Search Results (83)

Against the backdrop of great power strategic games, countries around the world have been continuously intensifying their control over the trade of critical metals, including tungsten, in order to seize the commanding heights of scientific, technological, and economic development, which has led to increasingly fierce competition in the global tungsten industry chain and supply chain. Although China is endowed with abundant tungsten ore reserves, its tungsten industry chain remains dominated by mid-to-low-end products, with low added value and limited pricing power in the international market. Therefore, it is of great significance to clarify the export competitiveness level of China in each link of the tungsten industry chain and to identify the influencing factors for improving the overall competitiveness of the industrial chain, which will enhance China’s international status and assist in formulating sustainable tungsten resource management strategies. Based on the industrial chain perspective and the trade data of typical products at various stages of the tungsten industry chain from 2008 to 2022, this study first selects the World Market Share Index, Trade Competitive Advantage Index, and Revealed Comparative Advantage Index to quantitatively depict the export competitiveness of the overall, upstream, midstream, and downstream sectors of China’s tungsten industry chain, and a horizontal comparison is conducted with major global tungsten resource trading countries. Secondly, the entropy weight method is adopted to further comprehensively evaluate the competitiveness level of various countries. Finally, the potential influencing factors of the overall export competitiveness of the tungsten industry chain are explored in accordance with Porter’s Diamond Model, and a fixed-effect model is used to perform regression analysis on the panel data. The research findings show that China has strong export competitiveness in the midstream and downstream sectors of the tungsten industry chain, while its export competitiveness in the upstream tungsten ore sector is relatively weak. The level of education, human capital, educational expenditure, gross national product, and trade openness all have a significant positive impact on the export competitiveness of tungsten resources. Greater efforts should be made in China to cultivate high-end talents in the tungsten industry. Moreover, innovation in green technologies and products should be encouraged, and international cooperation should be deepened, to improve the efficiency of the entire industrial chain so that stable and green long-term competitiveness in the tungsten industry can be achieved. Full article

This study investigates how the government can design optimal incentive mechanisms for Shared Battery Swapping Station (SBSS) construction enterprises under the conditions of dual information asymmetry (effort and operational efficiency) and heterogeneous corporate risk preferences. Employing game theory and principal–agent theory, this research constructs a mathematical model between the government and the enterprises to derive the optimal incentive coefficient and fixed subsidy, with theoretical results verified through numerical simulations. The findings reveal that risk-averse enterprises require higher incentives and subsidies. Compared to a single asymmetry scenario, the incentive coefficient is lower under dual information asymmetry. The government’s utility increases with an enterprise’s risk aversion beyond a critical threshold, while the enterprise’s utility remains at its reservation level. Our findings reveal a critical trade-off: while risk-averse enterprises require higher fixed subsidies and incentive coefficients, the presence of dual information asymmetry forces the government to paradoxically lower the incentive coefficient to prevent information rent extraction by less efficient firms. Furthermore, we identify a critical threshold where it becomes more beneficial for the government to contract with highly risk-averse firms due to their predictable behavior, even as the enterprise’s utility is held at its reservation level. These results provide a quantitative basis for policymakers to design a ’menu of contracts’—offering stable, high-subsidy options for risk-averse players and performance-based incentives for risk-neutral ones—rather than a one-size-fits-all policy. Full article

This study is devoted to the analysis of regional collaboration in emergency supply chain reserves. To address this critical research issue, we have developed an AI-assisted tripartite evolutionary game model involving governments, manufacturers, and suppliers across different regions under demand uncertainties and resource disparities. In this study, we employ replicator dynamic equations to derive strategic evolution paths and utilize numerical simulations enhanced by AI-powered global sensitivity analysis for subsequent parameter sensitivity analysis, enabling a systematic examination of equilibrium conditions and stability strategies. Our research findings demonstrate that when government incentive mechanisms provide greater benefits than speculative gains then supply chain enterprises evolve toward collaborative strategies, with the system achieving optimal stability at the equilibrium where collaboration benefits outweigh costs. Our AI-enhanced analysis results also reveal that while higher subsidies accelerate enterprise participation, they may reduce government motivation, necessitating carefully balanced penalty scales to sustain long-term cooperation—findings validated through sensitivity analyses of key parameters. The study’s integration of game theory with AI techniques offers both theoretical innovation in multi-agent decision modeling and practical value for strengthening national emergency management frameworks. Full article

Driven by the urgent need to decarbonize the logistics sector—where conventional vehicles exhibit high energy consumption and emissions, posing significant environmental sustainability challenges—electrification represents a pivotal strategy for reducing emissions and achieving sustainable urban freight transport. Despite rising global electric vehicle sales, the penetration rate of electric logistics vehicles (ELVs) remains comparatively low, impeding progress toward sustainable logistics objectives. Battery-swapping mode (BSM) has emerged as a potential solution to enhance operational efficiency and economic viability, thereby accelerating sustainable adoption. This model improves ELV operational efficiency through rapid battery swaps at centralized stations. This study constructs a tripartite evolutionary game model involving government, consumers, and BSM-ELV manufacturers to analyze market dynamics under diverse strategies. Key considerations include market scale, government environmental benefits, battery leasing/purchasing costs, lifecycle cost analysis (via discount rates), and resource efficiency (reserve battery ratio $\lambda$). MATLAB-2021b-based simulations predict participant strategy evolution paths. Findings reveal that market size and manufacturer expectations significantly influence governmental and manufacturing strategies. Crucially, incorporating discount rates demonstrates that battery leasing reduces consumer enterprises’ initial investment, enhancing economic sustainability and cash flow while offering superior total cost of ownership. Furthermore, gradual reduction of government subsidies effectively stimulates market self-regulation, incentivizes leasing adoption, and bolsters long-term economic/operational sustainability. Market feedback can guide policy adjustments toward fiscally sustainable support mechanisms. This study proposes the following management implications for advancing sustainable logistics: 1. Governments should phase out subsidies systematically to foster market resilience; 2. Manufacturers must invest in BSM R&D to improve efficiency and resource circularity; 3. Consumer enterprises can achieve economic benefits and emission reductions by adopting BSM-ELVs. Full article

This paper addresses the synergy between environmental and economic benefits in the green power trading market by constructing a collaborative game model for environmental rights value and electricity energy value. Based on this, a model for maximizing the benefits of flexible resource operation is proposed. Through the combination of non-cooperative and cooperative games, the conflict and synergy mechanisms of multiple stakeholders are quantified, and the Shapley value allocation rule is designed to achieve Pareto optimality. Simultaneously, considering the spatiotemporal regulation capability of flexible resources, dynamic weight adjustment, cross-period environmental rights reserve, and risk diversification strategies are proposed. Simulation results show that under the scenario of a carbon price of 50 CNY/ton (≈7.25 USD/ton) and a peak–valley electricity price difference of 0.9 CNY/kWh (≈0.13 USD/kWh), when the environmental weight coefficient α = 0.5, the total revenue reaches 6.857 × 10⁷ CNY (≈9.94 × 10⁶ USD), with environmental benefits accounting for 90%, a 15.3% reduction in carbon emission intensity, and a 1.74-fold increase in energy storage cycle utilization rate. This research provides theoretical support for green power market mechanism design and resource optimization scheduling under “dual-carbon” goals. Full article

Background/Objectives: In soccer, scanning before receiving the ball helps players better perceive and interpret their surroundings, enabling faster and more effective passes. Despite its importance, no standardized tests currently incorporate scanning actions into assessments of passing abilities. In this study, we test the reliability and validity of a battery of passing tests that assess a player’s ability to control and pass the ball while also scanning for the appropriate target. Methods: We designed three passing tests that reflect different scanning demands that are routinely placed upon players during matches. Using players from the first and reserve teams of two professional clubs in Ghana (Club A, first-team n = 11, reserve-team n = 10; Club B, first-team n = 16, reserve-team n = 17), we: (i) tested the repeatability of each passing test (intraclass correlations), (ii) assessed whether the tests could distinguish between first and reserve team players (linear mixed-effects model), and (iii) examined whether players who were better in the passing tests had higher performances in 3v1 Rondo possession games (linear models). Results: All passing tests were significantly repeatable (ICCs = 0.77–0.85). Performance was highest in the 120-degree test (30.11 ± 7.22 passes/min), where scanning was not required, and was lowest in the 360-degree test (25.55 ± 5.94 passes/min), where players needed to constantly scan behind them. When players were scanning through an arc of 180 degrees, their average performance was 27.41 ± 6.14 passes/min. Overall passing performance significantly distinguished first from reserve team players (β = −1.47, t (51) = −4.32, p < 0.001)) and was positively associated with 3v1 Rondo possession performance (R² = 0.51, p < 0.001). Conclusions: Our results show that these passing tests are reliable, distinguish players across competitive levels, and correlate with performance in possession games. These tests offer a simple, ecologically valid way to assess scanning and passing abilities for elite players. Full article

This article studies the location–price Hotelling game. Numerous studies have been conducted on the Hotelling game with simultaneous decisions; however, in real-life scenarios, decisions are frequently sequential. Unfortunately, studies on the sequential Hotelling (SHOT) game are quite scarce. This article contributes to the study of the SHOT game by considering the case in which the location of one of the players, either the leader or the follower, is externally fixed. The game is studied analytically and by numerical simulation to address scenarios where mathematical analysis is cumbersome due to the discontinuous nature of the game. Simulation is found to be particularly useful in evaluating the subgame perfect equilibrium (SPE) solution of these SHOT games, where the follower outperforms the leader as a very general rule, with very few exceptions. This article complements a previous study of the SHOT game where the two locations are parameterized and paves the way to address the analysis of more sophisticated formulations of the SHOT game, such as those with reservation cost and with elastic demand. Full article

Ecological determinants of avian population dynamics are essential for effective wildlife management and conservation. Black and grey francolins are classified as being of least concern by the IUCN and are an ecologically significant bird in the northern regions of Pakistan. Although habitat degradation and overhunting have adversely affected their populations, research on the population structure and habitat preferences of the Totali Game Reserve, Buner District, Pakistan, remains limited. The present study applied distance sampling via the line transect method to estimate population densities and the quadrat method to assess vegetation characteristics across three distinct habitats. A statistical analysis revealed significant variations in densities across the three habitat types—agricultural lands, agroforests, and pasturelands—with both species exhibiting distinct preferences for pastureland ecosystems. Seasonal trends indicated that autumn represented the peak period for the population, driven by post-breeding surges and optimal habitat conditions. Moreover, both species demonstrated a strong affinity for habitats dominated by specific plant species, including hopbush, raspberry, barberry, and blackberry, which provide a critical resource for food, foraging, nesting, and shelter. These findings highlight the ecological importance of pasturelands and specific vegetation types for supporting the survival of these species. Furthermore, conservation efforts should prioritize the preservation and restoration of pastureland ecosystems and incorporate rigorous monitoring programs to guide adaptive management strategies aimed at mitigating population declines. Full article

In order to improve the trading efficiency of virtual power plants (VPPs) participating in the market of multi-type auxiliary services under the gaming environment, an initial trading price setting method based on the information of VPPs’ response characteristics and real-time supply and demand changes is proposed to accelerate the convergence speed of the game. Firstly, a master–slave game trading model is established based on the reference auxiliary service pricing, which consists of a tariff coefficient and a basic tariff. Secondly, the tariff coefficient model is constructed based on response information, including response rate, quality, and reliability. Again, the basic tariff model is constructed based on the real-time supply and demand situation and the real-time grid tariff. Finally, the effectiveness of the proposed method in accelerating the convergence speed of the game is verified by analyzing 12 VPPs under the three auxiliary service scenarios of peaking, frequency regulation, and reserve. Full article

(1) Background: Limited information on Echinococcus species among the wildlife in Tanzania has created a significant knowledge gap regarding their distribution, host range, and zoonotic potential. This study aimed to enhance the understanding of Echinococcus felidis transmission dynamics within the great Serengeti ecosystem. (2) Methods: A total of 37 adult Echinococcus specimens were collected from a leopard (Panthera pardus) (n = 1) in Maswa Game Reserve and 7 from a lion (Panthera leo) (n = 1) in Loliondo. Two hydatid cysts were also obtained from warthogs (n = 2) in the Serengeti National Park. (3) Results: Morphological examination revealed infertile cysts in warthogs that were molecularly identified as E. felidis. This marks the first molecular evidence of E. felidis in leopards and warthogs in Tanzania. Pairwise similarity analysis showed 98.7%–99.5% identity between Tanzanian, Ugandan, and South African isolates. Thirteen unique haplotypes were identified, with a haplotype diversity of (Hd = 0.9485) indicating genetic variability. Phylogenetic analysis grouped E. felidis into a single lineage, with the leopard isolate forming a distinct haplotype, suggesting leopards as an emerging host. Lion and warthog isolates shared multiple mutational steps, suggesting possible genetic divergence. (4) Conclusions: This study confirms African lions and leopards as definitive hosts and warthogs as potential intermediate hosts of E. felidis in the Serengeti ecosystem. Our findings highlight disease spillover risks and stress the importance of ecosystem-based conservation in wildlife–livestock overlap areas. Although E. felidis is believed to be confined to wildlife, the proximity of infected animals to pastoralist communities raises concerns for spillover. These findings highlight the importance of ecosystem-based surveillance, especially in wildlife–livestock–human interface areas. Full article

Clock synchronization, as the fundamental service in the power grid, provides a unified time standard for all kinds of power services, such as metering, controlling, and scheduling. Since massive new energy devices are connected to the power grid, they bring new demands for differentiated synchronization accuracy and dynamic access synchronization. Considering the limited communication resources of the power grid, we propose a master–slave clock synchronization method based on the two-layer Stackedberg game to satisfy the synchronization demand by diverse devices as much as possible. First, the master station dynamically prices users based on the required synchronization accuracy and the number of synchronous devices, creating a game process between users. Secondly, an iterative algorithm for solving game equilibrium is designed. Finally, the simulation results are given in MATLAB to prove that the proposed method can converge quickly and dynamically adjust allocation according to user demand. Furthermore, the network simulator Mininet and the open-source software-defined network framework Ryu are used to evaluate the performance of the proposed method. Compared with the bandwidth reservation scheme, our proposed method is more suitable for differentiated clock synchronization of resource-limited new energy power networks. This paper investigates the impact of network capacity changes on the clock synchronization accuracy of user equipment in power networks for the first time. Then, a two-layer Stackedberg game model has emerged to achieve optimal bandwidth allocation in the network and improve clock synchronization accuracy. Simulation results show that our method can not only meet the differentiated clock synchronization requirements but also achieve the optimal allocation in dynamic access scenarios. Full article

Effective and sustainable water reserve management faces increasing challenges due to climate-induced variability, data fragmentation, and the limitations of traditional, static modeling systems. This study introduces a conceptual framework designed to address these challenges by integrating digital twins, IoT-driven real-time monitoring, game engine simulations, and AI-driven decision support systems (AI-DSS). The methodology involves constructing a digital twin ecosystem using IoT sensors, GIS layers, remote-sensing imagery, and game engines. This ecosystem simulates water dynamics and assesses policy interventions in real time. AI components, including machine-learning models and retrieval-augmented generation (RAG) chatbots, are embedded to synthesize real-time data into actionable insights. The framework enables the continuous assessment of hydrological dynamics, predictive risk analysis, and immersive, scenario-based decision-making to support long-term water sustainability. Simulated scenarios demonstrate accurate flood forecasting under variable rainfall intensities, early drought detection based on soil moisture and flow data, and real-time water-quality alerts. Digital elevation models from UAV photogrammetry enhance terrain realism, and AI models support dynamic predictions. Results show how the framework supports proactive mitigation planning, climate adaptation, and stakeholder communication in pursuit of resilient and sustainable water governance. By enabling early intervention, efficient resource allocation, and participatory decision-making, the proposed system fosters long-term, sustainable water security and environmental resilience. This conceptual framework suggests a pathway toward more transparent, data-informed, and resilient decision-making processes in water reserves management, particularly in regions facing climatic uncertainty and infrastructure limitations, aligning with global sustainability goals and adaptive water governance strategies. Full article

The reserves of hot dry rock (HDR) geothermal resources are huge. The main method used to develop HDR geothermal resources is called an enhanced geothermal system (EGS), and this generally uses hydraulic fracturing. After nearly 50 years of research and development, more and more countries have joined the ranks engaged in the exploration and development of HDR in the world. This paper summarizes the base technologies, key technologies, and game-changing technologies used to promote the commercialization of HDR geothermal resources. According to the present situation of the exploration, development, and utilization of HDR at home and abroad, the evaluation and site selection, efficient and low-cost drilling, and geothermal utilization of HDR geothermal resources are defined as the base technologies. Key technologies include the high-resolution exploration and characterization of HDR, efficient and complex fracture network reservoir creation, effective microseismic control, fracture network connectivity, and reservoir characterization. Game-changing technologies include downhole liquid explosion fracture creation, downhole in-situ efficient heat transfer and power generation, and the use of CO₂ and other working fluids for high-efficient power generation. Most of the base technologies already have industrial applications, but future efforts must focus on reducing costs. The majority of key technologies are still in the site demonstration and validation phase and have not yet been applied on an industrial scale. However, breakthroughs in cost reduction and application effectiveness are urgently needed for these key technologies. Game-changing technologies remain at the laboratory research stage, but any breakthroughs in this area could significantly advance the efficient development of HDR geothermal resources. In addition, we conducted a comparative analysis of the respective advantages of China and the United States in some key technologies of HDR development. On this basis, we summarized the key challenges identified throughout the discussion and highlighted the most pressing research priorities. We hope these technologies can guide new breakthroughs in HDR geothermal development in China and other countries, helping to establish a batch of HDR exploitation demonstration areas. In addition, we look forward to fostering collaboration between China and the United States through technical comparisons, jointly promoting the commercial development of HDR geothermal resources. Full article

Limited research exists on the breeding ecology of the black francolin (Francolinus francolinus) in northern Pakistan. This study assessed egg dimensions, clutch size, hatching, fledging, and overall breeding success across different habitats and nests (n = 25) at Totali Game Reserve, Buner. Generalized linear models (GLMs) were used to analyze the effects of nest site characteristics and nest traits on breeding parameters. Egg dimensions were consistent across sites whereas bush nests had slightly wider eggs. The average clutch size was 5.9 ± 1.7 eggs, with an average of 4.8 ± 1.0 hatchlings per nest. A total of 111 chicks fledged, averaging 4.4 ± 1.0 per nest, yielding an overall breeding success rate of 75.5%. Nests containing six eggs had higher hatching success (76.6%). GLMs results showed a significant positive relationship between clutch size and hatchling, while nest site and traits had no significant effects. However, fledgling success was positively influenced by hatchling numbers, with nests in wetland habitats yielding significantly more fledglings (4.6 ± 0.9) than those from dryland habitats (4.0 ± 1.2). These findings suggest Black Francolins prefer nesting in wetland areas in bushes, likely due to better protection and favorable conditions. Full article

The Calakmul Biosphere Reserve (CBR) is in the south of the Yucatán Peninsula and is known for its great biological diversity. However, despite the great diversity of species, they are under intense pressure from hunting activities, especially the larger ones that can be used for human food. Therefore, the objective of this study was to obtain knowledge about the hunting importance of populations of three species of birds (Crax rubra, Meleagris ocellata, and Penelope purpurascens) in the southern zone of the Calakmul Biosphere Reserve, Campeche. Sampling was conducted with transects where a total of 46 camera traps were installed from November 2021 to November 2022, distributed in two types of vegetation. Likewise, data on species presence were collected and analyzed with Principal Component Analysis and ANOSIM (ANOSIM; R = 0.10, p = 0.22) to relate abundances with vegetation types and seasons of the year. No significant differences were found between the two vegetation types. This study provides relevant information on the populations of game birds in the southern region of Calakmul, which is currently little explored, and constant monitoring of these species throughout the CBR is necessary. Full article