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We investigate the capacity of various ISI channels with additive white Gaussian noise. Previous papers showed a
minimum Eb/N0 of -4.6 dB, 3 dB below the capacity of a flat
channel, is obtained using water pouring capacity formulas for the 1 + D channel. However, these papers did not take into account that the channel power gain can be greater than one when water pouring is used. We present a generic power normalisation method of the channel frequency response, namely peak bandwidth normalisation, to facilitate the fair capacity comparison of various ISI channels. Three types of ISI channel, i.e., adder channels,
RC channels and magnetic recording channels, are examined.
By using our channel power gain normalisation, the capacity
curves of these ISI channels are shown.
Polysulphone dosimeters have been employed to measure the erythemally effective UV exposure to the vertex, nose, cheek, chin and side facial sites of 45 volunteer high school students from Hervey Bay, Australia (25.3oS 152.9oE). The results of a series of 1 hour outdoor sport trials (basketball and soccer) found the mean student facial exposure, determined as the arithmetic average of facial site exposures of unprotected students (no hat) to protected students (hat) varied from 140 82 Jm-2 (1σ), to 99 33 Jm-2 (1σ) respectively. All hourly student facial exposures recorded over the study period were found to exceed the National Health and Medical Research Council’s adopted safe daily limit of 30 Jm-2. Facial exposure relative to the received ambient UV increased to the nose at higher (winter) Solar Zenith Angles (SZA) compared with low...
[Abstract]: This paper compares the thermal analysis of three types of random glass fibre reinforced thermoplastic matrix composites joined by adhesives using microwave energy. Fixed frequency, 2.45 GHz, microwave facility is used to join thirty three percent by weight random glass fibre reinforced nylon 66 {Nylon 66/GF (33%0}, thirty three percent by weight random glass fibre reinforced low density polyethylene composite [LDPE/GF (33%0)] and. thirty three percent by weight random glass fibre reinforced polystyrene composite [PS/GF (33%)]. The facility used is shown in Figure 1. With a given power level, the composites were exposed to various exposure times to microwave irradiation. The primer or coupling agent used was 5-minute two-part adhesive. The heat distribution of the samples of the three types of composites was analysed and co...
The current study investigated the coupling of groundwater and surface water nitrogen (N) dynamics over 3 years, and considered intensive agricultural land-management influences over this period where the risk of N loss to water was considered high. Groundwater N (as nitrate) was monitored monthly in different strata and zones in four hillslopes, two in each of two agricultural catchments of c. 10 km2, and stream water N flux was monitored sub-hourly in the catchment outlets. Field nutrient sources were connected to surface water via groundwater; the groundwater along hillslopes was seen to be influenced spatially and temporally by management, geology and weather as observed in the concentration variability of nitrate in groundwater. Based on spatio-temporal averages of nitrate-N concentration, groundwater status was considered good (a...
[Abstract]: Spatial variability in crop production occurs as a result of spatial and temporal variations in soil
structure and fertility; soil physical, chemical and hydraulic properties; irrigation applications; pests
and diseases; and plant genetics. It is argued that this variability can be managed and the efficiency
of irrigation water use increased by spatially variable application of irrigation water to meet the specific needs of individual management zones (areas of crop whose properties are relatively homogenous). The prospects for spatially varied irrigation applications and the need for adaptive control of irrigation application systems are identified. Current work at USQ directed toward adaptive control of furrow irrigation and centre pivot and lateral move machines is described.
[Abstract]: No matter how many and how comprehensive the services a network can provide, in order to satisfy the diverse requirement of services, networks should share services among themselves. For secure service sharing on IP networks, the authenticity of users and the scalability of participating networks are always two major issues among others. Service Network Graph (SNG) was proposed to address the problems of cross network authentication and scalability, which usually occur in a dynamic aggregations of heterogeneous networks.
Our SNG approach is based on Authentication Propagation and Service Paths. Authentication Propagation is a process of relaying authentication results from the authenticating network to the service providing network. Within an SNG, networks delegate authentication duties to some other networks which gathe...
[Abstract]: The influence of WorkChoices legislation has been felt across a broad spectrum of people in society. Women, young people and families are some of the sections of society which have suffered significantly because of this legislation. All this despite the Howard Government assurance that they would not create a system of industrial relations that would cut the wages of Australian workers. What has emerged in the aftermath of the introduction of WorkChoices is that Australia is following the lead of the US and its deregulated industrial relations model. Evidence of this concerning trend has been revealed as stories have begun to emerge in the Australian community, regarding the effects of WorkChoices on women, families and young people. These groups have experienced worsening pay and conditions solely because the of the W...
Technological advances in the area of spatial sciences over the past 10 -- 20 years have
brought about many new equipment types for the capture of 3-dimensional data. An
emerging technology is the terrestrial laser scanner, which enables the collection of detailed
3-D data of an area.
The implementation of the terrestrial laser scanner in the surveying industry has been
slowed by a lack of knowledge of its useful application in comparison with wellunderstood,
and practiced, traditional methods. This leads to the question of whether the
terrestrial laser scanners relative accuracies and its practical use in the field are of value to
the surveying industry.
Scanners allow the collection of data without having to physically touch objects. Their use
as surveying instruments is exceptional in situations of limited access to structures or ta...
The term evaluation applied to engineering education has several connotations. Evaluation occurs at multiple levels. At the course level academics routinely evaluate 'technical' learning outcomes. These courses in turn routinely need to meet evaluation criteria set by individual institutions, such as graduate attributes, grade distributions, minimum load, student satisfaction, cohort progression and attrition. Further, at the program level, coordinators may be concerned with evaluation of total student load, overall progression and attrition, retention startegies, employer surveys, and various quality indices. The capstone is the evaluation carried out by Engineers Australia, which is (partially) based on satisfying the graduate competency requirements of the Washington Accord (as interpreted and applied by Engineers Australia). This p...
Grazing is a major land use in Australia's rangelands. The 'safe' livestock carrying capacity (LCC) required to maintain resource condition is strongly dependent on climate. We reviewed: the approaches for quantifying LCC; current trends in climate and their effect on components of the grazing system; implications of the 'best estimates' of climate change projections for LCC; the agreement and disagreement between the current trends and projections; and the adequacy of current models of forage production in simulating the impact of climate change. We report the results of a sensitivity study of climate change impacts on forage production across the rangelands, and we discuss the more general issues facing grazing enterprises associated with climate change, such as 'known uncertainties' and adaptation responses (e.g. use of climate risk...
