- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[ACM Press the Ninth International Symposium - Danang City, Viet Nam (2018.12.06-2018.12.07)] Proceedings of the Ninth International Symposium on Information and Communication Technology - SoICT 2018 - Calf Robust Weight Estimation Using 3D Contiguous Cylindrical Model and Directional Orientation from Stereo Images
摘要： Calving interval is often used as an indicator for fertility of beef cattle, however, maternal abilities are also required because the value of breeding cows depends on how efficiently the healthy and growing calves are produced. The calf's weight has been used as an indicator of maternity ability since the past few decades. We propose a method to estimate body weight by modeling the shape of calf using 3D information extracted from the stereo images. This method enables to predict the swelling of the cattle's body by creating a 3D model, which cannot be obtained solely from a 2D image. In addition, it is possible to estimate robust weight regardless of different shooting conditions toward cattle's posture and orientation. An image suitable for estimation is selected from motion images taken by the camera installed in the barn, and 3D coordinates are calculated by the images. Then, only the body is developed with a 3D model as it has the highest correlation with the body weight. Considering that the side of cattle's body may not be exactly perpendicular to the camera's shooting direction, a symmetric axis is extracted to find the inclination of cattle body from the camera in order to generate a 3D model based on the symmetric axis. 3D contiguous cylindrical model is used for the body of a cattle which has a rounded shape. In order to manipulate the shapes of the cylindrical surface, the circle and ellipse fittings are applied and compared. The linear regression equation of the volume of the cylindrical model and the actually measured body weight are used to estimate the cattle weight. As a result of modeling with the proposed method using the actual camera images, the correlation coefficient between the body weight and the model volume was at the best value, 0.9107. Even when experimentally examined with the different 3D coordinates obtained from other types of camera, the MAPE (Mean Absolute Percentage Error) was as low as 6.39%.
关键词： depth camera,circle fitting,three-dimensional reconstruction,weight estimation,calf,cow,stereo camera,cattle,ellipse fitting
更新于2025-09-23 15:23:52
-
Visualization of biological macromolecules at near-atomic resolution: cryo-electron microscopy comes of age
摘要： Structural biology is going through a revolution as a result of transformational advances in the field of cryo-electron microscopy (cryo-EM) driven by the development of direct electron detectors and ultrastable electron microscopes. High-resolution cryo-EM images of isolated biomolecules (single particles) suspended in a thin layer of vitrified buffer are subjected to powerful image-processing algorithms, enabling near-atomic resolution structures to be determined in unprecedented numbers. Prior to these advances, electron crystallography of two-dimensional crystals and helical assemblies of proteins had established the feasibility of atomic resolution structure determination using cryo-EM. Atomic resolution single-particle analysis, without the need for crystals, now promises to resolve problems in structural biology that were intractable just a few years ago.
关键词： direct detectors,single-particle analysis,cryo-EM,three-dimensional reconstruction,phase plates
更新于2025-09-23 15:22:29
-
Three-dimensional view of out-of-plane artifacts in photoacoustic imaging using a laser-integrated linear-transducer-array probe
摘要： Research on photoacoustic imaging (PAI) using a handheld integrated photoacoustic probe has been a recent focus of clinical translation of this imaging technique. One of the remaining challenges is the occurrence of out-of-plane artifacts (OPAs) in such a probe. Previously, we proposed a method to identify and remove OPAs by axially displacing the transducer array. Here we show that besides the benefit of removing OPAs from the imaging plane, the proposed method can provide a three-dimensional (3D) view of the OPAs. In this work, we present a 3D reconstruction method using axial transducer array displacement. By axially displacing the transducer array, out-of-plane absorbers can be three-dimensionally visualized at an elevation distance of up to the acquired imaging depth. Additionally, OPAs in the in-plane image are significantly reduced. We experimentally demonstrate the method with phantom and in vivo experiments using an integrated PAI probe. We also compare the method with elevational transducer array displacement and take into account the sensitivity of the transducer array in the 3D reconstruction.
关键词： Out-of-plane artifact,Three-dimensional reconstruction,Linear array,Beamforming
更新于2025-09-23 15:21:01
-
[IEEE 2019 4th International Conference on Mechanical, Control and Computer Engineering (ICMCCE) - Hohhot, China (2019.10.24-2019.10.26)] 2019 4th International Conference on Mechanical, Control and Computer Engineering (ICMCCE) - Design of a Stroboscopic Laser Grating Stripe Projection Device
摘要： A three-dimensional measuring system based on a line-structured laser and a high-speed rotating multi-faced prism has been designed and described in detail. The grating fringe can be produced using stroboscopic effect the system. The relationship between grating stripe and modulation signal and prism rotation speed are analyzed from both theoretical and experimental aspects. At the same time, the grating stripe projection device is applied to the three-dimensional measurement of gypsum section.
关键词： grating fringe,stroboscopic effect,laser,three-dimensional reconstruction
更新于2025-09-23 15:19:57
-
Reconstruction of 3D structure for nanoscale biological objects from experiments data on super-bright X-ray free electron lasers (XFELs): dependence of the 3D resolution on the experiment parameters
摘要： The ability to investigate 3D structure of biomolecules, such as proteins and viruses, is essential in biology and medicine. With the invention of super-bright X-ray free electron lasers (e.g. European XFEL and Linac Coherent Light Source (LCLS)) the Single Particle Imaging (SPI) approach allows to reconstruct 3D structures from many 2D diffraction images produced in the experiment by X-rays scattered on the biomolecule exposed in different orientations. In the same time, there are still many challenging problems in experiment setup, sample preparation and injection, which limit number and quality of obtained diffraction patterns and, consequently, limit achievable resolution of recovered 3D structure. However even with the current experimental limitations it is possible to reconstruct 3D structures of some large biomolecules. An important question arises: what range of 3D resolution is possible to achieve under experimental conditions available now. We investigated how the number and quality of diffraction images affect the 3D resolution. First the SPI experiment was simulated and reconstructed with the Dragonfly software. Then we analyzed how the number of diffraction images and the beam intensity affect the final 3D resolution. We come to the following conclusions: 1) starting from the beam intensity value (fluence) equal to 3×1012 photons/μm2 the resolution becomes to be almost constant; 2) the resolution strongly depends on the number of diffraction patterns. More than 10 000 diffraction images are required to get 4 nm resolution.
关键词： Single Particle Imaging,Three-dimensional Reconstruction,X-ray Free Electron Laser,space resolution
更新于2025-09-19 17:13:59
-
Comparison of diagnostic performance in assessing the rewiring position into a jailed side branch between online 3D reconstruction systems version 1.1 and 1.2 derived from optical frequency domain imaging
摘要： The three-dimensional reconstruction of optical coherence tomography and optical frequency domain imaging (3D-OCT/OFDI) helps optimize bifurcation percutaneous coronary interventions (PCIs) with side branch (SB) dilatation by identifying the optimal rewiring position. 3D-OCT/OFDI’s diagnostic performance for assessing the rewiring position into a jailed SB is unknown. We retrospectively evaluated the diagnostic performances of a conventional (ver. 1.1) and a new (ver. 1.2) online 3D-OFDI reconstruction system based on an offline 3D reconstruction system’s performance. We analyzed 45 patients’ 52 OFDI pullbacks with main vessel stenting followed by rewiring into a jailed SB for coronary bifurcation lesions. We counted the undetected stent struts in the polygon of confluence as the stent detection performance. We assessed the diagnostic agreement regarding the rewiring position into a jailed SB by the three 3D reconstruction systems. The percentage of undetected struts and the diagnostic agreement of ver.1.2 were significantly better than those of ver.1.1 [5.1 ± 5.1% vs. 30.2 ± 14.2%; p < 0.0001, and 94.2% (49/52) vs. 76.9% (40/52); p = 0.0120]. The new online 3D-OFDI reconstruction system provides better diagnostic performance than the conventional online system for assessing the rewiring position into a jailed SB.
关键词： Three-dimensional reconstruction,Agreement comparison,Coronary bifurcation stenting,Optical frequency domain imaging,Kissing balloon inflation
更新于2025-09-12 10:27:22
-
Online weld pool contour extraction and seam width prediction based on mixing spectral vision
摘要： In this paper, based on gas–metal–arc welding (GMAW), we used a passive vision sensing system and proposed a double-path imaging method to capture weld pool images, and empirically and theoretically demonstrated the optimal bands. According to the mixed spectra of self-emitted radiation of the weld pool and the arc spectra, we selected 660-nm narrowband and 850-nm long-pass as the system’s working bands. Two cameras with 660-nm narrowband filter and 850-nm long-pass filter were used to capture weld pool images at the background level through a synchronous acquisition equation and weld pool images with high signal-to-noise ratio were obtained. After image registration, we used Gradient and Gray-based Neighbor Superpixel Merging (GNSM) method to extract the contour of weld pool image. Comparing with other algorithms, the proposed algorithm can obtain an effective and accurate contour of the weld pool image. Then we proposed an online seam width prediction method before seam formation which is based on the contour of the weld pool image. We used Gaussian distribution to fit the pixel width of the contour and the corresponding seam width measured by three-dimensional reconstruction. By comparatively analyzing the fitting deviation and the actual measurement results, we concluded that the deviation of weld seam width prediction was within 0.20 mm.
关键词： Three-dimensional reconstruction,Superpixel segmentation,Seam width prediction,Vision sensing system,Double-band imaging,Contour of weld pool
更新于2025-09-04 15:30:14