Avec l'avènement des technologies de Cloud computing et son adoption, les entreprises et les institutions académiques transfèrent de plus en plus leurs calculs et leurs données vers le Cloud. Alors que ce progrès et ce modèle simple d'accès ont eu un impact considérable sur notre communauté scientifique et industrielle en termes de réduction de la complexité et augmentation des revenus, les centres de données consomment énormément d'énergie, ce qui se traduit par des émissions plus élevées de C02. En réponse, de nombreux travaux de recherche se sont focalisés sur les enjeux du développement durable pour le Cloud à travers la réduction de la consommation d'énergie en concevant des stratégies d'efficacité énergétiques. Cependant, l'efficacité énergétique dans l'infrastructure du C!oud ne suffira pas à stimuler la réduction de • l'empreinte carbone. Il est donc impératif d'envisager une utilisation intelligente de l'énergie verte à la fois au niveau de l'infrastructure et de l'application pour réduire davantage l'empreinte carbone. Depuis peu, certains fournisseurs de Cloud computing alimentent leurs centres de données avec de l'énergie renouvelable. Les sources d'énergie renouvelable sont très intermittentes, ce qui crée plusieurs défis pour les gérer efficacement. Pour surmonter ces défis, nous étudions les options pour intégrer les différentes sources d'énergie renouvelable de manière réaliste et proposer un Cloud energy broker qui peut ajuster la disponibilité et la combinaison de prix pour acheter de l'énergie verte dynamiquement sur le marché de l'énergie et rendre les centres de données partiellement verts. Puis, nous introduisons le concept de la virtualisation de l'énergie verte, qui peut être vu comme une alternative au stockage d'énergie utilisé dans les centres de données pour éliminer le problème d'intermittence dans une certaine mesure. Avec l'adoption du concept de virtualisation, nous maximisons l'utilisation de l'énergie verte contrairement au stockage d'énergie qui induit des pertes d'énergie, tout en introduisant des Green SLA basé sur l'énergie verte pour le fournisseur de services et les utilisateurs finaux. En utilisant des traces réalistes et une simulation et une analyse approfondie, nous montrons que la proposition peut fournir un système efficace, robuste et rentable de gestion de l'énergie pour le centre de données. Si une gestion efficace de l'énergie en présence d'énergie verte intermittente est nécessaire, la façon dont les applications Cloud modernes peuvent tirer profit de la présence ou l'absence d'énergie verte n'a pas été suffisamment étudiée. Contrairement aux applications Batch, les applications Interactive Cloud doivent toujours être accessibles et ne peuvent pas être programmées à l'avance pour correspondre au profil d'énergie verte. Par conséquent, cette thèse propose une solution d'autoscaling adaptée à l'énergie pour exploiter les caractéristiques internes des applications et créer une conscience d'énergie verte dans l'application, tout en respectant les propriétés traditionnelles de QoS. Pour cela, nous concevons un contrôleur d'application green qui profite de la disponibilité de l'énergie verte pour effectuer une adaptation opportuniste dans une application gérée par un contrôleur orienté performance. L'expérience est réalisée avec une application réelle sur Grid5000 et les résultats montrent une réduction significative de la consommation d'énergie par rapport à l'approche orientée performance, tout en respectant les attributs traditionnels de QoS. / With the advent of cloud enabling technologies and adoption of cloud computing, enterprise and academic institutions are moving their IT workload to the cloud. Although this prolific advancement and easy to access model have greatly impacted our scientific and industrial community in terms of reducing complexity and increasing revenue, data centers are consuming enormous amount of energy, which translates into higher carbon emission. In response, varieties of research work have focused on environmental sustainability for Cloud Computing paradigm through energy consumption reduction by devising energy efficient strategies. However, energy efficiency in cloud infrastructure alone is not going to be enough to boost carbon footprint reduction. Therefore, it is imperative to envision of smartly using green energy at infrastructure and application level for further reduction of carbon footprint. In recent years, some cloud providers are powering their data centers with renewable energy. The characteristics of renewable energy sources are highly intermittent which creates several challenges to manage them efficiently. To overcome the problem, we investigate the options and challenges to integrate different renewable energy sources in a realistic way and propose a Cloud energy broker, which can adjust the availability and price combination to buy Green energy dynamically from the energy market in advance to make a data center partially green. Later, we introduce the concept of Virtualization of Green Energy, which can be seen as an alternative to energy storage used in data center to eliminate the intermittency problem to some extent. With the adoption of virtualization concept, we maximize the usage of green energy contrary to energy storage which induces energy losses, while introduce Green Service Level Agreement based on green energy for service provider and end users. By •using realistic traces and extensive simulation and analysis, we show that, the proposal can provide an efficient, robust and cost-effective energy management scheme for data center. While an efficient energy management in the presence of intermittent green energy is necessary, how modern Cloud applications can take advantage of the presence/absence of green energy has not been studied with requisite effort. Unlike Batch applications, Interactive Cloud applications have to be always accessible and car not be scheduled in advance to match with green energy profile. Therefore, this thesis proposes an energy adaptive autoscaling solution to exploit applications internal to create green energy awareness in the application, while respecting traditional QoS properties. To elaborate, we design green energy aware application controller that takes advantage of green energy availability to perform opportunistic adaptation in an application along with performance aware application controller. Experiment is performed with real life application at Grid5000 and results show significant reduction of energy consumption while respecting traditional QoS attributes compared to performance aware approach.

This diploma thesis is about a proposal of an information system for the company Smart Connections s.r.o. The diploma thesis is divided into three parts which are theoretical, analytical and proposal part. The aim of this thesis is to analyse current state of the company's information system and to identify its drawbacks and weaknesses. Based on that a proposal of new information system will be made. The last part will focus on benefits and economic evaluation of the new informative system.

Tato diplomová práce staví na základech položených v rámci semestrální práce se stejným názvem. Na začátku jsou nejprve uvedeny základní vlastnosti slunečního záření nutné k pochopení výpočtu tzv. performance ratio. Dále jsou popsány solární senzory vyvinuty v ReRa Solutions, které byly zdrojem dat. V následné literární rešerši jsou zkoumány alternativy k nespolehlivému Wi-Fi připojení senzoru a za nejvýhodnější řešení je považována LoRa. V praktické části je detailně popsán proces návrhu a vývoje single page aplikace. Tato aplikace umožňuje jak ukládání dat ze senzorů do databáze, tak jejich opětovné čtení a zobrazení zpět uživateli ve srozumitelné podobě. Aplikace těží z využití moderních programovacích jazyků a frameworků (např. Kotlin, Spring, TypeScript, React, Material-UI). Databázový model, který byl navržen na základně skutečného využití, představuje koncept tzv. monitorované oblasti, což přináší široké konfigurační možnosti. Poté byl model přenesen do databáze ve formě programovatelných entit. Komunikace mezi klientem a serverem podporující autentifikaci na základě uživatelských rolí byla implementována přes REST API. Přes grafické rozhraní aplikace je možné konfigurovat prostředí podle uživatelských požadavků a zobrazit interaktivní grafy obsahující senzory naměřená data. Aplikace byla nasazena v Google Cloudu s oddělenou databází.

Rapporten behandlar utvecklingen av ett system som möjliggör för rapportering och granskning av avfallsdata. Systemet består av en mobilapplikation och en webbapplikation som utvecklats med React Native respektive React, en databas som utvecklats med MySQL och en back-end bestående av tjänster som erbjuds av Amazon Web Services. I AWS används tjänster som tillåter hantering av mobilapplikation, webbapplikation, databas och användare. Systemet utvecklades av åtta studenter vid Tekniska högskolan vid Linköpings universitet på uppdrag av det australiensiska företaget EcCell. Projektet resulterade i framtagningen av produkten Trace the Waste med nästan alla önskade funktionaliteter. I rapporten diskuteras även vad som hade kunnat göras annorlunda i utvecklingen med hjälp av andra verktyg. Rapporten drar slutsatser om bland annat varför produkten ger värde för kunden och hur den agila arbetsmetoden Scrum påverkat studenternas arbete under distansläge. Varje student har också skrivit ett individuellt bidrag där olika områden relaterade till projektet utreds. Bidragen finns i slutet av rapporten.

The aim of this thesis is to create a cloud application for traffic analysis without knowing anything about the system. The only input is address of the web camera pointing at traffic. This application is build on existing solution which is further enhanced. New modules for removing obstacles (such as lamppost covering part of the road) and splitting overlapping cars were added. The whole cloud solution consists of multiple components which communicates by HTTP messages and are controlled by web interface.

Context. As the number of organizations using cloud application platforms to host their applications increases, the priority of distributing physical resources within those platforms is increasing simultaneously. The goal is to host a higher quantity of applications per physical server, while at the same time retain a satisfying rate of performance combined with certain scalability. The modern needs of customers occasionally also imply an assurance of certain privacy for their applications. Objectives. In this study two types of instances for hosting applications in cloud application platforms, virtual machines and application containers, are comparatively analyzed. This investigation has the goal to expose advantages and disadvantages between the instances in order to determine which is more appropriate for being used in cloud application platforms, in terms of performance, scalability and user isolation. Methods. The comparison is done on a server running Linux Ubuntu 16.04. The virtual machine is created using Devstack, a development environment of Openstack, while the application container is hosted by Docker. Each instance is running an apache web server for handling HTTP requests. The comparison is done by using different benchmark tools for different key usage scenarios and simultaneously observing the resource usage in respective instance. Results. The results are produced by investigating the user isolation and resource occupation of respective instance, by examining the file system, active process handling and resource allocation after creation. Benchmark tools are executed locally on respective instance, for a performance comparison of the usage of physical resources. The amount of CPU operations executed within a given time is measured in order determine the processor performance, while the speed of read and write operations to the main memory is measured in order to determine the RAM performance. A file is also transmitted between host server and application in order to compare the network performance between respective instance, by examining the transfer speed of the file. Lastly a set of benchmark tools are executed on the host server to measure the HTTP server request handling performance and scalability of each instance. The amount of requests handled per second is observed, but also the resource usage for the request handling at an increasing rate of served requests and clients. Conclusions. The virtual machine is a better choice for applications where privacy is a higher priority, due to the complete isolation and abstraction from the rest of the physical server. Virtual machines perform better in handling a higher quantity of requests per second, while application containers is faster in transferring files through network. The container requires a significantly lower amount of resources than the virtual machine in order to run and execute tasks, such as responding to HTTP requests. When it comes to scalability the prefered type of instance depends on the priority of key usage scenarios. Virtual machines have quicker response time for HTTP requests but application containers occupy less physical resources, which makes it logically possible to run a higher quantity of containers than virtual machines simultaneously on the same physical server.

Many scholars lament of poor infrastructure to manage and preserve digital records within the public sector in South Africa to support electronic government (egovernment). For example, in South Africa, the national archives’ repository and its subsidiary provincial archives do not have infrastructure to ingest digital records into archival custody. As a result, digital records are left to the creating agencies to manage and preserve. The problem is compounded by the fact that very few public sector organisations in South Africa have procured systems to manage digital records. Therefore, a question is how are digital records managed and stored in these organisations to support e-government? Do public organisations entrust their records to the cloud as an alternative storage given the fact that both physical and virtual storages are a problem? If they do, how do they ensure accessibility, governance, security and long-term preservation of records in the cloud? Utilising the Digital Curation Centre (DCC) Lifecycle Model as a guiding framework, this qualitative study sought to explore digital curation of records in the cloud to support e-government services in South Africa with the view to propose a framework that would guide the public sector to migrate records to the cloud storage. Semi-structured interviews were employed to collect data from the purposively selected Chief Information Officers in the national government departments that have implemented some of the electronic services such as the Department of Arts and Culture, Department of Home Affairs, Department of Higher Education and Training and the Department of Basic Education. Furthermore, the National Archives and Records Services of South Africa was also chosen as it is charged with the statutory regulatory role of records management in governmental bodies. So is the State Information Technology Agency (SITA), a public sector ICT company established in 1999 to consolidate and coordinate the state’s information technology resources in order to achieve cost savings through scale, increase delivery capabilities and enhance interoperability. Interview data were augmented through document analysis of legislation and policies pertaining to data storage. Data were analysed thematically and interpreted in accordance with the objectives of the study. The key finding suggests that although public servants informally and unconsciously put some records in the clouds, government departments in South Africa are sceptical to entrust their records to the cloud due to a number of reasons, such as lack of policy and legislative framework, lack of trust to the cloud storage, jurisdiction, legal implications, privacy, ownership and security risks. This study recommends that given the evolution of technology, the government should regulate cloud storage through policy and legislative promulgation, as well as developing a government-owned cloud managed through SITA in order for all government departments to use it. This study suggests a framework to migrate paperbased records to cloud storage that is controlled by the government. / Information Science / D.Lit. et Phil. (Information Science)