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At head of title: Engineering and design. ; Cover title. ; Mode of access: Internet. ; 2

The modern community is an organically assembled system of people, organizations, and infrastructures, as well as patterned interdependences and interactions. Functioning of modern communities relies on the continuous production and distribution of the essential goods and services, accomplished by large-scale, man-made, networked systems, called infrastructures. Such infrastructures are termed critical if their incapacity or malfunction could have a devastating impact on the health, security, and social well-being of community inhabitants. As exemplified by many recent occurrences, critical infrastructure systems in diverse communities across the spectrum of wealth have not been sufficiently robust and have not recovered quickly enough after severe natural disasters, with long-lasting physical damage and technical failures causing significant hardships and economic losses. Against this backdrop, it is imperative to comprehensively investigate, understand and model the disaster resilience of critical community infrastructure systems. Among such critical infrastructure systems, the Electric Power Supply System (EPSS) stands at the core of a modern community. Among many natural hazards, the earthquake hazard stands out as potentially the most devastating and the most difficult to predict. Therefore, this thesis is focused on modeling and assessment of seismic resilience of EPSS and the community it serves. The study begins with a review and an examination of the merits and drawbacks of the resilience modeling and assessment of current civil infrastructure system seismic resilience modeling frameworks. An important common shortcoming is the focus solely on the supply capacity of the infrastructure systems. To overcome this shortcoming, a measure of EPSS-Community system functionality and seismic resilience is formulated by comparing the service supply provided by the EPSS to the Community and the service demand generate by the Community. The supply/demand approach to quantify the seismic resilience of an EPSS-Community system is demonstrated using a virtual EPSS-Community system. A direct measure of the seismic resilience of the EPSS-Community system, the gap between the electric power supply and demand, is proposed in this thesis. This measure is tracked from the time an earthquake occurs until the EPSS-Community system has recovered to yield instantaneous and cumulative measures of resilience. One such instantaneous seismic resilience measure, the percentage of people without power (PPwoP) at any time after an earthquake, can serve as a societal measure of EPSS-Community system systemic resilience. While the robustness of the EPSS-Community system is crucial for reducing the impact of an earthquake, the post-earthquake recovery process is critical to the seismic resilience of EPSS-Community system. This post-earthquake recovery process is case-specific, given their unique characteristics of EPSS and Community physical vulnerability, and dynamic, given the interactions among different infrastructure systems, community sectors, and the political and economic governance structures put in place after the disaster. An Agent-Based model is developed in this thesis to capture the unique dynamic characteristics of the EPSS-Community system seismic recovery process. Two individual agents, the EPSS Operator and the Administrator, are specified using a set of parameters to define their individual behavior and interactions. The effect of agent parameters and their interactions is identified in simulations of the seismic recovery process of a virtual EPSS-Community using the supply/demand approach. The post-earthquake restoration of a modern EPSS is contingent upon the post-earthquake serviceability of other critical infrastructure systems, in particular upon the serviceability of the transportation systems (TS) of the community. To investigate this interdependency among the community infrastructure systems, the virtual EPSS-Community system is expanded to include a transportation system, and a third agent, the TS Operator, is added to the model. The conducted case studies demonstrate that the interplay among different agents, as well as the interdependency between the civil infrastructure systems, determine the recovery path for the integrated EPSS-TS-Community system. The community resources available for post-earthquake recovery are finite. A network-theoretical model is used to gauge the impact of the quantity of the disposable repair resources and work crews on the seismic recovery for EPSS-TS system. The case study simulation results clearly indicate the rate of EPSS-TS system recovery is affected by the amount of available resources, but, importantly, that an optimal distribution of the available resources between the EPSS and the TS can significantly reduce the system recovery time and, thus, increase its seismic resilience. The presented scientific findings lay the foundation for a comprehensive and integrated resilience assessment on the EPSS-Community system based on the proposed agent-based network-theoretical supply/demand framework. Further work on generalizing the model by including all community infrastructure systems and refining their interactions in the model can be done using the proposed framework to investigate the interdependencies among the infrastructure systems and optimize community governance actions. Inclusion of dynamic models of community and infrastructure system post-disaster behavior, such as movement of the population, restructuring of the infrastructure and the effects on the production and consumption of goods and services, would make it possible to examine how disaster resilience of the integrated critical infrastructure systems shapes the long-term socio-economic development of the communities.

Abstract
The paper presents dynamical models of controlling voltage and frequency of ship's electric supply set. The simulation model of synchronous generator, implemented in Matlab/Simulink, was described. For the developed simulation model, developed control systems using fuzzy controllers type P and PD were presented. Simulation research for resistance, inductive and capacitive loads were carried out for these regulators. Sample results of simulation tests are presented in the form of voltage waveforms at the output of the generator and rotational speed of the internal combustion engine for various load conditions. The conducted tests allow to assess the quality of the control process using fuzzy controllers and thus ensure the selection of the optimal solution.

The issue of erratic and epileptic power supply in Nigeria Electricity Company is as old as the country itself. This is not unconnected to some factors such as: inadequate power generated in the national grid, electric power losses in the distribution network, government instability and unstable power reform policies, to mention but a few. The effects of erratic and epileptic power supply have been a major challenge to every sector in Nigeria especially the telecommunication industry. The telecommunication industry plays a significant role in the growth and development of every nation. Hence, this paper aims at critically investigating the causes and effects of erratic and epileptic electric power supply in Nigerian telecommunication industry. More so, the paper suggested and recommended ways to curb and enhance the current erratic and epileptic power situation in the country in order to boost the productivity of telecommunication industry and other sectors as well.

Energy infrastructures in North-Central Nigeria are inadequate and grid electricity is unable to meet suburban housing electricity demand. The alternative power-supply options proposed by government for the region require appropriation analysis for selection. Four public housing estates in suburban Abuja are selected for electricity demand analysis under conventional and energy-efficient lighting scenarios; then techno-economic parameters of two off-grid electric power supply systems (PV and Diesel-powered generation) to meet these electricity demands are evaluated. An energy techno-economic assessment methodology is used. The study determines the energy-efficient lighting system is appropriate with 40% energy savings relative to the Conventional Lighting Systems. The diesel generator alternative power-supply option has Life Cycle Costs almost 4 times those of the PV option. The study established the PV-energy-efficient lighting system as the most feasible off-grid electric power supply alternative for implementation.

Abstract
Currently a much higher number of portable devices with improved functionality supporting our job-related and social activities require higher and higher capacity and power offered by sources of power supply. Theoretical analysis of the possibility to achieve exploitation features of currently known portable sources of electric current has led the author to a conclusion that even the best solutions will not meet the desired mass and volume magnitudes in relation to the energy supplied. Therefore, if the sources of energy have reached the physically and economically justified capability limits and they are characterized by significantly varied exploitation properties, a solution combining the advantages of various sources of energy through energy management seems to be sensible. In this connection this article presents the idea of a system of energy control, which using available cells will allow for reducing the weight of power supply systems. The considerations are based on defense-related applications, this, however, does not exclude applications for civilian purposes.

The electric power industry is uniquely vulnerable to natural and human-made risks such as natural disasters, climate change, and cybersecurity. This study proposes a vulnerability assessment framework to identify and assess the risks associated with the electric power supply chain in the United Kingdom and study the causal relationship among them with the neutrosophic revised decision-making trial and evaluation laboratory (NR-DEMATEL) method. We further introduce a novel hesitant expert selection model (HESM) to assist decision-makers with expert selection and weight determination. We present a case study in the United Kingdom power supply chain to demonstrate the applicability and efficacy of the proposed method in this study. This is the first comprehensive risk interdependence analysis of the United Kingdom's power supply chain. The findings reveal natural disasters and climate change are the most crucial risks followed by industrial action, affordability, political instability, and sabotage/terrorism.

Key problems of the regional electric power supply systems are examined. These problems result from a lack of regulated interaction mechanisms for uniting the different entities' resources aimed at the realization of investment activities. One of the main problems of the power supply industry is physical and moral aging of both generating and networking equipment. In the article, the necessity of management system formation to control the development of power sector has been proved. The deficiencies of the modern investment procedure in power companies are described. The absence of continuity between the regional and local strategic planning documents and investment planning of a power company has been found out. The possibility to develop a new mechanism for attracting investment has been proposed. The regulation of joint activities to implement the development program for the regional power supply industry has been proposed. The management system to develop the Russian power industry has been proposed. The comparative analysis of generating capacity development mechanisms has been carried out, such as capacity supply agreement (CSA), investment support mechanism (ISM), and long-term power market (LPM). The interaction procedure of the planning of the power supply infrastructure development has been described. The mechanism connecting the state sectoral and regional planning and corporate planning of power supply infrastructure development has been proposed. The regional aspects of industrial policy and its legislative support have been considered. To successfully implement the public-private-partnership (PPP) projects, it is necessary to create the effective PPP model within the federal and regional legislation framework; to develop the financial model providing the recoverability of investments; to provide a mutually beneficial cooperation between executive bodies and private investors. The possibility to apply the PPP mechanism for regional power supply infrastructure development have been validated. The PPP mechanism application can help to solve the problem of regional and interregional power supply infrastructure development, as it is of vital importance for the regions of Siberia and the Far East. ; Рассмотрены проблемы региональных энергетических систем, связанные с отсутствием регламентированных механизмов взаимодействия для объединения ресурсов различных субъектов в целях осуществления инвестиционной деятельности. Обоснована необходимость формирования системы управления развитием электроэнергетики. Описаны недостатки схемы организации современного инвестиционного процесса в энергетических компаниях. Показано отсутствие преемственности между региональными и местными документами стратегического планирования и инвестиционным планированием энергетической компании. Предложена возможность разработки нового механизма привлечения инвестиций. Представлена система управления развития электроэнергетики России.