Boundary Configurations Research Articles

A One-Dimensional Nonlinear Consolidation Analysis of Double-Layered Soil with Continuous Drainage Boundary

Based on the soil nonlinearity assumptions proposed by Mesri, the one-dimensional nonlinear consolidation of double-layered soil is investigated. To better align with engineering reality, a continuous drainage boundary is introduced, bolstering the reliability of the derived solution through comparison against existing findings. Subsequently, the consolidation behavior of double-layered soil is analyzed for the soil permeability, compressibility, nonlinear parameters, and interface parameters. The outcomes elicit a positive correlation between the consolidation rate of the double-layered soil and both the ratio of permeability coefficient from the lower to upper soil layers and the value of the interface parameter. Furthermore, it is observed that a lower compressibility coefficient ratio between the lower and upper soil layers, along with a reduced ratio of compression index to penetration index, both contribute to an increased consolidation rate within the context of double-layered soil. The one-dimensional nonlinear consolidation of double-layered soil is intricate, intertwined with the relative permeability and compressibility of soil layers, and the influence of nonlinear parameters and drainage boundary configuration. Integrating these factors is crucial for analyzing the consolidation traits of double-layered soil, leading to a more precise portrayal of the consolidation behavior of coastal soft soils.

Boundaries of the built environment: defining the significance of the material presence of spatial morphology in social life

Settled societies inhabit environments shaped by building activity. Geographic data in social scientific and geographical research are generally composed of architectural and social categories derived from commonplace lived experience and societal knowledge, thus carrying socio-culturally specific meaning. The mundane pragmatism of such categories conflate spaces and buildings with their use and may obstruct effective comparison. Here I introduce a formal redescriptive ontology for built environments that operates on the basis of how differentiation and subdivision constitute distinct occupiable spaces through boundaries. The ontology consists of formally redescriptive socio-spatial and material concepts called ‘Boundary Line Types’ (BLT). I present and photographically illustrate the definitions of the BLTs, which are formulated on a critical realist basis and rooted in a multidisciplinary body of theory concerning the development and inhabitation of built space. Considering inhabited built environments through this ontology foregrounds the emergent logic by which spaces are divided and connected, creating configurations of boundaries as material frames that afford everyday social life. Since BLTs offer transferrable empirical principles from which these material frames emerge, they also enable diachronic and cross-cultural comparative social research. My proposition to approach social scientific built environment research through constitutive material boundaries offers a comparative complement to commonplace and socio-culturally specific spatial categories that compose most geographic data, enabling formal thick redescriptions and the potential for quantitative spatial analysis.

Exploring the complex mechanism of the influence of a multisensory tourism experience on tourists’ mental restoration in the research context of historical and cultural blocks

ABSTRACT Increasing social stress threatens people's mental health. Travelling can effectively relieve mental stress, so the role of tourism experiences in mental restoration is gaining increasing attention. However, no research has examined the mechanism of the embodied effect of tourism experiences on tourists’ mental restoration from a multisensory perspective. Based on sensory marketing theory, a model of multisensory tourism experiences and mental restoration is established, and the boundary conditions and configuration of the former on the latter are considered. Two complementary studies are conducted in the context of historical and cultural districts using structural equation modelling (SEM) and qualitative comparative analysis (QCA). The following conclusions are drawn. First, tourists’ multisensory tourism experience in historical and cultural blocks indirectly improves their mental restoration through the two intermediary psychological processing functions of place attachment and a perceived restorative environment. Second, tourist involvement plays a positive moderating role between multisensory tourism experiences and both place attachment and a perceived restorative environment. Finally, there are no necessary sensory and psychological conditions for high mental restoration, but there are four types of multisensory tourism experience configurations, all of which enable tourists to obtain mental restoration in historical and cultural blocks.

Estimation of Temperature-Dependent Thermal Conductivity and Heat Capacity Given Boundary Data

This work aims to estimate temperature-dependent thermal conductivity and heat capacity given measurements of temperature and heat flux at the boundaries. This estimation problem has many engineering and industrial applications, such as those for the building sector and chemical reactors. Two approaches are proposed to address this problem. The first method uses an integral approach and a polynomial approximation of the temperature profile. The second method uses a numerical solver for the nonlinear heat equation and an optimization algorithm. The performance of the two methods is compared using synthetic data generated with different boundary conditions and configurations. The results demonstrate that the integral approach works in limited scenarios, whereas the numerical approach is effective in estimating temperature-dependent thermal properties. The second method is also extended to account for noisy measurements and a comprehensive uncertainty quantification framework is developed.

Which partners become targets? The role of location in partner acquisitions

This paper seeks to explain how location affects the likelihood of partner acquisition. We develop a novel framework that (i) emphasizes the decoupling between a firm's headquarters and its alliance-making division and their roles regarding alliance management and partner acquisition decisions and (ii) highlights that these decisions are contingent on location-related factors that shape the structural configuration of alliances. Findings from a comprehensive study of 20,165 alliances and 1838 subsequent majority acquisition events reveal that the acquisition likelihood tends to be higher in cross-border alliances than in domestic ones. We further find that increasing national cultural distance between the headquarters of the two partnering organizations attenuates this effect. In contrast, the co-location of the focal firm's alliance-making division and its headquarters further increases the likelihood of acquiring a cross-border partner. We provide a distinct explanation of partner acquisition, placing the interface of location and alliance structure centerstage to explain which alliance partners become acquisition targets. More generally, our findings inform research on strategic decision-making in areas where location is key, such as firm boundary configuration.

Temperature‐dependent electrical conductivity impact on radiative and dissipative peristaltic transport of boron nitride‐ethylene glycol nanofluid through asymmetric channels

AbstractMathematical simulation of biological fluids is of upmost significance due to its numerous medical uses. Interpreting various biological flows necessitates a thorough knowledge of the peristaltic mechanism. This paper presents a computational study for the peristaltic pumping within vertical asymmetric channels filled with BN‐EG nanofluid under the influence of temperature‐dependent electrical conductivity and thermal radiation. Experimental study showed that the nanofluid created by suspending Boron Nitride particles in a combination of Ethylene Glycol exhibited non‐Newtonian characteristics. Further, the Carreau's fluid model provides accurate predictions about the rheological properties of BN‐EG nanofluid. Various configurations of the outer boundaries are considered, namely, square wave, multi‐sinusoidal wave, trapezoidal wave, and triangular wave. A uniform magnetic field together with nanoparticles and mass concentrations, joule heating, first‐order chemical reaction as well as viscous dissipation are considered. Influences of the Dufour and Soret numbers are examined, and the cases of biological scientific assumptions which is known as low Reynolds number and long wavelength are applied. All the computations are obtained numerically using Mathematica symbolical software (ND‐Solve), and the obtained results are presented in terms of the axial velocity u, heat transfer rate Z, concentration profile Ω, temperature profile θ, extra stress tensor , pressure gradient , pressure rise and stream function ψ. The major outcomes revealed that the maximizing in electrical conductivity coefficient, variable viscosity coefficient and magnetic field parameter is better to obtain a higher rate of the heat transfer while the increase in thermo‐diffusion effects as well as linear thermal radiation coefficient causes a reduction in the rate of heat transfer.

Effect of symmetrical and asymmetrical tilt grain boundaries with as the tilt axis on the shock response of bi-crystalline Ni

Aim of this article is to study the effect of tilt grain boundaries on the shock response of single and bi-crystalline nickel. Nickel is commonly used in many structural applications, but research on dynamic response is very limited or in an immature stage. In this article, molecular dynamics-based simulations were performed in conjunction with embedded atom method potential to quantify the response of shock in bi-crystalline Ni containing symmetrical or asymmetrical tilt grain boundaries. Simulations were performed under the influence of adiabatic conditions. Compressive ultra-shock pulse of width 2 ps was simulated in the simulation box; stress, particle velocity, dislocation emission and phase transformation were quantified for symmetrical and asymmetrical tilt grain boundaries in bi-crystalline Ni. It was concluded from the simulations that higher mis-orientation angle between the crystals of Ni help in retarding the shock front velocity and stress. The alternation in the shock front behavior was associated with the change in deformation governing mechanism. The emission of dislocations and formation of Lomer Cottrell lock governs deformation in symmetrical tilt grain boundary configurations under shock pulse loading. It was concluded from the set of simulations that plastic deformation blunts the shock front in bi-crystalline Ni, whereas the sharp shock front was observed in single crystal Ni. Radial distribution function in post shock atomistic configurations was performed to capture the stability of the crystal in post shock scenario. Asymmetrical tilt grain boundaries are not as efficient in restricting the shock front as symmetrical tilt grain boundary configurations.

Simulation and interpretation of MHD peristaltic transport of dissipated third grade nanofluid flow across asymmetric channel under the influences of rheological characteristics and inclined magnetic field as well as heat and mass convection

ABSTRACT Mathematical simulation of biological fluids is of upmost significance due to its numerous medical uses. Interpreting various biological flows necessitates a thorough knowledge of the peristaltic mechanism. This paper presents a computational study for the peristaltic motion within vertical asymmetric channels filled with magnetic third grade nanofluid model under the influences of rheological characteristics. Various configurations of the outer boundaries are considered, namely, square wave, multi-sinusoidal wave, trapezoidal wave, and triangular wave. An inclined magnetic field together with nanoparticles and mass concentrations as well as viscous dissipation are considered. Influences of the Dufour and Soret numbers are examined, and the cases of biological scientific assumptions which is known as low Reynolds number and long wavelength are applied. All the computations are obtained numerically using Mathematica symbolical software (ND-Solve). The major outcomes revealed that the square wave shape gives higher pressure gradients near the inlet and outlet parts while the multi-sinusoidal wave gives periodic behaviors of dp/dx. Also, it is better to maximize the variable viscosity coefficient to enhance the rate of heat transfer while, the rate of heat transfer is diminished by the growth in the thermo-diffusion effects as well as variable thermal conductivity coefficient.

Dielectric prοperties and cοmplex impedance οf the 0.69PbMg1/3Nb2/3Ο3– 0.31PbTiΟ3 relaxοr ceramic

ABSTRACT Impedance spectroscopy assessed dielectric properties of PMN at a single PT concentration. Real and imaginary impedance of (1−x) PMN–xPT materials were analyzed using this technique. Through electrical impedance spectroscopy, the loss tangent factor and electric modulus were determined, leveraging research on semiconductor conduction. The study also presented the synthesis and characterization of solid ceramic lead magnesium nibate-lead titanate (1−x) PbMg1/3Nb2/3-xPbTi3, representing a significant advancement in impedance spectroscopy research. The dielectric behavior was examined by studying the polarization evolution in response to the applied field, aiming to replicate the magnetic phase boundary configuration found in typical ferroelectric behavior. Temperature had a notable impact on the hysteresis loop, with increasing temperature and decreasing applied field resulting in decreased leftover polarization and increased coercive field. The impedance and complex modulus graphs exhibited distinct semicircle patterns attributed to higher grain boundary resistance and capacitance compared to (1−x) PMN-xPT. The Nyquist plot highlighted bulk effects.

Graphene nanoribbons: Current status and challenges as quasi-one-dimensional nanomaterials

The electronic structure of quasi-one-dimensional graphene nanoribbons (GNRs) is closely related to their width, boundary configuration and heteroatomic doping because of the quantum confinement effect and edge effect. Therefore, GNRs present novel electrical, magnetic and optical characteristics. With the advancements in the preparation technology of GNRs, GNRs with different structures have been prepared and studied. Results reveal that GNRs have good photoelectric characteristics, providing them broad application prospects in quantum computing and dissipative microelectronic devices. Herein, we review the research achievements of GNRs in recent years, focus on the advantages and disadvantages of the preparation methods of GNRs and provide some experimental basis for their application.

Controlling Action Space of Reinforcement-Learning-Based Energy Management in Batteryless Applications

Duty cycle management is critical for energy-neutral operation of batteryless devices. Many efforts have been made to develop an effective duty cycling method, including machine learning-based approaches, but existing methods can barely handle the dynamic harvesting environments of batteryless devices. Specifically, most machine learning-based methods require the harvesting patterns to be collected in advance, as well as manual configuration of the duty-cycle boundaries. In this paper, we propose a configuration-free duty cycling scheme for batteryless devices, called CTRL, with which energy harvesting nodes tune the duty cycle themselves adapting to the surrounding environment without user intervention. This approach combines reinforcement learning (RL) with a control system to allow the learning algorithm to explore all possible search space automatically. The learning algorithm sets the target state of charge (SoC) of the energy storage, instead of explicitly setting the target task frequency at a given time. The control system then satisfies the target SoC by controlling the duty cycle. An evaluation based on real implementation of the system using publicly available trace data shows that CTRL outperforms state-of-the-art approaches, resulting in 40% less frequent power failures in energy-scarce environments, while achieving more than ten times the task frequency in energy-rich environments.

Hamiltonian facets of classical gauge theories on E-manifolds

Manifolds with boundary, with corners, b-manifolds and foliations model configuration spaces for particles moving under constraints and can be described as E-manifolds. E-manifolds were introduced in Nest and Tsygan (2001 Asian J. Math. 5 599–635) and investigated in depth in Miranda and Scott (2021 Rev. Mat. Iberoam. 37 1207–24). In this article we explore their physical facets by extending gauge theories to the E-category. Singularities in the configuration space of a classical particle can be described in several new scenarios unveiling their Hamiltonian aspects on an E-symplectic manifold. Following the scheme inaugurated in Weinstein (1978 Lett. Math. Phys. 2 417–20), we show the existence of a universal model for a particle interacting with an E-gauge field. In addition, we generalise the description of phase spaces in Yang–Mills theory as Poisson manifolds and their minimal coupling procedure, as shown in Montgomery (1986 PhD Thesis University of California, Berkeley), for base manifolds endowed with an E-structure. In particular, the reduction at coadjoint orbits and the shifting trick are extended to this framework. We show that Wong’s equations, which describe the interaction of a particle with a Yang–Mills field, become Hamiltonian in the E-setting. We formulate the electromagnetic gauge in a Minkowski space relating it to the proper time foliation and we see that our main theorem describes the minimal coupling in physical models such as the compactified black hole.

Development of technology for standardization of parameters of winter route registration of game animals

The need to develop a new technology for planning survey routes is caused not only by the difficulty of implementing the recommendations of the current methodology for winter route accounting (ZMU) for the “equidistant placement” of survey routes with “observance of a proportional survey of land categories forest, field, swamp”, but also by the inability of the method of grouping the sample into categories of land to reduce the heterogeneity of the examined material. To standardize the placement of accounting routes, the technology of stratification of the territory is put, in which the virtual boundaries of the stratum serve to determine the extrapolation area and the location of the survey route. For the total area of the hunting farm, a tabular, or calculated (for farms with a different area), value of the route length standard, km/thousand ha, is established. The free navigation program SAS Planet determines the length and width of the territory within the boundaries of the hunting area and the principle layout of the registration routes in the strata. According to the algorithms, the following parameters are calculated: the total length of the routes, the average values of the length and width of the territory, the number of strata, the distance between the registration routes, the length of the route in the stratum, the area of the strata, which are necessary for designing the stratification of the territory. On the example of a specific farm with unknown values of parameters, except for the area of the territory, the suitability of algorithms for calculating parameters is shown; a map of the boundaries of the strata and the location of the accounting traces was created; the area of the strata and the design length of the registration route in each stratum were determined; digitized files of traces necessary for work on their reference to the terrain have been created; the technology of binding is given. The results of the study confirmed the manufacturability and simplicity of the method for localizing routes and extrapolation sites, as well as the compatibility of their ordered placement in compliance with a standardized sample size for territories with any area and boundary configuration.

Boundary-dependent urban impacts on timing, pattern, and magnitude of heavy rainfall in Istanbul

An emphasis on whether the modeled response of rainfall to urban signature is consistent across different boundary forcings is lacking. Here, using the Weather Research and Forecasting (WRF) model, we compare urban impacts in the boundary-dependent simulations of a record-breaking rainfall event in Istanbul, designing urban and nourban land cover scenarios. The data used for the boundaries are ECMWF Reanalysis v5 (ERA5) and NCEP Final Analysis (FNL), and we perform simulations with variable boundary and parameterization configurations and use their ensemble mean in our analysis. Our results highlight that some aspects of the urban impact on rainfall produced by different boundary conditions resemble each other. First, hourly rainfall intensifies over and upwind part of the urban domain independent of the employed boundary forcing. Especially within the urban borders, the boost in rainfall amounts during the investigation period totals 6% and 21% for the simulations forced with ERA5 and FNL, respectively. In addition, our simulations exhibit urban signals not only in the rainfall amounts but also in their timing and concentration. This signal in timing is evident by the urban rainfall system that moves slightly ahead of its nourban counterpart at each analyzed hour. We, in particular, observe a spatially less concentrated rainfall pattern as the system positions over the urban area and point out a potential urbanization-topography interaction. We further support these findings with cross-section and integrated water vapor transport analyses. By contrast, the main dissimilarities between the simulations forced with different boundary data include rainfall changes downwind of the city center. This behavior is commensurate with the increase in the temperature and sensible-heat flux values that are not similar in strength in the simulations forced with ERA5 and FNL. These findings suggest that different boundary data can promote similar urban impacts only to some extent, underlining the importance of considering their regional performance before using them in modeling studies.

Numerical Study on the Dynamic Behaviors of Masonry Wall under Far-Range Explosions

As a common enclosure structure, masonry walls are widely used in various types of buildings. However, due to the weak out-of-plane resistance of masonry walls and the generally brittle properties of the materials used for blocks, they are highly susceptible to collapse under blast loads and produce high-speed splash fragments, which seriously threatens the safety of personnel and equipment inside buildings. In this paper, based on the existing tests, a refined numerical simulation model was established to carry out numerical studies of clay tile walls and grouted CMU masonry infill walls under far-range blast loads, and the applicability of the finite element model and parameters were verified. Further, the effects of wall boundary configuration, constraints and dimensions on the dynamic response of the walls were carried out. The results show that: the load distribution on the wall is relatively uniform under the far-range explosion and can be considered as uniform load; the blast-resistant performance of the wall can be enhanced by increasing the grouting rate and the uniformity of grout hole distribution; the boundary configuration of the wall has little effect on the blast resistance, while the boundary constraints and the length and width are the main factors affecting the blast resistance of the wall.

Resolving complex intralayer transition motifs in high-Ni-content layered cathode materials for lithium-ion batteries.

High-Ni-content layered materials are promising cathodes for next-generation lithium-ion batteries. However, investigating the atomic configurations of the delithiation-induced complex phase boundaries and their transitions remains challenging. Here, by using deep-learning-aided super-resolution electron microscopy, we resolve the intralayer transition motifs at complex phase boundaries in high-Ni cathodes. We reveal that an O3 → O1 transformation driven by delithiation leads to the formation of two types of O1-O3 interface, the continuous- and abrupt-transition interfaces. The interfacial misfit is accommodated by a continuous shear-transition zone and an abrupt structural unit, respectively. Atomic-scale simulations show that uneven in-plane Li+ distribution contributes to the formation of both types of interface, and the abrupt transition is energetically more favourable in a delithiated state where O1 is dominant, or when there is an uneven in-plane Li+ distribution in a delithiated O3 lattice. Moreover, a twin-like motif that introduces structural units analogous to the abrupt-type O1-O3 interface is also uncovered. The structural transition motifs resolved in this study provide further understanding of shear-induced phase transformations and phase boundaries in high-Ni layered cathodes.

Simulating and interpretation of MHD peristaltic transport of dissipated Eyring–Powell nanofluid flow through vertical divergent/nondivergent channel

The primary goal of this study is to present a novel suggestion to uncover the characteristic features of the peristaltic flow of Eyring–Powell nanofluid through divergent and nondivergent channels. Several strategies are used to enhance the heat transfer capacity. Heat transport can be improved by increasing the thermal conductivity of the materials using nanoparticles. The implementation of a low Reynolds number and large wavelength hypothesis brings to reduce the system’s complexity. The resulting nonlinear coupled differential equation system is solved numerically by utilizing Mathematica symbolical software (ND-Solve). Various configurations of the outer boundaries are considered, namely, square wave, multi-sinusoidal wave, trapezoidal wave, and triangular wave. Under the effect of pertinent flow parameters, graphical illustrations of axial velocity, thermal, and concentration profiles have been portrayed. In tabular form, numerical outcomes for the rate of heat as well as mass transfers are displayed. One of the most significant phenomena concerning peristaltic motion, known as the trapping phenomenon, has also been spotlighted using contour plots and circulating bolus. The major outcomes revealed that the square wave shape gives higher pressure gradients near the inlet and outlet parts while the multi-sinusoidal wave gives periodic behaviors of It is noteworthy that Eyring–Powell fluid characteristics display a tendency to diminish the thermal resistance and axial velocity near the walls for divergent channels while an enhancement in velocity is observed at the region as Eyring–Powell fluid parameter is altered. Further, for various kinds of divergent channels, the rate of heat transmission is enhanced due to an augmentation in Eyring–Powell fluid characteristics. Also, the present study uncovers that the parameters of the magnetic field and the Eyring–Powell fluid materials have a significant influence on the trapping phenomenon for both types of channels.

Numerical treatment of thermal and concentration convection along with induced magnetic field on peristaltic pumping of a magnetic six-constant Jeffrey nanofluid through a vertical divergent channel

This article presents a computational study for the peristaltic pumping within vertical irregular divergence channels filled with magnetic six-constant Jeffrey nanofluids. Various configurations of the outer boundaries are considered, namely, square wave, trapezoidal wave, multisinusoidal wave, and triangular wave. An induced magnetic field together with nanoparticles and mass concentration are considered. Influences of the Dufour and Soret numbers are examined, and the cases of long wavelength and low Reynolds number are applied. All the computations are obtained numerically via MATHEMATICA symbolical software (built-in command ND-Solve), and the obtained results are presented in terms of the axial velocity current density the function of magnetic force axially induced magnetic field nanoparticle fraction profile concentration profile temperature profile extra stress tensor pressure gradient pressure rise and stream function The major outcomes revealed that the square wave shape gives higher pressure gradients near the inlet and outlet parts while the multisinusoidal wave gives periodic behaviors of Also, higher axial-induced magnetic fields are given at the higher values of the magnetic Reynolds number.

Self-Sustained Euler Buckling of an Optically Responsive Rod with Different Boundary Constraints

Self-sustained oscillations can directly absorb energy from the constant environment to maintain its periodic motion by self-regulating. As a classical mechanical instability phenomenon, the Euler compression rod can rapidly release elastic strain energy and undergo large displacement during buckling. In addition, its boundary configuration is usually easy to be modulated. In this paper, we develop a self-sustained Euler buckling system based on optically responsive liquid crystal elastomer (LCE) rod with different boundary constraints. The buckling of LCE rod results from the light-induced expansion and compressive force, and the self-buckling is maintained by the energy competition between the damping dissipation and the net work done by the effective elastic force. Based on the dynamic LCE model, the governing equations for dynamic Euler buckling of the LCE rod is formulated, and the approximate admissible trigonometric functions and Runge-Kutta method are used to solve the dynamic Euler buckling. Under different illumination parameters, there exists two motion modes of the Euler rod: the static mode and the self-buckling mode, including alternating and unilateral self-buckling modes. The triggering conditions, frequency, and amplitude of the self-sustained Euler buckling can be modulated by several system parameters and boundary constraints. Results indicate that strengthening the boundary constraint can increase the frequency and reduce the amplitude. It is anticipated that this system may open new avenues for energy harvesters, signal sensors, mechano-logistic devices, and autonomous robots.

ONSET OF DARCY-BRINKMAN CONVECTION IN A ROTATING BIDISPERSIVE POROUS MEDIUM

The onset of Darcy-Brinkman convection in a rotating bidispersive porous layer is studied for different boundary configurations. Rotating bidispersive porous layer manifests in many applications such as food and chemical processes, rotating machinery, the petroleum industry, solidification and centrifugal casting of metals, biomechanics, and geophysical problems. Three types of boundary configurations are considered, namely rigid-rigid, rigid-free, and free-free boundaries. The fluid motion is characterized using the Brinkman-Darcy equation with a single temperature in macro and micro phases. The linear stability theory is used, and the obtained eigenvalue problem is addressed analytically for the free-free boundary conditions. The eigenvalue problems for the rigid-rigid and rigid-free boundaries are solved numerically. The effects of the Taylor number, momentum transfer coefficient, permeability ratio, Darcy number, and porosity ratio on the system's stability are graphically explored. The Darcy number, permeability ratio, and Taylor number are found to have a stabilizing influence on the system. Further, it is found that the momentum transfer coefficient shows destabilizing effect. The porosity ratio is found to have a stabilizing impact on the system.