Journal articles: 'Layered Data Structure'

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Tang, Yan, Jianwu Wang, Mai Nguyen, and Ilkay Altintas. "PEnBayes: A Multi-Layered Ensemble Approach for Learning Bayesian Network Structure from Big Data." Sensors 19, no. 20 (October 11, 2019): 4400. http://dx.doi.org/10.3390/s19204400.

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Discovering the Bayesian network (BN) structure from big datasets containing rich causal relationships is becoming increasingly valuable for modeling and reasoning under uncertainties in many areas with big data gathered from sensors due to high volume and fast veracity. Most of the current BN structure learning algorithms have shortcomings facing big data. First, learning a BN structure from the entire big dataset is an expensive task which often ends in failure due to memory constraints. Second, it is quite difficult to select a learner from numerous BN structure learning algorithms to consistently achieve good learning accuracy. Lastly, there is a lack of an intelligent method that merges separately learned BN structures into a well structured BN network. To address these shortcomings, we introduce a novel parallel learning approach called PEnBayes (Parallel Ensemble-based Bayesian network learning). PEnBayes starts with an adaptive data preprocessing phase that calculates the Appropriate Learning Size and intelligently divides a big dataset for fast distributed local structure learning. Then, PEnBayes learns a collection of local BN Structures in parallel using a two-layered weighted adjacent matrix-based structure ensemble method. Lastly, PEnBayes merges the local BN Structures into a global network structure using the structure ensemble method at the global layer. For the experiment, we generate big data sets by simulating sensor data from patient monitoring, transportation, and disease diagnosis domains. The Experimental results show that PEnBayes achieves a significantly improved execution performance with more consistent and stable results compared with three baseline learning algorithms.

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Marsan, A. L., and D. Dutta. "Construction of a Surface Model and Layered Manufacturing Data From 3D Homogenization Output." Journal of Mechanical Design 118, no. 3 (September 1, 1996): 412–18. http://dx.doi.org/10.1115/1.2826901.

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A homogenization method has been recently developed to optimize the topology of a structure. This method will suggest a structural topology, but the results will be in finite element form. Most engineering applications, however, require smooth structures, whether the faces of the structures be planar or curved. Given the topology of a three-dimensional structure as suggested by the homogenization method, an algorithm is developed to interpret the structure and generate a smooth, manufacturable surface representation of the structure. Structures designed by the homogenization method can be quite complex and traditional manufacturing technique may not be well suited for constructing them. Layered manufacturing is adopted for producing such structures and it is shown how to generate the necessary data for this novel manufacturing technique from the surface model of the structure. Some steps of the algorithm require designer inputs. Examples are given which demonstrates this algorithm.

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Auken, Esben, and Anders Vest Christiansen. "Layered and laterally constrained 2D inversion of resistivity data." GEOPHYSICS 69, no. 3 (May 2004): 752–61. http://dx.doi.org/10.1190/1.1759461.

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In a sedimentary environment, quasi‐layered models often can represent the actual geology more accurately than smooth minimum‐structure models. We present a 2D inversion scheme with lateral constraints and sharp boundaries (LCI) for continuous resistivity data. All data and models are inverted as one system, producing layered solutions with laterally smooth transitions. The models are regularized through lateral constraints that tie interface depths or thicknesses and resistivities of adjacent layers. A priori information, used to resolve ambiguities and to add, for example, geological information, can be added at any point of the profile and migrates through the lateral constraints to parameters at adjacent sites. Similarly, information from areas with well‐resolved parameters migrates through the constraints to help resolve areas with poorly constrained parameters. The estimated model is complemented by a full sensitivity analysis of the model parameters supporting quantitative evaluation of the inversion result. A simple synthetic model proves the need for a quasi‐layered, 2D inversion when compared with a traditional 2D minimum‐structure inversion. A 2D minimum‐structure inversion produces models with spatially smooth resistivity transitions, making identification of layer boundaries difficult. A continuous vertical electrical sounding field example from Sweden with a depression in the depth to bedrock supports the conclusions drawn from the synthetic example. A till layer on top of the bedrock, hidden in the traditional inversion result, is identified using the 2D LCI scheme. Furthermore, the depth to the bedrock surface is easily identified for most of the profile with the 2D LCI model, which is not the case with the model from the traditional minimum‐structure inversion.

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Wang, Tan K., and S. C. Tan. "Inverse-Ray Imaging of 2D Layered Structures from Seismic Reflection Data." Journal of Mechanics 19, no. 1 (March 2003): 191–96. http://dx.doi.org/10.1017/s1727719100004202.

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ABSTRACTShooting angle of an inverse ray for imaging 2D multi-layered structures from reflected travel-times is derived in a closed form. By considering the normal incidence of two neighboring rays reflected at interfaces when sources are at the same locations as receivers, the traveling distance and direction of two inverse-rays are determined successively from the lowermost layer to the uppermost layer. This approach is similar to and also confirmed with the Huygens' principle that the equal travel-time along a wave front (perpendicular to the rays) is conserved. The closed-form solution of the inverse rays is further applied to image a complex structure of a ramp-flat fault with eleven layers. The results demonstrate that the inverse-ray imaging from travel-time picks of all layers is superior to that picked by a layer-stripping approach.

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Kongshaug, Kjell Ove, Helmer Fjellvåg, and Karl Petter Lillerud. "Layered aluminophosphates I. Crystal structure of two novel layered aluminophosphates solved ab initio from powder diffraction data." Microporous and Mesoporous Materials 32, no. 1-2 (November 1999): 17–28. http://dx.doi.org/10.1016/s1387-1811(99)00084-0.

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Douma, Jan. "The effect of transverse isotropy on isotropic traveltime inversion of vertical seismic profile data—A modeling study." GEOPHYSICS 55, no. 9 (September 1990): 1235–41. http://dx.doi.org/10.1190/1.1442939.

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Traveltime inversion of multioffset VSP data can be used to determine the depths of the interfaces in layered media. Many inversion schemes, however, assume isotropy and consequently may introduce erroneous structures for anisotropic media. Synthetic traveltime data are computed for layered anisotropic media and inverted assuming isotropic layers. Only the interfaces between these layers are inverted. For a medium consisting of a horizontal isotropic low‐velocity layer on top of a transversely isotropic layer with a horizontal axis of symmetry (e.g., anisotropy due to aligned vertical cracks), 2-D isotropic inversion results in an anticline. For a given axis of symmetry the form of this anticline depends on the azimuth of the source‐borehole direction. The inversion result is a syncline (in 3-D a “bowl” structure), regardless of the azimuth of the source‐borehole direction for a vertical axis of symmetry of the transversely isotropic layer (e.g., anisotropy due to horizontal bedding).

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Ghiu, Camil-Daniel, and Yogendra K. Joshi. "Boiling Performance of Single-Layered Enhanced Structures." Journal of Heat Transfer 127, no. 7 (February 2, 2005): 675–83. http://dx.doi.org/10.1115/1.1924568.

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A study of pool boiling at atmospheric pressure from single-layered enhanced structures was conducted for a dielectric fluorocarbon liquid (PF 5060). The parameters investigated in this study were: (a) Heat flux (1-45W∕cm2); (b) width of the microchannels (65-105μm); and (c) microchannel pitch (0.2-0.7mm). The boiling performance of the enhanced structures was found to increase with the increase in channel width and decrease in channel pitch. A simple single line curve fit is provided as a practical way of predicting the data over the entire nucleate boiling regime. The exponent n in the single line power curve fit was found to be between 1 and 2. The modes of boiling from an enhanced structure proposed by previous researchers were unable to explain the boiling curves obtained in this study. The present data are explained in light of the contribution from the top finned surface of the enhanced structure.

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Bailey, James A., R. Brian Dyer, Darla K. Graff, and Jon R. Schoonover. "High Spatial Resolution for IR Imaging Using an IR Diode Laser." Applied Spectroscopy 54, no. 2 (February 2000): 159–63. http://dx.doi.org/10.1366/0003702001949122.

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By coupling an infrared diode laser to a conventional infrared microscope, one achieves resolution approaching the diffraction limit while enabling rapid data collection. This technique is demonstrated with the use of a layered polymer sample that has been contaminated by migration of a volatile additive from an exogenous source. The distribution of this additive in the layered structure is shown to correlate with specific layers and reveals a concentration gradient suggesting a diffusive mechanism of additive migration parallel to the layered structure.

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Li, Ji, Shaoqing Shi, Weiming Luo, and Qifan Wang. "Study on Explosion-Resistance of Biomimetic Layered Honeycomb Structure." Advances in Civil Engineering 2020 (February 19, 2020): 1–15. http://dx.doi.org/10.1155/2020/5356145.

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A new type of explosion-resistant biomimetic layered honeycomb structure was designed based on the natural mechanism and biological inspiration, which was mainly composed of a sacrificial layer and a bearing layer. The shock tube device was adopted to analyze the dynamic response of the biomimetic layered honeycomb structure under the action of explosion load in order to obtain the deformation modality, deflection data, and strain time-history curve of the structure. It turns out that the maximum deformation deflection of the back panel of the structure is only 28 mm. Compared with the structure of single-layer honeycomb, the independent sacrificial layer, and bearing layer, the biomimetic layered honeycomb structure has good explosion-resistant performance and can repeatedly bear multiple explosion loads. Besides, equivalent homogenization theory was employed to carry out numerical simulation. The results show that the numerical simulation results are perfectly in line with the results of experiments, and the numerical simulation method is proven to be feasible and effective. Under the action of explosion load, the biomimetic layered honeycomb structure absorbs energy mainly by sacrificial layers that are in layered and staggered arrangement. In addition, the sharp rangeability of the kinetic energy of bearing layer structure indicates that it has the feature of large mass, which can be used as the bearing part of the biomimetic layered honeycomb structure.

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Ovchinnikov, Alexander, Hua He, and Svilen Bobev. "Crystal structure of the layered arsenide Rb3Cu3As2." Acta Crystallographica Section C Structural Chemistry 74, no. 12 (November 22, 2018): 1715–18. http://dx.doi.org/10.1107/s2053229618014341.

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The crystal structure of a new arsenide, Rb3Cu3As2 (trirubidium tricopper diarsenide), has been established from single-crystal X-ray diffraction data. This compound crystallizes in the K3Cu3P2 type, with layers of interlinked CuAs2 units. The partitioning of the available valence electrons yields the charge-balanced composition (Rb+)3(Cu+)3(As3–)2, placing this phase in a broad field of transition-metal-containing Zintl phases. First-principles calculations confirm a semiconducting ground state, in accordance with electron-counting considerations. Chemical bonding analysis reveals strong covalent Cu—As bonds and ionic Rb...As interactions. In addition, a weak attraction is found between the Cu atoms, possibly pointing toward cuprophilic interactions.

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Kaga, Motoaki, Hirokazu Kurachi, Toru Asaka, Bing Yue, Jinhua Ye, and Koichiro Fukuda. "Crystal structure of layered perovskite compound, Li2LaTa2O6N." Powder Diffraction 26, no. 1 (March 2011): 4–8. http://dx.doi.org/10.1154/1.3543992.

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The crystal structure of Li2LaTa2O6N was determined from laboratory X-ray powder diffraction data (Cu Kα1) using the Rietveld method. The title compound is tetragonal with space group I4/mmm, Z=2, and unit-cell dimensions a=0.395 049(4) nm, c=1.850 97(3) nm, and V=0.288 869(6) nm3. The initial structural model was successfully derived by the direct methods and further refined by the Rietveld method, with the anisotropic atomic displacement parameters being assigned for all atoms. The final reliability indices were Rwp=5.73%, S=1.46, Rp=4.33%, RB=1.13%, and RF=0.53%. Li2LaTa2O6N has a layered perovskite structure similar to that of Li2LaTa2O7.

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Aparna, H., B. Bhumijaa, R. Santhiyadevi, K. Vaishanavi, M. Sathanarayanan, Amirtharajan Rengarajan, Padmapriya Praveenkumar, and Ahmed A. Abd El-Latif. "Double layered Fridrich structure to conserve medical data privacy using quantum cryptosystem." Journal of Information Security and Applications 63 (December 2021): 102972. http://dx.doi.org/10.1016/j.jisa.2021.102972.

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Peng, Ronghua, Bo Han, Xiangyun Hu, Jianhui Li, and Yajun Liu. "Transdimensional Bayesian inversion of magnetotelluric data in anisotropic layered media with galvanic distortion correction." Geophysical Journal International 228, no. 3 (October 11, 2021): 1494–511. http://dx.doi.org/10.1093/gji/ggab413.

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SUMMARY Presence of electrical anisotropy in the lithosphere can provide useful constraints on regional structure patterns and dynamics of tectonic processes, and they can be imaged by magnetotelluric (MT) data. However, Inversion of MT data for anisotropic structures using standard gradient-based approaches requires subjective choices of model regularization for constraining structure and anisotropy complexity. Furthermore, the ubiquitous presence of galvanic distortion due to small-scale near-surface conductivity inhomogeneities prevents accurate imaging of subsurface structures if ignored or not properly removed. Here, we present a transdimensional Bayesian approach for inverting MT data in layered anisotropic media. The algorithm allows flexible model parametrization, in which both the number of layers and model parameters of each layer are treated as unknowns. In this manner, the presence or absence of anisotropy within the layers, as well as the level of model complexity, is determined adaptively by the data. In addition, to account for the effects of galvanic distortion, three frequency-independent distortion parameters resulting from the distortion decomposition are treated as additional variables during the inversion. We demonstrate the efficiency of the algorithm to resolve both isotropic and anisotropic structures with synthetic and field MT data sets affected by galvanic distortion effects. The transdimensional inversion results for the field data are compatible with results from previous studies, and our results improve the constraints on the magnitude and the azimuth (i.e. most conductive direction) of electrically anisotropic structures. For practical applications, the validity of 1-D anisotropic approximation should be first tested prior to the use of our approach. Otherwise it may produce spurious anisotropic structures due to the inapplicability of the anisotropic 1-D inversion for MT data affected by 2-D or 3-D electrical resistivity structures.

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de Groot-Hedlin, Catherine D., and Frank L. Vernon. "An evolutionary programming method for estimating layered velocity structure." Bulletin of the Seismological Society of America 88, no. 4 (August 1, 1998): 1023–35. http://dx.doi.org/10.1785/bssa0880041023.

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Abstract For most geophysical inverse problems, one solves for an Earth model that minimizes the misfit between the observed data and observational predications determined from forward modeling. However, the solutions to such problems are almost always nonunique, as some of the model parameters are poorly resolved by the data. We have developed a novel form of evolutionary programming (EP) that solves directly for a broad cluster of models that adequately fit the data. We obtain improved performance of the EP algorithm by rotating the model parameter axes at each generation so that the axes are aligned perpendicular and parallel to long valleys in the misfit surface. The rotated axes are defined by the eigenvectors of the covariance matrix of the set of models; the mutation rate in each new direction varies with the square root of the corresponding eigenvalue. This modified EP method finds a wide range of models satisfying the data, allowing one to determine the uncertainty in the model parameters. We illustrate this EP method by applying it to the problem of determining velocity structure from regional travel-time data. Application of this method to a travel-time data set generated from a model that includes a low-velocity zone (LVZ) illustrates that it successfully finds a wide range of models within the broad minimum that includes the initial solution. We apply the method to regional travel-time data recorded at the Kyrgyz broadband network (KNET) and find that velocities are well resolved, except at depths of 25 to 50 km.

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Dickens, Thomas A. "Diffraction tomography for crosswell imaging of nearly layered media." GEOPHYSICS 59, no. 5 (May 1994): 694–706. http://dx.doi.org/10.1190/1.1443627.

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Diffraction tomography is a high‐resolution imaging technique applicable to the mapping of formation velocities away from the borehole, achieving a spatial resolution of better than one acoustic wavelength when used to image synthetic model data. However, traditional filtered back‐propagation diffraction tomography algorithms are based on weak‐scattering and constant‐background velocity assumptions, which limits their applicability to models of realistic structural complexity. Results are obtained using a new, computationally efficient single‐mode (P‐wave) diffraction tomography algorithm that is applicable to models, including geologically realistic ones, whose strongest variations can be approximated as a set of horizontal layers. The algorithm starts with a layered model of the subsurface velocity structure, which may be constructed from well logs or by using traveltime tomography. Application of layered diffraction tomography updates this model to reveal 2-D structures such as faults, pinch‐outs, and dips. An overview of the layered diffraction tomography algorithm and information on its computational implementation are presented. Layered diffraction tomography can, given an accurate initial model, successfully image complex structures for which filtered back‐propagation fails, with a spatial resolution on the order of one‐third wavelength. Synthetic crosswell data are used to construct images of models ranging from an isolated simple target to geologically realistic structures containing faults, erosional surfaces, and dipping beds. The initial layered model must represent the actual subsurface structure with as much fidelity as possible; it is important to use all available a priori information in the construction of this model. The enhanced spatial resolution provided by diffraction tomography does not require the use of high‐angle reflections; in the presence of noise, image quality and resolution can be largely maintained by using only a short time window of (the high S/N) data immediately following the first break that is employed for traveltime imaging.

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Glazunov, A. V., E. V. Mortikov, K. V. Barskov, E. V. Kadancev, and S. S. Zilitinkevich. "The layered structure of stably stratified turbulent shear flows." Известия Российской академии наук. Физика атмосферы и океана 55, no. 4 (September 17, 2019): 13–26. http://dx.doi.org/10.31857/s0002-351555413-26.

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The data of numerical simulation of stably stratified turbulent Couette flows are analyzed for various values of the Richardson number. Two different methods were used: Direct Numerical Simulation (DNS) and Large Eddy Simulation (LES). It is shown that the flow contains large organized structures, along with chaotic turbulence, regardless of the simulation method. These structures appear as inclined layers in the temperature field with weakly stable stratification, separated by very thin layers with large temperature gradients. The existence of such layered structures in nature is indirectly confirmed by the analysis of field measurement data on the meteorological mast, where temperature gradient distribution histograms are found to be far from the normal distribution and similar to temperature gradient probability distributions obtained by numerical models data. The simulations indicate an increase of the turbulent Prandtl number with increasing of the gradient Richardson number. It is highly likely that the identified structures serve as effective barriers for vertical turbulent heat flux, without the blocking of momentum transfer. We proposed the hypothesis, that it is precisely these structures that serve as the physical mechanism for maintaining turbulence under supercritically stable stratification.

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Qiu, Jinxing, Zhengying Li, Cuixiang Pei, and Guoqiang Luo. "Simulation of Layer Thickness Measurement in Thin Multi-Layered Material by Variable-Focus Laser Ultrasonic Testing." Sensors 23, no. 2 (January 7, 2023): 694. http://dx.doi.org/10.3390/s23020694.

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Thin multi-layered materials are widely used in key structures of many high technology industries. To ensure the quality and safety of structures, layer thickness measurement by non-destructive testing (NDT) techniques is essential. In this paper, a novel approach for the measurement of each layer’s thickness in thin multi-layered material is proposed by using ring-shaped laser generated focused ultrasonic bulk waves. The proposed method uses a ring-shaped laser with a variable radius to generate shear waves with variable focus inside the structure. By analyzing the signal characteristics at the ring center when the laser radius varies from zero to maximum, the direct measurement of layer thickness can be realized, considering that only when the focal depth and the layer thickness satisfy the specific relationship, the reflected shear waves converge and form a peak at the ring center. This straightforward approach can increase the pulse-echo SNR and prevent the processing of aliasing signals, and therefore provides higher efficiency and accuracy for the layer thickness measurement. In order to investigate the feasibility of this method, finite element simulations were conducted to simulate the ring-shaped laser generated ultrasonic waves in multi-layered structure in detail. Following the principle of the proposed method, the layer thickness of a bi-layer and 3-layer structure were respectively measured using simulation data. The results confirm that the proposed method can accurately and efficiently measure the layer thickness of thin multi-layered material.

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NAGAO, TATSUYA, HIROYUKI MORI, and FUMIKO YONEZAWA. "A GINZBURG-LANDAU THEORY FOR CRITICAL TEMPERATURE OF LAYERED HIGH-Tc SUPERCONDUCTORS." Modern Physics Letters B 03, no. 18 (December 1989): 1393–400. http://dx.doi.org/10.1142/s0217984989002090.

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Using a phenomenological model for layered superconductors, we derive a formalism for the critical temperature T c in terms of the layer numbers. We show that T c of a system of n identical layers is the same as that of a single layer for all values of n. In a periodic layered structure composed of two kinds of layers, T c increases monotonically with the number of higher-T c layers. When the carrier number depends on structure, T c shows a behavior consistent with the experimental data on some high-T c superconductors such as Tl and Bi families. We make a suggestion to achieve a higher T c .

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Brady, Alexander, Weiwei Sun, Jessica L. Durham, Esther S. Takeuchi, Kenneth J. Takeuchi, Amy C. Marschilok, Michael Naguib, Lukas Vlcek, and Hsiu-Wen Wang. "Stacking faults in layered electrode materials: developments in structure solutions for diffraction data." Acta Crystallographica Section A Foundations and Advances 75, a1 (July 20, 2019): a246. http://dx.doi.org/10.1107/s0108767319097587.

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Popkov, A., E. Gabdrakhimova, Z. Sharafieva, and D. Isakov. "Structure of nanostructured layered double hydroxides according to x-ray diffraction analysis data." IOP Conference Series: Earth and Environmental Science 516 (June 18, 2020): 012044. http://dx.doi.org/10.1088/1755-1315/516/1/012044.

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Gorkusha, Aleksandr S., Sergey V. Tsybulya, Svetlana V. Cherepanova, Evgeny Y. Gerasimov, and Svetlana N. Pavlova. "Nonstoichiometry Defects in Double Oxides of the A2BO4-Type." Materials 15, no. 21 (October 31, 2022): 7642. http://dx.doi.org/10.3390/ma15217642.

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Double oxides with the structure of the Ruddlesden–Popper (R-P) layered perovskite An+1BnO3n+1 attract attention as materials for various electrochemical devices, selective oxygen-permeable ceramic membranes, and catalytic oxidative reactions. In particular, Sr2TiO4 layered perovskite is considered a promising catalyst in the oxidative coupling of methane. Our high-resolution transmission electron microscopy (HRTEM) studies of Sr2TiO4 samples synthesized using various methods have shown that their structure often contains planar defects disturbing the periodicity of layer alternation. This is due to the crystal-chemical features of the R-P layered perovskite-like oxides whose structure is formed by n consecutive layers of perovskite (ABO3)n in alternating with layers of rock-salt type (AO) in various ways along the c crystallographic direction. Planar defects can arise due to a periodicity violation of the layers alternation that also leads to a violation of the synthesized phase stoichiometry. In the present work, a crystallochemical analysis of the possible structure of planar defects is carried out, structures containing defects are modeled, and the effect of such defects on the X-ray diffraction patterns of oxides of the A2BO4 type using Sr2TiO4 is established as an example. For the calculations, we used the method of constructing probabilistic models of one-dimensionally disordered structures. For the first time, the features of diffraction were established, and an approach was demonstrated for determining the concentration of layer alternation defects applicable to layered perovskite-like oxides of the A2BO4 type of any chemical composition. A relation has been established between the concentration of planar defects and the real chemical composition (nonstoichiometry) of the Sr2TiO4 phase. The presence of defects leads to the Ti enrichment of particle volume and, consequently, to the enrichment of the surface with Sr. The latter, in turn, according to the data of a number of authors, can serve as an explanation for the catalytic activity of Sr2TiO4 in the oxidative coupling of methane.

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Fenter, Paul, and Changyong Park. "Termination interference along crystal truncation rods of layered crystals." Journal of Applied Crystallography 37, no. 6 (November 11, 2004): 977–87. http://dx.doi.org/10.1107/s0021889804024343.

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A destructive interference observed in high-resolution surface X-ray reflectivity data for diverse systems has been used as a `fingerprint' for determining the terminating plane of layered crystals. It is shown that this phenomenon is (a) general to layered crystal structures, (b) directly sensitive to the crystal termination as a result of phase contrast between layers within the substrate unit cell, and (c) closely related to systematic absences of bulk Bragg diffraction. A simple formalism is derived that relates the location of these destructive interferences to the terminating plane of a crystal using only knowledge of the substrate crystal structure. The factors that control the visibility of this phenomenon for different crystal symmetries and uniformity of the crystal termination are also explored. A special case, where X-ray reflectivity is nominally insensitive to crystal termination, is discussed to show that sensitivity can be obtained through the use of anomalous dispersion or ferroelectric displacements in the substrate lattice. Insight into this phenomenon is obtained by considering the influence of the spatial resolution on an effective electron density and the associated suitability of describing each of the layers in the structure as individual `pseudo-atoms'.

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Szalai, D., and T. Horváth. "Design of multi-layered building structures using BIM method." IOP Conference Series: Materials Science and Engineering 1218, no. 1 (January 1, 2022): 012055. http://dx.doi.org/10.1088/1757-899x/1218/1/012055.

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Abstract Today BIM is an inevitable concept in construction design and while the workflow of consultant designers is mostly influenced to a small extent, new methods require a new kind of communication between them. This research focuses on the workflows of construction designers because their design works have a big impact on many other disciplines. This paper presents an examination about the processing methods of the building structure designers and the use of BIM with a questionnaire survey. In this research, a new way was also introduced to integrate definitions of multi-layered structures (created by construction designers) into the BIM/CAD model itself. The goal was to allow the data in the layer structure documents to be automatically linked to the model, and make it possible for all collaborators to continue working with the data separately. This paper proofs that this automated workflow greatly increases efficiency, accuracy and reduces human errors. ArchiCAD and Excel were used as our development framework: former one to create CAD/BIM models, latter one to handle the database of multi-layered structures. Individual codes were used to identify each unit of the layer structure and link them to the model itself. This way, it is not necessary to manually add the data to the elements, but the material properties can be read automatically into the model and the quantities can be measured. Similar scale, size, and complexity buildings were selected as a test environment where the ordinary and the new method were used in parallel throughout the design process. This provided a good comparison and demonstrated the effectiveness of database-based design. With the new approach, time required for first-round quantification was reduced by 41% and the time of a repeated quantification due to modifications was reduced by 56%, in average.

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Gao, Xing, Guo You Gan, Li Hui Wang, Ji Kang Yan, Jian Hong Yi, Jing Hong Du, and Jia Min Zhang. "La Doped Layered Structure Low-Voltage ZnO Varistor." Key Engineering Materials 512-515 (June 2012): 1263–67. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.1263.

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A novel fabricated technique, by feeding two sets of different ZnO formulations powder in a die by parts, molded only once to produce layered structure(including layer A and layer B) low-voltage ZnO varistor. The samples are examined by using energy dispersive X-ray spectroscopy (EDS), electron probe microanalysis (EPMA), scanning electron microscope (SEM) and DC electrical measurements. EDS and EPMA data indicate that doped elements only exists in layer A, The results of SEM indicate that secondary phases are formed at grain boundaries in layer A, not found in layer B. It is found that the electrical properties of low-voltage varistor are improved without reducing thickness and changing energy absorption capabilities. The higher nonlinearity coefficients, lower breakdown fields and leakage currents of layered structure low-voltage ZnO varistor, as compared to those of ZnO varistor fabricated from the conventional route. The improved current-voltage properties are attributed to the band structure difference in both sides grains, due to the different ion concentration and species in both sides of grain boundary. Layered structure varistor also has more simpler prepared technology than multilayer chip varistor.

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Tarakina, Nadezda V., Tatiana A. Denisova, Yana V. Baklanova, Lidia G. Maksimova, Vladimir G. Zubkov, and Reinhard B. Neder. "Defect Crystal Structure of Low Temperature Modifications of Li₂MO₃ (M=Ti, Sn) and Related Hydroxides." Advances in Science and Technology 63 (October 2010): 352–57. http://dx.doi.org/10.4028/www.scientific.net/ast.63.352.

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Crystal structures of Li2MO3 (M=Sn, Ti) and TiO(OH)2 have been studied in detail and refined using X-ray powder diffraction data. All compounds posses a high concentration of defects in the structure. The crystal structures of the Li2MO3 salts obtained at 700°C reveal stacking faults of LiM2 metal layers, which leads to the appearance of short-range order in three possible space groups: C2/c, C2/m, P3112. The possibility to stabilize this imperfect state increases the mobility of the Li+ ions in the Li2TiO3 structure and allows the complete exchange of lithium by hydrogen in acid water solutions with formation of TiO(OH)2. The crystal structure of TiO(OH)2 belongs to the layered double hydroxide structure type with the 3R1 sequence of oxygen layers and can be described as a stacking of charge-neutral metal oxyhydroxide slabs [(OH)2OTi2O(OH)2].

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Quintana, MC, and MP Frontini. "Development of the layered structure in a double-gated glass fiber-reinforced polypropylene injection molding: Experimental and simulated results." Journal of Reinforced Plastics and Composites 37, no. 14 (April 26, 2018): 945–59. http://dx.doi.org/10.1177/0731684418770528.

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The present study aims to experimentally validate numerical simulation of fiber orientation distribution performed by molding simulation software Moldex3D in a double-gated injection-molded glass fiber-filled (40 wt%) polypropylene box, by making a detailed comparison of predicted and experimentally measured fiber orientation distribution data. The modeling approach evaluated in this work consists in the implementation of the Folgar–Tucker rotary diffusion model with the invariant-based optimal fitting closure approximation for the fourth-order orientation tensor. The specimen used has a weld line in the center and sharp corners. This investigation characterizes in detail the development of the through-thickness layered structure at distinctive locations of the specimen. The sensitivity of fiber orientation distribution and the layered structure to changes upon injection time and melt temperature is also evaluated. The boxes display the typical layered laminate structure, with fibers aligned in the main flow direction near the walls (shell layer) and less oriented in the middle plane (core layer). The boxes injected at the lowest melt temperature display an additional skin layer. Unfortunately, simulation fails in predicting the five layers structure developed under these latter conditions. The grade of fiber orientation is deemed to be independent of process parameters but not the layered structure.

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Liu, Xiao-Xuan, Cheng-Xin Wang, Shu-Ming Luo, and Jin-Xiao Mi. "The layered monodiphosphate Li9Ga3(P2O7)3(PO4)2 refined from X-ray powder data." Acta Crystallographica Section E Structure Reports Online 62, no. 5 (April 11, 2006): i112—i113. http://dx.doi.org/10.1107/s1600536806012426.

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Nonalithium trigallium(III) tris[pyrophosphate(V)] diphosphate(V), Li9Ga3(P2O7)3(PO4)2, has been synthesized by a hydrothermal method and its crystal structure solved from X-ray powder diffraction data using Rietveld analysis. The structure is based on separate layers parallel to (001), consisting of GaO6 octahedra that share corners with PO4 tetrahedra and P2O7 groups. The lithium ions are located in the interstitial space.

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Di, Jinhong, Pengkun Yang, Chunyan Wang, and Lichao Yan. "Layered Lossless Compression Method of Massive Fault Recording Data." International Journal of Circuits, Systems and Signal Processing 16 (January 3, 2022): 17–25. http://dx.doi.org/10.46300/9106.2022.16.3.

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In order to overcome the problems of large error and low precision in traditional power fault record data compression, a new layered lossless compression method for massive fault record data is proposed in this paper. The algorithm applies LZW (Lempel Ziv Welch) algorithm, analyzes the LZW algorithm and existing problems, and improves the LZW algorithm. Use the index value of the dictionary to replace the input string sequence, and dynamically add unknown strings to the dictionary. The parallel search method is to divide the dictionary into several small dictionaries with different bit widths to realize the parallel search of the dictionary. According to the compression and decompression of LZW, the optimal compression effect of LZW algorithm hardware is obtained. The multi tree structure of the improved LZW algorithm is used to construct the dictionary, and the multi character parallel search method is used to query the dictionary. The multi character parallel search method is used to query the dictionary globally. At the same time, the dictionary size and update strategy of LZW algorithm are analyzed, and the optimization parameters are designed to construct and update the dictionary. Through the calculation of lossless dictionary compression, the hierarchical lossless compression of large-scale fault record data is completed. Select the optimal parameters, design the dictionary size and update strategy, and complete the lossless compression of recorded data. The experimental results show that compared with the traditional compression method, under this compression method, the mean square error percentage is effectively reduced, and the compression error and compression rate are eliminated, so as to ensure the integrity of fault record data, achieve the compression effect in a short time, and achieve the expected goal.

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Fetisov, Y. K., V. M. Petrov, and G. Srinivasan. "Inverse magnetoelectric effects in a ferromagnetic–piezoelectric layered structure." Journal of Materials Research 22, no. 8 (August 2007): 2074–80. http://dx.doi.org/10.1557/jmr.2007.0262.

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Measurements of inverse magnetoelectric (ME) effects in lead zirconate titanate (PZT)–Ni–PZT trilayers are reported. Traditional ME measurements involve the electrical response of a composite subjected to an alternating current (ac) magnetic field. In the case of an “inverse ME effect,” one measures the variation in the magnetic induction due to an external ac electric field applied to PZT. A pickup coil wound around the sample is used to measure the ME voltage due to the change in the magnetic induction in Ni. The measured static magnetic-field dependence of ME voltage has been attributed to the variation in the piezomagnetic coefficient for Ni. The frequency dependence of the ME voltage shows a resonance character due to radial acoustic modes in PZT. Theoretical estimates of ME susceptibility are in excellent agreement with values determined from data on induced voltage.

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Bursik, Marcus, Qingyuan Yang, Adele Bear-Crozier, Michael Pavolonis, and Andrew Tupper. "The Development of Volcanic Ash Cloud Layers over Hours to Days Due to Atmospheric Turbulence Layering." Atmosphere 12, no. 2 (February 23, 2021): 285. http://dx.doi.org/10.3390/atmos12020285.

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Volcanic ash clouds often become multilayered and thin with distance from the vent. We explore one mechanism for the development of this layered structure. We review data on the characteristics of turbulence layering in the free atmosphere, as well as examples of observations of layered clouds both near-vent and distally. We then explore dispersion models that explicitly use the observed layered structure of atmospheric turbulence. The results suggest that the alternation of turbulent and quiescent atmospheric layers provides one mechanism for the development of multilayered ash clouds by modulating vertical particle motion. The largest particles, generally μ>100 μm, are little affected by turbulence. For particles in which both settling and turbulent diffusion are important to vertical motion, mostly in the range of 10–100 μμm, the greater turbulence intensity and more rapid turbulent diffusion in some layers causes these particles to spend greater time in the more turbulent layers, leading to a layering of concentration. The results may have important implications for ash cloud forecasting and aviation safety.

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Kaduk, James A. "Crystal structure of strontium hydrogen citrate monohydrate, Sr(HC6H5O7)(H2O)." Powder Diffraction 36, no. 2 (March 16, 2021): 120–28. http://dx.doi.org/10.1017/s0885715621000166.

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The crystal structure of strontium hydrogen citrate monohydrate has been solved using laboratory X-ray powder diffraction data, refined using both laboratory and synchrotron data, and optimized using density functional techniques. Strontium hydrogen citrate monohydrate crystallizes in space group C2/c (#15) with a = 25.15601(17), b = 10.90724(6), c = 6.37341(4) Å, β = 91.9846(6)°, V = 1747.704(12) Å3, and Z = 8. The Sr coordination and the hydrogen bonding result in a layered structure. The SrO8 coordination polyhedra share edges to form corrugated layers parallel to the bc-plane. Hydrogen bonds between the carboxylic acid groups and water molecules link the layers. Intermolecular hydroxyl–carboxyl hydrogen bonds also link the layers in a ring pattern with a graph set symbol R2,2(12). After storage for 2 years, partial re-crystallization occurred, to an as-yet unknown compound with a triclinic unit cell.

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Chen, Genmeng, Janusz Peron, and Luis Canales. "Rapid VSP-CDP mapping of 3-D VSP data." GEOPHYSICS 65, no. 5 (September 2000): 1631–40. http://dx.doi.org/10.1190/1.1444851.

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Vertical seismic profiling‐common depth point (VSPCDP) mapping with rapid ray tracing in a horizontally layered velocity model is used to create 3-D image volumes using Blackfoot and Oseberg 3-D vertical seismic profiling (VSP) data. The ray‐tracing algorithm uses Fermat’s principle and is specially programmed for the layered model. The algorithm is about ten times faster than either a 3-D VSP-CDP mapping program with an eikonal traveltime computation method or a 3-D VSP Kirchhoff migration program. The mapping method automatically separates the image zone from the nonimage zone within the 3-D image volume. The Oseberg data example shows that the lateral extent of the image zone created by the 3D VSP-CDP mapping is larger than that created by 3-D VSP Kirchhoff migration. The same sample result also provides high‐frequency events at target zones. We include an analysis of the imaging error induced from using a horizontally layered model for the Oseberg data, indicating that the method is reliable in the presence of gently dipping structure.

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Lo Turco, M., M. Calvano, and E. C. Giovannini. "DATA MODELING FOR MUSEUM COLLECTIONS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W9 (January 31, 2019): 433–40. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w9-433-2019.

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Abstract. The relationship between cultural heritage, digital technologies and visual models involves an increasingly wide area of research, oriented towards the renewal of archives and museums for the preservation and promotion of culture. Recent research activities are the result of the progressive strengthening of digital technologies and the needs of a new generation of “digital” users, which requires museums to update their means of communication using Semantic Web languages and technologies shaped by a social conceptualization of a graph-based representation of information.The growth of several digitized heritage collections increases the necessity of proper methodologies to develop a structured system able to access to these collections and the large amount of data, metadata and paradata related to the digitized objects in a structured and organized way, defining a set of collection information models (CIM), that considers not only the digitizing process but also the data collection process, layered by an Upper Ontology level structure, based on CIDOC-CRM.

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Krysztofiak, Katarzyna, Kamila Ciężar, and Mikołaj Kościński. "Raman Imaging of Layered Soft Contact Lenses." Journal of Applied Biomaterials & Functional Materials 15, no. 2 (April 2017): 149–52. http://dx.doi.org/10.5301/jabfm.5000329.

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Background Daily disposable contact lenses are gaining in popularity among practitioners and wearers for the improved ocular health and subjective outcomes they offer. Recently a novel daily disposable contact lens material with water gradient technology was introduced. Delefilcon A lenses consist of a 33% water content silicone hydrogel core and an outer hydrogel layer which is totally free of silicone and contains 80% water. Methods The aim of the present study was to confirm the layered structure of delefilcon A contact lenses. Thickness of hydrogel coating on the silicone hydrogel core was assessed using Raman spectroscopy. To investigate the layered structure of the material, depth spectra of the lenses were recorded. Results The results obtained suggest that at about 6 μm a boundary between the hydrogel layer and silicone hydrogel core exists, which is in good agreement with the manufacturer's data. Conclusions Data collected in this experiment confirm a water gradient at the delefilcon A lens surface.

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Zhang, Yong‐xia. "Aeromagnetic anomalies and perspective oil traps in China." GEOPHYSICS 59, no. 10 (October 1994): 1492–99. http://dx.doi.org/10.1190/1.1443539.

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Based on analyses of aeromagnetic data from known oil and gas fields in China, aeromagnetic anomalies have been classified according to their genesis into three types: (1) structure‐associated anomalies related to volcanic rock, (2) anomalies related to magnetic basement fault blocks, and (3) structure‐associated anomalies related to weakly magnetic sedimentary strata. The most successful applications of aeromagnetic data for locating favorable oil and gas structures are in the following kinds of areas: (1) areas where basement fault blocks of inhomogeneous lithology and magnetization are developed; (2) areas of weakly magnetic layered strata with a considerable thickness, either effusive or clastic deposits; and (3) areas where magnetic layers have undergone tectonic deformation with faulting and dip angles larger than 30 degrees. For reliable detection of such structures in sedimentary rocks and associated oil and gas traps, an integrated interpretation of geological and geophysical data is necessary.

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Basheer, Mohammed Abdul, Vagmare Gangadhar, Guduru Prasad, Gobburu Subramanya Kumar, and Nandi Venkata Prasad. "Electrical and Raman Spectroscopic Studies on Aurivillius Layered-Pervoskite Ceramics." Advanced Materials Research 1154 (June 2019): 80–90. http://dx.doi.org/10.4028/www.scientific.net/amr.1154.80.

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Double rare-earth (La; Sm/Gd) substituted Aurivillius family of Bismuth Layered Structured Ferroelectrics (BLSF) namely Bi2.6Sm0.2La0.2TiNbO9 (BSLT; sample-A), Bi2.6Gd0.2La0.2TiNbO9 (BGLT; sample-B), single phase ceramics were prepared by solid state route. In addition, intergrowth (x BSLT - (1-x) BGLT, where x=0.49; sample-C) and solid solution (BSLTx - BGLTy; where x + y=0.4; sample-D) materials were prepared. Dielectric, ferroelectric and Raman spectroscopic properties were studied on the said above materials. The X-ray diffraction analysis and Raman spectra revealed well-formation of stable structure. Though, the sample-C and sample-D have lower coercive field, compared to the sample-A and sample-B, but they exhibited sharp hysterisis loop. Therefore the instrinsic defects of sample-D inhabits more sensitivity towards the ferroelectric behaviour. The results were corroborated to the impedance and dielectrical data. The results were consistent with the SEM micrographs and complex impedance plots. An attempt is made to understand the effect of rare-earth ions on A-site of layered-pervoskite structure, defined as: (Bi2O2)2+(An-1BnO3n+1)2-.The term n represents number of pervoskite blocks interleaved with the bismuth oxide layers.

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Kumagai, Takuhiro, Naoki To, Armandas Balčytis, Gediminas Seniutinas, Saulius Juodkazis, and Yoshiaki Nishijima. "Kirchhoff’s Thermal Radiation from Lithography-Free Black Metals." Micromachines 11, no. 9 (August 30, 2020): 824. http://dx.doi.org/10.3390/mi11090824.

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Lithography-free black metals composed of a nano-layered stack of materials are attractive not only due to their optical properties but also by virtue of fabrication simplicity and the cost reduction of devices based on such structures. We demonstrate multi-layer black metal layered structures with engineered electromagnetic absorption in the mid-infrared (MIR) wavelength range. Characterization of thin SiO2 and Si films sandwiched between two Au layers by way of experimental electromagnetic radiation absorption and thermal radiation emission measurements as well as finite difference time domain (FDTD) numerical simulations is presented. Comparison of experimental and simulation data derived optical properties of multi-layer black metals provide guidelines for absorber/emitter structure design and potential applications. In addition, relatively simple lithography-free multi-layer structures are shown to exhibit absorber/emitter performance that is on par with what is reported in the literature for considerably more elaborate nano/micro-scale patterned metasurfaces.

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Veesa, Joshua Deepak, and Hamid Dehghani. "Hyper-spectral Recovery of Cerebral and Extra-Cerebral Tissue Properties Using Continuous Wave Near-Infrared Spectroscopic Data." Applied Sciences 9, no. 14 (July 16, 2019): 2836. http://dx.doi.org/10.3390/app9142836.

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Near-infrared spectroscopy (NIRS) is widely used as a non-invasive method to monitor the hemodynamics of biological tissue. A common approach of NIRS relies on continuous wave (CW) methodology, i.e. utilizing intensity-only measurements, and, in general, assumes homogeneity in the optical properties of the biological tissue. However, in monitoring cerebral hemodynamics within humans, this assumption is not valid due to complex layered structure of the head. The NIRS signal that contains information about cerebral blood hemoglobin levels is also contaminated with extra-cerebral tissue hemodynamics, and any recovery method based on such a priori homogenous approximation would lead to erroneous results. In this work, utilization of hyper-spectral intensity only measurements (i.e., CW) at multiple distances are presented and are shown to recover two-layered tissue properties along with the thickness of top layer, using an analytical solution for a two-layered semi-infinite geometry. It is demonstrated that the recovery of tissue oxygenation index (TOI) of both layers can be achieved with an error of 4.4%, with the recovered tissue thickness of 4% error. When the data is measured on a complex tissue such as the human head, it is shown that the semi-infinite recovery model can lead to uncertain results, whereas, when using an appropriate model accounting for the tissue-boundary structure, the tissue oxygenation levels are recovered with an error of 4.2%, and the extra-cerebral tissue thickness with an error of 11.8%. The algorithm is finally used together with human subject data, demonstrating robustness in application and repeatability in the recovered parameters that adhere well to expected published parameters.

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Racherla, Gopal, Sridhar Radhakrishnan, and B. John Oommen. "Enhanced layered segment trees: a pragmatic data structure for real-time processing of geometric objects." Pattern Recognition 35, no. 10 (October 2002): 2303–9. http://dx.doi.org/10.1016/s0031-3203(01)00202-3.

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Mahmoudkhani, Amir H., Vratislav Langer, and Lubomir Smrcok. "Layered strontium phenylphosphonate: synthesis, thermal properties and crystal structure from X-ray powder diffraction data." Solid State Sciences 4, no. 6 (May 2002): 873–78. http://dx.doi.org/10.1016/s1293-2558(02)01294-3.

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Pashchenko, E. A. "Mechanochemical Changes in the Structure of Layered Silicates according to 27Al and 29Si NMR Data." Russian Journal of Applied Chemistry 78, no. 2 (February 2005): 339. http://dx.doi.org/10.1007/s11167-005-0288-x.

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42

Charfeddine, Mohamed Ali, Jean-Francis Bloch, and Patrice Mangin. "Mercury porosimetry and x-ray microtomography for 3-dimensional characterization of multilayered paper: Nanofibrillated cellulose, thermomechanical pulp, and a layered structure involving both." BioResources 14, no. 2 (February 13, 2019): 2642–50. http://dx.doi.org/10.15376/biores.14.2.2642-2650.

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Mercury intrusion porosimetry (MIP) is an inexpensive and common technique to characterize porous structures like paper. One major limitation of MIP is the lack of information about the arrangement of pores in the structure, information that is particularly relevant for multilayer structures such as thickness-structured paper. In this article, results from Synchrotron X-ray 3D microtomography are combined with MIP data to provide in-depth and improved information about the structures.

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Elloh, V. W., Soni Mishra, A. Yaya, and Abhishek Kumar Mishra. "First-principles calculations on structure and electronic properties of α-zirconium hydrogen phosphate." MRS Advances 4, no. 50 (2019): 2699–707. http://dx.doi.org/10.1557/adv.2019.309.

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AbstractLayered zirconium hydrogen phosphate intercalation compounds can be easily tuned, leading to potential applications in many fields, specifically by introducing them in different polymeric composites as nanofillers. Employing first-principles density functional theory based calculations, we have investigated ground state electronic structure properties of α-zirconium hydrogen phosphate (α-ZrP). We discuss the structure and electronic band structure, where projected density of states calculations have been discussed to understand the different atomic orbitals contributions to electronic bands. ZrP has numerous properties of interest for use in many semiconductor device structures, specifically, layered zirconium hydrogen phosphate has substantial promise for both optical devices and for high power electronics due to its large direct band gap. Our structural calculations suggest that layered zirconium hydrogen phosphate exhibits monoclinic structure. The calculated structural parameters and band gap are in good agreement with available experimental data.

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Katsumta, Tetsuhiro, Naofumi Takami, Daisuke Mori, and Yoshiyuki Inaguma. "Synthesis and crystal structure of Sr2MnGaO5-dFx, layered oxyfluorides." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1108. http://dx.doi.org/10.1107/s2053273314088913.

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Sr2MnGaO5 brownmillerite has an interesting structure. In this compound, MnO6 octahedra and GaO4 tetrahedra are ordered along c-axis. The MnO6 octahedra are deformed due to Jahn-Teller effect with four short equatorial Mn-O distances and two long apical one. Oxygen vacancies in the GaO layer provide distorted tetrahedral coordination for the Ga cation. The oxide and/or fluoride ions are introduced into the vacancies in GaO layer. The synthesis of Sr2MnGaO4.78F1.22 using XeF2 as a fluorinating agent is reported, while the small amount SrF2 impurity is contained[1]. On the other hand, low temperature fluorination using polyvinylidenefluoride (PVDF) is powerful method for the synthesis of oxyfluoides from brownmillerite[2]. In this study, we synthesize the Sr2MnGaO5-dFx (x=0.5, 1.0, 1.5, 2.0) using PVDF and investigate the variation of crystal structure with x. Sr2MnGaO5 brownmillerites were prepared sold state reaction method. Starting materials were SrCO3, Mn2O3 and Ga2O3. The mixture was heated twice in Ar at 13000C for 72h. For the preparation of Sr2MnGaO5-dFx (x=0.5, 1.0, 1.5, 2.0), stoichiometric amounts of Sr2MnGaO5 brownmillerite and PVDF were ground and the mixture were heated in N2 at 4000C for 8h. And then, the as prepared materials were subsequently heated in O2 at 4000C for 8h. The Sr2MnGaO5-dFx were obtained without impurities. As shown in Fig., the orthorhombic distortion reduced with the increase in x. The X-ray diffraction data of Sr2MnGaO5-dF1.0 could be refined on the structure model belonging the space group Icmm. the bond valence sum of Ga3+ calculated from Ga-O bond length indicates that the fluoride ions are introduced into GaO layer preferentially. The measurements of magnetic properties for Sr2MnGaO5-dFx are in progress.

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Duits, M. H. G., R. P. May, and C. G. de Kruif. "The internal structure of layered colloidal particles determined with SANS." Journal of Applied Crystallography 23, no. 5 (October 1, 1990): 366–73. http://dx.doi.org/10.1107/s0021889890005027.

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Small-angle neutron scattering measurements at various contrasts were performed on dilute colloidal silica dispersions in order to resolve the internal structure of the particles. The particles were prepared by outgrowth of a commercially available silica core, followed by an esterification of the surface silanol groups with stearyl alcohol. Variation of the scattering contrast was achieved by using mixtures of 1H12- and 2H12-cyclohexane as dispersing medium. The scattering data were interpreted as originating from a polydisperse system of spherical three-layer particles. Model parameters were optimized sequentially, applying an increasing number of constraints. Good agreement between experimental and calculated scattering curves is obtained, even at higher K values and low contrasts. In comparison with other particles in the same size range, these silica particles represent a very suitable model system for small-angle scattering experiments at higher volume fractions.

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Wang, Xiang Qiu, Zhi Guo Zhou, and Yu Hong Zhang. "Non-Linear FEM Analysis for the Layered Rock-Mass Tunnel Based on the Twin Shear Strength Criterion." Advanced Materials Research 168-170 (December 2010): 152–55. http://dx.doi.org/10.4028/www.scientific.net/amr.168-170.152.

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According to the geotechnical conditions, A FEM model has been established to analyse the mechanical characteristics of the highway tunnel in the layered rock mass. In this model the layered rock mass and the soften joint are simulated by the transversal isotropic material, the interfaces between layers are simulated by the element of rotational Goodman interface, but the interface between the lining structure and surrounding mass is proposed to simulate by an interface element with thickness, and the supporting of tunnel is simulated by the straight beam element. In the meantime, based on the twin shear strength criterion, the mechanical characteristics of rock, the stiff matrix of element for the layered rock mass, soften joint and interface have been discussed. The analytical model has been demonstrated by comparing the results of layered surrounding rock-mass FEM with the test data in situ.

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Lu, Xilin, Peizhen Li, Bo Chen, and Yueqing Chen. "Computer simulation of the dynamic layered soilpilestructure interaction system." Canadian Geotechnical Journal 42, no. 3 (June 1, 2005): 742–51. http://dx.doi.org/10.1139/t05-016.

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A three-dimensional finite element analysis of the soilpilestructure interaction system is presented in this paper. The analysis is based on data from shaking table model tests made in the State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, China. The general finite element program ANSYS is used in the analysis. The surface-to-surface contact element is taken into consideration for the nonlinearity state of the soilpile interface, and an equivalent linear model is used for soil behavior. A comparison of the results of the finite element analysis with the data from the shaking table tests is used to validate the computational model. Furthermore, the reliability of the test result is also verified by the simulation analysis. It shows that separation, closing, and sliding exist between the pile foundation and the soil. The distribution of the amplitude of strains in the pile, the amplitude of contact pressure, and the amplitude of sliding at the soilpile interface are also discussed in detail in this paper.Key words: soilpilestructure interaction, shaking table model test, computer simulation, ANSYS program.

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Krainyukov, Alexander, and Valery Kutev. "Improving of Data Processing Effectiveness for Pavement Structural Evaluation Using Subsurface Radar Probing." Transport and Telecommunication Journal 14, no. 2 (June 1, 2013): 143–54. http://dx.doi.org/10.2478/ttj-2013-0012.

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Problems of the data processing improving for pavement structure evaluation with help of subsurface radar probing are discussed. Iterative procedure to solve the inverse problem in frequency domain is used on the base of the genetic algorithm. For improving of data processing effectiveness it is proposed to use a modified genetic algorithm with adaptation of search range of pavement parameters. The results of reconstruction of electro-physical characteristics for model of five-layered pavement structure are presented.

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Hsu, Chin-Yin, Teng-Chun Yang, Tung-Lin Wu, Ke-Chang Hung, and Jyh-Horng Wu. "Effects of a layered structure on the physicomechanical properties and extended creep behavior of bamboo-polypropylene composites (BPCs) determined by the stepped isostress method." Holzforschung 72, no. 7 (July 26, 2018): 589–97. http://dx.doi.org/10.1515/hf-2017-0165.

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AbstractA layered bamboo-plastic composite (BPC) consisting of bamboo (Phyllostachys makinoi) particles and polypropylene was investigated. The influence of the layering conditions, including the thickness and bamboo content in various layers, was the focus in terms of the physicomechanical and creep properties of the BPCs. The results showed that a three-layered BPC (BPC3L) with a 1:3:1 thickness ratio and with top/bottom layer containing 40% bamboo exhibited the best specific flexural properties. An accelerated creep test approach was applied, known as the short-term stepped isostress method (SSM), to predict the long-term creep behavior of BPC3L. The results indicated that the creep master curves, which are constructed from different SSM testing parameters, agree well with the long-term experimental creep data and that the creep resistance of homogeneous single-layered BPC was better than that of BPC3L.

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Ding, Yu, Haimin Guo, Moujie Li, Changrong Lin, and Xuyang Guo. "Research on Identification of Petroliferous Unit Based on Seismic Data Structure Characteristics." Open Civil Engineering Journal 9, no. 1 (October 7, 2015): 783–88. http://dx.doi.org/10.2174/1874149501509010783.

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The identification and classification of petroliferous unit is the key to the success in the exploration for oil-gas fields with geophysical knowledge that are the main means and ways to reduce exploration risk and improve exploration efficiency. In this paper, it analyzes geophysical response characteristics under conditions of gas, oil and water through the establishment of horizontal layered medium model. Then it extracts and analyzes seismic abnormal characteristics of the data structure combining the method of grey system theory based on the experiment, which are considered as an important reference for further objectively identifying petroliferous unit and the exploration of oil-gas fields in the practical application with comparison and analysis.

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Journal articles on the topic 'Layered Data Structure'

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