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Environmental barrier coating (EBC) can reduce the environmental susceptibility of turbine blades due to the increasing problems of high temperature oxidation and vapor corrosion in heating parts of aeroengine made by SiC/SiC. However, in addition to high-temperature corrosion, EBC may be subject to solid particle erosion (SPE) due to sands and peeled coatings. The erosion mechanism is insufficiently studied, and the impact erosion to SiC/SiC is seldom noticed. In this paper, the SPE behavior of SiC/SiC prepared by chemical vapor infiltration (CVI), which was coated with Si/Yb 2 Si 2 O 7 /Yb 2 SiO 5 rare earth silicate EBC prepared by atmospheric plasma spraying (APS), was studied, and the EBC-SiC/SiC were impacted in normal direction by SiO 2 particles with multiple particle sizes and flow rates. Scanning electron microscope (SEM) was used to observe the damage morphology, and the effects of different flow rates, energies and particle sizes on the SPE behaviors of EBC-SiC/SiC were analyzed. A meso-scale model of progressive damage method - finite element method (PDM-FEM) was built and the SiO 2 particle erosion mechanism for single layer SiC/SiC was simulated, analyzed and compared with the experimental results. [ABSTRACT FROM AUTHOR]

The Yadong-Gulu rift (YGR) is the most prominent and seismically active of the seven main ∼ NS-trending rifts in southern Tibet. Although the morphology of the southern YGR clearly indicates it has witnessed large earthquakes in the past, and despite its significant late Quaternary throw rates of ∼1 mm/yr, no large historical or instrumental earthquakes have been reported, including in the southernmost Pagri half-graben, in contrast to the northern part of the rift which is highly seismically active. Here, geomorphic characteristics helped us constrain the timing of a paleoearthquake that produced surface ruptures along the Pagri half-graben, used to document its past activity and evaluate its seismic hazard. We demonstrate that the co-seismic surface ruptures extend for ∼65 km along the Yadong normal fault, with a maximum vertical displacement ranging from 2 to 4.0 ± 0.1 m. Based on empirical relationships between magnitude, surface rupture length, and fault displacement, we suggest that this event may correspond to a M w 6.9–7.2 earthquake. Combined with previous studies, our radiocarbon (14C) and Optically Stimulated Luminescence (OSL) ages from three pits within the earthquake wedge across the surface ruptures constrain the paleoearthquake timing at 3470-2056 years BP. We suggest that the southern YGR currently has a high regional seismic hazard for a M w 6.8–7.1 earthquake, considering the significant throw rates and long timespan since the last strong event. Furthermore, we suggest that such different seismic activity and throw/extension rates between the southern and northern YGR may be explained by different upper crustal rheology behavior and mid-crustal structure. • Co-seismic surface ruptures (last earthquake?) in Pagri half-graben of Yadong rift date from 3470 to 2056 yrs BP. • Ruptures extend for ∼65 km with maximum vertical displacement of 2–4 m, corresponding to a paleoearthquake of M w 6.9–7.2. • Distinct extension rates and upper crustal structures between north and south YGR may explain their different seismic activity. [ABSTRACT FROM AUTHOR]

Various types of pile driving work may induce high-intensity ground-borne vibrations. Predicting vibration intensity before adopting mitigation measures is vital for minimizing the impact of vibration on nearby structures and occupants. Vibratory pile driving is a commonly applied foundation construction method. However, numerical simulation models for ground vibrations during a complete process of vibratory driving have rarely been studied. This study introduces an axisymmetric finite element model that utilizes the arbitrary Lagrangian-Eulerian technique to simulate the continuous vibratory driving of a circular closed-ended pile penetrating from the ground surface to a target depth. The model validity was confirmed by assessing the calculated ground vibrations against the findings documented in earlier research. The results showed that the critical penetration depth of piles, at which the maximum peak particle velocity (PPV) occurs, varied with the radial distance and depth of points of interest, contradicting a common preconception. Moreover, the maximum PPV did not always occur on the ground surface across all radial distances. Parametric analysis revealed that an increase in the soil cohesion strength, pile diameter, or soil-pile friction, or a decrease in the driving frequency or soil damping ratio would increase ground vibrations due to vibratory pile driving. • Traditional simulations of vibratory piling cannot reliably predict the max PPV. • ALE-enabled FE modelling is developed to simulate continuous vibratory piling. • The model's validity is confirmed by the findings documented in earlier research. • The maximum PPV does not always occur on the ground surface. • Parameters affecting ground vibrations are systematically investigated. [ABSTRACT FROM AUTHOR]

Channel Pruning is one of the most widespread techniques used to compress deep neural networks while maintaining their performances. Currently, a typical pruning algorithm leverages neural architecture search to directly find networks with a configurable width, the key step of which is to identify representative subnet for various pruning ratios by training a supernet. However, current methods mainly follow a serial training strategy to optimize supernet, which is very time-consuming. In this work, we introduce PSE-Net, a novel parallel-subnets estimator for efficient channel pruning. Specifically, we propose a parallel-subnets training algorithm that simulate the forward–backward pass of multiple subnets by droping extraneous features on batch dimension, thus various subnets could be trained in one round. Our proposed algorithm facilitates the efficiency of supernet training and equips the network with the ability to interpolate the accuracy of unsampled subnets, enabling PSE-Net to effectively evaluate and rank the subnets. Over the trained supernet, we develop a prior-distributed-based sampling algorithm to boost the performance of classical evolutionary search. Such algorithm utilizes the prior information of supernet training phase to assist in the search of optimal subnets while tackling the challenge of discovering samples that satisfy resource constraints due to the long-tail distribution of network configuration. Extensive experiments demonstrate PSE-Net outperforms previous state-of-the-art channel pruning methods on the ImageNet dataset while retaining superior supernet training efficiency. For example, under 300M FLOPs constraint, our pruned MobileNetV2 achieves 75.2% Top-1 accuracy on ImageNet dataset, exceeding the original MobileNetV2 by 2.6 units while only cost 30%/16% times than BCNet/AutoAlim. • We propose PSE-Net, a novel parallel-subnets estimator for efficient channel pruning. • The prior-distributed-based sampling algorithm to facilitate subnets search. • 30%/16% total time for estimator training compared with BCNet/AutoSlim. • Exceeds the SOTAs on ImageNet and downstream tasks for a variety of FLOPs budgets. [ABSTRACT FROM AUTHOR]

This paper examines the impacts of road network density on motor vehicle travel through traffic flow and network analysis of cities in China from three perspectives: multi-city comparison with traffic flow data, multi-city and multi-period comparisons with structural characteristics. When we examine the correlation between road network density and traffic flow characteristics including the travel time and speed of 35 major cities in China, no correlation exists between them which may result from different network structures, dynamic traffic demands, traffic control plans, driving behaviors, and so on. It inspires us to explore the correlation between road network density and static travel indicators. Then structural characteristic of road networks can be treated as a fixed relatively attribute and becomes the next research emphasis of this work. Comparative analysis results of three current cities (Xiamen, Washington D.C., San Jose) indicate that the average travel distance in different cities with the similar land area will not increase significantly as road network density increases. Results of an analysis of road network evolution of Changchun, China show that the increase of road network density shortens the average road segment length as well as travel distance in general. This impact on average travel distance is also related to evolution periods or modes of urban road networks. These findings provide important empirical support for planners and policymakers to understand the impacts of road network density on transport performance and design more effective urban road networks. [ABSTRACT FROM AUTHOR]

As a common construction activity, rock excavation using hydraulic breakers often generates high-level ground- and structure-borne vibrations, which may adversely affect nearby buildings in terms of structural safety, occupant comfort, and ultraprecision equipment functionality. However, building vibrations induced by rock excavation have not been well investigated and understood in the literature. For example, the coupling attenuation at column bases and the floor-to-floor vibration attenuation inside a building have rarely been quantitatively studied. Moreover, traditional dynamic analysis methods in earthquake engineering may not apply to simulations of rock excavation-induced building vibrations. This paper proposed a novel assessment framework based on the mechanical impedance concept, which can quantify the coupling attenuation at column bases and the floor-to-floor vibration attenuation inside a building in a computationally efficient manner. Systematic finite element simulations of rock excavation were performed to characterize vibration propagation in the ground and buildings. The finite element simulations and field measurements successfully verified the accuracy of the proposed prediction formulas, which offers a convenient vibration impact assessment framework to construction practitioners. • Traditional seismic analysis methods are not applicable to the simulations of construction-induced building vibrations. • The mechanical impedance concept is adopted to derive a new computation and assessment framework. • The framework considers two main wave division mechanisms: column base coupling attenuation and floor-to-floor attenuation. • The impedance-based method is simple and efficient for vibration predictions and vibration impact assessment for buildings. • The proposed method is verified through numerical simulations and field measurements. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose a general power model along with a versatile optimization methodology that can be applied to different applications for minimizing service delay while satisfying power budget in data centers. We test our methodology on two totally different applications from both cloud computing and enterprise scenarios. Our solution is novel in that it takes into account the dependence of power consumption on temperature, attributed to temperature-induced changes in leakage current and fan speed. While this dependence is well-known, we are the first to consider it in the context of minimizing service delay. Accordingly, we implement our optimization strategies with Hadoop, Tomcat, and MySQL on a 40-node cluster. The experimental results show that our solution cannot only limit the power consumption to the power budget but also achieves smaller delay against static solutions and temperature oblivious DVFS solutions. [Copyright &y& Elsevier]

• Measured ground vibrations on construction sites are used to locate impact sources. • Using square layout or increasing monitoring points improves localization accuracy. • A two-stage method improves localization accuracy for deep impact sources. • Localized impact sources and empirical formula enable global vibration assessment. Excessive ground-borne vibrations induced by construction activities may pose adverse effects on the surrounding environments. On-site vibration control is typically based on vibration monitoring results at a few selected locations. However, this approach cannot predict vibration intensities at locations other than the monitored points because the locations of vibration sources are usually unknown in vibration assessment processes. The localization of impact sources (e.g., impact piling) becomes a critical problem to be addressed before vibration intensities can be quantified in a broad area instead of at several discrete points. Therefore, this paper develops a two-stage impact source localization method based on wave propagation characteristics obtained in finite element analyses of an infinite half-space soil domain. The localization accuracy of this approach is validated by numerical examples and field experiments on a construction site with ongoing impact piling work. The results indicate that the plan coordinates of the impact sources can be localized with satisfactory accuracy. The variations of the measured vibration intensities along with the distance from the localized impact source are modeled by using an empirical formula. The estimated impact source locations and the obtained empirical formula can jointly extend vibration intensity assessment from the discrete monitored points to the global surrounding area. [ABSTRACT FROM AUTHOR]

While the structural deformation at the Arabia-Anatolia-Africa junction is critical for understanding eastern Mediterranean tectonics, it remains debatable (extensional or compressional). Field survey of the 2023 Mw7.7 Pazarcik earthquake surface rupture along the Amanos Range, and microstructure and composition analyses of related fault rock were performed to investigate this issue. The surface rupture shows transtensional branches, with the main and secondary strands displaying sinistral (normal) offsets of 2.0–4.0 (0.4–0.9) and 1.0 (0.2) m. Slip plane of the secondary fault is marked by a ∼20 cm wide extensional fracture dividing fault breccia from gouge. Meanwhile, the gouge (26 % calcite, 38% serpentine and 36% smectite) is also dominated by tension cracks microscopically. In contrast to the widespread extensional deformation, geological evidence imply that this fault had experienced reverse slip in the Quaternary, as shown by thrusting of serpentine onto alluvium and the consistency of R foliations with reverse shear. We interpret it as the SW continuation of the East Anatolia fault (EAF) that was formerly characterized by transpressional deformation, and reactivated transtensionally due to the change of fault strike during this earthquake. In the broader Mediterranean tectonics framework, the Amanos segment might be interpreted as a recently formed component linking the Karasu fault to the EAF. • The coseismic rupture along the Amanos Range is overall transtensional. • The largest branch fault reactivated was previously transpressional. • This transformation happened in the Quaternary. • It highlights the tectonic evolution in the Arabia-Anatolia-Africa junction zone. [ABSTRACT FROM AUTHOR]

The measured dose was shown to be dependent on the angle of beam incidence and influenced by couch absorption when a 2D detector was used in a stationary phantom. The use of a 2D array (MatriXX) in combination with a solid water phantom (RW3) dose verification system was explored, which could take into account the couch absorption influences, generate correction factors (CFs) for each detector element, and also calibrate the measured dose for accurate validation of intensity-modulated arc therapy (IMAT) treatment plans. Based on the introduction of a homogeneous treatment bed model in the Monaco treatment planning system, CFs(θ) were constructed for all incidence angles using 6 MV photon lines in a 28 cm × 28 cm field for MatriXX at different field incidence angles (0°–360°) as a relative ratio of simulated and measured values. The accuracy of the 2D array in combination with the solid water phantom (MatriXX/RW3) was systematically investigated by verifying 12 IMAT plans with and without CFs. In addition, the resulting assessments were evaluated by 40 additional IMAT plans of different tumor sites, using the COMPASS three-dimensional (3D) dose validation device measurements as a benchmark. After correction based on CFs(θ), the effect of the mean pass rates (3%/3 mm) of the MatriXX 2D array for 12 IMAT plan QA can be seenan explicit improvement of 6.1% was observed with the CFs(θ). The average pass rate increased from 92.0% to 98.1%, and the additional 40 IMAT plans QA γ(3mm/3%) matched well between COMPASS and the measurements for MatriXX/RW3, with CFs(θ)'s of 98.4 ± 1.5 vs. 99.1 ± 0.9 for the phantom plans. For different tumor sites, the cervical, thoracic, and abdominal cases for the 3D COMPASS validation devices were 97.9 ± 1.5 vs. 99.4 ± 0.3, 99.1 ± 0.9 vs. 98.6 ± 1.6, and 98.7 ± 0.9 vs. 99.3 ± 0.7, respectively, with P = 0.051, 0.420, and 0.175. For head tumors, the 2D MatriXX validation pass rate was slightly lower than 3D COMPASS (97.7 ± 2.0 vs. 99.2 ± 0.5, P = 0.048). The combination of MatriXX with the solid water RW3 phantom and CFs(θ)'s incorporation of the main couch model (iBEAM evo Couchtop EP) proved to be a fast and reliable method for pre-treatment verification of arc therapy with sufficient accuracy. Slight deviations were found for patients with head tumors treated with the treatment bed extension plate assembly iBEAM® evo Extension 415. These could be minimized by constructing the extension plate couch model and then reconstructing the MatriXX/RW3 calibration factor. • A 2D array in combination with RW3 phantom dose verification system was explored. • Correction factors (CFs) were developed to calibrates the measured dose. • Measurements with and without CFs were compared with simulations in Monaco TPS. • CFs were also evaluated using the COMPASS as a benchmark by 40 additional IMAT plans. [ABSTRACT FROM AUTHOR]

High on-aspirin platelet reactivity (HAPR) has been associated with compromised aspirin efficacy in patients with diabetes suffering from acute cardiovascular events, but the key mechanisms remain elusive. The objective of this study was to uncover the potential link between pathogenic accumulation of salicylic acid (SA), the major metabolite of aspirin, and HAPR in diabetic state. Aspirin failed to inhibit platelet CD62P expression and thromboxane (TX) B 2 /6-keto-prostaglandin（PG）F 1α ratio in a type 2 diabetes mellitus (T2DM) mice model, particularly in the female, which were unanimously accompanied by significantly higher plasma SA concentrations. Pre-administration with SA increased both platelet CD62P expression and TXB 2 /6-keto-PGF 1α ratio in female T2DM mice, while pretreatment with NaHCO 3 caused the opposite effect. On the in vitro human umbilical vein endothelial cells (HUVECs)-platelet interaction assay, SA suppressed inflammation-induced cyclooxygenase-2 upregulation on HUVECs and attenuated their inhibitory effect on platelet aggregation in a dose-dependent manner. The prolonged retention of SA in diabetes may be partially explained by the downregulation of various SA efflux transporters in the kidney and the decreased urine pH. Importantly, in female aspirin non-responsive patients, the trough plasma concentration of SA are markedly increased with T2DM treated with long-term aspirin, and TXB 2 /6-keto-PGF 1α ratio and uric acid level in plasma are positively correlated with SA concentration. Our findings support that the accumulation of SA represents an important factor in causing HAPR in diabetes, and that targeting impaired SA excretion may become a novel intervention strategy to diabetes-associated HAPR. [ABSTRACT FROM AUTHOR]

Modern communication systems require high linearity, usually in addition to high output power. High linearity requires a flat device transconductance ( g m ) vs. gate-source voltage (V gs ), while at the same time, transconductance must be high for high gain. In spite of much research to investigate device/system linearity, GaN high electron mobility transistor (HEMT) devices generally show a bell-shaped g m curve characteristic much like other FET devices. In this study, we examine g m behavior and conclude that the bell-shaped g m is caused by: (1) devices operating in the linear region, generally under low to moderate V ds bias, (2) nonlinear source and drain resistances, and (3) self-heating thermal effects. When I ds no longer follows a linear increase with V gs due to these three causes, g m decreases and forms a bell shape. The key to maintain the g m flatness is to reduce both parasitic electrical and thermal resistances. [ABSTRACT FROM AUTHOR]

• 24 new thermochronometric ages from the bend section of the Xianshuihe fault system are reported. • New data indicate migration of the locus of fast exhumation towards the fault zone from ∼ 25 to ∼ 10 Ma. • Oligocene-early Miocene fast exhumation along the fault system resulted from crustal shortening. Large-scale strike-slip faults in the southeastern Tibetan Plateau are considered to have accommodated significant crustal extrusion and deformation during the plateau growth. However, the long-term deformation and exhumation history along the large-scale strike-slip faults is still unclear. Here, we present new thermochronological datasets from the near-field of the bend section of the Xianshuihe fault system, they reveal migration of the loci which show rapid exhumation between ∼ 25 Ma and ∼ 10 Ma towards the fault zone. Our new results clearly show a phase of rapid Oligocene-early Miocene basement exhumation, indicating contemporaneous crustal shortening along the fault. Through synthesizing the evidence of Oligocene-early Miocene fast exhumation along the Xianshuihe fault system, and synchronous deformation along adjacent strike-slip and thrust faults in the region, we propose that the southeastern Tibetan Plateau may have reached a remarkable high-elevation topography during this period. This was accompanied by significant crustal shortening under a contractional regime, with northeastward advance of the eastern Himalayan syntaxis and southeastward crustal extrusion originated from the plateau hinterland. Our findings are generally in agreement with sedimentary records in the marginal sea basins and paleo-altimetry studies. [ABSTRACT FROM AUTHOR]

Studies of supercontinental cycle are mainly concentrated on the assembly, breakup and dispersal of supercontinents, and studies of continental crustal growth largely on the growth and loss (recycling) of the crust. These two problems have long been studied separately from each other. The Paleozoic–Mesozoic granites in the Central Asian Orogenic Belt have commonly positive #x03B5;Nd values, implying large-scale continental crustal growth in the Phanerozoic. They coincided temporally and spatially with the Phanerozoic Pangea supercontinental cycle, and overlapped in space with the P-wave high-V anomalies and calculated positions of subducted slabs for the last 180 Ma, all this suggests that the Phanerozoic Laurasia supercontinental assembly was accompanied by large-scale continental crustal growth in central Asia. Based on these observations, this paper proposes that there may be close and original correlations between a supercontinental cycle, continental crustal growth and catastrophic slab avalanches in the mantle. In this model we suggest that rapid continental crustal growth occurred during supercontinent assembly, whereas during supercontinental breakup and dispersal new additions of the crust were balanced by losses, resulting in a steady state system. Supercontinental cycle and continental crustal growth are both governed by changing patterns of mantle convection. [Copyright &y& Elsevier]