996 resultados para Coordinate subtangent


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Terrorist groups are currently using information and communication technologies (ICTs) to orchestrate their conventional attacks. More recently, terrorists have been developing a new form of capability within the cyber-arena to coordinate cyber-based attacks. This chapter identifies that cyber-terrorism capabilities are an integral, imperative, yet under-researched component in establishing, and enhancing cyber-terrorism risk assessment models for SCADA systems. This chapter examines a cyber-terrorism SCADA risk framework that has been adopted and validated by SCADA industry practitioners. The chapter proposes a high level managerial framework, which is designed to measure and protect SCADA systems from the threat of cyber-terrorism within Australia. The findings and results of an industry focus group are presented in support of the developed framework for SCADA industry acceptance.

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Grid transaction management aims at guaranteeing the system consistency in face of various failures in Grid environments. In this paper, we propose a Grid transaction service (GridTS) and design coordination mechanisms for atomic, long-lived and real-time Grid transactions respectively, based on the features of Grid environments. GridTS has the following three advantages. Firstly, it separates the transaction management unit with transaction coordination algorithms so that it can coordinate the above three categories of transactions in a uniform way. Secondly, GridTS can dynamically generate compensating transactions during the long-lived transaction processing. Finally, it provides the programming interfaces similar to traditional distributed transactions. Moreover, we implement a Grid transaction development kit (GridTDK) for application programmers based on our GridTS. We evaluate the feasibility and effectiveness of GridTS by developing an application system using our GridTDK. ©2012 CRL Publishing Ltd.

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 This paper presents a functional observer scheme using two sliding mode observers in cascade. A coordinate transformation is performed on the system such that existing sliding mode observer theory can be directly applied to achieve functional state estimation. The necessary and sufficient existence conditions for the scheme (in terms of the original system matrices) are also investigated, and they are found to be less stringent than earlier work on functional state estimation using one sliding mode observer; this could have benefits in terms of cost and simplicity. A numerical example verifies the effectiveness of the scheme.

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Sea turtles are known to perform long-distance, oceanic migrations between disparate feeding areas and breeding sites, some of them located on isolated oceanic islands. These migrations demonstrate impressive navigational abilities, but the sensory mechanisms used are still largely unknown. Green turtles breeding at Ascension Island perform long oceanic migrations (>2200 km) between foraging areas along the Brazilian coast and the isolated island. By performing displacement experiments of female green turtles tracked by satellite telemetry in the waters around Ascension Island we investigated which strategies most probably are used by the turtles in locating the island. In the present paper we analysed the search trajectories in relation to alternative navigation strategies including the use of global geomagnetic cues, ocean currents, celestial cues and wind. The results suggest that the turtles did not use chemical information transported with ocean currents. Neither did the results indicate that the turtles use true bi-coordinate geomagnetic navigation nor did they use indirect navigation with respect to any of the available magnetic gradients (total field intensity, horizontal field intensity, vertical field intensity, inclination and declination) or celestial cues. The female green turtles successfully locating Ascension Island seemed to use a combination of searching followed by beaconing, since they searched for sensory contact with the island until they reached positions NW and N of the Island and from there presumably used cues transported by wind to locate the island during the final stages of the search.

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Albatrosses and sea turtles are known to perform extremely long-distance journeys between disparate feeding areas and breeding sites located on small, isolated, oceanic islands or at specific coastal sites. These oceanic journeys, performed mainly over or through apparently featureless mediums, indicate impressive navigational abilities, and the sensory mechanisms used are still largely unknown. This research used three different approaches to investigate whether bi-coordinate navigation based on magnetic field gradients is likely to explain the navigational performance of wandering albatrosses in the South Atlantic and Indian Oceans and of green turtles breeding on Ascension Island in the South Atlantic Ocean. The possibility that magnetic field parameters can potentially be used in a bi-coordinate magnetic map by wandering albatrosses in their foraging area was investigated by analysing satellite telemetry data published in the literature. The possibilities for using bi-coordinate magnetic navigation varied widely between different areas of the Southern Oceans, indicating that a common mechanism, based on a bi-coordinate geomagnetic map alone, was unlikely for navigation in these areas. In the second approach, satellite telemetry was used to investigate whether Ascension Island green turtles use magnetic information for navigation during migration from their breeding island to foraging areas in Brazilian coastal waters. Disturbing magnets were applied to the heads and carapaces of the turtles, but these appeared to have little effect on their ability to navigate. The only possible effect observed was that some of the turtles with magnets attached were heading for foraging areas slightly south of the control turtles along the Brazilian coast. In the third approach, breeding female green turtles were deliberately displaced in the waters around Ascension Island to investigate which cues these turtles might use to locate and return to the island; the results suggested that cues transported by wind might be involved in the final stages of navigation.

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Nest visit synchrony, whereby adults coordinate their visits to the nest, has been documented in several species of cooperative breeders. Visit synchrony may reduce nest predation rate or sibling competition, or instead follow from synchronisation of other behaviours, such as foraging. However, nest visit synchrony has rarely been considered in species with bi-parental care, even though it could conceivably bring similar fitness benefits to that seen in cooperative breeders. In addition, in species with bi-parental care, we might expect nest visit synchrony to reflect the quality of the pair or the overall coordination of breeding activity between partners. Here, we tested whether nest visit synchrony occurs in a classic avian model for the study of bi-parental care, the zebra finch Taeniopygia guttata. We found that in the wild, both zebra finch parents visited the nest very infrequently during nestling provisioning, with only one visit per hour, and that nest visits were highly synchronised with parents visiting the nest together on 78% of the visits. In addition, we found that nest visit synchrony was correlated with hatching rate, brood size at hatching and the number of offspring in the nest a few days prior to fledging. Our results suggest that, while more work is required to understand the benefits of nest visit synchrony in this species, considering behavioural synchrony and cooperation between mated partners may offer new insight into the study of parental investment, including in species with bi-parental care.

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Human associated delay-tolerant networks (HDTNs) are new networks for DTNs, where mobile devices are associated with humans and demonstrate social-related communication characteristics. As most of recent works use the social attributes to study the date forwarding in HDTNs and these attributes are critical for the data provider, how to use the anonymous attributes becomes a serious issue. In this paper, we propose a three-dimensional coordinate model by using the anonymous attributes to perform the data forwarding. We use MIT reality dataset, which is a human associated mobile network trace file, to simulate our model. The results of simulations show that the proposed model can use the anonymous attributes to achieve a high data forwarding performance.

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Anhydrous rare earth tris(cinnamates) [RE(cinn)3] (RE = La–Lu, Y and Sc and cinnH = trans-cinnamic acid) were prepared by metathesis in water and by direct reaction of the metal with cinnamic acid in a 1,2,4,5-tetramethylbenzene flux at ca. 200 °C. X-ray crystal structure determinations and X-ray powder data show that, in the solid state, the larger lanthanoids (La–Dy) form an isomorphous polymeric series consisting of homoleptic nine-coordinate metal centres bonded to three chelating and bridging tridentate cinnamates. The late REIII cinnamate (RE = Dy, Ho–Lu, Y) complexes also form linear one-dimensional polymeric chains with all RE metal atoms being seven-coordinate. The cinnamates are either bound tridentate bridging in a μ-η2:η1 fashion, or μ-η1:η1syn-syn bidentate bridging. A structural break occurs at dysprosium which has been characterised in both crystallographic forms, and gives solely the late RE form when precipitated at 80 °C. ScIII cinnamate was also isolated as an analytically pure precipitate which was, again, found to be anhydrous in nature. A structural change was identified by powder XRD between the late REIII cinnamates and ScIII cinnamate.

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Purpose – The purpose of this paper is to focus on the differences between managing domestic corporate brands (DCBs) and multinational corporate brands (MCBs), and presents a framework highlighting six types of complexity associated with managing both forms of corporate brands in an international business context.

Design/methodology/approach – This paper proposes a framework addressing six types of complexity involved in managing DCBs and MCBs drawing on the literature related to corporate branding, corporate brands, and domestic and multinational corporations. The six types of complexity examined include: strategic role, organisational structure, culture, knowledge, positioning and extended responsibility.

Findings – The research identifies that DCBs have a lower degree of complexity in regard to strategic role, knowledge and positioning, but have a higher level in regard to organisational structure, cultural and extended responsibility complexity. MCBs face more complexity than DCBs across all dimensions because they operate across business environments and need to coordinate activities while adapting to environmental differences.

Practical implications – The findings highlight the importance of environmental complexity for firms managing brands globally. The issues of complexity identified in this paper need to be understood if firms are to effectively build and manage their corporate brands within and across markets.

Originality/value – The paper highlights the concepts of DCBs and MCBs, and identifies the factors that contribute to the complexity of managing these two types of corporate brands domestically and internationally.

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Telepractice is rapidly gaining popularity as a cost-effective and convenient alternative to in-person services for a range of speech-language pathology (SLP) applications. To date, there has been little research investigating the use of telepractice to support families with a new speech generating device (SGD). This paper reports on the outcomes of a novel online training and support program, trialed with 4 underserviced Australian families of children with a new SGD. The program consisted of 6 video-narrated lessons on SGD use, along with an online supervision and practice component conducted via videoconference. Semistructured interviews were undertaken with parents following their completion of the program. Parents noted the telepractice support model offered a range of benefits, including convenient service access and flexible learning options. Challenges included technology limitations and increased pressure on parents to coordinate home practice. Overall, parents reported that the telepractice program was a positive experience for them and their children. Findings indicated that telepractice is a promising mode of service delivery for those learning to use a new SGD. Further research in this area is warranted.

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This paper presents a new distributed multi-agent scheme for reactive power management in smart coordinated distribution networks with renewable energy sources (RESs) to enhance the dynamic voltage stability, which is mainly based on controlling distributed static synchronous compensators (DSTATCOMs). The proposed control scheme is incorporated in a multi-agent framework where the intelligent agents simultaneously coordinate with each other and represent various physical models to provide information and energy flow among different physical processes. The reactive power is estimated from the topology of distribution networks and with this information, necessary control actions are performed through the proposed proportional integral (PI) controller. The performance of the proposed scheme is evaluated on a 8-bus distribution network under various operating conditions. The performance of the proposed scheme is validated through simulation results and these results are compared to that of conventional PI-based DSTATCOM control scheme. From simulation results, it is found that the distributed MAS provides excellence performance for improving voltage profiles by managing reactive power in a smarter way.

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Smart micro-grids can produce 'renewable' energy and store them in power storage devices. Power loss, however, is a significant problem in power exchange among the micro-grids and between the macro-station and individual micro-grids. To optimally reduce the total power losses in such a power grid system, in this paper, a greedy coalition formation algorithm is proposed, which allows the macro-station to coordinate mutual power exchange among the micro-grids and between each micro-grid and the macro-station. Our algorithm optimizes the total power losses across the entire power grid, including the cost of charging and discharging power storage devices and power losses due to power transfers. The algorithm creates exchange pairs among the micro-grids, giving priority to pairs with higher power loss reduction per exchanged power unit. Through computer-based simulations, we demonstrate that the proposed approach significantly reduces the average power loss compared with the conventional noncooperative method. The simulations also demonstrate that the communications overhead of our proposal (due to negotiations aimed at forming coalitions) does not significantly affect the available communication resource. © 2014 IEEE.

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BACKGROUND: The health care for patients having two or more long-term medical conditions is fragmented between specialists, allied health professionals, and general practitioners (GPs), each keeping separate medical records. There are separate guidelines for each disease, making it difficult for the GP to coordinate care. The TrueBlue model of collaborative care to address key problems in managing patients with multimorbidity in general practice previously reported outcomes on the management of multimorbidities. We report on the care plan for patients with depression, diabetes, and/or coronary heart disease that was embedded in the TrueBlue study. METHODS: A care plan was designed around diabetes, coronary heart disease, and depression management guidelines to prompt implementation of best practices and to provide a single document for information from multiple sources. It was used in the TrueBlue trial undertaken by 400 patients (206 intervention and 194 control) from 11 Australian general practices in regional and metropolitan areas. RESULTS: Practice nurses and GPs successfully used the care plan to achieve the guideline-recommended checks for almost all patients, and successfully monitored depression scores and risk factors, kept pathology results up to date, and identified patient priorities and goals. Clinical outcomes improved compared with usual care. CONCLUSION: The care plan was used successfully to manage and prioritise multimorbidity. Downstream implications include improving efficiency in patient management, and better health outcomes for patients with complex multimorbidities.

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Electronic Medical Records (EMR) are increasingly used for risk prediction. EMR analysis is complicated by missing entries. There are two reasons - the “primary reason for admission” is included in EMR, but the co-morbidities (other chronic diseases) are left uncoded, and, many zero values in the data are accurate, reflecting that a patient has not accessed medical facilities. A key challenge is to deal with the peculiarities of this data - unlike many other datasets, EMR is sparse, reflecting the fact that patients have some, but not all diseases. We propose a novel model to fill-in these missing values, and use the new representation for prediction of key hospital events. To “fill-in” missing values, we represent the feature-patient matrix as a product of two low rank factors, preserving the sparsity property in the product. Intuitively, the product regularization allows sparse imputation of patient conditions reflecting common comorbidities across patients. We develop a scalable optimization algorithm based on Block coordinate descent method to find an optimal solution. We evaluate the proposed framework on two real world EMR cohorts: Cancer (7000 admissions) and Acute Myocardial Infarction (2652 admissions). Our result shows that the AUC for 3 months admission prediction is improved significantly from (0.741 to 0.786) for Cancer data and (0.678 to 0.724) for AMI data. We also extend the proposed method to a supervised model for predicting of multiple related risk outcomes (e.g. emergency presentations and admissions in hospital over 3, 6 and 12 months period) in an integrated framework. For this model, the AUC averaged over outcomes is improved significantly from (0.768 to 0.806) for Cancer data and (0.685 to 0.748) for AMI data.

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The reaction of lanthanoid chlorides or nitrates with sodium 3-(4′-hydroxyphenyl)propionate (Na4hpp) in methanol or water has yielded complexes [La4(4hpp)12(H2O)6]·4H2O·MeOH (1), [Ce2(4hpp)6(H2O)3]·(H2O)·2.5(EtOH) (2a) (after crystallization from ethanol), [Ho(4hpp)3(H2O)2] (5), [Er(4hpp)3(H2O)2]·1.5(H2O) (6), and [Lu(4hpp)3]·H2O crystal composition (7), as well as heterobimetallics [NaCe2(4hpp)7(H2O)2]·3(H2O) (2b), [NaPr2(4hpp)7(H2O)2]·3(H2O) (3), and [NaNd2(4hpp)7(H2O)(MeOH)]·(H2O)·3(MeOH) (4). The structures of homometallic complexes 1, 2a, 6, and 7 reveal one-dimensional coordination polymers and vividly illustrate the effect of lanthanoid contraction with a decline in coordination numbers in the series from 9-11 (1), 9,10 (2a), 8 (6) to 7 (7) through variations in carboxylate coordination and ligation of water. Bimetallic complexes 2a and 4 each exhibit five different carboxylate binding modes as well as coordination of the 4-OH substituent of 4hpp to sodium thereby linking 1D polymer chains into a 2D network with both 9 and 10 coordinate Ln atoms and 6 coordinate sodium. Bulk products after drying lose solvent of crystallization in some cases (2a, 6), or exchange MeOH for water (4). X-ray powder diffraction indicates that bulk 2b and 3 are isotypic, as are bulk 5 and 6. In contrast to the excellent corrosion protection of lanthanum 4-hydroxycinnamate, compound 1 is ineffective in preventing the corrosion of mild steel, thereby establishing the importance of the -CHCH- structural unit of the former in its anti-corrosion properties. However the flexible -CH2-CH2- chain of the 4hpp ligand enables the crystal engineering of its lanthanoid complexes in a wide variety of structures as well as effective crystallization for structure determination, whereas the analogous 4-hydroxycinnamates have so far evaded structural characterization except for Ln = La, Ce owing to crystallization problems.