Flow Direction Research Articles

Numerical study of influence of karst fracture water on heat transfer performance of borehole heat exchanger

Groundwater flow within karst fractures can significantly enhance the heat exchange efficiency between a borehole heat exchanger (BHE) and the surrounding rock. The development of artificial fractures to intensify heat transfer between the BHE and rock has emerged as a promising direction in geothermal exploration. This study presents a three-dimensional finite element simulation model that integrates fracture flow with BHE heat transfer, accounting for various characteristics of horizontal fractures. Data analysis was conducted using range analysis and multi-criteria comprehensive evaluation, based on the principles of orthogonal experiments. The results indicate: (i) Fracture water flow substantially improves BHE heat transfer performance in summer, with even the lowest-performing configuration in the orthogonal test showing a 5.36 % increase in heat transfer per unit length of the BHE (HPLU) compared to the natural control group without fractures; (ii) The influence of different fracture characteristics on BHE heat transfer performance follows this order: fracture water velocity > fracture aperture > fracture depth > fracture flow direction > fracture water temperature; (iii) The optimal configuration enhances HPLU by 16.95 % over the natural control group, demonstrating that developing well-designed artificial fractures in karst regions can substantially improve BHE heat transfer efficiency.

Impact Risk Assessment of Gravity-Based Foundation of Offshore Wind Turbine Under Tsunamis

As an important renewable engineering structure, offshore wind turbine foundation is threatened by tsunami bore. A three-dimensional numerical model of dam-break wave tsunami is established and validated based on computational fluid dynamics to study the impacting effects of gravity-based foundation (GBF) of offshore wind turbines under tsunamis. The impacting process of the small, middle, and large tsunami on the GBF is numerically simulated, and the load effects characteristics of the GBF of the wind turbine at different stages of the tsunami impact process are analyzed. The research results show that the GBF is subjected to two peak impact forces under tsunami-impacting action. The tsunami bore has a frontal impact on the GBF, and the force peak of the flow direction is the largest, which has the greatest impact on the foundation of the wind turbine. Specifically, the middle tsunami exerts a maximum frontal impact force of 16.8[Formula: see text]N, with a peak dynamic pressure of 678.2 Pa, and a maximum base moment of 1.24[Formula: see text]N[Formula: see text]⋅[Formula: see text]m. Besides, the variation on the base moment in the incident flow direction of the incoming is larger than that in the transverse direction. The research provides valuable insights into the tsunami-resistant GBF, offering recommendations and guidelines for ensuring the long-term stability of offshore wind turbines in tsunami-prone regions.

Study on Multi-Scenario Rain-Flood Disturbance Simulation and Resilient Blue-Green Space Optimization in the Pearl River Delta

In the face of global climate change and rapid urbanization, the Pearl River Delta is confronted with frequent river floods and heavy rainfall, which leads to substantial economic losses and casualties. Enhancing the role of blue-green space in rain-flood resilience is crucial for mitigating such damages in this new era. Firstly, based on an analysis of the current status quo of blue-green space in the Pearl River Delta and the identification of potential areas at risk from rain and floods, this paper elucidates that resilient blue-green space in the Pearl River Delta should be guided by a systematic, bottom-line, and forward-looking orientation while considering spatial characteristics such as multi-scale network connectivity, redundancy and diversity/multi-functionality. Secondly, an optimization route is proposed based on steps of analysis of existing blue-green space, identification of inundated areas prone to rain and flood damage and optimization of blue-green spaces. Strategies for optimizing blue-green space are put forth including enhancing water corridor connectivity, optimizing ecological barriers and corridors, as well as constructing water gates to control hydrological flow direction. Simulation results demonstrate that under similar rain-flood disaster conditions, optimized blue-green space exhibits smaller sizes and lower depths of potential inundated areas compared to the original ones.

Late-stage Deccan eruption from multiple shallow magma chambers through vertical flow along fissures: Insights from magnetic fabric analysis of the Pachmarhi dyke swarm

The Pachmarhi dyke swarm, located in the eastern part of the Narmada-Satpura-Tapi dykes belonging to the Deccan Continental Flood Basalt, are studied using the Anisotropy of Magnetic Susceptibility (AMS) technique. This research aims to determine the direction and sense of magma flow within the dykes, providing insights into the depth, number, and location of magma chambers, as well as the geodynamics of their plumbing system. Petrography and rock magnetism analyses revealed a mixture of high- and low-titanium magnetite particles, predominantly of pseudo-single domain nature (with a smaller proportion of multi-domain dominated) grains are primary remanence carriers. We identified four distinct types of magnetic fabric (I-IV) within the Pachmarhi dykes. The K1-axis being parallel to the dyke plane, and the intersection of the imbrication angle of magnetic foliation (for oblate fabric) and magnetic lineation (for prolate fabric) was used to discern the direction of magma flow. This analysis revealed multiple trends of magma flow, ranging from vertical/sub-vertical to inclined. The flow fabric provides valuable information about the presence of multiple shallow sub-crustal magma chambers. This interpretation aligns with prior independent gravity and 3-D density modelling studies, which indicates the presence of dense mafic magma bodies at depths of 4 to 8 km along the Narmada-Tapi intraplate rift zone. These findings are similar to those observed in the Nandurbar-Dhule dyke swarms in the western region of the Narmada-Satpura-Tapi dykes. Consequently, we can infer that the emplacement of dykes in the Pachmarhi region of the Narmada-Son-Lineament, which likely served as feeders for the late-stage Deccan volcanism, was primarily facilitated by a “polycentric flow” mechanism. In this process, magma was injected vertically from multiple shallow magma chambers through crustal fissures, potentially feeding into the late-stage Deccan flow units, such as the Ambenali or Mahabaleshwar Formations.

Differential tectonic activity along the southern boundary of the Qilian Mountains: Insights from low-temperature thermochronology, seismic data, and fluvial geomorphology

The Cenozoic development of the Tibetan Plateau is one of the most remarkable events in the geosciences. The southern boundary of the Qilian Mountains is a spectacular basin-mountain boundary in the northern Tibetan Plateau offering a valuable opportunity to investigate the growth processes and mechanisms of the Tibetan Plateau. Structural activity is significantly variable across the northern Qaidam basin, and the underlying reason for these differences remains uncertain. To address this issue, we undertook an analysis of two main watersheds—the Tataleng and Yuqia River watersheds—encompassing the middle section of the northern Qaidam basin. This study utilized a multidisciplinary approach combining fluvial geomorphology, low-temperature thermochronology, and seismic data to comprehensively investigate the structural activity within the northern Qaidam basin. The high channel steepness index, young low-temperature thermochronologic ages, concentrated earthquakes, and numerous knickpoints along the piedmont area of the Qaidam Shan collectively suggest that this region is among the most structurally active areas along the southern boundary of the Qilian Mountains. The varying levels of structural activity in the northern Qaidam basin could be linked to the intense glacial erosion in the Qaidam Shan during the Quaternary. Moreover, the flow orientation observed in the bedrock mountains is consistent with the N-S compressional stress field in the northern Qaidam basin during the early Cenozoic, representing a stark contrast to the modern NE-SW stress field. In this way, this research supports the understanding that river geomorphic parameters, including river steepness index and flow direction, are valuable tools for unveiling the regional tectonic evolution in bedrock mountain areas.

Microstructure Evolution and Mechanical Behavior of TiB-Reinforced Ti-6.5Al-2Zr-1Mo-1V Matrix Composites Obtained by Vacuum Arc Melting and Spark Plasma Sintering

Ti-6.5Al-2Zr-1Mo-1V/TiB metal matrix composites with 3 wt.% of TiB2 were obtained using vacuum arc melting and spark plasma sintering methods and compared with an unreinforced Ti-6.5Al-2Zr-1Mo-1V alloy. The microstructures of the unreinforced Ti6.5Al-2Zr-1Mo-1V alloy in the as-cast and as-sintered conditions were quite typical and consisted of colonies of α-lamellae embedded in the β matrix. The microstructure of the as-cast Ti-6.5Al-2Zr-1Mo-1V/TiB composite composed of TiB fibers randomly distributed within the two-phase α/β matrix, while the as-sintered composite had a network-like microstructure, in which areas of the two-phase α/β matrix were delineated by walls of TiB fibers. At room temperature, the yield strength of the as-cast and as-sintered Ti-6.5Al-2Zr-1Mo-1V alloy were 800 and 915 MPa, respectively, with a plasticity of 18% in both conditions. The addition of TiB fibers contributed to a ~40 and 50% strength increment, with values of 1100 and 1370 MPa for the as-cast and as-sintered composites, respectively. In the as-sintered composite, the strengthening effect reduced at 400 °C and almost disappeared at elevated temperatures of 800–950 °C. The as-cast composite showed much higher strength during warm and hot deformation—at 800–950 °C, the yield strength of the as-cast composite was 50% higher compared to the Ti-6.5Al-2Zr-1Mo-1V unreinforced alloy. A higher rate and degree of globularization were established for the as-cast composite compared to the unreinforced alloy. For the as-sintered composite, a noticeably lower rate and degree of globularization was shown. During hot compression of the as-cast composite, TiB fibers reoriented towards the metal flow direction, while the network microstructure formed in the as-sintered composite transformed into clusters of borides unevenly distributed within the matrix. Based on the obtained results, the apparent activation energy of plastic deformation was calculated, and the operating deformation mechanisms were discussed both for the as-cast and as-sintered composites. The Arrhenius flow stress model and the dynamic material model were used to evaluate the deformation behavior of composites beyond the experimentally studied temperatures and strain rates.

Thermal Performance of a Straw Bale Building in Relation to Fiber Orientation: A Case Study

In the face of escalating global average temperatures, it is urgent to identify mechanisms that can significantly curtail the emission of greenhouse gases. The construction industry plays a pivotal role in shaping these emissions, rendering the selection of environmentally conscious materials indispensable in the imminent future. In this context, attention is drawn to an interesting material from an ecological point of view: straw. Abundant as a natural byproduct exhibiting remarkable thermal properties, straw emerges as a good candidate for sustainable edification. In the present work, an in situ study of its thermal resistance is carried out, and it is found that it allows stable interior temperatures. The apparent thermal conductivity is analyzed in relation to the orientation of its fibers in the same building, and its low conductivity compared with traditional construction materials is confirmed. The relevance of this work lies in the fact that the building studied contains walls with different fiber orientations in the same room, with the same ambiental conditions. This ensures that the different thermal behaviors are exclusively due to the orientation of the fibers. When considering both orientations of the fibers, different values of thermal conductivity are discerned. Conductivity decreases when the direction of the heat flow is perpendicular to the fibers. However, due to the inherent geometry of the bales, their overall thermal behavior ultimately proves comparable.

Entrepreneurial back-to-landers: Neo-farmers in Turkey

Urban-to-rural migration, particularly back-to-land migration, has become prominent in Turkey. This paper focuses on entrepreneurial back-to-landers or neo-farmers, who have migrated to rural areas specifically to get into commercial agriculture and farming. Through an analysis of semi-structured interviews with 72 neo-farmers, the paper identifies six critical attributes that aid them during entry into farming and later on, when they are running successful farm businesses: possession of financial wealth; ownership of agricultural land; familiarity with agro-food sectors; education (in agricultural and/or food sciences); experience with corporate conduct; and active connections to the local and/or national organizations associated with the food movement. The paper argues that these attributes feature entrepreneurial skills, experience and connections, which in turn provide neo-farmers with economic, social, and cultural capital and comparative advantages to run their farm businesses. Through the case, the paper shows that one, the direction of capital flows, which historically has been rural-to-urban, may change to urban-to-rural (and from non-agricultural sectors to agriculture) through entrepreneurial back-to-land migration; and two, entrepreneurial skills have become vital for smallholders – newcomer or continuer – if agriculture is going to be their primary income generating activity.

Fractured rocks influence on hydrological flow in of the Agourai plateau, Middle Atlas, Morocco: Inferences from Isobase lineaments and field data

This study provides new data of hydrological flow direction in the Agourai plain, Tabular Middle Atlas, north central Morocco. Given its major economic interest in term of agricultural production, the analysis of fracture networks remain essential for a good management of water resources. Mapping fractures network, using isobase maps combined with field data reveal three groups of fractures oriented N-S, NE-SW and NW SE. the latter was poorly described and lies with the setting of three main springs in the area. Fractures analysis in the Bouchermou spring, confirm the predominance of NW direction, which control of the water flow in this area.

Flow of viscoelastic films over grooved surfaces with partial wetting

We consider the steady flow of a viscoelastic film over an inclined plane featuring periodic trenches normal to the main flow direction. The trenches have a square cross-section and side length 5–8 times the capillary length. Owing to the orientation of the substrate, the film fails to coat the topographical feature entirely, forming a second gas–liquid interface inside the trench and two three-phase contact lines at the points where the free surface meets the wall of the trench. The volume of entrapped air depends on material and flow parameters and geometric conditions. We develop a computational model and carry out detailed numerical simulations based on the finite element method to investigate this flow. We solve the two-dimensional mass and momentum conservation equations using the exponential Phan-Thien & Tanner constitutive model to account for the rheology of the viscoelastic material. Due to the strong nonlinearity, multiple steady solutions possibly connected by turning points forming hysteresis loops, transcritical bifurcations and isolated solution branches are revealed by pseudo-arc-length continuation. We perform a thorough parametric analysis to investigate the combined effects of elasticity, inertia, capillarity and viscosity on the characteristics of each steady flow configuration. The results of our simulations indicate that fluid inertia and elasticity may or may not promote wetting, while shear thinning and hydrophilicity always promote the wetting of the substrate. Interestingly, there are conditions under which the transition to the inertial regime is not smooth, but a hysteresis loop arises, signifying an abrupt change in the film hydrodynamics. Additionally, we investigate the effect of the geometrical characteristics of the substrate, and our results indicate that there is a unique combination of the geometry and viscoelastic properties that either maximizes or minimizes the wetting lengths.

Experience of patent ductus arteriosus ligation during extracorporeal membrane oxygenation treatment in newborns with severe respiratory failure due to persistent pulmonary hypertension: a single-center retrospective study

BackgroundThe aim of this study is to summarize our center’s experience with patent ductus arteriosus (PDA) ligation during extracorporeal membrane oxygenation (ECMO) treatment in newborns with severe respiratory failure due to persistent pulmonary hypertension of the newborn (PPHN).MethodsWe retrospectively collected and analyzed clinical data from five newborns with severe respiratory failure due to PPHN who underwent PDA ligation during ECMO treatment at our hospital between January 2021 and August 2023.ResultsAll five patients had large PDAs, measuring 10 mm, 6 mm, 6 mm, 7 mm, and 6 mm, respectively. Significant left-to-right shunting through the PDA was observed after 29 h, 14 h, 3 h, 7 h, and 5 h of ECMO treatment, respectively, at which point successful PDA ligation was performed. The surgical durations were 52 min, 45 min, 55 min, 50 min, and 40 min, respectively. Post-ligation, blood lactate levels significantly decreased compared to preoperative values. Four patients were successfully weaned off ECMO, with ECMO support durations of 64 h, 92 h, 70 h, and 87 h, respectively. After ECMO removal, mechanical ventilation was discontinued after 5.2 days, 7.2 days, 9.5 days, and 5.5 days, respectively. None of the four surviving patients experienced complications such as residual shunting, bleeding, chylothorax, neurologic injury, pneumothorax, poor wound healing, or sepsis.ConclusionDuring ECMO treatment for PPHN in newborns with large PDAs, the direction of blood flow through the PDA should be closely monitored. PDA ligation is a feasible and reasonable intervention when pulmonary artery pressure decreases and left-to-right shunting through the PDA becomes evident.

Enhancement of heat transfer using elliptical twisted inner pipe with convergent conical ring turbulator for turbulent flow in double pipe heat exchanger

This study focuses on evaluating the impact of a fully twisted inner pipe along with conical rings turbulator by conducting a numerical analysis of the double-pipe heat exchanger (DPHE), considering both parallel and counterflow configurations for heat transfer. As modification, a straight elliptical pipe compared with two other pipes with three twists and full twists along their lengths is also investigated to compute the heat transfer rate, pressure drop, and turbulence characteristics. Modelling has been performed using ANSYS Fluent, considering the RNG k-ε turbulence model. The regime of turbulent flow is studied within the range of Reynolds numbers from 5,000 to 26,000. Validation has been conducted comparing with the experimental studies, and reasonable agreement has been observed. The full twists effect generates a swirling motion, and conical rings are inserted inside the outer pipe as a passive turbulator to guide the flow towards the inner pipe, where the hot fluid passes. Comparing the results, the inner twisted pipe with the conical ring exhibits a significant improvement in the Nusselt number (Nu), reaching 445 in the counterflow direction with the six rings. The evaluation of entropy generation is described as a function of frictional and thermal contributions. According to the findings, turbulators slightly increase entropy development. Analysis of total entropy generation shows that, because of the high viscosity, frictional entropy generation is dominant. Also, when the vortex flow becomes stronger, the total entropy creation rate decreases down. The Performance Evaluation Criteria (PEC) is also greater than 1 for both parallel and counterflow flow, indicating that enhancement of the rate of heat transfer, outweighs the decrease in pressure drop. Particularly in counterflow directions the PEC is 2.3 which is impressive. Overall, full twists along the pipe lengths enhance the heat exchanger's performance, and full twists with six conical rings fortify most in both flow directions.

Investigating the efficacy of uncrosslinked porcine collagen coated vascular grafts for neointima formation and endothelialization.

This study evaluates the efficacy of uncrosslinked porcine collagen coated vascular grafts (UPCCVG) in facilitating neointima formation and endothelialization. Prior to coating, the uncrosslinked porcine collagen underwent comprehensive characterization employing SDS-PAGE, image analysis, circular dichroism and immunogenicity. The PET substrate of the vascular graft was coated with collagen solution utilizing the dip-coating method. Water permeability, blood leakage resistance, radial compliance, hemolysis, cytotoxicity and cell proliferation of UPCCVG in vitro were studied. Subsequent in vivo evaluation involved the implantation of UPCCVG as a substitute for the porcine abdominal aorta. Digital subtraction angiography (DSA) was employed to evaluate UPCCVG patency post-implantation, while histology, immunohistochemistry, and scanning electron microscopy were utilized to assess neointima formation and endothelialization. The in vivo thrombosis of UPCCVG was analyzed simultaneously to further characterize its blood compatibility. The uncrosslinked collagen demonstrated high purity, maintaining its triple helix structure and molecular weight akin to the type I bovine collagen standard substrate, indicative of preserved biological activity and low immunogenicity. UPCCVG exhibited water permeability, blood leakage resistance, radial compliance and blood compatibility comparable to commercial grafts. DSA revealed satisfactory patency of UPCCVG without evidence of stenosis or swelling at the 3-week post-implantation mark. Histological analysis illustrated well-developed neointima with appropriate thickness and controlled proliferation. Immunohistochemistry confirmed the presence of endothelial cells (VWF positive) and smooth muscle cells (α-SMA positive) within the neointima, indicating successful endothelialization. Moreover, the morphology of the neointima surface closely resembled that of the natural artery tunica intima, oriented along the direction of blood flow. UPCCVG, composed of uncrosslinked porcine collagen, demonstrates promising potential in fostering neointima formation and endothelialization while mitigating intimal hyperplasia. This biocompatible uncrosslinked porcine collagen merits further investigation for its clinical applications in vascular reconstruction.

Experimental study on the electrical conductivity and strain sensitivity of fibre-reinforced thermoplastic for structural health monitoring

This experimental study explores the mechanical, electrical, and piezometric characteristics of conductive thermoplastic polymers reinforced with short carbon and glass fibres. The work investigates how the local anisotropy induced during the manufacturing injection process impacts the properties of the composite. Tensile tests showed that the material orientation respect to the injection flow direction significantly affects the mechanical properties due to the alignment of the fibres with the injection flow, as shown through microscopy analysis. Contrarily, electrically conductive tests showed that the influence of the orientation on the conductive properties of the material is negligible. The study also unveils the difference in the surface and bulk conductivity with the increasing distance of the electrodes. Tensile tests with in-situ electrical measurements were conducted to assess strain sensitivity by correlating stress–strain curves with changes in material conductivity. The results demonstrate the predominant impact of local anisotropy on piezometric response. Finally, a model for the piezometric response of the material is proposed and applied for the structural health monitoring of a tensile specimen, revealing its ability to detect local damage before final failure. This application underscores the prognostic capabilities of this material and its potential significance in ensuring structural integrity.

A Microscopic Experimental Study on the Dominant Flow Channels of Water Flooding in Ultra-High Water Cut Reservoirs

The water drive reservoir in Shengli Oilfield has entered a stage of ultra-high water cut development, forming an advantageous flow channel for the water drive, resulting in the inefficient and ineffective circulation of injected water. Therefore, the distribution characteristics of water drive flow channels and their controlled residual oil in ultra-high water cut reservoirs are of great significance for treating water drive dominant flow channels and utilizing discontinuous residual oil. Through microscopic physical simulation of water flooding, color mixing recognition and image analysis technology were used to visualize the evolution characteristics of water flooding seepage channels and their changes during the control process. Research has shown that during the ultra-high water content period, the shrinkage of the water drive seepage channel forms a dominant seepage channel, forming a “seepage barrier” at the boundary of the dominant seepage channel, and dividing the affected area into the water drive dominant seepage zone and the seepage stagnation zone. The advantage of water flooding is that the oil displacement efficiency in the permeable zone is as high as 80.5%, and the remaining oil is highly dispersed. The water phase is almost a single-phase flow, revealing the reason for high water consumption in this stage. The remaining oil outside the affected area and within the stagnant flow zone accounts for 89.8% of the remaining oil, which has the potential to further improve oil recovery in the later stage of ultra-high water cut. For the first time, the redundancy index was proposed to quantitatively evaluate the control effect of liquid extraction and liquid flow direction on the dominant flow channels in water flooding. Experimental data showed that both liquid extraction and liquid flow direction can regulate the dominant flow channels in water flooding and improve oil recovery under certain conditions. Microscopic physical simulation experiments were conducted through the transformation of well network form in the later stage of ultra-high water content, which showed that the synergistic effect of liquid extraction and liquid flow direction can significantly improve the oil recovery effect, with an oil recovery rate of 68.02%, deepening the understanding of improving oil recovery rate in the later stage of ultra-high water content.

Structural and dynamic characteristics of horseshoe vortex systems in front of rigid vegetation inclined upstream under conditions of overland flow

Inclined angle significantly impacts horseshoe vortex (HV) system and subsequent flow events upstream of vegetation stems, which are crucial for understanding of erosion mechanisms and geodynamics. Flume experiments were conducted to investigate dynamic characteristics of horseshoe vortex (HV) system upstream of inclined rigid vegetation stems under shallow overland flow conditions. Five inclination angles (10°, 20°, 30°, 40°, 50°) were tested alongside a vertical column (0°) across four low Reynolds number conditions (ReD = 2995–4639). Using high-precision particle image velocimetry (PIV) system, we measured the flow field in upstream symmetry plane of the cylinder. Then time-averaged primary HV features were analyzed in terms of the location, radius, vorticity, swirling strength, flow direction and vertical velocity. The increasing inclination angle weakens the formation of the HV system. This is evident in the decrease of vorticity and swirling strength, as well as the gradual diffusion and eventual rupture of the HV system. In the horizontal direction, the primary HV gradually moves away from the cylinder, with minimal vertical impact. The radius of the main HV is positively correlated with the tilt angle, while vorticity and rotation intensity are negatively correlated. We also examined the time-resolved characteristics of the velocity components. The probability density functions (PDFs) of streamwise and vertical velocity components show asymmetric double peaks, indicating two high-frequency events: backflow and downwelling. Linear random estimation revealed that the backflow event is driven by a high-momentum counter current passing through the primary HV, which is mainly dominated by a backflow mode, while the downwelling event arises from low-momentum fluid that cannot penetrate the HV, dominated by a zero-flow mode. These two modes exhibited minimum and maximum time percentages within the current time range, highlighting erosion dynamics from the perspectives of flow event frequency and momentum theory.

The limits of diplomacy by treaty: Evidence from China's bilateral investment treaty program

AbstractThe web of over 3000 Bilateral Investment Treaties (“BITs”) is the primary body of international law regulating cross‐border investments. Research suggests that these treaties may have had a limited impact on promoting new investments, but that they still may have helped to improve countries' political relationships. In this paper, we document that this pattern was reversed for one of the most prolific signers of BITs: China. Using a stacked‐event research design, we find that Chinese BITs are associated with an increase in Bilateral Foreign Direct Investment Flows but a divergence in voting patterns at the United Nations. We then explore two explanations for why the Chinese BIT program led to increased investment while also producing foreign policy divergence: that the domestic political costs of economic engagement with China push countries away, and that there are offsetting international pressures that have stronger pulls than China's efforts. We find no support for the domestic political costs explanation, but we do find evidence that the countries that received increased aid from the United States after signing a Chinese BIT had greater foreign policy divergence with China.

How to Effectively Cool Blade Batteries in Extreme High-Temperature Environments?

The market share of blade batteries is rising rapidly due to their high energy density, efficient space utilization, and low cost. Nevertheless, effective cooling solutions for blade batteries are crucial to ensure the safe operation of electric vehicles, especially in extreme high-temperature environments. This paper numerically investigates the effects of a cooling plate and the blade battery parameters on maximum battery temperature, maximum temperature difference, and cooling water pressure drop. Additionally, the energy efficiency of these solutions under various cooling demands is analyzed. The numerical results show that increasing the channel number and changing the flow direction does not significantly improve the cooling performance of the cooling plate. Moreover, the effect of cooling water temperature on the maximum temperature difference in blade batteries is negligible. Furthermore, increasing the cooling water mass flow rate and the rotational speed of the cooling fan is preferred when Tmax − Ta > 6 K, while reducing the cooling water temperature is more energy-efficient when Tmax − Ta < 6 K. These results are expected to offer theoretical guidance and data support for designing cooling systems for blade batteries in extreme high-temperature environments.

AI-Driven Neuro-Monitoring: Advancing Schizophrenia Detection and Management Through Deep Learning and EEG Analysis

Schizophrenia is a complex neuropsychiatric disorder characterized by disruptions in brain connectivity and cognitive functioning. Continuous monitoring of neural activity is essential, as it allows for the detection of subtle changes in brain connectivity patterns, which could provide early warnings of cognitive decline or symptom exacerbation, ultimately facilitating timely therapeutic interventions. This paper proposes a novel approach for detecting schizophrenia-related abnormalities using deep learning (DL) techniques applied to electroencephalogram (EEG) data. Using an openly available EEG dataset on schizophrenia, the focus is on preprocessed event-related potentials (ERPs) from key electrode sites and applied transfer entropy (TE) analysis to quantify the directional flow of information between brain regions. TE matrices were generated to capture neural connectivity patterns, which were then used as input for a hybrid DL model, combining convolutional neural networks (CNNs) and Bidirectional Long Short-Term Memory (BiLSTM) networks. The model achieved a performant accuracy of 99.94% in classifying schizophrenia-related abnormalities, demonstrating its potential for real-time mental health monitoring. The generated TE matrices revealed significant differences in connectivity between the two groups, particularly in frontal and central brain regions, which are critical for cognitive processing. These findings were further validated by correlating the results with EEG data obtained from the Muse 2 headband, emphasizing the potential for portable, non-invasive monitoring of schizophrenia in real-world settings. The final model, integrated into the NeuroPredict platform, offers a scalable solution for continuous mental health monitoring. By incorporating EEG data, heart rate, sleep patterns, and environmental metrics, NeuroPredict facilitates early detection and personalized interventions for schizophrenia patients.

Impact of Microtopography and Neighborhood Effects on Individual Survival Across Life History Stages.

Understanding drivers of plant community assembly and individual survival in forest ecosystems is crucial for effective conservation and management. While macro-scale factors influencing vegetation patterns are well documented, the combined impact of microtopographic variations and neighborhood effects at neighborhood scales, particularly in subtropical forests, requires further study. To contribute to this area of research, we established a 9.6 ha dynamic plot in a subtropical evergreen broad-leaved forest to examine the interplay between microtopographic factors and neighborhood effects on individual plant survival across different life stages. We conducted a comprehensive analysis of microtopographic variables and neighborhood effects, with individual plant survival censused through repeated surveys at 5-year intervals. Mixed-effects models were employed to assess the combined influence of these factors across life stages. Our results reveal that both microtopographic factors and neighborhood effects significantly influence plant survival, with their impacts varying across life stages. Water availability, represented by flow direction, emerged as a consistently critical factor throughout all life stages. Elevation and the topographic position index showed significant positive effects on survival, particularly in later life stages, possibly reflecting adaptations to light acquisition and water drainage. The influence of topographic factors intensified with succession, while the impact of neighborhood effects, particularly asymmetric competition and conspecific negative density dependence, changed as plants matured. This study enhances our understanding of forest community assembly, emphasizing the importance of considering abiotic and biotic factors across multiple scales for effective forest conservation and management. It provides insights into mechanisms driving spatial variation in community composition, crucial for preserving biodiversity in heterogeneous forest landscapes.