Three-dimensional surface morphometry differentiates behaviour on primate percussive stone tools.

In this study, we propose a three-dimensional (3D) surface temperature measurement method based on the principle of stereoscopic 3D reconstruction and the dependence of phosphorescence lifetime on temperature. A 385-nm UV(Ultraviolet) light was used as the excitation light, and two high-speed cameras were used as the detectors. The phosphor MFG (Mg4FGeO6: Mn4+) was mixed with the binder HPC and sprayed onto the tested 3D surface. The natural texture generated by the surface roughness of the phosphor coating was used as a feature for cross-correlation calculations. The digital image correlation (DIC) algorithm was used to match these feature positions in the phosphorescent images from the two cameras. The effects of the excitation angle and detecting angle were analyzed. The results indicate that the temperature measurement based on phosphorescent lifetime was not affected by the excitation and detecting angle. The method was validated on a turbine blade as an example of a 3D surface to demonstrate the capability. A comparison of the measurement results with the thermocouples proves that the current method can successfully measure the temperature on 3D surfaces with a maximum difference of 1.63°C. The spatial accuracy of the method was obtained by comparing with the measurement results of a 3D scanner, which shows that the maximum absolute error of the 3D reconstruction was 0.350 mm. The current study proposes a promising 3D surface temperature measurement method, which is expected to be widely used in gas turbine blades, Internal Combustion (IC) engine cylinders, complex curved heat exchangers, and other fields due to its non-contact measurement, low susceptibility to infrared radiation interference, high measurement accuracy, and ability to withstand harsh environments.

Aiming at the difficulty of deploying wireless sensor networks (WSNs) on three-dimensional (3D) surfaces, based on the grey wolf optimizer (GWO), an enhanced version of the grey wolf optimizer is proposed for deploying WSNs on 3D surfaces, namely the enhanced grey wolf optimizer (EGWO), which is characterized by enhanced exploitation and exploration ability of the algorithm. The novelty of EGWO is that the grey wolf population is divided into two parts, one part is responsible for the outer-layer encircle and the other is responsible for the inner-layer encircle, and the introduction of Tent mapping. The purpose of this is to enhance the exploitation and exploration ability of the algorithm respectively, so as to improve the convergence and optimization precision of the algorithm. In addition, in terms of WSN deployment in 3D surfaces, this paper improves the means of determining the perceived blind zone. Meanwhile, a novel method to calculate the WSNs coverage area of simple and complex 3D surfaces is presented by combining the grid and integral of the 3D surfaces. The EGWO is favorably compared with the GWO and three existing variants of the grey wolf optimizer when testing on 12 well-known benchmark functions. The simulation experiment results show that compared with the existing algorithms, EGWO can provide a very competitive search result in terms of optimization precision and convergence performance. Finally, this paper applies EGWO to the 3D surface deployment of WSN. Simulations show that compared with the other three deployment algorithms, EGWO can improve the network coverage of WSN, which can save network deployment costs. In addition, the probability of network connectivity deployed by EGWO is higher, that is, EGWO can provide a better deployment solution.

Utility of 3D Surface Laser Scanning in Brachytherapy of Lip Cancer

Commentary: Challenges of 3D Surface Image-based Prediction Models for Pectus Excavatum

Background: This study aimed to comprehensively evaluate the morphometric characteristics of the atlas (C1) and axis (C2) cervical vertebrae in Aksaray Malakli dogs. Using advanced three-dimensional (3D) surface scanning technology, the research provides detailed and breed-specific anatomical data for this unique dog breed. Methods: Seven atlas and seven axis bones were collected from adult Aksaray Malakli dogs and scanned using a color 3D surface scanner. High-resolution digital models of each bone were generated and a total of 25 linear and one angular osteometric measurements were performed on each model using specialized 3D analysis software. To ensure measurement reliability, all parameters were measured three times by the same researcher and intra-observer agreement was high for both vertebrae [intraclass correlation coefficient (ICC) greater than 0.75]. Result: Descriptive statistics and correlation analyses identified significant structural relationships among several morphometric parameters. Comparative assessments demonstrated that certain morphometric features of Malaklı dogs differ considerably from those of other dog breeds and mammalian species. Notably, the dens-to-axis length ratio (DALR) and dens angle (DAo) values provided critical insights into the predisposition of large breed dogs to atlantoaxial instability. Furthermore, the study confirmed the high reliability and repeatability of measurements obtained via 3D surface scanning. These findings establish essential baseline data for future anatomical investigations and offer novel comparative information on the morphometry of the Aksaray Malakli breed.

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Digital anthropometry is a useful tool for surgeons and patients in breast reconstruction surgery (BRS). Owing to advancements in smartphone technology, these devices can be used for three-dimensional (3D) surface imaging. In this prospective study, anthropometric measurements of the breast were performed using a smartphone and compared with measurements obtained using an established 3D surface imaging system. In this study, 40 patients who underwent BRS were included. 3D-surface models (SMs) were obtained using the Vectra H2 stereophotogrammetry camera (Canfield Scientific, USA) and an iPhone 15 (Apple Inc., USA) in combination with the 3D Scanner App (Laan Consulting Corp., USA). Fourteen measurements were performed on all 3D SMs. Subsequently, smartphone-based measurements were compared to Vectra-based measurements. Statistical methods used were the paired t-test, paired Wilcoxon-signed ranks test, Bland-Altman analyses, and calculation of the intraclass correlation coefficient (ICC). All measurements demonstrated excellent agreement between those obtained using the smartphone and Vectra H2 (ICC between.963 and.998). No statistical differences were found for 11 of the 14 anthropometric measurements. The Bland-Altman analyses yielded promising results, demonstrating 95% limits of agreement within a range of less than ±2mm between the 2 methods. The proposed method for smartphone-based anthropometry of the breast showed moderate accuracy for clinical use. However, the approach used to create and evaluate the 3D SMs is considered laborious. Therefore, further refinement of the method may be necessary to enable the implementation of smartphone-based surface imaging in plastic surgery. DRKS00034221.

Accurate small animal surface reconstruction is important for full angle non-contact fluorescence molecular tomography (FMT) systems. In this letter, an optimal surface reconstruction method for FMT is proposed. The proposed method uses a line search method to minimize the mismatch between the reconstructed three-dimensional (3D) surface and the projected object silhouette at different angles. The results show that the mean mismatches of the 3D surfaces generated on three live anesthetized mice are all less than two charge coupled device (CCD) pixels (0.154 mm). With the accurately reconstructed 3D surface, in-vivo FMT is also performed.

Manipulation of permanent magnet beads with head-to-tail ring formation on thin 3D surfaces

Accurate and rapid alignment of laser scanned 3D surface using TSK-type neural-fuzzy network-based coarse-to-fine strategy

The various methods of optimization or random search have been developed for locating the critical slip surface of a slope and the related minimum safety factor in the limit equilibrium stability analysis of slope. However, all these methods are based on a two-dimensional (2D) method and not one had been adapted for a search of the three-dimensional (3D) critical slip surface. In this paper, a new Monte Carlo random simulation method has been proposed to identify the 3D critical slip surface, in which assuming the initial slip to be the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is located by minimizing the 3D safety factor of limit equilibrium approach. Based on the column-based 3D limit equilibrium slope stability analysis models, new geographic information systems (GIS) grid-based 3D deterministic limit equilibrium models are developed to calculate the 3D safety factors. Several practical examples, of obtained minimum safety factor and its critical slip surface by a 2D optimization or random technique, are extended to 3D slope problems to locate the 3D critical slip surface and to compare with the 2D results. The results shows that, comparing with the 2D results, the resulted 3D critical slip surface has no apparent difference only from a cross-section, but the associated 3D safety factor is definitely higher.

ABSTRACTIdentifying the conditions that facilitate tool use is a central focus in the field of human evolution and animal behavior. Particular interest lies in studying stone tool use by non-human primates, especially when stone hammers are used to open encased food sources. Percussive tool use is a rare and complex technological behavior which was also employed by our early hominin ancestors. It is widely theorized that environmental factors play a role in explaining the presence and absence of stone tool use across primate populations. Research to date has focused heavily on the quality and availability of tool-extractable foods, and how these compare to alternative food sources. There has been limited investigation into whether access to different types of raw tool material for hammerstones and anvils affects the efficiency of tool users when exploiting encased resources. Here, we quantitatively analyzed how percussive tools of different raw materials vary in their performance and durability. Wild capuchins (Sapajus libidinosus) in Brazil were provided with stones sourced globally from primate and hominin tool use sites. We measured the reliability with which monkeys could crack nuts when using different raw materials, the number of strikes required to open a nut or obtain a food reward, and how these metrics changed over time. We further reported variations in the durability of different raw materials which directly relates to how long a tool remains usable. Our results showed that differences in nut cracking reliability and efficiency were largely driven by the ability of the tool material to stabilize the nut. Furthermore, there was wide variation in tool durability, particularly for anvils. These results highlight the importance of considering raw materials among the ecological factors that can influence the selective benefits or costs of tool use behaviors.HIGHLIGHTSRaw material influences primate percussive stone tool durability and performanceMaterials differ in their ability to stabilize food sourcesEfficiency of hammer strikes differed across materialsDifferences in material performance did not depend on their capacity to from pitsMaterial performance has consequences for food yield and energetic efficiency

Three-dimensional surface characterization for orthopaedic joint prostheses.

The Various methods of optimization or random search have been developed for locating the critical slip surface of a slope and the related minimum safety factor in the limit equilibrium stability analysis of slope. But all these methods are based on a two-dimensional (2D) method and no one had been adapted for a search of the three-dimensional (3D) critical slip surface. In this paper, a new Monte Carlo random simulating method has been proposed to identify the 3D critical slip surface, in which assuming the initial slip to be the lower part of an ellipsoid, the 3D critical slip surface in the 3D slope stability analysis is located by minimizing the 3D safety factor of limit equilibrium approach. Based on the column-based three-dimensional limit equilibrium slope stability analysis models, new Geographic Information Systems (GIS) grid-based 3D deterministic limit equilibrium models are developed to calculate the 3D safety factors. Several practical examples, of obtained minimum safety factor and its critical slip surface by a 2D optimization or random technique, are extended to 3D slope problems to locate the 3D critical slip surface and to compare with the 2D results. The results shows that, comparing with the 2D results, the resulting 3D critical slip surface has no apparent difference only from a cross section, but the associated 3D safety factor is definitely higher.

A GIS-based method for locating the critical 3D slip surface in a slope