3d photogrammetry
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2021 ◽  
pp. 105566562110628
Author(s):  
Miles J. Pfaff ◽  
Madeleine K. Bruce ◽  
Sarah Erpenbeck ◽  
Aditya Mittal ◽  
Justin W. Beiriger ◽  
...  

Introduction The concept of “overcorrection” for trigonocephaly has been reported to achieve both anterior cranial fossa expansion and normalization of craniofacial form. The purpose of this study is to describe in detail a standardized technique to fronto-orbital advancement utilizing the concept of “overcorrection” and objectively evaluate intermediate results. Methods This retrospective study included patients with isolated metopic synostosis who underwent surgery via the proposed surgical technique and age and sex-matched unaffected controls. Craniofacial morphometric analysis was performed on pre-, immediate post-, and intermediate postoperative (>2 years) three-dimensional (3D)-rendered computed tomographic (CT) scans and photographs. Key CT-based measurements included interzygomaticofrontal suture distance (IZFS), endocranial bifrontal angle (ECA), and temporal expansion. 3D photogrammetry was performed using established measurements and associated Z-scores converted. A Paired t-test and analysis of variance were performed when appropriate. Results Forty-one patients were included. A comparison of pre- and immediate postoperative CT scans demonstrated statistically significant increases in all measurements. Subset analysis of 12 patients with intermediate follow-up (age: 39.6 ± 3.6 months) demonstrated significant differences from preoperative values except for IZFS, which decreased from immediate postoperative values and was smaller than age- and sex-matched controls. 3D photogrammetry demonstrated a mean Z-score above the norm for frontal breath. 3D photogrammetry is also positively correlated with CT-based measurements. Conclusions This standardized “overcorrection” approach for trigonocephaly can provide the appropriate changes to maintain a normal ECA despite a reduction in bifrontal width over time. 3D photogrammetry positively correlated with CT-based measurements and may provide useful information when following patients clinically. Long-term follow-up assessment to determine the necessary degree of overcorrection at skeletal mature is needed.


Nature ◽  
2021 ◽  
Author(s):  
Ellison J. McNutt ◽  
Kevin G. Hatala ◽  
Catherine Miller ◽  
James Adams ◽  
Jesse Casana ◽  
...  

AbstractBipedal trackways discovered in 1978 at Laetoli site G, Tanzania and dated to 3.66 million years ago are widely accepted as the oldest unequivocal evidence of obligate bipedalism in the human lineage1–3. Another trackway discovered two years earlier at nearby site A was partially excavated and attributed to a hominin, but curious affinities with bears (ursids) marginalized its importance to the paleoanthropological community, and the location of these footprints fell into obscurity3–5. In 2019, we located, excavated and cleaned the site A trackway, producing a digital archive using 3D photogrammetry and laser scanning. Here we compare the footprints at this site with those of American black bears, chimpanzees and humans, and we show that they resemble those of hominins more than ursids. In fact, the narrow step width corroborates the original interpretation of a small, cross-stepping bipedal hominin. However, the inferred foot proportions, gait parameters and 3D morphologies of footprints at site A are readily distinguished from those at site G, indicating that a minimum of two hominin taxa with different feet and gaits coexisted at Laetoli.


2021 ◽  
Vol 2021 ◽  
pp. 9-17
Author(s):  
A. Rudolf ◽  
Z. Stjepanović ◽  
A. Cupar

In recent years, the 3D design software has been mostly used to improve the garment design process by generating virtual 3D garment prototypes. Many researchers have been working on the development of 3D virtual garment prototypes using 3D body models and involving the 3D human body scanning in different postures. The focus of research in this field today relies on generating a kinematic 3D body model for the purposes of developing the individualized garments, the exploration of which is presented in this paper. The discussed area is also implemented in the Erasmus+ project OptimTex - Software tools for textile creatives, which is fully aligned with the new trends propelled by the digitization of the whole textile sector. The Slovenian module focuses on presenting the needs of digitization for the development of individualized garments by using different software tools: 3D Sense, PotPlayer, Meshroom, MeshLab, Blender and OptiTex. The module provides four examples: 3D human body scanning using 3D photogrammetry, 3D human body modelling and reconstruction, construction of a kinematic 3D body model and 3D virtual prototyping of individualized smart garments, and thus displays the entire process for the needs of 3D virtual prototyping of individualized garments. In the OptimTex project, the 3D software Blender was used to demonstrate and teach students how to construct the "armature" of the human body as an object for rigging or the virtual skeleton for a 3D kinematic body model, using the knee as an example.


2021 ◽  
Vol 873 (1) ◽  
pp. 012052
Author(s):  
Mudrik Rahmawan Daryono ◽  
Danny Hilman Natawidjaja ◽  
Anggraini Rizkita Puji ◽  
Sonny Aribowo

Abstract Baribis Fault is a recently identified active fault known to have thrust movement which located along the northern part of the West Java area. This E-W striking fault runs across high-populated areas, including Cirebon, Indramayu, Sumedang, and Subang area (with a probability of continuing to Jakarta and Banten areas). The last major historical earthquake occurred on November 16th, 1847 around the fault line with a radius of shaking area up to 400 km. The available high-resolution Digital Elevation Model from Geospatial Information Agency, called DEMNAS, has about 7.5-m grid data resolution but still not adequate to be used for identifying fault ruptures of this event. Hence, we conducted an Unmanned Aerial Vehicle (UAV) 3D Photogrammetry survey flown in the lower latitude (~100-m high) in the suspected sites. This study identified clear fault scarp associated with stream-valley offsets indicating strike-slip movement in the Ujung Jaya subdistrict, Sumedang. The trace of fault rupture has a 5±1-meter sinistral offset. This sharp fault deformation feature is possibly related to the 1847 earthquake in this area. This fact is different from regional morphology, which shows that the Baribis Fault is a thrust. Further study is necessary to get more detailed and precise information.


2021 ◽  
Vol 8 ◽  
Author(s):  
Daniel D. Conley ◽  
Erin N. R. Hollander

The wax dip method typically used to determine the surface area of corals for data normalization is destructive, rendering the collection of time series for such data impossible. With recent advancements in photogrammetric technology, it is now possible to collect these data in a non-destructive manner at very high levels of accuracy. This photogrammetric method using Agisoft’s Metashape is compared to the standard wax-dip method using both objects of known surface area and objects of unknown surface area. Objects of known surface area (i.e., objects that have surface areas that can be calculated using geometrical formulas) were estimated with a similar degree of accuracy with the Photogrammetry (PG) method (R2 = 0.9922, slope = 0.9835) as with the wax-dip method (R2 = 0.9872, slope = 1). A single factor ANOVA confirmed that there was no significant difference between measurements from the three methods of geometrical calculation, wax dipping, or photogrammetry for objects of known surface area. This paper describes the methods for rapidly collecting surface area data of small to moderately sized coral nubbins in a laboratory setting and characterizes the relationship between buoyant weight and surface area over time for the coral species Stylophora pistillata. Finally, two predictive models are proposed to estimate surface area from weight in air measurements.


Author(s):  
Andres Mármol-Guijarro ◽  
Robert Nudds ◽  
Lars Folkow ◽  
William Sellers ◽  
Peter Falkingham ◽  
...  

Abstract Substrate supportiveness is linked to the metabolic cost of locomotion, as it influences the depth to which the foot of a moving animal will sink. As track depth increases animals typically reduce their speed to minimise any potential energetic imbalance. Here we examine how self-selected speed in the Svalbard rock ptarmigan is affected by snow supportiveness and subsequent footprint depth measured using thin-blade penetrometry and 3D photogrammetry, respectively. Our findings indicate that snow supportiveness and footprint depth are poor predictors of speed (r2 = 0.149) and stride length (r2 = 0.106). The ptarmigan in our study rarely sunk to depths beyond the intertarsal joint, regardless of the speed, suggesting that at this relatively shallow depth any increased cost is manageable. 3D reconstructions also indicate that the ptarmigan may exploit the compressive nature of snow to generate thrust during stance, as a trend towards greater foot rotations in deeper footprints was found. It remains unclear if the Svalbard ptarmigan are deliberately avoiding unsupportive snowy substrates. However, if they do, these results would be consistent with the idea that animals should choose routes that minimise energy costs of locomotion. Resumen La firmeza del sustrato se asocial al costo metabólico de la locomoción ya que influencia cuán profundo las extremidades de un animal se hunden al moverse. A medida hundimiento aumenta, usualmente los animales reducen su velocidad para minimizar potenciales desbalances energéticos. En este estudio examinamos cómo la velocidad de la perdiz de la roca de Svalbard es afectada por la firmeza del sustrato y la profundidad de hundimiento de sus patas, usando penetrometría y fotogrametría 3D, respectivamente. Nuestros resultados indican que la firmeza de la nieve y la profundidad de hundimiento de las patas no son buenos predictores de la velocidad (r2 = 0.149) y de la longitud de la zancada (r2 = 0.106). La profundidad de las huellas de las perdices de nuestro estudio rara vez sobrepasó la altura de la articulación intertarsal, independientemente de la velocidad de locomoción, sugiriendo que a profundidades relativamente menores los costos energéticos son manejables. Las reconstrucciones 3D también indican que las perdices podrían aprovechar la naturaleza compresiva de la nieve para generar suficiente empuje durante la fase de soporte, ya que se encontró una tendencia hacia mayores rotaciones de la pata en huellas más profundas. Es incierto si las perdices de Svalbard deliberadamente evitan áreas con nieve más blanda. Sin embargo, si lo hacen, estos resultados serían consistentes con la idea de que los animales deberían seleccionar rutas que minimizan los gastos energéticos en locomoción.


FACE ◽  
2021 ◽  
pp. 273250162110290
Author(s):  
Adegbayi Adeola Adekunle ◽  
Abiodun Yusuff Olowo ◽  
Moses Adetona ◽  
Olutayo James ◽  
Olawale Olatubosun Adamson ◽  
...  

Objectives: The aim of the study is to highlight variations in facial anthropometric measurements among the major ethnic groups in Nigeria using 3D photogrammetry. Materials and Methods: This study was conducted in Lagos, Nigeria. Acquisition of 3D facial photographs was done using a Vectra H1 portable 3D photogrammetry imaging system. Descriptive analysis of collected data was done and a test of associations performed using independent samples t-test. The level of significance was set at <.05. Results: The total number of participants in this study was 503. The study population was made up of 302 (60%) males and 201 (40%) females. Mean upper facial height among Yoruba, Igbo, Hausa, and other ethnic groups were 68.93 ± 5.85, 70.18 ± 5.99, 63.79 ± 4.80, and 69.29 ± 5.95 mm respectively, while mean interpupillary distances were 66.99 ± 3.70, 67.34 ± 3.56, 66.73 ± 3.80, and 67.09 ± 3.72 mm respectively. A Tukey posthoc test revealed significant pairwise differences for upper facial height between the Yoruba and Hausa population with a mean difference of 5.15 mm ( P < .001, 95% CI 2.94-7.35) ( P < .001, 95% CI 2.94-7.35), and Hausa and Igbo population with a mean difference of 6.39 mm ( P < .001, 95% CI 3.75-9.03). Multivariate regression analysis confirmed the presence of significant inter-ethnic differences between Hausa ethnic group and the Yoruba ethnic group for midfacial height ( P < .001), upper lip height ( P = .004), lower lip height ( P = .003), total face height ( P = .010), and orbital fissure width ( P < .001). Conclusion: The result of this study shows that distinct difference does exist in the facial anthropological measurements between the ethnicities included in this study especially in vertical facial measurements.


PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252593
Author(s):  
Ian R. Combs ◽  
Michael S. Studivan ◽  
Ryan J. Eckert ◽  
Joshua D. Voss

Since 2014, stony coral tissue loss disease (SCTLD) has contributed to substantial declines of reef-building corals in Florida. The emergence of this disease, which impacts over 20 scleractinian coral species, has generated a need for widespread reef monitoring and the implementation of novel survey and disease mitigation strategies. This study paired SCTLD prevalence assessments with colony-level monitoring to help improve understanding of disease dynamics on both individual coral colonies and at reef-wide scales. Benthic surveys were conducted throughout the northern Florida Reef Tract to monitor the presence/absence of disease, disease prevalence, and coral species affected by SCTLD. Observed SCTLD prevalence was lower in Jupiter and Palm Beach than in Lauderdale-by-the-Sea or St. Lucie Reef, but there were no significant changes in prevalence over time. To assess colony-level impacts of the disease, we optimized a low-cost, rapid 3D photogrammetry technique to fate-track infected Montastraea cavernosa coral colonies over four time points spanning nearly four months. Total colony area and healthy tissue area on fate-tracked colonies decreased significantly over time. However disease lesion area did not decrease over time and was not correlated with total colony area. Taken together these results suggest that targeted intervention efforts on larger colonies may maximize preservation of coral cover. Traditional coral surveys combined with 3D photogrammetry can provide greater insights into the spatiotemporal dynamics and impacts of coral diseases on individual colonies and coral communities than surveys or visual estimates of disease progression alone.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Xiaoyong Luo ◽  
Hao Long ◽  
Shuang Dong ◽  
Jingyi Wu

The research objects of this paper were the prefabricated concrete components produced by four enterprises in China, and the dimension deviation data of more than 1400 prefabricated concrete components are measured with high-precision 3D photogrammetry technology. The nonparametric Kruskal–Wallis test was carried out for the size deviation of the same type of components produced by different enterprises. The distribution characteristics of geometric parameters of typical components of prefabricated structures in China, such as beams, columns, wall boards, and composite slabs, were analyzed by using the probability statistical method. The Kolmogorov–Smirnov goodness-of-fit method was used to test the cumulative distribution function of dimension deviation, and the size distribution of fabricated components was studied. The results showed that there was no significant difference in the size deviation of the same-type component produced by different enterprises, and the range of geometric parameter uncertainty random variables was small, which was between 0.99 and 1.02. Also, the fluctuation was small, the coefficient of variation was below 0.0093, and the variability of component size deviation was small. The transverse dimension of the component shows a positive deviation, the vertical dimension of component shows a negative deviation, and the dimension deviation of prefabricated concrete components follows the normal distribution.


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