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This paper presents an analytical model to describe the transient fluid flow to a horizontal fracture in frac‐packed vertical wells. A physical model is first established where a horizontal frac‐packed fracture is located in the middle of a cylindrical reservoir. The pressure distribution in the fracture is then derived concerning time and the distance to the wellbore. The analytical model assumes a homogeneous and isotropic reservoir where Darcy's law applies to a single‐phase fluid flow, a radial fracture with a radius much greater than pay zone thickness, and a constant fracture width. For ease of application, a Type Curve Matching approach is introduced which features the matching of a defined dimensionless pressure between field pressure data and model data, and some exemplar curves are illustrated in this paper. The principle of applying curve matching here is to tune model parameters to match the measured pressure/rate data. Once the curves are matched, the model parameters, that is, fracture permeability, etc, are naturally obtained. The validity of the derived model is informed in two ways. The results show that the model will degenerate to the classic radial flow equation for practical values of certain model parameters and upon reasonable simplification. Model validity is further verified by applying the type curve matching technique using field data. This model can be used as a quick and reasonable method to analyze the transient pressure/rate test data to reveal fundamental fracture and reservoir properties for a frac‐packed horizontal fracture at shallow depths where the vertical formation stress is the least in situ stress. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) are the leading cause of death and disability both in the United States and worldwide. Despite high morbidity, mortality, and cost in the United States and global healthcare systems, cardiovascular care has been understudied in the healthcare operations management literature. In this paper, we identify research opportunities for healthcare operations management scholars to aid in improving cardiovascular care. We focus on three burdensome conditions, including (1) coronary artery disease, (2) stroke, and (3) heart failure, which, collectively, lead to the vast majority of CVD‐caused mortality and disability. For each condition, we characterize a typical patient's journey in receiving cardiovascular care, elucidating key challenges in improving care and outlining research questions for healthcare operations management scholars. We close with a reference to new research opportunities that emerge as artificial intelligence is likely to transform much of cardiovascular care. [ABSTRACT FROM AUTHOR]

In this paper, silicon carbide‐based analytical model for gate‐stack dual metal nanowire field effect transistor (gate‐stack DM NW FET) has been analyzed by solving the 2D Poisson's equation using parabolic approximation method for electric potential, subthreshold current and subthreshold slope. The results have been examined for various silicon carbide film depth and channel length. The results predicted by the analytical model have excellent agreement with simulated results obtained by ATLAS 3D device simulator. A gate‐stack having high k‐dielectric material, that is, Hafnium oxide (HfO2) along with aluminum oxide (Al2O3) has been used. Also, performance characteristics of gate‐stack DM NW FET have been compared with the performance characteristics of nanowire field effect transistor (NW FET), Nanowire field effect transistor (NW FET) (Sic) and dual metal nanowire field effect transistor (DM NW FET) (SiC). It is so proved that our proposed device, that is, gate‐stack DM NW FET (4H‐SiC) exhibits superior performance in terms of drain current (Ids), transconductance (gm), output conductance (gd) and cut off frequency (fT) than the existing devices. [ABSTRACT FROM AUTHOR]

Recent work suggests that slab dip may be controlled by differences in dynamic pressure above and below the slab at mid‐asthenospheric depth, motivating exploration of how plate and slab motion are linked to dynamic pressure in the asthenosphere. This paper, the first of two companion papers, presents an analytical method for determining dynamic pressure and velocity in a thin asthenospheric channel, with linear viscosity, consistent with prescribed plate and slab kinematics. Slabs are explicitly incorporated as vertical barriers to asthenospheric flow. Dynamic pressure is expressed as sums of functions with two functional forms, Pedge and Pwall; the former generates discontinuities in velocity (but not pressure) at non‐slab boundaries, and the latter generates discontinuities in pressure (but not velocity) at boundaries with slabs. Application to simple rectangular plate systems demonstrates that asthenospheric velocities within about one trench length of slabs are insensitive to processes on the opposing side of the slab, that dynamic pressure scales linearly with trench length for a given plate aspect ratio and scales approximately linearly with the shortest plate dimension. Although dynamic pressure is quasisymmetrical across convergent plate boundaries that lack slabs, the presence of slabs creates discontinuity and asymmetry in dynamic pressure across subduction zones. When flux of asthenosphere into the lower mantle occurs adjacent to subducting slabs, dynamic pressure is decreased on the side of the slab where down‐flux occurs. This analytical method, applied to systems with multiple arbitrarily shaped plate boundaries, yields excellent results as benchmarked against 3‐D numerical solutions. Key Points: This paper presents an analytical method for determining dynamic pressures for simple and complex plate geometries in Cartesian and spherical domainsDiscontinuities in regional dynamic pressure across slabs are directly linked to slab dip via a force balance involving slab buoyancySimple plate/slab geometries and velocities produce readily quantifiable regional velocity and dynamic pressure fields [ABSTRACT FROM AUTHOR]

In this paper, the bending behavior of prestressed concrete joists strengthened by fiber‐reinforced polymer (FRP) laminates is described. An experimental investigation on 18 large‐scale beams is conducted, allowing determination of the strengthening influence of FRP in the general behavior of prestressed joists. The mechanical parameters considered in the study are the ultimate and elastics loads and the deflection or initial stiffness of joists. The analytical verification is done to calculate the design load values of the floor system. The results indicate that the application of FRP laminates significantly increases the response of prestressed concrete joists. [ABSTRACT FROM AUTHOR]

Adjusting mechanical behavior and controlling deformation parameters are significant tasks in designing shape memory components. In this paper, an analytical model describes the deformation behavior of NiTi/NiTiCu bi‐layer composites under tensile loading. Different deformation stages are considered based on single mechanical behavior at each stage. Closed‐form equations are derived for stress–strain variations of bi‐layer composites under uniaxial loading–unloading. Bi‐layer composites made via the diffusion bonding method from single layers of NiTi alloy with a composition of Ti‐50.7 at.% Ni, as an austenitic layer, and Ti‐45 at% Ni‐5 at% Cu, as a martensitic layer, are produced by the vacuum arc remelting technique. The tensile behavior of single‐ and bi‐layers is investigated by using loading–unloading experiments to find the nominal stress–strain curves. Numerical simulations are also done by employing Lagoudas constitutive model to simulate stress–strain diagrams. The solutions of the analytical method presented are validated by using the numerical simulations as well as the experimental results. With regard to the results obtained from the analytical modeling, the numerical simulations, and the experiments, it is evident that the bi‐layer composites with different thickness ratios provide adjustable mechanical behavior that can be considered in different application designs, for example, actuators equipped with shape memory components. [ABSTRACT FROM AUTHOR]

The paper proposed an analytical queuing theoretic approach to model the network interference in presence of interferers, especially when their interfering transmissions are dependent on each other. The model is validated using simulations and the effects of dependencies among the interferers are also studied. [ABSTRACT FROM AUTHOR]

The preform presents viscoelastic behaviors during the compaction process of flexible guided 3D weaving. The compaction process directly affects the structure of the 3D preform and significantly impacts composite properties. Thus, a viscoelastic model to describe the 3D preform viscoelastic compaction behaviors and a compaction structure model to analyze the causes of the mechanical behavior of the compaction process are originally proposed. The 3D preform compaction experiments with different section area, different number of layers, and different guide structure ratio were conducted to verify the viscoelastic model and the compaction structure model and obtain the influence law on the mechanical behavior. The viscoelastic model can well capture the stress and strain evolution. The compaction structure model can analyze the main structural factors affecting the behavior of compaction mechanical behavior. This work provides a new approach to studying the mechanical behavior in the 3D preform manufacturing process. [ABSTRACT FROM AUTHOR]

The efficiency of matrix–vector multiplication is of considerable importance. No current approaches can optimize this sufficiently well under severe time constraints. All major existing methods are based on either manual‐tuning or auto‐tuning and can therefore be time‐consuming. We introduce an alternative model‐driven approach, which is used to map the implementation of matrix–vector multiplication to a target architecture and analytically obtain its parameters. The approach yields the performance that is competitive with optimized Basic Linear Algebra Subprograms (BLAS)‐like dense linear algebra libraries without the need for manual‐tuning or auto‐tuning. Our method provides competitive performance across hardware architectures and can be utilized to obtain single‐threaded and multi‐threaded implementations on multicore processors. We expect that this approach allows the community to progress from valuable engineering solutions to techniques with a broader application. [ABSTRACT FROM AUTHOR]

An increasing number of online retailers are introducing customer‐to‐manufacturer (C2M) models to offer consumers customized products in addition to standard products. Customized products can satisfy consumers' aesthetic preferences that are unmet by current products. Thus, companies can minimize their misfit costs. Given the trend of this emerging online retail model, this study analytically explores whether and how the introduction of the C2M model affects firms' profits, consumer surplus, and social welfare. Our analyses reveal that the introduction of the C2M model always benefits the retailer; moreover, under certain conditions, a win‐win situation occurs among the retailer, the incumbent manufacturer, and the new manufacturer. Further, the introduction of the C2M model can increase or decrease consumer surplus and foster or hinder social welfare growth, depending on the customization cost and consumers' misfit costs. [ABSTRACT FROM AUTHOR]

The concrete undergoes brittle failure, which is a disadvantage for stability and safety analysis. This drawback was compensated by addition of different types and size of fibers for improving the compressive and fracture characteristics. The incorporation of multi‐scale hybrid fibers in concrete showed enhanced performance at multi‐level than that of single type or size of fiber. This study examined the influence of basalt fiber length (12, 25, 37, and 50 mm) and content (0.15% and 0.3%) on compressive and fracture parameters of hybrid fiber reinforced concrete (HyFRC). Systematic experimentations were performed on mechanical properties which include compressive strength (f'c), toughness index (ɳ) and capability coefficient index (ξ), initial fracture toughness (KiniIC), unstable fracture toughness (KunsIC), and fracture energy (GF). The crack resistance process and fiber‐matrix interaction obtained by scanning electron microscopy analysis were also discussed. The proposed analytical models of HyFRC stress–strain equations indicated great suitability for fitting of experimental behavior with R2 ≥ 0.92. The basalt fiber with different length and contents showed a great potential in HyFRC and indicated a substantial degree of enhancement for the compressive and fracture properties, as compared to that of PC and HyFRC without basalt fiber. [ABSTRACT FROM AUTHOR]

This article presents a Schrödinger–Poisson based technique to predict I−V characteristics of trigate Si fin field effect transistors (FinFETs). The channel characteristics are modeled by a three‐dimensional (3D) Schrödinger wave equation considering quantum‐mechanical ballistic transport. Using a nonequilibrium green function and a 3D Poisson equation, drain current associated with source‐drain Fermi energy difference is evaluated. Contact resistance and its impact on the drain current is adjusted using a modeled parameter in Fermi‐Dirac distribution function. It is observed that the drain current as a function of drain bias saturates because of the finite carrier supply from the source electrode. The model is calibrated using TCAD simulations for quantum transport. To validate the proposed model, output and transfer characteristics of nanoscale FinFETs are compared with experimental data and a good degree of accuracy is observed. It has been demonstrated that the proposed model has the ability to predict FinFETs characteristics having Tfin=3−35nm. [ABSTRACT FROM AUTHOR]

A novel approach for the modeling of rotor‐integrated aerodynamic loads is suggested to answer the need for a comprehensive, insightful, and analytical actuator disc model. All the six degrees of freedom (including tangential components) are considered. It is shown that loads may be written as a quadratic form of a reduced six‐component velocity vector at the hub. The individual contributions of lift and drag, azimuthal variations, as well as blade pitching and tip losses are isolated. Errors introduced by the necessary approximations are discussed, and parametric corrections are considered. Parameter identification methods are then suggested, and the performance of the resulting calibrated analytical models is assessed. Results show that the new modeling approach is able to accurately model both the mean values of the thrust and power coefficients and their derivatives with respect to tip‐speed ratio and pitch angle across the full range of operating wind speeds. Furthermore, it is able to reconstruct the general rotor behavior with a minimal amount of information available. Tangential components are also well modeled, although they require the knowledge of airfoil properties. The model's architecture leaves room for extensions to dynamic flow, skewed flow, and azimuthal load variations. [ABSTRACT FROM AUTHOR]

Salt basins often exhibit a shelf/slope region of extension and a deeper domain of contraction. The up‐slope normal faults in such salt tectonics systems are often associated with the pinch‐out edge of the buried salt layer. Although the spatial correlation between the normal faults and the salt pinch‐out was previously observed, the mechanism was not fully explained. The Levant basin, which is a young and mildly deformed salt basin with a relatively thin overburden, provides an opportunity to analyze a simple salt tectonics system driven by basin margin tilt, and the formation of the normal faults. This work presents analytical and numerical modeling of the coupled viscous salt and overlying visco‐plastic sediment layer. Results suggest the viscosities of both the sediment overburden and salt, as well as their thicknesses, control the deformation of the coupled layers. The visco‐plastic deformation mechanism explains quantitatively the position of faulting and observations of the temporal evolution of brittle deformation in the Levant basin margin. It predicts that the largest stress in the overburden arises above the salt edge, driving normal faulting at that location. Our model also places quantitative constraints on the effective viscosity of the overburden (>2 × 1020 Pa s), which is consistent with experimentally‐determined creep laws. Our results contribute to the understanding of halokinematics in salt basins during the early stages of deformation and will allow better assessment of geological hazards related to salt related deformation. Plain Language Summary: A salt basin is a down‐dropped block of the earth's crustal rocks, in which past evaporation of sea‐water caused deposition of a thick layer of salt and evaporites. For example, during the "Messinian salinity crisis", about 6 Myr ago, the Mediterranean sea partially or fully evaporated, depositing a thick layer of salt. This salt layer got progressively buried under sediments, deep beneath the seafloor. Since such geologically buried salt layers flow like viscous fluids under the weight of accumulated sediments, salt motion often leads to breakage of overlying rock layers. We used combined solid‐fluid mechanics‐based computer and theoretical models to explain and predict the location and timing of such salt‐flow induced sediment breakage. Our work focuses on locations near the edge of the salt, showing that this location is especially prone to breakage (faulting), and explaining the mechanical reason for that. We finally use our model results to explain and predict the timing and locations of faults that are observed near the Israeli shore. Key Points: We simulate and predict the formation of normal faults due to tectonic tilting of the shelf/slope region of a salt basinThe viscosities and thicknesses of the salt and the sediment overburden layers control fault initiationThe predicted faulting process agrees with observations of location and temporal evolution of normal faulting in the Levant basin margin [ABSTRACT FROM AUTHOR]

Herein, oblique cross section (OCS) nanoindentation is used to measure the hardness changes in He2+ ion‐irradiated oxide dispersion strengthened (ODS) steel MA957, to obtain the hardness profile through the thickness, and correlate it with the damage dose profile. Following this, the dispersed barrier hardening (DBH) model is implemented to calculate the hardness of each layer of the irradiated material, based on the displacement damage and He concentration from simulations. Next, a simplified analytical model for the measured hardness at different depths is developed with the assumption that the plastic zone under the indenter is hemispherical and the hardness measured at any given depth depends on the average hardness of the plastic zone volume. This analytical model is implemented with the help of a program written in MATLAB. The calculated hardness profile is compared with the experimental profile, and it is found to be in reasonably good agreement for different energies of the irradiating He ions. This model can be used not only for ion‐irradiated materials with varying doses in different layers but also for other metallic materials with surface layers having diffuse interfaces. [ABSTRACT FROM AUTHOR]

The temporal delay in the water table's response to precipitation is a common phenomenon. Using a mathematical model, we developed a function that represents the recharge flux through unsaturated zones of varying thickness to model the delayed response of groundwater level due to precipitation. The recharge flux from the developed function was integrated into the analytical and numerical models to estimate the actual groundwater levels in the unsaturated zone. The analytical and numerical models accurately determined the actual groundwater levels. Additionally, calibrated hydraulic parameters from numerical estimates reflected the values measured in the actual aquifer, thereby highlighting the potential application of the developed function to wide‐ranging groundwater problems. Based on the recharge function, a recharge module can be developed for existing flow simulators to enhance groundwater modeling. Plain Language Summary: The delay (ranging from minutes to months) in the change in the groundwater level due to precipitation is common. If this delay is neglected, then erroneous estimates of the groundwater flow and solute transport are inevitable. Most of the models on ground water estimation are incapable of assessing delayed groundwater response (practically evaluated with great difficulty). To overcome these limitations, in this study, a statistical function representing the delayed recharge flux through the unsaturated zone is derived. To validate the function, delayed recharge fluxes were obtained by calibrating the developed function using actual groundwater level data of a few locations. Then, the fluxes were applied to analytical and numerical models for groundwater level estimation. The results reasonably reflected the actual groundwater levels and aquifer hydraulic properties, indicating that the developed function is useful in resolving real‐world problems. Key Points: A function representing the delayed recharge flux through unsaturated zones of varying thickness was derivedThe recharge flux from the function was integrated into analytical and numerical models, producing consistent resultsThe function can be combined with existing models to simulate more realistic groundwater flow and solute transport [ABSTRACT FROM AUTHOR]

We investigate the relationship between the global distribution of deep slab dips (at 250‐ to 300‐km depth) and pressure and circulation in the upper mantle. Using an analytic method to compute dynamic pressure in a 3‐D global upper mantle domain, and a force balance between slab dip, slab buoyancy, and pressure, we model dips for all major subduction zones. Overall, our models suggest that global‐scale mantle flow, as dictated by the shapes and velocities of Earth's plates and slabs, plays a fundamental role in creating the global pattern of slab dips. The dip trends of the South American and western Pacific subduction zones are controlled, in our models, by spatial variations in the dynamic pressure associated with flow. Our best fitting models produce global root mean square dip misfits of less than 10° for asthenospheric viscosities of 2.5–4.0 × 1020 Pas. This result is only obtained with a large flux of asthenosphere from upper to lower mantle at subduction boundaries, occurring on the overriding plate side of slabs, without which dips are significantly steeper than observed. This effect cannot be resolved by processes that affect only certain subduction systems and requires flux of asthenosphere into the lower mantle at subduction systems globally (or an alternative mechanism that produces more negative pressures on the overriding plate side of slabs). Upper mantle pressure fields that fit global slab dips yield negative dynamic pressure on the upper plate side of slabs, positive pressure on the subducting plate side, and an east‐to‐west pressure increase beneath the Pacific Plate. Key Points: By linking dip to mantle pressure via a force balance, we investigate global mantle flow as constrained by the Earth's slab dip distributionModels produce pressure fields consistent with Earth dips when material is down fluxed into the lower mantle on the upper plate side of slabsSlab dips provide a constraint on dynamic pressure patterns in the upper mantle [ABSTRACT FROM AUTHOR]

In recent years, the assessment of the shear resistance of existing post‐tensioned multispan bridges has become a frequent task for civil engineers. New models developed for this purpose need to be verified, since the number of shear‐related results of tests executed under real loading conditions at the interior support of multispan systems is very limited. In this study, eight shear tests carried out on four specimens are presented. The effects of different prestressing grades, cross‐sections, and amounts of transverse reinforcement are investigated. Two test setups were used in order to reproduce the internal forces occurring at the interior and end supports, respectively, of actual multispan bridges. With the aid of close‐range photogrammetry, detailed measurements of the kinematics of the critical flexural‐shear cracks were performed. In this study, it is demonstrated that arching action plays a major role for the shear capacity of slender post‐tensioned beams. The predictions of the shear capacity determined with various shear design models show that these models are conservative, especially with respect to the shear capacity for the region around the interior supports. However, the evaluation of the models also shows that the flexural‐shear crack model yields very promising results of the shear capacity of post‐tensioned beams with low shear reinforcement ratios. [ABSTRACT FROM AUTHOR]

We investigate whether, in spite of the existence of cross‐market network externalities, platform competition can lead to segmentation of the two sides of the market served by the platforms. We address this question in the context of competition between two equity crowdfunding platforms that connect startups looking for capital with prospective investors. Given the heterogeneity in the populations of startups and investors in terms of the riskiness of the former population and the degree of risk aversion of the latter population, we investigate whether there exists an equilibrium where the two populations are segmented to ensure an improved match between them. We find that the segmenting equilibrium can arise only when compatibility in terms of their risk profiles is of high importance to both populations, and compatibility is significantly more important than the size of the network externality considered by startups. Segmentation is likely to improve the welfare of both populations when the basic benefit from any kind of match is relatively high. [ABSTRACT FROM AUTHOR]

We investigate the 24–27 December 2018 eruption of Mount Etna occurred from fissures located on the volcano eastern flank and accompanied by a seismic swarm, which was triggered by the magma intrusion and continued for weeks after the end of the eruption. Moreover, this swarm involved some of the shallow volcano‐tectonic structures located on the Mount Etna flanks and culminated on 26 December with the strongest event (ML 4.8), occurred along the Fiandaca Fault. In this work, we analyze seismological data and Sentinel‐1 Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements, the latter inverted through analytical modeling. Our results suggest that a dike source intruded, promoting the opening of the eruptive fissures fed by a shallower dike. Moreover, our findings indicate that the activation of faults in different sectors of the volcano may be considered as a response to accommodate the deformations induced by the magma volumes injection. Key Points: We investigate the ground displacements and the 3D source geometry of the December 2018 Mount Etna (Italy) volcano‐tectonic crisisDInSAR data obtained from SAR data pairs collected by Sentinel‐1 have been inverted through analytical modelingOur results suggest the presence of two volcanic sources: a shallow dike and a deeper one associated with a long‐term seismic swarm [ABSTRACT FROM AUTHOR]

Multistage hydraulic fracturing has become a common well completion for horizontal shale gas wells. Some well test data from horizontal shale gas wells have shown pseudo‐steady flow conditions after a period of production. Considering linear flow from reservoir to fracture and linear flow in the fracture, an analytical model is established to calculate the productivity of horizontal shale gas wells under pseudo‐steady flow conditions. The equations in the analytical model are very simple. The production rates calculated by the analytical productivity model are in good agreement with actual gas wells production rates of a well in North American field and 12‐2 well in Fuling shale gas reservoir of China. Sensitivity analysis with the analytical productivity model shows that the different matrix permeability corresponds to the different reasonable fracture conductivity, and the higher the matrix permeability is, the greater the reasonable fracture conductivity. In the process of fracturing for a well, in order to increase production and save fracturing costs, there is no need to generate high‐conductivity fractures, the reasonable fracture conductivity should be determined based on economic evaluations in the real production process. The analytical model provides a practical way to predict production rate for optimization of fracturing design. Multistage hydraulic fracturing has become a common well completion for horizontal shale gas wells. Some well test data from horizontal shale gas wells have shown pseudo‐steady flow conditions after a period of production. Considering linear flow from reservoir to fracture and linear flow in the fracture, an analytical model is established to calculate the productivity of horizontal shale gas wells under pseudo‐steady flow conditions. [ABSTRACT FROM AUTHOR]

Abstract: The causative source of the first damaging earthquake instrumentally recorded in the Island of Ischia, occurred on 21 August 2017, has been studied through a multiparametric geophysical approach. In order to investigate the source geometry and kinematics we exploit seismological, Global Positioning System, and Sentinel‐1 and COSMO‐SkyMed differential interferometric synthetic aperture radar coseismic measurements. Our results indicate that the retrieved solutions from the geodetic data modeling and the seismological data are plausible; in particular, the best fit solution consists of an E‐W striking, south dipping normal fault, with its center located at a depth of 800 m. Moreover, the retrieved causative fault is consistent with the rheological stratification of the crust in this zone. This study allows us to improve the knowledge of the volcano‐tectonic processes occurring on the Island, which is crucial for a better assessment of the seismic risk in the area. [ABSTRACT FROM AUTHOR]

The interaction between the solar wind and Jupiter's magnetic field confines the planetary field to the largest magnetosphere in the Solar System. However, the full picture of when and where key processes operate at the magnetopause boundary of the system remains unclear. This is essential for testing understanding with observations and for determining the relative importance of different drivers of Jovian magnetospheric dynamics. Here we present a global analytical model of Jovian magnetopause conditions under steady state, which forms the basis of boundary process assessments. Sites of magnetic reconnection at Jupiter's magnetopause are expected to be in regions of sufficiently high magnetic shear across the boundary, controlled by the orientation of the interplanetary magnetic field. Reconnection rates are also most sensitive to changes in the highly variable IMF, followed by changes in the solar wind plasma mass density. The largest plasma flow shear across the boundary is in the equatorial dawn region, producing a region that is typically unstable to growth of the Kelvin-Helmholtz (K-H) instability. Compared to magnetopause reconnection site locations, this K-H-unstable region at dawn is less sensitive to changing conditions. Motion of K-H boundary perturbations typically includes dawn-to-dusk motion across the subsolar region. Model-predicted reconnection voltages are typically hundreds of kV but rely on steady solar wind conditions on a time scale that is longer than typical at Jupiter's orbit. How the reconnection voltage compares to the voltage applied due to the 'viscous-like' interaction involving K-H instability remains unclear. [ABSTRACT FROM AUTHOR]

A pavement outcrop with excellent exposure of spatial relationships among joints, veins, small offset normal faults, and associated alteration halos (redox fronts) provided an opportunity to compare predictions of analytical models for reaction front propagation in a fracture-matrix system with a real-field situation. The results have important implications for fluid flow and pollutant transport through a fractured medium. The alteration halos observed suggest that all joints of different sets and most small faults are conductive to meteoric water at shallow depth. On the other hand, veins are local barriers to mass transport by diffusion. By using petrologic and petrophysical data, analytical modeling, and the width of the alteration halos, it was possible to estimate when the fracture network was open to fluid flow. The inferred time for fluid flow and diffusion through the fracture network is sensitive to the porosity n of the rock matrix used in the analytical solutions: 2200 ± 500 years with n = 0.08, 4600 ± 900 years with n = 0.05, and 16,000 ± 4000 with n = 0.02. The second and third age determinations are consistent with the landscape evolution of the area since the end of the last Wűrmian ice age and with the timing required to fill the fractures observed in outcrop. We suggest that analytical modeling is an important tool for the determination of transport and reaction time scales in fractured formations where it is constrained by a robust petrophysical and chemical properties data set. [ABSTRACT FROM AUTHOR]

In the past few years, the use of carbon fibre reinforced polymer (CFRP) has increased, because of their high strength, in concrete elements such as shear walls. In this study, the behaviour of a shear wall strengthened with different layout configurations of CFRP under lateral loading was investigated. For this purpose, a model is first verified in laboratory work, then in the next step the models were analysed by increasing the number of fibre layers and the effect of fibre layers on shear wall capacity was studied. Sliding between fibres and concrete was neglected. Also the effect of increasing the concrete strength of a reinforced concrete (RC) wall on CFRP strengthening was studied. In all models, comparisons were made between the results of CFRP configurations in increasing lateral strength and also ductility. Finally, by comparing the results, the best fibre configuration was determined based on the maximum load capacity. [ABSTRACT FROM AUTHOR]

In the presented work, influence of magnet shaping on cogging torque of surface-mounted Permanent Magnet (PM) machines is investigated. The considered PM shape for the magnet shaping is the loaf-shape PM with off-set arcs. For the first time, based on the solution of the Poissons's equation, an analytical model is provided to predict the magnetic flux density of the slotted-armature and surface-mounted PM machines with the loaf-shape PM. The influence of the slotted armature on the magnetic flux density is taken into account by considering the slot virtual surface currents. The geometry of the loaf-shape PM is formulated and optimized to reach a design with a low value of the cogging torque. The machine cogging torque is computed by the Maxwell stress tensor. The obtained analytical model is used as the computational tool to find the dependence of the machine cogging torque on the PM geometry. Finally, the validity of the obtained results is verified by finite element analysis. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The semiconductor industry has implemented the technique of wrapping the gate electrode on different sides of channel to mitigate the degrading electrostatic effects in nanometer transistor. Intel adopted trigate architecture, wherein the channel is surrounded by gate electrode on three sides to improve the gate control over the channel. In order to further enhance the performance and diminish the short channel effects, triple material trigate silicon‐on‐insulator (SOI) MOSFET is explored in this work. An analytical model to determine the device electrostatics and match deviations due to device geometry has also been developed. The consequence of quantum confinement effects (QMEs), which arise due to ultra‐thin body structure, on the inversion charge and threshold voltage has also been included. Thus, the analytical model presented in this work is based on a self‐consistent solution of three‐dimensional Poisson's equation and two‐dimensional Schrodinger equation with proper boundary conditions. The model is verified by the uniformity obtained between the results from analytical model and TCAD simulations. The superiority of the device has been demonstrated by comparing performance parameters like potential distribution, field variations, drain induced barrier lowering (DIBL) with already existing device structures like single material trigate (SMTG) and dual material trigate (DMTG) SOI MOSFETs [ABSTRACT FROM AUTHOR]