Shape Of Pattern Research Articles

Enhancing mechanism of mechanical properties of lightweight and high-strength concrete prepared with autoclaved silicate lightweight aggregate

Lightweight aggregate concrete (LAC) possesses the merits of low density, excellent thermal insulation performance and outstanding seismic performance. However, the practical application in structural engineering is limited because its mechanical properties are weaker than those of ordinary aggregate concrete. It was found that the compressive strength of high-strength concrete prepared by autoclaved silicate lightweight aggregate (cloud concrete stone) was higher than that of ordinary aggregate high-strength concrete, and it showed significant lightweight and high-strength characteristics. To reveal the enhancing mechanism of the mechanical properties of high-strength concrete prepared by cloud concrete stone (CCS), this research examines the internal curing effect of CCS and the mechanical performances of the interfacial transition zones (ITZ). The influences of the elastic modulus of CCS, the shape of aggregate and fracture patterns on the mechanical properties of concrete are simulated via the discrete element method. The findings suggest that the internal curing effect of CCS delays the onset of capillary stress and mitigates autogenous shrinkage. The homogeneousness, elastic modulus, and fracture toughness of ITZ around CCS aggregate are superior than that ITZ around ordinary gravel in high-strength concrete. Furthermore, the small difference in elastic modulus between CCS aggregate and cement matrix is advantageous for preventing microcracks during compression tests. The round shape of the aggregate also mitigates the development of microcracks caused by the stress concentration effect. These three reasons contribute to the enhancement of mechanical properties in lightweight and high-strength concrete. The innovation of this research is that the intrinsic relationship between CCS aggregate and concrete’s mechanical properties is thoroughly revealed from the aspects of the characteristics of the interface transition zone, the morphology of the aggregate and the elastic modulus of aggregate. That provides a theoretical basis for the application of light aggregate in high-strength structural concrete.

Simulating irregular symmetry breaking in gut cross sections using a novel energy-optimization approach in growth-elasticity

Growth-elasticity (also known as morphoelasticity) is a powerful model framework for understanding complex shape development in soft biological tissues. At each instant, by mapping how continuum building blocks have grown geometrically and how they respond elastically to the push-and-pull from their neighbors, the shape of the growing structure is determined from a state of mechanical equilibrium. As mechanical loads continue to be added to the system through growth, many interesting shapes, such as smooth wavy wrinkles, sharp creases, and deep folds, can form on the tissue surface from a relatively flatter geometry.Previous numerical simulations of growth-elasticity have reproduced many interesting shapes resembling those observed in reality, such as the foldings on mammalian brains and guts. In the case of mammalian guts, it has been shown that wavy wrinkles, deep folds, and sharp creases on the interior organ surface can be simulated even under a simple assumption of isotropic uniform growth in the interior layer of the organ. Interestingly, the simulated patterns are all regular along the tube’s circumference, with either all smooth or all sharp indentations, whereas some undulation patterns in reality exhibit irregular patterns and a mixture of sharp creases and smooth indentations along the circumference. Can we simulate irregular indentation patterns without further complicating the growth patterning?In this paper, we have discovered abundant shape solutions with irregular indentation patterns by developing a Rayleigh–Ritz finite-element method (FEM). In contrast to previous Galerkin FEMs, which solve the weak formulation of the mechanical-equilibrium equations, the new method formulates an optimization problem for the discretized energy functional, whose critical points are equivalent to solutions obtained by solving the mechanical-equilibrium equations. This new method is more robust than previous methods. Specifically, it does not require the initial guess to be near a solution to achieve convergence, and it allows control over the direction of numerical iterates across the energy landscape. This approach enables the capture of more solutions that cannot be easily reached by previous methods. In addition to the previously found regular smooth and non-smooth configurations, we have identified a new transitional irregular smooth shape, new shapes with a mixture of smooth and non-smooth surface indentations, and a variety of irregular patterns with different numbers of creases. Our numerical results demonstrate that growth-elasticity modeling can match more shape patterns observed in reality than previously thought.

Factors influencing wildmeat trade in Guyana and expected changes in the context of the oil-related development prospects

The recent offshore oil discovery in the Guiana Shield is expected to bring about significant changes to the area, such as increased GDP per capita, infrastructure development, and urbanization. The potential impact on the wild meat trade depends on factors influencing its demand and provision. Through interviews and group discussions with trade chain stakeholders in all towns of Guyana, we evaluate wildmeat trade sector and explored predicted changes on it in 2033 with the prospects for short term oil-related development. The most traded species in Guyana included paca, white-lipped peccary, deer, tapir and capybara and a total of 38.46 % (5 out of 13) of the taxa being traded is classified as threatened of extinction. Regions with higher population size and GDP per capita, are the main trade hubs for wildmeat. Access to improved preservation methods (e.g. freezers) and motorized transportation options (eg.: boat with engines and vehicles) significantly influence higher volumes of wildmeat traded. The economic growth anticipated in Guyana is expected to boost population growth and, by the same time, wildmeat demand in urban areas. Concomitantly, with improved infrastructure and increased access to electricity, wildmeat provision will be facilitated across a wider catchment area. Based on the assumption that cultural patterns shaping wildmeat demand and environmental regulations will likely not change at the same rapid path as economic growth in the next ten years, we predict wildmeat trade volumes to increase to 10,280 tons/year by 2033. We identify three main opportunities to ensure a sustainable wildmeat sector in the context of the economic boom: First, the sector requires to be well regulated through a licensing and a quota system that can be adequately enforced. Second, efforts to curve demand on the Coast need to be strengthened based on well designed and culturally adapted behaviour change campaigns. Third, local communities and indigenous people need to be empowered to protect and conserve their territories and wildlife resources, in particular with the authority to exclude illegal hunters.

Radiation Pattern Analysis and Phase Shifter for Base Station Mobile Communication Circular Array Antenna at 900MHz Frequency by Using 4NEC2X Software

Background: This paper presents the utilization of phase shifters to manipulate and control the radiation patterns in Uniform Circular Array (UCA) antennas. UCAs, known for their 360-degree coverage and symmetrical radiation patterns, are enhanced by incorporating phase shifters, enabling dynamic beam steering and pattern shaping. Materials and Methods: A uniform circular antenna array operating at 900 GHz frequency has been intended for use in base stations using 4NEC2X simulation software. Results: A single-element dipole antenna having a 2.14 dBi gain is used as a base for constructing a uniform 0.5 λ spacing circular array. The number of elements gradually increased from 2 to 12, raising the gain to 12.3 dBi. HPBW decreased both in vertical and horizontal plans from 80o to 60o and 360o to 20o respectively this implies that the circular array antenna's directivity is enhanced. The eight-element array beam scanning was performed from 0o to 360o without any distortion in radiation pattern, gain, and directivity, contradictory with the linear array. Conclusions: The studied case and simulation output illustrate the impact of the element numbers and phase shifter configurations on properties of the radiation pattern of the uniform circular array can be obtained when increasing the number of elements, the gain increases too and scanning the main beam without any change and distortion

Design and fabrication of integrated negative feedback resistor for InGaAs/InP avalanche photodiode

The serial resistor of alloy material can be integrated on negative feedback avalanche diodes to reduce afterpulsing effect. In this work, the influence of parasitic capacitance on the avalanche quenching resistor was theoretically analyzed. By using simulation model of device & circuit mixed-mode, the quenching capability of integrated resistors was evaluated with the parasitic parameters. For the material growth of feedback quenching resistor, thin film based on CrSi alloy was prepared by ion beam sputtering process, realizing the sheet resistance of 3 kΩ/square. The resistor material were sufficiently investigated by characterizing the morphology and element component. CrSi pattern of spiral shape was fabricated on sapphire substrate, realizing a resistor of the order of 500 kΩ in area of diameter 40 μm, which was equivalent to the active area of avalanche diodes. The electrical measurement indicated the excellent temperature stability of this integrated resistor, showing the promising application prospect for preparing high-performance negative feedback avalanche diodes.

Influence of Silver Nanoparticle Integration on the Composition and Surface Properties of Acrylic Dental Resins Employed in Temporary Bridges

Background: Recognized widely for its irreversible effects, periodontal disease stands as one of the most prevalent conditions, particularly emphasizing the potential for permanent damage caused by gingivitis, extending to encompass the entirety of the supportive complex, including the connective tissue and alveolar bone. Patients necessitating comprehensive periodontal and prosthetic treatments require an interdisciplinary approach, involving the coordination of pre-treatment procedures and appropriate prosthetic strategies. The adoption of advanced materials and techniques can prove beneficial in addressing complex dental issues. (2) Methods: Forty specimens were prepared using the prescribed procedure, with 20 acting as controls and the other 20 integrating AgNPs. The initial step involved crafting wax patterns of distinct shapes: dumbbell shapes for tensile testing and rectangular shapes for roughness assessments. These dimensions were aligned with ASTM D-638 and ISO 527-2 standards and adjusted to match the specifications of the analysis device for mechanical properties. (3) Results: In this case, the results indicate minimal differences in heat-curing acrylic resins compared to the control samples at a 5% concentration. However, notable disparities arise at concentrations of 10% and 20%. (4) Conclusions: Temporary prosthetic constructions are essential for preventing functional imbalances and complications. Incorporating AgNPs at a 5% concentration maintains mechanical properties while providing antibacterial effects for long-term interim prosthodontic restorations. Higher nanoparticle concentrations may reduce resin mechanical properties without affecting material surface condition

RELIGIOUS TOLERANCE IN BANDA ACEH AND KEDIRI: CHALLENGES AND OPPORTUNITIES IN DIGITAL SPACE

This research explores religious tolerance in Banda Aceh and Kediri within the context of digital space, focusing on the genealogy, contestation, and development directions of religious tolerance. The aim is to understand the social and cultural dynamics shaping patterns of religious tolerance in these regions and how digital spaces influence interfaith interactions. The methodology employed is a qualitative approach with case study methods, including in-depth interviews, social media content analysis, and participatory observation. The genealogy reveals fundamental differences between Banda Aceh, which exhibits a tolerance pattern influenced by Sharia law and strict norms, and Kediri, which is more inclusive due to its multicultural interactions. In digital spaces, religious contestation reflects tensions between conservative and progressive groups; Banda Aceh tends to uphold traditional values, while Kediri is more open to interfaith dialogue. The findings indicate that digital spaces have significant potential for fostering religious tolerance, though they are also vulnerable to hate speech and polarization. The future of religious tolerance in both regions will heavily depend on how communities and governments manage digital interactions, as well as educational efforts and policies that promote dialogue and interfaith understanding.

A novel approach for enhancing the mechanical behavior of additively manufactured metal matrix composite structures: Preliminary investigation

Additive Manufacturing is a promising technique for expanding the boundaries of Metal Matrix Composites. In this study, Powder Bed Fusion (PBF) technique, employing Electron Beam as the heat source, was used to print Ti6Al4V metal matrix in different geometric shapes with a new approach for MMC fabrication. Yttria Stabilized Zirconia (YSZ) powder was then incorporated into these pattern shapes, compacted, and sintered to bind the powder particles together. The findings showed that successful sintering was achieved, resulting in the formation of a flexible interface region, with the circular design achieving the best interface region among all pattern designs. Regarding the mechanical performance evaluation of the developed Metal Matrix Composites, it was found that the mechanical strength was significantly increased with the hexagonal and circular patterns achieving the best results. Future research should pay more attention to further design development for the metal matrix model to achieve outstanding performance and create a new field for Metal Matrix Composites using the developed method.

NEURD offers automated proofreading and feature extraction for connectomics.

We are now in the era of millimeter-scale electron microscopy (EM) volumes collected at nanometer resolution. Dense reconstruction of cellular compartments in these EM volumes has been enabled by recent advances in Machine Learning (ML). Automated segmentation methods produce exceptionally accurate reconstructions of cells, but post-hoc proofreading is still required to generate large connectomes free of merge and split errors. The elaborate 3-D meshes of neurons in these volumes contain detailed morphological information at multiple scales, from the diameter, shape, and branching patterns of axons and dendrites, down to the fine-scale structure of dendritic spines. However, extracting these features can require substantial effort to piece together existing tools into custom workflows. Building on existing open-source software for mesh manipulation, here we present "NEURD", a software package that decomposes meshed neurons into compact and extensively-annotated graph representations. With these feature-rich graphs, we automate a variety of tasks such as state of the art automated proofreading of merge errors, cell classification, spine detection, axon-dendritic proximities, and other annotations. These features enable many downstream analyses of neural morphology and connectivity, making these massive and complex datasets more accessible to neuroscience researchers focused on a variety of scientific questions.

Forehead shape analysis following surgical and conservative treatment in metopic synostosis: a 3D photogrammetry analysis.

The aim of this study is to describe and compare head shape in surgically and conservatively treated patients using 3D photogrammetry. A retrospective review (2017-2020) of consecutive patients with isolated metopic synostosis based on 3D photogrammetry was conducted at the age of 4 years old. Images were aligned using a healthy age-matched template, and mean head shapes were reconstructed to evaluate shape development. A comparative sub-analysis based on phenotype was performed between patients that have been treated surgically and conservatively. 44 patients with isolated metopic synostosis were included: 22 received conservative treatment and 22 underwent fronto-orbital advancement. At 4 years of age the surgical group showed retrusion of the complete frontal area, while the conservative group showed a slight frontal prominence. Both groups showed temporal depression with respect to the control. In the sub-analysis, a similar degree of temporal depression was observed between surgical and conservative treatment. Head shape patterns showed considerable similarity across all severity phenotypes. This study shows a deviation in forehead shape from normal controls in patients with metopic synostosis following both surgical and conservative treatment by the age of 4 years. Comparison between surgical and conservative treatment shows a similar degree of temporal depression, a slight prominence in the center of the forehead in the conservative group, and retrusion of the entire frontal area in the surgical group. This observed difference is of considerable similarity across all severity types. III.

Aerodynamic Noise Simulation of a Super-High-Rise Building Facade with Shark-Like Grooved Skin.

The wind-driven aerodynamic noise of super-high-rise building facades not only affects the experience of use inside the building but also reduces the life cycle of building facade materials to some extent. In this paper, we are inspired by the micro-groove structure of shark skin with damping and noise reduction properties and apply bionic skin to reduce the aerodynamic noise impact of super-high-rise buildings. The aerodynamic noise performance of smooth and super-high-rise building models with bionic grooves is simulated via CFD to investigate the noise reduction performance of different bionic groove patterns, such as I-shape, ∪-shape, V-shape, and ∩-shape patterns, and their corresponding acoustic noise reduction mechanisms. This study showed that the bionic shark groove skin has a certain noise reduction effect, and the I-shaped groove has the best noise reduction effect. By applying bionic skin, the aerodynamic noise of super-high-rise buildings can be effectively reduced to improve the use experience and environmental quality of the buildings and provide a new research idea and application direction for the aerodynamic noise reduction design of building facades.

Genetic diversity during selective sweeps in non-recombining populations.

Selective sweeps, resulting from the spread of beneficial, neutral, or deleterious mutations through a population, shape patterns of genetic variation at linked neutral sites. While many theoretical, computational, and statistical advances have been made in understanding the genomic signatures of selective sweeps in recombining populations, substantially less is understood in populations with little/no recombination. We present a mathematical framework based on diffusion theory for obtaining the site frequency spectrum (SFS) at linked neutral sites immediately post and during the fixation of moderately or strongly beneficial mutations. We find that when a single hard sweep occurs, the SFS decays as 1/ x for low derived allele frequencies ( x ), similar to the neutral SFS at equilibrium, whereas at higher derived allele frequencies, it follows a 1/ x 2 power law. These power laws are universal in the sense that they are independent of the dominance and inbreeding coefficient, and also characterize the SFS during the sweep. Additionally, we find that the derived allele frequency where the SFS shifts from the 1/ x to 1/ x 2 law, is inversely proportional to the selection strength: thus under strong selection, the SFS follows the 1/ x 2 dependence for most allele frequencies, resembling a rapidly expanding neutral population. When clonal interference is pervasive, the SFS immediately post-fixation becomes U-shaped and is better explained by the equilibrium SFS of selected sites. Our results will be important in developing statistical methods to infer the timing and strength of recent selective sweeps in asexual populations, genomic regions that lack recombination, and clonally propagating tumor populations.

How Shape Perception Works, in Two Dimensions and Three Dimensions

The ventral visual pathway transforms retinal images into neural representations that support object understanding, including exquisite appreciation of precise 2D pattern shape and 3D volumetric shape. We articulate a framework for understanding the goals of this transformation and how they are achieved by neural coding at successive ventral pathway stages. The critical goals are (a) radical compression to make shape information communicable across axonal bundles and storable in memory, (b) explicit coding to make shape information easily readable by the rest of the brain and thus accessible for cognition and behavioral control, and (c) representational stability to maintain consistent perception across highly variable viewing conditions. We describe how each transformational step in ventral pathway vision serves one or more of these goals. This three-goal framework unifies discoveries about ventral shape processing into a neural explanation for our remarkable experience of shape as a vivid, richly detailed aspect of the natural world.

104 Non-invasive pregnancy diagnosis in Holstein dairy cows using computer vision analysis of thermal images

Abstract Thermal visualization of Holstein dairy cattle skin can be indicative of the pregnancy state (cyclic or pregnant) of the cow by observing the size and shape of skin thermal patterns. However, visual assessment of skin thermal patterns can be subjective and laborious. Further, infrared thermography implementation on-farm requires automated analysis to be feasible for dairy producers. The objectives of this study were to implement a machine learning convolutional neural network (CNN) to detect features in thermal images associated with pregnant (Pregnant) and non-pregnant (Cyclic) and to evaluate the accuracy of pregnancy diagnosis in dairy cows. A total of 938 images from 18 Pregnant cows and 982 images from 18 Cyclic were used to build the CNN model, and 120 images from Pregnant (60 images) and Cyclic (60 images) dairy cows were used to validate the model. Pregnant cows were confirmed to be pregnant 90 d after insemination via transrectal ultrasonography. Cyclic cows were confirmed to be non-pregnant using follicular dynamics and corpora lutea presence via transrectal ultrasonography. Images were recorded using a T620s infrared camera at 640 × 480 (307,200) to train the CNN model and images from an E40 FLIR camera at 320 x 240 (76,800 pixels) were used for the validation test. The CNN model was created using TensorFlow in Google Colab to binary classify images into Pregnant or Cyclic using a single output neuron (1: Pregnant and 0: Cyclic) with different Epochs (10, 25, and 100). The diagnosis accuracy (acc) was 0.72 with a validation accuracy (val_acc) of 0.41 for 10 Epochs, acc 0.76 with val_acc 0.37 for 25 Epochs, and acc 0.80 with val_acc 0.63. The acc and val_acc of the training model and validation test were optimized when using images from the T620s exclusively (Epochs 10: acc = 0.70 and val_acc = 0.64; Epoch 25: acc = 0.74 and val_acc = 0.70; Epoch 100: acc = 0.81 and val_acc = 0.80). Greater resolution of thermal images was proven to increase the accuracy of pregnancy diagnosis (307,200 compared with 76,800 pixels) and the greater number of Epoch used to train the model. Machine learning algorithms can diagnose pregnancy using thermal images with an acceptable evaluation accuracy (> 0.70).

Carapace Morphology Variations in Captive Tortoises: Insights from Three-Dimensional Analysis.

The carapace morphology of tortoises is a crucial characteristic used for species identification, with features such as shell shape, roughness, and color patterns varying among species. Understanding this morphological diversity is valuable not only for taxonomic classification but also for more specialized clinical approaches. This study investigated the morphological differences in the shells of Leopard tortoises (Stigmochelys pardalis), African spurred tortoises (Centrochelys sulcata), and Greek tortoises (spur-thighed tortoises; Testudo graeca) raised in captivity. Using 3D scanners, the carapaces were modeled, and a 3D geometric morphometric method was employed to analyze shape variations and dimensional features, with landmarks applied automatically. Among the species studied, African spurred tortoises had the largest carapace size. Principal component analysis (PCA) identified PC1 and PC3 as critical factors in distinguishing between species based on morphological characteristics. Positive PC1 values, associated with a shorter carapace height, indicated a flatter or more compact shell shape. A higher PC3 value corresponded to a raised shape at the back of the shell, while a lower PC3 value indicated a raised shape at the front. Specifically, Leopard tortoises exhibited a higher carapace shape than the other species, while African spurred tortoises had shorter carapaces. An allometric effect was observed in the carapaces, where smaller specimens tended to be proportionately higher-domed, whereas larger shells displayed a lower height in shape. These findings highlight the significance of shape variations in tortoise shells, which emerge during adaptation and have important implications for taxonomy and clinical practice. Such differences should be carefully considered in veterinary care and species identification.

Photocatalytic and antibacterial activity properties of Ti surface treated by femtosecond laser–a prospective solution to peri-implant disease

Laser texturing seems to be a promising technique for reducing bacterial adhesion on titanium implant surfaces. This work aims to demonstrate the possibility of obtaining a functionally orientated surface of titanium implant elements with a specific architecture with specific bacteriological and photocatalytic properties. Femtosecond laser-generated surface structures, such as laser-induced periodic surface structures (LIPSS, wrinkles), grooves, and spikes on titanium, have been characterised by XRD, Raman spectroscopy, and scanning electron microscopy (SEM). The photocatalytic activity of the titanium surfaces produced was tested based on the degradation effect of methylene blue (MB). The correlation between the photocatalytic activity of TiO2 coatings and their morphology and structure has been analysed. Features related to the size, shape, and distribution of the roughness patterns were found to influence the adhesion of the bacterial strain on different surfaces. On the laser-structurised surface, the adhesion of Escherichia coli bacteria were reduced by 80% compared to an untreated reference surface.

Computation of drag coefficient for real vegetation in wetlands

The flow characteristics in wetlands and vegetated channels are depend on the physical structure, density, and pattern of vegetation. Estimating average velocity in vegetated wetlands requires an accurate determination of the drag coefficient. The innovation of this research lies in calculating the drag coefficient while considering the pattern shape, plant flexural rigidity, and vegetation structure. Laboratory experiments were conducted in a rectangular flume using a parallel pattern of Eleocharis plants at three densities: low, medium, and high, with discharge rates of 18.2, 23.7, and 28.8 L/s, respectively. Comparative analysis revealed that the equation proposed by Kothyari et al. (2009) [23] is just suitable for determining the drag coefficient on rigid cylinders with a staggered pattern and it should be improved for real vegetation with different pattern. A comprehensive equation was developed for real wetland vegetation, incorporating a new pattern coefficient for pattern shape (ζpp) and correction factor (η) to consider plant flexural rigidity and vegetation structure. The results demonstrate that this equation accurately predicts the drag coefficient (RMSE = 0.127, MAE = 0.107, and R2 = 0.9059) in channels with real vegetation with parallel and staggered patterns.

Command of three-dimensional solitary waves via photopatterning.

Multidimensional solitons are prevalent in numerous research fields. In orientationally ordered soft matter system, three-dimensional director solitons exemplify the localized distortion of molecular orientation. However, their precise manipulation remains challenging due to unpredictable and uncontrolled generation. Here, we utilize preimposed programmable photopatterning in nematics to control the kinetics of director solitons. This enables both unidirectional and bidirectional generation at specific locations and times, confinement within micron-scaled patterns of diverse shapes, and directed propagation along predefined trajectories. A focused dynamical model provides insight into the origins of these solitons and aligns closely with experimental observations, underscoring the pivotal role of anchoring conditions in soliton manipulation. Our findings pave the way for diverse fundamental research avenues and promising applications, including microcargo transportation and optical information processing.

Aplikasi Material Rotan Pada Perancangan Table Lamp

Rattan is one of the main materials in simple crafts and a material for interior furniture items. In Indonesia, rattan is very abundant and is one of the largest rattan producing countries in the world. On the other hand, this rattan material is very popular with furniture entrepreneurs because rattan can be made into creative products that have features both in terms of function and aesthetics.. Furniture produced includes chairs, tables, and decorative products. The application of rattan in making table lamps is found on the hood which uses rattan material with a four-axis rattan weaving technique. This technique Arrange the woven material in 4 different directions and will produce a woven pattern with more holes with hexagonal and octagonal pattern shapes. On the lamp body is made of wood glued to the sides of the wood. So the process of making this table lamp is through material observation and experimentation. The purpose of this design is to increase consumer attractiveness to interior needs. The application of rattan material in the design of table lamps produces products that are not only aesthetically pleasing, but also pay attention to aspects of sustainability and functionality needs.

Mixed-mode crack-tip stress intensity factors measurements by caustics method: A comparison between low and high loading rate conditions

Mixed-mode crack-tip stress field is different in low and high loading rate conditions, resulting in different mixed-mode stress intensity factors (SIFs) measurements. How to correctly measure mixed-mode SIFs in different loading rate conditions is of critical importance. To this end, mixed-mode SIFs are measured and compared by optical caustics method with high-speed photography, specifically by the interpretation of crack-tip optical image, i.e., caustics pattern which reflects crack-tip stress field. Different mixed-mode caustics patterns in shape are observed in drop weight and blast loading conditions, indicating that corresponding crack-tip stress field and mixed-mode SIFs measurements are different. Under drop weight loading, mixed-mode caustics patterns are consistent with the classical caustics interpretation for SIFs measurements, while those under reflected P wave loading in blasts are not consistent. Therefore, a modified mixed-mode caustics interpretation is proposed and verified to be available for SIFs measurements in blast loading condition. Finally, underlying reasons for different mixed-mode SIFs measurements in low and high loading rate conditions are discussed, and it is concluded that in low loading rate condition, a longer loading time results in crack-tip K-dominated stress field which is suitable for the classical caustics interpretation, while in high loading rate condition, the loading time is too short to form K-dominated stress field in the crack tip, hence a modified caustics interpretation is necessary. This paper benefits correct applications of caustics method to mixed-mode SIFs measurements in different loading rate conditions.