Electromagnetic receiving properties of overhead power line

This paper examines the use of overhead power transmission lines as electromagnetic sensors for detecting electric discharges caused by defective power transmission equipment. The experimental study involved the use of a spark gap (point-point configuration) and two HV conductors of different lengths to simulate electric discharge that takes place on transmission line. The experimental results show that large amount of energy are coupled onto the conductors and the amount of electromagnetic energy is dependent on the length of the conductor and the distance between the source and the conductor.

Management of power line easement vegetation for small mammal conservation in Australia : a case study of the broad-toothed rat (Mastacomys fuscus)

Within Australia, very little attention has been given to the potential biodiversity benefits of power line easements, if ecologically sensitive management regimes are developed. This study examined the potential power line easements may have for the conservation of small mammals, and in particular the near threatened, Broad-toothed Rat Mastacomys fuscus, in Australia. Easement vegetation was found to support a diverse small mammal community, including M. fuscus if the vegetation was allowed to develop some structural complexity. M. fuscus was one of the first species to recolonize the easement habitat, provided that the areas had regenerated to a sufficient level. Results suggests; however, that the current management technique used, where the entire easement is managed at one time via mass slashing, on short rotation times, is most likely limiting M. fuscus to low abundances, and causing isolation of the current M. fuscus populations. To ensure that power line easements supply functional, usable habitat for small mammals and other species and to minimize their potential to fragment small mammal populations, it is recommended that current management techniques be reassessed. In an effort to develop more appropriate management regimes, it was recommended that rotation times be increased between management, that mass slashing of the easement at one time be reassessed, especially in naturally low growing areas and that rotational type slashing be implemented. Other techniques such as spot spraying, may be all that is needed within some areas to control emergent saplings. This study highlights that potential biodiversity values do exist for Australian power line easements, if some changes occur to the current management practices.

A video-based real-time vehicle detection method by classified background learning

A new two-level real-time vehicle detection method is proposed in order to meet the robustness and efficiency requirements of real world applications. At the high level, pixels of the background image are classified into three categories according to the characteristics of Red, Green, Blue (RGB) curves. The robustness of the classification is further enhanced by using
line detection and pattern connectivity. At the lower level, an exponential forgetting algorithm with adaptive parameters for different categories is utilised to calculate the background and reduce the distortion by the small motion of video cameras. Scene tests show that the proposed method is more robust and faster than previous methods, which is very suitable for real-time vehicle detection in outdoor environments, especially concerning locations where the level of illumination changes frequently and speed detection is important.

The power of play-break for automatic detection and browsing of self-consumable sport video highlights

To enable content-based retrieval, highlights extraction from broadcasted sport video has been an active research topic in the last decade. There is a well-known theory that high-level semantic, such as goal in soccer can be detected based on the occurrences of specific audio and visual features that can be extracted automatically. However, there is yet a definitive solution for the scope (i.e. start and end) of the detection for self consumable highlights. Thus, in this paper we will primarily demonstrate the benefits of using play-break for this purpose. Moreover, we also propose a browsing scheme that is based on integrated play-break and highlights (extended from [1]). To validate our approach, we will present the results from some experiments and a user study.

Application of an adaptive neural network with symbolic rule extraction to fault detection and diagnosis in a power generation plant

Artificial neural networks have a good potential to be employed for fault diagnosis and condition monitoring problems in complex processes. In this paper, the applicability of the fuzzy ARTMAP (FAM) neural network as an intelligent learning system for fault detection and diagnosis in a power generation plant is described. The process under scrutiny is the circulating water (CW) system, with specific attention to the conditions of heat transfer and tube blockage in the CW system. A series of experiments has been conducted systematically to investigate the effectiveness of FAM in fault detection and diagnosis tasks. In addition, a set of domain rules has been extracted from the trained FAM network so that its predictions can be explained and justified. The outcomes demonstrate the benefits of employing FAM as an intelligent fault detection and diagnosis tool with an explanatory capability for monitoring and diagnosing complex processes in power generation plants.

Language and power in vocational education and training

In this paper I explore the way language is used in Training Packages, and the impact this language has when Training Packages are used to support work-based vocational programs. Training Packages are a fundamental component of the regulatory framework of the national vocational education and training (VET) system [in Australia]. The national strategy for VET places employers and individuals at the centre of VET, and policy commitments to access and equity are enshrined in the auditable standards of the Australian Quality Training Framework (AQTF). Yet Training Packages and related official VET texts are written in an abstract, generalised and complex language form which acts as an insurmountable barrier to many people at the front line of VET. My PhD research (a work in progress) explores the proposition that this language form is representative of, and constructive in, unequal power relationships. Early data analysis suggests that VET practitioners and training participants talk about their experience of this language in terms of power and exclusion. In contrast, the official VET response generally leaves the official language form above challenge, and instead largely focuses on the presumed deficient language and literacy skills of those who are excluded by these texts.

The effects of time pressure and experience on nurses' risk assessment decisions : a signal detection analysis

Background: Time pressure and, occasionally, suboptimal assessment decisions are features of nursing in acute care.

Objectives: To explore the effect of generic and specialist clinical experience on the ability to detect the need to take action in acute care and the impact of time pressure on nurses' decision-making performance.

Methods: Experienced acute care registered nurses (n = 241) were presented with 50 vignettes of real clinical risk assessments. Each vignette contained seven information cues. In response to these vignettes, nurses had to decide whether to intervene or not. The 26 vignettes were time limited and mixed randomly into the 50 cases. Signal detection analysis was used to establish nurses' performance, personal decision thresholds ([beta]), and their abilities (d') to distinguish a signal of clinical risk from the clinical noise of noncontributory information.

Results: Nurses had significantly lower d' and were significantly less likely to indicate intervening under time pressure. For ability-but not threshold-there was a significant interaction of time pressure and years of experience in acute care. With no time pressure, d' increased in line with years of experience. Under time pressure, there was no effect.

Discussion: Time pressure reduced nurses' ability to detect the need and the tendency to report intervening. Thus, there were more failures to report appropriate intervention under time pressure, and the positive effects of clinical experience were negated under time pressure. More and larger scale research on the effect on clinical outcomes of time pressured nursing choices is required.

The analysis of café espresso using two-dimensional reversed phase–reversed phase high performance liquid chromatography with UV-absorbance and chemiluminescence detection

In this study, an activity based screening technique combining two-dimensional liquid chromatography (2DHPLC) with UV-absorbance and chemiluminescence detection was applied to study “Ristretto”, "Decaffeinatto” and “Volluto” espresso coffees. This technique, which coupled the separation power of 2DHPLC with the sensitivity and selectivity of the chemiluminescence detection, offers great potential for screening complex samples for antioxidant compounds. Detailed information regarding the complexity of the sample, and the variation between these three coffees could be obtained using this multidimensional-hyphenated method of analysis.

High performance liquid chromatography with two simultaneous on-line antioxidant assays : evaluation and comparison of espresso coffees

The antioxidant profiles of various espresso coffees were established using HPLC with UV-absorbance detection and two rapid, simultaneous, on-line chemical assays that enabled the relative reactivity of sample components to be screened. The assays were based on (i) the colour change associated with reduction of the 2,2´-diphenyl-1-picrylhydrazyl radical (DPPH•); and (ii) the emission of light (chemiluminescence) upon reaction with acidic potassium permanganate. Results from the two approaches were similar and reflected the complex array of antioxidant species present in the samples. However, some differences in selectivity were observed. Chromatograms generated with the chemiluminescence assay contained more peaks, which was ascribed to the greater sensitivity of the reagent towards minor, readily oxidisable sample components. The three coffee samples produced closely related profiles, signifying their fundamentally similar chemical compositions and origin. Nevertheless, the overall intensity and complexity of the samples in both UV absorption and antioxidant assay chromatograms were aligned with the manufacturers description of flavour intensity and character.

Conjugated polymer−titania nanoparticle hybrid films : random lasing action and ultrasensitive detection of explosive vapors

We have first demonstrated that a random laser action generated by a hybrid film composed of a semiconducting organic polymer (SOP) and TiO₂ nanoparticles can be used to detect 2,4,6-trinitrotoluene (TNT) vapors. The hybrid film was fabricated by spin-casting SOP solution dispersed with nanosized TiO₂ particles on quartz glass. The SOP in the hybrid film functioned as both the gain medium and the sensory transducer. A random lasing action was observed with a certain pump power when the size (diameter of 50 nm) and concentration (8.9 - 10¹²/cm³) of TiO₂ nanoparticles were optimized. Measurements of fluorescence quenching behavior of the hybrid film in TNT vapor atmosphere (10 ppb) showed that attenuated lasing in optically pumped hybrid film displayed a sensitivity to vapors of explosives more than 20 times higher than was observed from spontaneous emission. This phenomenon has been explained with the four-level laser model. Since the sensory transducer used in the hybrid polymer/nanoparticles system could be replaced by other functional materials, the concept developed could be extended to more general domains of chemical or environment detection.

Edge detection is a projection

A desirable property of any edge detector is that it be a projection in the mathematical sense, that is, that when it is applied to its own output it produces no further change. This report examines the behaviour of some conventional and some new operators when applied to line-drawings. The Marr-Hildreth and some gradient operators are among the conventional operators examined. Also a class of energy feature detectors is explored. It is shown that the energy feature detector is a true projection and does not proliferate edges when applied to a line-drawing, whereas several of the conventional operators do.