28 research outputs found

    Efficient Data Gathering and Aggregation for Multiple Applications in Wireless Sensor Networks

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    Data aggregation in wireless sensor networks refers to acquiring the sensed data from the sensors to the gateway node. It reduces the amount of power consumed during data transmission between the sensor nodes. Generally homomorphic encryptions have been applied to conceal communication during aggregation. Since enciphered data can be aggregated algebraically without decryption. Here adversaries are able to forge aggregated results by compromising them. However, these schemes are not satisfying multi-application environments, provide insecure transmission and do not provide secure counting for unauthorized aggregation attacks. In this paper, we propose a new concealed data aggregation scheme extended from homomorphic privacy encryption system. The proposed scheme designed for a multi-application environment, mitigates the impact of compromising attacks in single application environments and also it can avoid the damage from unauthorized aggregations by the privacy homomorphic encryption scheme.Comment: 14 pages, 4 figure

    A review of forest fire surveillance technologies: Mobile ad-hoc network routing protocols perspective

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    Mobile Ad-Hoc Network (MANET) is a type of structure-less wireless mobile network, in which each node plays the role of the router and host at the same time. MANET has gained increased interest from researchers and developers for various applications such as forest fire detection. Forest fires require continuous monitoring and effective communication, technology, due to the big losses are brought about by this event. As such, disaster response and rescue applications are considered to be a key application of the MANET. This paper gives an extensive review of the modern techniques used in the forest fire detection based on recent MANET routing protocols such as reactive Location-Aided Routing (LAR), proactive Optimized Link State Routing (OLSR) and LAR-Based Reliable Routing Protocol (LARRR)

    Optimization of Knitted Fabrics for better Thermo-Physiological Comfort by using Taguchi-based Principal Component Analysis

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    The water, air permeability and thermal resistance of fabrics are important attributes that have a significant impact on the thermal comfort properties of sportswear fabrics in different environmental conditions. In this work, terry and fleece fabrics were developed by varying the fibre content and mass per unit area of fabrics. Moreover, the thermo-physical properties of the developed fabrics, including air permeability, water vapor permeability and thermal resistance, were analysed before and after washing. The multi-response optimization of the thermal comfort properties of knitted fabrics was performed using principal component analysis (PCA) and the Taguchi signal-to-noise ratio (PCA-S/N ratio) to achieve optimal properties. It was determined that the selected parameters (fabric type, finishing, fibre content and fabric mass per unit area) had a significant effect on the thermal comfort properties of knitted fabrics. The PCA analysis showed that 100% cotton terry fabric before washing with an aerial weight of 220 g/m2 had higher air and water vapor permeability value, but a lower thermal resistance value

    Fungal Planet description sheets: 1436–1477

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    Novel species of fungi described in this study include those from various countries as follows: Argentina, Colletotrichum araujiae on leaves, stems and fruits of Araujia hortorum. Australia, Agaricus pateritonsus on soil, Curvularia fraserae on dying leaf of Bothriochloa insculpta, Curvularia millisiae from yellowing leaf tips of Cyperus aromaticus, Marasmius brunneolorobustus on well-rotted wood, Nigrospora cooperae from necrotic leaf of Heteropogon contortus, Penicillium tealii from the body of a dead spider, Pseudocercospora robertsiorum from leaf spots of Senna tora, Talaromyces atkinsoniae from gills of Marasmius crinis-equi and Zasmidium pearceae from leaf spots of Smilax glyciphylla. Brazil, Preussia bezerrensis from air. Chile, Paraconiothyrium kelleni from the rhizosphere of Fragaria chiloensis subsp. chiloensis f. chiloensis. Finland, Inocybe udicola on soil in mixed forest with Betula pendula, Populus tremula, Picea abies and Alnus incana. France, Myrmecridium normannianum on dead culm of unidentified Poaceae. Germany, Vexillomyces fraxinicola from symptomless stem wood of Fraxinus excelsior. India, Diaporthe limoniae on infected fruit of Limonia acidissima, Didymella naikii on leaves of Cajanus cajan, and Fulvifomes mangroviensis on basal trunk of Aegiceras corniculatum. Indonesia, Penicillium ezekielii from Zea mays kernels. Namibia, Neocamarosporium calicoremae and Neocladosporium calicoremae on stems of Calicorema capitata, and Pleiochaeta adenolobi on symptomatic leaves of Adenolobus pechuelii. Netherlands, Chalara pteridii on stems of Pteridium aquilinum, Neomackenziella juncicola (incl. Neomackenziella gen. nov.) and Sporidesmiella junci from dead culms of Juncus effusus. Pakistan, Inocybe longistipitata on soil in a Quercus forest. Poland, Phytophthora viadrina from rhizosphere soil of Quercus robur, and Septoria krystynae on leaf spots of Viscum album. Portugal (Azores), Acrogenospora stellata on dead wood or bark. South Africa, Phyllactinia greyiae on leaves of Greyia sutherlandii and Punctelia anae on bark of Vachellia karroo. Spain, Anteaglonium lusitanicum on decaying wood of Prunus lusitanica subsp. lusitanica, Hawksworthiomyces riparius from fluvial sediments, Lophiostoma carabassense endophytic in roots of Limbarda crithmoides, and Tuber mohedanoi from calcareus soils. Spain (Canary Islands), Mycena laurisilvae on stumps and woody debris. Sweden, Elaphomyces geminus from soil under Quercus robur. Thailand, Lactifluus chiangraiensis on soil under Pinus merkusii, Lactifluus nakhonphanomensis and Xerocomus sisongkhramensis on soil under Dipterocarpus trees. Ukraine, Valsonectria robiniae on dead twigs of Robinia hispida. USA, Spiralomyces americanus (incl. Spiralomyces gen. nov.) from office air. Morphological and culture characteristics are supported by DNA barcodes

    Herd Immunity against Severe Acute Respiratory Syndrome Coronavirus 2 Infection in 10 Communities, Qatar.

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    We investigated what proportion of the population acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and whether the herd immunity threshold has been reached in 10 communities in Qatar. The study included 4,970 participants during June 21-September 9, 2020. Antibodies against SARS-CoV-2 were detected by using an electrochemiluminescence immunoassay. Seropositivity ranged from 54.9% (95% CI 50.2%-59.4%) to 83.8% (95% CI 79.1%-87.7%) across communities and showed a pooled mean of 66.1% (95% CI 61.5%-70.6%). A range of other epidemiologic measures indicated that active infection is rare, with limited if any sustainable infection transmission for clusters to occur. Only 5 infections were ever severe and 1 was critical in these young communities; infection severity rate of 0.2% (95% CI 0.1%-0.4%). Specific communities in Qatar have or nearly reached herd immunity for SARS-CoV-2 infection: 65%-70% of the population has been infected

    Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

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    SummaryBackground Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatoryactions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19.Methods In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospitalwith COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients wererandomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once perday by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatmentgroups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment andwere twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants andlocal study staff were not masked to the allocated treatment, but all others involved in the trial were masked to theoutcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treatpopulation. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936.Findings Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) wereeligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomlyallocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall,561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days(rate ratio 0·97, 95% CI 0·87–1·07; p=0·50). No significant difference was seen in duration of hospital stay (median10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days(rate ratio 1·04, 95% CI 0·98–1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, nosignificant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilationor death (risk ratio 0·95, 95% CI 0·87–1·03; p=0·24).Interpretation In patients admitted to hospital with COVID-19, azithromycin did not improve survival or otherprespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restrictedto patients in whom there is a clear antimicrobial indication

    Fiscal Adjustment in Sudan

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    The paper aims to identify the optimal size, speed and composition of the medium-term fiscal adjustment in the context of Sudan''s limited oil reserves. The permanently sustainable non-oil primary balance approach suggests the need for significant fiscal adjustment over the medium term, requiring a widening of the tax base. Cross-country comparisons highlight VAT and personal income tax (as well as tax administration) as key areas for reform. The paper also suggests the need for complementary expenditure-side measures in the areas of petroleum pricing and anchoring fiscal policy in non-oil indicators.Fiscal reforms;Economic models;Government expenditures;Income taxes;Oil producing countries;Oil revenues;Oil sector;Tax administration;Tax systems;Value added tax;tax rates, fiscal adjustment, oil producing, fiscal policy, budget constraint, public debt, oil production, petroleum pricing, taxation, fiscal indicators, tax base, oil reserves, oil prices, fiscal consolidation, structural fiscal, increases in tax rates, fiscal stance, fuel prices, tax revenue, fiscal federalism, tax increases, tax policy, tax increase, oil companies, petroleum sector, fiscal performance, crude oil, government expenditure, ex-refinery price, tax collections, tax system, fiscal structure, refinery price, expenditure policy, structural fiscal reforms, revenue collection, oil producers, petroleum company, pipeline cost, tax effort, oil-producing countries, oil pipelines, oil company, fiscal effort, world oil prices, public spending, tax revenues, key fiscal indicators, public finance, fiscal reform, petroleum corporation, petroleum prices, fiscal decentralization, fiscal aggregates, petroleum exploration, structural fiscal reform, petroleum production, fiscal balances, fiscal reporting, oil- producing countries, fiscal position, oil quality, fiscal risk, fiscal deficits, oil resources, fiscal targets, expenditure adjustments, fiscal revenues, government revenue, national budget, oil exporting countries, fiscal terms, fiscal resources, accumulation of arrears, oil fields, fiscal savings, pipeline company, natural resources, oil pipeline, fiscal expenditure, tax burden, fiscal policy formulation, fiscal sustainability, increase in expenditures, budget deficit, refined products, oil and gas, spending cuts, fiscal solvency, petroleum products, primary fiscal balance, taxpayer office, tax administrations, fiscal analysis, oil exploration, production sharing contracts, capital expenditures, crude oil pipelines, fiscal balance, tax collection, fiscal deficit, fiscal reform program, natural gas, fiscal situation, fiscal burden, oil exports, oil exporters, fuel consumption

    Cluster-based data dissemination, cluster head formation under sparse, and dense traffic conditions for vehicular ad hoc networks

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    Information and communication technologies have changed the way of operations in all fields. These technologies also have adopted for wireless communication and provide low cost and convenient solutions. Vehicular ad hoc networks are envisioned with their special and unique intercommunication systems to provide safety in intelligent transportation systems and support large-size networks. Due to dense and sparse traffic conditions, routing is always a challenging task to establish reliable and effective communication among vehicle nodes in the highly transportable environment. Several types of routing protocols have been proposed to handle high mobility and dynamic topologies including topology-based routing, position and geocast routing, and cluster-based routing protocols. Cluster-based routing is one of the feasible solutions for vehicular networks due to its manageable and more viable nature. In cluster-based protocols, the network is divided into many clusters and each cluster selects a cluster head for data dissemination. In this study, we investigate the current routing challenges and trend of cluster-based routing protocols. In addition, we also proposed a Cluster-based Routing for Sparse and Dense Networks to handle dynamic topologies, the high-mobility of vehicle nodes. Simulation results show a significant performance improvement of the proposed protocol
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