Vulnerability Analysis against Natural and Technological Threats: A Comparative Assessment in Tehran Metropolis Gas Supply Network

Resilience as a counterpoint to vulnerability can reduce the vulnerability of various natural, man-made, and technological threats in complex technical systems. The present study was designed and conducted with the aim of comparative assessment of the vulnerability of a gas supply network to natural and technological threats. This descriptive-analytical and cross-sectional study was carried out in Tehran metropolis gas supply network including town board stations, gas supply, and distribution networks in 2019-2020. The study was based on the vulnerability analysis method including three factors of likelihood, severity of consequences, and the degree of preparedness for threats. Comparative vulnerability assessment in these three sections of the gas supply network was performed using IBM SPSS software v. 23.0. Out of eleven identified hazardous elements, the vulnerability index for three hazardous elements was estimated as a weak level threat; four hazardous elements as a medium level threat and the vulnerability index for four hazards were evaluated as a severe threat. The results of comparative vulnerability assessment based on three parts of gas supply network showed that the highest vulnerabilities related to the gas distribution network (133.66±24.63), gas supply network (115.0±35.35), and town board stations (79.49±68.51. In addition, the results of Kruskal-Wallis test showed that the vulnerability difference in these three sections was not significant (p>0.05). The findings of the comparative assessment of vulnerability between different parts of the gas supply network including town board stations (TBS), gas supply and distribution network indicated that the resilience of these parts is relatively low and requires special attention in order to reduce vulnerability in Tehran metropolis gas supply network.

CFD Design of Waste Heat Boiler Burner in the Education System of Masters Heat Engineering Specialties

Modern CFD methods for calculating combustion processes make it possible to take into account changes in temperatures, heat loads, rates of coolants, as well as further changes in fuel quality. To develop the skills of CFD design and understanding of combustion processes among future specialists in thermophysical specialties, work was carried out to simulate the burner device of a waste heat boiler. For the study, the design of the gas burner of the waste heat boiler RB-70-4.0-440, which operates as a part of the power unit at the LLC “Rubezhansky Cardboard and Container Plant” in the city of Rubezhnoe, was selected. When constructing a geometric model, the hydraulic resistance to the flow of the supply and distribution manifolds was taken into account. To simplify the calculations, the problem was carried out in a two-dimensional, axisymmetric formulation. Analyzing the computational combustion models, the Non-Premixe Combustion model was chosen, which made it possible to take into account the entry of fuel and oxidizer into the reaction zone by two different flows, as well as turbulent diffusion flame propagation. Six variants of models were investigated: the first three variants with a flame tube with a solid disc with diameters of 32, 48, 56 mm, the next three variants, had a burner with a discontinuous disk 32 mm in diameter at a distance of 6, 16, 32 mm from the flame tube. As a result of the research, the optimal shape of the burner was chosen, which corresponds to model 4, and provides a high-quality combustion process, as evidenced by the high temperature of the torch and the lowest temperature at the disk. The conducted research gives future masters the skills of modeling combustion processes in power equipment.

Global Energy Poverty: Nigeria as a Case Study

The deplorable condition of energy supply and distribution, generally called vitality neediness has been distinguished as one noteworthy failure militating against the satisfaction of Nigeria's objective of achieving financial improvement. The objectives of this study are to identify the challenges that limit the development and accentuate the stagnancy and near decline in Nigeria's energy sector. AmartyaSen's Capability approach was the theory that provided the framework for the study. The comfort examining the system, purposive inspecting procedure and the arbitrary determination method were utilized. The purposive examining strategy was utilized to choose five (5) respondents from the best administration staff of the power segment for the inside and out meetings, while the random sampling technique was utilized in selecting discussants for the Focus Group Discussions. Findings revealed that that the pervading challenges that impede the development of the electricity sector in the country are the insufficient financial capacity to purchase huge power generating sets or maintain the existing ones, the commercial unavailability of the electricity sector that renders it unattractive to prospective investors, consumers' unwillingness to pay for electricity units at cost-reflective prices. In conclusion, the findings of research indicate that energy poverty possesses an adverse effect on both individual and economic well-being of the nation. The study recommends that more funding, both from private individuals and government is required to enhance electricity generation, transmission and distribution in the country. It also recommends a revitalization of the country's electricity sector, to make it more commercially viable and attractive to an investor.

COVID-19 affected the food behavior of different age groups in Chinese households

The COVID-19 pandemic brought profound changes to all corners of society and affected people in every aspect of their lives. This survey-based study investigated how household food related matters such as food sourcing and consumption behaviors of 2,126 Chinese consumers in different age groups changed approximately two months into the COVID-19 quarantine. A new food sourcing mechanism, community-based online group grocery-ordering (CoGGO), was widely adopted by households, particularly among the youngest group studied (18–24 years of age). The same group showed a higher confidence in the food supply system during the quarantine and a greater propensity for weight gain while staying-at-home. The more mature age group (≥35 years of age) showed heightened vigilance and awareness, with fewer grocery-shopping trips, a higher tendency for purchasing extra food, and less tendency to waste food. Survey findings of the new food-sourcing mechanism, attitudes to food, and changes in behavior among different age groups provide valuable insights to guide policies and management interventions to address matters pertaining to food supply and distribution, food access and household food security, and food waste reduction.

Smart Technologies for Sustainable Water Management: An Urban Analysis

As projections highlight that half of the global population will be living in regions facing severe water scarcity by 2050, sustainable water management policies and practices are more imperative than ever. Following the Sustainable Development Goals for equitable water access and prudent use of natural resources, emerging digital technologies may foster efficient monitoring, control, optimization, and forecasting of freshwater consumption and pollution. Indicatively, the use of sensors, Internet of Things, machine learning, and big data analytics has been catalyzing smart water management. With two-thirds of the global population to be living in urban areas by 2050, this research focuses on the impact of digitization on sustainable urban water management. More specifically, existing scientific literature studies were explored for providing meaningful insights on smart water technologies implemented in urban contexts, emphasizing supply and distribution networks. The review analysis outcomes were classified according to three main pillars identified: (i) level of analysis (i.e., municipal or residential/industrial); (ii) technology used (e.g., sensors, algorithms); and (iii) research scope/focus (e.g., monitoring, optimization), with the use of a systematic approach. Overall, this study is expected to act as a methodological tool and guiding map of the most pertinent state-of-the-art research efforts to integrate digitalization in the field of water stewardship and improve urban sustainability.

Blockchain insisted resilience enhancement of power electricity markets using distributed energy trading

The resilience of the power grid is taking a vital role in the energy supply and distribution process. But due to the rapid growth of integration of renewable distributed energy sources to the traditional power grid, the nature of the trading system is shifted from the centralized to decentralized or distributed manner. Blockchain is one of the most emerging security technologies that change the dimension of the financial and energy sector with openness and complete freedom. Blockchain implemented distributed energy trading promotes decentralized electricity markets. The physical system consists of the planning of the routing of energy from one place to another. A user can not send power to another customer in any severe outage or natural disaster in a traditional system. The user cannot participate in the trade globally. So in this proposed methodology, the connections of each customer to the central grid through several microgrids have been shown. In this work, an innovative approach in trading and finding a solution to a payment method is proposed. Ethereum blockchain-based smart contracts completed the entire trading system in automation mode in our proposed system. Any power outage at one place can be compensated by routing a new path of energy inflow from another active source, which enhances the system’s resiliency to a certain degree. While trading, no third parties will be engaged so that the transaction is efficient and fast.

Improving Household Agriculture with Roof-Harvested Rainwater: A Case Study in Sydney and Nairobi

The production and distribution of a sufficient quantity of food and water of satisfactory quality is at the heart of sustainable development. At the small domestic scale, roof-harvested rainwater can make a significant contribution to food supply and distribution systems (production, handling, storage, and transportation). In this paper, we compare the potential crop production of a small garden plot using three methods of watering: (1) rainfed only with no irrigation; (2) irrigated with the ideal amount of water; and (3) rainwater tanks of various sizes installed and used to irrigate the plot. Yield was determined on the basis of the yield calculation method presented in FAO 33. It was found that yields can be increased considerably by installing a correctly managed rainwater storage system (RSS). A 3 kL RSS connected to a 120 m2 roof can increase yields in Nairobi from 40 kg to 96 kg. In Sydney, a larger roof of 200 m2 can increase yields from 66 kg to 143 kg. This study makes an important contribution to water and food security-related sustainable development goals.

Development of the method of determining the location of a short circuit in transmission lines

One of the serious problems of the reliable functioning of energy systems is the disruption of the performance of overhead and cable transmission power lines caused by various reasons. Most of the power outages occur in distribution networks. Particularly dangerous short-circuits in the supply and distribution network, due to unpredictable natural disasters. To ensure uninterrupted and reliable power supply to consumers, it is necessary to identify and eliminate the malfunction in a short time to reduce damage. Finding and troubleshooting a line is an important task. The authors proposed a method for quickly determining the location of a short circuit in power lines. The proposed method allows to reduce search time and increase the accuracy of determining the fault location.

Development and Integration of the Dual Fuel Combustion System for the MGT Gas Turbine Family

Industrial gas turbines like the MGT6000 are often operated as power supply or as mechanical drives. In these applications, liquid fuels like 'Diesel Fuel No.2' can be used either as main fuel or as backup fuel if natural gas is not reliably available. The MAN Gas Turbines (MGT) operate with the Advanced Can Combustion (ACC) system, which is capable of ultra-low NOx emissions for gaseous fuels. This system has been further developed to provide dry dual fuel capability. In the present paper, we describe the design and detailed experimental validation process of the liquid fuel injection, and its integration into the gas turbine package. A central lance with an integrated two-stage nozzle is employed as a liquid pilot stage, enabling ignition and start-up of the engine on liquid fuel only. The pilot stage is continuously operated, whereas the bulk of the liquid fuel is injected through the premixed combustor stage. The premixed stage comprises a set of four decentralized nozzles based on fluidic oscillator atomizers, wherein atomization of the liquid fuel is achieved through self-induced oscillations. We present results illustrating the spray, hydrodynamic, and emission performance of the injectors. Extensive testing of the burner at atmospheric and full load high-pressure conditions has been performed, before verification within full engine tests. We show the design of the fuel supply and distribution system. Finally, we discuss the integration of the dual fuel system into the standard gas turbine package of the MGT6000.

Implementation of electronic models of water supply and wastewater disposal systems

За период с 2013 г. ООО «Самарские коммунальные системы» в рамках внедрения и развития электронных моделей систем водоснабжения и водоотведения приобрело программное обеспечение, организовало процесс паспортизации и актуализации сетей водоснабжения и водоотведения, опробовало различные методы поиска скрытых потерь воды на сетях водоснабжения с использованием результатов их гидравлического моделирования, произвело оценку различных перспективных мероприятий развития системы подачи и распределения воды и отведения стоков, сформировало алгоритм взаимодействия различных программных продуктов и сотрудников, работающих с ними, провело работы по обеспечению требований по охране сведений, относящихся к государственной тайне, разработало мероприятия по поддержанию ранее достигнутых результатов по устранению потерь воды. В настоящее время разрабатываются полномасштабные детализированные гидравлические модели систем водоснабжения и водоотведения, отрабатывается механизм передачи данных сбытового подразделения об объемах реализованных услуг непосредственно в гидравлическую модель. Since 2013, «Samarskie Kommunal’nye Sistemy», LLC, within the framework of the implementation and development of electronic models of water supply and wastewater disposal systems, acquired the software, arranged the process of certification and updating of water distribution and sewer networks, tested various methods of detecting latent water losses in the water distribution networks using the results of hydraulic modeling, assessed various promising measures for the development of the water supply and distribution system and wastewater disposal, developed an algorithm for the interaction of various software products and employees working with them, carried out measures on meeting the requirements for the protection of information related to the National Security Information, developed measures to maintain previously achieved results in eliminating water losses. Currently, full-scale detailed hydraulic models of the water supply and wastewater disposal systems are being developed, a mechanism is being tested for transferring data from the sales department on the volumes of provided services directly to the hydraulic model.