Formations of robotic swarm: an artificial force based approach

Cooperative control of multiple mobile robots is an attractive and challenging problem which has drawn considerable attention in the recent past. This paper introduces a scalable decentralized control algorithm to navigate a group of mobile robots (swarm) into a predefined shape in 2D space. The proposed architecture uses artificial forces to control mobile agents into the shape and spread them inside the shape while avoiding intermember collisions. The theoretical analysis of the swarm behavior describes the motion of the complete swarm and individual members in relevant situations. We use computer simulated case studies to verify the theoretical assertions and to demonstrate the robustness of the swarm under external disturbances such as death of agents, change of shape etc. Also the performance of the proposed distributed swarm control architecture was investigated in the presence of realistic implementation issues such as localization errors, communication range limitations, boundedness of forces etc.

The effects of improved strength on obstacle negotiation in community-living older adults

Poor mobility has been associated with age-related deterioration in muscle strength. While previous work has examined the effects of improved strength on level walking, we have quantified the effects of a resistance-training program on obstructed gait tasks using biomechanical-dependent measures. Forty-five community-dwelling participants aged 62 years or older were randomised to either a control (n=16) or experimental group (n=29). The experimental subjects exercised for 24 weeks on a progressive resistance-training program designed to improve lower body strength. Dynamic strength was assessed at weeks 0 and 24 as well as specific laboratory gait kinetics and kinematics during stepping over an obstacle and negotiation of a raised surface set at 10, 20 and 30% of each subject's leg length.

"To GAAR or not to GAAR-that is the question:" Canadian and Australian attempts to combat tax avoidance

In both Canada and Australia the relevant governments found their initial legislative attempts to combat tax avoidance to be ineffective. In time in each country it was concluded that the respective general avoidance provisions were of limited application and avoidance provisions were of limited application and ineffective to combat the sophisticated tax avoidance schemes promoted by tax advisers. In Canada it was determined that Income Tax Act, R.S.C 1985, s. 245(1) would be repealed and replaced with a general anti-avoidance rule ('GAAR') contained in a new s. 245 ITA. The Australian government similarly decided to replace Income Tax Assessment Act, Cth. 1936, s. 260 with a new general anti-avoidance measure, Part IVA ITAA. This article compares and contrasts the Canadian and Australian GAARs. Through the evaluation of each regime the article seeks to identify which model is most effective. It will be sen which model is most effective. It will be seen that both regimes have some features that are preferable to the other and thus both GAARs might be improved by incorporating aspects of the other anti-avoidance model.

Multi-jurisdictional merger review procedures - a better way

Corporate mergers whose effects transcend national borders have faced increasing regulation over the past few decades as more jurisdictions have developed merger laws and imposed pre-merger notification requirements. The level of regulatory response to multi-jurisdictional mergers is likely to continue to increase as even more jurisdictions contemplate the introduction of competition laws. This level of regulation now goes beyond that required to protect national economies from potentially harmful mergers and has seen burgeoning costs to business, regulators and, ultimately, the public. In recognition of this, the relatively newly formed International Competition Network has placed merger regulation at the forefront of its agenda for greater harmonisation and cooperation in competition law. This has seen, over the past three years, the development of a set of guiding principles and recommended practices for merger notification procedures designed to reduce the regulatory burden. This article evaluates these recommendations and discusses areas for further reform.

Promoting innovation in university teaching against the tide of centralised control and institutional risk avoidance

Over the last m'o decades, university systems world-wide have been subject to government initiated, top-down restructures in the name of greater effectiveness, accountability and quality. Within this timefrome, government interest in university teaching has increased, and innovation and responsiveness in teaching have been increasingly prioritised by both government and university policies. AcademiC interest in the teaching has also increased. and much research and discussion has focused on defining teaching as a source of scholarship and expounding its role in the promotion of innovation, and in the recognition and rewarding of teaching work. In this paper, I draw on a study of academics' views, which I have reported at previous AARE conferences and elsewhere, to raise questions about recent and ongoing developments in the work environment of university educators.l raise the possibility that systems and processes whose express purpose is to facilitate and support university educators' efforts to improve teaching are, in fact. inhibiting innovative practice by institutionalising an aversion to risk that is anathema to innovation.

Family member presence during resuscitation in the emergency department: an Australian perspective

Objective: The practice of family member presence during resuscitation in the ED has attracted widespread attention over the last few decades. Despite the recommendations of international organizations, clinical staff remain reluctant to engage in this practice in many EDs. This paper separates the evidence from opinion to determine the current state of knowledge about this practice.

Methods: A search strategy was developed and used to locate research based publications, which were subsequently reviewed for the strength of evidence providing the basis for recommendations.

Results: The literature was examined to reveal what patients and their family members want; the outcomes of family presence during resuscitation for patients and their family members; staff views and practices regarding family presence during resuscitation. Findings suggest that providing the opportunity to be with their critically ill family member is both important to and beneficial for families, however, disparity in staff views has been identified as a major obstacle to family presence during resuscitation. Examination of published guidelines and staff practices described in the literature revealed consistent elements.

Conclusion: Although critics point to the lack of rigour in this body of literature, the current state of knowledge suggests merit in pursuing future research to examine and measure effects of family member presence during resuscitation on patients, family members and healthcare providers.

Control of lead and trail limbs during obstacle crossing following stroke

Background and Purpose. Obstacle crossing is compromised following stroke. The purpose of this study was to quantify modifications during obstacle clearance following stroke.

Subjects. Twelve subjects with stroke and 12 subjects without stroke participated in the study.

Methods. Kinematic variables were measured while participants crossed a 4-cm-high obstacle. Subjects with stroke walked at a self-selected speed; subjects without stroke walked at a comparable speed and at a self-selected speed.

Results. Several modifications were observed following stroke with both groups walking at self-selected speeds. The affected lead limb was positioned closer to the obstacle before crossing. Affected trail-limb clearance over the obstacle was reduced. Both affected and unaffected lead and trail limbs landed closer to the obstacle after clearance. Swing time was increased in the affected lead limb after obstacle clearance. Fewer modifications were detected at matched walking speed; the trail limb still landed closer to the obstacle.

Discussion and Conclusion. Modifications during obstacle crossing following stroke may be partly related to walking speed. The findings raise issues of safety because people with stroke demonstrated reduced clearance of a 4-cm obstacle and limb placement closer to the obstacle after clearance.

New learning networks and their invisible students : policy as simulation or the avoidance game?

Within a climate of policy hysteria, it is often claimed that a 'preoccupation with performance' develops, focussing on individual success stories, resulting in 'fad-like waves of adoption and abandonment'. Within this increasing pace and intensity of reform, new networks are formed and new relationships developed, with key players taking on new forms of identity to morph into the constantly changing policy climate. Despite continued evidence of young people's pathways from school being more like mosaic than linear, new policy still seeks to define and limit the possible lines of flight and trajectories, closely managing the education and training of young people at risk. In Victoria, the major policy initiative has involved the establishment of LLENs, the local all purpose solution to young people who might not be sticking to the linear policy pathway. So are we involved in 'an avoidance game', filling up the post compulsory policy space with more and more policies, which in fact seek to continue to regulate and constrain young people, rather than supporting them? This paper interrogates the policies and practices which have created the learning networks, of the SGR LLEN through policy analysis and case studies.

Patients' experiences of cardiology procedures using minimal conscous sedation

Aim: The study's purpose was to describe patients' experiences of minimal conscious sedation during diagnostic and interventional cardiology procedures.

Methods: Over a 6-week period, 119 consecutive patients (10% of annual throughput) from a major metropolitan hospital in Melbourne, Australia, were interviewed using a modified version of the American Pain Society Patient Outcome Questionnaire. Patients identified pain severity using a 10-point visual analogue scale and rated their overall comfort on a 6-point Likert scale ranging from very comfortable to very uncomfortable.

Results: Patients were aged 67.6 years (standard deviation 11.1), 70.8% were male, and the mean body mass index was 27.7 (standard deviation 4.8). Patients underwent diagnostic coronary angiography (67.5%), percutaneous coronary interventions (13.3%), or combined procedures (19.2%). Most patients (65%) were comfortable in the context of low-dose conscious sedation. Slight discomfort was reported by 26% of patients; 9% reported feeling uncomfortable primarily as a result of a combination of musculoskeletal pain, angina, and vasovagal symptoms experienced during the procedure. There was significant correlation (rho = .25, P = .01) between procedure length and patients' report of overall comfort, suggesting longer procedures were less comfortable for patients.

Conclusions: The minimal sedation protocol was effective for the majority of patients; however, 9% of patients experienced significant discomfort related to preexisting conditions, highlighting the need for individual patient assessment before, during, and after the procedure.