A practical condition for migration dynamic recrystallization

A readily evaluated condition for migration dynamic recrystallization is developed. It is based on the postulate that “the distance traversed by the boundary of a hypothetical growing grain in the time taken for the attainment of a recovery steady state must exceed the size of a critical nucleus”. A method for estimating the boundary mobility based on the kinetics of static recrystallization is also developed to facilitate evaluation of the condition. The derivation focuses first on developing an upper limit for the dynamically recrystallized grain size. This upper limit is only slightly higher than experimental values. The critical condition also agrees well with a limited set of experimental data. These data include the occurrence (and, in two cases, suppression) of dynamic recrystallization in Cu, Ni, Mg, α-Fe, γ-Fe and Al.

The role of dualities in arbitrating continuity and change in forms of organizing

A substantial body of literature on new forms of organizing has forecast the end of bureaucracy. More recent empirical studies, however, indicate that high-performing organizations are adopting dual forms of organizing in which the controllability advantages associated with traditional forms work to complement and support the responsiveness attributes of new forms of organizing. The paradox is that, if organizations discard the key planning, co-ordinating and direction-setting mechanisms of traditional forms of organizing, they also remove the stabilizing dimensions of organizational form that are essential in periods of uncertainty and change. The challenge for organizations lies in learning how to manage the tensions or dualities between traditional and new forms of organizing, a process demanding the arbitration of continuity and change. This paper explores the concept of dualities and its salience in the management of organizing forms. First, the nature of dualities is explained; secondly, a set of characteristics is developed to describe the behaviour of dualities; and thirdly, suggestions are presented for arbitrating the tensions that exist in organizing form dualities. These three contributions are relevant because they signal the route to the effective creation and management of organizing form dualities, the benefit of which is the constructive combination of dynamic capabilities (underpinning innovation and responsiveness, the hallmarks of new forms of organizing) and operational capabilities (underpinning stability and efficiency, the hallmarks of traditional forms of organizing).

Towards a digital representation of physical phenomena to assess comfort in future environments

This paper presents the concept and a test implementation of a digital representation of the physical world designed to assess comfort quality in
future environments. An integrated set of physical phenomena is modeled three-dimensionally to investigate the dynamic behavior of design objects
holistically.

The formulation supports the integration of computational simulation in the performance-based design process. It employs the principles of
geometrical and physical selfcontainedness to avoid that complex geometrical and physical circumstances have to be specified at design time. The concepts of congeneric cells and congeneric conjunctions are
introduced to simulate various physical phenomena simultaneously with a uniformly structured set of equations.

The concept, the prototype implementation and selected test cases are presented. Although it was not possible to implement all features and model parts completely, the research and the discussion of its achievements make valuable contributions towards more effective integration of computational simulation in the performance-based design process.

The application of rough set and Kohonen network to feature selection for object extraction

Selecting a set of features which is optimal for a given task is a problem which plays an important role in a wide variety of contexts including pattern recognition, images understanding and machine learning. The paper describes an application of rough sets method to feature selection and reduction in texture images recognition. The proposed methods include continuous data discretization based on Kohonen neural network and maximum covariance, and rough set algorithms for feature selection and reduction. The experiments on trees extraction from aerial images show that the methods presented in this paper are practical and effective.

Global branding and strategic CSR : an overview of three types of complexity

Purpose – There is general agreement that global brands should ensure that they incorporate social responsibility. To do this properly, organisations must understand what it means to be socially responsible and how they can leverage their actions. The paper proposes consideration of three distinct areas: the range of social responsibility issues, what the organisations actually do and how to leverage those corporate social responsibility (CSR) actions. This paper seeks to conceptually develop these three areas of complexity – Issue, Organisational and Communication – as it is only after organisations understand these three areas that they can effectively leverage socially responsible activities in their brands.

Design/methodology/approach – This research undertakes a review and synthesis of the academic, practitioner and industry literature examining CSR and the brand, addressing the three areas of complexity – issue, organisational and communication.

Findings – The research finds that within these three areas of complexity there are a number of sub-issues that must be addressed if CSR is to be strategically integrated into a global brand. This includes sub-issues associated with social issue complexity (identification, heterogeneity, measurement, and interpretation); organizational complexity (overall corporate brand, multiple products and brands, functional activities, and supply chain); and communication complexity (intensity of action/positioning, communicating action, types of programs utilised, and integration issues.) It thus provides an agenda for future research.

Research limitations/implications – There is limited academic literature examining how global organisations incorporate CSR activities into their brand and the research proposes the issues that need to be considered when integrating CSR into branding strategy. Future research needs to be undertaken to explore the internal processes that global firms use to develop their CSR positioning strategies and some research propositions for future research are proposed. Additionally further exploration of each of the issues (and sub-issues) identified in this paper is warranted, and some suggestions are made for this.

Practical implications – The results of this study show that developing a CSR leveraged brand in a consistent way that is salient to all stakeholders is no simple task for global organisations. By considering the three areas of complexity developed here organisations will be able to better understand and align their activities in line with CSR related issues. Being global means that organisations will likely need to ensure they address the highest set of global expectations, as any lower level may be criticised as being less than appropriate.

Originality/value – The paper develops the sub-issues of issue, organisational and communication complexity associated with global brands' CSR activities. This strategic perspective goes beyond focusing on the tactical activities undertaken or the philosophical issue of whether CSR should be undertaken. The work therefore allows global organisations to look at CSR more strategically as a branding issue.

Sydney principles for reducing the commercial promotion of foods and beverages to children

A set of seven principles (the ‘Sydney Principles’) was developed by an International Obesity Taskforce (IOTF) Working Group to guide action on changing food and beverage marketing practices that target children. The aim of the present communication is to present the Sydney Principles and report on feedback received from a global consultation (November 2006 to April 2007) on the Principles.

The Principles state that actions to reduce marketing to children should: (i) support the rights of children; (ii) afford substantial protection to children; (iii) be statutory in nature; (iv) take a wide definition of commercial promotions; (v) guarantee commercial-free childhood settings; (vi) include cross-border media; and (vii) be evaluated, monitored and enforced.

The draft principles were widely disseminated and 220 responses were received from professional and scientific associations, consumer bodies, industry bodies, health professionals and others. There was virtually universal agreement on the need to have a set of principles to guide action in this contentious area of marketing to children. Apart from industry opposition to the third principle calling for a statutory approach and several comments about the implementation challenges, there was strong support for each of the Sydney Principles. Feedback on two specific issues of contention related to the age range to which restrictions should apply (most nominating age 16 or 18 years) and the types of products to be included (31 % nominating all products, 24 % all food and beverages, and 45 % energy-dense, nutrient-poor foods and beverages).

The Sydney Principles, which took a children’s rights-based approach, should be used to benchmark action to reduce marketing to children. The age definition for a child and the types of products which should have marketing restrictions may better suit a risk-based approach at this stage. The Sydney Principles should guide the formation of an International Code on Food and Beverage Marketing to Children.

The mother-daughter guilt dynamic : effects of type 1 diabetes during life transitions

Aim. The aim of the study was to explore and describe the strategies young women with type 1 diabetes used to manage life transitions. The paper describes one aspect of how guilt dynamic often operates between mothers and daughters and how the women managed the guilt dynamic to create stability in their lives.
Background. When a child is diagnosed with diabetes, major transitional changes occur in the relationships between the mother and her child. The changes affect the psychological and social aspects of their lives and have a major impact on how young women manage their diabetes. A guilt dynamic between mothers and young women with diabetes emerged as a major theme in a larger study that investigated how young women with diabetes managed life transitions. Although the literature indicates that mothers of chronically ill children experience guilt feelings towards their children, little research was identified that addressed the emotional dynamics between mothers and daughters with diabetes.
Design. Using grounded theory method, interviews were conducted with 20 women with type 1 diabetes and five mothers during 2002 and 2003. Constant comparative analysis was used to analyse the data and develop an in-depth understanding of the experience of living with diabetes during life transitions.
Findings. The findings revealed that guilt feelings created a two-way dependency between mothers and their daughters with diabetes. The two-way dependency involved feelings of being a burden to each other, difficulty balancing responsibilities for diabetes management, difficulty relinquishing emotional and social dependency especially during life transitions. In addition, these issues were rarely discussed openly with each other or with health professionals. The findings provide additional information about the human experience of the mother–daughter relationship and the effect on coping with diabetes in the context of life transitions.
Conclusions. Understanding the impact diabetes has on the emotional and social well being of both women with type 1 diabetes and their mothers is critical in planning appropriate support for both groups. Most importantly, it is critical to understand the guilt dynamic that operates during young women with diabetes' life transitions when the daughters' dependency on their mother's control and responsibility for diabetes management undergo changes resulting in emotional responses, especially guilt feelings.
Relevance to clinical practice. Health professionals need to understand the emotional and social impact of the guilt dynamics between young women with type 1 diabetes and their mothers. Adequate and appropriate support can minimize the guilt feelings and enhance stability and quality of life for both mothers and their daughters, especially during major life transitions, such as motherhood.

Influence of an adventure learning program, using group adventure initiative tasks, on participant self-esteem

The purpose of this study was to assess the influence of an adventure learning program, based on participation in group adventure initiative tasks (GAITs), on participant self-esteem and, further, to examine any associated gender differences in the dependent variable. The study took place within the framework of the 'Group Dynamics in Action' unit offered at the University of South Australia, Underdale Campus, in semester 2, 1994. The course included participation in group adventure initiative tasks, the identification and examination of group dynamic processes, the investigation of individual roles within the small group and the review of these processes in the group setting. The program also included an experience on a high ropes course. Both quantitative and qualitative data was gathered to gain insight into gender differences and their relationship to the dependent variable and also to provide insight into any discrepancy in outcomes between males and females with regard to participation in group adventure initiative tasks. The sample set of participants was drawn from undergraduate students studying at the University of South Australia in the Bachelor of Teaching (Primary), Bachelor of Education (Secondary Physical Education Teaching) and Bachelor of Applied Science (Exercise and Sport Science) courses. Subjects were assigned to either experimental or control conditions and the experimental group were then randomly assigned to one of three treatment groups. Sixty one (N = 61) male and female subjects were tested pre and post-treatment period. Psychological tests included the Coopersmith Self Esteem Inventory (Coopersmith 1981) and an adaptation of Coopersmith's Behaviour Rating Form (Coopersmith 1967). Qualitative data was gathered using Kuhn's Twenty Statements Test (Kuhn and McPartland 1954), a self-esteem questionnaire, observations made by the researcher and other staff about subjects interactions and from weekly journals kept by subjects throughout the treatment. The duration of the treatment period was 14 weeks consisting of 14, 2 hour seminars.

Ideal golf swing : an evaluation of its characteristics and the assumptions underlying its acquisition during coaching

The game of golf requires hitting a ball from a range of lies over a range of distances in environments that include many obstacles to be avoided. Each of these different golf shots arc designed to move the ball from the tee to the hole in the least number of strokes. However, the fundamental assumption that seems to underlie the coaching of golf, particularly to novice players, is that acquisition of an ideal basic golf swing is the most important outcome of coaching. Implicit in this view are three further assumptions. The first is that once this ideal basic golf swing is acquired by players, they are able to complete a game of golf in a competent manner even though this requires a range of different shots. The second is that there is a close correspondence between the quality of execution of any golf swing as judged in terms of this ideal swing, and the quality of outcome of the golf shot of which the swing is a part, as judged by where the ball comes to rest. The third assumption is that visual inspection of the golf swing by a coach can reveal inadequacies which can be remedied leading lo improved performance in the game of golf. The research reported in this thesis is an investigation of these assumptions. The rationale underlying coaching of golf was examined by reviewing the golf coaching literature (Chapter 1) and conducting a survey of professional golf coaches (Chapter 2). Results of the literature review and the survey indicated that the major emphasis of golf coaching of novices was on their acquiring what might be described as an ideal basic golf swing. This typically involved identifying components in sequence. Little emphasis was placed during this stage of coaching on what might be described as the complete action of a golf shot which involves hitting a ball to some target location. To examine the assumption that there was a close correspondence between the quality of execution of the golf swing and the quality of the outcome of a golf shot, two studies were conducted. In Chapter 3 the development of a 70-item checklist to be used to evaluate the quality of execution of a golf swing is reported. This checklist was based on a detailed behavioural analysis of the golf swing involving collaboration with relevant experts (i.e., golf coaches, biomechanist, kinesiologist), and information derived from a review of golf coaching materials. Development of the checklist was an iterative process in which earlier versions were used to evaluate sample golf swings, and problems identified during this lest process were used to improve the checklist. The final 70-item checklist comprised of a static component with three parts (left-hand grip; right-hand grip; stance) and a dynamic component with six parts (half backswing; full backswing; half downswing; ball contact; half followthrough; finish position). This version of the checklist was used in a study (reported in Chapter 4) of the relationship between the judged quality of execution of a golf swing and the outcome accuracy of a golf shot. Three groups of golfers with varying ability and experience were required to hit 50 balls with a 9-iron club to a target. Outcome accuracy for each shot was assessed in terms of the distance between the target and the resting location of the ball. Edited videotapes (showing only execution of the golf swing) of the five most, and five least accurate shots produced a sub-sample of these golfers (four professional players; four novice players) were subsequently viewed by three expert coaches. They independently rated using the checklist, the quality of execution of the 80 golf swings in random order without having information about the accuracy of any shot. As expected, the professional golfers completed more accurate golf shots than did the novices, and the golf swings completed by the professionals were rated more highly than those completed by the novices. However, for both groups of golfers the results indicated that there was no clear relationship between the rated quality of execution of golf swings and the outcome accuracy of the shots of which the swing were the initial part. Chapter 5 provides a summary and overview of the research reported in Chapter 1 to 4. It is argued that this research suggests a need for a change of emphasis in golf coaching away from consideration of the golf swing in isolation to consideration of the golf swing as part of a complete action. That is, the quality of execution of a golf swing should not be judged simply in relation to some ideal set of golf-swing components, but rather in relation to how well the completed swing (i.e., the golf shot) achieves the desired aim of propelling the ball from its present location to the target location.

Management of SPMD based parallel processing on clusters of workstations

Current attempts to manage parallel applications on Clusters of Workstations (COWs) have either generally followed the parallel execution environment approach or been extensions to existing network operating systems, both of which do not provide complete or satisfactory solutions. The efficient and transparent management of parallelism within the COW environment requires enhanced methods of process instantiation, mapping of parallel process to workstations, maintenance of process relationships, process communication facilities, and process coordination mechanisms. The aim of this research is to synthesise, design, develop and experimentally study a system capable of efficiently and transparently managing SPMD parallelism on a COW. This system should both improve the performance of SPMD based parallel programs and relieve the programmer from the involvement into parallelism management in order to allow them to concentrate on application programming. It is also the aim of this research to show that such a system, to achieve these objectives, is best achieved by adding new special services and exploiting the existing services of a client/server and microkernel based distributed operating system. To achieve these goals the research methods of the experimental computer science should be employed. In order to specify the scope of this project, this work investigated the issues related to parallel processing on COWs and surveyed a number of relevant systems including PVM, NOW and MOSIX. It was shown that although the MOSIX system provide a number of good services related to parallelism management, none of the system forms a complete solution. The problems identified with these systems include: instantiation services that are not suited to parallel processing; duplication of services between the parallelism management environment and the operating system; and poor levels of transparency. A high performance and transparent system capable of managing the execution of SPMD parallel applications was synthesised and the specific services of process instantiation, process mapping and process interaction detailed. The process instantiation service designed here provides the capability to instantiate parallel processes using either creation or duplication methods and also supports multiple and group based instantiation which is specifically design for SPMD parallel processing. The process mapping service provides the combination of process allocation and dynamic load balancing to ensure the load of a COW remains balanced not only at the time a parallel program is initialised but also during the execution of the program. The process interaction service guarantees to maintain transparently process relationships, communications and coordination services between parallel processes regardless of their location within the COW. The combination of these services provides an original architecture and organisation of a system that is capable of fully managing the execution of SPMD parallel applications on a COW. A logical design of a parallelism management system was developed derived from the synthesised system and was shown that it should ideally be based on a distributed operating system employing the client server model. The client/server based distributed operating system provides the level of transparency, modularity and flexibility necessary for a complete parallelism management system. The services identified in the synthesised system have been mapped to a set of server processes including: Process Instantiation Server providing advanced multiple and group based process creation and duplication; Process Mapping Server combining load collection, process allocation and dynamic load balancing services; and Process Interaction Server providing transparent interprocess communication and coordination. A Process Migration Server was also identified as vital to support both the instantiation and mapping servers. The RHODOS client/server and microkernel based distributed operating system was selected to carry out research into the detailed design and to be used for the implementation this parallelism management system. RHODOS was enhanced to provide the required servers and resulted in the development of the REX Manager, Global Scheduler and Process Migration Manager to provide the services of process instantiation, mapping and migration, respectively. The process interaction services were already provided within RHODOS and only required some extensions to the existing Process Manager and IPC Managers. Through a variety of experiments it was shown that when this system was used to support the execution of SPMD parallel applications the overall execution times were improved, especially when multiple and group based instantiation services are employed. The RHODOS PMS was also shown to greatly reduce the programming burden experienced by users when writing SPMD parallel applications by providing a small set of powerful primitives specially designed to support parallel processing. The system was also shown to be applicable and has been used in a variety of other research areas such as Distributed Shared Memory, Parallelising Compilers and assisting the port of PVM to the RHODOS system. The RHODOS Parallelism Management System (PMS) provides a unique and creative solution to the problem of transparently and efficiently controlling the execution of SPMD parallel applications on COWs. Combining advanced services such as multiple and group based process creation and duplication; combined process allocation and dynamic load balancing; and complete COW wide transparency produces a totally new system that addresses many of the problems not addressed in other systems.

Codes of ethics in large private sector Australian businesses

This thesis deals with codes of ethics in the top 500 companies operating in the private sector in Australia. We seek to answer two questions. First, can businesses adopt codes of ethics in a meaningful way, or are business ethics a contradiction in terms for profit seeking organisations in competitive markets? Second, to what extent do Australia’s top 500 private sector firms show commitment to codes of ethics? A number of ancillary questions are explored to form a picture of the current Australian situation and to compare it to the rest of the world, especially the US and Canada. Chapter 1 discusses these questions and the origins of the author’s interest in business ethics. This chapter develops a focus upon codes of ethics and their role in assisting to establish and maintain an ethical culture. The chapter looks at previous research on codes of ethics and demonstrates a lack of understanding in Australia on the subject and the need for research into it. Also included in Chapter 1 is the plan for the thesis. Chapters 2 to 4 review the literature upon which the thesis is based. In Chapter 2, the meaning of the terms ethics and business ethics are considered. Deontological and teleological approaches are distinguished and a (largely) teleological model of business ethics is developed. This chapter also asks whether business ethics are possible. The contention that ethics may be good for a business’s profit is explored in-depth and the conclusion is reached that ethics should be pursued for its inherent worth regardless of the economic benefit that can be attributed to it. A number of models of ethical decision making are discussed in Chapter 3 starting with Kohlberg and Kramer (1969). This discussion leads to the conclusion that organisations must create an ethical culture for staff if they require them to embrace ethical practices. If this is a correct conclusion, then the role of senior managers becomes critical in the process. Chapter 4 looks further at the role of senior managers, organisational culture and ethical/unethical behaviour in organisations. The conclusion is that senior managers do play an integral part in shaping the culture of an organisation. Their actions, either overtly or covertly, impact upon their staff and highlight behaviour that the organisation is or is not willing to tolerate. Sims (1991) proposed ten ways to foster an ethical culture and these ideas are set out and further explored through the work of other writers on management ethics. Finally, the link between ethics and strategic planning is examined. In Chapter 5 the methods used for empirical data gathering are described and justified. A number of factors that can lead us to consider a company’s ‘commitment’ to ethics are outlined. A survey of Australian companies was the primary means of data collection. Each question in the survey instrument is listed and explained. Also the survey response rate is reported, as are major demographic characteristics of respondents. Chapter 6 provides the research findings from the survey of the top 500 companies operating in the private sector in Australia. The research examines: i) the current Australian usage and implementation of codes of ethics; ii) the measures put in place in organisations in order to support a code; From this analysis conclusions are drawn about the ‘commitment’ of companies operating in Australia to codes of ethics. Australian companies are becoming aware of the potential of code usage. Companies operating in Australia that have codes appear to be good at implementing codes and examining staff performance in relation to codes. However, they lack the procedures that incorporate education and training and the implementation of the support mechanisms necessary to enhance employee understanding of the code. In Chapter 7, Australian codes are compared to American and Canadian codes for similarity and disparity. The assessment found that in all three countries codes are primarily concerned with company continuance. Australian codes do tend to be more socially oriented than in the other two countries and also less legalistic. Chapter 8 looks at 4 companies from the first survey that were asked for more in-depth information in a quest to determine current best practice in Australia. These organisations were chosen because they appeared, from the first survey instrument, to have put in place mechanisms to assist employees to better understand the code. The implication is that companies must make a conscious, positive effort to ensure that employees are considered in the process of ethical development. They should have input into the process, rather than just being directed to follow another management initiative. The final chapter summarises the research findings and looks at answers to the two major questions and the seven subordinate empirical questions posed at the start of the thesis. The conclusion reached is that companies operating in Australia appear to be moving towards establishing codes of ethics. Those who already have codes display a real commitment to them. The movement appears to be gathering momentum as more organisations see the value of incorporating ethical business practices into the every day workings of their individual companies. Generally, most Australian companies lag behind the rest of the world, but the pace-setting companies are defining their own best practice and achieving positive outcomes for themselves, their employees and other stakeholders.

Doing justice' : stories of everyday life in disadvantaged schools and neighbourhoods

I worked as a school administrator in 'disadvantaged schools' for many years. In this study I asked colleagues from sixteen schools in the northern and western suburbs of Adelaide to co - theorise about changes in their neighbourhood, school populations and programs, now that their schools are no longer recognised by policy as 'disadvantaged1. I explore the use of narrative method and arts based approaches by constructing a 'literary' research text that uses conventional sociological forms together with images, poetry and personal stories. I use anthropological and geographical theoretical constructs to look at the changing material, economic, cultural and social landscapes and the mosaic of inequalities in the city of Adelaide. I suggest that this is not a simple binary polarisation, although large numbers of people are similarly positioned by de-industrialisation and the diminishing social wage. After examining the literature on poverty in Australia, I am eventually prepared to call this space class, understanding that this is a sociological metaphor. Through a theorisation of each school as a 'place' within a specific neighbourhood, I look at the similarities and differences across sites. I suggest that 'disadvantaged schools' are similarly positioned as sites for the mediation of social inequalities, and that this can be readily seen in the time consuming 'housework' of discipline and welfare. I indicate how each school is differently able to 'do more with less', because of their unique neighbourhood and its narratives, knowledges, histories, teleologies and people. I show that the common coercive regimes of market devolution, new public management and the 'distributive curriculum' frame the work of teachers, students and administrators in ways that are not conducive to 'doing justice', despite the policy rhetoric of equity and community. I provide evidence that the neoliberal imaginary of context free schooling enshrined in effective schools literatures is Utopian and irrational. I argue that the capacity of the school to 'generate context' is always paradoxically dependent on 'context derived'. I discuss the notion of 'doing justice' and the benefits of 'disadvantaged schools' having a local set of principles that guide their decisions and actions and provide evidence that the school administrator's understandings of 'doing justice' are important. I also suggest that, despite being increasingly isolated and hindered by policy directions, the majority of the sixteen schools continue to work for and with principles of justice and equity, drawing on a range of emotional and intellectual resources and deep, longstanding commitments. I conclude by speculating on the kinds of policy and research agendas that might take account of both the commonalities and differences amongst 'disadvantaged schools', and what might be included in a comprehensive and systematic approach to 'doing justice'.

Comparison of corticomotor excitability during visuomotor dynamic and static tasks

The human central nervous system (CNS) has the ability to modulate its activity during the performance of different movements. Recent evidence, however, suggests that the CNS can also modulate its activity in the same movement but with increased precision during a visuomotor static task. This study aimed to extend on these findings by using transcranial magnetic stimulation (TMS) to measure the CNS during the performance of two visuomotor dynamic tasks. Twelve volunteers participated in this study, performing two separate motor tasks. Study I (“Position Tracking”) involved participants to perform a visuomotor tracking task using a dial potentiometer and matching their response icon to the computer generated tracking icon whilst holding a pincer grip. Study II (“Force Tracking”) involved participants to perform a similar visuomotor tracking task by applying or releasing pressure against a fixed force transducer. Tasks were conducted at two speeds (“slow” being one tracking cycle in 10 s; and “fast” being two tracking cycles in 10 s) and compared to a visuomotor static task at a similar muscle contraction level. Results showed corticospinal changes with significant increases (p = 0.002) in excitability demonstrated during Study I (42.3 ± 16.8%) and Study II (56.3 ± 34.2%) slow speed tasks. Moreover, significant reduction in corticospinal inhibition was also observed during both tracking tasks at slow (59.3 ± 13.7%; p = 0.001) and fast speeds (31.9 ± 12.3%; p = 0.001). The findings may provide information on the underlying physiology during the early stages of motor skill acquisition.

Energy-efficient management of data center resources for cloud computing : a vision, architectural elements, and open challenges

Cloud computing is offering utility-oriented IT services to users worldwide. Based on a pay-as-you-go model, it enables hosting of pervasive applications from consumer, scientific, and business domains. However, data centers hosting Cloud applications consume huge amounts of energy, contributing to high operational costs and carbon footprints to the environment. Therefore, we need Green Cloud computing solutions that can not only save energy for the environment but also reduce operational costs. This paper presents vision, challenges, and architectural elements for energy-efficient management of Cloud computing environments. We focus on the development of dynamic resource provisioning and allocation algorithms that consider the synergy between various data center infrastructures (i.e., the hardware, power units, cooling and software), and holistically work to boost data center energy efficiency and performance. In particular, this paper proposes (a) architectural principles for energy-efficient management of Clouds; (b) energy-efficient resource allocation policies and scheduling algorithms considering quality-of-service expectations, and devices power usage characteristics; and (c) a novel software technology for energy-efficient management of Clouds. We have validated our approach by conducting a set of rigorous performance evaluation study using the CloudSim toolkit. The results demonstrate that Cloud computing model has immense potential as it offers significant performance gains as regards to response time and cost saving under dynamic workload scenarios.

Adaptive data based neural network leader-follower control of multi-agent networks

In this paper, we propose a data based neural network leader-follower control for multi-agent networks where each agent is described by a class of high-order uncertain nonlinear systems with input perturbation. The control laws are developed using multiple-surface sliding control technique. In particular, novel set of sliding variables are proposed to guarantee leader-follower consensus on the sliding surfaces. Novel switching is proposed to overcome the unavailability of instantaneous control output from the neighbor. By utilizing RBF neural network and Fourier series to approximate the unknown functions, leader-follower consensus can be reached, under the condition that the dynamic equations of all agents are unknown. An O(n) data based algorithm is developed, using only the network’s measurable input/output data to generate the distributed virtual control laws. Simulation results demonstrate the effectiveness of the approach.