Robust extended kalman filter applied to location tracking and trajectory prediction for PCS networks

Provisioning of real-time multimedia sessions over wireless cellular network poses unique challenges due to frequent handoff and rerouting of a connection. For this reason, the wireless networks with cellular architecture require efficient user mobility estimation and prediction. This paper proposes using robust extended Kalman filter (REKF) as a location heading altitude estimator of mobile user for next cell prediction in order to improve the connection reliability and bandwidth efficiency of the underlying system. Through analysis we demonstrate that our algorithm reduces the system complexity (compared to existing approach using pattern matching and Kalman filter) as it requires only two base station measurements or only the measurement from the closest base station. Further, the technique is robust against system uncertainties due to inherent deterministic nature in the mobility model and more effective in comparison with the standard Kalman filter.

Playing with time: history and the extended present

In this paper we consider how the concept of time is developed in schools. We argue that the teaching and learning of history (despite the emergence of the new history in the 1970s) is still taught and learnt with a temporal bias and it is often positioned in the past. So too, history/SOSE1 student-teachers are exposed to temporal bias in their tertiary education (as is evidenced in ‘Arts Faculty’ history courses). We suggest that there needs to be greater connectedness and balance between the dimensions of time in the teaching of SOSE with specific reference to the teaching of history and futures perspectives. We offer a new conceptualisation of history which we refer to as ‘history as the extended present’ this conceptualisation positions history in multiple temporal domains (the past, present and possible, probable and preferable futures) and emphasises the relevance of teaching and learning history to students life worlds.

Creative marketing : an extended metaphor for marketing in a new age

Creative Marketing challenges mainstream marketing thinking and draws from a diverse range of disciplines in order to inspire entrepreneurial thinking and practice among those marketers who wish to push the boundaries of knowledge.

Technologies and considerations for developing internet and multiplayer computer games: a tutorial (extended abstract)

Games are universal and probably as old as humankind. Today the development of computer technology, especially the development of fast networks and the Internet, brings games a faster growth than ever before. Game design and development is now a fast-growing entertainment field, with a lot to offer professionally and creatively. In fact, from IT professional’s point of view, creating computer games provides us with all the usual technical challenges associated with software development, such as requirement analysis, architectural design, rapid prototyping, HCI, parallel and distributed processing, code reuse, programming, performance evaluation, testing and maintenance. It also provides challenges on other exciting aspects, such as storyboarding, screenplays, illustration, animation, sound effects, music, and social impact. By developing a computer game from start to finish, one would be able to acquire multi-disciplinary knowledge to become an IT professional for the modern era.

Body composition changes, metabolic fuel use and energy expenditure during extended fasting in subantarctic fur seal (Arctocephalus tropicalis) pups at Amsterdam Island

The fasting metabolism of 71- to 235-d-old subantarctic fur seal (Arctocephalus tropicalis) pups from Amsterdam Island, southern Indian Ocean, was investigated during the long foraging trips of their mothers. Body lipid reserves were proportionally greater in female than male pups and higher in postmoult (37%) than premoult (10%) animals. The mass-specific rate of mass loss did not differ between the sexes but was lower than observed in other species. Daily mass loss was estimated to 56% fat, 10% protein, and 34% water. The rate of protein catabolism (15 g d⁻¹) was negatively related to the size of initial lipid stores and accounted for 9% (±1%) of total energy expenditure. However, body composition changes during the fast were not equal between the sexes, with females relying more on protein catabolism than males (11% and 5% of total energy expenditure, respectively). Energy expenditure (270 kJ kg⁻¹ d⁻¹) and metabolic water production (11.5 mL kg⁻¹ d⁻¹) rates are the lowest reported for an otariid species. These results suggest that subantarctic fur seal pups greatly reduce activity levels to lower energy expenditure in addition to adopting protein-sparing metabolic pathways in order to survive the extreme fasts they must endure on Amsterdam Island.

Extended cutting angle method of global optimization

Methods of Lipschitz optimization allow one to find and confirm the global minimum of multivariate Lipschitz functions using a finite number of function evaluations. This paper extends the Cutting Angle method, in which the optimization problem is solved by building a sequence of piecewise linear underestimates of the objective function. We use a more flexible set of support functions, which yields a better underestimate of a Lipschitz objective function. An efficient algorithm for enumeration of all local minima of the underestimate is presented, along with the results of numerical experiments. One dimensional Pijavski-Shubert method arises as a special case of the proposed approach.

A new distributed power control formula in CDMA mobile networks

The paper presents a new fully distributed uplink power control method for CDMA systems. The power control algorithm calculates explicitly and assigns directly the desired mobile transmit powers achieving both maximum Carrier-to-Interference Ratio at the base station and minimum mobile energy consumption. Compared with the commonly known iterative power control algorithms, the direct assignment method is easier to implement and more power efficient.

Risk assessment of child-victim sex offenders for extended supervision in New Zealand

Recently enacted legislation in New Zealand, the Parole (Extended Supervision) Amendment Act 2004, allows for the imposition of up to 10 years of supervision in the community for child-victim sex offenders following their release from prison. The Act requires reports to be written specifically assessing the risk of sexual re-offending against children. This study examined the application of actuarial measures used by the New Zealand Department of Corrections in these assessments, including a computer-scored instrument based on static factors (the Automated Sexual Recidivism Scale; ASRS) and a clinically-based judgement of dynamic risk factors (the SONAR). It was expected that a conservative approach would be taken in making recommendations for or against extended periods of supervision, such that a high score on either measure would predict a recommendation for extended supervision. It was found, however, that a more individualized approach was often taken, whereby a baseline assessment of risk as predicted by the ASRS was adjusted by clinicians based on SONAR ratings. Implications for the practice of risk assessment in sexual re-offending are discussed.

Extended supervision of sexual offenders in Australia and New Zealand : differences in implementation across jurisdictions

Australia and New Zealand have joined the movement of many Western societies in recent years to address a perceived gap in public safety by passing legislation allowing for extended supervision of sex offenders in the community after their release from prison. The Australian State of Victoria passed a law similar to that of New Zealand, and both laws have now been in effect for a similar period of time. Yet despite having comparable laws and approximately comparable base populations, there have been 145 extended supervision orders imposed in New Zealand and 20 such orders in Victoria. This article examines the differences in implementation and the underlying procedures used in the two jurisdictions to understand these very different outcomes. Implications for professional practice, ethics, public safety, and policy development are discussed.

Risk assessment of sexual offenders for extended supervision orders in New Zealand : basic principles and current practice

A growing number of jurisdictions in North America, the United Kingdom, and Australasia have enacted legislation allowing for special sentencing, civil commitment, and community supervision options for high risk sexual offenders. In New Zealand, one example of this concern for public protection is the Parole (Extended Supervision) Amendment Act 2004, which provides for additional supervision of sexual offenders with child victims for up to 10 years after their release from prison. Recent experience with expert evidence and judicial decision making in such cases suggests that those involved in the process might benefit from a more thorough understanding of the current state of sexual offender risk assessment that can be provided by mental health professionals.

Short term reoffending by child victim sex offenders in New Zealand : a comparison of those with and without extended supervision

Sexual offenders with child victims in New Zealand who are considered at high risk for reoffending are subject to an Extended Supervision Order. This allows for a period of supervision of up to ten years following release to the community. The present study examined 89 offenders given Extended Supervision Orders over the 33 month period since the legislation was enacted. All types of reoffending resulting in criminal convictions by this group were included. A matched sample of sexual offenders with child victims released prior to this legislation and a sample of offenders judged to be lower risk were compared to those under extended supervision. Offenders under extended supervision reoffended faster and at a higher rate for both sexual and general offences than those deemed lower risk, but at a lower rate than pre-extended supervision high risk offenders. The relationship between specialist treatment programme attendance and completion, actuarial risk level, and recidivism in the extended supervision sample were also investigated. These variables were found not to be significant predictors of sexual recidivism.