Business cycle dynamics with duration dependence and leading indicators

Durland and McCurdy [Durland, J.M., McCurdy, T.H., 1994. Duration-dependent transitions in a Markov model of US GNP growth. Journal of Business and Economic Statistics 12, 279–288] investigated the issue of duration dependence in US business cycle phases using a Markov regime-switching approach, introduced by Hamilton [Hamilton, J., 1989. A new approach to the analysis of time series and the business cycle. Econometrica 57, 357–384] and extended to the case of variable transition parameters by Filardo [Filardo, A.J., 1994. Business cycle phases and their transitional dynamics. Journal of Business and Economic Statistics 12, 299–308]. In Durland and McCurdy’s model duration alone was used as an explanatory variable of the transition probabilities. They found that recessions were duration dependent whilst expansions were not. In this paper, we explicitly incorporate the widely-accepted US business cycle phase change dates as determined by the NBER, and use a state-dependent multinomial Logit modelling framework. The model incorporates both duration and movements in two leading indexes – one designed to have a short lead (SLI) and the other designed to have a longer lead (LLI) – as potential explanatory variables. We find that doing so suggests that current duration is not only a significant determinant of transition out of recessions, but that there is some evidence that it is also weakly significant in the case of expansions. Furthermore, we find that SLI has more informational content for the termination of recessions whilst LLI does so for expansions.

Current AI in games : a review

As the graphics race subsides and gamers grow weary of predictable and deterministic game characters, game developers must put aside their “old faithful” finite state machines and look to more advanced techniques that give the users the gaming experience they crave. The next industry breakthrough will be with characters that behave realistically and that can learn and adapt, rather than more polygons, higher resolution textures and more frames-per-second. This paper explores the various artificial intelligence techniques that are currently being used by game developers, as well as techniques that are new to the industry. The techniques covered in this paper are finite state machines, scripting, agents, flocking, fuzzy logic and fuzzy state machines decision trees, neural networks, genetic algorithms and extensible AI. This paper introduces each of these technique, explains how they can be applied to games and how commercial games are currently making use of them. Finally, the effectiveness of these techniques and their future role in the industry are evaluated.

Accurately simulating the production of radiotherapy portal images using non-zero beam angles

In this study, the delivery and portal imaging of one square-field and one conformal radiotherapy treatment was simulated using the Monte Carlo codes BEAMnrc and DOSXYZnrc. The treatment fields were delivered to a humanoid phantom from different angles by a 6 MV photon beam linear accelerator, with an amorphous-silicon electronic portal imaging device (a-Si EPID) used to provide images of the phantom generated by each field. The virtual phantom preparation code CTCombine was used to combine a computed-tomography-derived model of the irradiated phantom with a simple, rectilinear model of the a-Si EPID, at each beam angle used in the treatment. Comparison of the resulting experimental and simulated a-Si EPID images showed good agreement, within \[gamma](3%, 3 mm), indicating that this method may be useful in providing accurate Monte Carlo predictions of clinical a-Si EPID images, for use in the verification of complex radiotherapy treatments.

The current context of Queensland primary teacher engagement with professional learning through professional associations

Engaging Queensland primary teachers in professional associations can be a challenge, particularly for subject-specific associations. Professional associations are recognised providers of professional learning. By not being involved in professional associations primary teachers are missing potential quality professional learning opportunities that can impact the results of their students. The purpose of the research is twofold: Firstly, to provide a thorough understanding of the current context in order to assist professional associations who wish to change from their current level of primary teacher engagement; and secondly, to contribute to the literature in the area of professional learning for primary teachers within professional associations. Using a three part research design, interviews of primary teachers and focus groups of professional association participants and executives were conducted and themed to examine the current context of engagement. Force field analysis was used to provide the framework to identify the driving and restraining forces for primary teacher engagement in professional learning through professional associations. Communities of practice and professional learning communities were specifically examined as potential models for professional associations to consider. The outcome is a diagrammatic framework outlining the current context of primary teacher engagement, specifically the driving and restraining forces of primary teacher engagement with professional associations. This research also identifies considerations for professional associations wishing to change their level of primary teacher engagement. The results of this research show that there are key themes that provide maximum impact if wishing to increase engagement of primary teachers in professional associations. However the implications of this lies with professional associations and their alignment between intent and practice dedicated to this change.

Challenges facing sustainable housing in Saudi Arabia : a current study showing the level of public awareness

Sustainable housing implementation requires strong support from the public, government and the housing industry. Lack of public awareness and understanding of the language and the meaning of sustainable housing may cause lack of public support. Salama stated that "sustainability or sustainable design is simply a rephrasing of some of the forgotten values of traditional architecture and urbanism"(Salama 2007). This exploratory paper examines public awareness of sustainable housing in Saudi Arabia. In developing countries, like Saudi Arabia, which have been experiencing a rapid rate of urbanisation, sustainable concept intervention is essential due to the scarcity of resources (Reffat 2004a). Sustainable building methods include the full use of the site design, passive solar design, natural light and ventilation. This paper reports on an exploratory survey on understanding the potential of the implementation of sustainable housing in Saudi Arabia. The main problem is that more than half of respondents were not aware of sustainable housing. Thus, one of the recommendations from the survey is to educate the public by using local media to inform people of the benefits of sustainable implementation to both new and existing housing stock.

Training clinical psychologists : The current situation and a way forward [Guest Editorial]

In the past, training in clinical psychology in Australia and overseas has been dominated by definitions of input— hours of classes or supervision and of specific components. While prospective practitioners have been required to demonstrate the acquisition of generic competencies, satisfaction of these input driven criteria has been required for both accreditation and registration. Ironically, for a discipline that prides itself on requiring empirical bases for practice and communicating those to students (Calhoun, Moras, Pilkonis, & Rehm, 1998), training criteria have been primarily derived from accepted wisdom, rather than from a sound body of data. The situation has been remarkably like that of a treatment establishing standards of fidelity before its effective components are known—an action our profession has correctly criticised in the past (Herbert & Mueser, 1992).

Monitoring identity of past, current and future : a performance management system perspective

This paper seeks to explore how organisations can effectively use performance management systems (PMS) to monitor collective identities. The monitoring of relationships between identity and an influential PMS—the balanced scorecard (BSC)—are explored. Drawing from identity and management accounting literature, this paper argues that identity products, patternings and processes are commonly positioned, monitored and interpreted through the multiple perspectives and levels of the BSC. Specifically, human, technical and organisational capital under the Learning and Growth perspective of the BSC can incorporate various identity measures that sustain the relative, distinctive and fluid nature of identities. The value of this research is to strengthen the theoretical grounds which position identity as an important dimension of organisational capital in PMS.

Managing large collections of business process models - Current techniques and challenges

Nowadays, business process management is an important approach for managing organizations from an operational perspective. As a consequence, it is common to see organizations develop collections of hundreds or even thousands of business process models. Such large collections of process models bring new challenges and provide new opportunities, as the knowledge that they encapsulate requires to be properly managed. Therefore, a variety of techniques for managing large collections of business process models is being developed. The goal of this paper is to provide an overview of the management techniques that currently exist, as well as the open research challenges that they pose.

Current affairs in British public service broadcasting : challenges and opportunities

This chapter looks at the challenges and opportunities of current affairs in British public service broadcasting

Analysis of electromagnetic forces in high voltage superconducting fault current limiters with saturated core

This paper presents a three-dimensional numerical analysis of the electromagnetic forces within a high voltage superconducting Fault Current Limiter (FCL) with a saturated core under short-circuit conditions. The effects of electrodynamics forces in power transformer coils under short-circuit conditions have been reported widely. However, the coil arrangement in an FCL with saturated core differs significantly from existing reactive devices. The boundary element method is employed to perform an electromagnetic force analysis on an FCL. The analysis focuses on axial and radial forces of the AC coil. The results are compared to those of a power transformer and important design considerations are highlighted.

Classifying external causes of injury : history, current approaches, and future directions

The International Classification of Diseases (ICD) is used to categorise diseases, injuries and external causes, and is a key epidemiological tool enabling the storage and retrieval of data from health and vital records to produce core international mortality and morbidity statistics. The ICD is updated periodically to ensure the classification remains current and work is now underway to develop the next revision, ICD-11. There have been almost 20 years since the last ICD edition was published and over 60 years since the last substantial structural revision of the external causes chapter. Revision of such a critical tool requires transparency and documentation to ensure that changes made to the classification system are recorded comprehensively for future reference. In this paper, the authors provide a history of external causes classification development and outline the external cause structure. Approaches to manage ICD-10 deficiencies are discussed and the ICD-11 revision approach regarding the development of, rationale for and implications of proposed changes to the chapter are outlined. Through improved capture of external cause concepts in ICD-11, a stronger evidence base will be available to inform injury prevention, treatment, rehabilitation and policy initiatives to ultimately contribute to a reduction in injury morbidity and mortality.