521 resultados para Viikki Tropical Resources Institute
Resumo:
The Sudbury Basin is a non-cylindrical fold basin occupying the central portion of the Sudbury Impact Structure. The impact structure lends itself excellently to explore the structural evolution of continental crust containing a circular region of long-term weakness. In a series of scaled analogue experiments various model crustal configurations were shortened horizontally at a constant rate. In mechanically weakened crust, model basins formed that mimic several first-order structural characteristics of the Sudbury Basin: (1) asymmetric, non-cylindrical folding of the Basin, (2) structures indicating concentric shortening around lateral basin termini and (3) the presence of a zone of strain concentration near the hinge zones of model basins. Geometrically and kinematically this zone corresponds to the South Range Shear Zone of the Sudbury Basin. According to our experiments, this shear zone is a direct mechanical consequence of basin formation, rather than the result of thrusting following folding. Overall, the models highlight the structurally anomalous character of the Sudbury Basin within the Paleoproterozoic Eastern Penokean Orogen. In particular, our models suggest that the Basin formed by pure shear thickening of crust, whereas transpressive deformation prevailed elsewhere in the orogen. The model basin is deformed by thickening and non-cylindrical synformal buckling, while conjugate transpressive shear zones propagated away from its lateral tips. This is consistent with pure shear deformation of a weak circular inclusion in a strong matrix. The models suggest that the Sudbury Basin formed as a consequence of long-term weakening of the upper crust by meteorite impact.
Resumo:
The cause of upper-crustal segmentation into rhomb-shaped, shear zone-bound domains associated with contractional sedimentary basins in hot, wide orogens is not well understood. Here we use scaled multilayered analogue experiments to investigate the role of an orogen-parallel crustal-strength gradient on the formation of such structures. We show that the aspect ratio and size of domains, the sinuous character and abundance of transpressional shear zones vary with the integrated mechanical strength of crust. Upper-crustal deformation patterns and the degree of strain localization in the experiments are controlled by the ratio between the brittle and ductile strength in the model crust as well as gradients in tectonic and buoyancy forces. The experimental results match the first-order kinematic and structural characteristics of the southern Central Andes and provide insight on the dynamics of underlying deformation patterns in hot, wide orogens.
Resumo:
The geometry of ductile strain localization phenomena is related to the rheology of the deformed rocks. Both qualitative and quantitative rheological properties of natural rocks have been estimated from finite field structures such as folds and shear zones. We apply physical modelling to investigate the relationship between rheology and the temporal evolution of the width and transversal strain distribution in shear zones, both of which have been used previously as rheological proxies. Geologically relevant materials with well-characterized rheological properties (Newtonian, strain hardening, strain softening, Mohr-Coulomb) are deformed in a shear box and observed with Particle Imaging Velocimetry (PIV). It is shown that the width and strain distribution histories in model shear zones display characteristic finite responses related to material properties as predicted by previous studies. Application of the results to natural shear zones in the field is discussed. An investigation of the impact of 3D boundary conditions in the experiments demonstrates that quantitative methods for estimating rheology from finite natural structures must take these into account carefully.
Resumo:
Recent advancements in the capabilities of information and communication technologies (ICT) offer unique avenues to support the delivery of nutrition care. Despite ICTs being widely available, evidence on the practices and attitudes with regard to ICT use among dietitians is limited. A cross-sectional survey of Dietitians Association of Australia members was administered online in August 2011. All dietitians who responded (n=87) had access to a computer at work. Half reported providing non face-to-face consultations, with the telephone and email the most common modes of delivery. The use of smart phones was prevalent for 49% of practitioners, with 30% recommending nutrition-related applications and/or programs to clients. Benefits to technology use in practice most commonly reported included improvements in access to information/resources, time management, and workflow efficiency. Barriers identified related to cost and access to technology, and lack of suitable programs/applications. Technology was viewed as an important tool in practice among 93% of dietitians surveyed, however only 38% were satisfied with their current level of use. The majority (81%) believed more technology should be integrated within dietetics, while 85% indicated that the development of suitable and practical applications andprograms is necessary for future practice. Technology is regarded as an important tool by Australian dietitians, with an expressed need for theirinclusion to further facilitate nutrition care. Regular and ongoing evaluation of technology use among dietitians is vital to ensure thatapplications and use are evidence based and relevant to consumers in the digital world.
Resumo:
Photographic records of dietary intake (PhDRs) are an innovative method for the dietary assessment and may alleviate the burden of recording intake compared to traditional methods of recording intake. While the performance of PhDRs has been evaluated, no investigation into the application of this method had occurre within dietetic practice. This study examined the attitudes of dietitians towards the use of PhDRs in the provision of nutrition care. A web-based survey on the practices and beliefs with regards to technology use among Dietitians Association of Australia members was conducted in August 2011. Of the 87 dietitians who responded, 86% assessed the intakes of clients as part of individualised medical nutrition therapy, with the diet history the most common method used. The majority (91%) of dietitians surveyed believed that a PhDR would be of use in their current practice to estimate intake. Information contained in the PhDR would primarily be used to obtain a qualitative evaluation of diet (84%) or to supplement an existing assessment method (69%), as opposed to deriving an absolute measure of nutrient intake (31%). Most (87%) indicated that a PhDR would also be beneficial in both the delivery of the intervention and to evaluate and monitor goals and outcomes, while only 46% felt that a PhDR would assist in determining the nutrition diagnosis. This survey highlights the potential for the use of PhDRs within practice. Future endeavours lie in establishing resources which support the inclusion of PhDRs within the nutrition care process.
Resumo:
Control Objectives for Information and related Technology (COBIT) has grown to be one of the most significant IT Governance (ITG) frameworks available and also the best suited for audit, as it provides comprehensive guidance around IT processes and related business goals. However, given the constraints of both time and resources within which the Australian public sector is forced to operate, implementing an audit framework the size of COBIT in its entirety is often considered too large a task. As an alternative to full implementation it is not uncommon for the public sector to “cherry pick” controls from the framework in an effort to reduce its size. This paper reports on research undertaken to evaluate the potential to use an optimised sub-set of COBIT 5 for ITG audit in Australian public sector organisations. A survey methodology was employed to determine the control-objectives considered to be the most important to a selection of public sector organisations. Twelve control-objectives were identified as being most important to Queensland public sector organisations. As ten of these were also identified by previous studies, it appears possible to derive an optimised sub-set from COBIT 5 that would be both enduring and relevant across geographical and organisational contexts.
Resumo:
The suitability of Role Based Access Control (RBAC) is being challenged in dynamic environments like healthcare. In an RBAC system, a user's legitimate access may be denied if their need has not been anticipated by the security administrator at the time of policy specification. Alternatively, even when the policy is correctly specified an authorised user may accidentally or intentionally misuse the granted permission. The heart of the challenge is the intrinsic unpredictability of users' operational needs as well as their incentives to misuse permissions. In this paper we propose a novel Budget-aware Role Based Access Control (B-RBAC) model that extends RBAC with the explicit notion of budget and cost, where users are assigned a limited budget through which they pay for the cost of permissions they need. We propose a model where the value of resources are explicitly defined and an RBAC policy is used as a reference point to discriminate the price of access permissions, as opposed to representing hard and fast rules for making access decisions. This approach has several desirable properties. It enables users to acquire unassigned permissions if they deem them necessary. However, users misuse capability is always bounded by their allocated budget and is further adjustable through the discrimination of permission prices. Finally, it provides a uniform mechanism for the detection and prevention of misuses.
Resumo:
This paper proposes a technique that supports process participants in making risk-informed decisions, with the aim to reduce the process risks. Risk reduction involves decreasing the likelihood and severity of a process fault from occurring. Given a process exposed to risks, e.g. a financial process exposed to a risk of reputation loss, we enact this process and whenever a process participant needs to provide input to the process, e.g. by selecting the next task to execute or by filling out a form, we prompt the participant with the expected risk that a given fault will occur given the particular input. These risks are predicted by traversing decision trees generated from the logs of past process executions and considering process data, involved resources, task durations and contextual information like task frequencies. The approach has been implemented in the YAWL system and its effectiveness evaluated. The results show that the process instances executed in the tests complete with substantially fewer faults and with lower fault severities, when taking into account the recommendations provided by our technique.
Resumo:
Acid sulfate soils (ASS) are one of the stressor factors that cause many mangrove restoration projects to fail. Achieving successful rehabilitation in an ASS affected area requires an understanding of the geochemical conditions that influence the establishment and growth of mangrove seedlings. This study evaluated the effect of tidal inundation on geochemical conditions on sub layer to better understand their impacts on the density, establishment, and growth of mangrove seedlings. This study also examined the geochemical conditions under which mangrove seedlings can establish naturally, and/or be replanted in abandoned aquaculture ponds. The study area was in an area of abandoned aquaculture ponds situated in the Mare District, adjacent to Bone Bay, South Sulawesi, Indonesia.The pH, pHfox, redox potential, organic content, water soluble sulfate, SKCl, SPOS, and grain size of the soil from the sediment core at + 10 - 15 cm depth near roots were measured using. Pyrite analysis were conducted for the top and sub sediments. The density, establishment, and the relative root growth of Rhizophoraceae were also determined. Free tidal inundation at abandoned pond sites improved the sediment quality. The high density, establishment, and growth of mangrove seedlings were characterized by freely drained areas with a higher pH (field and oxidisable), lower organic content, and high proportion of silt/clay. Higher density and growth also correlated to reduced environments. Sulfur species did not influence the density, establishment, and growth of the seedlings directly. The supply of propagules from the mangrove stands, or access from good waterways were also important for seedlings to establish naturally.
Resumo:
As features of the landscape, waterfalls have been studied extensively by geographers, but the names given to these landforms have received relatively little scholarly attention. This paper examines the naming of waterfalls and addresses the question of classifying these hydronyms. The subject is considered in a global historical context, focusing on place names in the anglophone world. Until the 18th and 19th centuries, relatively few waterfalls were named.With the beginning of the Industrial Revolution, water power rose in economic importance, and at the same time, there was a growing scientific and aesthetic engagement with the landscape. These developments are suggested as reasons for the increased interest in waterfalls which were then being recorded in topographical literature and on maps, individual names being given to increasing numbers of falls. European exploration added to the knowledge of the world’s waterfalls, many of which were given names by their ‘discoverers’. This naming process accelerated with the growth of domestic and overseas tourism which exploited scenic resources such as waterfalls. Until now, research on the names of waterfalls has been fragmentary, and the classification of these hydronyms has been neglected. This paper demonstrates that waterfall names can be classified in accordance with a recognised toponymic typology. Using examples drawn from waterfall guidebooks, databases, maps, and other sources, the following discussion supports George Stewart’s claim that his toponymic classification is valid for place names of all kinds.
Resumo:
A telephone survey was conducted to describe current practices and policies of patient transport in Australian hospitals.The survey had a 94% response rate. Results showed considerable variability and ambiguity throughout the samplein both practice and policy. Findings also indicated that criteria used for transport practices were predominantlyshaped by physiological and technological considerations. Factors related to human and financial resources, as well aspsychological and emotional aspects of the patient's condition, received little attention.