Cost-effective Information and Communication Technology (ICT) infrastructure for Tanziania

The research conducted an Information and Communication Technology (ICT) field survey, the results revealed that Tanzania is still lagging behind in the ICT sector due to the lack of an internationally connected terrestrial ICT infrastructure; Internet connectivity to the rest of the world is via expensive satellite links, thus leaving the majority of the population unable to access the Internet services due to its high cost. Therefore, an ICT backbone infrastructure is designed that exploits optical DWDM network technology, which un-locks bandwidth bottlenecks and provides higher capacity which will provide ICT services such as Internet, voice, videos and other multimedia interactions at an affordable cost to the majority of the people who live in the urban and rural areas of Tanzania. The research analyses and compares the performance, and system impairments, in a DWDM system at data transmission rates of 2.5 Gb/s and 10 Gb/s per wavelength channel. The simulation results show that a data transmission rate of 2.5 Gb/s can be successfully transmitted over a greater distance than 10 Gb/s with minimum system impairments. Also operating at the lower data rate delivers a good system performance for the required ICT services. A forty-channel DWDM system will provide a bandwidth of 100 Gb/s. A cost analysis demonstrates the economic worth of incorporating existing optical fibre installations into an optical DWDM network for the creation of an affordable ICT backbone infrastructure; this approach is compared with building a completely new optical fibre DWDM network or a SONET/SDH network. The results show that the ICT backbone infrastructure built with existing SSMF DWDM network technology is a good investment, in terms of profitability, even if the Internet charges are reduced to half current rates. The case for building a completely new optical fibre DWDM network or a SONET/SDH network is difficult to justify using current financial data

Selected Topics on Computed Tomography

This book is a research publication that covers developments within the Diagnostics field of study. The book is a collection of reviewed scholarly contributions written by different authors and edited by an expert with specific expertise. Each scholarly contribution represents a chapter which is complete in itself but related to the major topics and objectives. The target audience comprises scholars and specialists in the field

Modelling, Dimensioning and Optimization of 5G Communication Networks, Resources and Services

This reprint aims to collect state-of-the-art research contributions that address challenges in the emerging 5G networks design, dimensioning and optimization. Designing, dimensioning and optimization of communication networks resources and services have been an inseparable part of telecom network development. The latter must convey a large volume of traffic, providing service to traffic streams with highly differentiated requirements in terms of bit-rate and service time, required quality of service and quality of experience parameters. Such a communication infrastructure presents many important challenges, such as the study of necessary multi-layer cooperation, new protocols, performance evaluation of different network parts, low layer network design, network management and security issues, and new technologies in general, which will be discussed in this book

Planning and Design for Intelligent and Secure Integration of Electric Vehicles into the Smart Grid

The transition to electric vehicles (EVs) is gaining momentum around the world and government initiatives to accelerate this transition range from major tax exemptions, lower insurance payments to convenient parking incentives at shopping malls. The major drivers for this acceleration are the rising awareness by the public for maintaining a clean environment, reducing pollutant emissions, breaking dependencies on oil, as well as tapping into cleaner sources of energies. EVs acceptance however is hindered by several challenges; among them is their shorter driving range, slower charging rates, and the ubiquitous availability of charging locations, collectively contributing to higher anxieties for EVs drivers. Governments of developed countries as well as major car manufacturers are taking solid steps to address these challenges and set ambitious goals to make EVs the major transportation mode within few years. Consequently, a significant number of EVs is going to connect to the existing smart grid and hence, the load pattern is expecting a paradigm shift. This immense load will challenge the generation, transmission and distribution sector of the grid along with being a potential cyber-physical attack platform. To attain a graceful EV penetration for curtailing GHG emission, along with the socioeconomic initiatives, an extensive research is required, especially to mitigate the range anxiety and ameliorate the load congestion on the grid. As a consequence, to reduce the range anxiety, we present a two-stage solution to provision and dimension a DC fast charging station (CS) network for the anticipated energy demand and that minimizes the deployment cost while ensuring a certain quality of experience for charging e.g., acceptable waiting times and shorter travel distances to charge. This solution also maintains the voltage stability by considering the distribution grid capacity, determining transformers’ rating to support peak demand of EV charging and adding a minimum number of voltage regulators based on the impact over the power distribution network. We propose, evaluate and compare two CS network expansion models to determine a cost-effective and adaptive CSs provisioning solution that can efficiently expand the CS network to accommodate future EV charging and conventional load demands. Though an adequate fast charging network may assist to reduce the range anxiety and propel the EV market, catering this large number of EVs using fuel based conventional grid actually shifts the carbon footprint from the transportation sector to the power generation sector. As a consequence, green energy needs to be promoted for EV charging. However, the intermittent behavior of renewable energy (RE) generation challenges to maintain a RE based stand alone CS. In order to address this issue, we consider a photovoltaic(PV) powered station equipped with an energy storage system (ESS), which is assumed to be capable of assigning variable charging rates to different EVs to fulfill their demands inside their declared deadlines at minimum price. To ensure fairness, a charging rate dependent pricing mechanism is proposed to assure a higher price for enjoying a higher charging rate. The PV generation profile and future load request are forecasted at each time slot, to handle the respective uncertainties. Whatever, the energy source is green or not of a CS, a static CS cannot offer the flexibility to charge an EV at any place at any time especially for an emergency case. Fortunately, the bidirectional energy transferring capability between vehicles (i.e., vehicle to vehicle (V2V)) might be a solution to charge an EV at any place and at any time without leaning on a stationary CS. Hence, we assume a market where charging providers each has a number of charging trucks equipped with a larger battery and a fast charger to charge a number of EVs at some particular parking lots. We formulate an integer linear program (ILP) to maximize the number of served EVs by determining the optimal trajectory and schedule of each truck. Owing to its complexity, we implement Dantzig-Wolfe decomposition approach to solve this. However, to build a prolific EV charging ecosystem, all its entities (e.g., EVs, CSs and grid) have to be connected through a communication link and that unveils a new cyber physical attack surface. As a consequence, we exploit the abundance of Electric Vehicles (EVs) to target the stability of the power grid by presenting a realistic coordinated switching attack that initiates inter-area oscillations between different areas of the power grid and assess the dire consequences over the power system. Finally, a back propagation neural network (BPNN) technique is used in a proposed framework to detect such switching attacks before being executed

Cost-Effective and Optimized Optical Networks Based on Point to Multipoint Transceivers

The rapid increase in internet traffic due to widespread internet access and technological advancements such as 5G, cloud omputing, Internet of Things (IoT), and virtual reality has created a complex environment for network operators and internet service providers. To ensure profitability and improve user experience, these entities need to implement long-term strategies that optimize network planning, cost, and efficiency. These strategies should consider market demands, evolving technologies, and prioritize resource utilization, customer expansion, service quality, and cost reduction. The thesis mainly focuses on network design and optimization. It begins with a concise introduction to optical transport network elements and the primary motivations for networking. The use of dense wavelength division multiplexing (DWDM) systems is described, along with the conventional network problems associated with routing and wavelength assignment, as well as routing and spectrum assignment. The thesis also includes a brief discussion on the power consumption of the Internet, with a particular focus on routers as power-hungry network components. Next, the thesis delves into the digital subcarrier multiplexing point-to-multipoint (P2MP) transceiver, explaining its architecture and function. Several optimization frameworks based on integer linear Programming (ILP) are proposed to effectively deploy P2MP transceivers in both filtered and filterless scenarios. Different protection scenarios are also explored. Furthermore, the thesis investigates a comprehensive multi-period planning scenarios that take into account evolving traffic and transceiver technology. The results demonstrate that P2MP transceivers can reduce transceiver costs by up to 35% compared to traditional point-to-point transceivers. Finally, the thesis presents a comprehensive and optimized physical design for horseshoe networks, integrating the utilization of P2MP transceivers and a filterless architecture. This design approach offers a simplified and cost-effective solution while leveraging the savingsoffered by P2MP technology

Charging Model Development For Data Center Network Environment

Tämän diplomityön tarkoituksena on tutkia, kuinka organisaatio voi kehittää ja järjestää verkkopalveluiden veloituskäytäntöjä datakeskusympäristössä. Työn teoriaosuus esittelee työn kannalta keskeiset konseptit sekä niiden ominaispiirteet. Empiirisessä osuudessa kartoitetaan nykytilanteen haasteet ja verrattaan niitä yleisiin käytäntöihin. Kartoituksen pohjalta luodaan suunnitelma ja kehitysehdotukset veloituskäytäntöjen kehittämiseksi. Työn teoriaosuudessa esitellään tutkimuskysymyksen kannalta relevantit konseptit. Ensiksi käydään läpi palvelunhallintakäytäntöjä pohjaten ITIL -prosesseihin. Tämän jälkeen perehdytään datakeskusympäristön kannalta oleellisiin verkkopalveluiden piirteisiin. Lopuksi esitellään verkkopalveluihin liittyviä ekonomisia malleja. Esiteltävät mallit liittyvät kustannusten allokointiin, hinnoitteluun ja veloituskäytäntöihin. Työn empiirisessä osiossa pyritään tunnistamaan organisaation suurimmat haasteet peilaamalla tämänhetkisiä toimintatapoja teoriaosuudessa esiteltyihin konsepteihin. Tältä pohjalta analysoidaan ratkaisuvaihtoehtoja, joilla tunnistetut haasteet voidaan ratkaista. Nykytilan selvittämiseksi haastattellaan organisaation avainhenkilöitä ja seurataan verkkoyksikön päivittäisiä työrutiineja. Tutkimus paljastaa suurimpien haasteiden liittyvän palvelukuvauksiin, kustannusten keräämiseen sekä allokointiin. Tulosten pohjalta esitetään, että palvelukuvausten sisältöä tarkennetaan ja palvelurakenne jaettaan selkeämmin vertikaalisiin teknologia-alueisiin. Tämä rakenne mahdollistaa aktiviteettipohjaisen kustannusmallin käyttöönoton nojaten horisontaalisiin aktiviteetteihin. Näin kustannukset saadaan kohdistettua palveluille tarkemmin. Uuden kustannusmallin pohjalta hinnoittelu- ja veloituskäytännöt yksinkertaistuvat käyttämällä kustannuspohjaista hinnoittelua.The purpose of this thesis is to investigate how an organization can improve and organize its charging activities in data center network environment. Theory part of this study introduces relevant concepts for this case and discusses their properties. Case study in this thesis is conducted to form an overall picture about current challenges in the current environment and compare it to general practices used in the industry. Based on the case study results, future state and improving actions are proposed. Theory part of this study is divided in three topics. First, service management practices based on ITIL processes are explored. Second part concentrates on network services that are relevant in data center environment. Third and last theory part explores the economical models related to network services. Theories related to cost collection and allocation, pricing and charging are discussed. The empirical part of this study rejects the explored theories to recognize the largest challenges and analyzes possible solutions to solve these challenges. The current state in the organization is mapped by interviewing key personnel and observing the daily working routines of network unit. Case study reveals that the main challenges lie in the service definitions and cost collection and allocation practices. Based on the results, service definitions are proposed to be written out in more detail and service structure is to be divided into vertical technology areas. This structure will allow more accurate cost collection using horizontal activities. Based on the new costing structure, pricing and charging practices are simplified using cost-based pricing