Energy-efficient Communications in Cloud, Mobile Cloud and Fog Computing

This thesis studies the problem of energy efficiency of communications in distributed computing paradigms, including cloud computing, mobile cloud computing and fog/edge computing. Distributed computing paradigms have significantly changed the way of doing business. With cloud computing, companies and end users can access the vast majority services online through a virtualized environment in a pay-as-you-go basis. %Three are the main services typically consumed by cloud users are Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Service (SaaS). Mobile cloud and fog/edge computing are the natural extension of the cloud computing paradigm for mobile and Internet of Things (IoT) devices. Based on offloading, the process of outsourcing computing tasks from mobile devices to the cloud, mobile cloud and fog/edge computing paradigms have become popular techniques to augment the capabilities of the mobile devices and to reduce their battery drain. Being equipped with a number of sensors, the proliferation of mobile and IoT devices has given rise to a new cloud-based paradigm for collecting data, which is called mobile crowdsensing as for proper operation it requires a large number of participants. A plethora of communication technologies is applicable to distributing computing paradigms. For example, cloud data centers typically implement wired technologies while mobile cloud and fog/edge environments exploit wireless technologies such as 3G/4G, WiFi and Bluetooth. Communication technologies directly impact the performance and the energy drain of the system. This Ph.D. thesis analyzes from a global perspective the efficiency in using energy of communications systems in distributed computing paradigms. In particular, the following contributions are proposed: - A new framework of performance metrics for communication systems of cloud computing data centers. The proposed framework allows a fine-grain analysis and comparison of communication systems, processes, and protocols, defining their influence on the performance of cloud applications. - A novel model for the problem of computation offloading, which describes the workflow of mobile applications through a new Directed Acyclic Graph (DAG) technique. This methodology is suitable for IoT devices working in fog computing environments and was used to design an Android application, called TreeGlass, which performs recognition of trees using Google Glass. TreeGlass is evaluated experimentally in different offloading scenarios by measuring battery drain and time of execution as key performance indicators. - In mobile crowdsensing systems, novel performance metrics and a new framework for data acquisition, which exploits a new policy for user recruitment. Performance of the framework are validated through CrowdSenSim, which is a new simulator designed for mobile crowdsensing activities in large scale urban scenarios

Wearable and BAN Sensors for Physical Rehabilitation and eHealth Architectures

The demographic shift of the population towards an increase in the number of elderly citizens, together with the sedentary lifestyle we are adopting, is reflected in the increasingly debilitated physical health of the population. The resulting physical impairments require rehabilitation therapies which may be assisted by the use of wearable sensors or body area network sensors (BANs). The use of novel technology for medical therapies can also contribute to reducing the costs in healthcare systems and decrease patient overflow in medical centers. Sensors are the primary enablers of any wearable medical device, with a central role in eHealth architectures. The accuracy of the acquired data depends on the sensors; hence, when considering wearable and BAN sensing integration, they must be proven to be accurate and reliable solutions. This book is a collection of works focusing on the current state-of-the-art of BANs and wearable sensing devices for physical rehabilitation of impaired or debilitated citizens. The manuscripts that compose this book report on the advances in the research related to different sensing technologies (optical or electronic) and body area network sensors (BANs), their design and implementation, advanced signal processing techniques, and the application of these technologies in areas such as physical rehabilitation, robotics, medical diagnostics, and therapy

ERP implementation methodologies and frameworks: a literature review

Enterprise Resource Planning (ERP) implementation is a complex and vibrant process, one that involves a combination of technological and organizational interactions. Often an ERP implementation project is the single largest IT project that an organization has ever launched and requires a mutual fit of system and organization. Also the concept of an ERP implementation supporting business processes across many different departments is not a generic, rigid and uniform concept and depends on variety of factors. As a result, the issues addressing the ERP implementation process have been one of the major concerns in industry. Therefore ERP implementation receives attention from practitioners and scholars and both, business as well as academic literature is abundant and not always very conclusive or coherent. However, research on ERP systems so far has been mainly focused on diffusion, use and impact issues. Less attention has been given to the methods used during the configuration and the implementation of ERP systems, even though they are commonly used in practice, they still remain largely unexplored and undocumented in Information Systems research. So, the academic relevance of this research is the contribution to the existing body of scientific knowledge. An annotated brief literature review is done in order to evaluate the current state of the existing academic literature. The purpose is to present a systematic overview of relevant ERP implementation methodologies and frameworks as a desire for achieving a better taxonomy of ERP implementation methodologies. This paper is useful to researchers who are interested in ERP implementation methodologies and frameworks. Results will serve as an input for a classification of the existing ERP implementation methodologies and frameworks. Also, this paper aims also at the professional ERP community involved in the process of ERP implementation by promoting a better understanding of ERP implementation methodologies and frameworks, its variety and history

Study of biocompatibility of nanostructured materials on in vitro and in vivo models

Els biomaterials tenen un paper important en la indústria de la salut. Cada any, s'estima que el nombre de dispositius mèdics utilitzats en humans és d'uns 1,5 milions de dispositius individuals, segons l'Organització Mundial de la Salut, amb uns 10.000 tipus de grups de dispositius genèrics disponibles a tot el món. A mesura que sorgeixen nous dispositius, el tema de la biocompatibilitat d'aquests materials es torna més rellevant. Aquesta tesi estudia la biocompatibilitat de biomaterials i la seva interacció amb teixits i cèl·lules combinant models in vitro i in vivo. Els biomaterials estudiats es classifiquen en biomaterials sintètics (polímers, silici, titani i aliatges) i biomaterials derivats de la naturalesa, que al seu torn, es classifiquen en xenogènics, derivats de materials naturals però estranys per a l'organisme i biomaterials autòlegs, derivats dels teixits dels mateixos. organisme. En el cas dels materials sintètics, es va demostrar com les diferents estratègies de funcionalització de les superfícies (en particular, l'efecte del recobriment de proteïnes i la topografia superficial) afecten la resposta de les cèl·lules de mamífer. Els biomaterials autòlegs estaven representats per fibrina rica en plaquetes (PRF), derivada de la sang del pacient.Los biomateriales juegan un papel importante en la industria del cuidado de la salud. Cada año, la cantidad de dispositivos médicos utilizados en humanos se estima en alrededor de 1,5 millones de dispositivos individuales, según la Organización Mundial de la Salud, con alrededor de 10 000 tipos de grupos de dispositivos genéricos disponibles en todo el mundo. A medida que surgen nuevos dispositivos, el tema de la biocompatibilidad de estos materiales se vuelve más relevante. Esta tesis estudia la biocompatibilidad de biomateriales y su interacción con tejidos y células combinando modelos in vitro e in vivo. Los biomateriales estudiados se clasifican en sintéticos (polímeros, silicio, titanio y aleaciones) y biomateriales derivados de la naturaleza, que a su vez, se clasifican en xenogénicos, derivados de materiales naturales pero extraños para el organismo y biomateriales autólogos, derivados de los tejidos del mismo. organismo. En el caso de los materiales sintéticos, se mostró cómo las diferentes estrategias de funcionalización de las superficies (en particular, el efecto del recubrimiento de proteínas y la topografía de la superficie) afectan la respuesta de las células de mamíferos. Los biomateriales autólogos estuvieron representados por fibrina rica en plaquetas (PRF), derivada de la sangre del paciente.Biomaterials play a substantial role in the health care industry. Each year, the number of medical devices used in humans is estimated to be around 1.5 million individual devices, according to the World Health Organization, with about 10 000 types of generic device groups available worldwide. As new devices emerge, the topic of the biocompatibility of these materials becomes more relevant. This thesis studies biocompatibility of biomaterials and their interaction with tissues and cells combining in vitro and in vivo models. The studied biomaterials are classified in synthetic (polymers, silicon, titanium and alloys) and nature-derived biomaterials, which in turn, classify in xenogenic, derived from natural materials but foreign for the organism and autologous biomaterials, derived from the tissues of the same organism. In the case of synthetic materials, it was shown how different functionalization strategies of surfaces (in particular, the effect of protein coating and surface topography) affect mammalian cell response. Autologous biomaterials were represented by platelet rich fibrin (PRF), derived from the blood of the patient. Their potential as implantable system was studied in vitro and in vivo

Business process modelling in ERP implementation literature review

Business processes are the backbone of any Enterprise Resource Planning (ERP) implementation. Business process modelling (BPM) has become essential for modern, process driven enterprises due to the vibrant business environments. As a consequence enterprises are dealing with a substantial rate of organizational and business processes change. Business process modelling enables a common understanding and analysis of the business processes, which is the first step in every ERP implementation methodology (blueprint phase). In order to represent enterprise processes models in an accurate manner, it is paramount to choose a right business process modeling technique and tool. The problem of many ERP projects rated as unsuccessful is directly connected to a lack of use of business process models and notations during the blueprint phase. Also, blueprint implementation phase is crucial in order to fit planned processes in an organization with processes implemented in the solution. However, business analysts and ERP implementation professionals have substantial difficulties to navigate through a large number of theoretical models and representational notations that have been proposed for business process modeling (BPM). As the availability of different business process modeling references is huge, it is time consuming to make review and classification of all modeling techniques. Therefor, in reality majority of ERP implementations blueprint documents have no business process modeling included in generating blueprint documents. Choosing the right model comprise the purpose of the analysis and acquaintance of the available process modelling techniques and tools. The number of references on business modelling is quit large, so it is very hard to make a decision which modeling notation or technique to use. The main purpose of this paper is to make a review of business process modelling literature and describe the key process modelling techniques. The focus will be on all business process modeling that could be used in ERP implementations, specifically during the blueprint phase of the implementation process. Detailed review of BPM (Business process modeling) theoretical models and representational notations, should assist decision makers and ERP integrators in comparatively evaluating and selecting suitable modeling approaches

A conceptual framework for capability sourcing modeling

Companies need to acquire the right capabilities from the right source, and the right shore, at the right cost to improve their competitive position. Capability sourcing is an organizing process to gain access to best-in-class capabilities for all activities in a firm's value chain to ensure long-term competitive advantage. Capability sourcing modeling is a technique that helps investigating sourcing alternative solutions to facilitate strategic sourcing decision making. Our position is applying conceptual models as intermediate artifacts which are schematic descriptions of sourcing alternatives based on organization's capabilities. The contribution of this paper is introducing a conceptual framework in the form of five views (to organize all perspectives) and a conceptualisation (to formulate a language) for capability sourcing modelling

The creation of business architecture heat maps to support strategy-aligned organizational decisions

The realization of strategic alignment within the business architecture has become increasingly important for companies. Indeed, it facilitates business-IT alignment as a well-designed business architecture helps both to identify the appropriate requirements for IT systems and to discover new business opportunities that can be realized by IT. However, there is a lack of alignment techniques that support organizational (re) design decisions during the operation phase as the actual performance of business architecture elements is neglected. Capability heat maps provide a useful starting point in this respect as they focus on the creation of a hierarchy of prioritized capabilities, which are characterized by a performance measure. In this paper, these techniques will be extended to support strategy-aligned decisions within the business architecture. The identification of the relevant business architecture elements is based on state-of-the-art enterprise modelling languages, which enable the development of enterprise models on distinct layers of the business architecture. Strategic alignment between these elements will be realized by using prioritization according to the Analytic Hierarchy Process (AHP), while performance measurement will enable the creation of a proper decision support system. Afterwards, the proposed heat map will be applied on a case example to illustrate its potential use. This results in the completion of a first build-and-evaluate loop within the Design Science methodology

From strategy to operations and vice-versa: a bridge that needs an Island

The Information Systems support particularly for Tactical Management is not an explicit or distinct term. There are many concepts and artifacts that are providing contemporary foundations for Information systems in the companies, both in theory and in practice. We tried to analyze different approaches, in order to determine their support specifically for tactical management. Out of this attempt, the realization is that these seemingly overarching bridges from Operations to Strategy and vice-versa appear to be overshooting an important island - the tactical management level, particularly in recognizing its distinct characteristics to be served with adjusted concepts and solutions. We see tactical management as the managerial function that implements strategies, by deploying and utilizing specific resources from the operational level in order to gain that specific competitive advantage prescribed in the strategy. The diversity of approaches and tools is provided for the strategic and overwhelmingly for operational management issues. This theoretical research is analyzing the specifics of the Sense-and-Respond Framework on a tactical level towards perfecting the sensing part of it (in terms of sustaining "low latency" (instead of operational "no latency") and striving for tactical need for "right-time" (instead of the current and hot operational "real-time") information), and how it is being closed in theory and practice on a strategic, tactical and operational level with 'endings'. Also, the tactical management characteristic of working in unpredicted environment and needing high adaptability, requires involvement of concepts and approaches that provide adaptability such as, in our opinion, the Sense-and-Respond managerial concept and the SIDA loop. To some extent, tactical management is being assimilated either by strategy or by operations, as this research confirms. Hopefully, we will result with increased perceptiveness that tactical management needs special theoretical and practical focus and output propositions. The specific sensing and interpreting, deciding and acting, in the role of a tactical manager is neither only automatic, data-capturing process nor a person-independent or company-independent one. If, and after this viewpoint is shared, much more efforts will be streamlined in the tactical management "how" to do "what" is expected, on theoretical and on practical level