Angle Method Research Articles

Incident angle optimization with multiple conflicting objectives based on BP-MOPSO in oblique laser interferometry

The oblique incident phase-shifting interferometric measurement method is an effective technique for assessing gear tooth form deviation. In the measurement process, the tooth flank incident angle is a crucial factor determining the quality of interferograms. Addressing the challenge in traditional optical path design, where the selection of the tooth flank incident angle encounters a trade-off among quality features such as measurable tooth area (MTA), interference fringe density (IFD) and interferogram compression ratio (ICR), this paper proposes an optimized method for the tooth flank incident angle. Firstly, a comprehensive evaluation model is established to calculate and analyze the MTA, IFD and ICR of the helical gear. Secondly, by integrating BP neural network and Multi-Objective Particle Swarm Optimization (MOPSO) algorithm, a tooth flank incident angle optimization method is devised to simultaneously optimize the measurement light incident angle γ and the rotation angle of the gear axis β. Finally, simulation analyses and physical experiments are employed to demonstrate the feasibility of the proposed method, compared to before optimization, the pseudocorrelation (PSD) value has increased by an average of 34%, and the residual points have decreased by an average of 80%, confirming its capability to improve quality interferogram and measurement accuracy.

Antimicrobial and antiadhesive activities of secondary metabolites against Bacillus cereus adhesion on PLA 3D printing material: ADMET Tox in silico, molecular docking and molecular dynamic analysis

Bioactive compounds are naturally occurring substances that have the ability to have physiological impacts on the human body. Due to their potential health advantages and their function in preventing and treating a variety of serious health risks, also this substances shown a high antibacterial and antibiofilm activities against bacteria that can affect health. Therefore, the purpose of the current investigation was to test different bioactive compounds (Thymol, Quercetin, Epicatechin gallate, Gallic acid, Coumarin, Caffeic acid, Tannic acid, Apigenin, Carvacrol, Carvone, Beta ionone and Eucalyptol), in order to see there effect against B. cereus. Additionally, the contact angle method was used to examine the influence of those substances on the physicochemical characteristics of PLA 3D printing material and there antiadhesive effect against bacteria studied. According to the antibacterial activities it should be noted that Carvacrol, Tannic acid and Epicatechin gallate were the most active against B. cereus bacteria. The measurements of the contact angle showed a substantial change in the physicochemical characteristics of 3D printing PLA, indicating an improvement in the electron donor character after treatment, and significantly changed the surface hydrophobicity following treatment from hydrophobe PLA to hydrophile PLA after treatement, we can also see that B. cereus can adhere to PLA before treatment but after treatment with bioactive compounds it has become unfavorable which means that our select compounds are indeed active. After the use of computational methods like ADMET analysis, molecular docking and dynamic analysis, it was practical to better understand the physicochemical and pharmacokinetic proprieties, drug-likeness, antibacterial antiadhesive properties of the studied phytocomponents.

Green finance, green development and decarbonization of the energy consumption structure.

Energy plays a crucial role in global economic development, but it also contributes significantly to CO2 emissions. China has proposed a "dual-carbon" goal, and a key aspect to achieving this objective is finding effective ways to promote the decarbonization of the energy consumption structure (DECS). Compared with traditional finance, green finance is pivotal in advancing green and low-carbon development. However, the mechanism through which green finance impacts DECS has not been thoroughly explored. This study employs an enhanced weighted multi-dimensional vector angle method, which is more systematic and scientific, to measure DECS. Then, dynamic panel data from 30 provinces in China spanning the years 2003 to 2020 are used. A double fixed-effects model is applied to investigate the impact of green finance on the DECS and identify potential pathways. Results reveal that green finance significantly enhances DECS, primarily by reinforcing green development. The critical impact pathway involves the promotion of green technology innovation and green industry development. Moreover, the enhancing effect of green finance on the DECS is considerably significant in regions with relatively low government spending on science and technology (S&T), and where the focus is not on the "Atmospheric Ten" policy. The measurement of DECS is innovative, and the conclusions derived from it can offer compelling evidence for various social stakeholders. The government has the opportunity to establish a green financial system, supporting green technological innovation and the development of green industries. This approach can accelerate the DECS and work toward achieving the "double carbon" goal at an earlier date.

Investigation of radial basis function dynamic mesh method with rotation correction based on adaptive background mesh

Strategies to improve the quality, robustness, and efficiency of dynamic mesh deformation are investigated. Radial basis function (RBF) interpolation is used for the background mesh, and volume-weighted interpolation is utilized for the computational mesh. An adaptive background mesh with an octree structure is automatically generated. It is refined according to the resolution near the boundaries and the wall's interior is also covered by mesh which is of sufficient resolution and prevents a negative volume due to large deformations of complex configurations. Secondly, the RBF method based on adaptive background mesh, the RBF interpolation angle method based on adaptive background mesh, and the damping function-RBF interpolation angle method based on adaptive background mesh have been developed. This method is applicable to complex shapes with multiple gaps, ensuring a high-quality mesh and high computational efficiency for large deformations. The numerical validation of the interpolation rotation angles for different RBFs indicates that the CTPS C0 function is suitable for large gradients in the boundary deformation. The RBF interpolation angle method ensures a smoother deformation for rigid and large deformations. The damping function-RBF interpolation angle method ensures mesh orthogonality near the boundary during elastic deformation, improving the boundary layer's quality and deformation robustness. Several examples show that the proposed method improves the mesh quality by about 30% and increases the time consumption by about 10%. In addition, the methods are applicable to rigid/elastic deformation of objects with multiple boundaries.

Steel–aluminum screw–thread pair tightening mechanism and fastening axial force conversion efficiency

During the tightening of bolted connection, the tightening torque of the bolt is converted into its fastening axial force. The magnitude of the fastening axial force significantly affects the reliability and fatigue strength of bolted connections. Herein, a theoretical analysis of the tightening process of bolt connection is conducted using a power exponent hardening constitutive model, and the expressions of the tightening angle–fastening axial force and tightening angle–tightening torque during the tightening process are derived. A fine finite element model of steel–aluminum thread connections that can be used to simulate the actual tightening process considering the detailed thread structure is established. The accuracy of the theoretical formula is verified by finite element method and experiment, respectively. Through finite element simulation and experiment, the correctness of the formula is verified. Further, the conversion efficiency of the fastening axial force of the steel–aluminum screw–thread pair is analyzed by combining finite element analysis and theory. The results show that under the same tightening torque, the conversion efficiency of the fastening axial force can be increased by 6.8%–9.3% by appropriately reducing the friction coefficient of the steel–aluminum threaded connection pair. By controlling the fluctuation range of the friction coefficient, the dispersal error of the fastening axial force can be reduced by 26.9%–36.7%. The angle method is more conducive to improving the connection reliability of the steel–aluminum screw–thread pair than the torque method.

A research report on the phase-domain trajectories of fault recording and their mathematical models

In currently known theories and algorithms of fault recording analysis and application, there is little literature where fault feature parameters are mined deeply from electrical physical quantities themselves. In this report the calculation method of the phase angles of the reference point and sample points is obtained, which ensures the correspondence of the time-domain waveform of digital fault recording with its phase-domain trajectory. The relationship between the initial phase angle of a sinusoid and the position of its trajectory, the characteristics of the trajectories of three-phase short-circuit currents containing dc components and the mathematical models of these trajectories are analyzed. Taking a rectangular wave current and a triangle wave current as example, the characteristics of the trajectories of non-sinusoidal and periodical waveforms containing harmonics are analyzed as well as their mathematical models. The research results show that the relationship between the initial phase angle of a sinusoid and the position of its circular trajectory is definite; the dc components have no impact on the positions of the trajectories of the short-circuit currents, but on their sizes and shapes; the harmonics have an impact on the shapes of the trajectories, and their positions are decided by the initial phase angles of the ac fundamental components in the waveforms. Subsequent study of the algorithm of fault recording analysis will be spread based on the contents in this report.

Thumb Pronation Angle in Thumb Opposition Evaluated by the Nail Tip Angle of Thumb-Ring Finger Opposition.

This study aimed to devise the method for the evaluation of the thumb pronation angle and calculate its reference value. The study was conducted from October 2021 to March 2022, and 600 hands of 300 healthy volunteers were included in this study. The participants were divided into 6 age groups with 50 participants each. In study 1, 12 participants from group 1 were randomly selected, which included 6 male and 6 female participants. We measured the thumb pronation angle using FASTRAK system and the nail tip angle of thumb-ring finger opposition (T-R angle) and also evaluated the relation between them. In study 2, we measured the T-R angle of 600 hands of 300 healthy volunteers. The T-R angle mean (SD) and 95% confidence interval (CI) of each age group were calculated as reference values. The thumb pronation angle was correlated with the T-R angle. The T-R angle mean (SD) and 95% CI of the 6 groups were as follows: group 1, 142.5° (12.4) and 117.7 to 167.3; group 2, 139.9° (10.1) and 119.7 to 160.1; group 3, 142.3° (9.7) and 122.9 to 160.5; group 4, 140.2° (12.6) and 115.0 to 165.4; group 5, 138.3° (11.9) and 114.5 to 162.1; and group 6, 135.4° (13.0) and 109.4 to 161.4. The 95% CI tended to decrease with an increasing age. The T-R angle was a suitable evaluation method for the thumb pronation angle, and it should be evaluated by age groups.

Computational aptamer design for spike glycoprotein (S) (SARS CoV-2) detection with an electrochemical aptasensor

A new bioinformatic platform (APTERION) was used to design in a short time and with high specificity an aptamer for the detection of the spike protein, a structural protein of SARS-CoV-2 virus, responsible for the COVID-19 pandemic. The aptamer concentration on the carbon electrode surface was optimized using static contact angle and fluorescence method, while specificity was tested using differential pulse voltammetry (DPV) associated to carbon screen-printed electrodes. The data obtained demonstrated the good features of the aptamer which could be used to create a rapid method for the detection of SARS-CoV-2 virus. In fact, it is specific for spike also when tested against bovine serum albumin and lysozyme, competitor proteins if saliva is used as sample to test for the virus presence. Spectrofluorometric characterization allowed to measure the amount of aptamer present on the carbon electrode surface, while DPV measurements proved the affinity of the aptamer towards the spike protein and gave quantitative results. The acquired data allowed to conclude that the APTERION bioinformatic platform is a good method for aptamer design for rapidity and specificity.Key points• Spike protein detection using an electrochemical biosensor• Aptamer characterization by contact angle and fluorescent measurements on electrode surface• Computational design of specific aptamers to speed up the aptameric sequence time

The Impact of Interaction between Body Posture and Movement Pattern Quality on Injuries in Amateur Athletes.

Background: this study aimed to examine the impact of interaction between body posture and the quality of movement patterns on injury frequencies in amateur athletes. Methods: The study sample consisted of 89 young amateur athletes. Movement pattern quality was assessed by the Functional Movement Screen (FMS), test and body posture in the frontal plane was assessed by the moire method for the parameters Shoulder Slope Angle, Lower Scapula Protrusion Difference, and Pelvic Tilt Angle. Injury data were collected through completion of the Injury History Questionnaire for the past 12 months. Results: Using cluster analysis, participants were allocated into a either category with good (BPg) body posture or poor (BPp), and using FMS cutoff points (14), either a category of good movement pattern quality (MPg) or poor (MPp). Two-way ANOVA was performed, and the Bonferroni post-hoc test revealed a reduction in injuries among participants from the MPg-BPg group compared to the other three groups (p < 0.05). However, no interaction between factors was revealed. No statistically significant differences were observed among the remaining three groups in the case of injury prevalence (p > 0.05). Conclusions: A combination of proper body posture and high-quality movement patterns is associated with a lower frequency of injuries, without direct interaction between chosen factors, which suggests that they impact injury risk independently. Practicing suitable BP and ensuring high-quality MPs should be regarded as a strategy in injury prevention.

Accurate measurement method of contact angle within a small angle

The wetting phenomenon of liquid on a solid surface is a fundamental natural phenomenon in nature. It has a significant impact on people’s production and life. This paper solves the problem that small-angle wetting cannot be accurately measured by changing the imaging direction and complete auxiliary methods.

Formation and Variability of Barrier Layer in the South Pacific

AbstractThe oceanic barrier layer (BL), dominated by salinity stratification, plays an important role in regulating heat exchange between the mixed layer and the interior ocean. However, the salinity contribution is ignored or underestimated when analyses relying only on temperature threshold methods. Here we introduce the Turner Angle method to quantify the salinity contribution and to obtain relatively accurate BL thickness (BLT), and further to investigate the spatial‐temporal distribution, thickness variation and formation mechanism of the BL in the South Pacific using the updated Argo data during 2005–2021. With the successful usage of this method, we eliminate 41% of the invalid BLs and therefore improve the assessment of the BLs in the South Pacific. Formation of the thick BLs in the South Pacific is attributed to the faster deepening rate of the isothermal layer than the mixed layer. The deepening rate of the isothermal layer is facilitated by subsurface subantarctic mode water while that of the mixed layer is constrained by the subsurface salinity maximum in the South Pacific. On the interannual scale, the BLT in the South Pacific manifests a quasi‐biennial variability, which is closely connected with the variability in the isothermal layer depth and is primarily caused by the anomalous winds driven by the Southern Annular Mode (SAM). The SAM‐related anomalous winds regulate the isothermal layer and further the BL by exerting influences air‐sea heat fluxes and the Ekman layer advection.

Multiple scattering of Bessel beams propagating in advection fog and radiation fog

The Bessel beams scattering of the fog particles were calculated by using the plane beams angle spectrum expansion method, and the effects of the topological charge and the half-conic angle of the Bessel beam on the differential scattering cross-section were analyzed by numerical calculation. Based on the scattering results of a single fog particle by a Bessel beam, by Monte Carlo method, the propagation characteristics of the Bessel beam in fogs with different visibility are simulated, and the effects of the wavelength, topological charge and semi-conic angle of the Bessel beam on transmissivity and reflectivity are analyzed. The studies show the self-healing ability of the Bessel beams, and the propagation distance of the Bessel beam is longer than that of the plane beams in fogs.

Energy-Saving Breakthrough in the Point-to-Point Control of a Flexible Manipulator

This study aims to contribute academically valuable insights into energy-efficient drives for the positioning control of flexible structures. It focuses on the point-to-point (PTP) motion control of a flexible manipulator to suppress residual vibration and reduce driving energy simultaneously. The driving energy for PTP motion is influenced by the initial deflection of the flexible manipulator. Considering this phenomenon, the study proposes a trajectory planning method for the joint angle of a flexible manipulator. In this method, the evaluation function is defined as the sum of drive torques, and its minimization through particle swarm optimization generates an optimal trajectory that minimizes drive energy and suppresses residual vibration. Numerical simulations indicate that significant energy savings can be achieved by actively deforming the manipulator. These simulation results are corroborated by experimental data, which demonstrate the practical applicability and effectiveness of the proposed method.

Evaluasi Sistem Proteksi Penangkal Petir pada Bangunan Power House Bandara Sams Sepinggan

The aim of this research is to solve the lightning protection system (which has been installed and to determine the effectiveness of the lightning protection system. In this research the evaluation method is carried out using data collection and data analysis methods. Data collection methods consist of, observation, measurement, literature study, and Interview. Data analysis consists of, Building needs for lightning protection, Determining protection, Distribution conductors, and Grounding. The evaluation results show that, based on the index stated in the standard (SNI 037014.1-2004) the Main Power House building really needs a lightning protection system. Based on the estimated danger of lightning strikes with a risk level of R=14 (highly recommended), the use of conventional lightning rods with the protection angle method still requires increased protection in the form of the addition of 5 air terminations (splitzers) on the right, left, front, side and back. and the distribution conductor and earth termination (grounding) for both lightning rods as a whole meet the standards.

Nuclear magnetic resonance study on wettability of shale oil reservoir

In order to identify and evaluate reservoir wettability, so as to select suitable mining methods to improve oil recovery, wettability evaluation through one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) technology combined with physical simulation experiments was carried out in this study, and the feasibility of the experimental method was verified by contact Angle method. According to the principle of hydrophilic inorganic content and hydrophobic organic content of shale, the wettability can be evaluated through vacuum self-imbibition oil and self-imbibition water physical simulation experiments combined with 1D NMR technology, that is, total water absorption can be considered as inorganic content, organic content can be obtained by subtracting total water absorption from total oil absorption, and adsorbed oil content can be obtained by subtracting pore volume from total oil absorption. In addition to the wettability measurement by contact Angle method to verify the experimental method, the occurrence ratio of adsorbed oil can also be verified twice by 2D NMR spectrum. The results show that the error between the proportion of adsorbed oil measured by 2D NMR spectrum and that measured by self-imbibition method is within 4%. In the saturated oil-bound water state, the bound water is within the relaxation interval of 1&amp;lt;T1&amp;lt;10 ms and 1&amp;lt;T2&amp;lt;10 ms, and the oil signal is within the relaxation interval of T1&amp;gt;10 ms and T2&amp;gt;10 ms. And the relaxation time of aqueous phase moved to the right compared with that in the saturated water state, the interaction force between water and the pore wall was weakened, showing the characteristics of free fluid, and the rock sample became oil-wet, which was consistent with the wettability results measured by contact Angle. Therefore, the wettability of rock samples can be evaluated by 1D NMR technique combined with vacuum imbibition method, or by analyzing the changes of NMR spectra of aqueous phase in completely saturated water and saturated oil-bound water.

A new and simple method for patellar height measurement: Fibula-condyle-patella angle.

This study aims to evaluate the inter-observer reliability of fibula-condyle-patella angle measurements and to compare it with other measurement techniques. Between January 01, 2023 and January 31, 2023, a total of 108 patients (20 males, 88 females; mean age: 47.5±12.0 years; range, 18 to 72 years) who underwent X-rays using the fibula-condyle-patella angle, Insall-Salvati, Caton-Deschamps, Blackburne-Pell, and plateau-patella angle (PPA) methods were retrospectively analyzed. Knee lateral radiographs taken in at least 30 degrees of flexion and appropriate rotation were scanned. All measurements were made by two orthopedic surgeons who were blinded to measurement methods. Right knee patellar height measurements were conducted in 56 patients, while left knee patellar heights were assessed in 52 patients. The highest inter-observer concordance was found in the fibula-condyle-patella angle. The second highest concordance was found in the Insall-Salvati. The highest concordance correlation was found with PPA in the measurements of both researchers. The fibula-condyle-patella angle is a reliable technique with a good inter-observer reliability for measuring patellar height. We believe that this study will inspire future research to establish comprehensive reference values for clinical applications.

Comparison of “Van Herick’s” method versus “Borrone’s” method for estimating narrow angles

Background: Strategies for indirectly assessing the iridocorneal angle aim to be reproducible, reliable, and comparable to gonioscopy for screening in cases of narrow angles and their clinical spectrum. Objectives: The objective of this study is to determine which of the indirect estimation methods of the iridocorneal angle, either the "Van Herick" method or the "Borrone" method, exhibits a higher correlation with gonioscopy in detecting narrow iridocorneal angles in patients at the Ophthalmology outpatient clinic of the Hospital San Borja Arriarán. Materials and methods: A cross-sectional study was conducted with a sample of 32 patients (64 eyes) who met the inclusion and exclusion criteria. Results were obtained through gonioscopy, identifying narrow angles in 16 eyes and open angles in 48 eyes. Sensitivity and specificity of both methods (Borrone and Van Herick) were calculated in comparison to gonioscopy, using a selected cutoff point. Results: The Borrone method showed a sensitivity of 96% and a specificity of 91%, with a 95% confidence interval, compared to gonioscopy. In contrast, the Van Herick method demonstrated a sensitivity of 77% and a specificity of 82% in relation to gonioscopy. Discussion: The high sensitivity and specificity of the “Borrone” method are attributed to its technical details and its dichotomous nature, making it easier for the operator to determine and interpret. This reduces variability and provides a high correlation with gonioscopy. Conclusions: In this study, the “Borrone” method was found to have a more significant correlation with gonioscopy compared to the “Van Herick” method. Therefore, the “Borrone” method is considered more reliable and reproducible for detecting possible narrow iridocorneal angles, especially in high patient volume settings, such as ophthalmology outpatient clinics.

Damage creep model and application for sandy mudstone considering the effect of immersion deterioration

Abstract Aiming at the problem of performance degradation and large deformation of sandy mudstone after immersion in water, the compression test is carried out. The damage and deterioration law of strength and elastic modulus of immersed rock mass is analyzed, and the function relationship between rock damage variable and soaking time is obtained by fitting. Combined with the Hoek-Brown criterion and Mohr-Coulomb criterion, the calculation method of instantaneous cohesion and instantaneous internal friction angle of damaged rock mass is derived based on the tangent method, and the equivalent Mohr-Coulomb criterion which can effectively characterize the nonlinear strength characteristics of damaged rock mass is given. Based on the built-in creep model Cvisc of Flac3D, a damage creep model is given by introducing the damage factor and nonlinear strength criterion of immersed rock mass, which is more suitable for describing the creep characteristics of immersed sandy mudstone. The validity of the model is verified by comparing with the measured results.

Polarization angle information enhancement method based on polarimetric array imaging.

Polarization imaging, based on the measurement of polarization parameters containing specific physical information, has found extensive applications across various domains. Among these parameters, polarization angle information plays a crucial role in revealing texture details. However, in practical scenarios, noise during image acquisition can lead to significant degradation of polarization angle information. To address this issue, we introduce a novel, to the best of our knowledge, polarization angle information enhancement method based on polarimetric array imaging. Our proposed method utilizes the principles of polarimetric array imaging to effectively restore texture information embedded within polarization angle images. Through the deployment of a self-designed polarimetric array imaging system, we conducted experiments in diverse scenes to validate the efficacy of our approach. The acquired polarization angle data were subjected to our method for enhancement. The experimental outcomes distinctly illustrate the noise suppression capabilities of our method, showcasing its ability to faithfully reconstruct intricate details obscured by substantial noise interference.

Evaluation of rock and fluid intermolecular interaction between asphaltene and sand minerals using electrochemical, analytical spectroscopy and microscopy techniques

Long-time contact of heavy crude oil with rock leads to an adsorption phenomenon, which causes the rock surface to become oil-wet and appears as a barrier to the fluid flow in the porous media. However precise understanding of how asphaltene fractions influence sand wettability is lacking. The wetness of neat and asphaltene-aged sandstone was calculated using two relative permeability and contact angle methods. Then the molecular interaction between asphaltene and sand minerals was systematically analyzed using Fourier-transform infrared spectroscopy. Furthermore, the zeta potential was representative of electrostatic properties and surface charge alteration of the sand after these phenomena. Scanning electron microscopy with energy-dispersive X-ray (EDX) analysis also showed elemental mapping and dispersion of asphaltene particles on the rock surface. According to contact angle and EDX analyses of asphaltene samples, the contact angle rises from 115° to 141° by an increase in carbon adsorption on the sand surface from 8.23 to 41.56%. Spectroscopy results demonstrated that hydrogen-bonding, π-bonding, and sulfur-containing compounds such as sulfoxide improve asphaltene adsorption onto the sand surface. The higher the aromaticity index and hydrogen potential index of asphaltene, the greater the ability of asphaltene to change wettability. Adsorption of surface active components would make the surface charge of the sand more negative. The presence of nitrogen/sulfur-containing functional groups on the sand surface changed the electrostatic properties, as a sand surface coated with asphaltene would reduce the percentage of metal cations.