Search Results (1,328)

Digital rock technology is essential for characterizing the petrophysical properties of tight reservoirs. However, conventional construction methods often yield models with insufficient pore connectivity due to low porosity and complex nanopore structures. To address this limitation, we propose a novel connectivity algorithm for isolated pore systems. First, a digital rock model is constructed using a random particle packing algorithm that integrates high-resolution SEM parameters, including kaolinite particle morphologies and randomly distributed microfractures. Subsequently, the connectivity algorithm sequentially links isolated pore clusters to the largest continuous pore system, forming an interconnected channel. Pore network extraction reveals that the algorithm produces significantly denser and more continuous structures, with pore–throat size distributions aligning well with experimental observations. Single-phase flow simulations demonstrate that the enhanced model yields porosity and permeability values consistent with laboratory measurements, whereas unenhanced models deviate substantially. To further advance microscale flow characterization, we derive explicit fitting formulas for the dimensionless conductivity of canonical pore cross-sections (equilateral triangle, square, and circle) considering water film boundary layer (WFBL) effects. These formulations are based on a comprehensive parametric study using the ab initio finite element method, followed by regression analysis to yield closed-form expressions. Two-phase flow simulations reveal that the WFBL increases residual saturations, reduces relative permeabilities, and decreases waterflooding displacement efficiency, with effects being more pronounced during secondary imbibition. This integrated approach provides a robust framework for constructing representative digital rock models of tight reservoirs and offers essential theoretical support for accurately modeling nanoscale flow behaviors in complex subsurface systems. Full article

Resistive random-access memory (RRAM) has emerged as one of the most promising device platforms for neuromorphic, in-memory computing because its two-terminal metal–insulator–metal (MIM) structure can reproduce the weight-update behavior of biological synapses while remaining compatible with mainstream CMOS processing. This review summarizes the current state of RRAM-based neuromorphic technology from four complementary perspectives: device physics, materials, fabrication processes, and packaging. We first describe the operating principles of filamentary and interface-type RRAM, including the forming/set/reset switching sequence, and the two dominant analytical frameworks used to describe the reset transition—the ion-migration model and the thermally driven filament-dissolution model. We then review the switching-layer and electrode materials that have been most widely investigated such as HfO_x, TiO_x, TaO_x, ZnO, ZrO₂, and Cu/Ag-based conductive-bridge systems, together with representative bilayer and doped architectures reported for synaptic devices. The biological functions that RRAM can emulate are discussed alongside the non-ideal characteristics that currently limit on-chip training accuracy, with emphasis on separating device-to-device from cycle-to-cycle variability and on the workload-dependent nature of endurance and retention requirements. We further summarize the process technologies used to integrate RRAM into large-scale, CMOS-compatible arrays, including atomic layer deposition, interfacial oxygen-reservoir engineering, low-thermal-budget back-end-of-line integration, and three-dimensional vertical RRAM patterning, and discuss the advanced packaging strategies such as 2.5D/3D heterogeneous integration, chiplet architectures, thermal-interface materials, and nanostructured underfills required to manage the power density and interconnect demands of large synaptic arrays, distinguishing solutions that have been demonstrated specifically for RRAM neuromorphic arrays from those that remain general advanced-packaging concepts. Finally, RRAM is benchmarked against competing emerging non-volatile memories, and the key research directions such as three-terminal memtransistor architectures, three-dimensional integration with high-performance selectors, and hardware–algorithm co-design that will determine whether RRAM-based neuromorphic hardware can move from laboratory demonstrations to on-device AI, autonomous systems, and large-scale artificial-neural-network accelerators are outlined. Relative to prior reviews that focus primarily on RRAM device physics or on switching-layer materials in isolation, the distinctive contribution of this review is an explicit, cross-layer synthesis that connects device-level non-idealities to their consequences for wafer-scale process integration and for advanced 2.5D/3D packaging—a combination that, to our knowledge, has not been jointly treated in the recent review literature on RRAM-based neuromorphic hardware. Full article

Research on teacher digital competence has expanded sharply over the past decade. However, the field’s development, thematic structure, and underlying terminological characteristics have remained under-examined. The rapid integration of artificial intelligence has compounded this challenge, introducing new competence-related constructs and reshaping the field’s conceptual landscape. In the context of Sustainable Development Goal (SDG) targets 4.4 (developing digital skills) and 4.c (ensuring a supply of qualified teachers), this raises the question of whether the knowledge base is developing coherently. To address this question, we analyse a corpus of 4097 Scopus-indexed publications retrieved through a broad search on teacher digital competence, published between 2015 and 2025, using longitudinal bibliometric analysis and science mapping. The analysis reveals marked terminological variability: a high Pielou’s evenness index (J′ = 0.86) indicates that occurrences are distributed relatively evenly across 8567 normalised terms, suggesting the absence of a strongly dominant terminological core at the corpus level, while singleton terms account for a large share of the vocabulary (76%), pointing to substantial fragmentation. Against this fragmented backdrop, an AI-oriented strand accounts for 10.4% of the corpus and rises to 26.1% of annual output by 2025; rather than displacing established competence-related concepts, AI-related concepts form an emerging technological layer within teacher digital competence research. These thematic patterns are accompanied by uneven publication activity and international collaboration. Taken together, these findings indicate that the conceptual boundaries of teacher digital competence research are shaped by substantial terminological variability and ongoing thematic expansion. They further highlight the importance of transparent search strategies and greater terminological clarity and consistency for improving the comparability, reproducibility, and cumulative development of research in this field. Full article

Ni–Mo alloy claddings were fabricated on low-carbon steel substrates using powder metallurgy combined with hot isostatic pressing (PM-HIP). The interfacial microstructure, elemental interdiffusion, phase composition and microhardness distribution of the bimetallic composite were investigated systematically. The results show that sound metallurgical bonding without pores, cracks and element dilution is achieved under the HIP process of 1100 °C, 120 MPa and 4 h holding time. Interdiffusion of Fe, Ni and Mo atoms forms a 20–50 μm thick interfacial transition layer, and Mo exhibits a relatively low diffusion capacity due to its large atomic radius. Two intermetallic phases, Ni₄Mo and NiMo, are formed in the cladding layer because of the inhomogeneous distribution of Mo. A prominent microhardness gradient is observed throughout the composite, and the interfacial layer presents the highest hardness of 905 HV resulting from multiple strengthening mechanisms. As an effective alternative to traditional welding and cladding technologies, the PM-HIP process exhibits great potential for manufacturing complex bimetallic components with prospective service prospects in severe corrosive environments. Full article

This article presents a practice-oriented methodological proposal for designing inclusive multimodal learning content with Generative AI (GAI) in migrant adult literacy. It does not report an experimental intervention or a statistical evaluation of learning outcomes. Its contribution lies in formalizing a context-sensitive design pathway for early preA1–A2 literacy and language-learning provision in Italian CPIA settings, where learner profiles are highly heterogeneous, attendance may be discontinuous, and written language is both a learning goal and a barrier to participation. Unlike generic AI-supported instructional design frameworks, the proposed approach starts from recurrent communicative needs in adult migrant education and translates them into short, modular and reusable learning artifacts that coordinate textual, visual, audio-oral and interactive layers. The framework distinguishes multimodal design, understood as the pedagogical coordination of different semiotic modes, from the mere use of multiple media. It also integrates accessibility as a set of concrete design criteria, including linguistic readability, visual clarity, audio quality, layout, font size, contrast, cognitive load and usability in print or mobile formats. The article outlines a sequence of design operations: mapping learner profiles, selecting situated communicative scenarios, generating and revising textual material, developing visual and audio scaffolds, structuring guided interaction, and applying pedagogical, cultural and ethical review. An illustrative micro-unit on asking for information at a municipal office shows how this pathway can support dialog, visual glossary, audio practice, role-play and formative assessment. The proposal is intended for CPIA educators, adult literacy professionals, instructional designers and researchers in multimedia learning and educational technology. Its educational implication is that GAI can support inclusive material design only when its outputs are treated as provisional resources to be selected, adapted and validated through human pedagogical judgment. Full article

High-bandwidth memory (HBM) faces critical power integrity challenges in high-stack configurations due to elongated power delivery paths and increased parasitic inductance. This paper proposes a dual-interposer HBM architecture with an interposer–HBM stack–interposer configuration, integrating an additional top interposer embedded with chip capacitors. This topology redesigns the HBM’s power distribution network, reducing PDN impedance, and this technology enables bidirectional vertical power supply to DRAM chips during moments when they require current. The PDN impedance is systematically compared with a conventional trench-capacitance-enhanced structure (Structure A) and a deep-trench-capacitance-enhanced structure (Structure B). Results show that at 0.1–11.2 GHz, the proposed structure reduces peak PDN impedance by 66.41% and 65.7% versus Structures A and B, respectively, and decreases the loop inductance of the top-layer DRAM chip by 66.71%. The top interposer’s redistribution layer forms a parallel-plate capacitor complementing the embedded chip capacitors, achieving wideband impedance suppression. Without modifying existing protocols, this architecture provides a system-level PDN optimization strategy for high-stack HBM, offering quantitative insights for capacitor selection and layout design. Full article

As China’s dominant urban housing form, gated residential communities deploy layered spatial access controls governing who may enter and move through neighbourhood space. While neighbourhood social sustainability has attracted substantial scholarly attention, how micro-spatial governance arrangements affect the inclusiveness of residential built environments toward essential service workers remains underexplored. Drawing on Lefebvre’s theory of the production of space, this study uses food delivery riders—who navigate gated community access controls dozens of times daily—as an analytical lens to evaluate how neighbourhood spatial governance shapes social inclusiveness. Vignette-based survey data from 445 riders across 157 cities in 27 Chinese provinces were analysed using structural equation modeling. Results show that cumulative anxiety from procedural delays, detours, and elevator waiting is the dominant pathway through which spatial governance undermines riders’ perceived spatial inclusion—operationalised through occupational dignity indicators—with elevator-based spatial stratification identified as a concrete, low-cost intervention target within the spatial-channeling mechanism. Technology-mediated access partially mitigates face-to-face exclusion but leaves underlying spatial inequalities intact. Demographic invariance across all tested variables confirms that diminished inclusion arises from the governance regime itself. The findings position neighbourhood spatial governance as a measurable dimension of urban social sustainability—one concretely testable through the experience of essential service workers—and identify low-cost built-environment interventions for inclusive residential design. While the study focuses on riders as a single user group, the analytical framework is transferable to evaluating how residential built environments accommodate diverse non-resident populations. Full article

China–Iraq international energy cooperation on natural gas constitutes a critical component of energy diplomacy under the Belt and Road Initiative. This study develops a multidimensional analytical framework encompassing geopolitical, economic–market, legal–policy, resource–technology, social–environmental, and bilateral–institutional dimensions. Subsequently, an integrated fuzzy DEMATEL-ISM model is employed to investigate the hierarchical structure and transmission pathways of influence among these factors. The findings reveal that the multiple factors can be classified into four clusters (driving, linkage, independent, and dependent), each exhibiting distinct roles in system evolution. Meanwhile, the model identifies a six-tier hierarchical structure, with directed pathways transmitting from deep-rooted factors through intermediate nodes to surface-level outcomes. Surface-level factors occupy the upper tier and directly shape cooperative performance, while intermediate-level factors act as transmission conduits that relay and transform deeper influences. Deep-level factors, including great-power rivalry, resource endowment, and market demand, form the system’s foundational layer. They remain immune to influence from upper tiers and thus require strategic governance to fundamentally ensure enduring cooperation sustainability. Consequently, policy priorities should center on deep-level drivers, complemented by targeted adjustments to intermediate and surface factors. This study offers a novel multi-level structural analytical lens and provides actionable policy recommendations to enhance cooperative resilience under the Belt and Road framework. Full article

In the mining process of shallow-buried and close-distance coal seam groups in western China, the interconnected collapse fractures between the overlying goaf and the surface form large-area composite goafs, which aggravate surface air leakage and elevate oxygen levels within the goaf. This, in turn, leads to hazardous conditions such as CO over-limits and O₂ deficiency at the working face’s return air corner, which seriously threatens the respiratory health of underground operators and the safe production of mines. Taking the 104 working face of a coal mine in Shenfu-Dongsheng Mining Area as the engineering background, this paper comprehensively adopts SF₆ tracer gas test, fuzzy cluster analysis, and CFD numerical simulation methods to systematically study the distribution characteristics of three-dimensional air leakage channels in composite goafs and their influence mechanism on gas migration in goafs, and proposes a dynamic pressure equalization ventilation (PEV) regulation technology system. The research results show that a multi-dimensional three-dimensional air leakage channel of “surface-interlayer-own layer-roadway” exists in the research area, in which the surface fracture air leakage velocity is about 0.068 m/s, and the interlayer and internal goaf air leakage velocity is about 0.384 m/s. The atmospheric pressure difference between the working face and the surface is the main controlling factor inducing the O₂ deficiency disaster of the working face. Every 100 Pa change in atmospheric pressure difference causes an O₂ concentration fluctuation of about 0.30% at the return air corner, and the critical pressure difference for activating PEV is determined to be 300 Pa. Setting the PEV regulation point at the return air outlet of the working face and adopting the combined dynamic regulation system of fans and air windows can realize accurate pressure balance between the working face and the overlying composite goaf. Full article

Copper and its alloys are indispensable for electronics, communications, new energy systems, and aerospace engineering due to their exceptional electrical conductivity and mechanical properties. However, the thin cuprous oxide (Cu₂O) layer that naturally forms on copper and its alloys is prone to failure under elevated temperatures and high humidity, particularly in chloride-rich environments, leading to accelerated localized corrosion. While conventional chromate-based passivation has long been the industrial standard for preventing corrosion, its use has been increasingly restricted by global regulations (such as RoHS and REACH) due to its severe toxicity and health risks. To address the conflict between environmental compliance and protective performance, this review systematically evaluates recent advances in environmentally friendly, chromium-free anti-corrosion coatings in the present review. These alternative coatings are critically analyzed and categorized into four mechanistic groups: (i) inorganic conversion coatings (including molybdate, tungstate, rare earth, and phosphate systems); (ii) organic films formed via chemical or physical adsorption (such as organic inhibitors, thiol-based monolayers, and organosilane self-assembled films); (iii) conversion coatings engineered through covalent bonding, coordination chemistry, and microstructural tailoring; and (iv) multifunctional coatings that integrate self-healing capability with high electrical conductivity. Beyond providing a technical summary, this review explored how the swift progression of electronic information technology, new energy infrastructure, and robotics has imposed more exacting, multifunctional demands on copper components. This review provides a strategic roadmap for future research and prioritizes the creation of protection strategies that operate robustly in multi-physics coupling environments—integrating high conductivity, autonomous self-healing, and long-term chemical stability to ensure the reliability of next-generation infrastructure. Full article

This article presents the results of a numerical study of the construction and technical characteristics of multilayer concrete wall blocks. The study focuses on the development of wall building elements that integrate structural strength, thermal insulation, and protective–decorative functions by creating a stable multilayer concrete structure consisting of concretes with different compositions, variatropic architecture, and discretely graded density. The development of durable multilayer concrete technologies is hindered by several major challenges, including the absence of a scientifically validated methodology for designing multilayer concrete structures, which complicates the determination of the optimal geometric parameters of the elements, as well as the difficulty of forming individual layers with the required thickness. The objective of the study was to analyze the thermal and strength properties of numerical models of a multilayer wall block consisting of two to five concrete layers of variable densities. ELCUT-7 (thermal properties) and SolidWorks Simulation 2022 SP4.0 (strength properties) software packages were used to create and study the numerical models. The initial data for creating the numerical models were the results of experimental studies of concrete of various compositions and structures with a density of 500–2200 kg/m³. Several variants of block models with two to five layers were studied. The variants differed in the thickness and composition of the concrete layers, as well as the position of the layers in the block structure. A comparative analysis of the calculated values of thermal transfer resistance for blocks with a different number of layers and variable concrete density was performed. The appropriateness of concrete blocks containing three or more layers was proven. Increasing the number of layers in blocks creates a variatropic structure for multilayer concrete, eliminating sharp variations in the density of adjacent layers while maintaining the thermal efficiency of the wall enclosure. Increasing the number of layers in concrete blocks expands the possibilities for combining layer compositions and thicknesses. In multilayer concrete blocks, it is possible to reduce the thickness of the highly porous layer by thickening the less porous adjacent layers without compromising thermal performance. Blocks with four and five layers of concrete of variable densities are comparable in strength and structural efficiency to blocks with fewer layers. For the same thermal resistance, the thickness of the five-layer block is 38–48% less than that of a conventional single-layer concrete element. Furthermore, the structural efficiency coefficient of the four- and five-layer blocks is 1.08–1.12 times higher than that of a three-layer block with equivalent load-bearing capacity. The results of these numerical studies serve as the basis for designing manufacturing processes for wall blocks with variatropic structures. Full article

Students in higher education often face challenges related to motivation, self-regulation, and engagement. This article presents TIRIA, a user-centered learning analytics dashboard designed for Moodle and adaptable to other Learning Management Systems (LMSs), and reports a formative evaluation of its high-fidelity prototype. The design followed a Design Thinking methodology informed by a targeted literature review, interviews with 10 instructors and 9 students, and iterative prototyping. TIRIA integrates visual analytics, personalized feedback, and a gamification layer (points, badges, goal-setting, and a virtual assistant), aligned with Self-Regulated Learning (SRL) theory and interpreted through Self-Determination Theory (SDT). Because the evaluation used a Figma prototype populated with mock data rather than a deployed integration, the study reports perceptions rather than learning outcomes. Six undergraduate students completed think-aloud sessions, a semi-structured interview, and a survey combining the System Usability Scale (SUS), a Technology Acceptance Model (TAM) measure, and two five-item measures adapted from learning analytics quality indicators and from gamification research. Participants rated usability highly (SUS = 93.75, PEOU = 4.75) and consistently valued organizational features, while responses to the gamification layer were markedly polarized (individual means ranging from 1.2 to 5.0). The article contributes a documented design case mapping features to SRL phases and SDT constructs, formative evidence supporting an opt-in approach to gamification, and implementation considerations covering privacy and Moodle integration. Findings are exploratory and require confirmation through deployment in an authentic learning environment. Full article

To address the challenge of surrounding rock control in deep gob-side entry driving, the return airway of the 20203 working face of the Dahaize Coal Mine was taken as the engineering background. The stress, deformation and plastic zone evolution characteristics of the surrounding rock of the gob-side entry were studied through theoretical analysis, numerical simulation and field tests, and the surrounding rock control mechanism and the double-layer flexible thick anchor control technology were proposed. The results show that under the influence of the adjacent gob, the peak compressive stress of the gob-side entry is transferred to the solid coal side, and tensile stress areas are generated on the roof; shear failure is the main failure pattern of the surrounding rock in the gob-side entry, which is characterized by significantly asymmetric deformation. Based on the displacement failure characteristics of the surrounding rock zones, a double-layer flexible thick anchorage structure was constructed. The anchorage depth of the first basic support exceeds the critical thickness of the shallow fractured surrounding rock zone, forming a thick load-bearing layer for the roadway surrounding rock; the anchorage depth of the secondary reinforced support extends into the stable rock mass, enhancing the bearing capacity of the anchored body and the roadway surrounding rock. The results of numerical simulation show that after adopting a double-layer flexible thick anchor support, the average deformation of the roof decreases by 48.81%, and the range of the tensile stress zone and plastic zone is significantly reduced. In engineering applications, the average deformation of the roadway roof was 42.58 mm, the two-end convergence was 0–2 mm, the roof separation value was controlled within 0–30 mm, and the rock strata within 0–5.0 m remained intact. This technology effectively suppresses the large deformation of the surrounding rock in deep gob-side entry, providing an innovative strategy for roadway stability control under comparable geological and mining conditions. Full article

Extracting lithium from salt-lake brines boasts distinct advantages including low production cost, low energy consumption and low environmental risks, and will serve as a primary supply source of lithium salts in the future. This trend raises higher demands for the efficiency and cost-effectiveness of lithium extraction technologies. Nanofiltration (NF) membranes, renowned for their superior discrimination between monovalent and divalent ions, have been extensively utilized to obtain Li⁺ from Mg²⁺-rich saline brines. In this study, positively charged NF membranes aimed at Li⁺/Mg²⁺ fractionation were fabricated via surfactant-interlayer-assisted interfacial polymerization (SIAIP). Catechol (CA) and polyethyleneimine (PEI) were utilized to construct the CA/PEI interlayer, and oil-phase dodecyl phosphate (DDP) was used as an additive for interfacial polymerization (IP). The strongly bonded CA/PEI nanoaggregates improved interlayer stability and preserved the positive charge of the double-layer membrane. DDP adsorbed piperazine (PIP) at the two-phase interface through electrostatic interactions, accelerating PIP diffusion and forming a thick polyamide (PA) layer with uniform pores. The combination of CA/PEI interlayer and DDP synergistically enhanced size-sieving and Donnan effects. With MgCl₂ and LiCl rejections of 97.9% and 36.2% respectively, the optimized membrane shows superior selectivity for Li⁺ over Mg²⁺. Moreover, the membrane exhibited weak electrostatic screening and concentration polarization, showing excellent operational stability under varied Mg²⁺-Li⁺ ratios and feed concentrations. Full article

Among the vast array of technologies available for surface modification of materials, sputtering emerges as one of the most versatile methods through coating deposition. Included in the family of physical vapor deposition (PVD) techniques, sputtering allows the production of coatings with a great variety of characteristics, based on a bottom-up approach that forms coatings from individual species (atoms or ions). This versatility is achieved by controlling: (i) the layer architecture, from monolithic to multilayers, (ii) the structures, from amorphous to nanocrystalline or nanocomposite, until highly crystallized, including epitaxial; (iii) the morphologies, from very porous through columnar or zig-zag to very dense and featureless; (iv) the chemical composition, allowing the deposition of metallic, polymeric, ceramic or composite materials types. In this paper, after a brief introduction of sputtering as a deposition technology, we will review the application of sputtering for depositing protective coatings to which an extra functionality is provided: (a) aesthetic color; (b) high-temperature lubrication; and (c) temperature sensing ability. Full article