The significance of shooting angle in seal shooting.

The present study aimed to investigate the relationship between shooting angle to the head and animal welfare outcomes in the hunt of young harp seals (Pagophilus groenlandicus). The study population consisted of young harp seals belonging to the Greenland Sea harp seal population. A sample of 171, 2-7 weeks old, weaned harp seals of both sexes were included. The study was conducted as an open, randomised parallel group designed trial during the regular hunt. The animals were allocated into four groups, A-D, according to the observed shooting angle to the head, defined as the angle between the direction of the shot and the longitudinal axis of the animal's head: (A) directly from the front; (B) obliquely from the front; (C) directly from the side; and (D) obliquely or directly from behind. Instantaneous death rate (IDR) and time to death (TTD) were the main variables. The mean IDR differed significantly between groups and was highest in group B (96.8%) and lowest in group C (66.7%). For all groups combined it was 84.2%. The mean TTD for seals not rendered instantaneously unconscious or dead (n = 27) differed significantly between groups and was shortest in group A (16 s) and longest in group C (85 s). However, the number of animals included in the TTD analysis was limited. In conclusion, based on the significantly higher IDR, the shooting angle obliquely from the front is recommended to help achieve the best animal welfare outcomes during the hunt of young harp seals.

Effect of Video Camera Angle on the Detection of Compensatory Movements during Motion Observation.

When exercise instructions are provided over the Internet, such as in online personal training, an instructor checks the user's form by watching their motion video recorded using a single camera device. However, fixed shooting angles may affect the detection of incorrect forms, including compensatory movements. This study aimed to verify whether differences in the shooting direction could influence compensatory movement detection by conducting motion observation using training motion videos shot from two angles. Videos of four training movements, including compensatory movements, were simultaneously captured from the front and side. Ten university students studying physical therapy watched the videos from each angle to detect compensatory movements. This study revealed significant differences between the plane of motion in which the compensatory action occurred and the direction of shooting for the false responses in the compensatory action detection for the three movements (p < 0.05). The results indicated that the shooting direction and the plane of motion in which the compensatory action occurred affected the detection of compensatory movements, which was attributable to differences in information on the amount of joint change depending on the direction of joint motion observation and to a lack of binocular visual information necessary for depth motion detection.

Biomechanical Adjustments of the Basketball Jump Shot Performed Over Differently High Opponents.

Biomechanical adjustments of the jump shot in presence of an opponent and their associations with shooting efficiency remain to be determined in elite basketball. The aim of this research was to examine the selected biomechanical determinants of the jump shot when shooting over opponents of different height. Nineteen elite basketball players, age 22 ± 3 years, performed three trials of 20 basketball shots in a crossover, randomised manner: over an obstacle of the height of standing reach (RH), over reach height with additional 20 cm (RH+20 cm), over reach height with additional 40 cm (RH+40 cm), and the maximum height jump shot without an obstacle (JSmax). Jump height, the ball entry angle, and shooting efficiency were measured on each trial. Jump height when shooting over RH+40 cm was significantly higher than RH+20 cm (+0.022 m, p = 0.030) and RH (+0.023 m, p = 0.029). Similarly, the ball entry angle was greater at RH+40 cm compared to RH (+7.19 °, p < 0.001) and RH+20 cm (+2.90°, p < 0.001). In contrast, shooting efficiency decreased significantly when shooting over RH+40 cm compared to RH (-10.79%, p = 0.048) and RH+20 cm (-8.95%, p = 0.015). We recorded the highest jump height (0.35 ± 0.08m, p < 0.001) and the lowest angle of entry (39.16 ± 1.19°, p < 0.001) when participants performed JSmax. Shooting over higher opponents should be prioritised in training to significantly improve shooting efficiency. Future research is needed to determine additional potential biomechanical determinants of a successful jump shot in elite basketball.

Distributed Small-Step Path Planning and Detection Method for Post-earthquake Robot to Inspect and Evaluate Building Damage.

Post-earthquake robots can be used extensively to inspect and evaluate building damage for safety assessment. However, the surrounding environment and path for such robots are complex and unstable with unexpected obstacles. Thus, path planning for such robot is crucial to guarantee satisfactory inspection and evaluation while approaching the ideal position. To achieve this goal, we proposed a distributed small-step path planning method using modified reinforcement learning (MRL). Limited distance and 12 directions were gridly refined for the robot to move around. The small moving step ensures the path planning to be optimal in a neighboring safe region. The MRL updates the direction and adjusts the path to avoid unknown disturbances. After finding the best inspection angle, the camera on the robot can capture the picture clearly, thereby improving the detection capability. Furthermore, the corner point detection method of buildings was improved using the Harris algorithm to enhance the detection accuracy. An experimental simulation platform was established to verify the designed robot, path planning method, and overall detection performance. Based on the proposed evaluation index, the post-earthquake building damage was inspected with high accuracy of up to 98%, i.e., 20% higher than traditional unplanned detection. The proposed robot can be used to explore unknown environments, especially in hazardous conditions unsuitable for humans.

Reconstruction method and optimum range of camera-shooting angle for 3D plant modeling using a multi-camera photography system.

BACKGROUND: Measurement of plant structure is useful in monitoring plant conditions and understanding the responses of plants to environmental changes. 3D imaging technologies, especially the passive-SfM (Structure from Motion) algorithm combined with a multi-camera photography (MCP) system has been studied to measure plant structure due to its low-cost, close-range, and rapid image capturing ability. However, reconstruction of 3D plant models with complex structure is a time-consuming process and some systems have failed to reconstruct 3D models properly. Therefore, an MCP based SfM system was developed and an appropriate reconstruction method and optimal range of camera-shooting angles were investigated. RESULTS: An MCP system which utilized 10 cameras and a rotary table for plant was developed. The 3D mesh model of a single leaf reconstruction using a set of images taken at each viewing zenith angle (VZA) from 12° (C2 camera) to 60° (C6 camera) by the MCP based SfM system had less undetected or unstable regions in comparison with other VZAs. The 3D mesh model of a whole plant, which merged 3D dense point cloud models built from a set of images taken at each appropriate VZA (Method 1), had high accuracy. The Method 1 error percentages for leaf area, leaf length, leaf width, stem height, and stem width are in the range of 2.6-4.4%, 0.2-2.2%, 1.0-4.9%, 1.9-2.8%, and 2.6-5.7% respectively. Also, the error of the leaf inclination angle was less than 5°. Conversely, the 3D mesh model of a whole plant built directly from a set of images taken at all appropriate VZAs (Method 2) had lower accuracy than that of Method 1. For Method 2, the error percentages of leaf area, leaf length, and leaf width are in the range of 3.1-13.3%, 0.4-3.3%, and 1.6-8.6%, respectively. It was difficult to obtain the error percentages of stem height and stem width because some information was missing in this model. In addition, the calculation time for Method 2 was 1.97 times longer computational time in comparison to Method 1. CONCLUSIONS: In this study, we determined the optimal shooting angles on the MCP based SfM system developed. We found that it is better in terms of computational time and accuracy to merge partial 3D models from images taken at each appropriate VZA, then construct complete 3D model (Method 1), rather than to construct 3D model by using images taken at all appropriate VZAs (Method 2). This is because utilization of incorporation of incomplete images to match feature points could result in reduced accuracy in 3D models and the increase in computational time for 3D model reconstruction.

Reproducibility of intraoral photography for pink and white tissue assessment - Is it worth the hassle?

PURPOSE: To assess the effect of the shooting angle variation on linear and planimetric measurements of the pink and white tissues on intraoral photographs. METHODS: From intraoral three-dimensional (3D) scans of the anterior region in 10 patients, ninety-nine two-dimensional (2D) "scan pictures" each were generated with different shooting angles, each varying in 5° horizontal and vertical increments. Eleven intraoral photographs of each patient and tooth site were taken free-hand: one shot at baseline and 5 shots after 3 and 6 months at slightly varying shooting angles. Papilla height (PH) and area (PA) and tooth crown area (TCA) were estimated on all photographs; the "best-match-to-baseline" photograph from those taken at 3 and 6 months was chosen by 6 evaluators. RESULTS: Within the first 10° of deviation from the baseline shooting angle, measurements on the 2D "scan pictures" distorted ≤0.5 mm for PH and ≤10% for PA and TCA. Compared to baseline, only 6 out of 100 photographs presented ≥0.5 mm difference in PH, none of the TCA measurements showed distortion ≥10%, and only in 4 instances a ≥10% distortion of the PA was observed. Poor to moderate inter- and intra-rater agreement in choosing the "best-match-to-baseline" photograph was found, but photographs with clinically relevant changes were only seldomly chosen. CONCLUSIONS: Deviations in the shooting angle ≤10° from the baseline shot cause clinically negligible distortions in linear and planimetric measurements. Highly comparable intraoral photographs of the anterior maxillary teeth can be captured "free-hand" in slightly varying perspective, and then selecting the "best-match-to-baseline".