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The morphological changes of deep-water channels have an important influence on the distributions of channel sand reservoirs, so it is important to explore the morphological change process of deep-water channel for the exploration and development of deep-water oil and gas. Based on a typical sinuous Quaternary channel (Channel I) in the Taranaki Basin, New Zealand, a variety of seismic interpretation techniques were applied to quantitatively characterize the morphological characteristics of the Channel I, and the relationships between the quantitative parameters and the morphological changes of the Channel I, as well as the controlling factors affecting those morphological changes, were discussed. The results are as follows: (1) in the quantitative analysis, six parameters were selected: the channel depth, width, sinuosity, and aspect ratio (width/depth), the channel swing amplitude (λ) and the channel bend frequency (ω); (2) according to the quantitative morphological parameters of the channel (mainly including three parameters such as channel sinuosity, ω and λ), the Channel I was divided into three types: the low-sinuous channel (LSC), the high-sinuous channel (HSC), the moderate-sinuous channel (MSC). U-shaped channel cross-sections developed in the LSC, V-shaped channel cross-sections developed in the HSC, including inclined-V and symmetric-V cross-sections, and dish-shaped channel cross-sections developed in the MSC; (3) the morphological characteristics of the LSC and MSC were related to their widths and depths, while the morphology of the HSC was greatly affected by the channel width, a change in depth did not affect the HSC morphology; (4) the morphological changes of the Channel I were controlled mainly by the slope gradient, the restricted capacity of the channel and the differential in fluid properties. [ABSTRACT FROM AUTHOR]

Two kind of light scattering measurement methods, i.e. the forward light scattering measurement method and the angular light scattering measurement method, are applied to reconstruct the geometrical morphology of particle fractal aggregates. An improved attractive and repulsive particle swarm optimization algorithm is applied to reconstruct the geometrical structure of fractal aggregates. It has been confirmed to show better convergence properties than the original particle swarm optimization algorithm and the attractive and repulsive particle swarm optimization algorithm. Compared with the forward light scattering measurement method, the angular light scattering measurement method can obtain more accurate and robust results as the distribution of the fitness function value obtained by the angular light scattering measurement method is more satisfactory. Meanwhile, the retrieval accuracy can be improved by increasing the number of measurement angles or the interval between adjacent measurement angles even when the random noises are added. All the conclusions have important guiding significance for the further study of the geometry reconstruction experiment of fractal aggregates. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Heilongjiang University of Science & Technology is the property of Journal of Heilongjiang University of Science & Technology Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of Nanjing University of Aeronautics & Astronautics is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The corresponding relationship between the fracture geometrical morphology of laminar shale and the acoustic emission (AE) power spectrum characteristics was established to further reveal the shale microdamage mechanism. Laboratory Brazilian tests coupled with AE and digital image correlation (DIC) were conducted on black shale disks. The amplitude–time–dominant/second dominant frequency values of AE waveforms from the entire loading process were extracted with the function package PSD in MATLAB. The geometrical morphology of shale disk fracture is the result of a dynamic balance of microcracks, spatial anisotropy, local heterogeneity of the shale specimen, and the stress condition. There is a corresponding relationship between the distribution of dominant/second dominant frequency and shale internal microdamage. Four factors contribute to the shale specimen final failure, including the tearing of the shale matrix induced by local tensile failure (high dominant/second dominant frequency components at approximately 300 kHz), shearing on the bedding layer (middle dominant/second dominant frequency components at approximately 200–250 kHz), opening of the bedding layer induced by the weak structural plane, and friction on the microcrack surface (low dominant/second dominant frequency components at approximately 150 kHz). The fracture mainly controlled by the shale matrix tearing is flexible in profile because it is greatly affected by the competition of microcracks and local natural defects in the process of initiation and propagation. The fracture controlled by the opening of the bedding layer is a straight line with the rough surface and the fracture controlled by the shearing on the bedding layer is a straight line with the smooth surface. Finally, the fracture predominantly controlled by friction on the microcrack surface is generally arched. This work is helpful in providing considerations for depicting the probable fracture planar profile and explaining the microdamage mechanism, allowing for the enhancement of human control when constructing complex underground fracture networks in shale reservoirs. [ABSTRACT FROM AUTHOR]

In this paper, an end-to-end learning framework—RGB enhanced point cloud fusion network (REPF-Net) is designed based on the complementary and enhanced fusion of multi-sensor (camera and lidar) data, aiming to realize the accurate perception of the robot in a random complex environment. In other words, the three-dimensional position and geometric shape of environmental targets can be obtained excellently and the accuracy of target recognition can be improved. Meanwhile, three key problems in 3D perception tasks were solved including, enhancing the fusion point cloud with RGB feature points, achieving effective fusion of heterogeneous data, and enhancing the skeleton information of the target point set. Point-by-point channel attention network (PCA-Net) is proposed to obtain the deep image features. The loss of attention consistent execution (ACE) loss function is proposed to overcome the inconsistencies of localization and classification confidence. Numerous experiments on the KITTI dataset prove that the proposed REPF-Net is superior to the currently common advanced 3D sensing algorithms. [ABSTRACT FROM AUTHOR]

We detected that fishes with elasmoid scale can organize subspecies forms of central scale sclerit. We taked Baikal omul as polymorphic object for study of character of differentiation from this parametr. We detected hexahedral, pentahedral, rectangle, rhomboid and double (two-embryonic) forms of the central sclerit. The percentage composition of types of central sclerit was studied in three major populations. Individuals with pentahedral form of central sclerit are predominate in major omul populations. Scale first year growth characteristics of individuals with different types of central sclerit was studied. We revealed that individuals differ from geometry of central sclerit and also from growth characteristics of first annual ring. However, scale growth of individuals with the same types of central sclerit is conserve in populations. The origin of geometry and nature of geometric forms of scale tissue is under discussion.

Abstract: Biological diversity can be measured using ecological, taxonomic and functional indices, although numerous studies have concluded that organism morphology can be also a source for computing diversity indices. In the present study, we characterized fish morphology using geometric morphology, which included body shape landmarks as well as the morphology of fins, and we computed the correlation among ecological, taxonomic, functional and morphological indices (including a new index defined here called “morphological richness”). Morphological indices were calculated both from abundance data and presence/absence data. To carry out this study, thirteen fish assemblages of two different areas of the Catalan coast (north-western Mediterranean) were analyzed. The data was sampled by commercial fishing vessels using trammel nets. The results clearly indicated that each type of morphological index is related to one dimension of the biodiversity space. Furthermore, we demonstrated that presence/absence data provided the similar results as abundance data when using morphological indices, opening the possibility to analyze the evolution of fish assemblages over time from species checklists collected in experimental surveys from the late XIX century to the present. [Copyright &y& Elsevier]

• Carbon support has a more significant effect on R Local than R Bulk. • Geometrical morphology influences R Bulk via featuring the pore structure in CLs. • Surface chemistry influences R Local via determining the distribution of ionomer. • Developing carbon supports with both high ORR activity and low R O 2 is essential. Carbon support not only promises to dispersedly anchor Pt-based metal nanoparticles but also functions as the critical component of catalyst layers (CLs) in polymer electrolyte membrane fuel cells (PEMFCs). Thus, the geometrical and surface properties of carbon support are believed to impact the mass transport greatly, especially the local oxygen transport in ultra-low Pt PEMFCs. Herein, we explore influences of carbon support on oxygen transport resistance in cathode catalyst layers (CCLs) through combining the limiting current method with a dual-layer CCL design. Results demonstrate that the properties of carbon support have a more significant effect on the local oxygen transport resistance relative to the bulk one. Based on various advanced physicochemical characterizations, it is analyzed that the geometrical morphology of carbon support influences the bulk oxygen transport resistance via featuring the pore structure in the electrode, while the surface functional groups of carbon support influence the local oxygen transport resistance via determining the distribution of ultra-thin ionomer films on the catalyst surface. It is believed that the findings on the interaction between carbon support and cathode mass transport behavior give a critical enlightenment on the design of high performance ultra-low Pt membrane electrode assemblies (MEAs). Both the bulk and local transport resistance are influenced by the properties the carbon supports and a more significant effect on the former relative to the bulk one is observed. Image, graphical abstract [ABSTRACT FROM AUTHOR]