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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.
51

Vliv zatížení centrálního serveru na IMS síť / Central server load impact on the IMS network

Kňazovický, Pavel January 2011 (has links)
This master’s thesis deals with architecture of the IMS network and analysis of the affects when loading the network. Architecture of IMS is a network of new generation. It convergates fixed and mobile networks and it enables quick installation of new multimedia services. The first chapter is focused on the description of the IMS architecture, its components and their function. The next chapter is devoted to the main protocols in the IMS system. It is mainly about signalization protocol SIP. The third chapter focuses on the queueing theory. For simulation of the IMS network, Open IMS Core enviroment was chosen, described in the fourth chapter. Next chapter is dedicated to the IMS Bench SIPp tool used for generating and testing the SIP protocol with focus on the IMS. The final chapter dedicates to the realization of an IMS network. The begining of this chapter deals with the description of individual conections generated by the IMS Bench SIPp tool. In the next part load tests focused on the created IMS network are created and analyzed in detail. The end of the chapter describes the implementation of the real finished call between devices and the Android operating system.
52

Diameter service creation investigation and HSS evaluation

Lindgren, Petter January 2010 (has links)
With a prospect of creating a new generation of cellular networks using IP based communication, service providers, operators and developers have created the IP Multimedia Subsystem (IMS). Which with a more open architecture than older cellular networks will make it more like the internet in terms of service creation. This thesis creates an example service that uses subscriber data in the Home Subscriber Server (HSS) to deliver a service to the network’s users. The service is created to extend the functionality of the IMS test environment at Attentec AB to assist them in their efforts of learning and experimenting with the IMS core network. In this thesis the FoHSS used in the test environment is evaluated in order to measure its performance. This thesis gives examples of the implementation overhead of creating services in the IMS network and shows some of the functionality that is available to IMS services compared to service creation on the internet. Load tests of the FoHSS are made and shows that it uses polling to maintain subscription updates and that it has a negative impact on performance under heavy load. This thesis suggests that it is good for IMS test environments but not commercial use. / Med ambitionen att skapa nästa generations mobilnätverk med IP-baserad kommunikation, har tjänsteleverantörer, operatörer och utvecklare skapat IMS. IMS som med en mer öppen arkitektur än dess föregångare försöker närma sig internet när det gäller skapande av nya tjänster. Det ska vara enklare och ta mindre tid än i ett äldre mobilnät. Detta examensarbete skapar en exempeltjänst som använder användaruppgifter i IMS användardatabas för att leverera en tjänst till nätets användare. Tjänsten har skapats för att utöka funktionerna i den IMS testmiljö som Attentec AB har satt upp för att underlätta för sina anställda att lära sig mer om med IMS-kärnan genom att experimentera med den. I denna avhandling utvärderas även den HSS som finns i testmiljön. Examensarbetet ger exempel på det extraarbete som behöver göras för att skapa tjänster i ett IMS-nätverk och visar på en del av den funktionalitet som finns tillgänglig för tjänster i IMS jämfört med skapande av nya tjänster på Internet. De lasttester som utfördes på användardatabasen visar att den använder pollning för att upptäcka ändringar i användardata och skicka ut uppdateringar till prenumeranter samt att dessa har en negativ inverkan på prestandan under tung belastning. Denna avhandling visar att den passar bra i IMS testmiljöer men för inte kommersiellt bruk.
53

IMS Interworking

Kalaglarski, Boris Iv., Di Geronimo, Emilio January 2007 (has links)
The goal of this project was to analyze the IP Multimedia Subsystem (IMS) with respect to the interworking functionality between two or more IMS domains belonging to different operators. The thesis presents an overview of IMS, its purpose, the circumstances and the environment in which it has evolved, and a look into some of the challenges that lie ahead. Through careful examination of the history of the mobile communications and of IMS itself, the thesis attempts to give the reader a full and comprehendible understanding of what IMS is, what its purpose is, and why it came into existence. The thesis considers the different models of IMS interworking, as they are currently envisioned by the standardisation bodies and the telecom industry. This analysis aims to identify some of the problematic aspects of the IMS Interworking and to suggest concrete areas for further investigation, which will contribute to the future successful IMS development and deployment. The report looks into such aspects of IMS interworking as the DNS, different models for ENUM DNS resolution; security issues and technical challenges of security with respect to the network as a whole and some of the IMS network elements in particular, such as the DNS. This thesis also presents the findings of the authors, regarding the challenges of interworking between networks built to support different versions of the IP protocol. The thesis focuses on the areas of interest, mentioned above, as these have been identified as being of particular significance in connection with the further development of the IMS architecture. / Målet med denna uppsats var att analysera IP Multimedia Subsystem (IMS) med fokus på samverkan mellan två eller flera IMS domäner som tillhör olika operatörer. Examensjobbet beskriver en övergripande bild av IMS, dess målsättning, förhållanderna och miljön som den har utvecklats i och några utav utmaningarna som ligger framöver. Uppsatsen försöker med hjälp av bakgrundsfakta om mobiltelefonins historia ge läsarna förståelse om vad IMS är, syftet med det och varför det existerar. Uppsatsen beskriver olika samverkningsmodeller av IMS som grundar sig i modeller från de olika standardiseringsorganen samt från telecomindustrin. Målet med denna analys är att identifiera några problemaspekter samt presentera konkreta områden att fortsätta arbeta på gällande IMS och dess gällande samverkan mellan olika operatörer. Detta kan bidra till fortsatt framgång med utvecklingen samt utspridningen av IMS. Uppsatsen tar upp samverkningsproblem med IMS så som DNS, olika uppslagsmetoder av ENUM DNS, säkerhetsfrågor och säkerhetstekniska utmaningar med fokus på nätverket samt några IMS nätverkselement som DNS:en. Uppsatsen lägger också fram författarnas slutsatser gällande samverkan av de olika nätverken med olika versioner av IP protokollet. Examensjobbet fokuserar på de olika områderna som är ovan nämnda, då de har blivit identiferade med speciell betydelse för att kunna fortsätta att framgångsrikt utveckla IMS arkitekturen.
54

Min dröm är att ta studenten : En studie om svenska språkets påverkan på unga kvinnors gymnasieval / My dream is to graduate : A study about the influence of the swedish language in young womens high-school application

Frisell, Gabriel, Muco, Erteine January 2023 (has links)
Ett val är aldrig helt fritt från påverkansfaktorer. Ibland är de medvetna och ibland omedvetna. I denna studie har vi undersökt hur inlärningen av det svenska språket påverkar kvinnliga elever som går språkintroduktion i deras gymnasieval samt deras syn på detta. För att få reda på svaren har vi använt oss av en kvalitativ forskningsmetod baserat på semistrukturerade intervjuer.  Vi har genomfört enskilda intervjuer och en fokusintervju med sex unga kvinnor mellan 16-19 år. Alla intervjupersoner går på introduktionsprogrammet med inriktningen språkintroduktion (IMS) och har under våren 2023 sökt till ett nationellt gymnasieprogram. Med hjälp av teorierna Careership och Social Cognitive Career Theory har vi analyserat resultatet som visar på att unga kvinnor kan påverkas av hur deras syn är på sina kunskaper i det svenska språket. När de söker ett gymnasieprogram tar de alla språket i beaktning. Ibland är det i form av en medveten strategi där de ibland kompromissar sitt val och ibland mindre medvetet i form av att utöver drömutbildningen söka program som de tror de kommer in på. Svenska språkets påverkan utöver det som sker under inlärningen märks även i ett socialt fält där intervjupersonernas upplevelse är att de inte får chansen att lära sig språket bland de som pratar svenska som modersmål. Detta för att de har blivit exkluderade från skolgemenskapen och satt i ett eget sammanhang i form av IMS vilket också är något som påverkat deras valmöjligheter i praktiken.
55

Ion Structure Characterization and Energetics in the Gas Phase Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry and Ion Mobility Spectrometry

Heravi, Tina 08 August 2022 (has links)
In this dissertation, I used Fourier transform ion cyclotron resonance mass spectrometry (FTICR) and ion mobility spectrometry (IMS) to study the structure and energetics of supramolecular complex ions in the gas phase. Using the CRAFTI (cross sectional areas by Fourier transform ion cyclotron resonance) technique developed by Dearden’s lab we observed that complexes with alkali cations capping the portals of cucurbit[5]uril (CB[5]) bind halide anions size-selectively in the gas phase. Our data suggest that Cl– binds inside the CB[5] cavity, Br– binds both inside (with Na+ions capping the portals of CB[5]) and outside (when K+caps CB[5]), and I– binds weakly outside. Although geometry optimization at the M06-2X/6-31+G* level of ab initio theory suggests internal anion binding is energetically favored over external binding, we believe the externally-bound complexes observed experimentally must be due to large energetic barriers hindering the passing of large anions through the CB[5] portal, preventing access to the interior. Calculation of the barriers to anion egress using MMFF//M06-2X/6-31+G* theory supports this idea. Collision cross section (CCS) measurements using the CRAFTI method for CB[5] complexes with various alkali metals and different neutral guests (methanol, ethanol, formic acid, and acetonitrile) along with the results of mass spectra from FTICR show that both the sizes and the resulting charge densities of the alkali metal ions affect the relative tendency of the guests to bind inside CB[5]. The CCS values suggest that methanol, formic acid, and acetonitrile are internally bound CB[5] while ethanol is bound outside the CB[5] host. The relative abundances of the paired peaks in the obtained mass spectra indicate that the inclusion of formic acid and methanol are enhanced when K+ ions cap the complexes, whereas the inclusion of acetonitrile is enhanced when Cs+ ions cap the complexes. The relative abundance of ethanol complexes increases when Na+ ions cap the complexes. CRAFTI CCS values for singly- and doubly-charged cucurbit[n]uril (n = 5, 6, and 7), decamethylcucurbit[5]uril (mc5), and cyclohexanocucurbit[5]uril (CB*[5]) complexes of alkali metal cations (Li+-Cs+) show +2 complex ions have CCS values ranging between 94-105% of those of their +1 counterparts (increasing with metal ion size). These results are consistent with CCS values were calculated using the projection approximation (PA). Ion mobility measurements of the same complexes find the CCS of +2 complexes to be in all cases 9-12% larger than those of the corresponding +1 complexes, with little metal ion dependence. Trajectory method (TM) calculations of CCS for the same structures consistently yield values 7-10% larger for the +2 complexes than for the corresponding +1 complexes and little metal ion dependence which agrees with experimental values.
56

Forensic Applications of Gas Chromatography-Differential Mobility Spectrometry, Gas Chromatography/Mass Spectrometry, and Ion Mobility Spectrometry with Chemometric Analysis

Lu, Yao 16 April 2010 (has links)
No description available.
57

Analýza řídicích procedur v mobilních sítích EPS / Analysis of control procedures in EPS networks

Zagumennov, Egor January 2016 (has links)
The aim of this thesis is acquaintance with the EPS system of LTE and IMS subsystem. The thesis is aimed on analysis of the control procedures related to operations between the terminal and the packet core network of the fourth generation such as logging into the system, user authentication, change the viewing area, handover and disconnection from the network.
58

Performance Evaluation and Elastic Scaling of an IP Multimedia Subsystem Implemented in a Cloud

Umair, Muhammad January 2013 (has links)
Network (NGN) technology which enables telecommunication operators to provide multimedia services over fixed and mobile networks. All of the IMS infrastructure protocols work over IP which makes IMS easy to deploy on a cloud platform. The purpose of this thesis is to analysis a novel technique of “cloudifying” the OpenIMS core infrastructure. The primary goal of running OpenIMS in the cloud is to enable a highly available and horizontally scalable Home Subscriber Server (HSS). The resulting database should offer high availability, and high scalability. The prototype developed in this thesis project demonstrates a virtualized OpenIMS core with an integrated horizontal scalable HSS. Functional and performance measurements of the system under test (i.e. the virtualized OpenIMS core with horizontally scalable HSS) were conducted. The results of this testing include an analysis of benchmarking scenarios, the CPU utilization, and the available memory of the virtual machines. Based on these results we conclude that it is both feasible and desirable to deploy the OpenIMS core in a cloud. / IP Multimedia Subsystem (IMS) ramverk är ett Next Generation Network (NGN) teknik som möjliggör teleoperatörer att erbjuda multimediatjänster via fasta och mobila nät. Alla IMS infrastruktur protokollen fungera över IP som gör IMS lätt att distribuera på ett moln plattform. Syftet med denna uppsats är att analysera en ny teknik för “cloudifying” den OpenIMS kärninfrastrukturen.  Det primära målet med att köra OpenIMS i molnet är att möjliggöra en hög tillgänglighet och horisontellt skalbara Server Home Subscriber (HSS). Den resulterande databasen bör erbjuda hög tillgänglighet och hög skalbarhet. Prototypen utvecklas i detta examensarbete visar en virtualiserad OpenIMS kärna med en integrerad horisontell skalbar HSS. Funktionella och prestanda mätningar av systemet under test (dvs. virtualiserade OpenIMS kärnan med horisontellt skalbara HSS) genomfördes. Resultaten av detta test inkluderar en analys av benchmarking scenarier, CPU-användning, och tillgängligt minne för de virtuella maskinerna. Baserat på dessa resultat drar vi slutsatsen att det är både möjligt och önskvärt att distribuera OpenIMS kärnan i ett moln.
59

Service composition in converged service environment / Composition de service dans un environnement de service convergé

Huang, Cuiting 02 May 2012 (has links)
L'objectif de cette thèse est de fournir des mécanismes améliorés pour déployer des services compétitifs par des manières rapides et rentables. Nous proposons un modèle de composition de service basé sur un environnement IMS/Web convergent. Ce modèle permet aux utilisateurs non professionnels de réutiliser les services existants pour créer de nouveaux services facilement. Pour améliorer la fonctionnalité de composition automatique, trois stratégies, y compris mise à jour passive, mise à jour active et mise à jour hybride sont proposées et analysées. Nous introduisons ensuite une plateforme centralisée d'exposition de service pour une variété de services, y compris services de Télécom / Web / appareil / services générés par les utilisateurs. Cette plateforme vise à renforcer les caractéristiques de centrée-sur-utilisateur et convergence, et fournir l'accès unifié à différents services. Par la suite, deux modèles basés sur le P2P sont conçus pour compléter le modèle centralisé: i) Un modèle hiérarchique basé sur Chord pour garantir l'efficacité de la découverte de services. Il adopte le concept de publication et découverte de service abstrait pour permettre à la recherche de service ambiguë. ii) Un modèle de superposition-triplex et P2P basé, qui cible principalement des services offerts par les appareils. Dans ce modèle, nous utilisons des passerelles pour déléguer des appareils résidant en eux pour l'exposition globale de services, et utilisons une architecture basée sur une superposition triplex, qui comprend une couche P2P non structurée, une couche de réseau sémantique (SON), et une couche de dépendance de service, pour la partage de l'information de service et la découverte de services / The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery
60

Razvoj modela internih kontrolnih mehanizama u funkciji upravljanja preduzećem / Development of the Models of Internal Control Mechanisms for the Purpose of Company Management

Živkov Emil 16 July 2015 (has links)
<p>Kvalitetna postavka kombinacije internih kontrolnih mehanizama, u značajnoj meri oredeljuje i kvalitet samog kontrolnog okruženja preduzeća. Ovim istraživanjem je potvrđena činjenica da kvalitetno kontrolno okruženje značajno doprinosi dobrom upravljanju ciljevima i rizicima. Centralno mesto u procesu korporativnog upravljanja zauzimaju interni kontrolni mehanizmi koncentrisani u procesu upravljanja rizicima. Interni kontrolni mehanizmi upotrebom svojih kontrolnih &bdquo;alata&ldquo;, olakšavaju procenu rizika, njegovo prepoznavanje i merenje. Svako iz svog ugla: računovodstvo, kontroling, Fast Close, ERP (Enterprise Resource Planning ), IMS (Integrisani sistemi menadžmenta) , finansijsko upravljanje i kontrola, ERM (Enterprise Risk Management) i interna revizija, su značajni elementi internih kontrolnih mehanizama, u procesu</p> / <p>Creating a right combination of internal control mechanisms, to a large extent, also determines the quality of a company&rsquo;s control environment. This research has confirmedthe fact that an efficient control environment significantly contributes to proper management of goals and risks. The central place in the process of corporate governance belongs to internal control mechanisms centered in the process of risk management. Internal control mechanisms, by using their control &quot;tools&quot;, facilitate the risk assessment, its identification and measurement. Everyone from their own perspective: accounting, controlling, Fast Close, ERP (Enterprise Resource Planning), IMS (Integrated Management Systems), financial management and control, ERM (Enterprise Risk Management) and internal audit, are important elements of internal control mechanisms in the process of managing the key financial and operational risks.</p>

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