Search Results (262)

To address the issues of insufficient pre-dispersion in the classification zone and inadequate powder-processing capacity in traditional turbine-type air classifiers, this paper proposes a bottom-fed vertical triple-cage classifier. Numerical simulations were performed using the finite element analysis software ANSYS FLUENT to compare and analyze the influence of the classifier chamber structure on flow patterns and classification performance. The results reveal that when the top diameter of the classification chamber is relatively large, with a top-diameter-to-rotor-diameter ratio of 1.45–1.50, the energy consumption of the rotating cage increases, and the scale of vortices within the classification zone increases significantly. Conversely, when this ratio falls within the range 1.30–1.35, wear on the chamber walls becomes markedly more severe. Among the tested configurations, the T-C-type chamber, which features a ratio of 1.40, proved to be the optimal structure, delivering a separation sharpness of 0.71 and a cut size (Dc) of 22.4 µm. This study provides a theoretical basis for the structural optimization design of such classifiers. Full article

Gas Electron Multiplier (GEM) detectors have become an indispensable component of modern tracking systems. The heart of a GEM detector is a thin polyimide foil (∼50 µm) clad with copper (∼5 µm) on both sides and containing an array of regularly spaced holes (typically diameter of ∼70 µm and pitch of ∼140 µm) fabricated using photolithographic techniques. The presence of the dielectric substrate (polyimide) within the amplification region introduces a time dependent response when the detector is exposed to external irradiation, a phenomenon commonly referred to as the charging-up effect. This effect arises from the accumulation of charge on the insulating polyimide surfaces, leading to a gradual modification of the local electric field configuration inside the GEM holes and, consequently, a variation in the detector gain over time. The charging-up behaviour has been systematically investigated for triple GEM chamber prototypes using an Fe-55 radioactive source (5.9 keV X-rays) with an activity of ∼20 mCi. The characteristic charging-up time constant has been extracted, and its dependence on detector gain and irradiation rate has been examined. In addition, the uniformity of detector performance in terms of count rate, gain, and energy resolution has been studied both before and after the charging-up process. In this review article, the experimental setup, data acquisition methodology, and analysis procedures developed and carried out by our group are summarised. The key findings reported by other groups, relevant Monte Carlo simulation efforts, and future outlook for the charging-up investigation on GEM based detectors are also discussed in this article. The investigations and their outcomes reviewed here provide valuable insight into the charging-up dynamics of GEM detectors and their dependence on operational parameters. Full article

Postharvest seed cleaning is critical for ensuring high-quality rice seeds suitable for storage and planting. Traditional cleaning systems, which are often limited to one or two sieves, are insufficient for removing all impurities, resulting in reduced seed purity and potential germination issues. This study was designed to enhance the rice seed cleaning system by integrating a high-efficiency blower with a triple-sieving mechanism. The system utilized three sieves with progressively smaller mesh sizes to systematically separate contaminants such as dust, broken grains, husks, and other foreign particles. A controlled airflow from the blower distributes rice seeds uniformly across the sieves, optimizing separation while minimizing mechanical damage. Compared to existing conventional systems, the proposed design demonstrated significantly improved cleaning performance, resulting in higher seed purity levels and overall enhanced seed quality. The triple-sieve configuration, coupled with precise airflow control, led to more effective impurity removal and uniform seed handling. The improved seed-cleaning system offers several agronomic benefits, including reduced postharvest losses, increased seed germination rates, and improved crop establishment. By producing cleaner, higher-quality seeds, this system has the potential to support more efficient and productive rice cultivation. Full article

Existing accounts of platform-mediated complementor growth rest on two limiting assumptions: that platform enablement constitutes a homogeneous environmental input and that firm growth is a unitary outcome. This double simplification obscures how distinct platform provisions generate qualitatively different forms of firm transformation. This study asks which combinations of mechanistically distinct platform enablement types and internal strategic response capabilities activate which forms of leapfrog growth among complementor firms operating under dual institutional governance. We employ fuzzy-set Qualitative Comparative Analysis (fsQCA) on survey data from 374 complementor firms in China’s autonomous driving platform ecosystem. Five antecedent conditions are examined across two dimensions: platform enablement, comprising rule-based enablement (RE) and business platform enablement (BPE); and strategic response capabilities, comprising network linkage capability (NLC), organizational ambidexterity (OA), and policy responsiveness (PR). Three outcome variables capture three non-reducible leapfrog dimensions: technology-chain (TL), value-chain (VL), and institutional-chain (IL) transitions. A reverse-causality robustness check and a common-method-bias assessment corroborate the validity of findings. The analysis identifies equifinal configurational pathways with distinct dominant logics across the three chains. Technology-chain transitions are predominantly network-linkage-driven; value-chain transitions are policy-responsiveness-anchored; institutional-chain transitions exhibit genuine equifinality between network-linkage and policy-responsiveness pathways, both requiring dual-platform enablement as a universal structural precondition. No single enabling condition or capability suffices; leapfrog growth is irreducibly configurational and causally asymmetric. The study offers a dual-enablement, three-chain configurational framework for understanding platform-mediated firm growth under dual institutional governance. For complementor firms, findings support dimension-selective capability investment over uniform accumulation strategies. For platform orchestrators, differentiated governance design calibrated to specific complementor upgrading trajectories outperforms homogeneous resource provisioning. For policymakers, institutionalized consultative channels linking private platform governance with public regulatory processes are recommended to facilitate coordinated digital industrial transformation. Full article

Improving energy efficiency and reducing carbon emissions have become critical challenges in urea production, motivating increased interest in recovering mechanical energy within the process. This study develops a superstructure-based work exchange network with direct work exchangers to analyze mechanical energy recovery in urea synthesis. The work integration (WI) method is evaluated for single-, double-, and triple-stage configurations across different production capacities and compared with a conventional HPRT-based system. Results show that WI consistently outperforms HPRT in both energy recovery and CO₂ reduction. The single-stage configuration achieves the highest energy recovery, reaching 8448 MWh/year at 3710.83 t/day, an 18.8% improvement over HPRT. Wind power has the lowest carbon intensity, and emission reduction increases with production capacity. The largest absolute CO₂ reduction occurs in the single-stage case, while the greatest relative improvement (up to 41.1%) is observed in the three-stage configuration. Overall, WI significantly enhances energy efficiency and environmental performance in urea production. Full article

Four-point bending tests were conducted on precast ultra-high-performance concrete (UHPC) segmental beams reinforced with unbonded prestressing tendons. A nonlinear finite element model was established and rigorously validated against the experimental data to simulate their flexural behavior. The experimental results show that compared with monolithic beams, the segmental beams experience a slight reduction in flexural capacity of 9.22% and 12.44% for the double-joint and triple-joint configurations, respectively. Nevertheless, the segmental beams possess greater ductility reserves; specifically, their average peak displacements increased from 9.83 mm for the monolithic beams to 11.60 mm and 14.78 mm for the double-joint and triple-joint beams, respectively, demonstrating substantially improved ductility. Based on the validated finite element model, extensive parametric analyses were performed. The numerical results indicate that concrete strength and steel strand reinforcement ratio significantly enhance the load-carrying capacity. Furthermore, shifting the joint positions away from the loading points increases the beam’s bending capacity, though this enhancement aggressively flattens out beyond a critical distance threshold of 0.25 L (L is the effective span). Finally, segmental beams with shear-resistant keyed joints exhibit higher overall stiffness and ultimate load-carrying capacity compared to those with plain flat joints. Full article

Outdoor open spaces are essential for daily activities in ageing rural environments, yet the thermal effectiveness of vegetation under varying structural configurations remains unclear. Most existing Outdoor Thermal Comfort studies focus on dense urban canyons; the present study addresses this gap by examining a complexity threshold in vegetation cooling under high-SVF rural conditions and the radiation–ventilation trade-off that underlies it. An ENVI-met model was calibrated using field data from a typical village on the North China Plain and 17 vegetation scenarios were simulated. The findings reveal a non-linear relationship between vegetation complexity and cooling efficiency. A threshold of complexity was observed: the cooling performance declined with an increase in stratification from a double-layer (Scenario 12) to a triple-layer (Scenario 14) structure, with the change in mean radiant temperature (∆T_mrt) dropping from 23.16 °C to 21.10 °C. This is due to a radiation–ventilation trade-off, in which denser vegetation increases shading but reduces near-surface ventilation. Dense arrangements exhibit a heat trap effect, with the long-wave radiation flux changing from a cooling (−3.42 K/h) to a heating (+2.11 K/h) state. The results show a threshold effect in vegetation cooling and that thermal comfort is not necessarily enhanced by increased complexity. A shaded-canopy and permeable-understory structure is found to be optimal. The findings inform vegetation design in climate-adaptive rural settings. Full article

This study proposes a new method for rolling steel balls using spiral discs. The aim of the study was to investigate whether the proposed method could be used to produce balls with a diameter of 63 mm, as well as to determine the effect of tool geometry and the number of billets on process stability, force, and the energy parameters of the rolling process. Numerical simulations were performed using Forge^® NxT v.4.0. The billet for rolling was made of C60 steel and preheated to 1050 °C. The following cases of ball rolling were simulated: Ball rolling using flat discs with single, double, and triple spiral impressions made on their working surface, and ball rolling using tapered discs for two different configurations of the working system. The rolling process was examined in terms of ball shape, internal defect formation, temperature distribution, as well as force and energy parameters. The results showed that the rolling process conducted using tapered discs and by flat discs with single and double impressions produced correctly shaped balls without internal cracks. It was also found that discs with double impressions were more advantageous than the single-impression ones in terms of energy consumption, while the use of discs with triple spiral impressions led to higher tool load and reduced product quality despite the high efficiency of these discs. The system comprising one disc with an external conical working surface and one disc with an internal conical working surface yielded the best results with the lowest energy consumption and power demand. The findings of this study demonstrate that ball rolling using spiral discs is a promising alternative to standard skew rolling methods. Full article

This paper presents a numerical investigation into a prototype energy harvesting system utilizing airflow around a bluff-body. The system consists of a flexible cantilever beam in a flag configuration with bonded piezoelectric transducers, integrated with a nonlinear triple-well potential established by auxiliary elastic elements. Three distinct bluff-body geometries—triangular, square, and semi-circular—with characteristic heights of 20 mm and 30 mm were analyzed. Aerodynamic excitation parameters were identified using CFD simulations, comparing exact and simplified mathematical representations of the lift force. The system’s dynamical response was evaluated through bifurcation diagrams, Diagrams of Coexisting Solutions (DS), and 3D Poincaré sections for zero and variable initial conditions. The results indicate that the triangular cross-section provides the widest frequency band for high-amplitude inter-well oscillations, maximizing energy harvesting effectiveness. A key innovation of this study is the demonstration that the simplified excitation model provides sufficient accuracy for rapid engineering design while significantly reducing computational overhead. Furthermore, it highlights the practical applicability of a flag-type system integrated with flexible elements to stabilize the beam’s free end. Full article

The rapid integration of large language models (LLMs) into education has shifted research focus from questions of capability, such as what LLMs can do and how accurately—to questions of deployability, including how they can be operated effectively for many learners at once. In school environments, system reliability, scalability, and real-time responsiveness are critical, as delays or interruptions can directly reduce learner engagement, particularly during synchronous activities. This study evaluates the performance of open-source LLaMA models ranging from 1 billion to 70 billion parameters across one-, dual-, triple-, and quad-GPU configurations suitable for educational settings. Performance is assessed using four key indicators: success rate (percentage of completed requests), generation speed (tokens per second), throughput (completed responses per second), and latency (time until full response generation). These metrics were measured under progressively increasing numbers of simultaneous users to identify system capacity limits and trade-offs between model size, responsiveness, and scalability. The results indicate that smaller models (1B–3B) deliver faster, more stable performance under concurrent use, while larger models (8B–70B) experience substantial slowdowns and reduced reliability, even on high-end GPU systems. These findings suggest that effective educational deployment should prioritize empirical performance and infrastructure compatibility over model size alone. The paper concludes by proposing a practical framework to guide educators, administrators, and developers in selecting and configuring locally hosted GPU systems that balance model capability, response speed, and resource efficiency for real-time applications such as AI tutors, classroom chatbots, and automated feedback tools. Full article

Time-Sensitive Networking (TSN) with Cyclic Queuing and Forwarding (CQF) is a critical mechanism for ensuring deterministic forwarding. However, existing incremental schedulers typically rely on single-dimensional heuristics, which fail to address the coupled impact of traffic characteristics and spatiotemporal resource distribution. This limitation leads to suboptimal scheduling success, especially under complex topologies and high network loads. To address this, we propose TMCOA–MFS, a joint incremental scheduling framework that integrates the Triple-Mode Cooperative Optimization Algorithm (TMCOA) with a Multi-Feature Scheduling (MFS) strategy. The logic of our approach is twofold: First, to balance spatial resource distribution, we introduce the TMCOA—inspired by table-tennis offensive–defensive behaviors—to optimize path selection by minimizing port-load variance and escaping local optima through a three-mode population partition. Second, building upon the optimized spatial paths, the MFS strategy is employed to resolve temporal scheduling conflicts. By computing a composite priority score that accounts for path hops, offset configuration difficulty, and flow size, MFS enables a robust incremental offset search with integrated feasibility checking. Extensive simulations on benchmark functions and diverse TSN scenarios demonstrate that the TMCOA offers superior convergence and stability. More importantly, the integrated TMCOA–MFS framework significantly enhances scheduling success rates and load balancing, effectively overcoming the bottlenecks of high-load and topologically complex environments. Full article

As a complex structural form capable of simultaneously bearing upper-deck highway traffic, lower-deck highway traffic, and rail transit, the curved chord stiffened double-deck continuous steel truss bridge is distinct from traditional single-deck bridges. The spatial superposition of multiple traffic types within this structure may result in multiple components approaching their critical states concurrently. Despite prior research efforts on this structural type, the failure evolution process from local yielding to global collapse under mixed traffic loads remains ambiguous. This study addresses these questions through systematic numerical investigation of a nine-span bridge with a 300 m main span. A two-stage analytical approach is employed: a Midas/Civil analysis first identifies critically stressed regions, then ABAQUS multi-scale modeling enables refined analysis of critical components while maintaining computational efficiency. Twenty-nine combined traffic loading cases encompassing dual- and triple-category configurations are systematically analyzed. The results show that the ultimate load-carrying capacity coefficients range from approximately 7 to 18, with a minimum of 7.137, and the dual-level highway combinations exert greater influence than road–rail combinations. More importantly, three failure path convergence characteristics were discovered. First, the initial failure position under each working condition tends to be consistent, initiating at the lower chord near the top of the mid-span pier, which confirms that inherent structural defects exist at this location. Second, the gusset plate at the top of pier W6 appears as the second failure location in 48% of cases and ranks within the first four locations across all cases. Third, path similarity progressively increases with traffic diversity. Additionally, Q370qE steel exhibits 5–22% stress exceedance with variable critical locations depending on traffic conditions. Based on these convergence characteristics, a safety monitoring scheme is proposed: monitoring points need to be arranged symmetrically on both sides of the bridge on the top chords, bottom chords, web members, and wedge plates near the tops of the piers. Full article

This article examines the emergence of entrepreneurial universities within China’s innovation-driven development agenda, with Shenzhen used as a regional case through which to analyse this process. Drawing on the Triple Helix literature and its later Quadruple and Quintuple Helix extensions, this study uses a qualitative case-study design that combines policy and archival analysis, descriptive questionnaire evidence from 132 respondents, and 42 semi-structured interviews with university, industry, government and venture-capital actors. The analysis shows how Shenzhen’s innovation capacity has been built through the interaction of firm-led technological upgrading, enabling municipal governance and a gradual repositioning of universities. Rather than following the university-centred pattern often associated with mature Western innovation systems, Shenzhen displays a hybrid Helix configuration in which universities acquire entrepreneurial functions through talent provision, external partnerships, practice-oriented knowledge exchange and organisational adaptation. This article therefore contributes to debates on entrepreneurial universities by explaining how such institutions can develop in late-developing, industry-led regions where conventional research infrastructure is initially limited. It also offers policy implications for strengthening sustainable university entrepreneurship, cross-sector coordination and regional innovation resilience in emerging economies. Full article

Multijunction solar cells employing a GaInP/GaAs/Ge triple-junction configuration are the dominant technology for space photovoltaic applications. The choice of an efficient electrode is crucial in solar cells, as it enables effective charge carrier collection and transport while allowing maximum light to reach the active layer. Indium tin oxide (ITO)/graphene hybrid electrodes have emerged as smart transparent conductors offering significant advantages over conventional brittle ITO films. Graphene electrodes were prepared by cold-wall chemical vapor deposition and ITO electrodes were commercially obtained and used as a base for hybrid ITO/graphene electrodes. Raman spectroscopy confirmed the successful integration and characteristic G and 2D bands on the ITO surface. Nanoscale current mapping via Tunneling Atomic Force Microscopy (TUNA-AFM) verified continuous conductive pathways throughout the film with ~60% increase in nanoscale tunneling current at graphene/ITO interfaces, indicating improved local charge transport pathways. These results demonstrate the suitability of ITO/graphene hybrid electrodes a promising material for multijunction solar cells and other aerospace technologies. Full article

Recent advances in gene therapy have highlighted the potential of CRISPR-based gene-editing systems combined with adeno-associated virus (AAV) vectors. However, the limited packaging capacity of AAV remains a significant challenge for the simultaneous expression of Cas effector proteins and guide RNAs within a single vector. To address this limitation, we developed a compact AAV vector that enables the co-expression of Acidaminococcus sp. Cas12a (AsCpf1) and CRISPR RNAs (crRNAs) using a single bidirectional promoter derived from the mouse H1 promoter. Our single bidirectional H1 promoter supported indel formation comparable to that achieved by dual-promoter systems and facilitated scalable genome editing with single-, dual-, and triple-target configurations. Genome editing was successfully accomplished both in vitro and in vivo following AAV delivery. This study shows that our engineered compact AAV vector platform is capable of simultaneously delivering AsCpf1 and multiplexed crRNAs. Full article