Bakgrund: Akutsjukvårdens syfte är att tillgodose personer som drabbats av akut skada eller sjukdom en god och säker vård genom hela den akuta vårdkedjan. Brister inom hälso- och sjukvården leder årligen till att patienter skadas. Förutom stort lidande hos patienter och anhöriga belastar detta ett redan hårt pressat vårdsystem. I vårdövergångarna kan misstag eller missförstånd ske som gör att information som ges tolkas olika eller helt går förlorad. För att kunna arbeta förebyggande och minimera antalet vårdskador för patienterna måste risker samt vart dessa uppstår synliggöras. Syfte: Syftet var att belysa patientsäkerhetsrisker vid patientens övergång från ambulanssjukvård till akutmottagning. Metod: En litteraturöversikt med en systematiskt ansats där 15 vetenskapliga artiklar användes. Artiklarna kvalitetsgranskades innan inkludering för att säkerställa ett resultat av god kvalitét. Resultatet sammanställdes genom en integrerad analys. Resultat: Det framkom patientsäkerhetsrisker kopplades till brister i organisationen och bristande förvaltande av vårdrelationen. Organisatoriska brister var förlust av information om patientens tillstånd, bristande fokus på patienten och dennes omvårdnadsbehov. Avsaknad av tydlighet kring vem som bar ansvaret för patienten och dennes vård i vårdövergången samt risker för patienten kopplade till personalens kompetens. Bristande förvaltande av vårdrelationen manifesteras genom avsaknad av samsyn kring patientens situation och sjukdomsförlopp samt bristande bemötande gentemot patienter som ofta besökte akutmottagningen och/eller var i behov av ambulans. Slutsats: För att kunna säkerställa en patientsäker vård förutsätter det att det finns organisatoriska förutsättningar samt att patienten sätts i fokus. Idag ses flera patientsäkerhetsrisker och det behöver ske en förändring i akutsjukvårdens organisation och förhållningssätt för att kunna säkra en god vård för patienten. / Background: The purpose of emergency healthcare is providing people who have suffered an acute injury or illness a good and safe care throughout the emergency care chain. Deficiencies in healthcare lead to patients being injured annually. In addition to suffering patients and relatives, this burdens an already hard-pressed healthcare system. In care transitions, mistakes or misunderstandings can occur, which means information given is interpreted differently or is lost. To be able to work preventively and minimize the number of care injuries for patients, risks and where they occur must be made visible. Aim: The aim was to highlight patient safety risks during the patients transfer from ambulance care to the emergency department. Method: A literary review using a systematic approach including 15 research articles was used. The articles were quality checked before being included to secure a result with a good quality. The result was concluded through an integrated analysis. Results: Patient safety risks were identified linked to deficiencies in the organization and lack of management of the care relationship. Organizational deficiencies were lost of information about the patient’s condition, lack of focus on the patient and their care needs. Lack of clarity of who was responsible for the patient and patients care during the care transition and risks for the patient linked to staff competence. Lack of management of the care relationship manifested through lack of consensus for the patient’s situation and course of disease and lack of treatment toward patients that often visited the emergency department and/or needed an ambulance. Conclusion: To ensure patient safety, there needs to be organizational prerequisites and focus on the patient. Today, major patient safety risks are seen and there needs to be a change in the organization and the approach of emergency healthcare to ensure good care for the patient.

Over recent years, wireless communication systems have been experiencing a dramatic and continuous growth in the number of subscribers, thus placing extra demands on system capacity. At the same time, keeping Quality of Service (QoS) at an acceptable level is a critical concern and a challenge to the wireless network designer. In this sense, performance analysis must be the first step in designing or improving a network. Thus, powerful mathematical tools for analysing most of the performance metrics in the network are required. A good modelling and analysis of the wireless cellular networks will lead to a high level of QoS. In this thesis, different analytical models of various handoff schemes and resource re-allocation in homogeneous and heterogeneous wireless cellular networks are developed and investigated. The sustained increase in users and the request for advanced services are some of the key motivations for considering the designing of Hierarchical Cellular Networks (HCN). In this type of system, calls can be blocked in a microcell flow over to an overlay macrocell. Microcells in the HCN can be replaced by WLANs as this can provide high bandwidth and its users have limited mobility features. Efficient sharing of resources between wireless cellular networks and WLANs will improve the capacity as well as QoS metrics. This thesis first presents an analytical model for priority handoff mechanisms, where new calls and handoff calls are captured by two different traffic arrival processes, respectively. Using this analytical model, the optimised number of channels assigned to II handover calls, with the aim of minimising the drop probability under given network scenarios, has been investigated. Also, an analytical model of a network containing two cells has been developed to measure the different performance parameters for each of the cells in the network, as well as altogether as one network system. Secondly, a new solution is proposed to manage the bandwidth and re-allocate it in a proper way to maintain the QoS for all types of calls. Thirdly, performance models for microcells and macrocells in hierarchical cellular networks have been developed by using a combination of different handoff schemes. Finally, the microcell in HCN is replaced by WLANs and a prioritised vertical handoff scheme in an integrated UMTS/WLAN network has been developed. Simulation experiments have been conducted to validate the accuracy of these analytical models. The models have then been used to investigate the performance of the networks under different scenarios.

A finales de los años noventa, y al comienzo del nuevo milenio, las redes inalámbricas han evolucionado bastante, pasando de ser sólo una tecnología prometedora para convertirse en un requisito para las actividades cotidianas en las sociedades desarrolladas. La infraestructura de transporte también ha evolucionado, ofreciendo comunicación a bordo para mejorar la seguridad vial y el acceso a contenidos de información y entretenimiento. Los requisitos de los usuarios finales se han hecho dependientes de la tecnología, lo que significa que sus necesidades de conectividad han aumentado debido a los diversos requisitos de las aplicaciones que se ejecutan en sus dispositivos móviles, tales como tabletas, teléfonos inteligentes, ordenadores portátiles o incluso ordenadores de abordo (On-Board Units (OBUs)) dentro de los vehículos. Para cumplir con dichos requisitos de conectividad, y teniendo en cuenta las diferentes redes inalámbricas disponibles, es necesario adoptar técnicas de Vertical Handover (VHO) para cambiar de red de forma transparente y sin necesidad de intervención del usuario. El objetivo de esta tesis es desarrollar algoritmos de decisión (Vertical Handover Decision Algorithms (VHDAs)) eficientes y escalables, optimizados para el contexto de las redes vehiculares. En ese sentido se ha propuesto, desarrollado y probado diferentes algoritmos de decisión basados en la infraestructura disponible en las actuales, y probablemente en las futuras, redes inalámbricas y redes vehiculares. Para ello se han combinado diferentes técnicas, métodos computacionales y modelos matemáticos, con el fin de garantizar una conectividad apropiada, y realizando el handover hacia las redes más adecuadas de manera a cumplir tanto con los requisitos de los usuarios como los requisitos de las aplicaciones. Con el fin de evaluar el contexto, se han utilizado diferentes herramientas para obtener información variada, como la disponibilidad de la red, el estado de la red, la geolocalización / Márquez Barja, JM. (2012). SCALABLE AND EFFICIENT VERTICAL HANDOVER DECISION ALGORITHMS IN VEHICULAR NETWORK CONTEXTS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17869

Cette thèse a été motivée par le nouveau contexte ubiquitaire des réseaux ambiants sans-fil. Les protocoles Internet ont été conçus il y a 30 ans sans prendre en considération l'usage nomade des réseaux et ne répondent pas aux nouvelles contraintes de la mobilité. Notre but a été de concevoir des mécanismes pour rendre la mobilité transparente aux applications et utilisateurs. Une partie de notre travail a été axé sur l'amélioration du délai du handoff au niveau physique 802.11 à quelques dizaines de millisecondes. Le déplacement des hôtes et le changement de réseau demandent souvent une reconfiguration des plusieurs paramètres au niveau IP. Dans le cas d'une mobilité locale, l'approche que nous avons choisi est de permettre aux hôtes de garder inchangées leurs adresses et de mettre en place des routes d'hôte dans le domaine local. Au contraire, pour la mobilité globale, le routage optimal à travers l'Internet nous oblige de concevoir une solution dans laquelle les hôtes mobiles changent leurs adresses IP, en conformité avec le réseau ou ils s'y trouvent. Notre solution est basée sur le principe général « de bout en bout » dans laquelle les deux hôtes impliquées dans une connexion sont les seuls à assurer le transfert de cette connexion aux nouveaux points d'attachement. Elle utilise l'interception des appels de la bibliothèque socket et des requêtes DNS ainsi que la translation locale d'adresses pour virtualiser les adresses IP réelles dans des identificateurs d'hôte stables présentés aux niveaux supérieurs.

As a result of rapid progress in research and development, today's wireless world exhibits several heterogeneous communication networks, such as cellular networks, satellite networks, wireless local area networks (WLAN), mobile ad hoc networks (MANET), and sensor networks. These networks are complementary to each other. Hence, their integration can realize a unified wireless system that has the best features of the individual networks. This has spurred much research interest in designing integrated next-generation of wireless systems (NGWS). While existing wireless networks have been extensively studied individually, the integrated wireless system brings new challenges in architecture design, system management, and protocol design. The different wireless networks use different communication technologies and are based on different networking paradigms. Therefore, it is challenging to integrate these networks such that their heterogeneities are hidden from each other and a harmonious inter-operation among them is achieved. The objective of this research is to design a scalable, secure, and robust architecture and to develop seamless mobility management protocols for NGWS. More specifically, an architecture that integrates the heterogeneous wireless systems is first proposed for NGWS. Next, a cross-layer (Layer 2 + 3) handoff management protocol is developed for NGWS. Afterward, analytical modeling is developed to investigate the handoff performance of the existing mobility management protocols for different types of applications. Finally, a framework for multi-layer mobility management is developed to support the seamless handoff support to all types of applications in NGWS.

In this study, a dynamic resource management and subscriber profile prediction scheme for mobile communication systems is presented. The aim is to achieve a high level of QoS for both handoff calls and new calls, while at the same time to improve the utilization of wireless network resources. The simultaneous satisfaction of these two actually conflicting interests will be thanks to two major key features. First, it will be due to the individual subscriber profile based prior information about handoff reservation requests that are provided by the mobile terminals. This information is based on the cell transition probabilities calculated by the mobile itself using collected information during past operations. Second, it will be due to a two-way approach implemented in the resource management processes. The two-way approach controls both the amount of reserved radio channels and the new call admission in a dynamic way, depending on the subscriber mobility and network traffic conditions.

Στην παρούσα εργασία παρουσιάζεται και αναλύεται διεξοδικά ο μηχανισμός μεταπομπής (handover) σε συστήματα κινητής επικοινωνίας. Οι μέθοδοι μεταπομπής βρίσκουν σημαντική εφαρμογή στα κυψελωτά συστήματα (cellular systems) και κατηγοριοποιούνται με βάση διάφορα χαρακτηριστικά τους, σε handovers σε σκληρά ή μαλακά, οριζόντια ή κάθετα, ελεγχόμενα από το Δίκτυο ή από την κινητή συσκευή, ή υποβοηθούμενα από την κινητή συσκευή. Σημαντικό ρόλο στις διαδικασίες handover παίζουν οι αλγόριθμοι απόφασης. Βασικές κατηγορίες αλγορίθμων απόφασης handover είναι αυτοί που στηρίζονται στη στάθμη της λαμβανόμενης ισχύος του σήματος, οι αλγόριθμοι που στηρίζονται σε fuzzy logic και οι αλγόριθμοι προτεραιότητας. Στην παρούσα εργασία προσομοιάζεται ένας αλγόριθμος προτεραιότητας γνωστός ως SJ-scheme με χρήση του λογισμικού Matlab και ειδικότερα των υποσυστημάτων του Simulink και Stateflow. Το προταθέν μοντέλο αποτελείται από έξι βασικά επιμέρους υποσυστήματα: το Υποσύστημα Εισόδου (Input Subsystem), το Υποσύστημα Καθορισμού της Χωρητικότητας των Καναλιών (Channels Size Subsystem), το Υποσύστημα Μνήμης (Memory Subsystem), το Υποσύστημα Ολοκλήρωσης Κλήσεων (Call Completion Subsystem), το Υποσύστημα των Αποτελεσμάτων (Scope Subsystem) και το Υποσύστημα Handover (Handover Subsystem) που αποτελεί την «καρδιά» του μοντέλου και περιλαμβάνει δύο βασικά blocks, ένα το οποίο υλοποιεί τη διαδικασία διαχείρισης νέων κλήσεων (New_calls_process) και ένα που υλοποιεί τη διαδικασία διαχείρισης των handovers (Handover_process). Πέραν της δημιουργίας μοντέλου προσομοίωσης, στην παρούσα εργασία παρουσιάζονται αναλυτικά και σχολιάζονται τα αποτελέσματα εκτέλεσης της προσομοίωσης και τα μετρούμενα μεγέθη. Μέσα από τις γραφικές αναπαραστάσεις που παράγονται και εξετάζονται, γίνεται αντιληπτός ο τρόπος λειτουργίας και οι ιδιαιτερότητες του προτεινόμενου μοντέλου. / In the current study the mechanism of switching between cells (handover) in mobile communication systems is presented and analyzed in detail. The handover methods are mainly applied in cellular systems and categorized according to various characteristics in hard or soft handovers, horizontal or vertical handovers, and handovers controlled by the network or the mobile device, or assisted by the mobile device. Handover decision algorithms play important role in the described processes. Main categories of handover decision algorithms are those based on the received signal strength, fuzzy logic and priority. In this study, a priority algorithm known as SJ-scheme is simulated, using Matlab software and, in particular subsystems Simulink and Stateflow. The proposed model consists of six major subsystems: Input Subsystem, Channels Size Subsystem, Memory Subsystem, Call Completion Subsystem, Scope Subsystem and Handover Subsystem which is the "heart" of the model and includes two main blocks, one that implements the new call management process and one that implements the procedure for managing handovers. Besides creating a simulation model, in this work results of running the simulation and measured data are presented and discussed. Matlab plots and graphical representations produced are examined to make clear the way that the proposed model works.

Cloud Service have been usual to solve several computer issues, some companies like Amazon or Microsoft decide invest a big amount of money to sell computer resources as PaaA or IaaS. Subsequently, new devices, now portables, emerge as common and needs cloud computing to provide resources, creating a new structure known as mobile cloud computing. Even showing several models to its architecture in mobile cloud computing, natural behavior converge to total transparency to applications and users concerning to resource location, requiring that mobile devices maintains a permanent connection and an approach that needs a procces mirroring, knows as Cloudlets. These Cloudlets should provides required resources to guarantee a cofortable perception experience to users, giving an alternate option to latency problems, local processing and unavailable connections. To obtain this quality of perception, the Cloudlet should be closest to user as possible and follow him all the time during his travel. The usual model about Cloudlets consists on services running at virtual machine, that are costly what concerns moving and startup time. As alternative this work proposes a docker container based model, which will permit a smaller startup time less tranfer data about system between datacenters evolved. This alternative shows, at proposed scenarios, is possible reduce startup overhead and moving time, benefeting users perception and opening new perspectives to implement and optimizing. / Serviços em nuvem tem se tornado uma constante para solução dos problemas computacionais convencionais, algumas empresas a exemplo da Amazon ou Microsoft investiram em infraes-trutura para vender recursos como PaaS ou IaaS. Subsequentemente novos dispositivos, agora portáteis, tem se disseminado e precisaram adotar o modelo da nuvem de provimento de recursos criando dessa maneira a Mobile Cloud Computing. Mesmo com os vários modelos de arquitetura para essa nova nuvem para dispositivos móveis, a evolução aponta em total transparência para as aplicações e usuários quanto à localização dos recursos, demandando que os equipamentos móveis necessitem uma conexão permanente e uma abordagem de espelhamento de processos conhecidas como Cloudlets. As Cloudlets devem prover recursos exigidos que garantam uma experiência de percepção de uso confortável ao usuário, contornando problemas como alta latência, processamento local e indisponibilidade de conexão. Para a obtenção dessa qualidade de percepção, a Cloudlet deve estar o mais próximo possível do usuário e acompanhá-lo durante seu deslocamento. Este trabalho apresenta uma extensão ao simulador CloudSim que possibilita a análise do efeito do deslocamento das Cloudlets através da nuvem. Como alternativa, este trabalho discute a adoção de um modelo baseado em containeres e dockers que permita um tempo de subida menor e menos dados referentes ao ambiente para serem deslocados entre os centro de processamento das cloudlets. Para avaliação da alternativa foi desenvolvida uma extensão do CloudSim que permite a mobilidade dos serviços na nuvem. Como resultado a extensão demonstrou que, para os cenários propostos, é possível reduzir o tempo e o overhead necessários para os deslocamento, beneficiando a percepção do usuário e abrindo novas premissas para avaliação, implementação e otimização

Abstract The contemporary information age is equipped with rich and affordable telecommunication services. In the future, people have even more flexibility when true wireless Internet and real-time multimedia are provided seamlessly over heterogeneous wireless networks. Optimally combining the capacity and services of the current and emerging networks requires a holistic view of mobility, resource and service management. This thesis contributes to the research and development of these hybrid systems with three main contributions. Firstly, a system architecture for vertical handoff in location-aware heterogeneous wireless networks is proposed. The proposed architecture enables the mobile node to prepare for approaching vertical handoffs and wake-up a hotspot interface. The needed communication procedures are discussed, and inter-related issues of mobility and geolocation information are considered in proportion to usability, advantages and limitations. Secondly, a framework for the analysis of vertical handoff algorithm sensitivity to various mobility parameters including velocity, handoff delay and dwell time is introduced. Handoff smoothing with a dwell-timer is analyzed as one potential scheme for optimizing vertical handoff locally. It is compared to a power based algorithm to find out its sensitivity to the changes in effective data rates, velocity of the terminal and the amount of handoff delay. The analysis focuses on the transition region, having case studies on both moving-in and moving-out scenarios. An optimal value for dwell-timer is found through simulations, showing a performance gain over power based algorithm as a function of mean throughput. The analysis is extended also to a multiple network scenario. Thirdly, experimental results on the behaviour of protocols used in wireless IP networks are presented. Prototype systems demonstrate results of using Mobile IP with a fuzzy logic algorithm for vertical handoff in a heterogeneous network environment and the role of IPv6 when using a voice application in a wireless LAN environment. Latest contributions include developing plug-and-play middleware functionalities for Symbian mobile devices, extending the use of the earlier results to state-of-the-art mobile devices.

Bakgrund: Informationsöverföring sker kontinuerligt i den perioperativa vården. Det anses vara ett riskmoment när patient och information överförs till ny personal och vårdenhet. Kontinuitet, kvalitet, effektivitet och patientsäkerhet uppnås genom att operationssjuksköterskan initierar och genomför adekvat informationsöverföring i samband med patientens kirurgiska ingrepp. Syfte: Var att belysa den perioperativa sjuksköterskans upplevelser av informationsöverföring, pre- och postoperativt. Metod: En litteraturstudie med systematiskt tillvägagångssätt i enlighet med Bettany-Saltikov och McSherry (2016). Resultatet baseras på analysen av tolv kvalitativa vetenskapliga artiklar. Resultat: Resultatet påvisade att det fanns flertalet brister i den perioperativa informationsöverföringen och att den upplevdes som komplex. Resultatet redovisades i tre huvudkategorier; Utspridd och bristfällig information, Förutsättningar för informationsöverföring samt Människans inverkan på informationsöverföring. Slutsats: Många faktorer påverkar informationsöverföringen pre- och postoperativt utifrån den perioperativa sjuksköterskans upplevelser. Då medlemmar av det kirurgiska teamet inte alltid medverkar vid den postoperativa patientöverlämningen  finns en risk för att kirurgisk information kan gå förlorad. När  informationsöverföringen brister kan det ge upphov till negativa konsekvenser för patienten. / Background: The transfer of information within perioperative care, is a continuous process. When a patient, together with the relevant patient-information is transferred to a new carer and care unit, there is considered to be an element of risk involved. Continuity, quality, efficiency and patient safety will be achieved when the operating theatre nurse initiates and implements an adequate transfer of information, in connection with the patient’s surgical procedure. Aim: To illustrate how perioperative nurses experience the pre and postoperative transfer of information. Method: A systematic literature review in accordance with  Bettany-Saltikov and McSherry (2016).  The result is based on an analysis of twelve qualitative, scientific articles. Results: The study results demonstrate that there are several deficiencies during the transfer of perioperative information, and that it is perceived as complex. The results are presented in three main categories; Scattered and inadequate information, Prerequisites for information transfer and The human influence on information transfer. Conclusion: Based on the experiences of the perioperative nurses, there are many factors which influence the pre and postoperative transfer of information. As members of the surgical team do not always participate in the postoperative patient handover, there is a risk that surgical information may be lost. There can be negative consequences for the patient when the transfer of information is inadequate.