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This research established a systematic method to generate various pore-size distributions (PSDs) and studied the effect of PSDs on the shock compaction response of granular materials using two-dimensional mesoscale simulations under identical porosity. Simulations utilized various PSDs for three particle shapes (circle, ellipse, and square). Contacting particle configurations using three PSDs, characterized by spatially uniform distributed pores to heterogeneous distributed pores, and non-contacting particle configurations under a single case of PSD were tested. The PSD of generated particle sets was characterized using coordination number, mean diameter, and bimodality coefficient as statistical metrics. Mesoscale simulations showed that regardless of the conditions of pore distributions, shock compaction of granular materials consistently demonstrates a precursor, shock compaction front, and end. However, the shock compaction velocity of contacting particles was dependent on the PSDs despite the constant initial porosity. The compaction velocity was faster in particle configurations with relatively uniform pore distributions than in heterogeneous pore distributions, which our study demonstrated can be attributed to particle rearrangement during compaction. Circular-shaped particles had high sensitivity in shock compaction response to the various PSDs. Furthermore, a contacting particle configuration tended to propagate the shock compaction wave relatively faster than particles that were in a non-contact configuration. This study established the relative importance of considering PSD as a metric over the coordination number in studies of the shock compaction response of granular materials. Further, insights are provided on the evolving shock substructure to characterize the shock compaction response of granular materials. [ABSTRACT FROM AUTHOR]

A new microwave metamaterial microstrip line (meta-MSL) is studied by integrating planar mushroom metamaterial structures into a conventional MSL. The meta-MSL is featured with an enhanced effective refractive index than the conventional, extracted from numerical demonstrations using the S-parameter method. The extraordinarily increased refractive index is found to be associated with weak dispersion and low dissipation loss, making the meta-MSL particularly beneficial to compact a microwave Wilkinson power divider (WPD). One metamaterial WPD (meta-WPD) is built using new meta-MSLs. Full-wave numerical calculations reveal that the new meta-WPD has low insertion losses, low reflections, and high isolations between the output ports, working as a good substitute for the conventional WPD. However, the new meta-WPD is exceptional in its small size, which is particularly useful in mobile and wireless applications where compact microwave components are in critical demand. [ABSTRACT FROM AUTHOR]

Sensitivity in polymer-bonded explosives (PBXs) relies on the presence of defects, such as cracks and voids, which create localized thermal energy, commonly known as hotspots, and initiate reactions through various localization phenomena. Our prior research has explored the use of internal gas pressure induced by thermite ignition to generate localized defects for PBX sensitization. However, further research is required to gain a more comprehensive understanding of the defect generation process resulting from internal gas pressure. This study investigates the process of defect generation in PBXs in response to internally induced gas pressure by applying controlled compressed gas to a fabricated cavity within the materials, simulating the gas pressure emitting from thermite. X-ray micro-computed tomography was employed to visualize the microstructure of the sample before and after gas injection. The experiments reveal the significance of gas pressure, cavity shape, temperature, and specimen compaction pressure in the defect generation. Numerical simulations using Abaqus/Standard were conducted to assess the defect generation in mock PBXs under varying gas pressures, cohesive properties, and binder thicknesses. The simulation results demonstrate the substantial influence of these properties on the ability to generate defects in mock PBXs. This study contributes to a better understanding of the factors influencing defect generation in mock PBXs. This knowledge is crucial for achieving precise control over defect generation, leading to improved ignition and detonation characteristics in PBXs. [ABSTRACT FROM AUTHOR]

The paper presents an analysis of the effect of processing powders with high hydrostatic pressure (HHP) (300, 500, 700 MPa) and stabilized zirconium dioxide (ZrO 2 + 3 mol.% Y 2 O 3 , (YSZ)) doping on the compaction of metastable nanopowders mixture with γ+θ-Al 2 O 3 + n% YSZ (n = 0, 1, 5, 10, 15 wt%) composition during sintering. The behavior of nanopowders at the initial stage of sintering was studied by dilatometry at a constant heating rate of 5 °C/min, in temperature range from 20 °C to 1500 °C. It has been determined that sintering of compacts occurs in two stages: compaction of γ + θ-Al 2 O 3 (Ⅰ-st stage metastable phases), compaction of the stable α-Al 2 O 3 (ⅠⅠ-nd stage), accompanied by inhibition between them. An "effect of mutual protection against crystallization" of powder mixtures was determined using the X-ray diffraction method. This is characteristic of systems obtained by co-precipitation. A connection between the above mentioned inhibition and an increase in the YSZ additive was found. That, also, correlates to the effect of "mutual protection against crystallization" of Al 2 O 3 – YSZ powder mixtures. A study of the mechanisms and activation energies of γ+θ-Al 2 O 3 + n% YSZ systems' (n = 0, 1, 5, 10, 15 wt%) sintering depending on the YSZ additive amount and the HHP value showed that a dopant and pressure increase leads to activation energy decrease of the initial sintering stage, and the prevailing sintering mechanism is volumetric diffusion in corundum grains. Also, the work shows that for γ+θ-Al 2 O 3 + ≥5 wt% YSZ systems, the optimal compaction pressure is HHP ≥500 MPa, which corresponds to the transition of the sintering mechanism from grain-boundary diffusion to volumetric diffusion. [ABSTRACT FROM AUTHOR]

Simultaneous enhancement of free excitons (FEs) emission and self‐trapped excitons (STEs) emission remains greatly challenging because of the radiative pathway competition. Here, a significant fluorescence improvement, associated with the radiative recombination of both FEs and STEs is firstly achieved in an unconventional ACI‐type hybrid perovskite, (ACA)(MA)PbI4 (ACA=acetamidinium) crystals with {PbI6} octahedron units, through hydrostatic pressure processing. Note that (ACA)(MA)PbI4 exhibits a 91.5‐fold emission enhancement and considerable piezochromism from green to red in a mild pressure interval of 1 atm to 2.5 GPa. The substantial distortion of both individual halide octahedron and the Pb−I−Pb angles between two halide octahedra under high pressure indeed determines the pressure‐tuning localized excitons behavior. Upon higher pressure, photocurrent enhancement is also observed, which is attributed to the promoted electronic connectivity in (ACA)(MA)PbI4. The anisotropic compaction reduces the distance between neighboring organic molecules and {PbI6} octahedra, leading to the enhancement of hydrogen bonding interactions. This work not only offers a deep understanding of the structure‐optical relationships of ACI‐type perovskites, but also presents insights into breaking the limits of luminescent efficiency by pressure‐suppressed nonradiative recombination. [ABSTRACT FROM AUTHOR]

AbstractThis study improved the vibratory probe compaction (VPC) technique by combining it with well-point dewatering to address the challenges of treating newly dredged silt ground. Specific methods were presented to determine the operating frequency based on multi-channel analysis of surface waves (MASW) results, as well as the spacing between compaction points derived from vertical vibration velocity measurements. The effects of well-point dewatering were analyzed through field monitoring of groundwater level, pore water pressure, and ground settlement. A comparative evaluation of the reinforcement of the improved and conventional VPC techniques was conducted through in-situ tests. The results indicate that continuous dewatering suppresses the excessive rise of excess pore water pressure during compaction, effectively eliminating equipment tilting and settlement due to sandblasting water, and enhancing construction efficiency by over 40%. The average standard penetration blow count (N63.5) increases from 4.3 to 11.4, the ground bearing capacity reaches 140.8 kPa and the average ground settlement is 42.5 cm. The cone resistance and sleeve resistance also exhibit higher values, and the risk of soil liquefaction is effectively eliminated. The experiments and practices provide some successful experiences for the wider application of this technique in similar newly reclamation grounds. [ABSTRACT FROM AUTHOR]

Anthropogenic pressures are increasing in coastal ecosystems globally, yet identifying robust indicators of change and managing coastal resources can be complicated by phenotypic plasticity and differential life-history responses of key organisms. We illustrate this using biogeochemical and sandprawn (Kraussillichirus kraussi) response metrics along a human recreation gradient (trampling, sandprawn harvesting) in a South African lagoonal ecosystem. Benthic compaction, oxygen depletion and high porewater ammonia concentrations were associated with greatest recreation intensity. Sandprawn abundance was similar across the recreation gradient and body condition was counter-intuitively greater in areas with maximum recreation, but with higher frequencies of embryonic aberrations and arrested development. These findings suggest different vulnerabilities of life-history stages of sandprawns to recreation, with embryonic stages being highly susceptible. We suggest that embryonic aberrations and developmental changes in endobenthic crustaceans may be sensitive bioindicators of recreation-induced changes in sedimentary systems. [ABSTRACT FROM AUTHOR]

Quantifying seedling emergence pressure or forces (soil impedance to seedling) during the process of plant emergence is difficult in a practical setting. In this study, a mechanical seedling testing device was designed and calibrated to measure seedling emergence pressures experienced by conical or spherical mechanical seedling in soil with varying compaction levels. The data were analysed to generate regression models for predicting seedling emergence forces. Results showed a high correlation between the seedling emergence pressure and soil resistance. The resultant regression model produced a coefficient of determination (R2) of 0.99. After incorporating the morphological characteristics of soybean cotyledon and maize coleoptile into the model, the predicted seedling emergence forces increased with the soil compaction level. During the emergence process, average emergence force of the soybean seedlings was 11.8 N for the lowest compaction level and 28.5 N for the highest compaction level, and the corresponding values of the maize seedlings were 0.2 N and 0.6 N. In a non-compacted field plot, maize crop had a 95.4% emergence rate and soybean crop had 97.2%, whereas for a compacted plot, the corresponding emergence rates were decreased to 19.1% and 60.5%. Inferences made from the study provide information on the dynamics of soil-seedling interaction, which have important implications for managing soil compaction in crop production. • A testing device was developed to measure seedling emergence forces. • Regression models were generated from the measurement data. • Models predicted the seedling emergence forces of soybean and maize. • Seedling emergence force increased significantly with increasing soil compaction. [ABSTRACT FROM AUTHOR]

Root piles exhibit favorable bearing characteristics, rendering them suitable for the foundation of offshore wind power facilities to withstand uplift loads. This study compared the uplift load bearing advantages of root piles to those of equal diameter piles in coral sand foundations. Additionally, it analyzed the effects of relative foundation compaction on the uplift load bearing characteristics of root piles. The tests involved comparing root piles and equal diameter piles in coral sand foundations with relative foundation compaction levels of 0.5, 0.6, 0.7, and 0.8. The results indicate that root piles possess a 62.5% higher pullout capacity than equal diameter piles, with only a 10.7% increase in uplift displacement. As relative compaction increases, the pullout ultimate capacity of root piles initially rises rapidly and then levels off, while the corresponding uplift displacement experiences a sharp decline followed by a relatively stable state. With the increase of relative compaction, the location of the maximum attenuation of axial force and the maximum lateral friction resistance in the root region started to move deeper only under larger loads. Both the implementation of root piles and an increase in relative compaction greatly enhance the pile foundation's ability to resist pullout forces and control deformation. [ABSTRACT FROM AUTHOR]

There is few research about the liquid drainage in the sample compaction of asphalt emulsion mixtures (AEMs). In this study, the liquid drainage of AEMs with cement is quantitatively measured. The air voids, indirect tensile strength, and moisture susceptibility of cured samples are investigated to explain the effect of liquid drainage. The test results indicate that the liquid drainage percentages of samples are influenced by emulsion content, cement content, compaction methods, and mold types. Liquid drainage is beneficial in terms of decreasing air voids and improving moisture resistance. However, these positive effects can be negligible when using a perforated mold. The drained liquid consists of free water and a small amount of asphalt droplets. The liquid drainage does not mean that the total air voids in samples are in a water saturation state. The liquid drainage in laboratory compaction cannot reflect the real water movement in construction compaction. [ABSTRACT FROM AUTHOR]

Red mudstone is a problematic soil that is easily subjected to weathering, disintegrating, and swelling. In this study, a series of large-scale cyclic triaxial tests were performed to investigate the cumulative deformation behavior of red mudstone clay mixed with weathered red mudstone gravel as an improved coarse-grained red mudstone soil (IRMS). The influences of compaction moisture content and confining pressure were investigated. The cyclic loading was applied from 25 to 225 kPa with an increment of 25 kPa and 1,000 or 2,000 cycles for each stage at a frequency of 2 Hz. The experimental results indicate that the strains at the onset of failure are approximately 1% for the optimal moisture content (OMC) with the number of cycles N = 14,000–16,000, and the strains are approximately 1% for the moisture content 2% dry of OMC with N = 12,000–14,000, while the strains exceed 10% for the moisture content 2% wet of OMC with N = 3,000–4,000. The cumulative strain decreases with increasing confining pressure from 20 to 50 kPa, but the influence becomes more significant under higher dynamic stress. A prediction model is proposed for the evolution of cumulative strain under cyclic loading. The IRMS could be used as a construction material for railway subgrade with proper control of field compaction moisture content. [ABSTRACT FROM AUTHOR]

To enhance our understanding of soil behavior at critical states, considering that natural soil is composed of granular matter, a quasi-static inertia number taking soil compaction into account is proposed. In analyzing classical triaxial test data of soil, the scaling law of quasi-statically deforming grains at the critical state is explored; a simple linear relationship is found between the coefficient of friction and the proposed number. This scaling law describes quantitatively the influence of initial compaction, shear rate, confining pressure, and particle size on the frictional strength of granular soils when they reach the critical state. The number proposed is employed to describe the scaling of volumetric behavior of granular soils undergoing quasi-static deformation. The difference between the particle volume fraction at the critical state and that at the initial compacted state is also found to be linearly correlated with the quasi-static inertia number, for soil at the critical state. [ABSTRACT FROM AUTHOR]

Aggregates consisting of submicron-sized cohesive dust grains are ubiquitous, and understanding the collisional behavior of dust aggregates is essential. It is known that low-speed collisions of dust aggregates result in either sticking or bouncing, and local and permanent compaction occurs near the contact area upon collision. In this study, we perform numerical simulations of collisions between two aggregates and investigate their compressive behavior. We find that the maximum compression length is proportional to the radius of aggregates and increases with the collision velocity. We also reveal that a theoretical model of contact between two elastoplastic spheres successfully reproduces the size- and velocity-dependence of the maximum compression length observed in our numerical simulations. Our findings on the plastic deformation of aggregates during collisional compression provide a clue to understanding the collisional growth process of aggregates. [ABSTRACT FROM AUTHOR]

Thermal energy storage (TES) systems have been proven in their capacity as a crucial component of energy grids relying on renewable sources. An established sensible heat storage technology is a packed-bed TES, employing a granular filling material as a heat storage medium, which is subjected to repeated heating-cooling cycles. As a result of the recurring particle expansion and contraction, excessive stresses and strains can develop and cause material damage. This leads to the increasing need for reliable numerical tools in order to improve the TES design and increase their durability. For this purpose, we propose a continuous thermo-mechanical approach, within the framework of the theory of hypoplasticity, that can accurately predict the single as well as cyclic loading behavior of the filling material. This work focuses on the stress–strain relations and compaction mechanisms of the granular bed in contact with a storage wall with variable inclination and friction coefficient. Furthermore, the important aspect of the wall expansion under the temperature change is also taken into account as well as the specific case when the wall expands more than the granular material. By conducting comprehensive simulations, we demonstrate that our novel numerical model adheres to existing experimental investigations and mitigates shortcomings in the predictive capabilities of previous continuous approaches. [ABSTRACT FROM AUTHOR]

The compaction of hydrogel films under permeation flow can be measured, in-situ, by tracking the internal displacements of their structure, thereby revealing the internal deformation profile. Additionally, monitoring the permeation flow rate and applied pressure over time enables determination of variations in the hydrogel's permeability due to flow-induced compaction. Hydrogels are soft porous materials capable of containing high amounts of water within their polymeric matrix. Flow-induced internal deformation can modify the hydrogel's permeability and selectivity, which are important attributes in separation processes, both industrial (e.g., membrane-based water purification) and natural (mucous filters in suspension feeders and intestinal lining) systems. Measuring the flow-induced compaction in thin hydrogels films can reveal the interplay between flow and permeability. However, the micro-scale internal compaction remains uncharted for due to experimental challenges. A technique is demonstrated for analyzing the compaction and stratification of permeable soft materials, in-situ, created by a pressure-driven permeation flow. To this end, the internal deformations within a soft material layer are calculated, based on tracking the positions of fluorescent micro-tracers that are embedded within the soft material. We showcase the capabilities of this technique by examining a hundred-micron-thick calcium-alginate cake deposited on a nanofiltration membrane, emphasizing the achieved micro-scale resolution of the local compaction measurements. The results highlight the possibility to examine thin hydrogel films and their internal deformation produced by flow-induced stresses when varying the flow conditions. The method enables the simultaneous calculation of the soft material's permeance, as the pressure-driven flow conditions are continuously monitored. In summary, the proposed method provides a powerful tool for characterizing the behaviour of permeable soft materials under permeation conditions, with potential applications in engineering, biophysics and material science. [ABSTRACT FROM AUTHOR]

Certain data compression techniques like pruning leads to unstructured sparse Convolution Neural Network (CNN) models without directly leveraging sparsity in optimizing both memory consumption and inference latency of a model having low to medium sparsity. State-of-the-art storage techniques either optimize model size at the cost of execution latency or optimize inference latency at the overhead of the memory consumption of the model. This tradeoff is largely due to the absence of storage selection methodology addressing sparsity sensitivity, arising from varied sparsity and positions of nonzero values called sparsity structure across different sparse layers of a model. However, this issue remains unexplored due to the lack of support to handle sparse data in the current deployment standards for edge devices. This article introduces a data compaction strategy for unstructured sparse data that not only compresses nonzero data but also encodes it, leveraging the memory consumption and latency reduction benefits of both data compression and data encoding techniques. We propose a novel storage representation, named Encoded Partitioned Hybrid Sparse (EPaHS) format, which addresses sparsity sensitivity by customizing data storage based on the sparsity structure of the data. Our data compaction technique and storage solution optimizes the tradeoff between the memory consumption and inference latency of a sparse model without altering the network architecture and affecting its accuracy. Our solution easily extends to higher-dimensional data and outperforms standard storage solutions. It proves to be beneficial to all the valid mode orientations of multi-dimensional data. For an important health and wellness application, a single-lead short-time ECG classification model, EPaHS achieves up to \({\tt 16.18\%}\) reduction in size and \({\tt 15.16\%}\) reduction in latency when compared to its original model of \({\tt 42}\) MB size and \({\tt 26.35}\) sec latency, having \({\tt \approx 59\%}\) sparsity. For a ResNet50 model handling higher-dimensional data, it achieves \({\tt 21.33\%}\) size reduction and \({\tt 53.9\%}\) latency gain against the original model of \({\tt 3265}\) KB size and \({\tt 1.7}\) sec latency, having \({\tt \approx 67\%}\) sparsity. [ABSTRACT FROM AUTHOR]

LSM-tree-based key-value stores (KV stores) convert random-write requests to sequence-write ones to achieve high I/O performance. Meanwhile, compaction operations in KV stores update SSTables in forms of reorganizing low-level data components to high-level ones, thereby guaranteeing an orderly data layout in each component. Repeated writes caused by compaction (a.k.a. write amplification) impacts I/O bandwidth and overall system performance. Near-data processing (NDP) is one of the effective approaches to addressing this write-amplification issue. Most NDP-based techniques adopt synchronous parallel schemes to perform a compaction task on both the host and its NDP-enabled device. In synchronous parallel compaction schemes, the execution time of compaction is determined by a subsystem that has lower compaction performance coupled by under-utilized computing resources in a NDP framework. To solve this problem, we propose an asynchronous parallel scheme named PStore to improve the compaction performance in KV stores. In PStore, we designed a multi-tasks queue and three priority-based scheduling methods. PStore elects proper compaction tasks to be offloaded in host- and device-side compaction modules. Our proposed cross-leveled compaction mechanism mitigates write amplification induced by asynchronous compaction. PStore featured with the asynchronous compaction mechanism fully utilizes computing resources in both host- and device-side subsystems. Compared with the two popular synchronous compaction modes based on KV stores (TStore and LevelDB), our PStore immensely improves the throughput by up to a factor of 14 and 10.52 with an average of a factor of 2.09 and 1.73, respectively. [ABSTRACT FROM AUTHOR]

This study is a critical review of municipal solid waste (MSW) hydraulic conductivity that includes investigation of the influence of vertical stress, dry unit weight and degradation. A total of 56 studies were compiled that included laboratory-, pilot- and landfill-scale hydraulic conductivity experiments. Compacting waste and increasing vertical stress reduce MSW hydraulic conductivity via reshaping the pore networks throughout the waste matrix, reducing the void ratio and increasing tortuosity. However, the magnitude of reduction in hydraulic conductivity is dependent on stress, waste composition and decomposition. Solid waste decomposition can have opposing effects on hydraulic conductivity. Some studies have indicated that an increase in MSW decomposition results in particle size reduction and settlement that reduces the void ratio and decreases hydraulic conductivity. Conversely, some studies indicate that waste decomposition reduces the solid mass, which increases the void ratio and creates larger flow paths that increase hydraulic conductivity. The data compilation, observations and key findings from this study are beneficial for solid waste practitioners to improve design, analysis and operation of MSW landfills. [ABSTRACT FROM AUTHOR]

In this study, a three‐dimensional large‐scale numerical model is established to investigate the failure characteristics of overlying strata and mechanism of strong ground pressure induced by excavation disturbance from multiple working faces. The characteristics of overlying strata fractures, heights of the caving zone and the fracture zone, and evolution of the stress field are systematically analyzed. The numerical simulation results reveal that the height of the caving zone after mining is 8.1 m, and that of the fracture zone is 27.3 m under the conditions of gently inclined thin coal seams. These findings are consistent with the theoretical results. The fracture development process can be divided into three stages: extensive development of new fractures, partial compaction of fractures, and closure of numerous fractures. In the structure of the post‐mining overlying rock, four stress zones are identified as follows: two zones of stress concentration at both ends of the working face, respectively, a zone of relatively high stress at the middle of the working face with low overlying strata, and a zone of stress fully released at the middle of the working face with high overlying strata. Comprehensive analysis of the maximum vertical stress of the cross section and the stress of the working face indicates that the stress increases significantly when mining enters the gob square stage and the roof does not collapse timely. [ABSTRACT FROM AUTHOR]

Sulfate dry-wet cycle erosion significantly affects the mechanical properties of concrete. Investigating the uniaxial compressive stress-strain relationship under these conditions is essential for developing accurate constitutive models. This study analyzes the uniaxial stress-strain curves of concrete subjected to dry-wet cycles in 5% and 15% sulfate solutions. The results show that the initial compaction phase in the stress-strain relationship is particularly pronounced under increasing sulfate concentrations and cycle counts. The concrete experiences an extended compaction phase, which accounts for up to 35.71% of the total strain process. This finding challenge traditional constitutive models, which struggle to accurately describe this phase. To address this issue, the study develops a nonlinear stress-strain model for concrete, incorporating the initial damage caused by sulfate dry-wet cycle erosion, based on Weibull statistical damage mechanics principles. The research indicates that the effects of sulfate concentration and cycle count are predominantly reflected in the pronounced nonlinearity of the skeleton strain function's opening size (a) and shape characteristics (b), modeled using a fourth-degree polynomial. The model demonstrates an excellent fit to experimental data with an R2 value of 0.99989, showing that the proposed nonlinear stress-strain relationship effectively captures the uniaxial mechanical behavior of concrete under sulfate dry-wet cycle erosion and provides a robust framework for developing constitutive models in such environments. [ABSTRACT FROM AUTHOR]

In this paper, we study strong Kähler with torsion (SKT) and generalized Kähler structures on solvable Lie algebras with (not necessarily abelian) codimension 2 nilradical. We treat separately the case of J$J$‐invariant nilradical and non‐J$J$‐invariant nilradical. A classification of such SKT Lie algebras in dimension 6 is provided. In particular, we give a general construction to extend SKT nilpotent Lie algebras to SKT solvable Lie algebras of higher dimension, and we construct new examples of SKT and generalized Kähler compact solvmanifolds. [ABSTRACT FROM AUTHOR]

The distributary channels in shallow‐water delta are well‐developed in tight sandstone. There are few studies on the channel type and diagenetic differences among them. To illustrate the relationship between channel types and high‐quality reservoirs, this study summarizes the lithofacies types and sequences in the second member of the Xujiahe Formation. We use core data, outcrops, and modern sediments observation, scanning energy spectrum, and rock thin sections. The lithofacies can be divided into 15 types, and there are four types of vertical lithofacies sequence. Lithofacies sequences are different in lithofacies, channel scale, reservoir porosity and permeability, and so forth. They are formed in various hydrodynamic environments. With the continuous bifurcation of the channels, the width and depth of the channels are decreasing, forming different lithofacies sequences. Four types of distributary channels are classified. The characteristics of these channels are described, and the sedimentary models are established. Distributary channel types are related to the diagenetic process. Channel type I and the bottom of type II develop moderate compaction–dissolution diagenetic facies, the middle and upper parts of type II and type III can develop strong compaction, moderate compaction–dissolution, or strong cementation diagenetic facies, and type IV can develop strong compaction diagenetic facies. High‐quality reservoirs are developed in limitedly distributed in distributary channels of type I and type II, and part of type III. This study provides a useful view for evaluating high‐quality reservoirs based on distributary channel types. [ABSTRACT FROM AUTHOR]

Assessing the compaction quality of rockfill materials is an essential link in the runway construction. However, traditional on-site limited sampling detection is not only time-consuming and labour-intensive, but also destructive. Common ground penetrating radar (GPR) calculates the relative permittivity of a material by measuring its thickness. Nonetheless, assessing the thickness of runway construction materials poses a significant challenge. To address this challenge, this paper focuses on the Hilbert -Huang transform (HHT) analysis of GPR signal of different compacting materials, and then replaces the traditional method of calculating the relative permittivity by measuring the thickness of materials. At the same time, taking the runway as an example, this work verified a crest factor (CF) index effectiveness in predicting the relative compaction of rockfill material through HHT analysis of GPR signals collected in the field, with an average error rate of 4.03%. Finally, Kriging interpolation method is used to estimate the compaction quality of any point, and the corresponding heat map of compaction quality evaluation is generated to determine the area of insufficient compaction in the construction process. Highlights The GPR method is used for non-destructive testing of the compaction quality of runway rockfill materials; Compaction quality evaluation by multiple indicators of GPR data signal processing. The influence of number of roller passes, materials mix ratios and different rockfill materials on the compaction quality of runway are analysed. The applicability of the GPR method is verified by runway construction tests. [ABSTRACT FROM AUTHOR]

Successful management of chalk reservoirs for various subsurface applications as well as construction in chalk/limestone formations rely on descriptions of compaction behaviour commonly predicted from laboratory experiments. This study aims to understand and describe better the compaction behaviour that oil and water-saturated chalk undergo. Seven North Sea Lower Cretaceous chalk samples with initial porosity ranging from 31 to 45% were compacted hydrostatically in the laboratory. The traditionally named elastic, transitional, elastoplastic and strain hardening phases were identified from stress–strain curves. The observed compaction behaviour is described in phenomenological terms based on the interpretation of Biot's coefficient as a measure of grain-to-grain contact area within the chalk frame. Biot's coefficient was derived from elastic wave velocities and bulk density via Gassmann fluid substitution by first approximations assuming a simple calcite-bearing rock frame. Biot's coefficient identifies both elastoplastic and elastic phases in the initial compaction phase traditionally denoted as the elastic phase. The plastic component of the elastoplastic phase presumably originates from closure of micro-crack introduced by unloading and equilibration from core recovery. Biot's coefficient is a reliable indicator of pore collapse, and a specific constant magnitude of purely elastic strain controls the onset of pore collapse. In situ reservoirs presumably only experience the elastic strain during effective stress changes, not the elastoplastic behaviour seen in experiments. Yet, as laboratory experiments often form a calibration background for large-scale models, quantifying the plastic component of elastoplastic phases and pore collapse from pure elastic strain provides new insight to improve models and avoid the unphysical use of porosity as a controlling physical parameter. Highlights: During initial compaction, both elastoplastic and elastic phases exit and are identified from Biot's coefficient. During compaction, a local minimum Biot's coefficient derive from ultrasonic velocities is a reliable indicator of pore collapse. A critical and purely elastic strain derived from applied stress and dynamic moduli is the controlling mechanism of pore collapse. Identification of subphases and a critical pore collapse elastic strain provides new insight into calibration of reservoir model from experiments. [ABSTRACT FROM AUTHOR]

Deep-core samples collected from the southeastern shelf (Korea Strait) of Korea were used to characterize physical properties of the area with respect to burial depth. Laboratory analyses of the acoustic and physical properties of the samples were conducted and shear-wave velocity, velocity ratio, and Poisson's ratio were calculated. Geoacoustic and physical property data at the two sites were in correlation with the lithological units alternating between sandy mud and muddy sand at sedimentary depth. Geoacoustic units (GAUs) identified from sites 19ESDP-104 and 21ESDP-203 were divided into 6 and 15 units with sedimentary depth, respectively, and geoacoustic models were developed for the sedimentary layers around these sites. This suggests that the physical properties are not only controlled by lithology and compaction caused by dewatering with burial depth but also by different sedimentary environments after deposition. Based on the velocity ratio and velocity anisotropy (particularly at site 21ESDP-203), clay particles within the sediment layers had a greater effect on compaction owing to the overburden pressure with burial depth. [ABSTRACT FROM AUTHOR]

The influence of the microstructure of highly confined secondary explosive on the transition to detonation initiated by a thermal solicitation was studied. Three batches of HMX with three orders of magnitude in the granulometry were characterized and compacted in brass tubes to determine their CoDDT distance following a LASER pulse initiation. The post-compaction granulometry was less relevant than the pellets' pore size and the batch initial granulometry which were determinant. A pore size below 200 nm was not sufficient for a transition. The run length was scaled with the inner diameter for porosities higher than 15% for the big grains. [ABSTRACT FROM AUTHOR]

While the 'compact city' can provide environmental benefits, densification can result in negative trade-offs at the local scale – e.g. through increases in density and the removal of urban green space – and densification projects are often rejected by locals. This paper explores examples of densification in a compact European city, integrating different stakeholder perspectives from planners as well as neighbours of densification projects. Neighbours do not reject densification per se, but evaluate the individual projects and their contexts. Evaluation depended mostly on how the projects impacted urban green space, social mix and available parking spaces. Implications are discussed and 'good practice' criteria that could reduce the trade-offs of densification are suggested. [ABSTRACT FROM AUTHOR]

This paper examines the dynamic evolution of the compact three-planet system Kepler-51. Possible resonant states of the system are analyzed and a search for potential chains of mean motion resonances is carried out. Using the Posidonius software package the dynamic evolution of the system is studied over a time interval of 100 Myr, taking into account tidal interaction. Also, for various initial values of eccentricities, inclinations, arguments of periapsis and longitudes of the ascending nodes of orbits, modeling of the dynamic evolution of the planetary system is carried out within the framework of the semi-analytical theory of motion. It is shown that the compact planetary system Kepler-51 is not resonant. Under initial conditions corresponding to the masses and elements of the planets' orbits, determined from observations taking into account their errors, the evolution of the system is stable and regular over the studied interval of 100 Myr. [ABSTRACT FROM AUTHOR]

To investigate the installation damage of geogrids during roller compaction under rockfill condition, a three-dimensional discrete element model for roller compaction of geogrid-reinforced rockfill was established. The rockfill was modeled by irregular rigid block elements, while the geogrids were modeled by bonding basic ball elements. The model parameters were then calibrated by triaxial consolidated-drained and tensile tests. The displacements of the geogrids in three perpendicular directions, and the strength of the geogrids was analyzed. Additionally, the effects of compaction parameters on the installation damage of the geogrids were studied. The results showed that deformation of the geogrids was relatively small in the roller-driving direction but significant in the roller-axis and settlement directions. The damage modes of the geogrids could be mainly classified into three types: rib fracture, rib end fracture, and node fracture. The installation damage of the geogrid was derived mainly from its uneven deformation and fracture, and after roller compaction the strength distributions at different locations of the geogrid layer showed a normal distribution. Furthermore, the installation damage of the geogrids increased with increasing excitation force and compaction passes but decreased with increasing overlying rockfill thickness, roller velocity, and excitation frequency. • The installation damage of the geogrids was studied by the discrete element method. • The deformation and strength of the geogrids were analyzed. • The effects of compaction parameters were also investigated. [ABSTRACT FROM AUTHOR]

Compaction is a critical step in the construction of an asphalt mixture. To effectively compact an asphalt mixture, the locking point, which identifies the effective compaction, was introduced based on the change in volumes of the asphalt mixture during gyratory compaction. However, the existing definition of the locking point is solely dependent on the volumetric properties of compacted mixtures and may not be necessarily associated with the skeleton of the mixture. In this paper, the locking point for a compacted asphalt mixture was defined and determined using dynamic responses measured by a particle sensor. Gyratory compaction and field compaction tests were carried out with particle sensors embedded to analyze the evolution of the aggregates' dynamic responses. Then, a novel dynamic response rate of the change index Rs was proposed to represent the evolution process of the asphalt mixture compaction. The Superpave gyratory compactor (SGC) results show that the acceleration and rotation angle of the particle sensors varied during compaction and did not converge in the end. The SGC compaction process can be divided into three stages: the initial compaction stage, transition stage, and plateau stage based on the rate of stress (Rs). Meanwhile, the inflection point between the transition stage and plateau stage in the compaction curve was defined as the locking point. It was found that the locking point determined by the sensors in the middle of the compacted specimens was later than that determined by the gyratory compaction. The contact interlocking initiated at the bottom of a compacted specimen and moved upward. The field compaction test results of the particle sensors showed that the contact stress also had a significant trend of convergence after being compacted by a pneumatic-tired roller, which indicates that the test stress index based on the particle sensors could be used for the evaluation of compaction quality. [ABSTRACT FROM AUTHOR]

Large-scale triaxial tests are popular for evaluating the mechanical properties of railroad ballast. The literature shows that different compaction methods have been used to prepare the samples. This research investigates the potential variation caused by different compaction methods, even when the samples are compacted to the same density. A series of triaxial tests are conducted, and the results confirm that the way in which ballast is compacted significantly affects its stiffness, but not its peak strength, as long as the density is consistent. Discrete-element method simulations are performed to explore this phenomenon and discover that stiffness variations are caused by different ways in which particles interlock and arrange themselves during compaction. Based on the findings from this study, it is recommended to consider the influence of compaction methods when conducting large-scale triaxial testing on railroad ballast or when evaluating the test results. [ABSTRACT FROM AUTHOR]

Water-bearing fractured rock masses are prone to geological hazards due to freeze–thaw (FT) damage, which brings adverse effects on the stability of rock engineering. In order to study the FT damage characteristics of rocks, the intact and pre-cracked cyan sandstone samples were taken as the research objects, with pre-crack inclination angles β of 0°, 45°, and 90°, respectively. The effects of FT cycle on stress–strain curve, peak strength, apparent stiffness and FT coefficient of cyan sandstone samples were studied by uniaxial compression test. Based on macroscopic damage variables, a damage constitutive model of cyan sandstone is proposed combined with strain equivalence hypothesis and Weibull distribution hypothesis. Considering that the strain equivalence hypothesis is difficult to reflect the compaction effect of microcracks, the damage constitutive equation is modified by taking the ratio of the secant modulus of the actual stress–strain curve to that of the classical Lemaitre damage constitutive curve as the correction coefficient. The application results show that the modified constitutive model can well describe the stress–strain relationship of cyan sandstone before the peak strength, which verifies the reliability of the model parameters derived from the test data, and the practicability of the damage characterization method and correction coefficient. The results can provide theoretical reference for the study of FT damage of rocks in cold regions. [ABSTRACT FROM AUTHOR]

Calender process is important to improve the mechanical and electrochemical properties of cathode materials. To explore pressure effect on structure and resistance of electrode powder, the morphology and surface area of lithium cobalt oxide (LCO) powder under different pressure are investigated. Meanwhile, the real‐time stress, density, and conductivity of LCO powder upon compaction are tested by a self‐made detection system. Moreover, the battery performance of LCO powder after compaction is compared in coin cells. This work elucidates the relationship between compaction density, powder resistance, and electrochemical performance of cathode materials for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

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Roller-Compacted Concrete Pavements (RCCP) display a combination of attributes associated with both asphalt and conventional rigid pavements. However, their broader implementation remains constrained. One of the reasons is the discrepancy between the manner in which the RCCP mixture behaves in a laboratory setting and its performance in the field. In laboratory settings, the RCCP is blended in accordance with the modified Proctor approach. Subsequently, the Vibratory Hammer (VH) technique is employed to create specimens for strength characterization. In contrast, the actual pavement is constructed using a variety of rollers, including static, pneumatic, and vibratory types. Additionally, specimens are extracted from the actual pavements and compared to laboratory values to ensure quality control. The usage of diverse compaction mechanisms and energies throughout these procedures gives rise to discrepancies between field and laboratory behavior, necessitating a comprehensive understanding. This investigation examines the various techniques for designing RCCP, including the VH, Vibratory Table (VT), and Manufactured Roller (MR), which have been developed and utilized by previous researchers. These techniques are then compared to Field Specimens (FS). Furthermore, the RCCP is treated with three distinct curing methods: normal curing, coating the mixture with waterproof material, and spraying with water. The compressive strength of the RCCP has been sensitive to both the compaction method employed and the curing process. Additionally, research has indicated that the MR technique may be a viable option for the RCCP design. However, it is essential to optimize this technique to ensure an accurate simulation of the field conditions. [ABSTRACT FROM AUTHOR]

Several research works have been carried out to improve cold mix asphalt (CMA), being an eco-friendly construction; however, very few attempts have been made on curing of loose CMA mixture before the compaction process for preparing the specimens that simulate the actual field condition. The present study aims to assess the effect of various curing parameters (curing temperature, curing duration and curing condition) on loose CMA mixture for improvement in the curing rate and strength of compacted samples. The curing rate of the loose mixture was satisfactory in the temperature range of 40–60°C; however, curing in the oven at 50°C closely simulated the local field condition in normal weather. After investigating different processes for effective curing of the loose mix, the protocol with initial 1% moisture loss in the air at room temperature, followed by 3% moisture loss in the oven at 50°C resulted in the optimum CMA properties. [ABSTRACT FROM AUTHOR]

Highly porous titanium foams are great candidates for replacing bone structures with a low elastic modulus owing to their ability to avoid the stress shielding effect. However, the production of highly porous foams (>70 vol.%) with well-distributed, stable, and predictable porous architectures using powder compaction and space holders is challenging. In this study, pure titanium powder and mechanically alloyed Ti-13Ta-6Sn were mixed with 50, 70, and 80 vol.% KCl powders as a space holder, cold-compacted, and sintered in a plasma-assisted sintering reactor to produce highly porous foams. The space holder was completely removed using heat and plasma species collisions prior to sintering. A Ti-13Ta-6Sn alloy powder with α, β, and metastable FCC-γ phases was synthesized. The characteristics of the alloyed powder, mixing step, and the resulting sintered samples were compared to those of CP-Ti. After sintering, the alloy exhibited α and β phases and a reduced elastic modulus. Foams with an elastic modulus in the range of the cortical and trabecular bones were obtained. The results showed the effects of the space holder volume fractions on the volume fraction, size, distribution, interconnectivity, and shape of the pores. The Ti-13Ta-6Sn foams exhibited a uniform open-celled porous architecture, lower elastic modulus, higher yield strength, and higher passivation resistance than CP-Ti. Ti-13Ta-6Sn exhibited a nontoxic effect for the mouse fibroblast cell line. [ABSTRACT FROM AUTHOR]

In recent years, smart aggregates have emerged as a promising tool for monitoring the movement of and changes in particles inside asphalt mixtures. However, there remain significant differences between smart aggregates and real rock aggregates, particularly the lack of an asphalt coating on the surface of smart aggregates. Currently, the research on the impact of smart aggregates themselves on the structure and properties of asphalt mixtures is lacking. Therefore, this study focuses on the influence of smart aggregate size on the mesostructure and mechanical properties of asphalt mixtures. Firstly, based on laboratory tests and the discrete element method (DEM), discrete element models of asphalt mixture specimens containing smart aggregates of various sizes were constructed, followed by simulated compaction tests. The effects of smart aggregate size on the mesostructure of asphalt mixture voids were then analyzed. Lastly, in this study, the changes in the dynamic modulus of asphalt mixtures were explored with increasing smart aggregate size and the underlying mechanisms. The results indicate that as the size of smart aggregates increases, the average void ratio of the asphalt mixture specimens decreases, but the heterogeneity of the void distribution increases. Additionally, with the increase in smart aggregate size, the dynamic modulus of the mixture specimens decreases. Further strain analysis of the specimens suggests that the increase in cross-sectional deformation is the primary cause of the reduction in modulus. [ABSTRACT FROM AUTHOR]

Data-structure dynamization is a general approach for making static data structures dynamic. It is used extensively in geometric settings and in the guise of so-called merge (or compaction) policies in big-data databases such as LevelDB and Google Bigtable. Previous theoretical work is based on worst-case analyses for uniform inputs—insertions of one item at a time and non-varying read rate. In practice, merge policies must not only handle batch insertions and varying read/write ratios, they can take advantage of such non-uniformity to reduce cost on a per-input basis. To model this, we initiate the study of data-structure dynamization through the lens of competitive analysis via two new online set-cover problems. For each, the input is a sequence of disjoint sets of weighted items. The sets are revealed one at a time. The algorithm must respond to each with a set cover that covers all items revealed so far. It obtains the cover incrementally from the previous cover by adding one or more sets and optionally removing existing sets. For each new set the algorithm incurs build cost equal to the weight of the items in the set. In the first problem the objective is to minimize total build cost plus total query cost, where the algorithm incurs a query cost at each time \(t\) equal to the current cover size. In the second problem, the objective is to minimize the build cost while keeping the query cost from exceeding \(k\) (a given parameter) at any time. We give deterministic online algorithms for both variants, with competitive ratios of \(\Theta(\log^{*}n)\) and \(k\) , respectively. The latter ratio is optimal for the second variant. [ABSTRACT FROM AUTHOR]

Flax reinforced composites are becoming popular in automotive and civil industries due to their green production and recycling, and for good specific strength. To manufacture composites, firstly a multi-layer of flax preforms undergo compressive pressure before resin impregnation that causes nesting, wherein, fibres of one layer fit into the adjacent layers. This debulking of the preforms under compression is an important feature that determines the fibre volume fraction of composites. In this study, four flax structures such as: nonwoven tapes, unidirectional fabric, hopsack fabric, and nonwoven tape with glass veils were investigated for compaction behaviour under pressures between 1 and 10 bars, in single and multi-layer states, in dry and wet states, under different loading cycles, and in different ply orientations (0°/0° and 0°/90°). Nesting has been calculated for single- and multi-layer stacks. It was observed that the nonwoven structures shown greater thickness reduction compared to woven structures. Nesting factor was found to be higher than 1 for the nonwoven structures under compaction, indicating lower nesting, compared to the woven structures. In terms of thickness under repeated compaction, the reduction was the highest during first compressions, compared to the 2nd and 3rd compressions, for all the structures. When wettability was examined, thickness reduction for wet plies was higher for all the structures, compared to the dry phase. Finally, a comparative study was shown to evaluate fibre volume fractions of the composites. [ABSTRACT FROM AUTHOR]

Intelligent compaction, particularly fully autonomous compaction, has emerged as a widely accepted innovative technology for enhancing compaction quality and efficiency. When multiple rollers are concurrently engaged in compaction within the same region, the trajectory planning for each roller and cooperative control become pivotal factors in ensuring efficient and safe compaction. This paper presents a comprehensive methodology framework for achieving safe and efficient cooperative operations in multi‐roller automation application. Initially, conventional rollers are retrofitted with autonomous functionality, allowing them to automatically follow preset trajectories through a tracking control algorithm. A trajectory planning method is then proposed, tailored for multi‐roller operations. Subsequently, a series of cooperative control strategies are outlined to determine the optimal timing for executing compaction tasks. Additionally, a cooperative control strategy is proposed for multi‐roller operations, known as “move forward and backward together” control, which ensures the rollers initiate and cease movement without colliding. Finally, the proposed trajectory planning method and cooperative control strategies are validated through field tests conducted on a 100‐m‐long, 12‐m‐wide compaction test site. These tests include single‐roller trials, two‐roller‐in‐a‐row experiments, and multi‐roller cooperation tests. The average trajectory tracking error is maintained below 15 cm, and the effectiveness of the control strategies is demonstrated. [ABSTRACT FROM AUTHOR]

Carbon nanotube fibers (CNTFs) are considered an ideal candidate as next‐generation conducting wires due to their high conductivity and low density. However, the orientation and compaction of the nanotubes in a CNTF need to be further improved to achieve even higher conductivity and ampacity. Here the fabrication of double‐wall CNTFs (DWCNTFs) is reported by a dry‐jet wet spinning method, which significantly improves the orientation and compaction of the carbon nanotubes (CNTs). As a result, the obtained DWCNTFs have a record high electrical conductivity of 1.1 × 107 S m−1 and ampacity of 8.0 × 108 A m−2. The fibers also have a high tensile strength of 1.65 GPa and a toughness of 130.9 MJ m−3, among the highest for wet‐spun CNTFs. The DWCNTFs preserve their integrity and conductivity after more than 5000 bending cycles. Theoretical calculations indicate that in a dry‐jet wet‐spinning process, gravity promotes the orientation of the CNTs along the axial direction of the fiber. [ABSTRACT FROM AUTHOR]

For different applications, various handcrafted descriptors are reported in the literature. Their results are satisfactory concerning the application they were proposed. Furthermore in the literature, the comparative study discusses these handcrafted descriptors. The main drawback which was noticed in these studies is the restriction of implementation only to single application. This work fills this gap and provides the comparative study of 10 handcrafted for two different applications and these are face recognition (FR) and palmprint recognition (PR). The 10 handcrafted descriptors which are analyzed are local binary pattern (LBP), horizontal elliptical LBP (HELBP), VELBP, robust LBP (RLBP), local phase quantization (LPQ), multiscale block zigzag LBP (MB-ZZLBP), neighborhood mean LBP (NM-LBP), directional threshold LBP (DT-LBP), median robust extended LBP based on neighborhood intensity (MRELBP-NI) and radial difference LBP (RD-LBP). The global feature extraction is performed for all 10 descriptors. PCA and SVMs are used for compaction and matching. Results are done on ORL, GT, IITD-TP and TP. The first two are face datasets and the latter two are palmprint datasets. In face datasets, the descriptor which attains the best recognition accuracy is DT-LBP and in palmprint datasets, it is MB-ZZLBP which surpass the accuracy of the other compared methods. [ABSTRACT FROM AUTHOR]

Glass frits effectively facilitate the sintering densification to produce high-density terminal electrodes, crucial for achieving high reliability of MLCC (Multilayer Ceramic Capacitors) devices. However, manufacturing terminal electrodes with high density and strong adhesion under low-temperature sintering condition still has enormous challenges. Herein, Na 2 O–BaO–ZnO–B 2 O 3 –SiO 2 glass has been fabricated for low temperature sintering copper paste. We demonstrate that the densification degree and adhesion strength of the terminal electrode can be notably optimized by adjusting the Na 2 O content in the glass frit. The doping of Na+ in glass effectively improves the wettability of the melt on the copper substrate and the surface tension of the glass melt, enhancing the capillary force in the liquid phase sintering process. The rate of electrode densification is accelerated by the increase in capillary force, thus reducing the sheet resistance of copper film from 4.52 to 4.30 mΩ/□. Furthermore, with the increase in the Na+ content, the work of adhesion between glass and ceramic gradually increases, which effectively enhances the shear strength of the electrode from 19.66 MPa to 29.55 MPa. Our work provides novel insights for the design of glass compositions in the field of terminal paste. [ABSTRACT FROM AUTHOR]

In offshore pile engineering, the installation of jacked piles generates compaction effects within soil, thus further affecting previously installed adjacent piles. This study proposes a three-dimensional numerical model for pile group installation, soil consolidation, and loading analysis. Subsequently, the effect of pile spacing and pile length-to-diameter ratio on the deformation, internal forces, and vertical bearing capacity of adjacent piles are investigated. The results indicate that with an increase in pile center distance, the peak lateral displacement of the adjacent piles decreases, whereas the peak vertical displacement increases. As the pile length-to-diameter ratio increases, the peak vertical and lateral displacements of the adjacent piles are enhanced. In addition, the peak axial force of the adjacent piles initially decreases and then increases with the penetration depth of the subsequent pile, whereas the peak bending moment initially increases and then decreases. The vertical bearing capacity of the subsequent pile is significantly superior to that of the adjacent piles. Therefore, the effects of pile installation on adjacent piles should be included in pile engineering. The impact of the subsequent pile installation on the bearing capacity of adjacent piles can be significantly reduced by increasing the pile center distance and pile length-to-diameter ratio. The findings provide useful guidance for pile group engineering. [ABSTRACT FROM AUTHOR]

Gravitational waves result from various spacetime-perturbing events which are due to various kinds of motions and changing distributions of mass. Most studies on the source of gravitational waves were derived from the dynamic character of two binary compacted massive objects such as black holes and neutron stars, therefore gravitational waves which originated from a single event source would be of interest. In this paper, we derive the stress–energy tensor (SET) of a braneworld wormhole and demonstrate how the bulk-induced gravitational waves influence the SET of the wormhole. Thus, this study not only suggests a single source of gravitational waves, but also proves the existence of higher dimensional space by providing a formulation, namely, the SET at the wormhole throat affected by the bulk-induced gravitational waves. [ABSTRACT FROM AUTHOR]

Highlights The deformation behavior of uncured thermoset prepreg during hot compaction process was investigated by dividing the whole compaction process into an initial compression stage and the subsequent creep stage. At the compression stage, there existed a strain‐softening phenomenon in the temperature range of 50–90°C, indicating different deformation behavior that is mainly determined by the viscosity of prepreg. Following an appraisal of advantages and limitations of existing compaction models, a combination model consisted of a modified power‐law model including the influence of temperature and the generalized Kelvin‐Voigt model was proposed to describe the deformation behavior of prepreg during compression and creep stage, respectively. Finally, a discussion on the compaction mechanism was conducted to offer some insights into the deformation process. Strain‐softening phenomenon occurred during the compaction of uncured prepreg. Proposed combination model captures the deformation of uncured prepreg well. The percolation mechanism dominates prepreg deformation during compaction. The squeeze flow mechanism causes limited thickness reduction of prepreg. [ABSTRACT FROM AUTHOR]

Dynamic compaction is a soil improvement technique which involves the repeated application of an impact load to a contact area of the soil surface induced by heavy weights. Experimental measurements were prepared for evaluation of the ground wave propagation induced by the rapid impact compaction. Influence of increase of subsoil stiffness during compaction and terrain configuration were investigated. When the shear strength of soil is exceeded during the penetration of the compaction footing, increase of peak particle velocities is slower but still clearly visible along the measurement line. The peak particle velocity is damped by the subsoil below 5 mm s−1 within 40–50 m from the source of excitation. Attenuation radius is affected by the terrain configuration, when terrain elevations cause the increase of acceleration amplitudes. Rigid bodies in the ground, such as foundation structures, could have similar influence. Dominant frequencies are in the interval from 20 to 40 Hz regardless the distance from the source of excitation or the density of the treated subsoil. Obtained results are preferably related to the given boundary conditions. However, wave propagation pattern and change of its characteristics during densification of the subsoil are applicable at another construction sites considering their particularities. [ABSTRACT FROM AUTHOR]

Most RNA-protein condensates are composed of heterogeneous immiscible phases. However, how this multiphase organization contributes to their biological functions remains largely unexplored. Drosophila germ granules, a class of RNA-protein condensates, are the site of mRNA storage and translational activation. Here, using super-resolution microscopy and single-molecule imaging approaches, we show that germ granules have a biphasic organization and that translation occurs in the outer phase and at the surface of the granules. The localization, directionality, and compaction of mRNAs within the granule depend on their translation status, translated mRNAs being enriched in the outer phase with their 5′end oriented towards the surface. Translation is strongly reduced when germ granule biphasic organization is lost. These findings reveal the intimate links between the architecture of RNA-protein condensates and the organization of their different functions, highlighting the functional compartmentalization of these condensates. Biomolecular condensates are often composed of immiscible phases. Here, the authors reveal a functional biphasic organization of germ granules, where translational repression happens in the granule core and translation in the outer phase. [ABSTRACT FROM AUTHOR]

Crack propagation is an important cause of damage to rock bodies. In this study, uniaxial compression tests were conducted on specimens with rock-like mass containing fissures with different inclination angles to study the effect of crack angle on the crack evolution and fracture characteristics of rock bodies. The specimen surface deformation and internal response characteristics during fracture were analyzed via digital image correlation (DIC) and acoustic emission (AE) techniques. The results indicated that the AE characteristics of the fractured specimens exhibited a high degree of activity during the pore compaction and crack propagation stages. The prefabricated fissure configuration affected the stress state at the fissure tip, leading to differences in the crack evolution paths and rupture modes of fissure specimens with different angles. Under the uniaxial peak intensity, the relative position of the normalized global strain curve peak point gradually shifted from the specimen tip to the middle of the specimen as the crack angle increased, which corresponded to the shear damage-tension-shear mixed damage-tension damage modes of the specimen. The findings of this study indicate that normalized global strain curves can reflect the characteristics of crack evolution and provide a basis for the discrimination of fissured rock mass damage modes. [ABSTRACT FROM AUTHOR]