952 resultados para Two Measures


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Pilot Youth Courts were introduced at Hamilton Sheriff Court in June 2003 and at Airdrie Sheriff Court in June 2004. Although introduced as one of a number of measures aimed at responding more effectively to youth crime (including young people dealt with through the Children’s Hearings System), the Youth Courts were intended for young people who would otherwise have been dealt with in the adult Sheriff Summary Court. The objectives of the pilot Youth Courts were to: • reduce the frequency and seriousness of re-offending by 16 and 17 year old offenders, particularly persistent offenders (and some 15 year olds who are referred to the court); • promote the social inclusion, citizenship and personal responsibility of these young offenders while maximising their potential; • establish fast track procedures for those young persons appearing before the Youth Court; • enhance community safety, by reducing the harm caused to individual victims of crime and providing respite to those communities which are experiencing high levels of crime; and • test the viability and usefulness of a Youth Court using existing legislation and to demonstrate whether legislative and practical improvements might be appropriate. Evaluation of the Hamilton and Airdrie Sheriff Youth Court pilots suggested that they had been successful in meeting the objectives set for them by the Youth Court Feasibility Group. Both were tightly run courts that dealt with a heavy volume of business. The particular strengths of the Youth Court model over previous arrangements included the fast-tracking of young people to and through the court, the reduction in trials, the availability of a wider range of resources and services for young people and ongoing judicial review. The successful operation of the pilot Youth Courts was dependent upon effective teamwork among the relevant agencies and professionals concerned. Good information sharing, liaison and communication appeared to exist across agencies and the procedures that were in place to facilitate the sharing of information seemed to be working well. This was also facilitated by the presence of dedicated staff within agencies, resulting in clear channels of communication, and in the opportunity provided by the multi-agency Implementation Groups to identify and address operational issues on an ongoing basis. However, whether Youth Courts are required in Scotland or whether procedural improvement were possible in the absence of dedicated resources and personnel was more difficult to assess. Two issues in particular required further attention. First, consideration needed to be given to whether the Youth Courts should be more explicitly youth focused and what this might entail. Second, greater clarity was required regarding for whom the Youth Courts were intended. This suggested the need for further discussion of Youth Court targeting and its potential consequences among the various agencies concerned.

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A range of varying chromophore nitroxide free radicals and their nonradical methoxyamine analogues were synthesized and their linear photophysical properties examined. The presence of the proximate free radical masks the chromophore’s usual fluorescence emission, and these species are described as profluorescent. Two nitroxides incorporating anthracene and fluorescein chromophores (compounds 7 and 19, respectively) exhibited two-photon absorption (2PA) cross sections of approximately 400 G.M. when excited at wavelengths greater than 800 nm. Both of these profluorescent nitroxides demonstrated low cytotoxicity toward Chinese hamster ovary (CHO) cells. Imaging colocalization experiments with the commercially available CellROX Deep Red oxidative stress monitor demonstrated good cellular uptake of the nitroxide probes. Sensitivity of the nitroxide probes to H2O2-induced damage was also demonstrated by both one- and two-photon fluorescence microscopy. These profluorescent nitroxide probes are potentially powerful tools for imaging oxidative stress in biological systems, and they essentially “light up” in the presence of certain species generated from oxidative stress. The high ratio of the fluorescence quantum yield between the profluorescent nitroxide species and their nonradical adducts provides the sensitivity required for measuring a range of cellular redox environments. Furthermore, their reasonable 2PA cross sections provide for the option of using two-photon fluorescence microscopy, which circumvents commonly encountered disadvantages associated with one-photon imaging such as photobleaching and poor tissue penetration.

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Contact lenses are a common method for the correction of refractive errors of the eye. While there have been significant advancements in contact lens designs and materials over the past few decades, the lenses still represent a foreign object in the ocular environment and may lead to physiological as well as mechanical effects on the eye. When contact lenses are placed in the eye, the ocular anatomical structures behind and in front of the lenses are directly affected. This thesis presents a series of experiments that investigate the mechanical and physiological effects of the short-term use of contact lenses on anterior and posterior corneal topography, corneal thickness, the eyelids, tarsal conjunctiva and tear film surface quality. The experimental paradigm used in these studies was a repeated measures, cross-over study design where subjects wore various types of contact lenses on different days and the lenses were varied in one or more key parameters (e.g. material or design). Both, old and newer lens materials were investigated, soft and rigid lenses were used, high and low oxygen permeability materials were tested, toric and spherical lens designs were examined, high and low powers and small and large diameter lenses were used in the studies. To establish the natural variability in the ocular measurements used in the studies, each experiment also contained at least one “baseline” day where an identical measurement protocol was followed, with no contact lenses worn. In this way, changes associated with contact lens wear were considered in relation to those changes that occurred naturally during the 8 hour period of the experiment. In the first study, the regional distribution and magnitude of change in corneal thickness and topography was investigated in the anterior and posterior cornea after short-term use of soft contact lenses in 12 young adults using the Pentacam. Four different types of contact lenses (Silicone hydrogel/ Spherical/–3D, Silicone Hydrogel/Spherical/–7D, Silicone Hydrogel/Toric/–3D and HEMA/Toric/–3D) of different materials, designs and powers were worn for 8 hours each, on 4 different days. The natural diurnal changes in corneal thickness and curvature were measured on two separate days before any contact lens wear. Significant diurnal changes in corneal thickness and curvature within the duration of the study were observed and these were taken into consideration for calculating the contact lens induced corneal changes. Corneal thickness changed significantly with lens wear and the greatest corneal swelling was seen with the hydrogel (HEMA) toric lens with a noticeable regional swelling of the cornea beneath the stabilization zones, the thickest regions of the lenses. The anterior corneal surface generally showed a slight flattening with lens wear. All contact lenses resulted in central posterior corneal steepening, which correlated with the relative degree of corneal swelling. The corneal swelling induced by the silicone hydrogel contact lenses was typically less than the natural diurnal thinning of the cornea over this same period (i.e. net thinning). This highlights why it is important to consider the natural diurnal variations in corneal thickness observed from morning to afternoon to accurately interpret contact lens induced corneal swelling. In the second experiment, the relative influence of lenses of different rigidity (polymethyl methacrylate – PMMA, rigid gas permeable – RGP and silicone hydrogel – SiHy) and diameters (9.5, 10.5 and 14.0) on corneal thickness, topography, refractive power and wavefront error were investigated. Four different types of contact lenses (PMMA/9.5, RGP/9.5, RGP/10.5, SiHy/14.0), were worn by 14 young healthy adults for a period of 8 hours on 4 different days. There was a clear association between fluorescein fitting pattern characteristics (i.e. regions of minimum clearance in the fluorescein pattern) and the resulting corneal shape changes. PMMA lenses resulted in significant corneal swelling (more in the centre than periphery) along with anterior corneal steepening and posterior flattening. RGP lenses, on the other hand, caused less corneal swelling (more in the periphery than centre) along with opposite effects on corneal curvature, anterior corneal flattening and posterior steepening. RGP lenses also resulted in a clinically and statistically significant decrease in corneal refractive power (ranging from 0.99 to 0.01 D), large enough to affect vision and require adjustment in the lens power. Wavefront analysis also showed a significant increase in higher order aberrations after PMMA lens wear, which may partly explain previous reports of "spectacle blur" following PMMA lens wear. We further explored corneal curvature, thickness and refractive changes with back surface toric and spherical RGP lenses in a group of 6 subjects with toric corneas. The lenses were worn for 8 hours and measurements were taken before and after lens wear, as in previous experiments. Both lens types caused anterior corneal flattening and a decrease in corneal refractive power but the changes were greater with the spherical lens. The spherical lens also caused a significant decrease in WTR astigmatism (WRT astigmatism defined as major axis within 30 degrees of horizontal). Both the lenses caused slight posterior corneal steepening and corneal swelling, with a greater effect in the periphery compared to the central cornea. Eyelid position, lid-wiper and tarsal conjunctival staining were also measured in Experiment 2 after short-term use of the rigid and SiHy contact lenses. Digital photos of the external eyes were captured for lid position analysis. The lid-wiper region of the marginal conjunctiva was stained using fluorescein and lissamine green dyes and digital photos were graded by an independent masked observer. A grading scale was developed in order to describe the tarsal conjunctival staining. A significant decrease in the palpebral aperture height (blepharoptosis) was found after wearing of PMMA/9.5 and RGP/10.5 lenses. All three rigid contact lenses caused a significant increase in lid-wiper and tarsal staining after 8 hours of lens wear. There was also a significant diurnal increase in tarsal staining, even without contact lens wear. These findings highlight the need for better contact lens edge design to minimise the interactions between the lid and contact lens edge during blinking and more lubricious contact lens surfaces to reduce ocular surface micro-trauma due to friction and for. Tear film surface quality (TFSQ) was measured using a high-speed videokeratoscopy technique in Experiment 2. TFSQ was worse with all the lenses compared to baseline (PMMA/9.5, RGP/9.5, RGP/10.5, and SiHy/14) in the afternoon (after 8 hours) during normal and suppressed blinking conditions. The reduction in TFSQ was similar with all the contact lenses used, irrespective of their material and diameter. An unusual pattern of change in TFSQ in suppressed blinking conditions was also found. The TFSQ with contact lens was found to decrease until a certain time after which it improved to a value even better than the bare eye. This is likely to be due to the tear film drying completely over the surface of the contact lenses. The findings of this study also show that there is still a scope for improvement in contact lens materials in terms of better wettability and hydrophilicity in order to improve TFSQ and patient comfort. These experiments showed that a variety of changes can occur in the anterior eye as a result of the short-term use of a range of commonly used contact lens types. The greatest corneal changes occurred with lenses manufactured from older HEMA and PMMA lens materials, whereas modern SiHy and rigid gas permeable materials caused more subtle changes in corneal shape and thickness. All lenses caused signs of micro-trauma to the eyelid wiper and palpebral conjunctiva, although rigid lenses appeared to cause more significant changes. Tear film surface quality was also significantly reduced with all types of contact lenses. These short-term changes in the anterior eye are potential markers for further long term changes and the relative differences between lens types that we have identified provide an indication of areas of contact lens design and manufacture that warrant further development.

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Existing secure software development principles tend to focus on coding vulnerabilities, such as buffer or integer overflows, that apply to individual program statements, or issues associated with the run-time environment, such as component isolation. Here we instead consider software security from the perspective of potential information flow through a program’s object-oriented module structure. In particular, we define a set of quantifiable "security metrics" which allow programmers to quickly and easily assess the overall security of a given source code program or object-oriented design. Although measuring quality attributes of object-oriented programs for properties such as maintainability and performance has been well-covered in the literature, metrics which measure the quality of information security have received little attention. Moreover, existing securityrelevant metrics assess a system either at a very high level, i.e., the whole system, or at a fine level of granularity, i.e., with respect to individual statements. These approaches make it hard and expensive to recognise a secure system from an early stage of development. Instead, our security metrics are based on well-established compositional properties of object-oriented programs (i.e., data encapsulation, cohesion, coupling, composition, extensibility, inheritance and design size), combined with data flow analysis principles that trace potential information flow between high- and low-security system variables. We first define a set of metrics to assess the security quality of a given object-oriented system based on its design artifacts, allowing defects to be detected at an early stage of development. We then extend these metrics to produce a second set applicable to object-oriented program source code. The resulting metrics make it easy to compare the relative security of functionallyequivalent system designs or source code programs so that, for instance, the security of two different revisions of the same system can be compared directly. This capability is further used to study the impact of specific refactoring rules on system security more generally, at both the design and code levels. By measuring the relative security of various programs refactored using different rules, we thus provide guidelines for the safe application of refactoring steps to security-critical programs. Finally, to make it easy and efficient to measure a system design or program’s security, we have also developed a stand-alone software tool which automatically analyses and measures the security of UML designs and Java program code. The tool’s capabilities are demonstrated by applying it to a number of security-critical system designs and Java programs. Notably, the validity of the metrics is demonstrated empirically through measurements that confirm our expectation that program security typically improves as bugs are fixed, but worsens as new functionality is added.

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Each financial year concessions, benefits and incentives are delivered to taxpayers via the tax system. These concessions, benefits and incentives, referred to as tax expenditure, differ from direct expenditure because of the recurring fiscal impact without regular scrutiny through the federal budget process. There are approximately 270 different tax expenditures existing within the current tax regime with total measured tax expenditures in the 2005-06 financial year estimated to be around $42.1 billion, increasing to $52.7 billion by 2009-10. Each year, new tax expenditures are introduced, while existing tax expenditures are modified and deleted. In recognition of some of the problems associated with tax expenditure, a Tax Expenditure Statement, as required by the Charter of Budget Honesty Act 1988, is produced annually by the Australian Federal Treasury. The Statement details the various expenditures and measures in the form of concessions, benefits and incentives provided to taxpayers by the Australian Government and calculates the tax expenditure in terms of revenue forgone. A similar approach to reporting tax expenditure, with such a report being a legal requirement, is followed by most OECD countries. The current Tax Expenditure Statement lists 270 tax expenditures and where it is able to, reports on the estimated pecuniary value of those expenditures. Apart from the annual Tax Expenditure Statement, there is very little other scrutiny of Australia’s Federal tax expenditure program. While there has been various academic analysis of tax expenditure in Australia, when compared to the North American literature, it is suggested that the Australian literature is still in its infancy. In fact, one academic author who has contributed to tax expenditure analysis recently noted that there is ‘remarkably little secondary literature which deals at any length with tax expenditures in the Australian context.’ Given this perceived gap in the secondary literature, this paper examines fundamental concept of tax expenditure and considers the role it plays in to the current tax regime as a whole, along with the effects of the introduction of new tax expenditures. In doing so, tax expenditure is contrasted with direct expenditure. An analysis of tax expenditure versus direct expenditure is already a sophisticated and comprehensive body of work stemming from the US over the last three decades. As such, the title of this paper is rather misleading. However, given the lack of analysis in Australia, it is appropriate that this paper undertakes a consideration of tax expenditure versus direct expenditure in an Australian context. Given this proposition, rather than purport to undertake a comprehensive analysis of tax expenditure which has already been done, this paper discusses the substantive considerations of any such analysis to enable further investigation into the tax expenditure regime both as a whole and into individual tax expenditure initiatives. While none of the propositions in this paper are new in a ‘tax expenditure analysis’ sense, this debate is a relatively new contribution to the Australian literature on the tax policy. Before the issues relating to tax expenditure can be determined, it is necessary to consider what is meant by ‘tax expenditure’. As such, part two if this paper defines ‘tax expenditure’. Part three determines the framework in which tax expenditure can be analysed. It is suggested that an analysis of tax expenditure must be evaluated within the framework of the design criteria of an income tax system with the key features of equity, efficiency, and simplicity. Tax expenditure analysis can then be applied to deviations from the ideal tax base. Once it is established what is meant by tax expenditure and the framework for evaluation is determined, it is possible to establish the substantive issues to be evaluated. This paper suggests that there are four broad areas worthy of investigation; economic efficiency, administrative efficiency, whether tax expenditure initiatives achieve their policy intent, and the impact on stakeholders. Given these areas of investigation, part four of this paper considers the issues relating to the economic efficiency of the tax expenditure regime, in particular, the effect on resource allocation, incentives for taxpayer behaviour and distortions created by tax expenditures. Part five examines the notion of administrative efficiency in light of the fact that most tax expenditures could simply be delivered as direct expenditures. Part six explores the notion of policy intent and considers the two questions that need to be asked; whether any tax expenditure initiative reaches its target group and whether the financial incentives are appropriate. Part seven examines the impact on stakeholders. Finally, part eight considers the future of tax expenditure analysis in Australia.

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Can art be simultaneously modern and traditional? This short piece examines the perplexities involved in seeking to address both cultural parameters at once in indigenous art of Australia.

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This study describes the treatment of obese individuals who rated high on emotional eating using four case studies that involved 22 sessions of either cognitive behavioral therapy (CBT) or dialectical behavioral therapy (DBT). Outcomes measures relating to weight, body mass index, emotional eating, depression, anxiety, and stress were all assessed with each participant prior to each baseline (three weekly sessions), during treatment and posttherapy. At the 8-week follow-up, the two cases that had received DBT had lost 10.1% and 7.6% of their initial body weight, whereas the two cases that had received CBT had lost 0.7% and 0.6% of their initial body weight. The two DBT cases also exhibited reductions in emotional distress, frequency of emotional eating or quantity of food eating in response to emotions, whereas the two CBT cases showed no overall reductions in these areas. Important processes from all four cases are described as are the implications to clinicians for developing more effective interventions for obese clients who engage in emotional eating.

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This article recognises the potential importance of Islamic finance products in Australia, along with the current regulatory impediments preventing Australia from becoming a leader in the Asia-Pacific Islamic finance market. Taking into account the potential importance of, and impediments to, Islamic finance, this article highlights, through the historical development and contemporary state of Islamic finance, its economic, social and political benefits to Australia. Once a case for embracing Islamic finance is made, the main current regulatory impediments to Australia becoming a key player in the Islamic finance market within the Asia-Pacific region are highlighted. This article then argues that, rather than requiring any separate regulatory regime, the current regulatory impediments may be overcome through amendments to existing laws to ensure parity of treatment in Australia between the Islamic finance market and the conventional finance market. The Australian income tax regime is utilised as a case study demonstrate how parity of treatment could be achieved via amendment by taking two frequent and separate Islamic finance transactions. This article concludes that the economic, social and political benefits potentially warrant Australia embracing Islamic finance and that, with the right regulatory measures, Australia could lay the foundation to become a leader in the Asia-Pacific Islamic finance market.

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Prevention and safety promotion programmes. Traditionally, in-depth investigations of crash risks are conducted using exposure controlled study or case-control methodology. However, these studies need either observational data for control cases or exogenous exposure data like vehicle-kilometres travel, entry flow or product of conflicting flow for a particular traffic location, or a traffic site. These data are not readily available and often require extensive data collection effort on a system-wide basis. Aim: The objective of this research is to propose an alternative methodology to investigate crash risks of a road user group in different circumstances using readily available traffic police crash data. Methods: This study employs a combination of a log-linear model and the quasi-induced exposure technique to estimate crash risks of a road user group. While the log-linear model reveals the significant interactions and thus the prevalence of crashes of a road user group under various sets of traffic, environmental and roadway factors, the quasi-induced exposure technique estimates relative exposure of that road user in the same set of explanatory variables. Therefore, the combination of these two techniques provides relative measures of crash risks under various influences of roadway, environmental and traffic conditions. The proposed methodology has been illustrated using Brisbane motorcycle crash data of five years. Results: Interpretations of results on different combination of interactive factors show that the poor conspicuity of motorcycles is a predominant cause of motorcycle crashes. Inability of other drivers to correctly judge the speed and distance of an oncoming motorcyclist is also evident in right-of-way violation motorcycle crashes at intersections. Discussion and Conclusions: The combination of a log-linear model and the induced exposure technique is a promising methodology and can be applied to better estimate crash risks of other road users. This study also highlights the importance of considering interaction effects to better understand hazardous situations. A further study on the comparison between the proposed methodology and case-control method would be useful.

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Background Pakistan has the highest population rate of road fatalities in South Asia (25.3 fatalities per 100,000 people: Global Status Report on Road Safety, WHO 2009). Along with road environment and vehicle factors, human factors make a substantial contribution to traffic safety in Pakistan. Beliefs about road crash causation and prevention have been demonstrated to contribute to risky road use behaviour and resistance to preventive measures in a handful of other developing countries, but has not been explored in Pakistan. In particular, fatalism (whether based on religion, other cultural beliefs or experience) has been highlighted as a barrier to achieving changes in attitudes and behaviour. Aims The research reported here aimed (i) to explore perceptions of road crash causation among policy makers, police officers, professional drivers and car drivers in Pakistan; (ii) to identify how cultural and religious beliefs influence road use behaviour in Pakistan; and (iii) to understand how fatalistic beliefs may work as obstacles to road safety interventions. Methods In-depth interviews were conducted by the primary author (mostly in Urdu) in Lahore, Rawalpindi and Islamabad with 12 professional drivers (taxi, bus and truck), 4 car drivers, 6 police officers, 4 policy makers and 2 religious orators. All but two were Muslim, two were female, and they were drawn from a wide range of ages (24 to 60) and educational backgrounds. The interviews were taped and transcribed, then translated into English and analysed for themes related to the aims. Results Fatalism emerged as a pervasive belief utilised to justify risky road use behaviour and to resist messages about preventive measures. There was a strong religious underpinning to the statement of fatalistic beliefs (this reflects popular conceptions of Islam rather than scholarly interpretations), but also an overlap with superstitious beliefs which have longer-standing roots in Pakistani culture. These beliefs were not limited to people of poor educational background or position. A particular issue which was explored in more detail was the way in which these beliefs and their interpretation within Pakistani society contributed to poor police reporting of crashes. Discussion and conclusions The pervasive nature of fatalistic beliefs in Pakistan affects road user behaviour by supporting continued risk taking behaviour on the road, and by interfering with public health messages about behaviours which would reduce the risk of traffic crashes. The widespread influence of these beliefs on the ways that people respond to traffic crashes and the death of family members contribute to low crash reporting rates and to a system which is difficult to change. The promotion of an evidence-based approach to road user behaviour is recommended, along with improved professional education for police and policy makers.

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Injury is the leading cause of death among young people, and involvement in health risk behaviors, such as alcohol use and transport-related risks, is related to increased risk for injury. Effective health promotion programs for adolescents focus on multiple levels, including relationships with peers and parents, student knowledge, behavior and attitudes, and school-level factors such as school connectedness. This study describes the pilot evaluation of a comprehensive, multi-level injury prevention program for 13-14 year old adolescents, targeting change in injury associated with transport and alcohol risks. The program, called Skills for Preventing Injury in Youth (SPIY), incorporates two primary elements: an 8-week, teacher delivered attitude and behavior change curriculum with peer protection and first aid messages; and professional development for program teachers focusing on strategies to increase students’ connectedness to school. Five Australian high schools were recruited for the pilot evaluation research, with three being assigned to receive intervention components and two assigned as curriculum-as-usual controls. In the intervention schools, 118 Year 8 students participated in surveys at baseline, with 105 completing surveys at follow up, six months following the intervention. In the control schools, 196 Year 8 students completed surveys at baseline and 207 at follow up. Survey measures included self-reported injury, risk taking behavior and school connectedness. Results showed that students in the control schools were significantly more likely to report riding bikes without helmets, riding with dangerous drivers, having driven cars on the road, and using alcohol six months after the program, while the intervention group showed no such increase in these behaviors. Additionally, students in the control schools were significantly more likely to report having had pedestrian-related injuries at follow up than they were at the baseline measurement, while intervention school students showed no change. There was also a trend observed in terms of a decrease in bicycle related injuries among intervention school students, compared with a slight increasing trend in bicycle injuries among control students. Overall, scores on the school connectedness scale decreased significantly from baseline to follow up for both intervention and control students, however measurement limitations may have impacted on results relating to students’ connectedness. Overall, the SPIY program has shown promising results in regards to prevention of students’ health risk behavior and injuries. Evidence suggests that the curriculum component was important; however there was limited evidence to suggest that teacher training in school connectedness strategies contributed to these promising results. While school connectedness may be an important factor to target in risk and injury prevention programs, programs may need to incorporate whole-of-school strategies or target a broader range of teachers than were selected for the current research.

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A standard method for the numerical solution of partial differential equations (PDEs) is the method of lines. In this approach the PDE is discretised in space using �finite di�fferences or similar techniques, and the resulting semidiscrete problem in time is integrated using an initial value problem solver. A significant challenge when applying the method of lines to fractional PDEs is that the non-local nature of the fractional derivatives results in a discretised system where each equation involves contributions from many (possibly every) spatial node(s). This has important consequences for the effi�ciency of the numerical solver. First, since the cost of evaluating the discrete equations is high, it is essential to minimise the number of evaluations required to advance the solution in time. Second, since the Jacobian matrix of the system is dense (partially or fully), methods that avoid the need to form and factorise this matrix are preferred. In this paper, we consider a nonlinear two-sided space-fractional di�ffusion equation in one spatial dimension. A key contribution of this paper is to demonstrate how an eff�ective preconditioner is crucial for improving the effi�ciency of the method of lines for solving this equation. In particular, we show how to construct suitable banded approximations to the system Jacobian for preconditioning purposes that permit high orders and large stepsizes to be used in the temporal integration, without requiring dense matrices to be formed. The results of numerical experiments are presented that demonstrate the effectiveness of this approach.

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The incidence of sleep-related crashes has been estimated to account for approximately 20% of all fatal and severe crashes. The use of sleepiness countermeasures by drivers is an important component to reduce the incidence rates of sleep-related crashes. Taking a brief nap and stopping for a rest break are two highly publicised countermeasures for driver sleepiness and are also believed by drivers to be the most effective countermeasures. Despite this belief, there is scarce evidence to support the utility of these countermeasures for reducing driver sleepiness levels. Therefore, determining the effectiveness of these countermeasures is an important road safety concern. The current study utilised a young adult sample (N = 20) to investigate the effectiveness of a nap and an active rest break. The countermeasures effects were evaluated by physiological, behavioural (hazard perception skill), and subjective measures previously found sensitive to sleepiness. Participants initially completed two hours of a simulated driving task followed by a 15 minute nap opportunity or a 15 minute active rest break that included 10 minutes of brisk walking. After the break, participants completed one final hour of the simulated driving task. A within-subjects design was used so that each participant completed both the nap and the active rest break conditions on separate occasions. The analyses revealed that only the nap break provided any meaningful reduction in physiological sleepiness, reduced subjective sleepiness levels, and maintained hazard perception performance. In contrast, the active rest break had no effect for reducing physiological sleepiness and resulted in a decrement in hazard perception performance (i.e., an increase of reaction time latencies), with a transient reduction in subjective sleepiness levels. A number of theoretical, empirical and practical issues were identified by the current study.

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This work presents two UAS See and Avoid approaches using Fuzzy Control. We compare the performance of each controller when a Cross-Entropy method is applied to optimase the parameters for one of the controllers. Each controller receive information from an image processing front-end that detect and track targets in the environment. Visual information is then used under a visual servoing approach to perform autonomous avoidance. Experimental flight trials using a small quadrotor were performed to validate and compare the behaviour of both controllers