Regular Shape Research Articles

Localized corrosion behavior on a heterogeneous surface involving multicomponent reactive transport and morphology evolution

AbstractLocalized corrosion sometimes brings about unanticipated and catastrophic damages in petrochemical pipelines and pressure vessels. For localized corrosion modeling, multicomponent reactive transport and corrosion morphology evolution are two arduous problems that involve multi–physical‐(electro) chemical processes along with multi–temporal and spatial scales. In this study, the lattice Boltzmann method (LBM) is employed to shed some light on the evolution of localized corrosion on a heterogeneous surface focusing on the effects of electrolyte ohmic resistance and diffusion. The corrosion pit is always initiated at the junction of anode and cathode sites; however, quite different morphologies are prompted under ohmic control or ohmic‐diffusion control. Under ohmic control, the pit propagates along the interface of the anode and cathode. Under ohmic‐diffusion control, the pathway of reactive species is broadened, and the corrosion morphology is developed into a more regular shape, like a flattened semicircle in 2‐D modeling. This work presents the huge potential of LBM in long‐term corrosion modeling.

DEVELOPMENT AND EVALUATION OF CYCLODEXTRIN NANOSPONGES-BASED TOPICAL FORMULATION OF TAZAROTENE

Objective: Tazarotene is used as a topical retinoid for the treatment of acne, psoriasis and sun-damaged skin. But its topical formulation has many side effects, including itching, burning, dryness, redness, stinging, rash blistering, skin discoloration, peeling at the site of application and low bioavailability. The present study focuses on the reduction of side effects and enhancement of solubility and topical bioavailability of tazarotene by using cyclodextrin-based nanosponges. Methods: Nanosponge of tazarotene were prepared by lyophilization method. The physiochemical characterization of plain nanosponges and drug-loaded nanosponges were performed using Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and X-ray Diffractometer (XRD) studies. The drug-loaded nanosponges were incorporated into a carpool-based gel formulation. The prepared formulation was evaluated for viscosity, dissolution and stability. FTIR, DSC and XRD studies confirmed the formation of inclusion complex of tazarotene with nanosponges. Results: The particle size of the drug-loaded nanosponges was found to be in the range of 156.72 to 163.48 nm. Transmission Electron Microscopy (TEM) images revealed the regular spherical shape of both the nanosponges that are unaffected even after drug encapsulation. The pH of the gel formulations was found to be in the range of 5.86 to 6.46. The gel formulation resulted in the diffusion of drug in controlled manner for up to 24 h. The in vitro dissolution studies revealed that nanosponges-based topical formulation had better results than the marketed product. Conclusion: Thus, the study showed that nanosponge-based gel formulation can be a possible alternative to conventional formulations of tazarotene with enhanced bioavailability and skin retention characteristics for topical application.

Integrating Public Perception and Quantitative Metrics for Improved Urban Park Planning in Isfahan, Iran

This study delves into the intricate realm of public perception regarding urban parks, aiming to uncover key factors influencing this perception and offer insights for urban planning and park management in Isfahan City, Central Iran. A comprehensive survey was conducted across 63 urban parks, gathering subjective feedback from park visitors on park size, vegetation, and exposure to external disturbances. Objective metrics were the area of the park, the mean and stdev of the Sentinel-2 NDVI as measures of vegetation density and diversity, respectively, distance to other parks and the park perimeter-to-area ratio. Linear and non-linear regression analysis between subjective feedback and objective metrics revealed that satisfaction peaks in parks with sizes of 15 ha or more. Higher vegetation density maximizes satisfaction. Parks with simpler, more regular shapes tend to offer a greater sense of freedom from external disruptions. According to the Generalized Additive Model model (R2= 0.737, explained deviance = 77.1%), lush and healthy vegetation is often associated with attractive and inviting parks, especially in parks with simpler, more regular shapes that minimize the exposure to (noise and visual) disturbances. Such green and circular park designs can guide urban planners and managers in creating inviting and user-friendly parks, aligning with public expectations.

Investigation of CuO/ITO Photoelectrode Fabricated by PVD for Efficient Photoelectrochemical Water Splitting and Hydrogen Evolution

ABSTRACTHydrogen and renewable fuels were generated using cost‐effective and efficient electrocatalysts for water splitting. In this work, a CuO‐based photocathode is used for the water splitting to generate hydrogen energy by PVD technique. The XRD analysis reveals the deposition of CuO thin film on ITO substrates, which is monoclinic. The XRD and LSV analysis of CuO confirmed the type of semiconductor and observed to be P‐type semiconductor. SEM study of CuO confirmed the shape, morphology to be a circular and regular shape. The grain size of deposited CuO thin film was found to be 18 nm. The absorption and transmission of CuO thin film were observed through UV spectroscopy analysis and were found to be better photocatalyst in visible range 415–425 nm. The transmittance of the prepared thin film was noted to be maximum 7.6% in the UV range (280–300 nm). The band gap was also measured employing the Tauc plot and found to be 2.98 eV, which is most favorable for water splitting application. FTIR study showed the stretching, vibration, and the functional group of the deposited CuO thin film; the broad band of stretching of Cu‐O in monoclinic CuO was observed at the range of 500–700 cm−1, and further peaks were also noted at the range of 1500–1600 cm−1. The linear sweep voltammetry (LSV) of CuO thin film was calculated in the absence of solar spectra and the presence of solar spectra and observed to be enhanced in current under solar spectra. The solar light to hydrogen emission percentage (STH %) of CuO through LSV was observed to be 2.04% under solar spectra. The low Nyquist curve of blank ITO and CuO‐coated ITO substrate via electrochemical impedance spectroscopy (EIS) analysis was observed, which confirmed the enhancement of EIS of CuO‐coated ITO. The hydrogen generation rate was also calculated by electrochemical cell and observed to be 5325.21 mol g−1 for 6 h.

Design and assessment of an adapted absorber solar air collector tailored for sustainable drying applications

The design of a relevant solar air collector (SAC) is imperative to make the drying industries self-reliant and sustainable in terms of energy. However, the literature doesn’t describe the coherent design assessment of SAC, and its viability for a drying system provided the scale-up opportunity for commercial applications. Hence, the present work was devoted to estimating the heat load for a particular drying condition, a methodological understanding of SAC design, and an investigation of the performance of the newly developed solar collector. The essential design criteria were the moisture content of fresh and intended dried items, physical attributes of items, dryer capacity, preferred drying temperature, projected drying duration, required air speed (based on dryer type), and local climate (solar radiation, ambient temperature and relative humidity). The regular semi-hexagonal shape aluminium (Al) sheet was chosen to introduce air turbulence while maximizing the surface area available for heat transfer. The regular semi-hexagonal absorber was outfitted with helical springs to generate air turbulence and augment heat transfer. A double glazing (polycarbonate) of 5 mm apart was mounted to impede radiation heat loss. Three successive days of the experimental study showed that the average temperature increases of air passing through SAC were 36.02 °C, 37 °C, and 39.2 °C. The optimal tilt angle with the horizontal surface was found to be 35° in a south-facing direction for the month of January. The highest energy efficiency was found to be 40.5 %, while the lowest was found to be 24.73 %. The sustainability index of the SAC was found to be 1.02. The experimental results clearly demonstrate that the designed SAC was capable of supplying adequate heat energy (at the minimum of 155.86 W/hr.) to meet the necessary heat load (125.82 W/hr.) for agro-products drying at the designed capacity.

A modified self-micro emulsifying liposome for bioavailability enhancement of quercetin and its biological effects

Quercetin (QT) is a chief dietary flavonoid with a myriad of health benefits, however, its poor solubility and low bioavailability restrict its food application. Thus, the present study aimed at enhancing its solubility using a modified self-micro emulsifying system (QT-TPGS-QS). The stability of liposome was assessed via monitoring of its particle indexes (size, zeta potential, PDI, stability towards in-vitro digestion, drug release, and encapsulation efficiency). Further, antibacterial and cellular antioxidant potential of liposomes were determined. QT-TPGS-QS exhibited good optical clarity with a loading ratio of 2.1%. The liposome showed uniform spherical and regular shape (<100 nm) with a QT release rate of 85.61% ± 0.32% in simulated in-vitro digestion. QT-TPGS-QS demonstrated superior antibacterial activity compared to QT alone against Escherichia coli, Staphylococcus aureus, and Salmonella. In-vitro antioxidant evaluation confirmed that the QT-TPGS-QS exhibited a significantly higher free radical scavenging ability than QT alone. Cellular assay confirmed that QT-TPGS-QS (15 μg/mL) exhibited a good protection effect on oxidative stress induced by H2O2. Catalase (CAT) and glutathione peroxidase (GSH-Px) levels were significantly upregulated, concurrent with a reduction of malondialdehyde (MDA) suggesting that QT-TPGS-QS might be effective in inhibiting the production of intracellular reactive oxygen species (ROS), and to be considered as food additive or in nutraceuticals.

Penetration of Non-Adhesive Gel-like Embolic Materials During Dural Vessels Embolization According to Characteristics of Tantalum Powder

Tantalum powder is included in the composition of Non-Adhesive Gel-like Embolic Materials (NAGLEMs) for X-ray opacity. The duration of X-ray opacity during embolization is primarily associated with the particle size, which differs in the most used NAGLEMs—ONYX (Medtronic) and SQUID (Balt). NAGLEMs are widely used for the embolization of branches of the middle meningeal artery (MMA) in patients with chronic subdural hematomas (CSDHs). Considering the size (5–15 microns) of the target dural vessels, we assumed that not only the viscosity of NAGLEMs, but also the size and shape of tantalum granules may be important for the penetration of these gel-like embolic agents and determine their behavior. A notable discrepancy in size was observed. The medium-sized granules in the SQUID 18 sample (0.443 ± 0.086 microns, M ± SD) were found to be approximately ten times smaller than the tantalum granules in the ONYX 18 sample (5.2 ± 0.33 microns, M ± SD).Tantalum granules in SQUID 18 have a regular spherical shape; in ONYX 18 they have an irregular angular shape. When comparing the behavior of gel-like embolic agents of the same viscosity during MMA embolization in patients with CSDHs (an average age of 62.2 ± 14.3 years) in the group where SQUID 18 (n = 8) was used, the gel-like embolic agent in dural vessels demonstrated significantly greater penetration ability compared with the group where ONYX 18 (n = 8) was used. Accordingly, not only the viscosity of NAGLEMs, but also the size and shape of tantalum granules can have a significant effect on the penetration ability of gel compositions.

Piezoelectricity and flexoelectricity in biological cells: the role of cell structure and organelles.

Living tissues experience various external forces on cells, influencing their behaviour, physiology, shape, gene expression, and destiny through interactions with their environment. Despite much research done in this area, challenges remain in our better understanding of the behaviour of the cell in response to external stimuli, including the arrangement, quantity, and shape of organelles within the cell. This study explores the electromechanical behaviour of biological cells, including organelles like microtubules, mitochondria, nuclei, and cell membranes. A two-dimensional bio-electromechanical model for two distinct cell structures has been developed to analyze the behavior of the biological cell to the external electrical and mechanical responses. The piezoelectric and flexoelectric effects have been included via multiphysics coupling for the biological cell. All the governing equations have been discretized and solved by the finite element method. It is found that the longitudinal stress is absent and only the transverse stress plays a crucial role when the mechanical load is imposed on the top side of the cell through compressive displacement. The impact of flexoelectricity is elucidated by introducing a new parameter called the maximum electric potential ratio ( ). It has been found that depends upon the orientation angle and shape of the microtubules. The magnitude of exhibit huge change when we change the shape and orientation of the organelles, which in some cases (boundary condition (BC)-3) can reach to three times of regular shape organelles. Further, the study reveals that the number of microtubules significantly impacts effective elastic and piezoelectric coefficients, affecting cell behavior based on structure, microtubule orientation, and mechanical stress direction. The insight obtained from the current study can assist in advancements in medical therapies such as tissue engineering and regenerative medicine.

Optimization of Fuzzy Mathematical Model of Regular Octagon-Shaped Parking Space

In the vigorous development of the city population, there is a need to set up clear dimensions for the parking space. Car parking plays a significant part in the residential apartments and commercial buildings. Roadside parking spaces will create a huge traffic problem if the parking lots are not properly designed. Sometimes, it leads to the accident. Hence, keeping all these causes in mind, the flexible parking space is the necessary of the time. In the proposed research work, the parking space considered in the problem is of a regular octagon shape, and the mathematical model is developed under a fuzzy environment. LINGO Optimization Software is used to solve the mathematical model and MATLAB(Matrix Laboratory) is used to define the fuzzy variable. At the outset, the results will reveal the importance of making the length of the parking lot under fuzzy environment.

Electrically charged black holes in [formula omitted]-Euler–Heisenberg theory

Drawing on the concept of the non-linear dynamics of electromagnetic fields in vacuum in terms of the Euler–Heisenberg system, a static and spherically symmetric black hole solution is derived by coupling the Euler–Heisenberg term and F(R) gravity. In applying the curvature singularity tools, the black hole solution induces a singular behaviour at the centre r=0 while exhibiting a regular shape at high distances. Using the heat capacity (CQ) and the Helmholtz free energy (F), we analyse the thermodynamic stability locally and globally. Furthermore, an investigation is conducted using class tools of Geometrothermodynamics (GTs) features such as Weinhold, Ruppeiner, Hendi–Panahiyan–Eslam–Momennia (HPEM), and Quevedo to identify phase transition points associated with heat capacity, including both physical boundary points (root of the heat capacity) and second critical phase transition points (divergent points of the heat capacity). We have even examined the relevant sparsity of Hawking radiation, showing how the black hole solution behaves as a black body at specific limits. Overall, this study enhances our knowledge of the mergers of a class of non-linear dynamics of electromagnetic fields in a vacuum within F(R) gravity by modelling black hole solutions.

Progressive Collapse Analysis of G+10 RCC Building

This study important of the progressive collapse that final damage of the structure is not similar as the initial collapse of structure. The key parameters used story displacement in eleven-storey building of regular shape that has modelled and analyzed by the ETABS 2018 software by using the Indian standard codes. Then for the calculation of progressive collapse we use U.S General Service Administration (GSA 2016) guidelines. The demand capacity ratio (DCR) values of the neighboring member are taken into account after the damage the DCR values for regular structure must be with in (2). In this study the progressive collapse is considered in three different cases that is at corner, interior and at exterior columns.

Self-Assembly of Cyclic-Bending Collagen Fibrils by Polyimide Films.

The cyclic-bending morphologies of the fibrils formed by the self-assembly of type I collagen (Col) are closely related to the mechanisms of various diseases. Therefore, studies that allow the self-assembly of Col molecules to form cyclic-bending fibrils in vitro are vitally important. In this study, we successfully achieved the cyclic-bending shapes (specifically, a regular hexagonal shape) of Col molecules by controlling the steric structures of polyimide (PI) molecular chains through the film formation process. Specifically, when a single layer of PI film was baked, the PI molecular chains within the film bent in the direction parallel to the substrate surface plane. Repeating the layering and baking processes resulted in 3D structures of the PI molecular chains, which were oriented in the direction perpendicular to the substrate surface plane. This three-dimensional bending would result from the PI molecular chain interactions between the upper and lower layers. When the Col molecules were reacted on these film surfaces, they recognized the structures of the PI molecular chains and self-assembled to form cyclic-bending Col fibrils. Especially, in PI films subjected to three cycles of layering and baking, hemicircular-shaped Col fibrils were observed to be regularly arrayed. Additionally, these regularly cyclic-bending fibrils were aligned in the uniaxial direction through a uniaxial rubbing treatment of the PI films. This successful research is significant both as a method for controlling the morphologies of Col fibrils and as a study that explores the biomedical implications of Col fibril cyclic-bending in the living body.

MATHEMATICAL MODELLING OF SURVIVAL IN LOW GRADE GLIOMAS AT MALIGNANT TRANSFORMATION WITH XGBOOST

Abstract AIMS To develop non-linear machine learning models using the XGBoost algorithm to predict a continuous (overall survival (OS) and a binary survival outcome (OS &amp;gt; 5 years) using clinical, molecular and genetic, and radiomic data. METHOD Patients with LGGs treated at a single institution (2005-2020) with histology and MRIs at the time of malignant transformation (MT) were retrospectively included in this study. MRIs underwent in-house tumour segmentation pipeline with radiomic feature extraction of whole-tumour, enhancing, non-enhancing and oedema components, and masked disconnectome map components. Patients were split into training and testing sets for the development of the survival models, which were assessed with mean absolute error (MAE) and root mean square error (RMSE) for the prediction of OS; and receiver operating characteristics analysis for the prediction of OS &amp;gt; 5 years. RESULTS Of 553 patients, 415 patients were included in the training set and 138 patients in the testing set. The XGB Regressor model was able to predict overall survival (OS) from the time of malignant transformation (tMRI) with an MAE of 953 days (RMSE: 1163 days). The XGB Classifier model was able to predict the probability of OS &amp;gt; 5 years from tMRI with an accuracy of 64% (sensitivity: 58%, specificity: 70%). Age, IDH1 mutation, 1p/19q co- deletion, regularity of tumour shape, and disconnectome-related perilesional components were most predictive of survival outcome. CONCLUSION This study has investigated the predictive capabilities of clinical, molecular and genetic, and radiomic data to develop survival analysis models, using XGBoost, to predict OS and OS &amp;gt; 5 years in patients with LGG at tMRI. We corroborate previous findings that age, 1p/19q co-deletion and IDH1 mutation are positive prognosticators for survival. However, further investigation into the radiomics of the disconnectome, especially of the perilesional oedema compartment, presents an intriguing and novel avenue for survival analysis of patients with LGG.

Spray-dried cyclophosphamide-loaded polyhydroxyalkanoate microparticles: design and characterization

Background and purpose: Cyclophosphamide (CP) is a widely used antitumor and immunosuppressive drug, but it is highly cytotoxic and has carcinogenic and teratogenic potential. To reduce adverse effects of CP therapy and the frequency of its administration, the microencapsulation of CP into biodegradable polymeric matrices can be performed. However, according to the literature, only a few polymers were found suitable to encapsulate CP and achieve its’ sustained release. Experimental approach: In this research, spray-dried cyclophosphamide-loaded poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) microparticles were prepared and characterized in terms of their average hydrodynamic diameter, polydispersity index, surface morphology, zeta potential, encapsulation efficiency, drug loading, thermal properties and cytotoxicity against 3T3 cells. Key results: The obtained CP-loaded microparticles had a regular spherical shape, uniform size distribution with an average diameter of 4.21±0.04 μm and zeta potential of -34.2±0.2 mV. The encap­sulation of cyclophosphamide into the PHBV matrix led to a decrease in melting and degradation tempe­ratures and an increase in diameter, glass transition and cold crystallization temperatures compared to blank microparticles. Moreover, microencapsulation of cyclophosphamide lowered its cytotoxicity compared to the pure drug: the number of dead cells in the culture decreased by 28 %, while their metabolic activity increased by 20 %. The cumulative in vitro drug release studies showed a gradual release of CP up to 18 days, so the obtained microparticle formulation can be used as a sustained-release cyclophosphamide delivery system. Conclusion: In this research, a novel cyclophosphamide-loaded platform based on PHBV micro­particles was established and characterized. Overall, this study offers promising prospects for cancer therapy in the future.

Grid Optimization of Free-Form Spatial Structures Considering the Mechanical Properties

In recent years, the application of free-form surface spatial grid structures in large public buildings has become increasingly common. The layouts of grids are important factors that affect both the mechanical performance and aesthetic appeal of such structures. To achieve a triangular grid with good mechanical performance and uniformity on free-form surfaces, this study proposes a new method called the “strain energy gradient optimization method”. The grid topology is optimized to maximize the overall stiffness, by analyzing the sensitivity of nodal coordinates to the overall strain energy. The results indicate that the overall strain energy of the optimized grid has decreased, indicating an improvement in the structural stiffness. Specifically, compared to the initial grid, the optimized grid has a 30% decrease in strain energy and a 43.3% decrease in maximum nodal displacement. To optimize the smoothness of the grid, the study further applies the Laplacian grid smoothing method. Compared to the mechanically adjusted grid, the structural mechanical performance does not significantly change after smoothing, while the geometric indicators are noticeably improved, with smoother lines and regular shapes. On the other hand, compared to the initial grid, the smoothed grid has a 21.4% decrease in strain energy and a 28.3% decrease in maximum nodal displacement.

Deep Learning Method Applied to Autonomous Image Diagnosis for Prick Test.

The skin prick test (SPT) is used to diagnose sensitization to antigens. This study proposes a deep learning approach to infer wheal dimensions, aiming to reduce dependence on human interpretation. A dataset of SPT images (n = 5844) was used to infer a convolutional neural network for wheal segmentation (ML model). Three methods for inferring wheal dimensions were evaluated: the ML model; the standard protocol (MA1); and approximation of the area as an ellipse using diameters measured by an allergist (MA2). The results were compared with assisted image segmentation (AIS), the most accurate method. Bland-Altman analysis, distribution analyses, and correlation tests were applied to compare the methods. This study also compared the percentage deviation among these methods in determining the area of wheals with regular geometric shapes (n = 150) and with irregular shapes (n = 150). The Bland-Altman analysis showed that the difference between methods was not correlated with the absolute area. The ML model achieved a segmentation accuracy of 85.88% and a strong correlation with the AIS method (ρ = 0.88), outperforming all other methods. Additionally, MA1 showed significant error (13.44 ± 13.95%) for pseudopods. The ML protocol can potentially automate the reading of SPT, offering greater accuracy than the standard protocol.

Analysis of Morphologic Classification System for Acute Promyelocytic Leukemia and Its Correlation with Laboratory Tests and FLT3-ITD Mutation

To establish a morphologic classification system for characterizing blast cells in patients with acute promyelocytic leukemia (APL) and analyze the correlation of different APL morphologic characteristics with conventional tests and genetic variants. Based on the morphological characteristics of APL blast cells, a classification system of 14 categories was established to characterize the inter- and intra-individual cellular morphological heterogeneity of patients. The classification system was used for the morphological analysis of 40 APL patients, and the classification results were statistically analyzed with the patients' conventional test indexes and gene variant characteristics to analyze the correlation of different APL blast cell morphological features with conventional test indexes and gene variants. In the FLT3-ITD mutation-positive group, there were significantly fewer cells with regular nuclear shape, hyper granularity, and missing Auer rods (category 1) than in the FLT3 mutation-negative group (P < 0.05). The activated partial thromboplastin (APTT) was significantly longer in the group with regular nucleus compared to the group with irregular nucleus (P < 0.05). In the hypo-granular group, the APTT was also significantly longer compared to the hyper-granular group (P < 0.01), and the proportion of myeloid blast cells was relatively lower (P < 0.05). The peripheral blood white blood cell counts, D-dimer, lactate dehydrogenase and proportion of bone marrow blast cells were significantly higher in the Auer rods (-) group than Auer rods increasing group (all P < 0.05). The newly established morphologic classification system in this study can objectively characterize different types of APL blast cells, which helps to better assess the intra- and inter-individual heterogeneity of APL blast cells, and further use in accurately analyzing the correlation of morphological phenotypes with biological properties of APL.

A facile method for patterned assembly of nanoparticles using SAM-guided solvent dewetting

The directed assembly of functional nanoparticles (NPs) into desired geometries is crucial for various NP-based devices and applications. Over the past two decades, numerous bottom-up and top-down approaches have been reported for achieving this goal. In this study, we employed a bottom-up approach using a capillary-driven self-assembled monolayer (SAM)-defined template-assisted self-assembly of silver nanocubes (SNCs) and nanodiamonds (NDs). First, different SAM patterns were created on a gold-coated Si substrate using microcontact printing. Upon immersion of the SAM-patterned substrates in the NP solution, the SAM patterns guide the solvent to specific regions during drying. The directed solvent carries the NPs (SNCs and NDs) into these regions during drying owing to their lower energy state in the solvent compared with the SAM regions. Subsequently, the solvent deposits the NPs in these regions because of their interactions with the substrate. Micron-sized lines and rectangular patterns are explored to observe successful NP assembly. The density of the assembled SNCs depends on their concentration in the solvent, with higher concentrations resulting in densely packed assemblies. This effect is not observed for the NDs because of the differing regular and irregular shapes of the SNCs and NDs. This process can be extended to other NPs with suitable solvents and SAMs.

Fixed-wing UAV obstacle avoidance algorithm based on real terrain

Abstract This paper presents an obstacle avoidance algorithm for UAVs based on real terrain constraints. The common obstacle avoidance algorithm often abstracts the obstacle as a sphere or a circle or studies the UAV’s two-dimensional obstacle avoidance on a raster map. With the development of fixed-wing UAVs, UAVs have longer and longer time in the air, longer and longer range, and the low-altitude environment they face is often difficult to simulate with simplified regular shape. Thus, this paper constructs the UAV flight terrain environment using open elevation data and designs an obstacle avoidance algorithm accordingly. When the UAV is tracking the track point, it can better control the UAV to avoid obstacles and fly to the target track point.

On the mechanical behavior of polymeric lattice structures fabricated by stereolithography 3D printing

AbstractThe utilization of 3D printing technology has transformed the possibilities for design adaptability and manufacturability. This study delves into the mechanical response and energy absorptivity of resin‐based lattice structures when subjected to compression, specifically examining structures fabricated from Tough 2000 (ductile) and Rigid 10K (brittle) resin materials using a stereolithography 3D printer. The analysis encompasses various types of lattice designs (such as cubic‐primitive, circular, triangular, and hexagonal), gradient structures, and combined shape configurations with varying strut dimensions. The primary objective is to provide significant findings regarding the compressive performance of these resin lattice structures produced through 3D printing. Analysis results show that graded and combined lattice designs have better compressive behavior compared to regular shapes with the same strut thickness. In addition, and for strut thickness of 0.5 mm, combined lattice designs show better energy absorption capabilities compared to regular shapes.