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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.
161

An Intelligent and Powerful Data Plane Support To Enhance Future Communication

Arumaithurai, Mayutan 01 November 2018 (has links)
No description available.
162

Ljus i mörker - design som imiterar perceptionen av dagsljus inomhus

Axelsson, Erika January 2019 (has links)
På jordklotets nordliga breddgrader påverkas människor av mörka säsonger med liten tillgång till dagsljus, med fysiska påföljder så som sömnproblem och energibrist. Problemet kan minskas med ljuskällor som kan imitera soldygnet men dessa produkter lämnar föga åt fantasin. Denna studie har undersökt möjligheten att genom produktdesign imitera nordbors perception av dagsljus inomhus för att erbjuda användaren en emotionell upplevelse. Genom användarcentrerad design och kvalitativa metoder sammanställdes empiriska data för att skapa en samlad bild av nordbors perception av dagsljus inomhus. Studiens teoretiska ramverk berörde även ljusdesign och framför allt human-centric lighting samt ludisk design. Studien visar att det är av stor vikt att erbjuda individanpassning i denna typ av produkt för att förse användaren med en emotionell upplevelse. Slutkonceptet är en takarmatur för hemmet som erbjuder användaren lekfull design och interaktion, möjlighet att återskapa dygnsrytm samt en imitation av den egna perceptionen av dagsljus. / On the northern latitudes of the globe, people are affected by dark seasons with little access to daylight, with physical effects such as problems sleeping and loss of energy. The problems can be reduced with light sources that can imitate the sun, but these products leave little to the imagination.This study has investigated the possibility of imitating northerners’ perception of daylight indoors through product design to offer the user an emotional experience. Through user-centered design and qualitative methods, empirical data were compiled to create a unified image of northerners’ perception of daylight indoors. The study's theoretical framework also included lighting design, above all, human-centric lighting and ludic design.The study shows that it is of great importance to offer individual customization in this kind of product in order to provide the user with an emotional experience. The final concept is a light fixture for the home that offers the user playful design and interaction, the opportunity to recreate the circadian rhythm and an imitation of one's own perception of daylight.
163

Improving Resilience of Communication in Information Dissemination for Time-Critical Applications

Deshmukh, Rajvardhan Somraj 02 July 2019 (has links)
Severe weather impacts life and in this dire condition, people rely on communication, to organize relief and stay in touch with their loved ones. In such situations, cellular network infrastructure\footnote{We refer to cellular network infrastructure as infrastructure for the entirety of this document} might be affected due to power outage, link failures, etc. This urges us to look at Ad-hoc mode of communication, to offload major traffic partially or fully from the infrastructure, depending on the status of it. We look into threefold approach, ranging from the case where the infrastructure is completely unavailable, to where it has been replaced by make shift low capacity mobile cellular base station. First, we look into communication without infrastructure and timely, dissemination of weather alerts specific to geographical areas. We look into the specific case of floods as they affect significant number of people. Due to the nature of the problem we can utilize the properties of Information Centric Networking (ICN) in this context, namely: i) Flexibility and high failure resistance: Any node in the network that has the information can satisfy the query ii) Robust: Only sensor and car need to communicate iii) Fine grained geo-location specific information dissemination. We analyze how message forwarding using ICN on top of Ad hoc network, approach compares to the one based on infrastructure, that is less resilient in the case of disaster. In addition, we compare the performance of different message forwarding strategies in VANETs (Vehicular Adhoc Networks) using ICN. Our results show that ICN strategy outperforms the infrastructure-based approach as it is 100 times faster for 63\% of total messages delivered. Then we look into the case where we have the cellular network infrastructure, but it is being pressured due to rapid increase in volume of network traffic (as seen during a major event) or it has been replaced by low capacity mobile tower. In this case we look at offloading as much traffic as possible from the infrastructure to device-to-device communication. However, the host-oriented model of the TCP/IP-based Internet poses challenges to this communication pattern. A scheme that uses an ICN model to fetch content from nearby peers, increases the resiliency of the network in cases of outages and disasters. We collected content popularity statistics from social media to create a content request pattern and evaluate our approach through the simulation of realistic urban scenarios. Additionally, we analyze the scenario of large crowds in sports venues. Our simulation results show that we can offload traffic from the backhaul network by up to 51.7\%, suggesting an advantageous path to support the surge in traffic while keeping complexity and cost for the network operator at manageable levels. Finally, we look at adaptive bit-rate streaming (ABR) streaming, which has contributed significantly to the reduction of video playout stalling, mainly in highly variable bandwidth conditions. ABR clients continue to suffer from the variation of bit rate qualities over the duration of a streaming session. Similar to stalling, these variations in bit rate quality have a negative impact on the users’ Quality of Experience (QoE). We use a trace from a large-scale CDN to show that such quality changes occur in a significant amount of streaming sessions and investigate an ABR video segment retransmission approach to reduce the number of such quality changes. As the new HTTP/2 standard is becoming increasingly popular, we also see an increase in the usage of HTTP/2 as an alternative protocol for the transmission of web traffic including video streaming. Using various network conditions, we conduct a systematic comparison of existing transport layer approaches for HTTP/2 that is best suited for ABR segment retransmissions. Since it is well known that both protocols provide a series of improvements over HTTP/1.1, we perform experiments both in controlled environments and over transcontinental links in the Internet and find that these benefits also “trickle up” into the application layer when it comes to ABR video streaming where HTTP/2 retransmissions can significantly improve the average quality bitrate while simultaneously minimizing bit rate variations over the duration of a streaming session. Taking inspiration from the first two approaches, we take into account the resiliency of a multi-path approach and further look at a multi-path and multi-stream approach to ABR streaming and demonstrate that losses on one path have very little impact on the other from the same multi-path connection and this increases throughput and resiliency of communication.
164

Srovnání norského a skotského přístupu k hrozbě organizovaného zločinu v globalizovaném světě / A comparative study of Norway and Scotland's effort to address and counter the threat of organized crime in a globalized world

Ramberg, Marte Skaatan January 2021 (has links)
A comparative study of Norway and Scotland's effort to address and counter the threat of organized crime in a globalized world. Marte Skaatan Ramberg The concept of organized crime is a rather "fussy", with over two hundred definitions to its name. This master thesis aims to debate the concept of organized crime and utilizing the concept for an investigating look at Norway and Scotland`s effort to cut and combat the effect of organized crime. Whilst tackling the ambiguity of organized crime the thesis also share some light on the security aspect of organized crime for the state and for the individual, using the framework of human security and traditional state-centric approach when evaluating the impact of organized crime. Different polices and laws shared between Norway and Scotland along with their objectives is also discussed all centered around the research questions - How does Norway approach and counter the threat of organized crime compared to Scotland? - What are the successes and failures with these strategies?
165

MINUSMA a příklon OSN k proti-povstaleckým a proti-teroristickým operacím / MINUSMA and the United Nation's Turn to Counter-terrorism and Counter-insurgency

van Oppen Ardanaz, Gabriel January 2019 (has links)
This Master's thesis will focus on the newest trends in the field of United Nations (UN) peacekeeping operations that are moving the organization to unknown territory by deploying in theatres where missions are faced with asymmetric threats. In this regard, the United Nations Multidimensional Integrated Stabilization Mission in Mali (MINUSMA), constituted as a groundbreaking and innovative peacekeeping operation, is spearheading a realignment in peacekeeping that can potentially shape future operations to come, as mandates increasingly reflect roles in areas such as counter-insurgency and counter-terrorism. The core objective of this study will be to analyze why MINUSMA is being forced to go green while studying how it is doing so, reflecting on past experiences from other operations such as the International Stabilization Assistance Force (ISAF) in Afghanistan and the Multi-National Force in Iraq (MNF-I), that have guided changes in MINUSMA's doctrines and capabilities. Gabriel van Oppen Ardanaz
166

Retaining Organizational Agility : How to Stay Competitive Without Competing

Karlstedt, Jens, Hellenborg, Sebastian January 2020 (has links)
While conventional approaches of managing organizations have been considered to be outdated, Organizational Agility has been acclaimed for its prowess to cope with today's increasingly volatile and dynamic environment. Yet the predominant focus has been directed towards how agility is achieved, while its retention as organizations grow has to a great extent been unexplored. Through a qualitative case study of a renowned organization for its unorthodox approach, this study aims to contribute with an extension to the current scope of organizational agility by stretching beyond the focus on mere transformations in an attempt to understand in what ways organizational agility is retained as they grow. The findings of this study challenge the common conceptions found within literature suggesting that changes in the external environment are what drives organization’s to be agile in order to sustain its competitiveness. Organizational agility has thus primarily been considered to be constituted by dynamic adaptations in accordance to forces of the external environment. In contrast, this study finds that the retention of organizational agility during growth is an evolutionary process that is internally driven by placing indispensable value on the employees and by focusing on the organization itself, its desire and community. Retaining organizational agility is thus something that grows “from the inside and out”.
167

En framtida resurs eller ett arv från det förflutna? : en teoriprövande enfallsstudie om nätverksbaserat försvar i Irak

Samor, Adam January 2020 (has links)
The theory of network centric warfare has since its introduction in the early 2000s experienced both a substantial hype and spectacular collapse. Various studies have focused on the theory’s ability to increase mission effectiveness, predominantly within sea and air operations, whilst the domain of land warfare remains largely uncharted. This single case study assesses the theory’s ability to deliver mission effectiveness in ground combat. The case chosen for the study was the U.S. army 3rd Infantry Division and their offensive during the invasion of Iraq 2003. It is concluded that, while a digitalized force, the interoperability within the division was low, effectively excluding definite claims of network centric warfare’s ability to produce mission effectiveness in the land warfare domain. Being one of a few studies on this complex domain, these results warrant for further research. In addition to its findings the study provides an additional tool for how the effects and workings of network centric warfare may be understood and studied in the future.
168

Efficient naming for Smart Home devices in Information Centric Networks

Rossland Lindvall, Caspar, Söderberg, Mikael January 2020 (has links)
The current network trends point towards a significant discrepancy between the data usage and the underlying architecture; a severely increasing amount of data is being sent from more devices while data usage is becoming more data-centric instead of the previously host-centric. Information Centric Network (ICN) is a new alternative network paradigm that is designed for a data-centric usage. ICN is based on uniquely naming data packages and making it location independent. This thesis researched how to implement an efficient naming for ICN in a Smart Home Scenario. The results are based on testing how the forwarding information base is populated for numerous different scenarios and how a node's duty cycle affects its power usage. The results indicate that a hierarchical naming is optimized for hierarchical-like network topology and a flat naming for interconnected network topologies. An optimized duty cycle is strongly dependent on the specific network and accordingto the results can a sub-optimal duty cycle lead to excessive powerusage.
169

Au-delà des frontières entre langages de programmation et bases de données / Breaking boundaries between programming languages and databases

Lopez, Julien 13 September 2019 (has links)
Plusieurs classes de solutions permettent d'exprimer des requêtes dans des langages de programmation: les interfaces spécifiques telles que JDBC, les mappings objet-relationnel ou object-relational mapping en anglais (ORMs) comme Hibernate, et les frameworks de requêtes intégrées au langage comme le framework LINQ de Microsoft. Cependant, la plupart de ces solutions ne permet de requêtes visant plusieurs bases de données en même temps, et aucune ne permet l'utilisation de logique d'application complexe dans des requêtes aux bases de données. Dans cette thèse, nous détaillons la création d'un framework de requêtes intégrées au langage nommé BOLDR qui permet d'évaluer dans les bases de données des requêtes écrites dans des langages de programmation généralistes qui contiennent de la logique d'application, et qui ciblent différentes bases de données potentiellement basées sur des modèles de données différents. Dans ce framework, les requêtes d'une application sont traduites vers une représentation intermédiaire de requêtes, puis réécrites pour éviter le phénomène "d'avalanche de requêtes" et pour profiter au maximum des capacités d'optimisation des bases de données, et enfin envoyées pour évaluation vers les bases de données ciblées et les résultats obtenus sont convertis dans le langage de programmation de l'application. Nos expériences montrent que les techniques implémentées dans ce framework sont applicables pour de véritables applications centrées données, et permettent de gérer efficacement un vaste champ de requêtes intégrées à des langages de programmation généralistes. / Several classes of solutions allow programming languages to express queries: Specific APIs such as JDBC, Object-Relational Mappings (ORMs) such as Hibernate, and language-integrated query frameworks such as Microsoft's LINQ. However, most of these solutions do not allow for efficient cross-databases queries, and none allow the use of complex application logic from the programming language in queries. In this thesis, we create a language-integrated query framework called BOLDR that, in particular, allows the evaluation in databases of queries written in general-purpose programming languages that contain application logic, and that target different databases of possibly different data models. In this framework, application queries are translated to an intermediate representation, then rewritten in order to avoid query avalanches and make the most out of database optimizations, and finally sent for evaluation to the corresponding databases and the results are converted back to the application. Our experiments show that the techniques we implemented are applicable to real-world database applications, successfully handling a variety of language-integrated queries with good performances.
170

Supervision en transport multimodal / Supervision in Multi-Modal Transportation System

Theissing, Simon 05 December 2016 (has links)
Les réseaux de transport multimodaux modernes sont essentiels pour la durabilité écologique et l’aisance économique des agglomérations urbaines, par conséquent aussi pour la qualité de vie de leurs habitants. D’ailleurs, le bon fonctionnement sur le plan de la compatibilité entre les différents services et lignes est essentiel pour leur acceptation, étant donné que (i) la plupart des trajets nécessitent des changements entre les lignes et que (ii) des investissements coûteux, dans le but de créer des liens plus directs avec la construction de nouvelles lignes ou l’extension de lignes existantes, ne sont pas à débattre. Une meilleure compréhension des interactions entre les modes et les lignes dans le contexte des transferts de passagers est ainsi d’une importance cruciale. Toutefois, comprendre ces transferts est singulièrement difficile dans le cas de situations inhabituelles comme des incidents de passagers et/ou si la demande dévie des plans statistiques à long terme. Ici le développement et l’intégration de modèles mathématiques sophistiqués peuvent remédier à ces inconvénients. À ce propos, la supervision via des modèles prévoyants représente un champ d’application très prometteur, analysée ici. La supervision selon des modèles prévoyants peut prendre différentes formes. Dans le présent travail, nous nous intéressons à l’analyse de l’impact basé sur des modèles de différentes actions, comme des départs en retard de certains véhicules après un arrêt, appliqué sur le fonctionnement du réseau de transport et sa gestion de situations de stress qui ne font pas partie des données statistiques. C’est pourquoi nous introduisons un nouveau modèle, un automate hybride avec une dynamique probabiliste, et nous montrons comment ce modèle profondément mathématique peut prédire le nombre de passagers dans et l’état de fonctionnement du véhicule en question du réseau de transport, d’abord par de simples estimations du nombre de tous les passagers et la connaissance exacte de l’état du véhicule au moment de l’incident. Ce nouvel automate réunit sous un même regard les passagers demandeurs de services de transport à parcours fixes ainsi que les véhicules capables de les assurer. Il prend en compte la capacité maximale et le fait que les passagers n’empruntent pas nécessairement des chemins efficaces, dont la représentation sous la forme d’une fonction de coût facilement compréhensible devient nécessaire. Chaque passager possède son propre profil de voyage qui définit un chemin fixe dans l’infrastructure du réseau de transport, et une préférence pour les différents services de transport sur son chemin. Les mouvements de véhicules sont inclus dans la dynamique du modèle, ce qui est essentiel pour l’analyse de l’impact de chaque action liée aux mouvements de véhicule. De surcroît, notre modèle prend en compte l’incertitude qui résulte du nombre inconnu de passagers au début et de passagers arrivant au fur et à mesure. Comparé aux modèles classiques d’automates hybrides, notre approche inspirée du style des réseaux de Pétri ne requiert pas le calcul de ces équations différentielles à la main. Ces systèmes peuvent être dérivés de la représentation essentiellement graphique d’une manière automatique pour le calcul en temps discret d’une prévision. Cette propriété de notre modèle réduit le risque de précisions faites par des humains et les erreurs qui en résulteraient. Après avoir introduit notre nouveau modèle, nous développons dans ce rapport également quelques éléments constitutifs sous la forme d'algorithmes qui visent les deux types d'impasses qui sont probables d'occurir pendant la simulation faisant un pronostic, c-à-d l'intégration numérique des systèmes de haute dimension d'équations différentielles et l'explosion combinatoire de son état discret. En plus, nous prouvons la faisabilité des calculs et nous montrons les bénéfices prospectifs de notre approche dans la forme de quelques tests simplistes et quelques cas plus réalistes. / Without any doubt, modern multimodal transportation systems are vital to the ecological sustainability and the economic prosperity of urban agglomerations, and in doing so to the quality of life of their many inhabitants. Moreover it is known that a well-functioning interoperability of the different modes and lines in such networked systems is key to their acceptance given the fact that (i) many if not most trips between different origin/destination pairs require transfers, and (ii) costly infrastructure investments targeting the creation of more direct links through the construction of new or the extension of existing lines are not open to debate. Thus, a better understanding of how the different modes and lines in these systems interact through passenger transfers is of utmost importance. However, acquiring this understanding is particularly tricky in degraded situations where some or all transportation services cannot be provided as planned due to e.g. some passenger incident, and/or where the demand for these scheduled services deviates from any statistical long term-plannings. Here, the development for and integration of sophisticated mathematical models into the operation of such systems may provide remedy, where model-predictive supervision seems to be one very promising area of application which we consider here. Model-predictive supervision can take several forms. In this work, we focus on the model-based impact analysis of different actions, such as the delayed departure of some vehicle from a stop, applied to the operation of the considered transportation system upon some downgrading situation occurs which lacks statistical data. For this purpose, we introduce a new stochastic hybrid automaton model, and show how this mathematically profound model can be used to forecast the passenger numbers in and the vehicle operational state of this transportation system starting from estimations of all passenger numbers and an exact knowledge of the vehicle operational state at the time of the incident occurrence. Our new automaton model brings under the same roof, all passengers who demand fixed-route transportation services, and all vehicles which provide them. It explicitly accounts for all capacity-limits and the fact that passengers do not necessarily follow efficient paths which must be mapped to some simple to understand cost function. Instead, every passenger has a trip profile which defines a fixed route in the infrastructure of the transportation system, and a preference for the different transportation services along this route. Moreover, our model does not abstract away from all vehicle movements but explicitly includes them in its dynamics, which latter property is crucial to the impact analysis of any vehicle movement-related action. In addition our model accounts for uncertainty; resulting from unknown initial passenger numbers and unknown passenger arrival flows. Compared to classical modelling approaches for hybrid automata, our Petri net-styled approach does not require the end user to specify our model's many differential equations systems by hand. Instead, all these systems can be derived from the model's predominantly graphical specification in a fully automated manner for the discrete time computation of any forecast. This latter property of our model in turn reduces the risk of man-made specification and thus forecasting errors. Besides introducing our new model, we also develop in this report some algorithmic bricks which target two major bottlenecks which are likely to occur during its forecast-producing simulation, namely the numerical integration of the many high-dimensional systems of stochastic differential equations and the combinatorial explosion of its discrete state. Moreover, we proof the computational feasibility and show the prospective benefits of our approach in form of some simplistic test- and some more realistic use case.

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