Όσο οι δυνατότητες των φορητών συσκευών, όπως κινητά τηλέφωνα, PDA’s, laptops και smartphones γίνονται ολοένα μεγαλύτερες, η αποθήκευση κοινωνικών δεδομένων σε αυτές έχει γίνει πλέον ανάγκη και τα κοινωνικά δίκτυα που αναπτύσσονται μέσω του internet έχουν κατακλίσει τον παγκόσμιο ιστό, τόσο μεγαλύτερη πρέπει να είναι και η ευκολία του χρήστη να χρησιμοποιήσει και να συγχρονίσει όλες αυτές τις πληροφορίες, σε όλες τις συσκευές που έχει στην κατοχή του χωρίς ιδιαίτερο κόπο. Στην συγκεκριμένη διπλωματική παρουσιάζουμε ένα συνδυασμό android application και server services, που δίνει την δυνατότητα στον εκάστοτε χρήστη, που έχει στην κατοχή του λογαριασμό στο facebook και συσκευή με λειτουργικό σύστημα Android 1.6 (υπάρχει συμβατότητα μέχρι και το Android 2.3), να συγχρονίσει τις επαφές του κινητού τηλεφώνου του με αυτές από το facebook, εισάγοντας κοινωνικά δεδομένα, όπως ημερομηνία γέννησης, τελευταία ανανέωση του status και username, από την βάση δεδομένων του facebook σε κάθε αντίστοιχη επαφή που υπάρχει στο κινητό τηλέφωνο. Βασικός μας σκοπός ήταν η απλότητα στην χρήση της εφαρμογής και η ασφάλεια στην διακίνηση και αποθήκευση των κοινωνικών δεδομένων αφού πρόκειται για προσωπικές πληροφορίες του κάθε χρήστη. Στην συνέχεια παρουσιάζουμε τις τεχνικές λεπτομέρειες και τέλος, τους μελλοντικούς μας στόχους και προτείνουμε προοπτικές για μελλοντική εργασία στο συγκεκριμένο θέμα. Στο παράρτημα παρατίθεται αναλυτικά όλος ο κώδικας που χρησιμοποιήθηκε για την ανάπτυξη αυτής της διπλωματικής εργασίας. / --

Ο σκοπός της διπλωματικής εργασίας είναι η απεικόνιση της βιοϊατρικής πληροφορίας με πρωτότυπο τρόπο, δίνοντας έμφαση τόσο στον σχεδιασμό και στην ανάπτυξη μίας φιλικής διεπαφής για τον χρήστη όσο και στην απόκτηση τεχνικής γνώσης από μέρους μου. Έτσι, μελετήθηκαν υπάρχουσες εφαρμογές-τεχνολογίες και οι αντίστοιχες δυνατότητες που προσέφεραν, σε συνδυασμό πάντα με τις απαιτήσεις και τις ανάγκες των ιατρών. / The subject of the present diploma is the imaging of biomedical information in an original way, emphasizing both the design and development of a user friendly interface and the acquisition of technical knowledge for me. Thus, studied existing applications and technologies and their respective capabilities offered, I tried to make a system always in combination with the demands and the needs of the doctors.

Background. High-availability (HA) is a cloud’s ability to keep functioning after one or more hardware or software components fail. Its purpose is to minimize the system downtime and data loss. Many service providers guarantee a Service Level Agreement including uptime percentage of the computing service, which is calculated based on the available time and system downtime excluding the planned outage time. The aim of the thesis is to perform the update of the virtual machines running in the cloud without causing any interruptions to the user by redirecting the resources/services running on them to an alternative virtual machine before the original VM is updated. Objectives. The objectives for the above aim include. • The first objective is to investigate existing solutions for high-availability and, if possible, adapt them to our aim. The alternative is to design our own solution. • The second objective is to implement the solution in an Open Stack environment. As an alternative, we can try a smaller scale implementation under a virtualization platform such as Virtual Box. • The final objective is to run experiments to quantify the effectiveness of our solution in terms of overhead and degree of seamlessness to the users. Methods. An environment with multiple virtual machines may be created to represent multiple virtual servers in the cloud. The state of service provided by the primary virtual machine is saved to persistent storage and the client is redirected to an alternate virtual machine. At that point the primary virtual machine may reboot for an update or any other issues. Results. In the case of CPU Utilization, the mean CPU utilization on Server and Host in scenario 1 are 0.34% and 3.2% respectively. The mean CPU utilization on Primary server and Host in scenario 2 during the failover cycle are 2.0% and 9.7% respectively. The mean CPU utilization on Secondary server and Host in scenario 2 during failover cycle are 0.99% and 8.0% respectively. For the Memory Utilization, the mean Memory usage on server in scenario 1 is 16%. The mean Memory usage on primary server and secondary server in scenario 2 during failover cycle are 37% and 48% respectively. The Time for failover of the high availability environment remains for 6.8 seconds and the time for the off-line node to rejoin the cluster as on-line when told would take 1.5 seconds. The network traffic is measured in Kilobits per second, it is 1.2 Kilobits per second on port 80 in scenario 2 and is 1.4 Kilobits per second between the client and the server in scenario 1. In addition, data traffic on ports 5405, 2224 and 7788 are captured where port 5405 (Pacemaker/Corosync) contains UDP traffic, port 2224 (Pcsd) contains TCP traffic and port 7788 (DRBD) contains TCP traffic. The traffic captured on these ports represent network overhead due to HA. During failover cycle an additional traffic of 45Kb/s, 1.2Kb/s. 7.0Kb/s flow on 5405, 2224 and 7788 ports respectively. Conclusions. From our experiment results we can say that the overhead to handle live updates on high availability environment is approximately 1.1 - 1.7 % of CPU higher in HA mode than when a stand-alone server is used. The overhead is around 21 - 32 % higher in terms of memory utilization for the live updates on the HA system than for the standard server. The network traffic overhead induced by the ports used by high availability environment (5405, 2224, 7788) is approximately 53 Kilobits /Second while the minimum overhead is approximately 16 Kilobits / Second. The Final and the important metric is the Failover time which tells the seamlessness of the service as the environment needs to provide the services uninterrupted to the users. The failover time of the HA model is about just 6.8 seconds leaving the environment highly available. However, the user may notice slight interruption for the requests made during this span.

This thesis covers the development of web applications with modern programming languages and technologies. The objective of thesis is the research and analysis of modern technologies and subsequent selection of particular programming languages, frameworks and database for development of web application applying those techniques. Based on analysis of modern trends I chose the following technologies: backend development using popular Spring framework based on Java EE, frontend implementation using one of the most widespread scripting languages JavaScript and its known framework AngularJS developed by Google. For data persistence I chose NoSQL database MongoDB. I provided detailed documentation of each implementation step: project definition, requirements analysis, design, implementation and testing.

Sistemas distribuídos representam uma plataforma ideal para implementação de sistemas computacionais com alta confiabilidade e disponibilidade devido a redundância fornecida por um grande número de estações interligadas. Falhas de um servidor podem ser contornadas pela reconfiguração do sistema. Entretanto falhas em seqüência que afetem múltiplas estações comprometem não apenas o desempenho do sistema, mas também a continuidade do serviço e sua confiabilidade. Assim, servidores falhos, que tenham sido isolados do sistema, devem ser reintegrados tão logo quanto possível para não comprometer a disponibilidade do sistema computacional. Este trabalho trata da atualização do estado de servidores e da troca de informação que o servidor recuperado realiza para integrar-se aos demais membros do sistema através de um procedimento chamado reintegração do servidor. E assumido um ambiente distribuído que garante alta confiabilidade em aplicações convencionais através da técnica de replicação de arquivos. O servidor a ser reintegrado faz parte de um grupo de replicação e volta a participar ativamente do grupo tão logo seja reintegrado. Para tanto, considera-se a estratégia de replicação por copia primaria e um sistema distribuído experimental, compatível com o NFS, desenvolvido na UFRGS para aplicar a reintegração de servidor. Os métodos de atualização de arquivos para a reintegração do servidor foram implementadas no ambiente UNIX. / Distributed systems are an ideal platform to develop high reliable computer applications due to the redundancy supplied by a great number of interconnected workstations. Failed stations can be masked reconfiguring the system. However, sequential faults, that affect multiple stations, not just decrease the performance of the system, but also affect the continuity of the service and its reliability. Thus, failed stations working as servers, that have been isolated from the system, should be reintegrated as soon as possible to not impair the system availability. This work is exactly about methods to update the state of failed servers. It deals also with the change of information that the recovered server accomplishes to be integrated to the other members of the service group through a process called reintegration of server. It is assumed a distributed environment that guarantees high reliability in conventional applications through replication of files. The server to be reintegrated is part of a replication group and it participates actively of the service group again as soon as it is reintegrated. Our approach is based on a primary copy. The file actualization methods to the reintegration of server were implemented in an UNIX environment. To illustrate our approach we will describe how the integration of repaired server can be made a fault-tolerant system. The experimental distributed system, compatible with NFS, was designed at the UFRGS.

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No. of bitstreams: 1 Dissertação de Mestrado - Maryangela Aguiar Bittencourt.pdf: 1163308 bytes, checksum: 31d019a4e667159775e949a897db9932 (MD5) Previous issue date: 2008 / School of Government and Professional Server is the subject of this thesis aimed at analyzing the mission of each and its contribution to the training of all operators in the state administrative structure. The experiences in the field of management training, capacity building and training of civil servants in public administration from national and international experiences, allow the establishment of information concerning the professional profiles required for the Brazilian public administration in the current context and the appropriate institutions for the production these profiles. To this end, reconstructs the institutional history of ENAP - National School of Public Administration / Brazil and brings slopes analysis to be tested in other schools. In order to promote debate the Latin American context is widespread, as the attempt to periodization and analysis of 80 years raising a general review of common features that point to help contextualize and expand the debate that rages in each country about the prospects these government schools. In the 80's is emphatically defended the existence and definition of an ideal profile of professional public administration, today, the discourse has changed since 90 years, the rapid degree of change and complexity installed within organizations by technological advance and the rearrangement of the economic and cultural boundaries derived from globalization have highlighted the need for treatment and more careful scrutiny to the issue, requiring additional effort to escape from solutions in mixtures of a profoundly heterogeneous. Thus, it takes as a case study the experiences of ESPE and FESPM both located in the city of Manaus in Amazonas state for review of the purpose of each of the schools, where they helped train new cadres of public servants and also, prepared new leadership for the development and improvement of the state machine. The methodological guidelines used were based on two criteria Vergara (2006), about the purposes and the means with basic technical and empirical-analytic approach, the means of investigation was the documentary, literature and exploratory (field research, through interviews with former teachers and former students of schools). The results of the collective responses of the subjects were consolidated into a single speech when the same opinion emphasizing the central idea of each of the speeches delivered and how many people the same idea. It was concluded that the government schools can contribute to the professionalization of public servants and recommended development of programs for schools that will graduate in public administration, developing skills for the public servant and advice to create plans for capacity building of bodies’ government playing a significant role in personal and professional public servant. / Escolas de Governo e a Profissionalização do Servidor é o tema desta dissertação objetivando analisar a missão de cada uma delas e a sua contribuição para a capacitação de todos os operadores da estrutura administrativa estatal. As experiências no campo de formação de quadros, capacitação e treinamento do funcionalismo na administração pública, a partir de experiências internacionais e nacionais, permitem o estabelecimento de indicações acerca dos perfis do profissional necessário à administração pública brasileira no atual contexto e das instituições adequadas à produção desses perfis. Para tanto, reconstrói a história institucional da ENAP – Escola Nacional de Administração Pública/Brasil buscando levantar pistas de análise a serem testadas nas demais escolas. A fim de promover debate o contexto latino-americano é generalizado, como a tentativa de periodização e a análise dos anos 80 suscitando uma reflexão de conjunto que aponte traços comuns, para ajudar a contextualizar e ampliar o debate que se trava em cada país sobre as perspectivas destas escolas de governo. Na década de 80 se defendia enfaticamente a existência e definição de um perfil ideal de profissional para administração pública; hoje, o discurso mudou, já que nos anos 90, o acelerado grau de mudanças e a complexidade instalada no interior das organizações pelo avanço tecnológico e pelo rearranjo das fronteiras econômico-culturais derivadas do processo de globalização têm evidenciado a necessidade de tratamento mais cauteloso e minucioso à questão, requerendo, esforço adicional para escapar de soluções homogeneizadoras de uma realidade profundamente heterogênea. Sendo assim, toma como estudo de caso as experiências da ESPEA e da FESPM ambas situadas na cidade de Manaus no Estado do Amazonas procurando analisar qual a finalidade de cada uma das escolas, se elas contribuíram para formar novos quadros de servidores públicos e se, também, prepararam novas lideranças para o desenvolvimento e o aprimoramento da máquina estatal. As diretrizes metodológicas utilizadas foram baseadas em dois critérios de Vergara (2006), quanto aos fins e quanto aos meios, com pressuposto técnico e abordagem empírico-analítica, cujo meio de investigação foi a documental, bibliográfica e exploratória (pesquisa de campo, por meio de entrevistas com ex-professores e ex-alunos das escolas). Os resultados das respostas dos sujeitos coletivos foram consolidados num único discurso quando de uma mesma opinião destacando a idéia central de cada um dos discursos e quantas pessoas emitiram a mesma idéia. Concluiu-se que as escolas de governo podem contribuir para a profissionalização do servidor público e recomendou-se desenvolvimento de programas pelas Escolas que deverão formar em gestão pública; desenvolver competências para o servidor público e criar assessoria para elaboração de planos de capacitação dos órgãos da administração pública exercendo um papel significativo na vida pessoal e profissional do servidor público.

Sistemas distribuídos representam uma plataforma ideal para implementação de sistemas computacionais com alta confiabilidade e disponibilidade devido a redundância fornecida por um grande número de estações interligadas. Falhas de um servidor podem ser contornadas pela reconfiguração do sistema. Entretanto falhas em seqüência que afetem múltiplas estações comprometem não apenas o desempenho do sistema, mas também a continuidade do serviço e sua confiabilidade. Assim, servidores falhos, que tenham sido isolados do sistema, devem ser reintegrados tão logo quanto possível para não comprometer a disponibilidade do sistema computacional. Este trabalho trata da atualização do estado de servidores e da troca de informação que o servidor recuperado realiza para integrar-se aos demais membros do sistema através de um procedimento chamado reintegração do servidor. E assumido um ambiente distribuído que garante alta confiabilidade em aplicações convencionais através da técnica de replicação de arquivos. O servidor a ser reintegrado faz parte de um grupo de replicação e volta a participar ativamente do grupo tão logo seja reintegrado. Para tanto, considera-se a estratégia de replicação por copia primaria e um sistema distribuído experimental, compatível com o NFS, desenvolvido na UFRGS para aplicar a reintegração de servidor. Os métodos de atualização de arquivos para a reintegração do servidor foram implementadas no ambiente UNIX. / Distributed systems are an ideal platform to develop high reliable computer applications due to the redundancy supplied by a great number of interconnected workstations. Failed stations can be masked reconfiguring the system. However, sequential faults, that affect multiple stations, not just decrease the performance of the system, but also affect the continuity of the service and its reliability. Thus, failed stations working as servers, that have been isolated from the system, should be reintegrated as soon as possible to not impair the system availability. This work is exactly about methods to update the state of failed servers. It deals also with the change of information that the recovered server accomplishes to be integrated to the other members of the service group through a process called reintegration of server. It is assumed a distributed environment that guarantees high reliability in conventional applications through replication of files. The server to be reintegrated is part of a replication group and it participates actively of the service group again as soon as it is reintegrated. Our approach is based on a primary copy. The file actualization methods to the reintegration of server were implemented in an UNIX environment. To illustrate our approach we will describe how the integration of repaired server can be made a fault-tolerant system. The experimental distributed system, compatible with NFS, was designed at the UFRGS.

Les serveurs informatiques permettent de mettre en œuvre un large éventail de services en ligne et d'applications telles que les services Web, les services de messagerie ou les services de base de données. Cependant, leur configuration ad hoc soulève des problématiques cruciales liées à la performance, la disponibilité et le coût économique des applications. Dans cette thèse, nous étudions l'impact de la configuration des serveurs sur le compromis central entre performance et disponibilité du service. Dans une première partie, nous modélisons le comportement de serveurs uniques à l'aide d'approximations fluides et développons des lois de commandes novatrices pour le contrôle d'admission sur les systèmes de serveurs centralisés. Nous proposons plusieurs lois de commande pour différentes combinaisons d'objectifs de qualité de service et de niveau de service. Parmi elles, AM-C garantit un objectif de performance du service en maximisant sa disponibilité; PM-C garantit un objectif de disponibilité du service en maximisant sa performance. Nous évaluons expérimentalement le modèle ainsi que les stratégies de contrôle sur TPC-C, un benchmark industriel reconnu qui reproduit un service d'e-commerce, implémenté sur le serveur de base de données PostgreSQL. Nos expériences montrent que les techniques proposées améliorent jusqu'à 30% les performances du service tout en garantissant les contraintes de disponibilité. Dans une deuxième partie, nous étendons ce travail aux systèmes de serveurs distribués, qui sont largement utilisés par les applications Internet évoluant sur des systèmes multi-niveaux hébergés par des clusters de serveurs. Nous présentons un modèle de serveur distribué comme un modèle continu non linéaire en faisant une analogie avec les systèmes transferts de fluide. Nous formalisons alors un problème d'optimisation pour le contrôle de ces systèmes. Nous fournissons un contrôle d'admission qui permet d'obtenir la disponibilité de service la plus élevée tout en garantissant un objectif de performance. Une évaluation numérique du modèle proposé et du contrôle distribué associé est présentée et montre que la configuration optimale de ces systèmes n'est pas intuitive. / Server technology provides a means to support a wide range of on-line services and applications, such as web services, e-mail services, database services. However, their ad hoc configuration poses significant challenges to the performance, availability and economical costs of applications. In this thesis, we examine the impact of server configuration on the central trade-off between service performance and service availability. First, we model the behavior of single servers using fluid approximations. Second, we develop novel ad- mission control laws of central server systems. We provide several control laws for different combinations of quality-of-service and service level objectives. Among them, AM-C , the availability-maximizing admission control law, achieves the highest service availability while meeting given performance objective; PM-C is a performance-maximizing ad- mission control law that meets a desired availability target with the highest performance. We evaluate our fluid model and control techniques on the TPC-C industry-standard benchmark that implements a warehouse running on the PostgreSQL database server. Our experiments show that the proposed techniques successfully improve performance by up to 30 % while guaranteeing availability constraints. Furthermore, we extend this work to distributed server systems, that are widely used by Internet applications in the farm of server clusters and multi-tier systems. We present a distributed server model as a non-linear continuous-time model using analogies with fluid transfer. We then state an optimization problem for the control of distributed server systems. We provide an admission control that allows to get the highest service availability while a target performance level is guaranteed. Numerical evaluations of the proposed distributed model and control are presented, and show that the optimal configuration of such systems is not intuitive.

Examensarbete ”hur ser säkerheten ut” valdes på ett eget initiativ då jag upplever att det finns ett stort behov av att engagera verksamheter att lära sig mer om hur information och nätverk ska hanteras på ett säkerhet sätt. Genom en kvantitetundersökning bland verksamheter kunde en kartläggning göras av hur verksamheterna hanterar sin information och nätverksmiljö. Med hjälp av undersökningen resultat och faktainsamling kunde fakta om säkerhet tas fram till verksamheterna. För att presentera informationen på bästa sätt skapades en webbapplikation. Arbete med webbapplikationen innebar att en server sattes upp som en back-front och serverar HTML, CSS och Python kod för att kunna generera unika data till användarna. I slutet av projektet fick tredjeparts program analysera webbapplikationen samt en testgrupp utvärdera informationen och ett underlag för vidare utveckling av webbapplikation tas fram. / The thesis ”how does the security look like” was chosen on my own initiative, becasue there is a great need to engeage small bussnies in leraning more about how information and networks should handle safely. Through a quantitative survey among small businsses a survey could be made of how small businsses handle their information and network environment. Using the results of the survey and the collection of facts, customer facts about how security should look like can be created för small businesses. To present facts in the best way, a web application was created. Working with the web application meant that a server was installed. As well as a website with HTML and CSS code. Scripts were created to generate unique data for the user (small businesses) At the end of the project, third party programs were able to analyze the web application and a test group evaluate the information and web application to provide a basis for further development.

Made available in DSpace on 2015-05-14T12:20:09Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2411819 bytes, checksum: 51fe6bb46fd7bf88580d58a7bd308d63 (MD5) Previous issue date: 2014-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research aims to identify the State Department of Revenue employees acceptance in relation to the adoption SIGECAP. To check the acceptance or this system it was applied the Technology Acceptance Model (TAM). The research is characterized as being exploratory and descriptive with data collection conducted through a user survey. As a result, it was possible to verify that the SIGECAP is easy to use, according to the obtained results, the perceived ease of use has led the largest percentage (37.33%) of data variability. The second factor (use intention) explains 11.99% of the data, the third factor (perceived utility) explains 8.26% of the data, the fourth factor (external variable) explains 6.071% of the data structure and the fifth factor (Hardware Resources) obtained 5.73%. Future research is required to investigate possible digital limitations and also the interrelationships involving servers that have not master the IT resources and those who do not know the SIGECAP. / Esta pesquisa tem como objetivo identificar a aceitação dos servidores da Secretaria de Estado da Receita (SER), na adoção do SIGECAP. Para se checar a aceitabilidade desse sistema, foi utilizado como ferramenta o modelo teórico de aceitação de tecnologia TAM. A pesquisa caracteriza-se como exploratória e descritiva, com coleta de dados realizada por meio de aplicação de questionário. Como resultado, foi possível detectar que o SIGECAP é fácil de usar, pois, de acordo com o resultado obtido, a facilidade de uso percebida levou o maior percentual (37,33%) da variabilidade dos dados. O 2º fator (Intenção de uso) explica 11,99% dos dados; o 3º fator (Utilidade percebida) explica 8,26% dos dados; o 4º fator (variável externa) explica 6,071% da estrutura dos dados, e o 5º fator (Recursos em Hardware) obteve 5,73% dos dados. Futuras pesquisas são necessárias para investigar eventuais limitações digitais e as inter-relações que envolvem os servidores que ainda não dominam a informática e os que não conhecem o SIGECAP.