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Tesis por compendio / [EN] Modern data centers integrate a lot of computer and electronic devices. However, some reports state that the mean usage of a typical data center is around 50% of its peak capacity, and the mean usage of each server is between 10% and 50%. A lot of energy is destined to power on computer hardware that most of the time remains idle. Therefore, it would be possible to save energy simply by powering off those parts from the data center that are not actually used, and powering them on again as they are needed. Most data centers have computing clusters that are used for intensive computing, recently evolving towards an on-premises Cloud service model. Despite the use of low consuming components, higher energy savings can be achieved by dynamically adapting the system to the actual workload. The main approach in this case is the usage of energy saving criteria for scheduling the jobs or the virtual machines into the working nodes. The aim is to power off idle servers automatically. But it is necessary to schedule the power management of the servers in order to minimize the impact on the end users and their applications. The objective of this thesis is the elastic and efficient management of cluster infrastructures, with the aim of reducing the costs associated to idle components. This objective is addressed by automating the power management of the working nodes in a computing cluster, and also proactive stimulating the load distribution to achieve idle resources that could be powered off by means of memory overcommitment and live migration of virtual machines. Moreover, this automation is of interest for virtual clusters, as they also suffer from the same problems. While in physical clusters idle working nodes waste energy, in the case of virtual clusters that are built from virtual machines, the idle working nodes can waste money in commercial Clouds or computational resources in an on-premises Cloud. / [ES] En los Centros de Procesos de Datos (CPD) existe una gran concentración de dispositivos informáticos y de equipamiento electrónico. Sin embargo, algunos estudios han mostrado que la utilización media de los CPD está en torno al 50%, y que la utilización media de los servidores se encuentra entre el 10% y el 50%. Estos datos evidencian que existe una gran cantidad de energía destinada a alimentar equipamiento ocioso, y que podríamos conseguir un ahorro energético simplemente apagando los componentes que no se estén utilizando. En muchos CPD suele haber clusters de computadores que se utilizan para computación de altas prestaciones y para la creación de Clouds privados. Si bien se ha tratado de ahorrar energía utilizando componentes de bajo consumo, también es posible conseguirlo adaptando los sistemas a la carga de trabajo en cada momento. En los últimos años han surgido trabajos que investigan la aplicación de criterios energéticos a la hora de seleccionar en qué servidor, de entre los que forman un cluster, se debe ejecutar un trabajo o alojar una máquina virtual. En muchos casos se trata de conseguir equipos ociosos que puedan ser apagados, pero habitualmente se asume que dicho apagado se hace de forma automática, y que los equipos se encienden de nuevo cuando son necesarios. Sin embargo, es necesario hacer una planificación de encendido y apagado de máquinas para minimizar el impacto en el usuario final. En esta tesis nos planteamos la gestión elástica y eficiente de infrastructuras de cálculo tipo cluster, con el objetivo de reducir los costes asociados a los componentes ociosos. Para abordar este problema nos planteamos la automatización del encendido y apagado de máquinas en los clusters, así como la aplicación de técnicas de migración en vivo y de sobreaprovisionamiento de memoria para estimular la obtención de equipos ociosos que puedan ser apagados. Además, esta automatización es de interés para los clusters virtuales, puesto que también sufren el problema de los componentes ociosos, sólo que en este caso están compuestos por, en lugar de equipos físicos que gastan energía, por máquinas virtuales que gastan dinero en un proveedor Cloud comercial o recursos en un Cloud privado. / [CA] En els Centres de Processament de Dades (CPD) hi ha una gran concentració de dispositius informàtics i d'equipament electrònic. No obstant això, alguns estudis han mostrat que la utilització mitjana dels CPD està entorn del 50%, i que la utilització mitjana dels servidors es troba entre el 10% i el 50%. Estes dades evidencien que hi ha una gran quantitat d'energia destinada a alimentar equipament ociós, i que podríem aconseguir un estalvi energètic simplement apagant els components que no s'estiguen utilitzant. En molts CPD sol haver-hi clusters de computadors que s'utilitzen per a computació d'altes prestacions i per a la creació de Clouds privats. Si bé s'ha tractat d'estalviar energia utilitzant components de baix consum, també és possible aconseguir-ho adaptant els sistemes a la càrrega de treball en cada moment. En els últims anys han sorgit treballs que investiguen l'aplicació de criteris energètics a l'hora de seleccionar en quin servidor, d'entre els que formen un cluster, s'ha d'executar un treball o allotjar una màquina virtual. En molts casos es tracta d'aconseguir equips ociosos que puguen ser apagats, però habitualment s'assumix que l'apagat es fa de forma automàtica, i que els equips s'encenen novament quan són necessaris. No obstant això, és necessari fer una planificació d'encesa i apagat de màquines per a minimitzar l'impacte en l'usuari final. En esta tesi ens plantegem la gestió elàstica i eficient d'infrastructuras de càlcul tipus cluster, amb l'objectiu de reduir els costos associats als components ociosos. Per a abordar este problema ens plantegem l'automatització de l'encesa i apagat de màquines en els clusters, així com l'aplicació de tècniques de migració en viu i de sobreaprovisionament de memòria per a estimular l'obtenció d'equips ociosos que puguen ser apagats. A més, esta automatització és d'interés per als clusters virtuals, ja que també patixen el problema dels components ociosos, encara que en este cas estan compostos per, en compte d'equips físics que gasten energia, per màquines virtuals que gasten diners en un proveïdor Cloud comercial o recursos en un Cloud privat. / Alfonso Laguna, CD. (2015). Efficient and elastic management of computing infrastructures [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/57187 / Compendio

The transition towards sustainable energy in the construction machinery sector is gaining momentum due to the urgent need to reduce greenhouse gas emissions and operational costs. Despite the benefits of electric construction machinery, challenges such as high initial investment costs, infrastructure requirements, and the practicality of battery swapping systems hinder widespread adoption. Understanding the economic feasibility and practical implications of implementing battery swapping in different construction scenarios is crucial for facilitating this transition. This study contributes to the existing body of knowledge by conducting a detailed Total Cost of Ownership (TCO) analysis for various energy sources —diesel, built-in batteries, and battery swapping systems — in two distinct construction settings: Big Quarry and Small Construction site. It provides a comparative evaluation of these options, highlighting the economic and environmental benefits of battery swapping. A comprehensive TCO analysis was performed, encompassing costs related to machine purchase, fuel/electricity consumption, maintenance, and infrastructure. Sensitivity analyses were conducted to identify critical cost drivers and assess the impact of fluctuating fuel and battery prices on the overall cost-effectiveness of each energy solution.  The findings indicate that battery swapping is the most cost-effective option across both construction sites, offering substantial savings compared to diesel and built-in batteries. Sensitivity analyses further showed that even with increased battery costs, electric machinery maintained stable economic performance, underscoring its viability as a sustainable alternative.

Bakgrund: I och med den ständiga utvecklingen beträffande hanteringen av internaprocesser har automatisering av aktiviteter för lager- och materialhantering ökat. Maskiner som verkar automatiskt benämns som Automated Guided Vehicles, vilket förkortas AGV, därdess utökade användningsområde inom interna processer har ökat avsevärt. Innebörden av AGV-system har genererat omfattande förbättringar av prestanda, däribland produktivitetsförbättringar. Grunden till produktivitetsförbättringarna innefattas av aspektersom att reducering av flaskhalsar samt att nedskärning vid beroende av mänsklig hantering. Syfte: Uppsatsens syfte är att studera möjligheter och utmaningar avseende om det är aktuellt för Atea Logistics AB med en implementering av ett AGV-system för interna processer ideras internlogistikområde. Därutöver är syftet att analysera och presentera vilka förutsättningar som kan påverka lönsamheten för en distributör vid en implementering av ett AGV-system för interna processer i verksamhetens interna logistikområde. Metod: Metodvalen i studien grundar sig i ett kvalitativt tillvägagångssätt till studiensinledande forskningsfråga. Därefter har en kvantitativ forskningsmetod applicerats för att tillämpa uppsatsens andra forskningsfråga. Med avsikt att erhålla en bred omfattning beträffande datainsamlingen har både primär- respektive sekundärdata inhämtats. För att skapa ett välgrundat resultat har det teoretiska materialet studerats i förhållande till det empiriska underlaget. Resultat: Baserat på ett flertal variabler för prestanda diskuteras implementeringen av ett AGV-system hos Atea utifrån lönsamhet. Resultatet visade att det finns flera utmaningar samt möjligheter vid genomförandet av implementeringen, dock visar slutsatsen att det inte är genomförbart för Atea att implementera ett AGV-system med de resurser de har i nuläget. Med utgångspunkt i att studera lönsamheten för liknande distributionsföretag beträffande implementering av ett AGV-system visade det att variabler i form av lönekostnader,investeringskostnaden, transporttid för bingar och väntetid är aspekter som är nödvändigt att ta i beaktning vid investeringen. / Background: With the constant evolution of the management of internal processes, the automation of warehouse and material handling activities has increased. Machines that operate automatically are referred to as Automated Guided Vehicles, abbreviated as AGVs, where their extended use in internal processes has increased significantly. The adoption of AGV systems has generated widespread improvements in performance, including productivity improvements. The basis for productivity improvements includes aspects such as reducing bottlenecks and cutting dependence on human handling.  Purpose: The purpose of the thesis is to study opportunities and challenges regarding whether it is relevant for Atea Logistics AB to implement an AGV system for internal processes in their internal logistics area. In addition, the purpose is to analyze and present the conditions that can affect the profitability of a distributor when implementing an AGV system for internal processes in the company's internal logistics area.  Method: The basis for the methodological choices of the study relates to a qualitative approach to the initial research question of the study. Subsequently, a quantitative research method has been applied to address the second research question of the paper. In order to obtain a broad scope of data collection, both primary and secondary data have been collected. In order to create a well-founded result, the theoretical material has been studied in relation to the empirical data.  Results: Based on several performance variables, the implementation of an AGV-system at Atea is discussed in terms of profitability. The results revealed several challenges and opportunities associated with the implementation. However, the conclusion is that it is not profitable for Atea to implement an AGV-system with the resources they have today.  Based on studying the profitability of similar distribution companies regarding the implementation of an AGV-system, it was found that variables such as labor costs, investment costs, bin transport time and waiting time are aspects that are crucial to consider regarding the investment.

L’objectif de ces travaux est de développer une méthode d’aide à la conception des réseaux de chaleur urbains (RCU). Cette méthode utilise un modèle de type MINLP (Mixed Integer Non Linear Programming) pour l’optimisation simultanée de la configuration et du dimensionnement d’un RCU. Aux variables continues pour l’aide au dimensionnement (température, vitesse, diamètre, aire des échangeurs), s’ajoutent des variables binaires aidant à définir la configuration du réseau (maillage et choix des technologies). La fonction objectif à minimiser est le coût total (capex et opex), qui est soumise à un ensemble de contraintes non linéaires (p. ex. pertes thermiques et de charge, bilans). La méthode développée dans ce manuscrit offre la possibilité de connecter en cascade des consommateurs n’ayant pas les mêmes besoins en température, et de réaliser des réseaux bouclés (une canalisation par tranchée). Elle permet aussi de choisir : les consommateurs à connecter au RCU, le ou les sites de production ainsi que le type de technologie utilisée. Enfin la bonne prise en compte de la physique permet de choisir le meilleur compromis entre pertes thermiques et pertes de charge, sur une large gamme de température. Cette formulation permet donc d’optimiser des réseaux de 4éme génération et de démontrer la rentabilité de l’intégration d’EnR&R sur le long terme (30 ans). Un premier travail est réalisé afin de proposer une méthodologie de résolution en plusieurs étapes permettant l’obtention de l’optimum global. Différents cas d’études académiques sont utilisés pour présenter les intérêts multiples de cette formulation. Enfin la comparaison avec un réseau existant a permis de démontrer la cohérence des résultats du modèle et a servi de base pour l’optimisation d’un cas d’étude de grande dimension. Plusieurs études de sensibilité post-optimale sont réalisées afin de démontrer l’intérêt de cet outil pour l’aide à la conception initiale ou l’extension de RCU existants. / The aim of this thesis is to develop a method that provides design assistance for District Heating Network (DHN). This tool allows simultaneously the optimization of the configuration and its sizing, thanks to an MINLP formulation (Mixed Integer Non-Linear Programming). Binary variables help to choose the optimal configuration (network layout and technologies of production), whereas continuous variables help DHN sizing (temperature, diameter, velocity, heat exchanger area, thermal generating capacity …). The objective function to minimize is the total cost (capex and opex), subjected to numerous nonlinear constraints (e.g. thermal losses, pressure drop, energy balance).This method enables to design temperature cascade between consumers, when consumer temperature requirements are different, and also looped network (only one pipe in one trench). It helps also the decision to connect (or not) consumers to the main network and also the location(s) and type(s) of the heating plant. Moreover, the arbitrage between heat losses and pressure drops is taken into account thanks to physical considerations (non-linear equations). Eventually, it is possible to design 4th generation DHN and prove their financial profitability over the long terms (30 years). First a multi-step resolution strategy is proposed to ensure finding global optimum of the complex MINLP problem. Then academic study cases are analyzed to underline the numerous assets of the formulation. Finally, the optimal design compared to an existing DHN ensures the consistency of the method and allows to build a study case at a wider scale, which can be solved thanks to the comprehensive strategy developed. The design assistance method is available for initial design as well as for extension of existing DHN.

<p>Cardo AB is an international corporate group that has performed major organizational changes the last few years. These changes utilize possible synergies that exist in a corporate group. One of the initiatives is that Cardo wants to develop a model for make-or-buy decisions. Therefore, the purpose of this thesis is stated as:</p><p><em>The study’s purpose is to develop a generic model for make-or-buy decisions at Cardo.</em></p><p>To develop the model, a theoretical study was conducted, where four main aspects were identified: core capability, risk, cost and relationship. For each aspect, a tool to define what the aspects consist of was identified. The aspects were combined together into a model, called model version 1. To enhance and adjust the model to suit Cardo’s situation, an empirical study was conducted. In the empirical study, it was investigated how different sites within Cardo are currently working with make-or-buy decisions. Moreover, in the empirical study it was also revealed how Cardo is dealing with each of the aspects identified in theory. The combination of theory and empirical study formed the enhanced model, called model version 2. The last step in the procedure was to let several end-users review the model and suggest improvements. After this step, the final model was formed, called model version 3.The model combines the best practices from Cardo with the latest theoretical aspects. Using this model will help Cardo deal with make-or-buy decisions in a structured way. The model highlights the importance of connecting business strategy with the core capabilities of Cardo and provides a tool to identify this connection. Furthermore, the model highlights risks connected to outsourcing and provides tools to identify these risks. The model also applies a total cost approach. To calculate the different costs, a model is presented that functions as a guide when quantifying costs. Lastly, the model shows the importance of developing a proper relationship with the supplier according to the strategic importance of the product.Cardo AB is an international corporate group that has performed major organizational changes the last few years. These changes utilize possible synergies that exist in a corporate group. One of the initiatives is that Cardo wants to develop a model for make-or-buy decisions. Therefore, the purpose of this thesis is stated as:The study’s purpose is to develop a generic model for make-or-buy decisions at Cardo.To develop the model, a theoretical study was conducted, where four main aspects were identified: core capability, risk, cost and relationship. For each aspect, a tool to define what the aspects consist of was identified. The aspects were combined together into a model, called model version 1. To enhance and adjust the model to suit Cardo’s situation, an empirical study was conducted. In the empirical study, it was investigated how different sites within Cardo are currently working with make-or-buy decisions. Moreover, in the empirical study it was also revealed how Cardo is dealing with each of the aspects identified in theory. The combination of theory and empirical study formed the enhanced model, called model version 2. The last step in the procedure was to let several end-users review the model and suggest improvements. After this step, the final model was formed, called model version 3.The model combines the best practices from Cardo with the latest theoretical aspects. Using this model will help Cardo deal with make-or-buy decisions in a structured way. The model highlights the importance of connecting business strategy with the core capabilities of Cardo and provides a tool to identify this connection. Furthermore, the model highlights risks connected to outsourcing and provides tools to identify these risks. The model also applies a total cost approach. To calculate the different costs, a model is presented that functions as a guide when quantifying costs. Lastly, the model shows the importance of developing a proper relationship with the supplier according to the strategic importance of the product.</p>

Cardo AB is an international corporate group that has performed major organizational changes the last few years. These changes utilize possible synergies that exist in a corporate group. One of the initiatives is that Cardo wants to develop a model for make-or-buy decisions. Therefore, the purpose of this thesis is stated as: The study’s purpose is to develop a generic model for make-or-buy decisions at Cardo. To develop the model, a theoretical study was conducted, where four main aspects were identified: core capability, risk, cost and relationship. For each aspect, a tool to define what the aspects consist of was identified. The aspects were combined together into a model, called model version 1. To enhance and adjust the model to suit Cardo’s situation, an empirical study was conducted. In the empirical study, it was investigated how different sites within Cardo are currently working with make-or-buy decisions. Moreover, in the empirical study it was also revealed how Cardo is dealing with each of the aspects identified in theory. The combination of theory and empirical study formed the enhanced model, called model version 2. The last step in the procedure was to let several end-users review the model and suggest improvements. After this step, the final model was formed, called model version 3.The model combines the best practices from Cardo with the latest theoretical aspects. Using this model will help Cardo deal with make-or-buy decisions in a structured way. The model highlights the importance of connecting business strategy with the core capabilities of Cardo and provides a tool to identify this connection. Furthermore, the model highlights risks connected to outsourcing and provides tools to identify these risks. The model also applies a total cost approach. To calculate the different costs, a model is presented that functions as a guide when quantifying costs. Lastly, the model shows the importance of developing a proper relationship with the supplier according to the strategic importance of the product.Cardo AB is an international corporate group that has performed major organizational changes the last few years. These changes utilize possible synergies that exist in a corporate group. One of the initiatives is that Cardo wants to develop a model for make-or-buy decisions. Therefore, the purpose of this thesis is stated as:The study’s purpose is to develop a generic model for make-or-buy decisions at Cardo.To develop the model, a theoretical study was conducted, where four main aspects were identified: core capability, risk, cost and relationship. For each aspect, a tool to define what the aspects consist of was identified. The aspects were combined together into a model, called model version 1. To enhance and adjust the model to suit Cardo’s situation, an empirical study was conducted. In the empirical study, it was investigated how different sites within Cardo are currently working with make-or-buy decisions. Moreover, in the empirical study it was also revealed how Cardo is dealing with each of the aspects identified in theory. The combination of theory and empirical study formed the enhanced model, called model version 2. The last step in the procedure was to let several end-users review the model and suggest improvements. After this step, the final model was formed, called model version 3.The model combines the best practices from Cardo with the latest theoretical aspects. Using this model will help Cardo deal with make-or-buy decisions in a structured way. The model highlights the importance of connecting business strategy with the core capabilities of Cardo and provides a tool to identify this connection. Furthermore, the model highlights risks connected to outsourcing and provides tools to identify these risks. The model also applies a total cost approach. To calculate the different costs, a model is presented that functions as a guide when quantifying costs. Lastly, the model shows the importance of developing a proper relationship with the supplier according to the strategic importance of the product.

This work reports on virtualization and cloud computing technologies. It evaluates their strengths and weaknesses as well as describes the examples of its deployment. The document serves as a concise and comprehensive guide, describing the necessary theory along with the practical use. It is all demonstrated on a real project. The practical part refers to the data environment of the Fire Rescue Service of South Bohemia Region and represents the usage of studied technologies. The analysis also includes project´s financial and technical aspects.

Within a production machine, various electromechanical and pneumatic structures can be used for drive tasks. As these drive technologies can often replace each other, the energy efficiency, performance and TCO of pneumatic drives must be permanently enhanced to remain competitive. There is a large number of known measures for the reducing their energy consumption, e.g. minimizing of filling volumes, energy saving circuits etc. However, these measures are mainly considered separately and the possible overall energy saving effect resulting from their combination is rarely taken into account. The main goal of this paper is therefore to explore the possible combinations of pneumatic energy saving measures and their cumulative saving effect. Due to the fact that some measures are mutually exclusive (e.g. a general pressure reduction in properly sized drive), each combination should be considered separately. To evaluate their efficiency plausibly, a comprehensive assessment is required that contains both the total cost of ownership analysis (TCO) and a mechanical properties assessment. The presented comprehensive approach of the task analysis can serve as example of how an optimal drive configuration for the specific task can be found, thus creating a basis for solving constructive challenges in designing of pneumatic automation systems.

Cloud computing is a technology that has gained increasing attention because of its considerable benefits, which include reduced costs, reduced complexity and increased flexibility. To obtain these benefits, cloud computing utilizes existing technologies, such as grid computing, virtualization and web services, for online delivery of scalable information technology (IT) services, frequently on the basis of a pay-per-use pricing model. In 2008, the Gartner Group predicted that cloud computing would reach the mainstream within two to five years. However, in their latest hype cycle for emerging technologies, they stated that cloud computing had not yet reached the plateau of productivity but rather was still in the trough of disillusionment. The reason for this situation may be that cloud computing continues to face skepticism because of various concerns regarding, e.g., data privacy and security. In particular, (enterprise) customers transfer (sensitive) data to cloud computing providers, and the end-user rents the right to use cloud computing services via a web browser with minimal need to interact or even without the necessity of interacting directly with a sales assistant. These two aspects result in a strong unilateral dependency and require a high degree of trust in the provider. Additionally, publicity regarding the PRISM program has brought these aspects to the forefront of public interest. Consequently, specific requirements regarding, e.g., security, privacy, accountability, and auditability, must be met to fulfill the expectations of business partners and to build long-term business relationships. Thus, overcoming information asymmetry, enhancing transparency and eradicating behavioral uncertainty is of high importance to build trust between cloud computing providers and their (prospective) customers. Therefore, although most research to date has focused on technical aspects and aimed to improve the actual security of cloud computing services, there is also an urgent need to understand the factors that affect the adoption of cloud computing services from the points of view of both private users and companies. If cloud computing is to reach its full potential, a clear understanding of the factors that influence its adoption is mandatory to improve both present and future cloud computing services. Motivated by these considerations, the aim of this doctoral thesis is to explore, describe, analyze and explain the factors that influence the adoption of cloud computing using various qualitative and quantitative research methods, i.e., by employing a mixed-methods analysis. As a first step, a serious game is conducted to explore various factors that influence the adoption of cloud computing services. Based on these initial findings, the factors explored during the serious game and some additional factors are described and analyzed in detail. These factors include the cloud computing market, costs, trust, affectedness, shadow IT, and sustainability. Furthermore, the factor of information asymmetry, especially regarding bridging the information asymmetry with various information presentation methods, is explained. Following these findings, a research agenda, which contains a recommended research design and lists the theories that are relevant in the context of the adoption of cloud computing, is proposed. Subsequently, a synthesis of the research findings in terms of their implications for practice and research, including limitations, are discussed.