Search Results (169)

Public–private partnership (PPP) logistics infrastructure projects have become increasingly prevalent globally. Consequently, the effective management of these projects as their concession periods expire presents a crucial challenge for governments, vital for the sustainable management of PPP logistics infrastructure. This study addresses this challenge by focusing on the pivotal post-concession decision: whether the government should self-operate the mature logistics infrastructure or re-delegate its management to a private entity. Our theoretical model, built on a principal–agent framework, first establishes a social welfare baseline under government self-operation and then analyzes delegated operation under symmetric information, identifying efficiency frontiers. Under symmetric information, we find that government self-operation is more advantageous when its own operational efficiency is sufficiently high, irrespective of the private enterprise’s efficiency; conversely, delegating to an efficient private enterprise is optimal only when government operational efficiency is low. We also demonstrate that if the government can directly specify the demand quantity and service level and delegates operation via a fixed fee, the enterprise can be incentivized to align with the social optimum. However, under asymmetric information, potential welfare gains from delegation are inevitably offset by informational rent and output distortion. We further uncover non-monotonic impacts of parameters like the proportion of low-cost firms on social welfare loss and demonstrate how information asymmetry can indirectly compromise the long-term resilience of the infrastructure. Ultimately, our work asserts that delegation is only superior if its potential efficiency gains sufficiently offset the inherent losses stemming from information asymmetry. Full article

Technological roadmaps are essential tools for managing and planning complex projects, especially in the rapidly evolving field of space exploration. Defined as dynamic schedules, they support strategic and long-term planning while coordinating current and future objectives with particular technology solutions. Currently, the available methodologies are mostly built on experts’ opinions and in just few cases, methodologies and tools have been developed to support the decision makers with a rational approach. In any case, all the available approaches are meant to draw “ideal” maturation plans. Therefore, it is deemed essential to develop an integrate new algorithms able to decision guidelines on “non-nominal” scenarios. In this context, Politecnico di Torino, in collaboration with the European Space Agency (ESA) and Thales Alenia Space–Italia, developed the Technology Roadmapping Strategy (TRIS), a multi-step process designed to create robust and data-driven roadmaps. However, one of the main concerns with its initial implementation was that TRIS did not account for time and budget estimates specific to the space exploration environment, nor was it capable of generating alternative development paths under constrained conditions. This paper discloses two main significant updates to TRIS methodology: (1) improved time and budget estimation to better reflect the specific challenges of space exploration scenarios and (2) the capability of generating alternative roadmaps, i.e., alternative technological maturation paths in resource-constrained scenarios, balancing financial and temporal limitations. The application of the developed routines to available case studies confirms the tool’s ability to provide consistent planning outputs across multiple scenarios without exceeding 20% deviation from expert-based judgements available as reference. The results demonstrate the potential of the enhanced methodology in supporting strategic decision making in early-phase mission planning, ensuring adaptability to changing conditions, optimized use of time and financial resources, as well as guaranteeing an improved flexibility of the tool. By integrating data-driven prioritization, uncertainty modeling, and resource-constrained planning, TRIS equips mission planners with reliable tools to navigate the complexities of space exploration projects. This methodology ensures that roadmaps remain adaptable to changing conditions and optimized for real-world challenges, supporting the sustainable advancement of space exploration initiatives. Full article

Waste-to-energy (WtE) are clean technologies that support a circular economy by providing solutions to managing non-recyclable waste while generating alternative energy sources. Despite the promising benefits, technology adoption is challenged by financing constraints, technical maturity, environmental impacts, supporting policies, and public acceptance. A growing number of studies analyzed the acceptability of WtE and identified the factors affecting the adoption of WtE technologies. This study aims to analyze these research hotspots, technologies, and acceptability factors by combining bibliometric and systematic analyses. An initial search from the Web of Science and Scopus databases identified 817 unique documents, and the refinement resulted in 109 for data analysis. The results present a comprehensive overview of the state-of-the-art, providing researchers a basis for future research directions. Among the WtE technologies in the reviewed literature are incineration, anaerobic digestion, gasification, and pyrolysis, with limited studies about refuse-derived fuel and landfilling with gas recovery. The identified common factors include perceived risks, trust, attitudes, perceived benefits, “Not-In-My-BackYard” (NIMBY), awareness, and knowledge. Moreover, the findings present valuable insights for policymakers, practitioners, and WtE project planners to support WtE adoption while achieving sustainable, circular, and low-carbon economies. Full article

The increasing demand for efficient, sustainable, and coordinated construction practices has intensified interest in the integration of digital tools such as Building Information Modelling (BIM) with modularization and standardization strategies. This study aims to examine the relationship among BIM maturity levels, modularization grades, and standardization levels, and to assess their combined impact on construction project outcomes. A mixed-methods approach, including a systematic literature review and New Zealand-based case studies, is used to develop and validate an evaluative framework. The SLR identifies key themes and determinants, while the case studies provide empirical evidence on the interactions between BIM maturity levels, modularization grades, and standardization levels. The study identifies that higher BIM maturity levels significantly enhance modularization and standardization practices. Advanced BIM capabilities foster improved design coordination, collaboration, and data management, leading to more efficient construction processes. A guideline for mapping BIM maturity against standardization levels is proposed to assist stakeholders in evaluating and optimizing project outcomes. This research offers a novel perspective on integrating BIM maturity with modularization and standardization practices. While it is applied in the New Zealand context, the proposed framework and methodology are designed to be transferable to international settings. It provides actionable insights for policymakers and industry stakeholders seeking to refine standards, promote BIM adoption, and enhance construction project efficiency worldwide. Full article

The European Union (EU) is advancing a digital twin of its electricity grid as a flagship initiative to accelerate the dual transitions of decarbonization and digitalization. By creating a real-time virtual replica of the EU-27 power network, policymakers and industry stakeholders aim to enhance grid efficiency, resilience, and renewable energy integration. This review provides a comprehensive analysis of the three critical dimensions shaping the digital twin’s development: (1) regulatory barriers, including fragmented policies, inconsistent data governance frameworks, and the need for harmonized standards and incentives across member states; (2) technological challenges, such as achieving interoperability, integrating real-time data, developing robust cybersecurity measures, and ensuring scalable infrastructure; and (3) economic opportunities, centered on potential cost savings, optimized asset management, new flexibility services, and pathways for innovation and investment. Drawing on European Commission policy documents, regulatory reports, academic studies, and industry projects like the Horizon Europe TwinEU initiative, this review highlights that significant groundwork has been laid to prototype and federate local grid twins into a cohesive continental system. However, achieving the full potential of a pan-European digital twin will require additional regulatory harmonization, more mature data-sharing protocols, and sustained financial commitment. This review concludes with an outlook on the strategic convergence of policy reforms, collaborative R&D, and targeted funding, emphasizing how institutional momentum, federated architectures, and cross-sector integration are advancing a secure, resilient, and economically viable digital twin that is envisioned as a foundational layer in the operational and planning infrastructure of Europe’s future electricity system. Full article

The uncontrolled urbanization of Brazilian cities accentuates the imbalance between population demands and urban space planning. The integrated management of human and technological resources constitutes a fundamental governance strategy for the proposition of sustainable and effective responses to the challenges faced by cities. To generate references to public management, the objective of this research was to develop a management tool to verify the maturity level of Brazilian cities for smart city actions. A performance measurement system (PMS) organized smart city actions into 11 thematic areas, quantitatively measuring smart city actions in a down–top structure since the indicators and metrics are described in a standardized scale to obtain the general maturity index (GMI). The PMS was implemented in the city of Santa Maria/Brazil, where its GMI equal to 43.72% indicated a currently intermediate maturity level of smart city actions, mainly related to the low performance in the thematic areas of mobility, coexistence and reciprocity, and security and protection. To improve the current performance, five incremental actions were proposed, contemplating the key performance indicators “Public roads”, “Multipurpose lanes”, “Public accessibility”, “Accessibility signage”, and “Monitoring”, projecting a GMI equal to 49.75% and 55.78%, respectively, for an intermediate and an advanced maturity level scenario. Full article

This paper explores the evolving relationship between Digital Twins (DT) and the Metaverse, two foundational yet often conflated digital paradigms in digital architecture. While DTs function as mirrored models of real-world systems—integrating IoT, BIM, and real-time analytics to support decision-making—Metaverses are typically fictional, immersive, multi-user environments shaped by social, cultural, and speculative narratives. Through several research projects, the team investigate the divergence between DTs and Metaverses through the lens of their purpose, data structure, immersion, and interactivity, while highlighting areas of convergence driven by emerging technologies in Artificial Intelligence (AI) and Extended Reality (XR).This study aims to investigate the convergence of DTs and the Metaverse in digital architecture, examining how emerging technologies—such as AI, XR, and Large Language Models (LLMs)—are blurring their traditional boundaries. By analyzing their divergent purposes, data structures, and interactivity modes, as well as hybrid applications (e.g., data-integrated virtual environments and AI-driven collaboration), this study seeks to define the opportunities and challenges of this integration for architectural design, decision-making, and immersive user experiences. Our research spans multiple projects utilizing XR and AI to develop DT and the Metaverse. The team assess the capabilities of AI in DT environments, such as reality capture and smart building management. Concurrently, the team evaluates metaverse platforms for online collaboration and architectural education, focusing on features facilitating multi-user engagement. The paper presents evaluations of various virtual environment development pipelines, comparing traditional BIM+IoT workflows with novel approaches such as Gaussian Splatting and generative AI for content creation. The team further explores the integration of Large Language Models (LLMs) in both domains, such as virtual agents or LLM-powered Non-Player-Controlled Characters (NPC), enabling autonomous interaction and enhancing user engagement within spatial environments. Finally, the paper argues that DTs and Metaverse’s once-distinct boundaries are becoming increasingly porous. Hybrid digital spaces—such as virtual buildings with data-integrated twins and immersive, social metaverses—demonstrate this convergence. As digital environments mature, architects are uniquely positioned to shape these dual-purpose ecosystems, leveraging AI, XR, and spatial computing to fuse data-driven models with immersive and user-centered experiences. Full article

The incorporation of climate refugia concepts in large-scale protection efforts (e.g., 30% protected by 2030, 50% by 2050) is needed to forestall the global extinction crisis. The 8.19 M ha Northern Rockies Ecoregion (NRE) of western Montana, northeastern Washington, and northern Idaho, USA, includes the 159,822 Yaak River Watershed (YRW) in northwest Montana, a proposed climate refugium that may buffer extreme climate change effects. Climate projections show temperature increases along with reduced summer precipitation, lowered spring snowpack, and increased wildfire susceptibility across the NRE but to a lesser extent in the YRE under an intermediate emissions scenario. Overall protection levels were quite low in the NRE (2.2% in GAP 1 or 2) and even lower in the YRW (1% of national forests; the USDA Forest Service manages most of the area). Approximately 32% of forests are mature but only 2.4% and 0.25% are protected (GAP 1 or 2) within the NRE and YRW, respectively. Habitat protection levels for eight focal forest species selected to reflect conservation priorities were generally low, with only wolverine (Gulo gulo) meeting conservation targets if roadless areas were better protected. Most (~75%) Forest Service fuel reduction treatments were >1 km from structures despite congressional funds aimed at the wildland–urban interface/intermix. Increased roadless area protections would close the lower bound (30%) target for most ecosystem types and focal species but still fall short of upper targets. We recommend coupling conservation targets with strategic investments in fuel reductions aimed at the innermost buffer around structures, while reducing logging and roadbuilding in priority areas and refugia. Full article

Within the Life-NADAPTA project (LIFE16 IPC/ES/000001), and in the framework of sustainable waste management, a study was carried out on the microbiological evolution during the composting process of the organic fraction of municipal solid waste (FORSU) using aerated static piles and their agricultural application on a pilot scale. This is necessary to ensure effective sanitization of the compost and that its application does not pose any risk. The microbiological parameters considered were as follows: Salmonella sp., Escherichia coli, total coliforms, and Enterococcus sp. The physicochemical parameters moisture, total solids, organic matter, nitrogen, phosphorus, and heavy metals were also evaluated. Salmonella sp. was not detected throughout the process, and the concentration of the three microbiological indicators decreased to the sanitary conditions recommended by legislation. As a result, the compost obtained complied with the requirements set out in the regulations on fertilizer products and was highly stabilized and mature for application on agricultural land. Tests were carried out on the soil before, during and after the vegetative cycle of the crop and on the irrigation water. The soil results showed that the addition of the organic amendment did not alter the populations of the tested micro-organisms at the end of the crop growing cycle. Thus, an adequate treatment of the residues allows them to be used in a sustainable way, but an adequate monitoring of the operational parameters is necessary to ensure this. Full article

Space is one of the UK’s fastest-growing industry sectors of the last decade. Recognising this, in 2021 the UK Government’s first National Space Strategy established a new vision to make the nation one of the most innovative and attractive worldwide space economies. As part of the strategic funding programme, in 2023, the UK Space Agency (UKSA) funded a scoping study to assess the potential of satellite data to address issues that the three North East England Local Resilience Forums face at all stages of implementing the UK’s Integrated Emergency Management Framework (IEMF). Through dedicated workshops convened by two North East England universities, regional stakeholders from the emergency domain and related industries identified three case studies ripe for applying satellite data in support of multi-agency IEMF activities. Master’s students in the UK’s Centre for Doctoral Training in Geospatial Systems then undertook a month-long integrated group project to assess the potential for satellite imagery to be applied in the identified application areas. The research reported in this paper demonstrates how satellite imagery may be adopted to help address challenges posed during power outages, for mitigating illegal waste site fires, and during periods of snow and extreme cold. While the maturity levels of satellite applications vary in the three case studies due to data availability and image resolution, all three cases demonstrate that space data, particularly when augmented with additional geospatial information, help to enhance IEMF analysis. It is anticipated that the findings from the study will help stakeholders involved in IEMF management appreciate the added value of integrating satellite data into their current processes and analyses. By empowering key stakeholders to use satellite applications more effectively, it is predicted that better decisions will be achieved, thereby improving emergency risk management. A prototype dashboard, an output of the research to demonstrate the potential of space data for emergency management, is available online. Full article

Forest structural diversity, referring to the variety of physical structural traits, has been identified as a critical indicator of both plant species and environmental diversity. Mapping structural diversity serves as a cost-effective proxy for monitoring forest biodiversity and large-scale ecosystem functions like productivity. Light detection and ranging (LiDAR) carried by unmanned aerial vehicles (UAVs) can achieve precise quantification of structural parameters with a resolution of sub-meter at the stand scale, providing robust support for accurately depicting three-dimensional forest structural features. Since forest management influences biodiversity and ecological functions by shaping the physical structure of forests, this study investigates how different forest management strategies affect structural diversity in China’s red soil hilly region. Using point cloud data obtained by unmanned aerial vehicle laser scanning (UAV-LS), we derived structural metrics including canopy volume diversity (CVD), and tree height diversity (THD), which were then used as variables to calculate the Shannon diversity index (SDI) of forests. The study focused on three forest types: close-to-nature broadleaf forest (CNBF), coniferous mature plantations (CPM), and close-to-nature coniferous forest (CNCF). Results revealed that CNBF exhibited the highest structural diversity, with superior values for canopy volume (CVD = 2.09 ± 0.35), tree height (THD = 1.72 ± 0.53), and canopy projected area diversity (CAD = 2.13 ± 0.32), approaching the upper range of the theoretical maximum for SDI (theoretical maximum ≈ 2.3; typical range: 0.5–2.0). This was attributed to optimal understory vegetation and higher biomass. Despite exhibiting greater tree height, CPM demonstrated lower structural diversity, while CNCF recorded a CVD (1.81 ± 0.39) similar to that of CPM but lower than that of CNBF. These results indicate that close-to-nature forest management enhances forest structural diversity. It is implied that the forest structural diversity can serve as an effective tool for evaluating forests biodiversity under different forest management strategies. The study also suggests that improving understory vegetation is a direction in the future management of coniferous plantations. Full article

Mongolian pine (Pinus sylvestris var. Mongolia) has been widely utilized as a key species for afforestation projects within the Three-North Shelterbelt of Liaoning Province in China. Its impressive ecological resilience has made it a favorite choice for this endeavor. However, as the stands mature and climate conditions shift, some areas are experiencing premature decline or even mortality. Ecological stoichiometry is capable of uncovering the supply and equilibrium of plant and soil nutrients within ecosystems and is extensively utilized in the identification of limiting elements. Therefore, studying its ecological stoichiometry and internal stability dynamics is of crucial significance for clarifying the nutrient cycling process in the Mongolian pine region and alleviating the decline situation. The eastern and northwestern regions of Liaoning differ significantly in precipitation and soil nutrient availability. This study examines Mongolian pine plantations in both regions, analyzing the carbon (C), nitrogen (N), and phosphorus (P) content in plant tissues, soil, microbial biomass, and stoichiometric ratio under distinct environmental conditions. In order to provide a theoretical basis for alleviating the decline of artificial poplar forests and healthy management. Results indicate that (1) leaf C, N, and P contents in the eastern Liaoning region averaged 496.67, 15.19, and 1.66 g·kg⁻¹, respectively, whereas those in northwestern Liaoning were 514.16, 14.82, and 1.23 g·kg⁻¹, respectively. Soil C, N, and P concentrations exhibited notable regional differences, with eastern Liaoning recording 34.54, 2.62, and 0.48 g·kg⁻¹, compared to significantly lower values in northwestern Liaoning (7.74, 0.77, and 0.21 g·kg⁻¹). Similarly, microbial biomass C, N, and P were higher in eastern Liaoning (18.63, 5.09, and 7.72 mg·kg⁻¹) than in northwestern Liaoning (10.18, 3.46, and 4.38 mg·kg⁻¹). (2) The stoichiometric ratio of soil in the Mongolian pine plantations is higher than that in northwestern Liaoning, but the stoichiometric ratio of plants shows the opposite trend. Specifically, microbial carbon-to-nitrogen (MBC/MBN) ratios are higher in eastern Liaoning, whereas microbial carbon-to-phosphorus (MBC/MBP) and nitrogen-to-phosphorus (MBN/MBP) ratios are greater in northwestern Liaoning. Correlation analysis of plant–soil–microbe stoichiometry indicates that plant growth in both regions is co-limited by nitrogen, with Mongolian pine exhibiting strong internal stability. Full article

With the increased electrification of aircraft, the thermal management of associated heat loads becomes more and more of a challenge. While a classical airline aircraft typically has a system thermal emission in the same range as the heat generated by passengers, more innovative hybrid electric aircraft designs and hydrogen-powered aircraft can require up to 1 MW of cooling, which is two orders of magnitude larger than the heat load of the transported passengers. For the development of such systems, dedicated laboratory test environments are necessary to pre-assess technologies and flight conditions in research and maturation projects. The Flight Test Facility is one such facility, and this paper will outline some of the thermal tests performed in the past and planned enhancements of the testing capabilities. Full article

Building Information Modeling (BIM) has recently gained popularity in the public building industry, and BIM is widely implemented in the construction industry in many developed countries around the world. In this paper, in order to evaluate the application level of BIM technology in assembly buildings in China, five maturity levels of BIM application in assembly buildings are established based on the commonly used maturity model, including the initial level, the starting level, the management level, the integration level, and the continuous optimization level. In order to construct a maturity evaluation index system for BIM application in prefabricated buildings, the literature review method was chosen to identify the indexes initially, the indexes were optimized by combining the questionnaire survey method, and using the balanced scorecard model, the maturity evaluation index system for BlM application in prefabricated buildings consisting of one target level, five guidance levels, thirteen graded element levels and thirty-one secondary index levels were identified. Based on this framework, the study establishes a maturity assessment model for BIM application in prefabricated buildings through three methodological integrations. First, the hierarchical analysis method Analytic Hierarchy Process (AHP) was employed to assign weights to indexes within the evaluation system. Subsequently, the Entropy Weight Method (EWM) was utilized to systematically construct the index system. This quantitative foundation was then combined with fuzzy comprehensive evaluation principles to develop the integrated assessment model. The practical application of this model was demonstrated through a case study of a prefabricated building project in China. The assessment results revealed that the project’s BIM application maturity level falls within the transitional phase “between the management level and integrated level”, indicating progressive but not yet fully optimized implementation. The result verifies the validity of the assessment model and proposes corresponding optimization suggestions based on the assessment results. Full article

This research aims to develop and validate an organizational maturity framework (OM framework) to assess an organization’s maturity and improve the operational performance of the EQM. The study adopts a multi-methods approach. Qualitative data are sourced from 18 respondents and analyzed through thematic analysis. The analysis reveals that pollution control and energy efficiency are the primary EQM concerns. The maturity assessment occurs through data from one or multiple sources, with the most preferred models being the five-phase models. Finally, maturation has diverse effects on EQM, which mirrors continuous improvement expectations. The quantitative study involved 212 respondents drawn from PBOs across the country. The data were analyzed through SEM, culminating in hypothesis testing. Three of the eight hypotheses were supported, including H4: Legal requirements have a statistically significant impact on PBO maturity (β = −0.150, p = 0.015); H5: Sustainability has a positive statistically significant impact on PBO maturity (β = 0.169, p = 0.045); and H1: the level of maturity determines efficiency in EQM (β = 0.066, p = 0.050). The rest of the variables have an inverse relationship or effects that are not statistically significant. The assessment of weightings for the determinants of PBO maturity culminates in the realization that the variables whose hypothesized relationships were confirmed received moderate priority. These findings explain why the determinants of PBO maturity only explain 8.8% of the variance in maturity, while the entire model explains only 3% of the EQM efficiency. The findings culminate in the validity of the operational instructions for improvement in the task specificity of PBO maturity for EQM performance and an improvement in the conceptualization of EQM efficiency among the PBOs. Full article