El presente trabajo plantea una propuesta de segmentación con redes de áreas locales virtuales (VLAN) y priorización del ancho de banda con calidad de servicio (QoS) para la mejora del rendimiento y seguridad de la red de área local (LAN) en la Empresa Editora El Comercio – Planta Norte. La Empresa posee una red plana en su diseño lo cual dificulta la administración del tráfico de la red, debido a la ausencia de estándares de calidad en gestión de tráfico LAN, políticas de seguridad no alineadas a las necesidades de la Empresa y desaprovechamiento de la performance de los equipos de comunicación instalados. Esto ha ocasionado la latencia de la red en horas pico, degradándose la velocidad de transferencia por el tráfico desmedido de la información y perjudicando o retardando los procesos más importantes en la empresa en intervalos de 60 a 90 minutos. Asimismo, la información periodística enviada por los corresponsales hacia la planta, ocasiona pérdida de tiempo en acciones de “subida” y “descarga” de archivos (fotos, videos, infografías, avisos publicitarios, etc.). Adicionalmente, los parámetros de seguridad de la red no garantizan la inviolabilidad de los equipos y la manipulación de la información, lo cual representa un riesgo para la integridad y desarrollo de los procesos. Por ello, se rediseñó la red para el soporte de redes LAN virtuales y de esta manera, segmentar las áreas en subredes para un mayor nivel de protección; brindar seguridad (listas de control de acceso ACL, tecnologías emergentes en seguridad Windows Server 20008, nivel de autentificación – Radius); mejorar el consumo de ancho de banda (calidad de servicio QoS, protocolo de agregación de enlaces de control LACP, troncales, etc.); implementar nuevos protocolos en tecnología Cisco; instalar redes inalámbricas y nuevos servicios de transferencia de archivos (protocolo de transferencia de archivos FTP).

Today, the concept “unaccompanied refugee children” is common in Swedish media. The concept is both dramatic and sad. Alone - refugee - child. It is about children, who alone escape from perse- cution, war, poverty and starvation. The purpose of this study is to investigate, from a user perspec- tive and to a certain extent a goal fulfillment perspective, how some unaccompanied refugee chil- dren look at and assess how Kalmar's municipality has succeeded in taking care of and supporting the possibilities of unaccompanied refugee children to be integrated into the municipality. The result shows that the children are mostly satisfied with the municipality's efforts. The conclu- sion is furthermore that some of the goals presented in the regional program have been achieved. Some have not. Keywords: unaccompanied refugee children, integration, security, education.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18623号 / 情博第547号 / 新制||情||97(附属図書館) / 31523 / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 守倉 正博, 教授 高橋 達郎, 教授 梅野 健 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第21219号 / 情博第672号 / 新制||情||116(附属図書館) / 京都大学大学院情報学研究科通信情報システム専攻 / (主査)教授 守倉 正博, 教授 原田 博司, 教授 大木 英司 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

Den här uppsatsen är utförd i syfte att teoretiskt introducera trådlös övervakning och styrning ombordpå fartyg och undersöka om det är ett alternativ till signalkablar. Arbetet belyser regelverk ochstandarder som är relevanta för en installation av trådlöst system ombord och vad som krävs för attinstallationen inte skall bryta mot befintliga bestämmelser och undersöker om trådlösa signaler kanöverföra information trots att sändarna/mottagarna är omgivna av bland annat maskiner och skott avmetall.De allra flesta fartyg har stora mängder med signalkablar ombord som har i uppgift att överföra dataoch signaler mellan olika platser på fartyget. Dessa kablar är ofta placerade tätt intill varandra ochmonterade på ofta svåråtkomliga platser vilket innebär att kabelbrott och andra fel med kablarna ärsvåra att felsöka. Som lösning på detta kan signalerna istället överföras via ett trådlöst nätverk vilkettar bort möjligheten med kabelbrott i signalkablar och behovet att felsöka utdragna signalkablar.Informationen som överförs trådlöst blir också tillgänglig på fler platser om maskinbesättningen harhanddatorer. Alltså finns inte längre behovet av att ta sig till en kontrollpanel för att avläsa informationutan den kan avläsas med en handdator vilket ger upphov till en förenkling och effektivisering avarbetet ombord.Resultatet för arbetet nåddes främst med insamling av relevanta regelkrav och föreskrifter frånTransportstyrelsen och klassningssällskapet DNV samt artiklar och rapporter med mer sakligt teknisktinnehåll och en intervju med en systemtekniker på ett svenskt universitet. Vilket visar att det teoretisktinte finns direkta hinder för en installation av trådlös signalöverföring ombord då inga lagar behandlarexakt just installationen av system med trådlösa signaler. Dock finns krav från klassningssällskap förfunktion och utförande av trådlösa nätverk. Utöver det står det i flera regelverk och standarder attalternativa system som har samma funktion som det befintliga kan godkännas så länge det inte gerupphov till försämrad säkerhet eller driftstörningar. Hänvisning till annan forskning visar också att dentrådlösa signalöverföringen går att bygga upp så att det inte störs ut av allt i fartyget som är byggt avmetall. / This essay is written with the purpose of theoretically introducing wireless monitoring and controllingon board ships and examine whether it is an alternative to signal cables that would work in reality. Theessay illustrates the regulations and standards that are relevant for the installation of a wireless systemon board and what is required for the installation not to violate existing regulations and examineswhether wireless signals can theoretically transmit information despite the fact that the signals aresurrounded by the ships metal hull.A majority of vessels have large ammounts of signal cables installed on board which have the purposeof transmitting data and signals between different locations on board. These signal cables are ofteninstalled tightly together and in difficultly accesible places which implicates that breakage in cables orother cable related issues are hard to troubleshoot and resolve. As a solution to this problem, thesignals that these cables are meant to carry can be transmitted wirelessly which completely eliminatescable breakage and the need of troubleshooting cable related issues in places that are hard to access.The information thats being transmitted wirelessly also becomes accesible in multiple places on boardas long as the crew on board uses handheld computers that are connected to the local network.Therefore there i no need to enter the control room to read the information that is being transmitted,but can instead be recieved wirelessly in the entire engine room using a handheld computer. Thismakes working in the engine room both easyer and more efficient.The results of this essay were achieved by collecting information from relevant regulations anddirectives from Transportstyrelsen and DNV and also articles and reports with substantive technicalcontent as well as a interview with a systemtechnician at a swedish university. The results shows thattheoretically there are no direct obstacles for the installation of wireless signal transmitters on board.As there are no specific regulations regarding wireless systems that directly correlate with what thisessay is mentioning. It is generally written that when it comes to electrical installations, the cablesbeing installed must, amongst other demands, meet certain dimensions and have a certain distance toeach other to prevent unnecessary magnetic fields to occur. This is not applicable to the wirelesssystem that the essay deals with as the essay is about eliminating signal cables. However it I stated inseveral regulations and standards that alternatives to already existing systems that have correspondingfunctions to the already existing systems can be considered as long as the alternative system does notcause operational disruptions or impair safety. Reference to other research shows that wireless signaltransmitting can be built in such ways that the wireless signals are not disrupted by the metal hull ofthe vessel.

Lan is a high prevalence red blood cell antigen present in the majority of the populations that belong to the Lan (Langereis) blood group system. Anti-Lan antibody is an immunoglobulin G (IgG) antibody that is known to cause delayed hemolytic transfusion reactions in adults as well as hemolytic disease in fetuses and newborns, however with variable clinical significance ranging from mild to severe. We present a 58-year-old woman with diffuse abdominal pain and a large gastric ulcer causing gastric outlet obstruction. She underwent antrectomy and Billroth I reconstruction surgery without complications. The patient's hemoglobin upon presentation was 10g/dL and dropped acutely post-operatively to 6.4 g/dL requiring blood transfusion. The patient developed acute respiratory distress within minutes of starting a packed red blood cell (pRBC) transfusion, requiring discontinuation. Laboratory testing demonstrated pan-reactivity with additional reference testing demonstrating an anti-Lan antibody. The rarity of Lan negative pRBC units is a challenge in managing such patients requiring blood transfusions. Autologous blood donation or donation by a compatible family member is another option to consider in these rare cases.

<p>Wireless LAN (WLAN) mesh networks are now being used to deploy Wi-Fi coverage in a wide variety of outdoor applications. In these types of networks, conventional WLAN mesh nodes must be operated using continuous electrical power connections. This requirement may often be very expensive, especially when the network includes expansive outdoor wireless coverage areas. An alternative is to operate some of the WLAN mesh nodes using an energy sustainable source such as solar or wind power. This eliminates the need for a fixed power connection, making the node truly tether-less and allowing for more flexibility in node positioning. The cost of the battery and the solar panel or wind turbine can be a significant fraction of the total node cost, therefore the resource allocation must be performed optimally.</p><p>In this thesis we investigate this problem. First, we present geographic provisioning results for solar and wind powered WLAN mesh nodes. The results suggest that in certain geographic locations a hybrid wind/solar powered WLAN mesh node is the optimum minimum cost configuration. The results also provide strong motivation for introducing power saving to the IEEE 802.11 standard. We then consider the problem of cost-optimal node placement in a hybrid network containing traditional and energy sustainable nodes. Our results show that there is a significant improvement in cost that can be obtained using the proposed methodology. Finally, we consider the problem of energy management in these networks. A control algorithm is proposed that uses access to publicly available meteorological databases. We show that the proposed algorithm minimizes node outage and performs favorably compared to the analytic performance bounds. Overall, the work in this thesis develops analytical and simulation models which investigate the key aspects pertaining to resource allocation in energy sustainable WLAN mesh networks.</p> / Thesis / Doctor of Philosophy (PhD)

Mobile handset manufacturers have begun to include wireless LAN (WLAN) interfaces in their cellular handsets. This allows users to access WLAN networks when they are available and to revert to conventional cellular communications otherwise. In this way the handset can dynamically use the "best" available network, by switching connections between the two network interfaces. This switching is referred to as a vertical handoff (VHO). When handling real-time connections, handsets must be capable of performing a seamless vertical handoff. This occurs when the interface switching does not disrupt the quality of service requirements of the active connections. Vertical handoffs are generally time consuming, and this delay creates a difficult problem since WLAN coverage can be lost very abruptly. In this thesis, we propose and investigate several methods of mitigating this problem. A solution based on using a Vertical Handoff Support Node (VHSN) is proposed. When the WLAN link is lost, the VHSN is able to quickly redirect packets through the local cellular base-station during the time that handoff is taking place. This approach can eliminate VHO link loss. It is shown that the act of WLAN-to-cellular handoff can result in a severe bandwidth deficit problem on the WLAN. A novel bandwidth reservation and securing mechanism is proposed which overcomes this problem and performs significantly better than schemes based on modified versions of the static guard channel scheme used in cellular networks. The work is characterized by simulation and analytic models which investigate the key performance aspects of this type of system. / Thesis / Doctor of Philosophy (PhD)

No description available.

<p> Wireless LAN mesh networks (WMNs) are a cost effective way of deploying wireless LAN (WLAN) coverage over extended areas. As WMNs become more populated, scalability issues may arise due to the co-channel interference which is inherent in publicly available RF (radio frequency) channels. This co-channel interference can severely degrade network capacity and link reliability and may eventually make it impossible to operate with the frequency channels for which the network was originally designed. In this thesis, this problem is addressed by selectively installing supplementary free-space optical (FSO) links when RF link performance has deteriorated. The frequency assignment problem is solved using a heuristic technique based on a genetic algorithm. In order to determine the quality of the results, the proposed algorithm is compared with a lower bound solution obtained using an Integer Linear Programming (ILP) formulation.</p> <p> Another advantage of FSO links is that they may reduce node power consumption compared with conventional RF links. This may be an important consideration in cases where power consumption at the nodes is important, such as in solar powered mesh networks. Power consumption estimates of RF and FSO links are obtained and compared for different data rates. This data is then used along with historical solar insolation data to estimate the solar panel and battery sizes required to guarantee a given node outage probability. The results show that no extra provisioning is required for replacing the deployed wireless nodes with new FSO links.</p> / Thesis / Master of Applied Science (MASc)