33 research outputs found

    In-Network Video Quality Adaption using Packet Trimming at the Edge

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    This paper describes the effects of running innetwork quality adaption by trimming the packets of layered video streams at the edge. The video stream is transmitted using the BPP transport protocol, which is like UDP, but has been designed to be both amenable to trimming and to provide low-latency and high reliability. The traffic adaption uses the Packet Wash process of BPP on the transmitted Scalable Video Coding (SVC) video streams as they pass through a network function which is BPP-aware and embedded at the edge. Our previous work has either demonstrated the use of SDN controllers to directly implement Packet Wash, or the use of a network function in the core of the network to do the same task. This paper presents the first attempt to deploy and evaluate such a process in the edge. We compare the performance of transmitting video using BPP and the Packet Wash trimming, against alternative transmission schemes, namely TCP, UDP, and HTTP Adaptive Streaming (HAS). The results demonstrate that providing traffic engineering using in-network quality adaption using packet trimming, provides high quality at the receiver

    Towards High Precision End-to-End Video Streaming from Drones using Packet Trimming

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    The emergence of a number of network communication facilities such as Network Function Virtualization (NFV), Software Defined Networking (SDN), the Internet of Things (IoT), Unmanned Aerial Vehicles (UAV), and in-network packet processing, holds a potential to meet the low latency, high precision requirements of various future multimedia applications. However, this raises the corresponding issues of how all of these elements can be used together in future networking environments, including newly developed protocols and techniques. This paper describes the architecture of an end-to-end video streaming platform for video surveillance, consisting of a UAV network domain, an edge server implementing in-network packet trimming operations with the use of Big Packet Protocol (BPP), utilization of Scalable Video Coding (SVC) and multiple video clients which connect to a network managed by an SDN controller. A Virtualized Edge Function at the drone edge utilizes SVC and in communication with the Drone Control Unit to manage the transmitted video quality. Experimental results show the potential that future multimedia applications can achieve the required high precision with the use of future network components and the consideration of their interactions

    Lab-Scale Study of the Calcium Carbonate Dissolution and Deposition by Marine Cyanobacterium Phormidium subcapitatum

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    Suggestions that calcification in marine organisms changes in response to global variations in seawater chemistry continue to be advanced (Wilkinson, 1979; Degens et al. 1985; Kazmierczak et al. 1986; R. Riding 1992). However, the effect of [Na+] on calcification in marine cyanobacteria has not been discussed in detail although [Na+] fluctuations reflect both temperature and sea-level fluctuations. The goal of these lab-scale studies therefore was to study the effect of environmental pH and [Na+] on CaCO3 deposition and dissolution by marine cyanobacterium Phormidium subcapitatum. Marine cyanobacterium P. subcapitatum has been cultivated in ASN-III medium. [Ca2+] fluctuations were monitored with Ca(2+) probe. Na(+) concentrations were determined by the initial solution chemistry. It was found that the balance between CaCO3 dissolution and precipitation induced by P. subcapitatum grown in neutral ASN III medium is very close to zero. No CaCO3 precipitation induced by cyanobacterial growth occurred. Growth of P. subcapitatum in alkaline ASN III medium, however, was accompanied by significant oscillations in free Ca(2+) concentration within a Na(+) concentration range of 50-400 mM. Calcium carbonate precipitation occurred during the log phase of P. subcapitatum growth while carbonate dissolution was typical for the stationary phase of P. subcapitatum growth. The highest CaCO3 deposition was observed in the range of Na(+) concentrations between 200-400 mM. Alkaline pH also induced the clamping of P. subcapitatum filaments, which appeared to have a strong affinity to envelop particles of chemically deposited CaCO3 followed by enlargement of those particles size. EDS analysis revealed the presence of Mg-rich carbonate (or magnesium calcite) in the solution containing 10-100 mM Na(+); calcite in the solution containing 200 mM Na(+); and aragonite in the solution containing with 400 mM Na(+). Typical present-day seawater contains xxmM Na(+). Early (Archean) seawater was likely less saline. The division of marine cyanobacterium P. subcapitatum is associated with periodic deposition and dissolution of CaCO3, the rhythms and intensity of which are dependent on concentrations of both OH(-) and Na(+). Thus, the role of present-day marine cyanobacteria in the global carbonate cycle might be reduced to aggregation and recrystallization of available CaCO3 particles in marine water rather than long-term precipitation and accumulation of CaCO3 deposits. For lower Na(+) concentrations, precipitation of carbonates by cyanobacteria would be even less significant. These results suggest that the lack of calcified cyanobacteria in stromatalite-bearing Precambrian sequences can be explained not only by high dissolved inorganic carbon concentrations but also by lower salinity, as well as possible lower pH compared to present-day oceans

    Prevalence and risk factors of allergies in turkey (PARFAIT): Results of a multicentre cross-sectional study in adults

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    The Prevalence and Risk Factors of Allergies in Turkey (PARFAIT) study was planned to evaluate the prevalence of and risk factors for asthma and allergic diseases in Turkey. The present analysis used data from 25,843 parents of primary school children, obtained from a cross-sectional questionnaire-based study. A total of 25,843 questionnaires from 14 centres were evaluated. In rural areas, the prevalences asthma, wheezing, allergic rhinitis and eczema in males were: 8.5% (95% confidence interval (CI) 7.9-9.1%), 13.5% (95% CI 12.8-14.2%), 17.5% (95% CI 16.7-18.2%) and 10.8% (95% CI 10.211.4%), respectively; and in females were: 11.2% (95% CI 10.9-11.8%), 14.7% (95% CI 14.315.1%), 21.2% (95% CI 20.4-22.0%) and 13.1% (95% CI 2.4-13.8%), respectively. In urban areas, the corresponding prevalences in males were: 6.2% (95% CI 5.8-6.6%), 10.8% (95% CI 10.311.3%), 11.7% (95% CI 11.4-12.0%) and 6.6% (95% CI 6.2-7.0%), respectively; and in females were: 7.5 % (95% CI 7.9-7.1%), 12.0% (95% CI 11.7-12.3%), 17.0% (95% CI 16.4-17.6%) and 7.3% (95% CI 6.9-7.7%), respectively. Having an atopic first-degree relative or any other atopic diseases had significant effects on the prevalence of allergic diseases. Housing conditions, such as living in a shanty-type house, visible moulds at home and use of wood or biomass as heating or cooking material were associated with one or more allergic diseases. Although genetic susceptibility is strongly associated, country-and population-based environmental factors may contribute to increased prevalence rates of allergic diseases. Copyright © ERS Journals Ltd 2009

    Individualised prediction of drug resistance and seizure recurrence after medication withdrawal in people with juvenile myoclonic epilepsy: A systematic review and individual participant data meta-analysis

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    Summary Background A third of people with juvenile myoclonic epilepsy (JME) are drug-resistant. Three-quarters have a seizure relapse when attempting to withdraw anti-seizure medication (ASM) after achieving seizure-freedom. It is currently impossible to predict who is likely to become drug-resistant and safely withdraw treatment. We aimed to identify predictors of drug resistance and seizure recurrence to allow for individualised prediction of treatment outcomes in people with JME. Methods We performed an individual participant data (IPD) meta-analysis based on a systematic search in EMBASE and PubMed – last updated on March 11, 2021 – including prospective and retrospective observational studies reporting on treatment outcomes of people diagnosed with JME and available seizure outcome data after a minimum one-year follow-up. We invited authors to share standardised IPD to identify predictors of drug resistance using multivariable logistic regression. We excluded pseudo-resistant individuals. A subset who attempted to withdraw ASM was included in a multivariable proportional hazards analysis on seizure recurrence after ASM withdrawal. The study was registered at the Open Science Framework (OSF; https://osf.io/b9zjc/). Findings  368) was predicted by an earlier age at the start of withdrawal, shorter seizure-free interval and more currently used ASMs, resulting in an average internal-external cross-validation concordance-statistic of 0·70 (95%CI 0·68–0·73). Interpretation We were able to predict and validate clinically relevant personalised treatment outcomes for people with JME. Individualised predictions are accessible as nomograms and web-based tools. Funding MING fonds

    ВИЗНАЧЕННЯ ШИРИНИ ЗАБАРОНЕНОЇ ЗОНИ НАПІВПРОВІДНИКОВОГО МАТЕРІАЛУ В ГОТОВОМУ ВИРОБІ

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    The paper puts forward a method for determination of semiconductor activation energy in end product. It is illustrated that band gap can be calculated at cutoffs on both axes of graphs ln(I)÷U, measured at different temperatures. Minimum temperature interval is determined depending on measuring accuracy. A new method for determination of value Eg without VAC (volt-ampere characteristics) extrapolation is put forward.Предложен метод определения энергии активации полупроводника в готовом изделии. Показано, что ширину запрещённой зоны можно рассчитать по отсечкам на обеих осях графиков ln(I)÷U, измеренных при разных температурах. Определён минимальный температурный интервал в зависимости от точности измерений. Указан новый способ определения величины E g без экстраполяции ВАХ.Запропоновано метод визначення енергії активації напівпровідника в готовому виробі. Показано, що ширину забороненої зони можливо розрахувати по відсічкам на обох осях графіків ln(I)÷U, виміряних при різних температурах. Визначений мінімальний температурний інтервал в залежності від точності вимірювань. Вказано новий засіб визначення E g без екстраполяції ВАХ

    Epidemiology of adult food allergies in turkey: A multicenter study

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    European-Academy-of-Allergology-and-Clinical-Immunology Digital Congress (EAACI) -- JUN 06-08, 2020 -- London, ENGLANDWOS: 000566847300479[No abstract available]European Acad Allergol Clin Immuno

    Prevalence of aspirin-exacerbated respiratory disease in patients with asthma in Turkey: A cross-sectional survey

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    Background: There are no country-based data focused on aspirin (ASA)-exacerbated respiratory disease (AERD) in Turkey. Objective: To assess the prevalence of AERD in adult patients with asthma
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