Well-conditioned configurations of fault-tolerant manipulators

Fault-tolerant motion of redundant manipulators can be obtained by joint velocity reconfiguration. For fault-tolerant manipulators, it is beneficial to determine the configurations that can tolerate the locked-joint failures with a minimum relative joint velocity jump, because the manipulator can rapidly reconfigure itself to tolerate the fault. This paper uses the properties of the condition numbers to introduce those optimal configurations for serial manipulators. The relationship between the manipulator's locked-joint failures and the condition number of the Jacobian matrix is indicated by using a matrix perturbation methodology. Then, it is observed that the condition number provides an upper bound of the required relative joint velocity change for recovering the faults which leads to define the optimal fault-tolerant configuration from the minimization of the condition number. The optimization problem to obtain the minimum condition number is converted to three standard Eigen value optimization problems. A solution is for selected optimization problem is presented. Finally, in order to obtain the optimal fault-tolerant configuration, the proposed method is applied to a 4-DoF planar manipulator.

Association between perception of fault for the crash and function, return to work and health status 1 year after road traffic injury: a registry-based cohort study

Objectives To establish the association between the patient's perception of fault for the crash and 12-month outcomes after non-fatal road traffic injury.Setting Two adult major trauma centres, one regional trauma centre and one metropolitan trauma centre in Victoria, Australia.Participants 2605 adult, orthopaedic trauma patients covered by the state's no-fault third party insurer for road traffic injury, injured between September 2010 and February 2014.Outcome measures EQ-5D-3L, return to work and functional recovery (Glasgow Outcome Scale—Extended score of upper good recovery) at 12 months postinjury.Results After adjusting for key confounders, the adjusted relative risk (ARR) of a functional recovery (0.57, 95% CI 0.46 to 0.69) and return to work (0.92, 95% CI 0.86 to 0.99) were lower for the not at fault compared to the at fault group. The ARR of reporting problems on EQ-5D items was 1.20–1.35 times higher in the not at fault group. Conclusions Patients who were not at fault, or denied being at fault despite a police report of fault, experienced poorer outcomes than the at fault group. Attributing fault to others was associated with poorer outcomes. Interventions to improve coping, or to resolve negative feelings from the crash, could facilitate better outcomes in the future.

Reactive system model for building fault-tolerant distributed applications

The development of fault-tolerant computing systems is a very difficult task. Two reasons contributed to this difficulty can be described as follows. The First is that, in normal practice, fault-tolerant computing policies and mechanisms are deeply embedded into most application programs, so that these application programs cannot cope with changes in environments, policies and mechanisms. These factors may change frequently in a distributed environment, especially in a heterogeneous environment. Therefore, in order to develop better fault-tolerant systems that can cope with constant changes in environments and user requirements, it is essential to separate the fault tolerant computing policies and mechanisms in application programs. The second is, on the other hand, a number of techniques have been proposed for the construction of reliable and fault-tolerant computing systems. Many computer systems are being developed to tolerant various hardware and software failures. However, most of these systems are to be used in specific application areas, since it is extremely difficult to develop systems that can be used in general-purpose fault-tolerant computing. The motivation of this thesis is based on these two aspects. The focus of the thesis is on developing a model based on the reactive system concepts for building better fault-tolerant computing applications. The reactive system concepts are an attractive paradigm for system design, development and maintenance because it separates policies from mechanisms. The stress of the model is to provide flexible system architecture for the general-purpose fault-tolerant application development, and the model can be applied in many specific applications. With this reactive system model, we can separate fault-tolerant computing polices and mechanisms in the applications, so that the development and maintenance of fault-tolerant computing systems can be made easier.

The study into fault tolerance based on rollback-recovery for clusters

The provision of fault tolerance is an important aspect to the success of distributed and cluster computing. Through this research , a transparent, autonomic and efficient fault tolerant facility was designed and implemented; thereby relieving the burden of a user having to handle and react to the failure of an application.

All the animals are gone? The politics of contemporary hunter arcade games.

Recent proliferation and popularity of personal computer and console games has meant that scholarship around video arcade games has been largely ignored. Arcade games had their halcyon days during the 1970s and 1980s when 'Space Invaders', 'Pong' and 'Donkey Kong' were household names. The inception of scholarship into games occurred in the 1990s; a time when arcade games were writ small in the cultural imagination, at least compared to the newer home computer and video games. Thus in games theory they are typically discussed only in terms of their role as antecedents to their more popular kin. Moreover, they seem innocuous because they are so publicly accessible. Against this assumption, and lack of scholarship, this paper explores a selection of contemporary arcade games which we describe as 'hunting' games. Arcade hunting games are first-person shooter (FPS) involving one or more players shooting simulated wild animals. They are commonly situated in cinema foyers, hotels, and family entertainment centres. However, despite a presumption of institutional moderation afforded by the public accessibility of these spaces, this paper argues that this genre works through a range of political modalities that require more scholarly consideration than currently given.

A comparative analysis of directors' duty of care, skill and diligence in South Africa and in Australia

The South African and Australian law regarding directors' duty of care, ski ll and diligence were influenced considerably by English precedent of the late 1800s and early 19005. Originally both jurisdictions adopted a conservative approach towards directors' duty of care, skill and diligence. This resulted in very low standards of care, skill and diligence expected of directors. In Australia, the standards of care and diligence expected of directors changed drastically with the case of Daniels v Anderson, where objective standards were used to determine a breach of directors' duty of care and diligence, and when objective standards of care and diligence were introduced in Australian corporations legislation. In this article it is submitted that if the opportunity arose for a South African court to consider whether a director is in breach of his or her common law duty of care, skill and diligence, the form of fault that will be required will be negligence as judged against the standards of a reasonable person. This means that in actual fact objective standards of care and diligence are expected of directors in South Africa. Although section 76(3) of the South African Companies Act 71 of 2008 does not introduce purely objective standards of care, skill and diligence, the section is defended in this article. It is pointed out that encouraging emerging entrepreneurs to become directors of South African companies provides justification for keeping subjective elements as part of the test to determine whether a director was in breach of his or her statutory duty of care, skill and diligence.

Multiple actuator fault tolerance for static nonlinear systems based on minimum velocity jump

Static nonlinear systems are common when the model of the kinematics of mechanical or civil structures is analyzed for instance kinematics of robotic manipulators. This paper addresses the maximum effort toward fault tolerance for any number of the locked actuators failures in static nonlinear systems. It optimally reconfigures the inputs via a mapping that maximally accommodates the failures. The mapping maps the failures to an extra action of healthy actuators that results to a minimum jump for the velocity of the output variables. Then from this mapping, the minimum jump of the velocity of the output is calculated. The conditions for a zero velocity jump of the output variables are discussed. This shows that, when the conditions of fault tolerance are maintained, the proposed framework is capable of fault recovery not only at fault instances but also at the whole output trajectory. The proposed mapping is validated by three case studies.

Optimal fault tolerant Jacobian matrix generators for redundant manipulators

The design of locally optimal fault-tolerant manipulators has been previously addressed via adding constraints on the bases of a desired null space to the design constraints of the manipulators. Then by algebraic or numeric solution of the design equations, the optimal Jacobian matrix is obtained. In this study, an optimal fault-tolerant Jacobian matrix generator is introduced from geometric properties instead of the null space properties. The proposed generator provides equally fault-tolerant Jacobian matrices in R3 that are optimally fault tolerant for one or two locked joint failures. It is shown that the proposed optimal Jacobian matrices are directly obtained via regular pyramids. The geometric approach and zonotopes are used as a novel tool for determining relative manipulability in the context of fault-tolerant robotics and for bringing geometric insight into the design of optimal fault-tolerant manipulators.

Rape in Victoria as a crime of absolute liability : a departure from both precedent and progressivism

In recent decades, a disturbing trend has emerged in Victoria and elsewhere that has witnessed the emergence of statutory rules that accord preferential treatment to prosecutors and complainants in instances where allegations of rape are made. This article examines not only the manifestations of such treatment in the form of Victorian crime legislation, but the means by which the statutory crime of rape in Victoria has been transformed into an offence which, though technically one of mens rea, can effectively be prosecuted as an offence of absolute liability. The piece concludes with a discussion of the likely reasons for this trend as well as the implications of allowing such a serious offence to be prosecuted as one of absolute liability.

Lessons in aiding journalism and democracy: a study of Australian educators working in the Asia Pacific region

 This paper examines assumptions about democracy and the role of media held by journalism educators working outside Australia, and the extent to which those assumptions influence teaching styles, regardless of the maturity of the political systems in the nations in question. This paper looks at the work emerging from academics Beate Josephi, Barbie Zelizer, John Nerone, Cherian George and Silvio Waisbord, who argue in Journalism (2012) that there needs to be a change to the understanding by journalism scholars of the central place of journalism in democracy because that view is not global in its perspective. This paper specifically considers Zelizer’s point that “much of the scholarly world in the West – and specifically in the United States – depends directly or indirectly on the presumption of democracy and its accoutrements”. The researcher asks, “what can we learn about our Australian perspective on teaching journalism in the developing world where there may not, yet, be an operating democracy or a form of democracy that replicates the Western liberal model?”

The restorative role of apology in resolving medical disputes: Lessons from Chinese legal culture

This article is the first exploration of the Chinese notion of apology from a comparative legal perspective. By reviewing the significance of apology in the context of Chinese culture, the article presents a three-dimensional structure of apology that, in contrast to the understanding the research community now has, defines acknowledgement of fault, admission of responsibility, and offer of reparation as three essential elements of an apology. It is the combination of these three elements that enables apology to serve as a form of reparation. The article further places the three-dimensional apology in the context of the Chinese concept of "the relations of humanity," arguing that an apology accompanying admission of fault and responsibility may help to restore the harmony of relations and, by so doing, resolve medical disputes positively.

Is a 24 hour ban such a bad thing?

A key element in Australian policing in recent years is the growth of police-imposed discretionary summary justice. The rise and impact of on-the-spot fines, infringement notices, exclusion orders and move-on powers enable police-initiated resolutions and punishments to be imposed, often without legal or judicial intervention. These operational policing mechanisms reflect underlying pressures to reduce costs, ease the burden on the court system, and speed up the decision-making process, but when viewed from a human rights perspective the potential consequences are significant. Focusing on the legislative development of banning notices in Victoria, this article highlights the impact of such a police-imposed punishment upon individual due process procedural protections. Banning notices deny the recipient the right to conduct a defence, undermine the presumption of innocence, and conflate notions of pre-emption and punishment. The rhetoric upon which the banning notice legislation is predicated obviates meaningful scrutiny of the diminution of individual rights that are implicit in its enactment. A perceived ‘need’ to control disorder and ‘re-balance’ justice to prioritise community protection is used to legitimise any consequential impact upon the principles of criminal law, due process and human rights.

The tax treatment of employee stock options : generous to a fault

In the 2000 budgets, both the federal and Ontario governments introduced changes to the tax treatment of employee stock options for the explicit purpose of making their tax treatment in Canada similar to or more favourable than that in the United States. The federal budget added a deferral, similar to that currently applicable to options granted by Canadian-controlled private corporations, for up to $100,000 per year of public company stock options. The Ontario budget introduced an exemption from tax for employees involved in research and development on the first $100,000 per year of employee benefits arising on the exercise of qualified stock options or on eligible capital gains arising from the sale of shares acquired by the exercise of eligible stock options. These proposals reflect the apparent acceptance by the two governments that there is a “brain drain” from Canada to the United States of knowledge workers in the “new” economy and that reductions in Canadian taxes should stem this drain. In the author’s view, the tax treatment of employee stock options, even without these changes, is overly generous. Both the federal and provincial proposals ignore the fact that most employee stock options are taxed more favourably in Canada than in the United States in any event. In particular, most employee stock option benefits in Canada are taxed at capital gains tax rates, whereas in the United States most are taxed at full rates. While the US Internal Revenue Code does provide capital gains tax treatment for certain employee stock option benefits, a number of preconditions must be met. Most important, the shares acquired pursuant to the options must be held for a minimum of one year after the option is exercised. In addition, there are monetary limits on the amount of options that qualify for capital gains treatment. In Canada, there are generally no holding period requirements or monetary limits that apply in order for the option holder to benefit from capital gains tax rates. Empirical evidence indicates that the vast majority of employees in the United States exercise their options and immediately sell the shares acquired. These “cashless exercises” do not benefit from capital gains treatment in the United States, whereas similar cashless exercises in Canada generally do. This empirical evidence suggests not only that the 2000 budget proposals are unwarranted, but also that the existing treatment of employee stock options in Canada is already more generous than that in the United States. This article begins with a theoretical “benchmark” for the taxation of employee stock options. The author suggests that employee stock options should be treated in the same manner as other income from employment. In theory, the value of the benefit should be included in income when the option is granted or vests. However, owing to the practical difficulty of valuing employee stock options, the theoretical benchmark proposed is that the value of the benefit (the difference between the fair market value of the shares acquired and the strike price under the option) be taxed when the shares are acquired, and the employer be entitled to a corresponding deduction. The employee stock option rules in Canada and the United States are then compared and contrasted with each other and the benchmark treatment. The article then examines the arguments that have been made for favourable treatment of employee stock options. Included in this critique is a review of the recent empirical work on the Canadian brain drain. Empirical studies suggest that the brain drain—if it exists at all—is small and that, despite what many newspapers and right-wing think-tanks would have us believe, lower taxes in the United States are not the cause. One study, concluding that taxes do have an effect on migration, suggests that even if Canada adopted a tax system identical to that in the United States, the brain drain would be reduced by a mere 10 percent. Indeed, even if Canada eliminated income tax altogether, it would not stop the brain drain. If governments here want to spend money in order to stem the brain drain, they should focus on other areas. For example, Canada produces fewer university graduates in the fields of mathematics, sciences, and engineering than any other G7 country except Italy. The short supply of university graduates in these fields, the apparent loss of top-calibre academics to US
universities, and the consequent lower levels of university research in these areas (an important spawning ground for new ideas in the “new” knowledge-based economy) suggest that Canada may be better served by devoting more resources to its university institutions, particularly in post-graduate programs, rather than continuing the current trend of budget cuts that universities have endured and may further endure if taxes are reduced.
As far as employee stock options are concerned, if Canada does want to look to the United States for guidance on tax reform (which it seems to do with increasing frequency of late), it should adopt the US rules applicable to nonstatutory options, which are close to the proposed benchmark treatment. In the absence of preferential tax treatment, employee stock options would still be included in compensation packages provided that there were sound business reasons for their use. No persuasive evidence has been put forward that the use of stock options, in the absence of tax incentives, is suboptimal. Indeed, the US experience suggests quite the opposite.