The restriction of the field of view (FOV) enlargement and spatial resolution increase during optical monitoring was investigated. Traditional optical instruments usually have a fixed FOV in one test; thus, they have low accuracy for small samples under large motions/deformations. To improve the spatial resolution in a relatively large FOV of an optical instrument, a multiple-view 3D digital image correlation (3D-DIC) method based on pseudo-overlapped imaging is proposed.
View Article and Find Full Text PDFThe storage and transmission of videos at high spatial resolution remain a great challenge in image-based optical techniques. The uncertainty of digital image correlation (DIC) was assessed following speckle video compression under High Efficiency Video Coding (HEVC/H.265).
View Article and Find Full Text PDFWe propose a novel hybrid FPP-DIC technique to measure an object's shape and deformation in 3D simultaneously by using a single 3CCD color camera, which captures the blue fringe patterns and red fluorescent speckles within the same image. Firstly, red fluorescent speckles were painted on the surface of the specimen. Subsequently, 12 computer-generated blue fringe patterns with a black background were projected onto the surface of the specimen using a DLP projector.
View Article and Find Full Text PDFLamiophlomis rotata is a medicinal plant in Qinghai-Tibet Plateau, in which flavonoid compounds are the major medicinal components. However, it remains unclear how flavonoid metabolism of L. rotata is influenced by soil properties and microbial community.
View Article and Find Full Text PDFTo study the compressive properties of an elastomeric porous cylinder, a 360° 3D digital image correlation (DIC) system is proposed. This compact vibration isolation table system captures different segments of the object from four different angles and fields of view, enabling a comprehensive measurement of the full surface of the object. To increase the stitching quality, a coarse-fine coordinate matching method is presented.
View Article and Find Full Text PDFPerlodinella microlobata Wu, 1938 is rediscovered in Qinghai and Sichuan provinces with a supplementary description in this paper. Another species collected from Qinghai at the same time, Tibetisoperla sclerotica Yan, Chen, Bozdogan & Li, 2022, is partially revised because the adult female belongs to the chloroperlid genus Sweltsa Ricker, 1943.
View Article and Find Full Text PDFJ Plant Physiol
December 2022
Lycium chinense is an important medicinal plant in the northwest of China. Flavonoids are the major pharmacological components of L. chinense fruits.
View Article and Find Full Text PDFFluorescent digital image correlation (DIC) is becoming popular for measuring 3D profiles and deformations in external surfaces. However, the simultaneous monitoring of interior layers is highly challenging due to the penetrability and refraction of light using monochromatic fluorescence. We propose a color fluorescent speckle pattern (CFSP) method for measuring the internal displacement of transparent objects based on multispectral stereo-DIC and refractive index correction.
View Article and Find Full Text PDFCreophilus Leach and Platydracus Thomson are two genera whose members were formerly included in a poorly defined Staphylinus. Both include large-sized rove beetles that can be frequently found in carrion, faeces, and other such rotting materials worldwide. But there are not yet mitochondrial genomes in public databases, which deters scientists from further studies that involve species of these two genera.
View Article and Find Full Text PDFA new leafhopper species, Chinaocerus dentatus Zhang sp. nov., is described and illustrated from Qinghai and Gansu Provinces, China.
View Article and Find Full Text PDFSimultaneous monitoring of overlapped multi-wing structure by stereo-digital image correlation (stereo-DIC) may be used to quantify insect motion and deformation. We propose a dual stereo-DIC system based on multispectral imaging with a polarization RGB camera. Different fluorescent speckle patterns were fabricated on wings, which emit red and blue spectra under ultraviolet light that were imaged and separated using a polarization RGB camera and auxiliary optical splitting components.
View Article and Find Full Text PDFSimultaneous monitoring of multiple fields of view (FOVs) by multiscale stereo-digital image correlation (stereo-DIC) can quantify the deformation of a material when localized phenomena occur within a larger FOV or moving object. In multiscale deformation measurement via stereo-DIC, optimization of the digital speckle patterns (DSPs) is essential to achieve high accuracy and efficiency. This work optimizes and fabricates multispectral DSPs used for multiple scales.
View Article and Find Full Text PDFThree species of the family Perlodidae are newly reported or confirmed for China, Isoperla asiatica Raušer from Arxan, Inner Mongolia Autonomous Region, Isoperla eximia Zapekina-Dulkeit from Changbai Mountain, Jilin Province, and Mesoperlina capnoptera (McLachlan, 1886) from Xinjiang Uygur Autonomous Region. Based on new material, additional taxonomic notes and images of another perlodid stonefly, Rauserodes epiproctalis (Zwick, 1997) is provided.
View Article and Find Full Text PDFWith the increase in digital image correlation (DIC) applications, the computational efficiency of DIC is becoming increasingly important. In previous studies, real-time DIC was realized with a relatively small subset. However, a small subset does not always include sufficient gray gradient information.
View Article and Find Full Text PDFThe new species, Hilethera xinjiangensis sp. nov. (Orthoptera: Acrididae: Oedipodinae) is described based on specimens collected from Xinjiang, northern China.
View Article and Find Full Text PDFIntroduction: This study evaluated free water loss-induced residual strain with and without axial compressive loading and assessed the mechanical effect of cyclic loading in fully hydrated and partially dehydrated root dentin.
Methods: Root dentin sections prepared from freshly extracted human premolars were used. Customized 3-dimensional digital image correlation was used to qualitatively and quantitatively analyze the residual strain induced by 2 hours of free water loss in different regions of root dentin.
Digital image correlation (DIC) is a well-known technique for non-contact, non-destructive, full-field deformation measurement in experimental solid mechanics. Although DIC has been widely used in science and engineering, the resolution of strain measurement with DIC is limited by imaging resolution and is much lower than that obtained with a strain gauge. To achieve a breakthrough in strain measurement using DIC, a camera array-based DIC method is proposed herein for high-resolution strain measurement.
View Article and Find Full Text PDFHigh-resolution deformation measurements in a functionally graded hard tissue such as human dentin are essential to understand the unbound water-loss mediated changes and their role in its mechanical integrity. Yet a whole-field, 3-dimensional (3D) measurement and characterization of fully hydrated dentin in both macro- and micro-scales remain to be a challenge. This study was conducted in 2 stages.
View Article and Find Full Text PDFThe technique of digital image correlation (DIC), which has been widely used for noncontact deformation measurements in both the scientific and engineering fields, is greatly affected by the quality of speckle patterns in terms of its performance. This study was concerned with the optimization of the digital speckle pattern (DSP) for DIC in consideration of both the accuracy and efficiency. The root-mean-square error of the inverse compositional Gauss-Newton algorithm and the average number of iterations were used as quality metrics.
View Article and Find Full Text PDFNoninvasive, three-dimensional (3-D), full-field surface deformation measurements of the human body are important for biomedical investigations. We proposed a 3-D noninvasive, full-field body sensor based on stereo digital image correlation (stereo-DIC) for surface deformation monitoring of the human body in vivo. First, by applying an improved water-transfer printing (WTP) technique to transfer optimized speckle patterns onto the skin, the body sensor was conveniently and harmlessly fabricated directly onto the human body.
View Article and Find Full Text PDFThe accuracy of strain measurement using a common optical extensometer with two-dimensional (2D) digital image correlation (DIC) is not sufficient for experimental applications due to the effect of out-of-plane motion. Although three-dimensional (3D) DIC can measure all three components of displacement without introducing in-plane displacement errors, 3D-DIC requires the stringent synchronization between two digital cameras and requires complicated system calibration of binocular stereovision, which makes the measurement rather inconvenient. To solve the problems described above, this paper proposes a self-calibration single-lens 3D video extensometer for non-contact, non-destructive and high-accuracy strain measurement.
View Article and Find Full Text PDFThe Holarctic diving beetle genus Graphoderus (Dytiscinae, Aciliini) contains relatively few and well-known species but these may still be difficult to identify based on external characters. A taxonomic problem in the eastern Palearctic was discovered that relates to the Palearctic Graphoderus zonatus (Hoppe, 1795) and the Nearctic Graphoderus perplexus Sharp, 1882. Based on qualitative and quantitative characters, especially on male genitalia which have been poorly studied in the past, it is shown that eastern Palearctic specimens identified by previous authors as either of the two species in fact belongs to a third species.
View Article and Find Full Text PDFIn industrial measurements and online monitoring, full-field and high-efficiency deformation analysis has been increasingly important and highly demanded in recent years. In this paper, a fast three-dimensional digital image correlation (3D-DIC) method was proposed to implement real-time measurement. Two improvements were suggested to accelerate the computation speed without sacrificing the accuracy.
View Article and Find Full Text PDFA lectotype is designated for the Tibetan species Deronectesemmerichi Falkenström, 1936 (Currently Boreonectesemmerichi (Falkenström)), and its habitus, as well as the median lobe and parameres of its aedeagus, are figured along with additional comparative material. Material of Boreonectesemmerichi from Sikkim (BMNH) represents the first record of a Boreonectes Angus, 2010 species from India. The karyotype of Boreonectesemmerichi is described as having 26 pairs of autosomes plus sex chromosomes which are X0 (♂), XX (♀).
View Article and Find Full Text PDFThe enzyme-inhibitor model and the sugar tolerance mouse model were used to evaluate the relationship between the inhibition rate of enzyme activity and concentration of Hippophae rhamnoides L. subsp. chinensis Rousi polysaccharide (HRP).
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