93 resultados para pacs: security aspects of it

em Deakin Research Online - Australia


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IT Security Certification is an increasingly important qualification for information technology (IT) professionals seeking employment in IT security. Yet currently there is a lack of rigorously developed approaches to support the evaluation and selection by key stakeholders of the most appropriate IT security certification scheme from among hundreds of vendor-neutral and vendor-specific schemes. This paper develops a framework based on categories, characteristics and criteria to support user evaluation and selection of an (IT) Security Certification scheme that satisfies user priorities and requirements. The paper illustrates the use of the framework to support an experienced IT Professional’s evaluation. Theoretical and practical implications of the framework and trial evaluation are discussed.

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The natriuretic peptide system is a complex family of peptides and receptors that is primarily linked to the maintenance of osmotic and cardiovascular homeostasis. A natriuretic peptide system is present in each vertebrate class but there are varying degrees of complexity in the system. In agnathans and chondrichthyians, only one natriuretic peptide has been identified, while new data has revealed that multiple types of natriuretic peptides are present in bony fish. However, it seems in tetrapods that there has been a reduction in the number of natriuretic peptide genes, such that only three natriuretic peptides are present in mammals. The peptides act via a family of guanylyl cyclase receptors to generate the second messenger cGMP, which  mediates a range of physiological effects at key targets such as the gills, kidney and the cardiovascular system. This review summarises the current knowledge of the natriuretic peptide system in non-mammalian vertebrates and discusses the physiological actions of the peptides.

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This paper reports results from surveys of community organisation members, workers and volunteers designed to measure aspects of active citizenship in four locations: Ballarat (Australia); Norwich and Downham Market (England), and Mitischi (Russia). These data are drawn from an ongoing comparative study that will include six countries in the final analysis. The aggregated data considered here lend support to propositions that tolerance is positively associated with both civic participation and trust but do not show evidence for association between civic participation and trust. However, the existence of considerable locality level variation underlines the importance of taking context into account when assessing the role and nature of civic participation. Across the four locations, two broad patterns of (relative) active citizenship are described by means of a typology of active citizens. Predictors of tolerance and civic participation are identified through standard multiple regressions. It is concluded that future research needs to uncover the explanatory factors that lie behind these representations and which could further specify not just the similarities but also the differences between the locations.

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It is conventional wisdom that contextualising mathematics tasks can make them more meaningful for students, and that open-ended questions create opportunities for student engagement. Yet concerns are emerging that strategies such as these may exacerbate the disadvantage of some. We report data from a project that seeks to address such concerns by encouraging teachers to be explicit about aspects of their pedagogy. Men teachers were explicit about aspects of the pedagogy, the students responded in the direction intended.

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Lactobacillus plantarum and subspecies of Lactobacillus casei were isolated from good quality mature Cheddar cheese and characterized with respect to metabolic functions that would allow their use in cheesemaking. In this way microbiological control of the maturation process with particular emphasis on protein catabolism was achieved. The lactobacilli isolated were selected for low growth rates (and acid production) in milk, and low proteinase activity to allow for their addition in high numbers to cheesemilk together with the normal starter flora (group N streptococci). The growth and acid production of the starter bacteria were unaffected by the presence of the lactobacilli during cheese manufacture and it was found that the added lactobacilli were able to grow and function under the conditions prevalent in Cheddar cheese during maturation. It was also demonstrated that the lactobacilli could be grown in an artificial medium to high numbers under controlled conditions and could be harvested for the preparation of cell concentrates, a necessary characteristic for commercialization. The lactobacilli also metabolized citrate, a potential problem in cheese maturation associated with C02 production but this did not adversely affect the maturation process under the conditions used. Compared to the group N streptococci the non-starter lactobacilli possessed a proteinase system that had a higher temperature optimum and was less affected by heat and sodium chloride. They also possessed a more active peptidase system although both the lactobacilli and the starter organisms possessed a similar range of peptidases. Non-starter lactobacilli were added to normal cheese and cheese made with proteinase negative starter. The added organisms did not adversely affect manufacturing parameters and did not metabolize citrate or lead to the formation of biogenic amines. However protein catabolism rates, particularly with respect to peptide degradation, were increased, as was flavour development and intensity. It was observed that the body and texture of the cheeses was unaffected by the treatment. By controlling both the starter and non-starter microflora in the cheeses a practical system for favourably influencing cheese maturation was possible. The investigation has demonstrated that carefully selected and characterized non-starter lactobacilli can be incorporated into Cheddar cheese manufacture in order to influence flavour development during maturation. Moreover the organisms can be added to the vat stage of manufacture without causing problems to the manufacturing process. This approach is a simple cost effective means of improving the cost of Cheddar cheese production and provides an unique opportunity to improve and control quality of all Cheddar cheese produced.

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In the last 30 to 40 years, many researchers have combined to build the knowledge base of theory and solution techniques that can be applied to the case of differential equations which include the effects of noise. This class of ``noisy'' differential equations is now known as stochastic differential equations (SDEs). Markov diffusion processes are included within the field of SDEs through the drift and diffusion components of the Itô form of an SDE. When these drift and diffusion components are moderately smooth functions, then the processes' transition probability densities satisfy the Fokker-Planck-Kolmogorov (FPK) equation -- an ordinary partial differential equation (PDE). Thus there is a mathematical inter-relationship that allows solutions of SDEs to be determined from the solution of a noise free differential equation which has been extensively studied since the 1920s. The main numerical solution technique employed to solve the FPK equation is the classical Finite Element Method (FEM). The FEM is of particular importance to engineers when used to solve FPK systems that describe noisy oscillators. The FEM is a powerful tool but is limited in that it is cumbersome when applied to multidimensional systems and can lead to large and complex matrix systems with their inherent solution and storage problems. I show in this thesis that the stochastic Taylor series (TS) based time discretisation approach to the solution of SDEs is an efficient and accurate technique that provides transition and steady state solutions to the associated FPK equation. The TS approach to the solution of SDEs has certain advantages over the classical techniques. These advantages include their ability to effectively tackle stiff systems, their simplicity of derivation and their ease of implementation and re-use. Unlike the FEM approach, which is difficult to apply in even only two dimensions, the simplicity of the TS approach is independant of the dimension of the system under investigation. Their main disadvantage, that of requiring a large number of simulations and the associated CPU requirements, is countered by their underlying structure which makes them perfectly suited for use on the now prevalent parallel or distributed processing systems. In summary, l will compare the TS solution of SDEs to the solution of the associated FPK equations using the classical FEM technique. One, two and three dimensional FPK systems that describe noisy oscillators have been chosen for the analysis. As higher dimensional FPK systems are rarely mentioned in the literature, the TS approach will be extended to essentially infinite dimensional systems through the solution of stochastic PDEs. In making these comparisons, the advantages of modern computing tools such as computer algebra systems and simulation software, when used as an adjunct to the solution of SDEs or their associated FPK equations, are demonstrated.

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Diseases in natural ecosystems are often assumed to be less severe than those observed in domestic cropping systems due to the extensive biodiversity exhibited in wild vegetation communities. In Australia, it is this natural biodiversity that is now under threat from Phytophthora cinnamomi. The soilborne Oomycete causes severe decline of native vegetation communities in south-western Victoria, Australia, disrupting the ecological balance of native forest and heathland communities. While the effect of disease caused by P. cinnamomi on native vegetation communities in Victoria has been extensively investigated, little work has focused on the Anglesea healthlands in south-western Victoria. Nothing is known about the population structure of P. cinnamomi at Anglesea. This project was divided into two main components to investigate fundamental issues affecting the management of P. cinnamomi in the Anglesea heathlands. The first component examined the phenotypic characteristics of P. cinnamomi isolates sampled from the population at Anglesea, and compared these with isolates from other regions in Victoria, and also from Western Australia. The second component of the project investigated the effect of the fungicide phosphonate on the host response following infection by P. cinnamomi. Following soil sampling in the Anglesea heathlands, a collection of P, cinnamomi isolates was established. Morphological and physiological traits of each isolate were examined. All isolates were found to be of the A2 mating type. Variation was demonstrated among isolates in the following characteristics: radial growth rate on various nutrient media, sporangial production, and sporangial dimensions. Oogonial dimensions did not differ significantly between isolates. Morphological and physiological variation was rarely dependant on isolate origin. To examine the genetic diversity among isolates and to determine whether phenotypic variation observed was genetically based, Random Amplified Polymorphic DNA (RAPD) analyses were conducted. No significant variation was observed among isolates based on an analysis of molecular variance (AMQVA). The results are discussed in relation to population biology, and the effect of genetic variation on population structure and population dynamics. X australis, an arborescent monocotyledon indigenous to Australia, is highly susceptible to infection by P. cinnamomi. It forms an important component of the heathland vegetation community, providing habitat for native flora and fauna, A cell suspension culture system was developed to investigate the effect of the fungicide phosphonate on the host-pathogen interaction between X. australis and P. cinnamomi. This allowed the interaction between the host and the pathogen to be examined at a cellular level. Subsequently, histological studies using X. australis seedlings were undertaken to support the cellular study. Observations in the cell culture system correlated well with those in the plant. The anatomical structure of X australis roots was examined to assist in the interpretation of results of histopathological studies. The infection of single cells and roots of X. australis, and the effect of phosphonate on the interaction are described. Phosphonate application prior to inoculation with P. cinnamomi reduced the infection of cells in culture and of cells in planta. In particular, phosphonate was found to stimulate the production of phenolic material in roots of X australis seedlings and in cells in suspension cultures. In phosphonate-treated roots of X australis seedlings, the deposition of electron dense material, possibly lignin or cellulose, was observed following infection with P. cinnamomi. It is proposed that this is a significant consequence of the stimulation of plant defence pathways by the fungicide. Results of the study are discussed in terms of the implications of the findings on management of the Anglesea heathlands in Victoria, taking into account variation in pathogen morphology, pathogenicity and genotype. The mode of action of phosphonate in the plant is discussed in relation to plant physiology and biochemistry.

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The abalone Haliotis laevigata Donovan is commercially exploited in southern Australia; Haliotis scalaris Leach is a smaller, noncommercial species. This thesis describes the early life history of both species and other aspects of the fishery biology of H. Iaevigata required for fishery management. Both abalone species recruit onto a crustose coralline substratum variously from spring to winter. After settlement the growth rate of both species Is linear for a number of years (1 .7mm/month for H. Iaevigata and 1.1mm/month for H. scalaris) . Crustose coralline algae are the main food during the first year of life but thereafter the diet switches largely to drift algae and seagrass. Survival of newly-settled cohorts differed between years and between species. Overall, it appeared to be density Independent at low densities but density-dependent at high densities, Recruitment strength (measured at 2-1/2 - 3 years of age) and natural mortality of adults in a closed population was measured over 17 years at West I. There were sequences of strong and weak recruitments, but no relationship with presumed spawning stock size was apparent. Adult natural mortality rates ranged from 0.02 to 0.86 and were strongly density dependent. Stingrays were a major, and octopuses a minor, cause of mortality. The fecundity of H. Iaevigata was investigated at a number of sites and was adequately described by linear regressions of fecundity on total weight. Fecundity ratios and growth rate differed between sites and fecundity appears subject to phenotyplc and genotypic variation. The short and long term movement of H. laevigata was also examined, !n short term studies sexually mature Individuals aggregate during the spawning season but disperse randomly at other times of the year. In the longer term the amount of movement depends on availability of crevice space and size. Movement is also directional and, at one site, was toward that of the approaching swell. A method is described for estimating density of abalone by using a free-range search technique and adjusting for individual variation in power and efficiency of different divers and in differing degrees of habitat heterogeneity. The method is useful for estimating recruitment strength and density of abalone in surveys of abalone stocks.

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The age and growth, reproduction and diet of several skate species in south-east Australia were studied. From studying these life history characteristics it was determined that skates have a relatively low productivity and may therefore be at risk of local extinction if increasingly exploited without appropriate management.

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This study investigated the nest site selection characteristics and diet of the Wedge-tailed Eagle, Aquila audax, in southern Victoria. It was found that sites where local topography afforded some protection from adverse weather and where the nest tree was live were most commonly selected. Rabbits were found to the major prey item of this eagle.

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A practical teaching difficulty arising in a conducive environment provided opportunity to turn the particular problem into a case study with generic implications. Little research has been conducted on the use or effectiveness of simulation games for teaching entrepreneurship. In the context of established literature critiquing the effectiveness of simulation games as teaching devices in managerial contexts and at a point where problems in using a simulation game as part of entrepreneurship course became evident, the authors designed and executed a single-case research project to generate initial theoretical propositions about the pedagogical effectiveness of simulation games for teaching various concepts and aspects of entrepreneurship. The case analysed the perceived learning environment created when the Sky-High simulation was played by 41 MBA students taking an elective entrepreneurship course at INSEAD. The research design embodied the established methodological principles specified by Yin (1989), for effective case research. Theory building was based upon the grounded-theorizing procedures articulated by Glaser and Strauss (1967). Analysis and synthesis produced a grounded theory, in the form of a normative argument, containing four attribute categories and associated properties required of a simulation game to make it an efficacious teaching device in entrepreneurship contexts. The establishment of this grounded theory has made it both desirable and feasible to contemplate creation of an ISO quality standard for educational simulation games.

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The protection of critical irifrastructures and the choices made in terms of priorities and cost, all impact upon the planning, precautions and security aspects of protecting these important systems. Often the when choices made is difficult to assess at the time the decision is taken and it is only after an incident that the truth of the choices made become fit!ly evident. The paper focllses on two recent examples of Australian Critical Infrastructure protection and the issues that related to those examples.