large group play. Older participants spent more recess time playing in small groups rather than playing alone and participants with Autistic Spectrum Disorder spent more time engaged in active pursuits and less time standing than non-Autism Spectrum Disorder participants. Positive correlations were observed between time spent alone and physical activity. These findings contrast with those typically observed in a mainstream school setting. In conclusion, interventions designed from formative research are needed to promote physical activity within this population. Implications for school psychologists are discussed
An evaluation of persistent meteorological drought using a homogeneous Island of Ireland precipitation network
This paper investigates the spatial and temporal properties of persistent meteorological droughts using the homogeneous Island of Ireland Precipitation (IIP) network. Relative to a 1961-1990 baseline period it is shown that the longest observed run of below average precipitation since the 1850s lasted up to 5 years (10 half-year seasons) at sites in southeast and east Ireland, or 3 years across the network as a whole. Dry- and wet-spell length distributions were represented by a first-order Markov model which yields realistic runs of below average rainfall for individual sites and IIP series. This model shows that there is relatively high likelihood (p=0.125) of a 5 year dry-spell at Dublin, and that near unbroken dry runs of 10 years or more are conceivable. We suggest that the IIP network and attendant rainfall deficit modelling provide credible data for stress testing water supply and drought plans under extreme conditions
Performance Analysis of TCP Traffic and Its Influence on ONU’s Energy Saving in Energy Efficient TDM-PON
The majority of the traffic over the Internet is TCP based, which is very sensitive to packet loss and delay. Existing research efforts in TDM-Passive Optical Networks (TDM-PONs) mostly evaluate energy saving and traffic delay performances under different energy saving solutions. However, to the best of our knowledge, how energy saving mechanisms could affect TCP traffic performance in TDM-PONs has hardly been studied. In this paper, by means of our state-of-art OPNET Modular based TDM-PON simulator, we evaluate TCP traffic delay, throughput, and Optical Network Unit (ONU) energy consumption performances in a TDM-PON where energy saving mechanisms are employed in ONUs. Here, we study the performances under commonly used energy saving mechanisms defined in standards for TDM-PONs: cyclic sleep and doze mode. In cyclic sleep mode, we evaluate the performances under two well-known sleep interval length deciding algorithms (i.e. fixed sleep interval (FSI) and exponential sleep interval deciding (ESID)) that an OLT uses to decide sleep interval lengths for an ONU. Findings in this paper put forward the strong relationship among TCP traffic delay, throughput and ONU energy consumption under different sleep interval lengths. Moreover, we reveal that under high TCP traffic, both FSI and ESID will end up showing similar delay, energy and throughput performance. Our findings also show that doze mode can offer better TCP throughput and delay performance at the price of consuming more energy than cyclic sleep mode. In addition, our results provide a glimpse on understanding at what point doze mode becomes futile in improving energy saving of an ONU under TCP traffic. Furthermore, in this paper, we highlight important research issues that should be studied in future research to maximize energy saving in TDM-PONs while meeting traffic Quality of Service requirements
Health needs assessment of young offenders in the youth justice system on Merseyside
Liverpool Health Observatory (LPHO) was commissioned to undertake a health needs assessment (HNA) for young offenders across the youth justice system on Merseyside. The HNA covers Liverpool, , Knowsley, Sefton, St Helens, Wirral and Halton. It includes a detailed description of the young offender population, both nationally and on Merseyside, and a brief review of relevant literature, as well as interviews with young people and health care staff, in both secure and community setting
Identifying the causal mechanisms of the quiet eye
Scientists who have examined the gaze strategies employed by athletes have determined that longer quiet eye (QE) durations (QED) are characteristic of skilled compared to less-skilled performers. However, the cognitive mechanisms of the QE and, specifically, how the QED affects performance are not yet fully understood. We review research that has examined the functional mechanism underlying QE and discuss the neural networks that may be involved. We also highlight the limitations surrounding QE measurement and its definition and propose future research directions to address these shortcomings. Investigations into the behavioural and neural mechanisms of QE will aid the understanding of the perceptual and cognitive processes underlying expert performance and the factors that change as expertise develops
Rail Internet of Things: An Architectural Platform and Assured Requirements Model
Given the plethora of individual preferences and requirements of public transport passengers for travel, seating, catering, etc., it becomes very challenging to tailor generic services to individuals’ requirements using the existing service platforms. As tens of thousands of sensors have been already deployed along roadsides and rail tracks, and on buses and trains in many countries, it is expected that the introduction of IP networking will revolutionise the functionality of public transport in general and rail services in particular. In this paper, we propose a new communication paradigm to improve rail services and address the requirement of rail service users: the Rail Internet of Things (RIoT). To the best of our knowledge, it is the first work to define the RIoT and design an architectural platform that includes its components and the data communication channels. Moreover, we develop an assured requirements model using the situation calculus modelling to represent the fundamental requirements for adjustable, decentralised feedback control mechanisms necessary for the RIoT-ready software systems. The developed formal model is applied to demonstrate the design of passenger assistance software that interacts with the RIoT ecosystem and provides passengers with real-time information that is tailored to their requirements with runtime adaptability.
Keywords—Assistance; Assured model; Inclusive; IoT; Rail
Internet of Things (RIoT); Situation Calculu
An analysis of County Sports Partnerships in England: The fragility, challenges and complexity of partnership working in sports development
The management, use and reliance upon multi-agency partnerships in the field of public sector sports development became increasingly important following the election of the ‘New’ Labour government in 1997. In this study one example of a multi-agency partnership – County Sports Partnership (CSP) – will be examined through a case study analysis of four CSPs in the East Midlands region of England. A review of the theoretical and conceptual literature around partnership working will inform an appraisal of the impact of CSP arrangements in this region. The theoretical framework of partnership dynamics is utilized to explore the reality of partnership working in sports development in conjunction with the findings of four in-depth interviews that were conducted with Chief Executive Officers and senior managers in each of the CSP regions. In particular, consideration will be given to the potential implications and issues of ‘working in partnership’ for public sector sports development officers and managers who negotiate the complex and challenging policy environment surrounding multi-agency working in sport. The key findings of the research include the extent to which there appears to be a misunderstanding of the CSP role amongst some CSP partner agencies; the fragility of partnership working; the importance of relationship management; and the complex shifting politics of sports development policy
The use of craniofacial superimposition for disaster victim identification
Skull-to-face comparison is utilised for human identification where there is a suspected identity and the usual methods of identification, such as DNA or dental comparison, are not possible or practical. This research aimed to compare the reliability of manual and computerised craniofacial superimposition techniques and to establish the application of these techniques for disaster victim identification, where there may be a large database of passport-style images, such as the MPUB Interpol database. Twenty skulls (10 females; 10 males) were utilised from the William Bass Skeletal Collection at the University of Tennessee and compared to face pools of 20 face photographs of similar sex, age and ethnic group. A traditional manual photographic method and a new 3D computer-based method were used. The results suggested that profile and three-quarter views of the ante-mortem face were the most valuable for craniofacial superimposition. However, the poor identification rate achieved using images in frontal view suggests that the MPUB Interpol database would not be optimal for disaster victim identification, and passport-style images do not provide enough distinguishing facial detail. This suggests that multiple ante-mortem images with a variety of facial expression should be utilised for identification purposes. There was no significant difference in success between the manual and computer methods
Optimal Currency Composition for China’s Foreign Reserves: a Copula Approach
This paper investigates the optimal currency composition for a country's foreign reserves. In the context of China, we examine the asymmetric, fat-tail and complex dependence structure in distributions of currency returns. A skewed, fat-tailed and pair-copula construction is then built to capture features of higher moments. In a D-vine copula approach, we show that under the disappointment aversion effect, the central bank in our model can achieve sizeable gains in expected economic value from switching from the mean-variance to copula modelling. We find that this approach will lead to an optimal currency composition that allows China to have more space for international currency diversification while maintaining the leading position of the US dollar in the currency shares of China's reserves