51 resultados para GRoVar protocol (Geographic Routing with Variable transmission range)


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Density-based means have been recently proposed as a method for dealing with outliers in the stream processing of data. Derived from a weighted arithmetic mean with variable weights that depend on the location of all data samples, these functions are not monotonic and hence cannot be classified as aggregation functions. In this article we establish the weak monotonicity of this class of averaging functions and use this to establish robust generalisations of these means. Specifically, we find that as proposed, the density based means are only robust to isolated outliers. However, by using penalty based formalisms of averaging functions and applying more sophisticated and robust density estimators, we are able to define a broader family of density based means that are more effective at filtering both isolated and clustered outliers. © 2014 Elsevier Inc. All rights reserved.

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Wireless mesh networks are widely applied in many fields such as industrial controlling, environmental monitoring, and military operations. Network coding is promising technology that can improve the performance of wireless mesh networks. In particular, network coding is suitable for wireless mesh networks as the fixed backbone of wireless mesh is usually unlimited energy. However, coding collision is a severe problem affecting network performance. To avoid this, routing should be effectively designed with an optimum combination of coding opportunity and coding validity. In this paper, we propose a Connected Dominating Set (CDS)-based and Flow-oriented Coding-aware Routing (CFCR) mechanism to actively increase potential coding opportunities. Our work provides two major contributions. First, it effectively deals with the coding collision problem of flows by introducing the information conformation process, which effectively decreases the failure rate of decoding. Secondly, our routing process considers the benefit of CDS and flow coding simultaneously. Through formalized analysis of the routing parameters, CFCR can choose optimized routing with reliable transmission and small cost. Our evaluation shows CFCR has a lower packet loss ratio and higher throughput than existing methods, such as Adaptive Control of Packet Overhead in XOR Network Coding (ACPO), or Distributed Coding-Aware Routing (DCAR).

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Roll forming is a cost and energy efficient process for the manufacture of Ultra High Strength Steel (UHSS) structural and crash components in the automotive industry. The conventional roll forming process is limited to component having constant cross-section, while the recently deveoped Flexible Roll Forming (FRF) process allows the production of components in which the section varies over the length of the aprt; this permits optimization in terms of strength and weight. There has been an uptake in FRF in the heavy vehicle industry for the production of long and high strength structural parts, but passenger car bodies are more complex and generally parts require variations in width and also in depth. The widespread application of FRF in the automotive industy therefore requires the forming of components that have intricate variations in profile depth over the length of the part.
This work is a first comprehensive study of the FRF of high strength structural components with variable depth. For this, the FRF of an automotive bumper section is analyzed numerically using the commercial software package COPRA® FEA RF. A detailed analysis of the distribution and history of plastic strain in longitudinal, transcerse and thickness directions is performed and related to the shape defects observed in the proecss. The analysis shows that when forming variable depth components, zones of compressive longitudinal strain exist that lead to wrinkling defects. These can be reduced by applying additional flange contact during the operation. In general the current work suggests that the FRF of high strength components with variable depth is possible and can compete with other forming methods currently used in the automotive industry.

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In this paper, by using a novel approach, we first prove a new generalization of discrete-type Halanay inequality. Based on our new generalized inequality, a novel criterion for the exponential stability of a certain class of nonlinear non-autonomous difference equations is proposed. Numerical examples are given to illustrate the effectiveness of the obtained results.

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Sensor nodes are closely tied with their geographic location and their connectivity. In recent years many routing protocols have been developed to provide efficient strategy. But most of them are either focus on the geographic proximity or on connectivity. However in sparse network, Geographic routing would fail at local dead ends where a node has no neighbour closer to destination. In contrast, connectivity-based routing may result in non-optimal path and overhead management. In this paper we designed a scalable and distributed routing protocol, GeoConnect, which considers geographic proximity and connectivity for choosing next hop. In GeoConnecl, we construct a new naming system that integrates geographic and connectivity information into a node identification. We use dissimilarity function to compute the dissimilarity and apply a distributed routing algorithm to route packets. The experimental results show that GeoConnect routing provides robust and better performance than sole geographic routing or connectivity routing.

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Multicast is an important mechanism in modern wireless networks and has attracted significant efforts to improve its performance with different metrics including throughput, delay, energy efficiency, etc. Traditionally, an ideal loss-free channel model is widely used to facilitate routing protocol design. However, the quality of wireless links would be affected or even jeopardized by many factors like collisions, fading or the noise of environment. In this paper, we propose a reliable multicast protocol, called CodePipe, with advanced performance in terms of energy-efficiency, throughput and fairness in lossy wireless networks. Built upon opportunistic routing and random linear network coding, CodePipe not only simplifies transmission coordination between nodes, but also improves the multicast throughput significantly by exploiting both intra-batch and inter-batch coding opportunities. In particular, four key techniques, namely, LP-based opportunistic routing structure, opportunistic feeding, fast batch moving and inter-batch coding, are proposed to offer substantial improvement in throughput, energy-efficiency and fairness. We evaluate CodePipe on ns2 simulator by comparing with other two state-of-art multicast protocols, MORE and Pacifier. Simulation results show that CodePipe significantly outperforms both of them.

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Multicast is an important mechanism in modern wireless networks and has attracted significant efforts to improve its performance with different metrics including throughput, delay, energy efficiency, etc. Traditionally, an ideal loss-free channel model is widely used to facilitate routing protocol design. However, the quality of wireless links is affected or even jeopardized resulting in transmission failures by many factors like collisions, fading or the noise of environment. In this paper, we propose a reliable multicast protocol, called CodePipe, with energy-efficiency, high throughput and fairness in lossy wireless networks. Building upon opportunistic routing and random linear network coding, CodePipe can not only eliminate coordination between nodes, but also improve the multicast throughput significantly by exploiting both intra-batch and inter-batch coding opportunities. In particular, four key techniques, namely, LP-based opportunistic routing structure, opportunistic feeding, fast batch moving and inter-batch coding, are proposed to offer significant improvement in throughput, energy-efficiency and fairness.Moreover, we design an efficient online extension of CodePipe such that it can work in a dynamic network where nodes join and leave the network as time progresses. We evaluate CodePipe on ns2 simulator by comparing with other two state-of-art multicast protocols,MORE and Pacifier. Simulation results show that CodePipe significantly outperforms both of them.

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Objective: To compare protocol-directed sedation management with traditional non-protocol-directed practice in mechanically ventilated patients. Design: Randomized, controlled trial. Setting: General intensive care unit (24 beds) in an Australian metropolitan teaching hospital. Patients: Adult, mechanically ventilated patients (n = 312). Interventions: Patients were randomly assigned to receive sedation directed by formal guidelines (protocol group, n = 153) or usual local clinical practice (control, n = 159). Measurements and Main Results: The median (95% confidence interval) duration of ventilation was 79 hrs (56-93 hrs) for patients in the protocol group compared with 58 hrs (44-78 hrs) for patients who received control care (p = .20). Lengths of stay (median [range]) in the intensive care unit (94 [2-1106] hrs vs. 88 (14-962) hrs, p = .58) and hospital (13 [1-113] days vs. 13 (1-365) days, p = .97) were similar, as were the proportions of subjects receiving a tracheostomy (17% vs. 15%, p = .64) or undergoing unplanned self-extubation (1.3% vs. 0.6%, p = .61). Death in the intensive care unit occurred in 32 (21%) patients in the protocol group and 32 (20%) control subjects (p = .89), with a similar overall proportion of deaths in hospital (25% vs. 22%, p = .51). A Cox proportional hazards model, after adjustment for age, gender, Acute Physiology and Chronic Health Evaluation II score, diagnostic category, and doses of commonly used drugs, estimated that protocol sedation management was associated with a 22% decrease (95% confidence interval 40% decrease to 2% increase, p = .07) in the occurrence of successful weaning from mechanical ventilation. Conclusions: This randomized trial provided no evidence of a substantial reduction in the duration of mechanical ventilation or length of stay, in either the intensive care unit or the hospital, with the use of protocol-directed sedation compared with usual local management. Qualified high-intensity nurse staffing and routine Australian intensive care unit nursing responsibility for many aspects of ventilatory practice may explain the contrast between these findings and some recent North American studies. (C) 2008 Lippincott Williams & Wilkins, Inc.

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Radio Frequency Identification (RFID) system is a remote identification technology which is taking the place of barcodes to become electronic tags of an object. However, its radio transmission nature is making it vulnerable in terms of security. Recently, research proposed that an RFID tag can contain malicious code which might spread viruses, worms and other exploits to middleware and back-end systems. This paper is proposing a framework which will provide protection from malware and ensure the data privacy of a tag. The framework will use a sanitization technique with a mutual authentication in the reader level. This will ensure that any malicious code in the tag is identified. If the tag is infected by malicious code it will stop execution of the code in the RFIF system. Here shared unique parameters are used for authentication. It will be capable of protecting an RFID system from denial of service (DOS) attack, forward security and rogue reader better than existing protocols. The framework is introducing a layer concept on a smart reader to reduce coupling between different tasks. Using this framework, the RFID system will be protected from malware and also the privacy of the tag will be ensured.

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BACKGROUND: Australian farming communities have up to twice the suicide rate of the general population. Men, particularly, demonstrate debilitating self- and perceived-stigma associated with an experience of suicide. The Ripple Effect is aimed to reduce suicide stigma within the social, cultural, geographical and psychological contexts in which it occurs.

METHODS: A mixed-method design with multi-level evaluation will be effected following the development and delivery of a personalised website experience (combining shared stories, education, personal goal setting and links to resources) to farming men, aged 30-64 years, with an experience of suicide. Pre- and post-surveys will be used to assess changes in self- and perceived-stigma and suicide literacy. Online feedback from participants and semi-structured interviews during follow-up will be thematically analysed.

DISCUSSION: This project will provide information about increasingly accessible, innovative approaches to reducing the debilitating health and wellbeing effects of suicide stigma on a population of Australia's farmers.

TRIAL REGISTRATION: This research protocol was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR) (ACTRN: ACTRN12616000289415 ) on 7(th) March, 2016.

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Eel culture is solely dependent on wild seed stock, caught in estuaries during the freshwater migratory phase as glass eels. The methods used for weaning glass eels are very variable, and range from the use of live zooplankton to fish roe to fines of commercial fish feeds. The present experiments were conducted on glass eels of the Australian shortfin eel, when the effectiveness of four types of readily available fish roe (European carp, mirror dory, orange roughy and warehou) were evaluated over a 42-day period, in the laboratory.

After 28 days the eels did not show an interest in orange roughy and mirror dory roe, and these two treatments were discontinued to avoid mortality. In all treatments there was a decrease in mean weight during this period, but the survival was over 99%. In the 28th to 42nd day period the mean weight and specific growth rate of glass eels reared on European carp and warehou roe increased, but the differences between these two treatments were not significant.

The physical features of the roe and the oocytes thereof, the proximate composition, amino acid and fatty acid composition indicated major differences amongst the roe types, particularly with regard to the amount of n−6 polyunsaturated fatty acids (PUFA) and the ratio of n−3 to n−6. European carp and warehou roe (and oocytes) had a significantly higher arachidonic acid (AA-20:4n−6; over 60% of PUFA) content and a considerably lower n−3 to n−6 ratio (n−3 to n−6 ratio being 1.32, 5.92, 3.77 and 2.67 for roe types, and 1.25, 4.83, 2.91 and 2.42 for oocytes, of European carp, mirror dory, orange roughy and warehou, respectively), than in the other two roe types. The fatty acid profiles of European carp and warehou roe were similar to that of metamorphosing glass eels.