Efficient update and retrieval of objects in a multiresolution geospatial database

Many emerging applications benefit from the extraction of geospatial data specified at different resolutions for viewing purposes. Data must also be topologically accurate and up-to-date as it often represents real-world changing phenomena. Current multiresolution schemes use complex opaque data types, which limit the capacity for in-database object manipulation. By using z-values and B+trees to support multiresolution retrieval, objects are fragmented in such a way that updates to objects or object parts are executed using standard SQL (Structured Query Language) statements as opposed to procedural functions. Our approach is compared to a current model, using complex data types indexed under a 3D (three-dimensional) R-tree, and shows better performance for retrieval over realistic window sizes and data loads. Updates with the R-tree are slower and preclude the feasibility of its use in time-critical applications whereas, predictably, projecting the issue to a one-dimensional index allows constant updates using z-values to be implemented more efficiently.

International evaluation of current and future requirements for environmental engineering education

The field of environmental engineering is developing as a result of changing environmental requirements. In response, environmental engineering education (E3) needs to ensure that it provides students with the necessary tools to address these challenges. In this paper the current status and future development of E3 is evaluated based on a questionnaire sent to universities and potential employers of E3 graduates. With increasing demands on environmental quality, the complexity of environmental engineering problems to be solved can be expected to increase. To find solutions environmental engineers will need to work in interdisciplinary teams. Based on the questionnaire there was a broad agreement that the best way to prepare students for these future challenges is to provide them with a fundamental education in basic sciences and related engineering fields. Many exciting developments in the environmental engineering profession will be located at the interface between engineering, science, and society. Aspects of all three areas need to be included in E3 and the student needs to be exposed to the tensions associated with linking the three.

Changing abundance of elephants and willingness to pay for their conservation

This paper explores the way in which the stated willingness to pay for the conservation of Asian elephants in Sri Lanka varies with hypothetical variations in their abundance. To do that, it relies on results from a sample of residents of Colombo. The willingness to pay function is found to be unusual. It increases at an increasing rate for hypothetical reductions in the elephant population compared to its current level (a level that makes the Asian elephant endangered) and also increases at a decreasing rate for increases in this population from its current level. Rational explanations are Oven for this relationship. The relationship is, however, at odds with relationships suggested in some of the literature for total economic value as a function of the abundance of a wildlife species. It is suggested that willingness to pay for conservation of a species rationally includes a strategic element and may not always measure the total economic value of it species. Nevertheless. willingness to pay is still policy relevant in such cases. (c) 2005 Elsevier Ltd. All rights reserved.

Capacity limits for the detection of changing visual features

Capacity limits in visual attention have traditionally been studied using static arrays of elements from which an observer must detect a target defined by a certain visual feature or combination of features. In the current study we use this visual search paradigm, with accuracy as the dependent variable, to examine attentional capacity limits for different visual features undergoing change over time. In Experiment 1, detectability of a single changing target was measured under conditions where the type of change (size, speed, colour), the magnitude of change, the set size and homogeneity of the unchanging distractors were all systematically varied. Psychometric function slopes were calculated for different experimental conditions and ‘change thresholds’extracted from these slopes were used in Experiment 2, in which multiple supra-threshold changes were made, simultaneously, either to a single or to two or three different stimulus elements. These experiments give an objective psychometric paradigm for measuring changes in visual features over time. Results favour object-based accounts of visual attention, and show consistent differences in the allocation of attentional capacity to different perceptual dimensions.

The Coefficient of Variance as an index of L2 lexical processing skill

The Coefficient of Variance (mean standard deviation/mean Response time) is a measure of response time variability that corrects for differences in mean Response time (RT) (Segalowitz & Segalowitz, 1993). A positive correlation between decreasing mean RTs and CVs (rCV-RT) has been proposed as an indicator of L2 automaticity and more generally as an index of processing efficiency. The current study evaluates this claim by examining lexical decision performance by individuals from three levels of English proficiency (Intermediate ESL, Advanced ESL and L1 controls) on stimuli from four levels of item familiarity, as defined by frequency of occurrence. A three-phase model of skill development defined by changing rCV-RT.values was tested. Results showed that RTs and CVs systematically decreased as a function of increasing proficiency and frequency levels, with the rCV-RT serving as a stable indicator of individual differences in lexical decision performance. The rCV-RT and automaticity/restructuring account is discussed in light of the findings. The CV is also evaluated as a more general quantitative index of processing efficiency in the L2.

Mental health nursing standards and practice indicators for Australia: a review of current literature

There are many changes and challenges facing the mental health care professional working in Australia in the 21st Century. Given the significance of their number and the considerable extent to which care is delivered by them, mental health nurses in particular must be at the forefront of the movement to enhance and improve mental health care. Mental health nurses in Australia must not only keep up with the changes, we should be setting the pace for others across the profession worldwide. The increasingly complex field of mental health nursing demands nurses who are not only equipped to face the challenges but are confident in doing so. Definitive guidelines for practice, clear expectations regarding outcomes and specific means by which to evaluate both practice and outcomes are vital. Strengthening the role and vision of mental health nursing so that there is clarity about both and highlighting core values by which to perform will enable us to become focused on our future and what we can expect to both give to and receive from our chosen profession and how we can, and do, contribute to mental health care. The role of the mental health nurse is undergoing expansion and there are new hurdles to overcome along with the new benefits this brings. To support this, nationally adopted, formalised standards of practice and means by which to measure these, i.e., practice indicators formerly known as clinical indicators, are required. It is important to have national standards and practice indicators because of the variances in the provision of mental health across Australia – different legislation regarding mental health policies and processes, different nursing registration bodies and Nursing Councils, for example – which create additional barriers to cohesion and uniformity. Improvements in the practice of mental health nursing lead to benefits for consumer outcomes as well as the overall quality of mental health care available in Australia. The emphasis on rights-based care, particularly consumer and carer rights, demands evidence-based, up-to-date mental health care delivered by competent, capable professionals. Documented expectations for performance by nurses will provide all involved with yardsticks by which to evaluate outcomes. Flowing on from these benefits are advances in mental health care generally and enhancements to Australia’s reputation and position within the health care arena throughout the world. Currently, the ‘Standards for Practice’ published by the Australian New Zealand College of Mental Health Nurses (ANZCMHN) in 1995 and the practice indicators developed by Skews et al. (2000) provide a less formal guide for mental health nurses working in Australia. While these earlier standards and practice indicators have played some role in supporting mental health nurses they have not been nationally or enthusiastically adopted and there are a multitude of reasons for this. This report reviews the current literature available on practice indicators and standards for practice and describes an evidence-based rationale as to why a review and renewal of these is required and why it is important, not just for mental health nurses but to the field of mental health in general. The term ‘practice indicator’ is used, except where a quotation utilises ‘clinical indicator’, to more accurately reflect the broad spectrum of nursing roles, i.e. not all mental health nursing work involves a clinical role.