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... An experimental study has been carried out to describe the evolution of the failure load relative to the maximum misalignment angle of curved carbon–epoxy laminates with out-of-plane wrinkle defects for a large range of misalignments. L-angle specimens with different levels of fibre wrinkling were manufactured and tested in four-point bending tests. Digital Image Correlation (DIC) and infrared the ...
... This study investigates the effectiveness of hybrid fibers (steel and macro-synthetic) on the shear behavior of prestressed concrete beams. The hybrid fiber combination was selected to avoid workability issues at high volume dosages and ensure effective crack arresting over the crack opening range. Fracture studies included testing notched concrete prisms to identify the role of hybrid fibers in t ...
... Photoacoustic (PA) imaging technology, a three-dimensional hybrid imaging modality that integrates the advantage of optical and acoustic imaging, has great application prospects in molecular imaging due to its high imaging depth and resolution. To endow PA imaging with the ability for real-time molecular visualization and precise biomedical diagnosis, numerous activatable molecular PA probes which ...
digitalimages, etc ; cameras; computer science; lighting; Show all 4 Subjects
Abstract:
... Mobile robots lack a driver or a pilot and, thus, should be able to detect obstacles autonomously. This paper reviews various image-based obstacle detection techniques employed by unmanned vehicles such as Unmanned Surface Vehicles (USVs), Unmanned Aerial Vehicles (UAVs), and Micro Aerial Vehicles (MAVs). More than 110 papers from 23 high-impact computer science journals, which were published over ...
digitalimages, etc ; carbon; delamination; polymers; ultrasonics; Show all 5 Subjects
Abstract:
... A simple and efficient non-destructive testing method is presented to quantify translaminar fracture properties in quasi-isotropic [90/45/0/-45]3s T800SC/3900-2B carbon fibre-reinforced polymer laminates subjected to Over-height Compact Tension (OCT) and Compact Compression (CC) fracture tests. The combination of Digital Image Correlation (DIC) with phased-array ultrasonics enables the consistent ...
digitalimages, etc ; cameras; photographs; photography; vibration; Show all 5 Subjects
Abstract:
... When combined with high-speed photography technology, the digital image correlation (DIC) method provides an excellent photographic image processing capability that can be used to convert the evolving full-field surface properties of structures to sets of two-dimensional (2D) or three-dimensional (3D) coordinate values. In this study, the applicability of the DIC method and high-speed cameras in u ...
digitalimages, etc ; data collection; standard deviation; Show all 3 Subjects
Abstract:
... The present article shares with the scientific community several image sets used for experimentally validating the noise-induced bias on different Digital Image Correlation (DIC) formulations, as reported in Baldi et al. [1]. These sets are provided with a description of the experimental setup used for image acquisition. The basic idea is to acquire a series of images obtained by rigidly translati ...
digitalimages, etc ; data collection; lidar; photogrammetry; Show all 4 Subjects
Abstract:
... Place recognition is widely used for global localization technology. However, the existing place recognition solutions are limited by the requirement for the same type of sensors to be used in both the localization process and the mapping process. Therefore, the existing heterogeneous 3D map cannot be used for place recognition directly with the existing methods, leading to underutilization of inf ...
digitalimages, etc ; agronomy; algorithms; data collection; greenhouses; Show all 5 Subjects
Abstract:
... Autonomous navigation in greenhouses requires agricultural robots to localize and generate a globally consistent map of surroundings in real-time. However, accurate and robust localization and mapping are still challenging for agricultural robots due to the unstructured, dynamic and GPS-denied environmental conditions. In this study, a state-of-the-art real-time localization and mapping system was ...
digitalimages, etc ; algorithms; cotton; fabrics; user interface; Show all 5 Subjects
Abstract:
... Cotton yarn diameter is an important characteristic that reflects the quality of the yarn to a large extent. In this paper, a new method was proposed to determine the diameter of cotton yarn using digital image processing and artificial neural networks. After processing scanned yarn image, the inputs of ANN were represented by yarn count and the white pixels number of edge detection of processed i ...
digitalimages, etc ; carbon; carbon fibers; deformation; epoxides; temperature; Show all 6 Subjects
Abstract:
... The continuous tow shearing (CTS) process is an advanced tape placement technique with the ability to steer unidirectional prepreg tapes by in-plane shear deformation without the presence of tape buckling, gaps and overlaps. However, the inherent fibre misalignment within the tape can induce fibre waviness during the shearing process, which is further affected by processing parameters such as temp ...
digitalimages, etc ; acoustics; carbon; epoxides; micro-computed tomography; Show all 5 Subjects
Abstract:
... An experimental study was carried out to investigate the effect of material architecture on the damage evolution in carbon/epoxy composites through Overheight Compact Tension (OCT) tests. Four representative lay-ups were designed for both the unidirectional (UD) and woven-based laminates. Interrupted tests were carried out to characterise specimen damage using X-Ray Micro-Computed Tomography. Digi ...
digitalimages, etc ; carbon fibers; deformation; fabrics; polyesters; thermodynamics; Show all 6 Subjects
Abstract:
... The macroscopic response and local deformation mechanisms of a warp stitched heavy-tow unidirectional non-crimp fabric (UD-NCF) was characterized. Quasi-static uniaxial tests captured the fabric in-plane longitudinal, transverse, and shear deformation response where digital image correlation was employed. The fabric bending response was captured through modified cantilever tests. Off-axis extensio ...
digitalimages, etc ; acoustics; case studies; deformation; granite; railroads; Show all 6 Subjects
Abstract:
... Rockburst poses a great threat to the construction safety of deep tunnels under high geostress conditions. Recently, numerous deeply buried tunnels have been constructed in China, especially in the Sichuan–Tibet railway area. In this study, two rockburst experiments (strainbursts and impact-induced rockbursts) were conducted under different initial geostresses using the strainburst experimental ap ...
digitalimages, etc ; carbon; light microscopy; modulus of rupture; Show all 4 Subjects
Abstract:
... Combining the load–displacement curve with the In situ strain field evolution obtained by the digital image correlation (DIC), the flexural behavior and failure mechanism of 2D needle-punched carbon/carbon composites under three-point flexural tests were investigated. The carbon/carbon composites showed a typical pseudoplastic mechanical behavior, and the average flexural strength was 137.0 ± 15.5 ...
digitalimages, etc ; dispersibility; sea level; solutes; unconfined aquifer; Show all 5 Subjects
Abstract:
... Studies of solute transport in unconfined coastal aquifers typically neglect oceanic oscillations and assume a static seaward boundary condition defined by the mean annual sea level. In this paper, an image monitoring method is used to establish the quantitative relationship between the concentration of a colored tracer and the hue value of the image. The digital image was used to determine the tr ...
digitalimages, etc ; Acer rubrum; arborists; bark; deformation; infrastructure; Show all 6 Subjects
Abstract:
... Arborists maintain trees in landscapes where failure can cause damage to infrastructure. Codominant branch unions are considered less stable than lateral branch unions. Previous research has found that unions can be considered codominant when aspect ratio is greater than 0.70 when included bark is present, yet it remains unclear if this threshold is reasonable in the absences of included bark. We ...
digitalimages, etc ; chemistry; color; durability; fluorescence; polymers; spectrometers; Show all 7 Subjects
Abstract:
... The sensitive detection and dynamic monitoring of the structural health of polymers are crucial to increase their quality, reliability, and durability. Although a lot of effort has been devoted to the indication of static damaged and/or healed states of polymers, the simple, sensitive, and real-time monitoring of dynamic damaging–healing processes still remains challenging. In this work, a facile ...
digitalimages, etc ; cellulose; cellulose nanofibers; energy; filtration; mechanical properties; Show all 6 Subjects
Abstract:
... Cellulose nanopaper (CNP) made of cellulose nanofibrils has gained extensive attention in recent years for its lightweight and superior mechanical properties alongside sustainable and green attributes. The mechanical characterization studies on CNP at the moment have generally been limited to tension tests. In fact, thus far there has not been any report on crack initiation and growth behavior, es ...
digitalimages, etc ; Bayesian theory; data collection; models; spatial data; Show all 5 Subjects
Abstract:
... Semantic 3D building models are provided by public authorities and can be used in applications, such as urban planning, simulations, navigation, and many others. Since large-scale 3D models are typically derived from top-view digital surface models (DSM), they can have detailed roof structures but render planes for façade elements. Furthermore, buildings’ underpasses are often unmodeled, which imp ...