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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Proyecto Neuro Help

Chávez Ruiz, Sebastián Gonzalo, Cullas Antizana, Gonzalo Andre, García Bertorini, Hugo Marco, López Quevedo, Angie Gianella 25 November 2020 (has links)
En el presente documento se presentará la idea de negocio Neuro Help, ofreciendo un servicio online personalizado de consultas psicológicas en la especialidad de Neuropsicología. Mediante métodos de investigación, tales como entrevistas, focus groups y encuestas; se plantearon hipótesis para corroborar la viabilidad del proyecto. Igualmente, se buscará analizar el entorno interno como fortalezas y debilidades; y el entorno externo, que son factores los cuales no tenemos control alguno. Asimismo, la identificación del mercado objetivo es importante y por ello también se hizo un estudio de este para comprender a donde se dirigirán los esfuerzos de ventas, teniendo en cuenta sus necesidades y los problemas que le aquejan. Por ello, teniendo conocimiento de la situación actual del país y la viabilidad que tendría el proyecto, mediante un análisis financiero, se confirmará la escalabilidad en el mercado y el cumplimiento de los objetivos tanto a corto, mediano y largo plazo; asegurando un crecimiento e impacto sostenible con el transcurrir de los años. / This document will present the business idea of Neuro Help, an online service of psychology consultations in the specialist of neurology. Through different Market research methods such as interviews, focus groups and surveys; it was proposed different hypotheses in order to corroborate the viability of the business. Also, we will seek to analyze the internal environment such as strengths and weaknesses; and the external environment, uncontrollable factors that can affect the business development. In addition, seeking to understand the market that will surround us, we will investigate in which segment will be the target to which the sales efforts will be directed, knowing the different problems that they have throughout social networks. Therefore, knowing what it is really going on with the country and the entire world, and the viability of the business; we will confirm the scalability in the market and accomplishing with different strategies in short, medium and long term, ensuring a sustainable growing over the years. / Trabajo de investigación
312

Architectural Evolution of Intelligent Transport Systems (ITS) using Cloud Computing

Nasim, Robayet January 2015 (has links)
With the advent of Smart Cities, Intelligent Transport System (ITS) has become an efficient way of offering an accessible, safe, and sustainable transportation system. Utilizing advances in Information and Communication Technology (ICT), ITS can maximize the capacity of existing transportation system without building new infrastructure. However, in spite of these technical feasibilities and significant performance-cost ratios, the deployment of ITS is limited in the real world because of several challenges associated with its architectural design. This thesis studies how to design a highly flexible and deployable architecture for ITS, which can utilize the recent technologies such as - cloud computing and the publish/subscribe communication model. In particular, our aim is to offer an ITS infrastructure which provides the opportunity for transport authorities to allocate on-demand computing resources through virtualization technology, and supports a wide range of ITS applications. We propose to use an Infrastructure as a Service (IaaS) model to host large-scale ITS applications for transport authorities in the cloud, which reduces infrastructure cost, improves management flexibility and also ensures better resource utilization. Moreover, we use a publish/subscribe system as a building block for developing a low latency ITS application, which is a promising technology for designing scalable and distributed applications within the ITS domain. Although cloud-based architectures provide the flexibility of adding, removing or moving ITS services within the underlying physical infrastructure, it may be difficult to provide the required quality of service (QoS) which decrease application productivity and customer satisfaction, leading to revenue losses. Therefore, we investigate the impact of service mobility on related QoS in the cloud-based infrastructure. We investigate different strategies to improve performance of a low latency ITS application during service mobility such as utilizing multiple paths to spread network traffic, or deploying recent queue management schemes. Evaluation results from a private cloud testbed using OpenStack show that our proposed architecture is suitable for hosting ITS applications which have stringent performance requirements in terms of scalability, QoS and latency. / Baksidestext: Intelligent Transport System (ITS) can utilize advances in Information and Communication Technology (ICT) and maximize the capacity of existing transportation systems without building new infrastructure. However, in spite of these technical feasibilities and significant performance-cost ratios, the deployment of ITS is limited in the real world because of several challenges associated with its architectural design.  This thesis studies how to design an efficient deployable architecture for ITS, which can utilize the advantages of cloud computing and the publish/subscribe communication model. In particular, our aim is to offer an ITS infrastructure which provides the opportunity for transport authorities to allocate on-demand computing resources through virtualization technology, and supports a wide range of ITS applications. We propose to use an Infrastructure as a Service (IaaS) model to host large-scale ITS applications, and to use a publish/subscribe system as a building block for developing a low latency ITS application. We investigate different strategies to improve performance of an ITS application during service mobility such as utilizing multiple paths to spread network traffic, or deploying recent queue management schemes. / <p>Artikel 4 Network Centric Performance Improvement for Live VM Migration finns i avhandlingen som manuskript. Nu publicerat konferenspaper. </p>
313

A scalable database for a remote patient monitoring system

Mukhammadov, Ruslan January 2013 (has links)
Today one of the fast growing social services is the ability for doctors to monitor patients in their residences. The proposed highly scalable database system is designed to support a Remote Patient Monitoring system (RPMS). In an RPMS, a wide range of applications are enabled by collecting health related measurement results from a number of medical devices in the patient’s home, parsing and formatting these results, and transmitting them from the patient’s home to specific data stores. Subsequently, another set of applications will communicate with these data stores to provide clinicians with the ability to observe, examine, and analyze these health related measurements in (near) real-time. Because of the rapid expansion in the number of patients utilizing RPMS, it is becoming a challenge to store, manage, and process the very large number of health related measurements that are being collected. The primary reason for this problem is that most RPMSs are built on top of traditional relational databases, which are inefficient when dealing with this very large amount of data (often called “big data”). This thesis project analyzes scalable data management to support RPMSs, introduces a new set of open-source technologies that efficiently store and manage any amount of data which might be used in conjunction with such a scalable RPMS based upon HBase, implements these technologies, and as a proof of concept, compares the prototype data management system with the performance of a traditional relational database (specifically MySQL). This comparison considers both a single node and a multi node cluster. The comparison evaluates several critical parameters, including performance, scalability, and load balancing (in the case of multiple nodes). The amount of data used for testing input/output (read/write) and data statistics performance is 1, 10, 50, 100, and 250 GB. The thesis presents several ways of dealing with large amounts of data and develops &amp; evaluates a highly scalable database that could be used with a RPMS. Several software suites were used to compare both relational and non-relational systems and these results are used to evaluate the performance of the prototype of the proposed RPMS. The results of benchmarking show that MySQL is better than HBase in terms of read performance, while HBase is better in terms of write performance. Which of these types of databases should be used to implement a RPMS is a function of the expected ratio of reads and writes. Learning this ratio should be the subject of a future thesis project. / En av de snabbast växande sociala tjänsterna idag är möjligheten för läkare att övervaka patienter i sina bostäder. Det beskrivna, mycket skalbara databassystemet är utformat för att stödja ett sådant Remote Patient Monitoring-system (RPMS). I ett RPMS kan flertalet applikationer användas med hälsorelaterade mätresultat från medicintekniska produkter i patientens hem, för att analysera och formatera resultat, samt överföra dem från patientens hem till specifika datalager. Därefter kommer ytterligare en uppsättning program kommunicera med dessa datalager för att ge kliniker möjlighet att observera, undersöka och analysera dessa hälsorelaterade mått i (nära) realtid. På grund av den snabba expansionen av antalet patienter som använder RPMS, är det en utmaning att hantera och bearbeta den stora mängd hälsorelaterade mätningar som samlas in. Den främsta anledningen till detta problem är att de flesta RPMS är inbyggda i traditionella relationsdatabaser, som är ineffektiva när det handlar om väldigt stora mängder data (ofta kallat "big data"). Detta examensarbete analyserar skalbar datahantering för RPMS, och inför en ny uppsättning av teknologier baserade på öppen källkod som effektivt lagrar och hanterar godtyckligt stora datamängder. Dessa tekniker används i en prototypversion (proof of concept) av ett skalbart RPMS baserat på HBase. Implementationen av det designade systemet jämförs mot ett RPMS baserat på en traditionell relationsdatabas (i detta fall MySQL). Denna jämförelse ges för både en ensam nod och flera noder. Jämförelsen utvärderar flera kritiska parametrar, inklusive prestanda, skalbarhet, och lastbalansering (i fallet med flera noder). Datamängderna som används för att testa läsning/skrivning och statistisk prestanda är 1, 10, 50, 100 respektive 250 GB. Avhandlingen presenterar flera sätt att hantera stora mängder data och utvecklar samt utvärderar en mycket skalbar databas, som är lämplig för användning i RPMS. Flera mjukvaror för att jämföra relationella och icke-relationella system används för att utvärdera prototypen av de föreslagna RPMS och dess resultat. Resultaten av dessa jämförelser visar att MySQL presterar bättre än HBase när det gäller läsprestanda, medan HBase har bättre prestanda vid skrivning. Vilken typ av databas som bör väljas vid en RMPS-implementation beror därför på den förväntade kvoten mellan läsningar och skrivningar. Detta förhållande är ett lämpligt ämne för ett framtida examensarbete.
314

A new Content Distribution Network architecture - PlentyCast

Cao, Wei Qiu January 2004 (has links)
Content Distribution Networks have existed for some years. They involve the following problem domains and have attracted attention both in academic research and industry: content replica placement, content location and routing, swarm intelligence, and overlay network self-organization for this type of distributed system. In this project, we propose a novel Content Distribution Network architecture – PlentyCast. This study focuses on improving access latency, network scalability, high content availability, low bandwidth consumption, and improving infrastructure performance for Content Distribution Networks. Outstanding problems such as: Flash crowd, DoS, and difficulty of traffic engineering due to Peer-to-Peer are addressed. / Mediadistributionsnätverk har funnits några år. De har fått uppmärksamhet i både akademisk forskning och i industrin och kännetecknas av följande frågor: placering av innehållskopior, lokalisering av innehåll och routing, svärm intelligens, överlagrade nätverks självorganisering för denna typ av fördelade system. I denna rapport studeras en ny nätverksarkitektur för innehållsfördelning - PlentyCast. Denna studie fokuserar på tillgångslatens, nätverksskalbarhet, hög innehållstillgång, låg bandbreddskonsumtion, och förbättrad infrastrukturprestanda för Innehållsfördelningsnätverk.
315

Scalable location-temporal range query processing for structured peer-to-peer networks / Traitement de requêtes spatio-temporelles pour les réseaux pair-à-pair structurés

Cortés, Rudyar 06 April 2017 (has links)
La recherche et l'indexation de données en fonction d'une date ou d'une zone géographique permettent le partage et la découverte d'informations géolocalisées telles que l'on en trouve sur les réseaux sociaux comme Facebook, Flickr, ou Twitter. Cette réseau social connue sous le nom de Location Based Social Network (LBSN) s'applique à des millions d'utilisateurs qui partagent et envoient des requêtes ciblant des zones spatio-temporelles, permettant d'accéder à des données géolocalisées générées dans une zone géographique et dans un intervalle de temps donné. Un des principaux défis pour de telles applications est de fournir une architecture capable de traiter la multitude d'insertions et de requêtes spatio-temporelles générées par une grande quantité d'utilisateurs. A ces fins, les Tables de Hachage Distribué (DHT) et le paradigme Pair-à-Pair (P2P) sont autant de primitives qui forment la base pour les applications de grande envergure. Cependant, les DHTs sont mal adaptées aux requêtes ciblant des intervalles donnés; en effet, l'utilisation de fonctions de hachage sacrifie la localité des données au profit d'un meilleur équilibrage de la charge. Plusieurs solutions ajoutent le support de requêtes ciblant des ensembles aux DHTs. En revanche ces solutions ont tendance à générer un nombre de messages et une latence élevée pour des requêtes qui ciblent des intervalles. Cette thèse propose deux solutions à large échelle pour l'indexation des données géolocalisées. / Indexing and retrieving data by location and time allows people to share and explore massive geotagged datasets observed on social networks such as Facebook, Flickr, and Twitter. This scenario known as a Location Based Social Network (LBSN) is composed of millions of users, sharing and performing location-temporal range queries in order to retrieve geotagged data generated inside a given geographic area and time interval. A key challenge is to provide a scalable architecture that allow to perform insertions and location-temporal range queries from a high number of users. In order to achieve this, Distributed Hash Tables (DHTs) and the Peer-to-Peer (P2P) computing paradigms provide a powerful building block for implementing large scale applications. However, DHTs are ill-suited for supporting range queries because the use of hash functions destroy data locality for the sake of load balance. Existing solutions that use a DHT as a building block allow to perform range queries. Nonetheless, they do not target location-temporal range queries and they exhibit poor performance in terms of query response time and message traffic. This thesis proposes two scalable solutions for indexing and retrieving geotagged data based on location and time.
316

Optimization and virtualization techniques adapted to networking / Des techniques d’optimisation et de virtualisation adaptées aux réseaux

Ibn Khedher, Hatem 30 April 2018 (has links)
Dans cette thèse, on présente nos travaux sur la virtualisation dans le contexte de la réplication des serveurs de contenu vidéo. Les travaux couvrent la conception d’une architecture de virtualisation pour laquelle on présente aussi plusieurs algorithmes qui peuvent réduire les couts globaux à long terme et améliorer la performance du système. Le travail est divisé en plusieurs parties : les solutions optimales, les solutions heuristiques pour des raisons de passage à l’échelle, l’orchestration des services, l’optimisation multi-objective, la planification de services dans des réseaux actifs et complexes et l'intégration d'algorithmes dans une plate-forme réelle / In this thesis, we designed and implemented a tool which performs optimizations that reduce the number of migrations necessary for a delivery task. We present our work on virtualization in the context of replication of video content servers. The work covers the design of a virtualization architecture for which there are also several algorithms that can reduce overall costs and improve system performance. The thesis is divided into several parts: optimal solutions, greedy (heuristic) solutions for reasons of scalability, orchestration of services, multi-objective optimization, service planning in complex active networks, and integration of algorithms in real platform. This thesis is supported by models, implementations and simulations which provide results that showcase our work, quantify the importance of evaluating optimization techniques and analyze the trade-off between reducing operator cost and enhancing end user satisfaction index
317

Intergiciel sémantique pour la recherche des services de l'internet des objets / Semantic-based middleware for IoT service search

Ben Fredj, Sameh 27 October 2014 (has links)
Avec l’avènement de l’Internet des Objets, nous sommes confrontés à une prolifération des appareils connectés répartis sur des emplacements physiques, appelés des espaces intelligents et qui offrent des services de l’Internet des Objets. La découverte simple et transparente de ces services est cruciale pour le succès de l’Internet des Objets. Les caractéristiques des services de l’Internet des objets, tels que leur nombre, leur hétérogénéité et leur dynamicité induite par la mobilité des appareils connectés, rendent leur découverte difficile. Dans cette thèse, nous proposons une architecture de système et ses mécanismes associés pour permettre une découverte efficace et scalable des services de l’Internet des Objets, en se basant sur le Web Sémantique et en supportant des contextes dynamiques. Notre approche repose sur les passerelles distribuées qui intègrent des mécanismes de regroupement, d’agrégation de l’information et de routage sémantique. / With the advent of the Internet of Things (IoT), we are facing a proliferation of connected devices distributed over physical locations, so called smart spaces and offering IoT services. Enabling an easy and seamless discovery of these IoT services is crucial for the success of the Internet of Things. The characteristics of IoT services, such as their sheer number, their heterogeneity and their dynamicity induced by the mobility of the related devices, make discovering them a challenge. In this thesis, we propose a system architecture and the associated mechanisms to enable efficient and scalable semantic-based IoT service discovery supporting dynamic contexts. Our approach relies on distributed semantic gateways that embed clustering, information aggregation and semantic routing mechanisms.
318

Relativistic Causal Ordering A Memory Model for Scalable Concurrent Data Structures

Triplett, Josh 01 January 2012 (has links)
High-performance programs and systems require concurrency to take full advantage of available hardware. However, the available concurrent programming models force a difficult choice, between simple models such as mutual exclusion that produce little to no concurrency, or complex models such as Read-Copy Update that can scale to all available resources. Simple concurrent programming models enforce atomicity and causality, and this enforcement limits concurrency. Scalable concurrent programming models expose the weakly ordered hardware memory model, requiring careful and explicit enforcement of causality to preserve correctness, as demonstrated in this dissertation through the manual construction of a scalable hash-table item-move algorithm. Recent research on "relativistic programming" aims to standardize the programming model of Read-Copy Update, but thus far these efforts have lacked a generalized memory ordering model, requiring data-structure-specific reasoning to preserve causality. I propose a new memory ordering model, "relativistic causal ordering", which combines the scalabilty of relativistic programming and Read-Copy Update with the simplicity of reader atomicity and automatic enforcement of causality. Programs written for the relativistic model translate to scalable concurrent programs for weakly-ordered hardware via a mechanical process of inserting barrier operations according to well-defined rules. To demonstrate the relativistic causal ordering model, I walk through the straightforward construction of a novel concurrent hash-table resize algorithm, including the translation of this algorithm from the relativistic model to a hardware memory model, and show through benchmarks that the resulting algorithm scales far better than those based on mutual exclusion.
319

A Peer-to-Peer Networking Framework for Scalable Massively Multiplayer Online Game Development in Unity

Forsbacka, Jakob, Sollenius, Gustav January 2023 (has links)
This thesis investigates designing and implementing a peer-to-peer (P2P) networking frameworkfor Unity, a popular game engine, intending to offer a scalable and efficient solution forconstructing networked multiplayer games. The research covers an analysis of a P2P networkarchitecture, transport layer protocols, challenges in NAT traversal, and peer list management.A framework is proposed, incorporating NAT traversal, remote procedural calls (RPC), synchronization variables (SyncVar), interest management (IM), and a lobby system. The framework’sperformance is evaluated through integration, network, and game performance tests. Resultsdemonstrate the framework’s capacity to accommodate up to 50 players, with a theoreticalmaximum of 200 players, but further optimization techniques could increase this limit. IMsolutions are suggested to improve scalability, rendering the framework a more viable optionfor MMOGs. Additionally, this thesis seeks to contribute to comprehending P2P networkingframework design and implementation for Unity while emphasizing potential directions forfuture research and how they should be optimized / Denna uppsats undersöker design och implementering av ett peer-to-peer (P2P) nätverksramverk för Unity, en populär spelmotor, med målet att erbjuda en skalbar och effektiv lösning för att bygga nätverksbaserade flerspelarspel. Uppsatsen omfattar en analys av P2P-nätverksarkitektur, transportlagerprotokoll, utmaningar vid NAT-Travesering och hantering av peerlistor. Ett ramverk som inkluderar NAT-Travesering, fjärrproceduranrop (RPC), synkroniseringsvariabler (SyncVar), Interest Management (IM) och ett lobby-system föreslås. Ramverkets prestanda utvärderas genom integrationstester, nätverksprestandatester och spel-prestandatester. Resultaten visar att ramverket kan hantera upp till 50 spelare, med en teoretisk maximal kapacitet på 200 spelare, men ytterligare optimiserings tekniker kan öka denna gränsen. IM-lösningar föreslås för att förbättra skalbarheten, vilket gör ramverket till ett bättre alternativ för MMOG. Dessutom syftar denna uppsats till att bidra till förståelsen för design och implementering av P2P-nätverksramverk för Unity, samtidigt som den betonar potentiella riktningar för framtida forskning och hur dessa ska kunna optimeras.
320

Designing an indoor modular micro-farm / Design av modulär mikrofarm för inomhusbruk

DEACONU, RADU COSMIN January 2020 (has links)
This thesis is a product design and engineering master’s project that has been carried out in partnership with a swedish product design and greentech company. In this project, an array of data gathering and design methods were used with the goal of developing a modular solution for an indoor hydroponic micro-farm. The project also investigates the benefits and consequences of designing this type of product in this fashion. A secondary goal was set, as discovered through the research and analysis process. This goal was to investigate the possible impact that a self-sustaining microfarm has on the UX of growing plants and how it can be addressed. / Detta är en masteruppsats i produktutveckling och teknik som har utförts i samarbete med ett svenskt företag med fokus på grön teknologi. Projektet använder sig av flera typer av metoder för datainsamling och design för att ta fram en modulär lösning för en hydroponisk mikromiljö för inomhusbruk. Projektet undersöker vilka fördelar och eventuella konsekvenser en sådan typ av design för med sig. Under analysens gång har ett bimål tagits fram, nämligen att undersöka vilken möjlig påverkan en självdrivande mikromiljö har på användarupplevelsen av att ta hand om växter samt hur detta kan adresseras.

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