Search Results (971)

This study develops exact analytical solutions for transient elliptical groundwater flow toward an extended well in an anisotropic fractured confined aquifer and then discusses how the resulting hydraulic response can support groundwater-head interpretation in shale-gas development areas. The environmental connection is made at the aquifer-protection scale: the model is not a shale-gas reservoir production model, and it does not solve contaminant transport directly. Instead, it provides a hydraulic interpretation framework for estimating anisotropy, equivalent fracture length, wellbore-storage effects, and the preferential direction of head propagation around possible leakage points, old wells, fractures, or monitoring wells. Based on Mathieu-function theory and the separation-of-variables method, constant-rate and constant-head solutions are derived in Laplace space and inverted to the time domain with the Stehfest algorithm. The analytical results are validated against COMSOL5.2 finite-element simulations, and the effects of anisotropy coefficient and wellbore storage are analyzed through drawdown and flow-rate type curves. A synthetic but field-style water-head example is included to demonstrate how monitoring records can be converted to drawdown, fitted to the elliptical-flow solution, and used to delineate a preliminary hydraulic response zone. The results show that anisotropy mainly controls early-to-middle time response, whereas wellbore storage may obscure early head changes and delay the recognition of fracture connectivity. Therefore, the solution is best regarded as a rapid hydraulic-screening and monitoring-design tool that can precede, but not replace, site-specific contaminant-transport modeling in shale-gas groundwater-protection studies. The relevant technical issues are possible head disturbances and preferential groundwater pathways associated with surface spills, flowback-water handling, old wells, faults, and fracture-connected water-bearing zones. Because verified local field-monitoring records were not available for us, the application example is explicitly described as a synthetic field-style demonstration; it is used to show the workflow and its limitations, not to claim site-specific prediction of contaminant concentration. Full article

In Indian religious traditions, pātāla denotes a seven-layered subterranean realm beneath the earth, a composite space that combines cosmological stability with mythic expressiveness. It serves as the dwelling of nāgas and asuras and connects with the human world through rivers and caves. Although Buddhist literature retains narratives about these beings and their splendid abodes, it never accepted pātāla as an independent cosmological unit. This article examines Pāli, Chinese, Tibetan, and Sanskrit Buddhist sources in comparison with Hindu epic and Purāṇic literature and analyzes the translation of pātāla in Chinese versions. It argues that Buddhism engaged in selective restructuring by de-emphasizing pātāla’s cosmological hierarchy and subordinating it to the Mount Sumeru framework, while transforming it in esoteric ritual literature into a liminal field of practice accessible through mantra, mudrā, and specific practices. Utilizing Arnold van Gennep’s liminality theory, the study shows that these spaces serve as an intermediary ritual field in Buddhist practice. Through ritual separation, liminal experience, and reintegration, practitioners acquire extended lifespan and merit that support the Mahāyāna goal of perfecting the two accumulations and attaining Buddhahood. The findings suggest that religious concepts cross traditions through disassembly, detachment, and functional reconfiguration rather than wholesale transplantation. Full article

The rapid development of high-density cities has triggered severe ecological challenges, including habitat fragmentation, urban heat island (UHI) effects, and conflicting demands for public recreation. Traditional ecological networks (ENs) often focus only on “source” landscapes while neglecting degraded “sink” areas. This bias limits the ability of planners to resolve complex spatial conflicts. Therefore, the primary aim of this study is to develop a robust spatial planning framework that mitigates urban ecological conflicts and enhances regional resilience. To achieve this, we constructed a composite ecological network (CEN) for the high-density city of Guangzhou that harmonizes bird habitat conservation, thermal regulation, and cultural recreation. We combined the MaxEnt model, morphological spatial pattern analysis (MSPA), and circuit theory to identify functional “sources” and “sinks” across these three dimensions. Next, using complex network theory, we optimized the CEN and evaluated its structural robustness using low degree addition (LDA) and low betweenness addition (LBA) strategies. The results indicate the following: (1) The CEN effectively captured the complex mosaic landscape of the city. (2) Single-objective networks displayed distinct spatial differences—the recreational network formed a dispersed web of 242 corridors, while habitat and climate networks remained highly clustered. (3) The integrated CEN generated 1137 multi-layered corridors, creating a vital green skeleton to support species dispersal, mitigate UHI effects, and improve cultural access. (4) Optimization simulations verified that the LBA strategy provided the highest stability against targeted attacks by balancing network connectivity with local aggregation. Ultimately, this framework offers a highly adaptable planning tool for dense cities, providing precise spatial guidance to overcome ecological bottlenecks and harmonize urban growth with ecosystem resilience. Full article

The interplay between special functions and geometric function theory continues to inspire significant advances in the study of analytic and multivalent functions. In this work, we introduce and investigate several new subfamilies of multivalent functions associated with the generalized Mittag-Leffler-type Poisson distribution in the open unit disk. We establish necessary and sufficient conditions characterizing membership in these classes and derive meaningful inclusion relationships among them. Furthermore, we define a novel integral operator linked to the generalized Mittag-Leffler-type Poisson distribution and examine its mapping properties and structural connections with the proposed function classes. The results presented herein not only unify and extend a variety of earlier contributions but also demonstrate the effectiveness of distribution-theoretic methods in the analysis of multivalent functions. Full article

The sustainable development of forest ecotourism relies on the effective stimulation of tourists’ environmentally responsible behavior, and the intervention of participatory art and aesthetics provides a new driving force for this process. Taking Xiqiaoshan National Forest Park (Nanhai Land Art Festival) as a case study, we propose an extended stimulus–organism–response (S-O-R) theoretical framework to reveal the psychological perception and transmission mechanism of participatory art and aesthetic experience in empowering the sustainable development of ecotourism. We used a hybrid approach combining PLS-SEM and artificial neural networks (ANNs) to analyze survey data from 596 Chinese tourists. The study found that sensory impressions driven by art and aesthetics significantly and positively influence tourists’ natural connections, perceived value, and ecotourism attitudes. These three constructs function as significant parallel mediators between sensory impressions and environmentally responsible behavior, while chain mediation effects are statistically significant but of small magnitude. The new environmental paradigm (NEP), conceptualized as an individual trait boundary condition, exhibits a significant negative moderating effect on the relationship between sensory impressions and connectedness to nature. ANN sensitivity analysis further complements the findings by demonstrating the prominent nonlinear predictive role of ecotourism attitudes in behavioral transformation. This study extends the application boundaries of the S-O-R theory to art-integrated ecotourism research, clarifies the internalization process of tourist experiences from sensory perception to behavioral enactment, and provides empirical evidence for forest tourism managers to optimize experience design and implement differentiated guidance strategies. Full article

This study aimed to characterize cortical dysfunction and frequency-specific network reorganization following optic nerve injury using spin-exchange relaxation-free magnetoencephalography (SERF-MEG), and to assess the potential of MEG-derived multiscale features as sensitive functional biomarkers for clinical evaluation. In this prospective case–control study, SERF-MEG recordings were acquired during a pattern-reversal visual stimulation paradigm. Time-domain evoked components (M100/M135), global electrophysiological indices, energy-based metrics, and alpha- and beta-band phase-based functional connectivity were extracted. Network topology was quantified using graph-theoretical measures, including global and local efficiency, clustering coefficient, and assortativity. Group-level differences between patients and healthy controls were statistically analyzed. Patients showed significantly reduced M100/M135 amplitudes, prolonged M100 latency, and a lower early-component energy ratio. Functional connectivity was significantly decreased in the alpha and beta bands, accompanied by reduced global and local efficiency, mean strength, and clustering coefficient. Seed-based analyses revealed reduced connectivity predominantly in occipito-parietal and occipito-temporal pathways. SERF-MEG provides sensitive identification of cortical- and network-level functional impairments following optic nerve damage. MEG has significant clinical potential for disease diagnosis and therapy monitoring, providing a novel objective assessment tool for neuro-ophthalmological disorders. Full article

Background/Objectives: A current debate addresses where syntactic Merge primarily resides: the left-hemisphere posterior inferior frontal gyrus (IFG) or the temporo-parietal cortex. For proponents of the former, the temporo-parietal cortex supports more effortful processing; for the latter, the IFG supports integration and conflict resolution. We examine aperiodic activity in processing wh-filler-gap dependencies in French for evidence from network dynamics addressing engagement in syntax across L1 and L2. Methods: We extracted aperiodic activity 1/f components (considering offsets as a reflection of neuronal spiking and exponents as a reflection of excitatory–inhibitory balance) out of power spectrum density at 0.5–40 Hz across occipital and bilateral frontal and temporo-parietal regions of interest (ROIs) in reading. Results: Greater exponents arose in temporo-parietal than frontal ROIs in L1 and L2, with strong spiking and regulation suggested by greater offsets and exponents in the occipital ROI in L2—unlike L1—and with potential modulation by L1–L2 representation overlaps. These patterns suggest distributed cell assemblies for L1 and L2 processing. Increased regulation in temporo-parietal ROIs across L1 and L2 cell assemblies might suggest a structural function across temporo-parietal cortices in syntactic processing. Conclusions: Aperiodic activity reflecting connectivity in L1 and L2 processing supports distinct L1 and L2 cell assemblies, with L2 patterns suggesting potential overlap between L1 and L2 circuit modules. Greater exponents in bilateral temporo-parietal ROIs across L1 and L2 indicate increased regulation, supporting the engagement of lateralized temporo-parietal cortices in computations. These effects are discussed by considering advances in syntactic theory and the biology of language readiness. Full article

This study introduces a new approach to image enhancement by integrating ideas from geometric function theory with modern computer vision techniques. A specific subclass $\mathcal{B}(\hslash )$ of bi-univalent functions is constructed, and its associated Hankel determinants are employed to design convolution-based enhancement filters. These determinants are incorporated as adaptive weights within the filtering process to improve image quality. The effectiveness of the proposed framework is assessed using widely accepted performance measures, including PSNR, SSIM, MSE, standard deviation, and Pearson correlation coefficient. Experimental results on various medical imaging datasets demonstrate clear improvements compared to existing methods. The proposed method is evaluated on different medical images obtained from publicly available Kaggle and Radiopaedia datasets. Quantitative comparison of the proposed method against two histogram-based enhancement methods, QDHE and CLAHE, demonstrates substantial improvements across all quality metrics, achieving superior image enhancement with better preservation of fine structural details. An ablation study confirms that Hankel weights contribute approximately 4.5 dB and directional fusion contributes 2.8 dB to the average PSNR. The findings demonstrate a quantifiable connection between the theory of Hankel determinants and practical image processing applications. Full article

We construct solutions of a time-harmonic Maxwell-type system within the framework of the algebra of complex quaternions. Using quaternionic analysis, we establish a connection between this system and certain first-order differential operators whose kernels consist of monogenic functions. Building on known representations of harmonic and monogenic functions, we develop a constructive procedure based on transmutation operators for generating explicit solutions of the equations $(D\pm \lambda )u=0$, and consequently of the corresponding Maxwell system. This approach provides a systematic method for reconstructing electromagnetic fields from harmonic and monogenic data, yielding an explicit link between quaternionic operator theory, transmutation methods, and the classical formulation of Maxwell equations. Full article

Zeolites, both natural (e.g., clinoptilolite) and synthetic (e.g., FAU, ZSM-5), provide robust, tunable platforms for the removal of air pollutants and process-stream contaminants via adsorption and catalysis. This author-led article integrates experimental and theoretical insights on the adsorption of odorous compounds and ammonia (NH₃) and the catalytic abatement of nitrogen oxides (NOx) and nitrous oxide (N₂O), highlighting how topology, acidity, and metal speciation jointly control performance. Representative theoretical results show that adsorption on Brønsted acid sites is significantly more favorable (≈−1.1 eV for NH₃ and −0.37 eV for acetaldehyde) than on Na⁺ sites (≈0.02 eV and 1.22 eV, respectively), demonstrating the critical role of acid site distribution in adsorption selectivity. We dissect structure–function relationships encompassing pore size and connectivity, Si/Al ratio, Brønsted/Lewis site distribution, hydrophilicity/hydrophobicity, and the role of water, with emphasis on hierarchical porosity to alleviate transport limitations. Metal exchange and surface functionalization are discussed as levers to tailor adsorption strength and redox activity, supported by density functional theory (DFT) analyses and reaction pathways. We propose practical design descriptors (acid strength metrics, metal nuclearity, and confinement factors) that enable faster iteration of zeolite architecture for targeted separations and reactions. Sustainability considerations include the use of abundant natural zeolites, low-energy regeneration, stability under humid, mixed-stream conditions that minimize pressure drop and waste. The article closes with a forward look at data-guided optimization to accelerate “engineering zeolites” for durable, selective, and energy-efficient clean-air and process-intensification applications. Full article

Anthropocene pressures underscore that human well-being and societal resilience depend on both biodiversity and geodiversity, the latter providing the abiotic foundation of Earth’s life-support systems. Despite increasing emphasis on systems thinking, participation, and action, Environmental Education and Education for Sustainable Development often underrepresent this abiotic dimension and leave ethical commitments insufficiently articulated. Addressing these gaps, this concept paper develops a convergence framework that integrates geoethics, geoeducation, and geoenvironmental education within the broader domains of EE and ESD. Drawing on interdisciplinary scholarship, geoethics is positioned as a normative lens that clarifies principles for responsible human–Earth relations, including responsibility, justice, respect for Earth processes, transparency in science communication, prudent resource use, and risk-aware decision-making. Geoeducation is conceptualized as the pedagogical vehicle through which these values are translated into competencies such as geoliteracy, systems thinking, critical reflection, ethical deliberation, and evidence-informed action, while geoenvironmental education provides the integrative content domain linking biotic, abiotic, and cultural dimensions. Place-based learning functions as the primary implementation pathway, with protected landscapes and UNESCO Global Geoparks serving as exemplary “living laboratories” where geoconservation, education, and sustainable development are co-produced with local communities. The paper advances three interrelated contributions: (a) a conceptual convergence framework, (b) an operational definition of geoethical awareness, and (c) a programmatic model linking geoethical values to competencies, pedagogies, indicators, and place-based implementation strategies. Operationalized through a Theory of Change and a translation matrix connecting principles to educational outcomes, the framework provides a foundation for future empirical research, curriculum development, teacher education, and the cultivation of geo-citizenship, stewardship, and more resilient human–Earth relationships. Full article

Urban fire prevention is shifting from reactive response to proactive risk governance, yet current approaches often overlook risk-type heterogeneity, spatial dependencies, and underlying behavioral mechanisms, especially equitable risk distribution among vulnerable groups. To address this, this study integrates the Pressure–State–Response (PSR) model with environmental criminology theories (Routine Activity Theory (RAT) and Crime Pattern Theory (CPT)) to couple macro social causal chains with micro behavioral–spatial mechanisms. Using data from the digital urban management system of Shenzhen’s Guangming District in 2019, four fire risk event types are examined: electric bike charging violations (EB), unauthorized power wiring (PW), water heater misuse (WH), and aging gas pipelines (GP). Spatial error models explain 82–89% of the variance across fire risk event types, and spatial 5-fold cross-validation shows minimal performance decline (ΔR² = 0.03–0.08), confirming robust prediction without overfitting. Key findings include: (1) elderly proportion is significantly positively associated with WH and PW (coefficients = 2.64 and 3.06, p < 0.01); (2) restaurant density has a consistently positive association with all four risk types (coefficients = 0.24–0.60, p < 0.01); (3) functional diversity and connectivity exhibit dual patterns, showing negative associations with more visible, easily detectable violations (PW, GP) but positive relationships with relatively concealed behaviors (EB); (4) reported safety deficiencies display strong positive associations with all fire risk event types and can therefore serve as an effective early-warning indicator for broader fire risk. These results support risk-specific, equity-oriented prevention strategies that prioritize vulnerable groups and high-risk environments. The validated PSR–RAT/CPT framework provides a novel theoretical basis for targeted fire risk governance and advances safe, resilient, inclusive cities aligned with Sustainable Development Goal 11. Full article

Rapid urbanization has intensified wetland fragmentation and ecological connectivity degradation, threatening the structural stability and functional sustainability of urban wetland ecosystems. Constructing resilient wetland ecological networks is therefore essential for maintaining regional ecological security and supporting sustainable urban development. Taking Wuhan as a case study, multi-temporal land-use data from 2004, 2014, and 2024, together with land-use transition matrices, were used to analyze urban expansion and wetland landscape transformation. Morphological Spatial Pattern Analysis (MSPA), the Minimum Cumulative Resistance (MCR) model, and circuit theory were integrated to identify ecological sources, construct ecological corridors, and evaluate the structural connectivity of the wetland ecological network. Ecological source importance was quantified using the Probability of Connectivity (PC) and dPC indices. In addition, robustness analysis based on the sequential removal of high-dPC ecological source patches was conducted to assess network stability under disturbance scenarios. The results identified 20 core ecological source areas and 45 ecological corridors, forming a relatively interconnected wetland ecological network centered around major lake clusters and key ecological hubs. High-current corridors and pinch points were mainly distributed in ecologically sensitive transition zones and urban expansion boundaries. Robustness analysis showed that sequential removal of high-dPC ecological hubs resulted in continuous declines in EC(PC) and corridor number, while corridor length increased substantially. Although overall connectivity was maintained through alternative ecological pathways, ecological movement efficiency decreased significantly under disturbance scenarios, indicating increasing dispersal costs and reduced structural stability. These findings suggest that the wetland ecological network possesses moderate structural connectivity through pathway redundancy but remains highly dependent on several dominant ecological hubs. This study extends traditional static connectivity assessment by incorporating robustness and disturbance response analysis into wetland ecological network evaluation. The proposed framework provides scientific support for resilient wetland conservation, ecological restoration, and sustainable spatial planning in rapidly urbanizing metropolitan regions. Full article

With the large-scale integration of wind farms, the spatial distribution characteristics of system dynamic frequency response become increasingly prominent. Existing wind farm planning methods considering frequency constraints mostly rely on predefined disturbance scenarios or system-level average frequency indicators, failing to account for the spatial randomness of disturbance locations. This leads to potential safety risks of local bus frequency limit violations when the systems planned accordingly are subjected to uncertain disturbances in actual operation. To address this issue, this paper proposes an optimal wind farm planning method based on frequency response upper bound constraints. The proposed method utilizes the algebraic connectivity index to characterize the theoretical upper bound of system frequency response under uncertain disturbances, which is then incorporated into the planning model as a constraint, thereby avoiding the risk of frequency limit violations in weak areas of the network. First, based on the closed-loop transfer function model and infinity norm theory, the theoretical upper bound of frequency response under uncertain disturbances is derived, and an upper bound evaluation index explicitly correlated with algebraic connectivity is constructed to identify the worst-case frequency response under uncertain disturbances. Second, the upper bound evaluation index is transformed into constraints for the wind farm siting and sizing model and an optimal planning method based on the frequency upper bound constraint is proposed. Simulation results on the IEEE 39-bus system show that, when a 1.2 p.u. active-power disturbance is applied at each bus individually, the proposed planning method reduces the average maximum frequency deviation by 36.78% relative to the unoptimized siting-and-sizing scheme (arithmetic mean across 39 bus-wise scenarios); for eight preset topology change scenarios, it yields a further 7.03% average reduction in maximum frequency deviation relative to the unoptimized scheme under each scenario topology. Full article

Detecting R-peak location is very important in electrocardiogram (ECG) analysis. Most existing algorithms focus on separating extreme data points to find R-peaks without ECG wave morphology consideration. As a result, we propose a new algorithm using graph theory to integrate non-linear connections between states. Specifically, we design a weighted directed graph to represent the structure of an ECG wave where each vertex corresponds to a time index and a state of an ECG signal. Therefore, traversing each edge corresponds to labeling a contiguous segment of the signal as a specific ECG state. Each edge also contains a weight corresponding to a cost function and bias. Dynamic programming is used to determine the shortest path corresponding to the optimal labeling by iterating through the topological ordering of the graph. Three logical flags based on the constraints of the ECG signal’s slope, difference, and shape are also introduced and the slope thresholding value for an R-peak is made adaptive to combat varying morphologies. Four datasets were utilized, with the proposed method showing great potential, achieving an accuracy of 99.07% for the MIT-BIH dataset, 99.46% for the QT dataset, 98.05% for the INCART dataset, and 99.23% for the ST CHANGE dataset. Full article