Infrastructure Integration Research Articles

Assessing the Performance of Primary School Information Management Systems (PReM) in Data Provision: A Focus on Two Selected Public Primary Schools at Temeke Municipal Council, Dar es Salaam, Tanzania

The study aimed to assess the performance of Primary School Information Management Systems (PReM) in data provision at Dar es Salaam city. Specifically, the study aimed to determine the school-based requirements to deploy PReM for students - data collection, examine the impacts of PReM utilization, and explore stakeholders feeling on the use of PReM in education aspects from Mtoni Kijichi and Bwawani Primary School at Temeke Municipality, This study was guided by Information Systems Theory and Data Quality Theory. The study adopted a cross-sectional design collecting quantitative data through surveys and questionnaires. Interview and documentary review were utilized to collect the qualitative data. The study adopted non-probability and purposive sampling techniques for selecting 399 respondents (School pupils, parents, academic teachers, Ward Executive Officers, and Examination Administration and Certification Directorate staff) from the total population within the study area. Descriptive statistics (frequency), thematic and multiple linear regression models were used for analysis. Research findings from specific objective one portray that hardware with high capability has been purchased, stakeholder involvement before launching any information management system is important, and the implementation of the system must comply with regulations and pilot conducting before full implementation. Moreover, on the impacts of PReM utilization towards accuracy data provision, multiple linear regression results divulge that the independent variables (reduced workload, time savings, improved monitoring, data-driven interventions, enhanced learning outcomes, data accuracy as well as security and privacy) lead the positive relationship with PReM performance. Furthermore, respondents had positive feelings concerning the use of PReM in education aspects. The study conclude that availability of adequate hardware (Computers, tablets, and servers), reliable internet connectivity, robust network infrastructure, and compatibility with existing school management systems are the main school-based requirements for PReM deployment in student data collection. The study recommended that National Examinations Council of Tanzania (NECTA) in collaboration with MoEST had to ensure improved PReM infrastructure and training programs for smooth integration and better school management and performance.

Green Streets, Healthy Hearts: Exploring the Roles of Urban Nature and Walkability in Cardiovascular Health.

With the growing evidence that connects urban environments with public health outcomes, the role of urban planning has become increasingly critical in addressing public health challenges. Cardiovascular diseases (CVDs) are the leading cause of mortality in urban areas and worldwide and are impacted by characteristics of the built environment, such as walkability and nature exposure. In this literature view, we explore the influence of the physical built environment, specifically green spaces and walkability, on cardiovascular health. Results from prior studies show a clear reduction in cardiovascular disease-related risk factors, morbidity, and mortality in neighborhoods that integrate green spaces and/or walkability. Cumulative evidence suggests that urban environments that integrate green spaces (such as parks) and walkability (eg, safe sidewalks) can significantly improve cardiovascular health. Urban planning policies and strategies that prioritize the integration of green infrastructure and walkable designs can contribute to improving cardiovascular health in urban residents while also enhancing the overall well-being and quality of life.

Implementation of Sports Science and Technology Integration Infrastructure: A Case Study of Speed Skating Utilizing Web and Mobile Applications, and Information Visualization Technologies

In the field of sports, there is an active discussion on and an attempt to apply technologies that integrate sports with cutting-edge science and technology for the purpose of enhancing athletic performance. In line with this trend, South Korea is supporting research on the fusion of sports and science technology at an interdepartmental level. For the improvement of performance in elite sports, it is important to consider the athlete’s skills, the coach’s information analysis, the scientification of equipment, and the environmental optimization. Accordingly, this study aims to propose web and mobile app technologies to establish an integrated infrastructure of sports science and technology for the three factors of athletes, equipment, and environment to improve the performance of speed skating. Furthermore, it aims to make policy recommendations to activate this integration. The application of such technologies and policy recommendations can be transferred and organically integrated into other sports, including track and field, which are time-based competitions. Additionally, it is expected that this approach will lead to the formation of new theories that consider the emotional aspects occurring in sports situations.

Application of Internet of Things (IoT) in Energy Infrastructure: Lessons for the Future of Operations and Maintenance

The application of the Internet of Things (IoT) in energy infrastructure is revolutionizing operations and maintenance practices, driving efficiencies, and enhancing sustainability across the sector. This paper explores the transformative impact of IoT technologies on energy infrastructure, focusing on how they facilitate real-time monitoring, predictive maintenance, and data-driven decision-making. By leveraging IoT devices and systems, energy operators can optimize performance, reduce operational costs, and minimize downtime, ultimately contributing to more resilient and sustainable energy systems. The discussion highlights key IoT applications within energy infrastructure, including smart grids, renewable energy systems, and conventional power plants. Smart sensors and devices enable continuous data collection, providing insights into equipment performance, energy consumption, and environmental conditions. Predictive analytics, powered by IoT data, allows operators to anticipate equipment failures and conduct maintenance proactively, thereby extending asset life and improving reliability. Additionally, the abstract addresses the challenges associated with IoT integration in energy infrastructure, such as cybersecurity risks, data management issues, and the need for interoperability among diverse systems. It emphasizes the importance of establishing robust security protocols to protect sensitive data and ensure the integrity of IoT networks. Furthermore, the role of regulatory frameworks and industry standards in promoting the safe and effective deployment of IoT technologies is discussed. The paper also examines case studies of successful IoT implementations in energy infrastructure, showcasing the lessons learned from these initiatives. These examples illustrate the potential for IoT to enhance operational efficiency, reduce greenhouse gas emissions, and support the transition to cleaner energy sources. In conclusion, the abstract underscores that the adoption of IoT technologies in energy infrastructure is not just a trend but a necessity for the future of operations and maintenance. As the energy sector continues to evolve, embracing IoT will be crucial for achieving sustainability goals and meeting the growing demands for reliable energy supply.

Biofuser: a multi-source data fusion platform for fusing the data of fermentation process devices.

In the past decade, the progress of traditional bioprocess optimization technique has lagged far behind the rapid development of synthetic biology, which has hindered the industrialization process of synthetic biology achievements. Recently, more and more advanced equipment and sensors have been applied for bioprocess online inspection to improve the understanding and optimization efficiency of the process. This has resulted in large amounts of process data from various sources with different communication protocols and data formats, requiring the development of techniques for integration and fusion of these heterogeneous data. Here we describe a multi-source fusion platform (Biofuser) that is designed to collect and process multi-source heterogeneous data. Biofuser integrates various data to a unique format that facilitates data visualization, further analysis, model construction, and automatic process control. Moreover, Biofuser also provides additional APIs that support machine learning or deep learning using the integrated data. We illustrate the application of Biofuser with a case study on riboflavin fermentation process development, demonstrating its ability in device faulty identification, critical process factor identification, and bioprocess prediction. Biofuser has the potential to significantly enhance the development of fermentation optimization techniques and is expected to become an important infrastructure for artificial intelligent integration into bioprocess optimization, thereby promoting the development of intelligent biomanufacturing.

Optimizing Sustainable Urban Mobility: Integration Of Electric Vehicle Charging Infrastructure Into Smart Buildings

The integration of electric vehicle (EV) charging infrastructure into smart buildings is a crucial step toward enhancing sustainable urban mobility. This paper explores the benefits, challenges, strategies, and best practices associated with this integration, with a focus on optimizing EV charging accessibility and promoting a cleaner transportation ecosystem. Traditional vehicles powered by fossil fuels contribute significantly to pollution and greenhouse gas emissions, highlighting the urgent need for sustainable alternatives. EVs offer reduced emissions, lower operating costs, and potential energy independence through renewable sources, making them a promising solution for urban mobility challenges. Despite these advantages, the widespread adoption of EVs faces hurdles, particularly regarding charging infrastructure availability and accessibility in urban areas. Range anxiety among EV users due to insufficient charging stations is a significant concern hindering the transition to electric transportation. The paper emphasizes strategic placement of charging stations, integration with renewable energy sources like solar panels, and utilization of smart grid technologies to optimize EV charging operations. Case studies such as Tesla Gigafactory Shanghai and Googleplex showcase successful implementations, demonstrating scalability, user-centric design, and seamless integration with building management systems. Key challenges such as funding constraints, technical interoperability, and grid integration are addressed, proposing solutions like innovative financing models, standardization efforts, and advanced grid management technologies. By addressing these challenges and implementing sustainable solutions, the integration of EV charging infrastructure into smart buildings can significantly contribute to reducing environmental impact, promoting cleaner transportation options, and fostering a more sustainable and resilient urban environment

Use of Vertical Greenery Systems for the domestic scale treatment of greywaters for fit-for-purpose reuse. Applicability and future prospects.

Abstract Only less than 1% of the Earth’s water is fit for human activities. Domestic consumption accounts for roughly 20% of all uses of water, adding pressure to the increasing water scarcity stress. Water intakes of residential buildings for all everyday uses are constituted by a high-quality resource, which is either costly to produce or conspicuous in amounts to withdraw from natural sources. The present proposal aims to test the feasibility of the application of decentralized greywater treatment strategies, based on the use of vertical greenery systems integrated into residential buildings to assess both the optimal scale of application in residential settlements and a comparative analysis on reclaimed water resource savings. The aim is to promote the circular use of water resources by allowing for fit-for-purpose employment, thus reducing the overall intake due to the residential sector. The methodology hereby proposed has been developed using as a case study the most widespread residential typologies in the Southern Italian context, such as single detachment, row houses, low and medium-rise apartment buildings. The result is the proposition for each residential typology of a retrofitting strategy that employs the integration of a green infrastructure inside the residential spaces. Until now, the Mediterranean context has been characterized by limited use of strategies directed towards the efficient employment of water resources, since the mild climatic conditions have always provided for an adequate amount of freshwater. Therefore, limited studies have been carried out on the application of those strategies in Mediterranean landscapes. However, the rapid shift in precipitation patterns due to climate change has defined the need to quickly embrace new strategies, systems, and technical solutions for improving water use efficiency and promoting reuse.

ТЕОРЕТИЧНИЙ АНАЛІЗ ПОНЯТТЯ РЕГУЛЯТОРНА ПОЛІТИКА У ПЛАНУВАННІ ТА ЗАБУДОВІ МІСТА: ОСНОВНІ ПІДХОДИ ТА СУЧАСНІ ТЕНДЕНЦІЇ

Regulatory policy in the field of urban planning and development is a key element of public administration aimed at ensuring economic stability, social welfare and sustainable development. In the conditions of globalization and intensive technological progress, effective regulation of urban planning processes is becoming more and more important for solving modern challenges. The purpose of this study is to carry out a theoretical analysis of the concept of regulatory policy in urban planning and development, to study the main approaches to its implementation, as well as to determine modern trends and opportunities for adapting international experience for Ukraine. In particular, the research aims to identify effective models of regulatory policy that can be integrated into national legislation and practice to improve the management of urban development. The research uses a comprehensive approach, which includes the analysis of scientific publications, comparative analysis of regulatory policies of different countries, methods of critical literature review and data synthesis. Special attention is paid to the experience of countries such as the USA, Germany and Singapore, where various approaches to the regulation of urban planning processes are used. The analysis showed that regulatory policy in urban planning and development is a multifaceted phenomenon, which includes such basic approaches as zoning, strategic spatial planning, energy efficiency, integration of transport infrastructure and active involvement of the public in the decision‒ making process. Modern trends in regulatory policy have been identified, including innovative approaches to planning, the use of digital technologies, an emphasis on sustainable development and environmental safety. A comparative analysis of the regulatory policies of the USA, Germany, and Singapore made it possible to identify effective models that can be adapted to the conditions of Ukraine. The study confirmed that an effective regulatory policy is an important prerequisite for sustainable economic development, social stability and protection of citizens' rights. Further research should focus on the integration of digital technologies into regulatory processes, improvement of control and monitoring mechanisms, which will contribute to the sustainable development of cities in Ukraine.

Enhancing water management and urban flood resilience using Hazard Capacity Factor Design (HCFD) model: Case study of Eco-Delta city, Busan

This study evaluated future climate scenarios and the changes in urban flood resistance capacity in Busan Eco-Delta City using the hazard capacity factor design (HCFD) model. It analyzed the flood reduction effects of both gray and green infrastructure. Despite existing flood safety systems, there is a growing need to enhance urban flood resilience due to increasing heavy rainfall, unpredictable precipitation, and frequent typhoons driven by climate change. The HCFD model predicted urban flood volumes of Busan Eco-Delta City and analyzed the effectiveness of gray and green infrastructure in flood control. A stormwater management model (SWMM) simulated urban flood resistance capacity under the SSP1–2.6 climate change scenario. Results indicate that for an anticipated 500 mm rainfall over 3 h, green infrastructure can mitigate floods by 9 % to 17.6 %, while gray infrastructure can reduce flooding by 24 % to 32.1 %. The integration of gray and green infrastructure leads to an overall flood mitigation ranging from 47.1 % to 63.3 %. A notable contribution of this research is its predictive analysis of future flood scenarios using model-based scenario analysis and decision support algorithms, offering valuable insights into changes in urban flood resistance capacity and strategies for effective flood control decision-making.

Integration of Green and Gray Infrastructures – Conceptualization from the Perspective of Gray Engineers

Green infrastructure preserves, enhances, or restores elements of a natural system to provide higher-quality, more resilient, and lower-cost infrastructure services. Ecosystem disaster prevention and mitigation is also one of the features of green infrastructure. It is thus expected to integrate gray and green infrastructure to achieve greater resilience and sustainability. While several concepts of integrated green and gray infrastructure (IGGI), or hybrid infrastructure, have been proposed at the landscape scale, hybrid possibilities could exist at the single structural element and material scales. This paper proposes three types of IGGI concepts that could be beneficial for gray engineers to implement green infrastructure in terms of the gray engineering perspectives (safety, serviceability, and durability), primarily focusing mainly on the scale of single- or multiple-structure scales smaller than landscape scale. By categorizing the past and feasible IGGI cases into three concepts, the performance requirements for each infrastructure (green or gray) will become apparent, accelerating the discussion to develop a performance curve model as an IGGI. Also, the work needed to realize IGGI is discussed, emphasizing the urgent need for gray engineers to understand the benefits of integrating green infrastructure into gray infrastructure and thus promote the implementation of IGGI.

Exploration of the Application of Aesthetics in Transportation Teaching

Transportation is the foundation and prerequisite for the development of human society and economy, and also has aesthetic significance in beautifying human life. The development of transportation is a shift from extensive resource consumption to coordinated resource intensive use, and it is also a development in aesthetics. Guiding students to discover the beauty of transportation vehicles, the harmonious integration of transportation infrastructure and nature, the beauty of transportation data, and the beauty of the behavior and soul of transportation participants, igniting more students' curiosity for transportation majors, and inspiring their enthusiasm for the transportation industry, is the central goal of the construction of the Beauty of Transportation course.

Nature-based solutions across spatial urban scales: three cases studies from Nice, Utrecht and Milan

A holistic vision for urban sustainability looks at the city as an integration of energy, environment, mobility, urban design, new technologies and, most importantly, ‘people and nature’. In this article, the aim is to shed light on the role of nature-based solutions (NBS) towards addressing climate change crisis and tackling a variety of socio-ecological and urban biodiversity challenges. The paper claims for more evidence-based frameworks to understand the economic, social and environmental benefits of NBS and to promote their inclusion in urban policies. First, and most importantly, the role of NBS in shaping urban planning as a result of expansion and densification of cities is reviewed. Second, the co-benefits generated by NBS within the social and cultural regeneration of cities are reflected upon. Lastly, case studies are given from Nice, Utrecht and Milan in order to showcase those cities’ spatial strategies to implement NBS through different scales. The article discusses the role of NBS in addressing climate challenges and emphasises the need for collaborative stakeholder engagement in their implementation. Spatial, governance and temporal challenges related to NBS implementation are identified, underscoring the complexity of integrating NBS into urban environments. The article concludes by advocating for systematic integration of green and blue infrastructure and NBS into urban planning, emphasising the importance of considering socio-cultural elements alongside environmental benefits.

The Magnet Engine

This research paper explores Michel K. Walden's Magnetite Engine and its transformative potential in engineering. The Magnetite Engine represents a significant advancement in propulsion technology, promising greater efficiency and performance than conventional combustion engines. Through a literature review and case studies, the paper assesses the engine's theoretical and practical aspects, focusing on its impact on automotive and aerospace industries. While it offers benefits like reduced emissions and improved energy efficiency, challenges such as scaling production and infrastructure integration remain. Future research directions are proposed to fully realize the Magnetite Engine's potential for sustainable engineering solutions.

Market infrastructure integration and upgrading of resident consumption—Evidence from a panel of Chinese micro households

Using long-term household data from the China Family Panel Studies (CFPS), we examine the impact of market infrastructure integration on Chinese residents’ consumption structure improvement. The findings demonstrate that market infrastructure integration not only enhances household consumption but also particularly facilitates this improvement among rural areas and low-income groups. On one hand, market infrastructure integration boosts households’ ability to consume by increasing their income and wage income shares. On the other hand, it stimulates enterprises to invest more in product innovation, thereby enhancing the quality of consumer goods. Additionally, the influence of market infrastructure integration in promoting consumption is bolstered by internet technology and financial inclusion. However, these factors primarily stimulate demand for basic necessities rather than contributing to a shift toward higher-quality products and thus hinder efforts to upgrade the consumption structure.

Reimagining Relationships with Resources as a Public Garden: Case Studies of Longwood Gardens’ Sustainability and Stewardship Practices

Longwood Gardens (Kennett Square, PA, USA) is working toward a future where the beauty of nature can be enjoyed by all through its sustainability and stewardship efforts. Using case studies highlighting water quality and conservation, carbon footprint reduction, material circularity, and land stewardship, this paper examines the multifaceted approach that Longwood takes to address its environmental impact. First, a description of Longwood’s innovative water quality and conservation strategies and their integration of green and gray infrastructure is described. Next, the paper explores the comprehensive measures adopted to curtail its carbon footprint, from energy-efficient infrastructure to renewable energy sources. Then, Longwood’s commitment to material circularity is investigated, showcasing initiatives that reuse organic materials and create necessary products for the Gardens onsite. Finally, the Gardens’ holistic land stewardship practices are detailed, including habitat preservation and biodiversity enhancement. The paper concludes with valuable findings learned from the organization’s sustainability and stewardship journey, offering insights applicable to other gardens or campuses seeking to improve their ecological impact while maintaining a commitment to esthetic and horticultural excellence.

An urban rivers renaissance? Stream restoration and green–blue infrastructure in Latin America – Insights from urban planning in Colombia

AbstractWhile urban river restoration has become mainstream in the Global North, it remains scarce in Latin America, where most literature focuses on water quality, stream habitats, and watershed assessment, but planning and implementation lag behind. Colombia is undergoing a paradigm shift after pioneering the integration of green and blue infrastructure (GBI) into urban planning in the early 2000s (namely Estructura Ecológica Principal). A surge in river renaturalization initiatives is underway, with large and intermediate cities planning and executing projects. We systematically assessed the integration of rivers and GBI into local policies (Planes de Ordenamiento Territorial) and found widespread and strong recognition of streams, wetlands, and ecosystem services in urban planning, higher than previously reported. Most cities emphasize river multifunctionality, ecological connectivity, public space, and recreation, as well as disaster risk reduction, advancing toward sustainable urban water and drainage systems. However, significant gaps persist regarding climate change resilience, participation, and social justice. In a region marked by high inequality, pre-existing spatial exclusion could be amplified by urban renewal, greening, and tourism due to unfair resettlement conditions and gentrification. Such trade-offs can undermine the ecological and social benefits of restoration. We highlight the crucial role of civil society and grassroots activism in protecting and defending urban commons and conclude by recommending a critical examination of GBI and river restoration efforts in Latin America. Colombia’s case can serve as both a reference and a cautionary tale for other cities in the region to achieve outcomes that promote equity and justice amid pressing social and environmental challenges.

Network Security Challenges and Countermeasures for Software-Defined Smart Grids: A Survey

The rise of grid modernization has been prompted by the escalating demand for power, the deteriorating state of infrastructure, and the growing concern regarding the reliability of electric utilities. The smart grid encompasses recent advancements in electronics, technology, telecommunications, and computer capabilities. Smart grid telecommunication frameworks provide bidirectional communication to facilitate grid operations. Software-defined networking (SDN) is a proposed approach for monitoring and regulating telecommunication networks, which allows for enhanced visibility, control, and security in smart grid systems. Nevertheless, the integration of telecommunications infrastructure exposes smart grid networks to potential cyberattacks. Unauthorized individuals may exploit unauthorized access to intercept communications, introduce fabricated data into system measurements, overwhelm communication channels with false data packets, or attack centralized controllers to disable network control. An ongoing, thorough examination of cyber attacks and protection strategies for smart grid networks is essential due to the ever-changing nature of these threats. Previous surveys on smart grid security lack modern methodologies and, to the best of our knowledge, most, if not all, focus on only one sort of attack or protection. This survey examines the most recent security techniques, simultaneous multi-pronged cyber attacks, and defense utilities in order to address the challenges of future SDN smart grid research. The objective is to identify future research requirements, describe the existing security challenges, and highlight emerging threats and their potential impact on the deployment of software-defined smart grid (SD-SG).

Integration of LoRa-enabled IoT infrastructure for advanced campus safety systems in Taiwan

Amid rising concerns about campus safety in Taiwan, particularly with the global trend towards smart cities, integrating the Internet of Things (IoT) into institutional security frameworks has become pivotal. The paper discusses the implementation of using iBeacons and Long Range (LoRa) technology to locating the student position and ensure his safety in the school campus. It uses Internet of Things (IoT) approach in real time to monitor and locate the student presence in the school compound. This paper unveils an innovative design for a campus security system that harnesses the LoRa technology. In the system, the students are equipped with devices containing Bluetooth Low Energy (BLE) beacons to capture and transmit real-time location data. The system response time to locating student in abnormal locations such as cornered and concealed areas is about one second. By extending this system to cover all individuals on campus, a closely monitored environment and areas is enabled that significantly bolstering the security measures. This not only furnishes a dynamic protective layer for educational institutions but also serves as a proactive deterrent against potential security breaches. Ultimately, this research underscores the transformative potential of merging IoT with campus security to ushering in a new era of student safety. LoRa technology offers advantages in battery life, cost-effectiveness, deployment flexibility, and network coverage etc. Therefore, this paper ultimately provides a method of how to utilize the LoRa technology to develop a campus security system. Unlike artificial intelligence (AI)-based image recognition, which raises concerns about privacy and human rights; the features of LoRa’s long-range communication and low power consumption make it a more suitable choice.

IHST (Integrated, Holistic, Spatial, and Thematic) Flood Management Model: The Integration of Flood Model, Green Infrastructure and Non-Structural Mitigation in the Urban Area of Barabai City

Abstract The January 2021 Floods paralyzed the entire Hulu Sungai Tengah Region, South Kalimantan Province, Indonesia, submerging 20,553 houses, causing minor damage to 2,973 houses, severe damage to 268 houses, and resulting in losses exceeding 53 million dollars. The Barabai Urban Area was one of the locations severely affected by flood. The flood management was conducted in the Barabai urban area to predict and visualize water movement during flooding, aiding in understanding and mitigating flood risks, as well as developing effective flood management strategies. The flood management was carried out adopted the IHST Model, which is the abbreviation from Integrated, Holistic, Spatial, and Thematic. The activities involve HECRAS 6.2 application, utilizing Google Earth terrain data, river geometry data, and flood discharge analysis based on the Nakayasu method. The analysis results highlighted the need for both structural and non-structural flood interventions. Non-structural interventions aiming to reduce vulnerability and enhance community capacity in facing flood. Structural developments involved the construction of storm water retention ponds and river embankments at specific locations based on the flood modelling results. The concept of polder and river embankment development was approached through green infrastructure principles, as flood management solutions should not only facilitate rapid water drainage but also improve soil absorption to prevent prolonged inundation.

Transitioning to a renewable hydrogen system: Optimal infrastructure for self-sufficient hydrogen supply in Austria by 2030

In this study, we employ an optimization model to optimally design a self-sufficient, independent of any imports and exports, hydrogen infrastructure for Austria by 2030. Our approach integrates key hydrogen technologies within a detailed spatial investment and operation model – coupled with a European scale electricity market model. We focus on optimizing diverse infrastructure components including trailers, pipelines, electrolyzers, and storages to meet Austria's projected hydrogen demand. To accurately estimate this demand in hourly resolution, we combine existing hydrogen strategies and projections to account for developments in various industrial sectors, consider demand driven by the transport sector, and integrate hydrogen demand arising from its use in gas-powered plants. Accounting for the inherent uncertainty linked to such projections, we run the analysis for two complementary scenarios. Our approach addresses the challenges of integrating large quantities of renewable hydrogen into a future energy system by recognizing the critical role of domestic production in the early market stages. The main contribution of this work is to address the gap in optimizing hydrogen infrastructure for effective integration of domestic renewable hydrogen production in Austria by 2030, considering sector coupling potentials, optimal electrolyzer placement, and the design of local hydrogen networks.