Mean anisotropy of homogeneous Gaussian random fields and anisotropic norms of linear translation-invariant operators on multidimensional integer lattices

Sensitivity of output of a linear operator to its input can be quantified in various ways. In Control Theory, the input is usually interpreted as disturbance and the output is to be minimized in some sense. In stochastic worst-case design settings, the disturbance is considered random with imprecisely known probability distribution. The prior set of probability measures can be chosen so as to quantify how far the disturbance deviates from the white-noise hypothesis of Linear Quadratic Gaussian control. Such deviation can be measured by the minimal Kullback-Leibler informational divergence from the Gaussian distributions with zero mean and scalar covariance matrices. The resulting anisotropy functional is defined for finite power random vectors. Originally, anisotropy was introduced for directionally generic random vectors as the relative entropy of the normalized vector with respect to the uniform distribution on the unit sphere. The associated a-anisotropic norm of a matrix is then its maximum root mean square or average energy gain with respect to finite power or directionally generic inputs whose anisotropy is bounded above by a >= 0. We give a systematic comparison of the anisotropy functionals and the associated norms. These are considered for unboundedly growing fragments of homogeneous Gaussian random fields on multidimensional integer lattice to yield mean anisotropy. Correspondingly, the anisotropic norms of finite matrices are extended to bounded linear translation invariant operators over such fields

Simulating Autonomous Mobile Programs on Networks

Autonomous mobile programs (AMPs) have been proposed for load management in dynamic networks. An AMP is aware of its resource needs and periodically seeks a better location in the network to reduce execution time. AMPs have previously been measured using mobile Java Voyager on local area networks (LANs). We have constructed a simulation model of AMPs and reproduced 4 sets of experiments on homogeneous networks, i.e. networks where all locations have the same processor speed, and 2 sets of experiments on heterogeneous networks with collection of large and small AMPs. The results show that simulated collections of AMPs obtain similar balanced states to those reached in the real experiments, and have only minor differences from real experimental results. The simulation model gives an opportunity to explore the greedy effect that can be observed in the real experiments. This gives us confidence to apply the simulation model for further investigation of AMP behaviour, including behaviours on wide area networks

Sustainability transitions and the state

Sustainability transitions is an emerging field of research that has produced both conceptual understandings of the drivers of technological transitions, as well as more prescriptive and policy-engaged analyses of how shifts from unsustainable to sustainable forms of production and consumption can be achieved. Yet, attention towards the role of the state is underdeveloped in the field. The significance of this neglect has become more apparent in particular due to the heightened urgency around the need to tackle climate change and energy security, where there are increasing calls for an enhanced role for the state. This paper sets out to advance understandings of the multiple and conflicting roles that states play in transitions. It first addresses key weaknesses in the way the state has been examined thus far. Second, it highlights theoretical resources and conceptualisations of the state that can help scholars of transitions open up new and more productive avenues for understanding drivers and barriers to sustainable transitions drawing on examples from different sectors, regions and issue areas

Continuing Professional Development and Farm Business Performance

Economic and social pressures are transforming farm businesses and the structure of the agricultural industry, consequently it is presumed that farm management skills are under intense pressure. This creates a need for effective interaction between knowledge management and the actions taken by farm decision makers. However a definition of “successful farm business performance” is not easy to find and this, combined with literature that deals with managerial tasks in isolation, does not provide a clear picture for the farm manager pursuing self development. Farm businesses vary considerably in their attributes and resource base and the plethora of measurable factors mean that the manager needs to be able to identify what to measure and why on his own farm. In the UK it appears that most of the measures used in farming do not take into account the customer or human factors alluded to in other industries. Development of the skills and abilities of the decision makers to utilise techniques, interpret measures and relate them to their own business needs is increasingly important. The preliminary investigations described in this paper indicate that farmers and farm managers are aware of business management techniques but do not appear to integrate them fully into their own businesses.Farm Management, Teaching/Communication/Extension/Profession,

Reactions, Reflections and Responsibility: A \u27Responsive Evaluation\u27 of an Emerging Blended eLearning Subject

This paper discusses the findings of a qualitative investigation that sought to illuminate the perceived benefits of undertaking a blended learning subject at one tertiary institution. While there are several studies detailing the benefits of online learning, this study focussed on the student’s perceptions. What emerged from the analysis process were a series of themes related to the notion of authentic learning. Key processes of this perceived optimal learning site and space were the elements of group and individual reflection, and risk taking. Thus a heightened sense of ownership was developed. While the students believed that this form of tertiary learning had a ‘goodness of fit’ with how they used the Internet in their everyday lives, it would appear that they also required more explicit foci and instructions. Hence there is a need for further refinement and research in order to develop greater optimal learning spaces

Reactions, Reflections, and Responsibility: A Responsive Evaluation of an Emerging Blended E-learning Subject

In the decade since Schrum and Hong’s comment that “online learning has rapidly become a popular method of edu - cation for traditional and non-traditional students,” this approach to tertiary learning has morphed through several generational forms and platforms to the point where it has become firmly entrenched in the Australian tertiary landscape. As a broad generalization, e-learning, online, or flexible learning in many universities represents a spectrum of “information communications technology” (hereafter referred to as ICT) usage that ranges from little or no actual real-time interaction or “face-to-face” contact with associated viewing linkages such as YouTube through to teaching attempts at fully interactive programs. However, despite the numerous studies purporting the benefits of this form of study, a few voices have argued that this rapid shift has been “accepted uncritically.” Of late, there has also been a gathering chorus of research which suggests that the research base has been skewed, as it has not fully taken into account the understandings of the front-line users: the students themselves. This leads to the rationale of this article that what actually constitutes authentic “flexible learning,” its actual efficacy, and effects remain unclear. Emerging out of the context of standard online delivery is the notion of “blended learning” or “mixed mode learning.” In this learning mode, the ideal is that students retain some of the benefits of constant face-to-face interaction with peers and tutors, as well as the flexibility and less-restrictive nature of learning through technological access. However, blended learning in the Australian context has itself become situated across an ICT spectrum that ranges from the “provision of twoway communication so that the student may benefit from or even initiate dialogue” to the attempt at quasi-virtual situations of the “ClassSim” project

Development of probability of detection data for structural health monitoring damage detection techniques based on acoustic emission

Structural Health Monitoring (SHM) techniques have been developed as a cost effective alternative to currently adopted Non-Destructive Testing (NDT) methods which have well understood levels of performance. Quantitative performance assessment, as used in NDT, needs to be applied to SHM techniques to establish their performance levels as a basis for technique comparison and also as a requirement for practical aerospace application according to set regulations. One such measurand is Probability of Detection (POD). This paper reports experiments conducted to investigate the location accuracy of the Acoustic Emission (AE) system in monitoring events from HsuNielson and fatigue crack AE sources as a route to establish the POD of AE in SHM. It was found that fatigue crack tips could be located at 90% POD within 10 mm accuracy