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Reporting application at SDC : A low bandwidth mobile applicationVesterlund, Elias January 2014 (has links)
The objective of the report is to investigate which kind of mobile appli-cation, native, hybrid or web, that is the best regarding cross-platform support compared to development cost. As there are little information regarding pure web applications for mobile devices a prototype will be constructed to give light in this technology. The prototype should an-swer the questions if it can save a year's usage in the cell phones memory, if it is possible to have support for 100 percent of Sweden area and generally if this approach would suffice. There are also some physi-cal restrictions on the web application. A login must be done in less than 5 second, fetch TOs( timber orders) within 10 seconds, report a row within 5 seconds. This in a 2G environment, in Telias network, which is mostly likely to be used in the forest. To easily test the application the CPN-tools(colored petri nets) are used to graphically model the applica-tion and simulations are thereafter done to get a scenes how the applica-tion would perform during many years of usage. To construct have been constructed with the aid of open web technologies as HTML5,CSS4, JavaScript, JQuery and JQuery mobile. The prototype used asynchronies communication to mask loss of coverage and long loading times. It also utilized HTML5 localStorage to save TOs and employer information so that minimize the need for fetching information many times. The proto-type application cannot be used in 100 percent of Sweden's area because the cellular coverage is not present in big areas in the north of Sweden. Therefore information is stored locally but after the pre fetched work orders are completed new work orders must be fetched where cellular coverage is present. The application still have a big usage area and as most wood products comes from the middle of Sweden this cannot be seen as a big problem. To save a year's usage of data on the other hand is not a problem at all. About 10 percent of the available 5 MB of storage in the HTML5 localStorage would be needed. It did also with ease handle the time limitations. As a conclusion the need for a web applica-tion, for SDC, is only present if both IVR and web reporting through a computer is if these services are liquidated in the long run. There are a bit more work with creating a hybrid native/web application using third-party applications but it in turns would give a better coverage area as that kind of application can pre download all TOs and employers ignoring any limitations in storage. This is not possible to do as a pure web application can't be run in the background on the phone.
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Multiscale local polynomial transforms in smoothing and density estimationAmghar, Mohamed 22 December 2017 (has links)
Un défi majeur dans les méthodes d'estimation non linéaire multi-échelle, comme le seuillage des ondelettes, c'est l'extension de ces méthodes vers une disposition où les observations sont irrégulières et non équidistantes. L'application de ces techniques dans le lissage de données ou l'estimation des fonctions de densité, il est crucial de travailler dans un espace des fonctions qui impose un certain degré de régularité. Nous suivons donc une approche différente, en utilisant le soi-disant système de levage. Afin de combiner la régularité et le bon conditionnement numérique, nous adoptons un schéma similaire à la pyramide Laplacienne, qui peut être considérée comme une transformation d'ondelettes légèrement redondantes. Alors que le schéma de levage classique repose sur l'interpolation comme opération de base, ce schéma permet d'utiliser le lissage, en utilisant par exemple des polynômes locaux. Le noyau de l'opération de lissage est choisi de manière multi-échelle. Le premier chapitre de ce projet consiste sur le développement de La transformée polynomiale locale multi-échelle, qui combine les avantages du lissage polynomial local avec la parcimonie de la décomposition multi-échelle. La contribution de cette partie est double. Tout d'abord, il se concentre sur les largeurs de bande utilisées tout au long de la transformée. Ces largeurs de bande fonctionnent comme des échelles contrôlées par l'utilisateur dans une analyse multi-échelle, ce qui s'explique par un intérêt particulier dans le cas des données non-équidistantes. Cette partie présente à la fois une sélection de bande passante optimale basée sur la vraisemblance et une approche heuristique rapide. La deuxième contribution consiste sur la combinaison du lissage polynomial local avec les préfiltres orthogonaux dans le but de diminuer la variance de la reconstruction. Dans le deuxième chapitre, le projet porte sur l'estimation des fonctions de densité à travers la transformée polynomiale locale multi-échelle, en proposant une reconstruction plus avancée, appelée reconstruction pondérée pour contrôler la propagation de la variance. Dans le dernier chapitre, On s’intéresse à l’extension de la transformée polynomiale locale multi-échelle dans le cas bivarié, tout en énumérant quelques avantages qu'on peut exploiter de cette transformée (la parcimonie, pas de triangulations), comparant à la transformée en ondelette classique en deux dimension. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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BANDBREDDSREDOVISNING : Sammansättning av bandbreddsövervakningslösning för företagsmiljö / BANDWIDTH ACCOUNTING : Composition of bandwidth monitoring solution for business environmentLindberg, Daniel, Olsson, Kristoffer January 2017 (has links)
Företaget Hi5 är i behov av en lösning som kan övervaka bandbreddsanvändningen till ochfrån deras verksamhet. Denna lösning ska kunna mäta använd trafik per IP över tid.Företaget vill ha denna lösning för att i framtiden kunna ha möjligheten att, med data somunderlag, debitera kunder som passerar en avtalad gräns för bandbreddsanvändning.Lösningen ska även ge Hi5 en överblick över all trafik till och från företaget.Denna rapport beskriver sammansättningen av en sådan lösning med hjälp av färdigatjänster och verktyg. Lösningen består av fyra moduler: pmacct, pmacct-to-elasticsearch,Elasticsearch och Grafana. ● Pmacct agerar insamlingsdel som fångar och aggregerar trafikdata.● Pmacct-to-elasticsearch fungerar som en brygga och flyttar data från pmacct till Elasticsearch.● Elasticsearch är backend-delen i lösningen som lagrar och organiserar data iindexfiler.● Grafana, frontend-delen, hämtar data från Elasticsearch och visualiserar denna iform av grafer och tabeller. Resultatet av arbetet är att Hi5 fick en lösning som uppfyllde deras önskemål, där kundersbandbreddsanvändning kan mätas och presenteras i ett användarvänligt gränssnitt. / The company Hi5 is in need of a solution that can monitor the bandwidth usage to and from their operations. This solution should be able to measure used traffic per IP over time. The company wants this solution in order to be able to, in the future, have the data needed available to charge customers who exceeds an agreed upon bandwidth limit. The solution should also give Hi5 an overview of all traffic from and to the company.This report describes the composition of such a solution using completed services and tools. The solution consists of four modules: pmacct, pmacct-to-elasticsearch, Elasticsearch and Grafana. ● Pmacct acts as the collector that catches and aggregates traffic data.● Pmacct-to-elasticsearch works as a bridge and moves the data from pmacct to Elasticsearch.● Elasticsearch is the backend part of the solution that stores and organizes the data in index files.● Grafana, the frontend, collects the data from Elasticsearch and visualizes it in the form of graphs and tables. The result of the project is that Hi5 got a solution that fulfilled their wishes, where customer’s bandwidth usage can be measured and presented in a user-friendly interface.
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Efficient Bandwidth Management for Ethernet Passive Optical NetworksElrasad, Amr 15 May 2016 (has links)
The increasing bandwidth demands in access networks motivates network operators, networking devices manufacturers, and standardization institutions to search for new approaches for access networks. These approaches should support higher bandwidth, longer distance between end user and network operator, and less energy consumption.
Ethernet Passive Optical Network (EPON) is a favorable choice for broadband access networks. EPONs support transmission rates up to 10 Gbps. EPONs also support distance between end users and central office up to 20 Km. Moreover, optical networks have the least energy consumption among all types of networks.
In this dissertation, we focus on reducing delay and saving energy in EPONs. Reducing delay is essential for delay-sensitive traffic, while minimizing energy consumption is an environmental necessity and also reduces the network operating costs. We identify five challenges, namely excess bandwidth allocation, frame delineation, congestion resolution, large round trip time delay in long-reach EPONs (LR-EPONs), and energy saving. We provide a Dynamic Bandwidth Allocation (DBA) approach for each challenge. We also propose a novel scheme that combines the features of the proposed approaches in one highly performing scheme.
Our approach is to design novel DBA protocols that can further reduce the delay and be simultaneously simple and fair. We also present a dynamic bandwidth allocation scheme for Green EPONs taking into consideration maximizing energy saving under target delay constraints.
Regarding excess bandwidth allocation, we develop an effective DBA scheme called
Delayed Excess Scheduling (DES). DES achieves significant delay and jitter reduction and is more suitable for industrial deployment due to its simplicity. Utilizing DES in hybrid TDM/WDM EPONs (TWDM-EPONs) is also investigated. We also study eliminating the wasted bandwidth due to frame delineation. We develop an interactive DBA scheme, Efficient Grant Sizing Interleaved Polling (EGSIP), to compensate the unutilized bandwidth due to frame delineation. Our solution achieves delay reduction ratio up to 90% at high load. We also develop a Congestion Aware Limited Time (CALT) DBA scheme to detect and resolve temporary congestion in EPONs. CALT smartly adapts the optical networking unit (ONU) maximum transmission window according to the detected congestion level. Numerical results show that CALT is more robust at high load compared to other related published schemes.
Regarding LR-EPONs, the main concern is large round trip delay mitigation. We address two problems, namely bandwidth over-granting in Multi-Thread Polling (MTP) and on-the-fly void filling. We combine, with some modifications, EGSIP and DES to resolve bandwidth over-granting in MTP. We also manage to adaptively tune MTP active running threads along with the offered load. Regarding on-the-fly void filling, Our approach, Parallel Void Thread (PVT), achieves large delay reduction for delay-sensitive traffic. PVT is designed as a plus function to DBA and can be combined with almost all DBA schemes proposed before. The powerful feature of our proposed solutions is integrability. We integrate our solutions together and form a multi-feature, robust, fairly simple, and well performing DBA scheme over LR-TWDM-EPONs.
Our final contribution is about energy saving under target delay constraints. We tackle the problem of downstream based sleep time sizing and scheduling under required delay constraints. Simulation results show that our approach adheres to delay constraints and achieves almost ideal energy saving ratio at the same time.
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Monitorování přenosových parametrů sítě Internet / Monitoring of communication properties in InternetIľko, Pavol January 2016 (has links)
This thesis deals with measuring transmission parameters of the Internet network, in particular latency of ping, SSH protocol and bandwidth. The thesis is divided into a theoretical and a practical part. Theoretical part describes PlanetLab network, its brief history and contemporary projects. At the same time, tools for data mining from web pages are described. These information obtained from the theoretical part are used for creating PlanetLab nodes list and for programming applications which measure the network transmission parameters. Applications, list of nodes and obtained data are attached on DVD disc.
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Blixt™ : An Available Bandwidth Measurements’ Approach for High-Speed Mobile NetworksJasim, Al-Hussein Hameed January 2018 (has links)
Mobile networks are in the process of becoming the world’s leading medium for data traffic. This challenge has raised the bar for Quality of Services (QoS) provided by the mobile network operators. It requires methods and tools to verify the Service Level Agreement (SLA) and benchmark competitors by comparing metrics of QoS, e.g. the round-trip time and available bandwidth. For this purpose, Blixt™ has been developed, which is a property of InfoVista Sweden AB. Blixt™ is an Android application which measures the available bandwidth and the round-trip time for the latest generation of mobile networks. Blixt™ approach relies on a time-stamping protocol commonly known as Two-Way Active Measurement Protocol (TWAMP). This research work discusses how the packet probing parameters affect the accuracy of measurements and the level of intrusiveness. The performance of the technique was experimentally tested and compared to other tools and methods, namely, iPerf3, nPerf and FTP test.
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Investigating the future of fixed broadband in Swedish households : How technological and behavioral development will affect the fixed broadband consumption in Swedish households / Utredning av framtidens fasta bredband i svenska hushåll : Hur teknisk och beteendemässig utveckling kommer påverka användningen av fasta bredband i svenska hushållKlöfver, Gunnar January 2016 (has links)
The purpose of this thesis is to investigate how fixed broadband will be used in Swedish households in a 3-6-year perspective. Internet is becoming more and more integrated in peoples everyday lives. Internet is utilized for communication, entertainment and businesses to mention a few, and the areas of use are continuously expanding. How this expansion might affect the household usage patterns and what these possible changes will require from a fixed broadband connection are continuous questions in need of investigation to ensure that ISPs are able to provide services in line with market demand. By studying Internet adoption and consumption behavioral trends combined with development of fixed broadband up until present day, the thesis will serve as a basis for what the future might hold. These findings were then complemented with insights from market active experts together with adjacent research on future broadband connectivity, and compiled into a possible projection for fixed Swedish household broadband. The findings show that, with increasing societal integration, Internet is commonly viewed more and more as a commodity; a societal necessity rather than an, as previously viewed, additional service. Furthermore, the increasing speed trend remains but might wane within 10 years as development further than so, with consistent rate, will heavily exceed any imaginable future bandwidth utilization. Consequently, the idea of a normalized broadband, sufficient for the vast majority of household consumers is discussed as possibility from a 3-6 year perspective. / Syftet med denna studie är att undersöka, i ett 3-6 års perspektiv, hur fast bredband kommer att användas i svenska hushåll. Internet är allt mer integrerat i vårt dagliga liv. Internet används för kommunikation, underhållning och företagande för att nämna några exempel, och användningsområdena är ständigt växande. Hur denna expansion kan påverka hushållens användningsmönster och vad dessa eventuella förändringar kommer att kräva från en fast bredbandsanslutning är kontinuerliga frågor i behov av utredning för att se till att Internetleverantörer kan tillhandahålla tjänster i linje med marknadens efterfrågan. Genom att studera Internetvanor och konsumtionstrender i kombination med utvecklingen av fast bredband fram till idag, skapades en grund för vad framtiden skulle kunna medföra. Dessa slutsatser kompletteras sedan med insikt från marknadsaktiva experter samt med närliggande forskning om framtida bredbandsanvändning, och sammanställdes till en trolig prognos för fast bredband i svenska hushåll. Resultaten visar att med ökande samhällsintegration, ses Internet allt mer som en grundläggande samhällstjänst snarare än en, som det hittills betraktats, privat tilläggstjänst som man väljer eller avstår ifrån av olika anledningar. Utvecklingen mot ännu snabbare bredband fortsätter, men bör avta inom 10 år då utveckling längre än så i samma takt kommer grovt överskrida all tänkbar framtida bandbreddsutnyttjande. Följaktligen diskuteras möjligheten av ett normaliserat bredband, omfattande nog för majoriteten av alla hushållsanvändare inom ett 3-6 års perspektiv.
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Vector Measurements for Wireless Network DevicesZenteno, Efrain January 2013 (has links)
Wireless networks are an iconic technology of today’s modern era, theyare present in our daily activities as can be exemplified by cellular communications,wi-fi, bluetooth, and others. Vector measurements play an importantrole in the design, simulation, and testing of wireless networks and are usedto characterize key devices operating in the radio interface, such as amplifiers,filters, and mixers.Accurate characterization is the key for improving the capacity and efficiencyof wireless networks. As the demand for network capacity continuouslyincreases, the accuracy of vector measurements must also improve. Further,it is anticipated that such trends will continue in the years to come. Consequently,the wireless industry needs to include nonlinear behavior in theircharacterization and analysis, to assess and guaranty the operation of the devices,and to comply to the specifications from governmental regulations. Incontrast to linear behavior, nonlinear behavior presents an additional bandwidthrequirement because the signal bandwidth grows when it passes throughnonlinear devices. In this thesis, vector measurements for devices operatingin wireless networks are studied, emphasizing a synthetic approach for theinstrumentation. This approach enables the use of digital post-processing algorithms,which enhances the measurement accuracy and/or speed and canovercome hardware impairments. This thesis presents the design of a vectorialmeasurement system for wireless devices considering the aforementionedtrends and requirements. It also explores the advantages of the proposedapproach, describes its limitations, and discusses the digital signal processingalgorithms used to reach its final functionality. Finally, measurement resultsof the proposed setup are presented, analyzed and compared to those of modernindustrial instruments. / <p>QC 20130204</p>
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Compensation de l'erreur de bande passante dans les convertisseurs analogique numérique à entrelacement temporel / Bandwidth mismatch calibration in time-interleaved analog-to-digital convertersGhanem, Fatima 28 September 2012 (has links)
La problématique traitée dans la thèse consiste à concevoir des convertisseurs très larges bandes pour les applications stations de base. Le choix d'une architecture à entrelacement temporel a été fait et permet d’augmenter la vitesse des convertisseurs tout en ayant un contrôle sur la consommation. Cependant, les canaux constituant cette architecture évoluent différemment à des variations d'environnement. En conséquence, des erreurs d’appariement entre les canaux dégradent les performances du convertisseur parallèle. Les erreurs les plus connues sont : l’offset, le gain, l’erreur de phase des horloges d’échantillonnage qui sont largement traitées dans la littérature et enfin, l'erreur de bande passantes entre les filtres d'entrées des convertisseurs. Les travaux de la thèse ont permis de proposer des solutions d'estimation et de correction de cette erreur de bande passante afin d'améliorer les performance en linéarité du convertisseur. De plus les techniques de calibrage proposées sont validées à l'aide de circuits réels. / Time-interleaved converter (ti-adc) is an efficient way to increase the speed while maintaining a good accuracy. it consists of the parallelization of several channels; each one running at lower speed. The benefit of this approach is to increase the conversion bandwidth without increasing the power. however, mismatches between the channels cause errors at the digital output and degrade the linearity and the resolution of the system. Gain, offset and clock skew errors are widely treated and we have been interested on bandwidth mismatch error which appears at high frequencies. The goal of the thesis is to develop and implement background calibration techniques for bandwidth mismatch error in a high speed ti-adc (up to 500 msps) in order to achieve a 90 db of sfdr for high input frequencies (up to 385mhz) and up to 94 db at low frequencies. An analog correction solution based on randomization was proposed and a new estimation technique based on gain extraction was implemented and validated for wideband signal.
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A novel technique for phased array receivers based on an economic sampling schemeBlanco Moro, Rodrigo 04 September 2013 (has links)
Phased array systems present desirable antenna features like beam steering and high gain. However, due to their high cost, civilian applications cannot generally afford them, restricting their usage to military. Hardware involved in phased array systems is expensive and the number of devices is high, since there is usually one device of each kind (filter, amplifier, shifter..) for each individual antenna. Alternative techniques, mainly based on TDMA, have been developed looking for lowering the number of elements in the system. However, these approaches increase the system bandwidth, multiplying it by a factor of $N$ (Number of antennas), as they use redundant information.
In this thesis, a novel phased receiver, based on an economic sampling scheme is proposed. All the elements in an array receive a common information (signal amplitude) and a unique information (relative delay between elements). The idea is to sample only the information required to reconstruct the transmitted signal and discard the redundant one. This idea is achieved by sampling just one antenna during each RF cycle and then gathering all the information taking in account the relative delay between different antenna elements.
The proposed technique is mathematically proved and validated by simulation. As a first approach, the equation for the received signal in the frequency domain is derived for a linear array. The radiation pattern and the received signals are simulated for equally spaced planar and linear arrays. Bandwidth signal transmission is demonstrated and tapering effects are shown. After that, the proposed technique is expanded for arbitrary structures and the resulting system bandwidth is enhanced by using different sampling order sequences. / Master of Science
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