Straight Line Research Articles

Minimum zone fitting and error evaluation for arc correction type convex contour of bearing roller

The minimum zone fitting and error evaluation for the arc-modified convex contour of a bearing roller have important applications for consistency detection and quantificational research of the elastohydrodynamic lubrication of a bearing roller. Based on the definition of the shape error and the geometric characteristics of the arc corrected roller convexity line of the bearing, a new fitting and error evaluation method for the total convexity contour of a bearing roller is presented. First, the reference cutoff points of the arc segment and straight line are determined based on the curvature difference of each measurement point. Then, the measuring points on both sides of the two reference cutoff points are selected as auxiliary cutoff points for arc fitting. The fitting error is obtained based on the minimum area method. Finally, a series of tangent equations are obtained based on the tangent principle between a line and two arcs, and the straightness error is determined by calculating the distances between the measuring points and the tangents. The example results show that an arc-modified convex contour can be fitted, and its global error can be evaluated effectively and precisely using the presented method. This study also provides a new idea for the minimum zone fitting of multi-segment curves along a plane.

Data transformation and model selection in bivariate allometry.

Students of biological allometry have used the logarithmic transformation for over a century to linearize bivariate distributions that are curvilinear on the arithmetic scale. When the distribution is linear, the equation for a straight line fitted to the distribution can be back-transformed to form a two-parameter power function for describing the original observations. However, many of the data in contemporary studies of allometry fail to meet the requirement for log-linearity, thereby precluding the use of the aforementioned protocol. Even when data are linear in logarithmic form, the two-parameter power equation estimated by back-transformation may yield a misleading or erroneous perception of pattern in the original distribution. A better approach to bivariate allometry would be to forego transformation altogether and to fit multiple models to untransformed observations by nonlinear regression, thereby creating a pool of candidate models with different functional form and different assumptions regarding random error. The best model in the pool of candidate models could then be identified by a selection procedure based on maximum likelihood. Two examples are presented to illustrate the power and versatility of newer methods for studying allometric variation. It always is better to examine the original data when it is possible to do so.

Using Hough transform to define track boundaries as part of machine vision by train traffic-tracking hardware and software systems

Aim. In the context of machine vision, the problem of detected object boundary definition is usually solved using semantic segmentation that requires a high computational resource. Its application increases the complexity and the cost of the implemented hardware and software systems. This paper proposes an alternative method for defining the boundary of a segmented object, i.e., a railway track, for a train traffic tracking system. Methods. Since a railway track in an image can be represented by an n-th order polynomial, it is suggested to solve the problem of track boundary detection by using approximations in the form of straight lines. It is suggested using the Hough transform to detect straight lines. The former’s parametric space will be arranged in accordance with the problem to be solved. Conclusions. The proposed approximation will allow abandoning semantic segmentation and reduce the computational complexity and load.

A - 126 Examining Five Point Test Strategy Use on Everyday Problem-Solving Abilities in Mild Cognitive Impairment and Alzheimer’s Disease

Abstract Objective Activities of daily living (ADLs) and executive functional abilities are increasingly impaired in mild cognitive impairment (MCI) and Alzheimer’s disease (ad). Impaired individuals adopt executive strategies to aid in executing executive everyday tasks. The Five Point Test measures indices of executive functioning when completing the task. The study examines the role of strategy use in everyday problem-solving in healthy older adults (HOA), MCI, and ad. Method Participants included HOA adults (n = 58), persons with MCI (n = 63), and individuals with ad (n = 18). Participants completed a background questionnaire, including the Everyday Problems Test (EPT). In the Five Point Test, using straight lines, participants were instructed to draw various designs in three minutes, avoiding errors across three conditions. The use of the Rotational Strategy is measured by participants generating a new design by rotating the previous spatial configuration. The use of an enumerative strategy was measured by participants generating a pattern by consecutively adding or deleting a line from the previous design. Results Linear regressions were conducted to determine the role of strategy use in everyday problem-solving (i.e., rotational and enumerative strategies). It was revealed that the use of the rotational strategy predicted EPT solving in the MCI group. However, problem-solving abilities did not predict EPT solving in HOA and ad. Conclusion Interestingly, the rotational strategy was better executed across all groups, while the ad group exhibited limited strategy use. Results suggest that those with subtle cognitive deficits adopt strategies to better execute problem-solving in real-life problems.

Assessing the current role of AP and Bernageau view radiographs in measurement of glenoid bone loss in patients with recurrent shoulder dislocation: correlation with computed tomography, magnetic resonance imaging, and arthroscopy.

Evaluation of glenoid bone loss following recurrent anterior shoulder dislocations is normally performed using cross sectional imaging. To assess how anteroposterior (AP) and Bernageau view radiographs compare to computed tomography (CT), magnetic resonance imaging (MRI) and arthroscopy for evaluating glenoid bone loss in patients with recurrent anterior shoulder dislocation. A prospective observational study was performed on 32 patients over two years at a tertiary orthopedic center. The loss of sclerotic glenoid rim (LSGL) on AP radiograph and the percentage relative glenoid bone loss on the Bernageau radiograph were assessed. The percentage glenoid bone loss and anterior straight line (ASL) were calculated using a best fit en face circle method using CT and MRI. Percentage glenoid bone loss was also calculated during arthroscopy in multiples of 5%. In our study, 90.6% (29) patients were males, while only 9.4% (3) were females. This can be attributed to the involvement of the males in outdoor activities and sports. Also, the maximum number of patients were found to belong to 21-30years of age, with the mean age being 28.66years. Of the 32 patients, loss of sclerotic glenoid line (LSGL) on AP radiographs correlated with glenoid bone loss on cross-sectional imaging in 27 patients. Three patients had equivocal LSGL and 2 patients with glenoid bone loss on CT did not demonstrate LSGL. The difference between the two modalities was not statistically significant (p value = 0.002). The glenoid bone loss on Bernageau view correlated with glenoid bone loss on cross sectional imaging in all but one patient. The bone loss as evaluated by radiograph Bernageau view was found to have strong correlation (correlation coefficient r = 0.948, p value < 0.0001). AP and Bernageau radiographic views for anterior shoulder dislocations demonstrate good correlation with glenoid bone loss on cross-sectional imaging. They may also be used as an adjunct to predict overall bone loss on CT and at arthroscopy.

Partially invariant solution with an arbitrary surface of blow-up for the gas dynamics equations admitting pressure translation

We applied a method of symmetry reduction to the gas dynamics equations with a special form of the equation of state. This equation of state is a pressure represented as the sum of a density and an entropy functions. The symmetry Lie algebra of the system is 12–dimensional. One, two and three–dimensional subalgebras were considered. In this article, four–dimensional subalgebras are considered for the first time. Specifically, invariants are calculated for 50 four–dimensional subalgebras. Using invariants of one of the subalgebras, a symmetry reduction of the original system is calculated. The reduced system is a partially invariant submodel because one gas-dynamic function cannot be expressed in terms of the invariants. The submodel leads to two families of exact solutions, one of which describes the isochoric motion of the media, and the other solution specifies an arbitrary blow-up surface. For the first family of solutions, the particle trajectories are parabolas or rays; for the second family of solutions, the particles move along cubic parabolas or straight lines. From each point of the blow-up surface, particles fly out at different speeds and end up on a straight line at any other fixed moment in time. A description of the motion of particles for each family of solutions is given.

A new method for evaluating radial neck fractures based on Judet classification.

To propose a new method for evaluating paediatric radial neck fractures and improve the accuracy of fracture angulation measurement, particularly in younger children, and thereby facilitate planning treatment in this population. Clinical data of 117 children with radial neck fractures in our hospital from August 2014 to March 2023 were collected. A total of 50 children (26 males, 24 females, mean age 7.6 years (2 to 13)) met the inclusion criteria and were analyzed. Cases were excluded for the following reasons: Judet grade I and Judet grade IVb (> 85° angulation) classification; poor radiograph image quality; incomplete clinical information; sagittal plane angulation; severe displacement of the ulna fracture; and Monteggia fractures. For each patient, standard elbow anteroposterior (AP) view radiographs and corresponding CT images were acquired. On radiographs, Angle P (complementary to the angle between the long axis of the radial head and the line perpendicular to the physis), Angle S (complementary to the angle between the long axis of the radial head and the midline through the proximal radial shaft), and Angle U (between the long axis of the radial head and the straight line from the distal tip of the capitellum to the coronoid process) were identified as candidates approximating the true coronal plane angulation of radial neck fractures. On the coronal plane of the CT scan, the angulation of radial neck fractures (CTa) was measured and served as the reference standard for measurement. Inter- and intraobserver reliabilities were assessed by Kappa statistics and intraclass correlation coefficient (ICC). Angle U showed the strongest correlation with CTa (p < 0.001). In the analysis of inter- and intraobserver reliability, Kappa values were significantly higher for Angles S and U compared with Angle P. ICC values were excellent among the three groups. Angle U on AP view was the best substitute for CTa when evaluating radial neck fractures in children. Further studies are required to validate this method.

Evaluation of recent tectonic movement in northeast Japan by using long-term GNSS and tide gauge measurements

The study investigates tectonic movements in northeast Japan by using long-term (2000–2022) global navigation satellite system (GNSS) and tide gauge measurements. The effect of the 2011 Tohoku-Oki earthquake including the other eight seismic events that occurred within this period is also discussed using GNSS time-series. The result showed the break in GNSS-time series because of occurred earthquakes and pointed out tectonic movements significantly. The GNSS sites located in the central and southern parts of northeast Japan showed that the velocity vectors have strong internal variation and suggest the existence source of alternative deformation because of geological terranes within the region. A least square approach was used, and the trend of sea-level measurements was fitted with the straight line. The obtained results from tide gauge measurements showed a rising trend at almost every site and indicated lithospheric uprising movement because of tectonic activities. This is possible because of the ongoing subduction of the Pacific and Philippine Sea plates beneath the Eurasian and North American plates.

The efficacy and functional consequences of interactions between human spermatozoa and seminal fluid extracellular vesicles.

Seminal fluid extracellular vesicles (SFEVs) have previously been shown to interact with spermatozoa and influence their fertilisation capacity. Here, we sought to extend these studies by exploring the functional consequences of SFEV interactions with human spermatozoa. SFEVs were isolated from seminal fluid of normozoospermic donors prior to assessing the kinetics of sperm-SFEV binding in vitro, as well as the effects of these interactions on sperm capacitation, acrosomal exocytosis and motility profile. Biotin-labelled SFEV proteins were transferred primarily to the flagellum of spermatozoa within minutes of co-incubation, although additional foci of SFEV biotinylated proteins also labelled the mid-piece and head domain. Functional analyses of high-quality spermatozoa collected following liquification revealed that SFEVs did not influence sperm motility during incubation at pH 5, yet SFEVs induced subtle increases in total and progressive motility in sperm incubated with SFEVs at pH 7. Additional investigation of sperm motility kinematic parameters revealed that SFEVs significantly decreased beat cross frequency and increased distance straight line, linearity, straightness, straight line velocity, and wobble. SFEVs did not influence sperm capacitation status, or the ability of sperm to undergo acrosomal exocytosis. Functional assessment of both high- and low-quality spermatozoa collected prior to liquification showed limited SFEV influence, with these vesicles inducing only subtle decreases in beat cross frequency in spermatozoa of both groups. These findings raise the prospect that, aside from subtle effects on sperm motility, the encapsulated SFEV cargo may be destined for physiological targets other than the male germline, notably the female reproductive tract.

Kinematic Analysis of the Final Release position of elite Archer

The purpose of the study was kinematical analysis of an Elite archers. In present study total sample five Indian International level male Recurve category Archers was selected by Purposive sampling technique from SAI Archery training Center Sonipat. The age of the subjects was between 24 (± 5) years, hight of the subjects 6.0` (± 5 Inch), participation year between 2016-2022, shooting FITA score between 650-720 in archery was selected as a subjects for the study. According to Casio EX-F1 high speed camera was used, which have frequency from 60-300 frames per second (f/s). The data were recorded from Superior view, Lateral view, Anterior view and Medial view. The distance between shooting line and target is 70 meter. Shooting line is passed horizontally through the Center of Gravity box, Center of Gravity box is a square box drown with the measurement of 1×1 m, Center of Gravity box is equally divided into 4 parts. A straight line is passed vertically on it and a horizontal line which is shooting line and is drawn 70 meter apart from the target. The distance between bull eye of the target and the floor surface is 5 feet. Siliconcoach Pro8 update motion analysis software and Tracker motion analysis software was used for kinematical analysis of at the time of final release position in archery. Descriptive statistic was used. To find out multi correlation between dependent variable performance on target 1-10 (bull eye) in points and independent variables (selected linear variables). The significant correlation was found between Height of body Center of Mass, Height of body Center of Gravity, Height of Projectile and obtained value (-.893), (.878), (-.945) is greater than tabulated value of (.878) therefore it shows significant relationship of this independent variable with performance in archery. Whereas, in case of Body force aliment right medial, Body force aliment left medial the obtained values (.360) and (.770) are lower than tabulated value of (.878) therefore it shows insignificant relationship of these independent variable with performance in archery. The significant correlations with height variables suggest that certain aspects of an archer's body positioning, such as the height of the center of mass, center of gravity, and projectile, play a crucial role in archery performance. The negative correlation with the height of the center of mass implies that a lower center of mass is associated with better performance. The insignificant correlations with body forced alignment variables suggest that, at least within the parameters measured, the lateral alignment of the body (right and left medial) does not significantly influence performance in archery. Since the significant relationship was found between Height of body Center of Mass and Height of body Center of Gravity, Height of Projectile and Body force aliment left medial of the subject among independent variables as calculated “r” (-.960), (.887), (-.959) is found greater than the required tabulated value of (.878) at .05 level of significance. In case be seen the significant relationship was found between Height of body Center of Gravity and Body force aliment left medial of the subject among independent variables as calculated “r” (.935), is found greater than the required tabulated value of (.878) at .05 level of significance. The strong correlations among these variables indicate a close relationship between the height-related kinematic variables (center of mass, center of gravity, and projectile) and the lateral alignment of the body (body forced alignment left medial). The negative correlations suggest that as the height of the center of mass decreases, the height of the center of gravity and the height of the projectile tend to decrease, and as the height of the projectile decreases, the body forced alignment left medial tends to increase. The study concludes that there is a statistically significant and positive relationship between the height of the center of gravity and body forced alignment on the left medial side in archery. This finding implies that variations in the height of the center of gravity are associated with corresponding changes in the lateral alignment of the body, specifically towards the left medial side.

Theoretical study on the movements of bubbles

The radial and translational motions of multiple interacting spherical bubbles are obtained using classical Newton mechanics. It is seen that bubbles not only move in straight line, but also in circular motion. The tracks of the bubbles show that the interactions among them include attractive, repulsive and dynamic equilibrium. There are three types of straight line corresponding to attraction, coexistence of attraction and repulsion and dynamic equilibrium, and two types of circular movement corresponding to attraction and dynamic equilibrium. The results can provide an explanation for cavitation chain and profile in cavitation field.

Creep Fatigue Interaction at high temperature in C630R ferritic/martensitic heat-resistant steel

The study investigated the creep-fatigue interaction behavior, fracture mechanism, and microstructure evolution of C630R ferritic/martensitic heat-resistant steel at 630 °C and 1% strain amplitude. The results indicate that C630R ferritic/martensitic heat-resistant steel exhibits noticeable cyclic softening behavior, with a decrease in the softening ratio from 0.46 to 0.40 as loading time increases. Microstructure evolution was examined using optical and scanning electron microscopes, revealing the appearance of secondary cracks on the longitudinal section of the sample. These cracks exhibited a curved expansion trend with multiple deformations and highly bifurcated micro-cracks at a low loading time of 30s. However, when the load holding time was increased to 300s, the fatigue cracks tended to expand in a straight line with fewer branches. Furthermore, the observed crack growth path under different loading times showed enrichment in Fe and Cr, with the crack tip containing Cr oxide, which helped prevent fatigue crack propagation. As the loading time increases, the rise in crack closure resulting from oxidation leads to a decrease in crack propagation. Electron backscatter diffraction observation revealed the formation of numerous substructures and recrystallized grains after varying holding times, enhancing the material's resistance to crack propagation. Moreover, the study found that with increasing load dwell time, the deformed grains decreased, and substructural grains became dominant (57.68% and 62.77% under 30s and 300s, respectively). This increased crack resistance resulted in shorter secondary cracks under prolonged load retention, with the secondary crack length decreasing from 146.36μm at 30s loading time to 109.09μm at 300s loading time. Additionally, the kernel misorientation angle value decreased significantly after different loading times, leading to a higher likelihood of cracks or holes forming in regions with high KAM values, where low-angle grain boundaries were formed.

CosineTR: A dual-branch transformer-based network for semantic line detection

Semantic line is a straight line based representation designed to well capture the spatial layout or structural shape of the scene in an image that is valuable as a high-level visual property. In this paper, we propose an efficient end-to-end trainable semantic line detection model named Complementary semantic line TRansformer (CosineTR), which is designed according to an old proverb “two heads are better than one”. CosineTR adopts a dual-branch framework to detect semantic lines with a coarse to fine strategy. These two branches are built based on well-designed attention modules to capture multi-scale line semantic features locally and globally, and are equipped with heatmap prediction head and parameter regression head respectively to perform semantic line detection from two different perspectives. In addition, we introduce bilateral region attention and Gaussian prior cross-attention modules to reinforce semantic contexts extracted by the two branches, and couple them to form complementary feature representations by leveraging a feature interaction method. Extensive experiments demonstrate that our approach is effective and achieves competitive semantic line detection performance on multiple datasets.

PELATIHAN PENGGUNAAN APLIKASI GEOGEBRA PADA MATERI PERSAMAAN GARIS LURUS

The background for this community service activity is Pakis Islamic Middle School, which is one of the schools that has not yet implemented too many ICT-based learning models. This is due to the lack of projector facilities provided in each class as a medium for implementing ICT-based learning models. One learning model that is suitable to be applied based on the material being studied is to use the Geogebra application. Students can see the interpretation of graphs through the application. This service activity is carried out using the training method for trainees who are studying straight line equations. During the activity, monitoring was also carried out by the service team and evaluation through the results of test scores and questionnaires. The result of this community service activity is that the test results of the trainees found an average of 83.2. From this average, the training can be said to be successful because it is above the KKM standard in mathematics. While the value of the questionnaire was found that 92% of the training participants gave a positive response to using the Geogebra application on straight line equations. The advantages that trainees find are graphs that can be generated quickly, the GeoGebra application can provide a clearer visual experience to trainees in understanding mathematical concepts, can be used as an evaluation to ensure that the graphs that have been made are correct.

Weak-inertial effects on destabilized receding contact lines

It is known that, beyond a critical speed, the straight contact line of a partially -wetting liquid destabilizes into a corner. One of the earliest theoretical works exploring this phenomenon [Limat and Stone, ] elicited a self-similar conical structure of the interface in the viscous regime. However, noting that inertia is not expected to be negligible at contact line speeds close to and beyond the critical value for many common liquids, we provide the leading-order inertial correction to their solution. In particular, we find the self-similar corrections to the interface shape as well as the flow field, and also determine their scaling with the capillary number. We find that inertia invariably modifies the interface into a cusplike shape with an increased film thickness. Furthermore, when incorporating contact line dynamics into the model, resulting in a narrowing of the corner as the contact line speed increases, we still observe an overall increase in the inertial contribution with speed despite the increased confinement. Published by the American Physical Society 2024

Measurement of the water vapor transmission rate at temperatures above 100 °C

ABSTRACT Water vapor transmission rate (WVTR) and water vapor permeability coefficient were measured at temperatures between 110 and 138°C using the modified cup method. The cup, placed in a Highly Accelerated Stress Test chamber, allowed water vapor to permeate the sample film attached to the cup. The WVTR was determined based on the increase in mass of the cup. To prevent sample damage during measurement, a cup with a pressure adjustment mechanism was utilized. Carrier-incorporated phosphorus pentoxide was used as the desiccant instead of anhydrous calcium chloride to ensure a consistent moisture absorption rate, especially at high temperatures. The water vapor permeability coefficients for the polycarbonate, polyimide, and adhesive films were distributed on an approximately straight line in the Arrhenius plot. Additionally, the Arrhenius plots for the polyethylene terephthalate and polyethylene naphthalate films captured the permeability bending point near the glass transition temperature. To accurately measure the high-temperatureWVTR, upper and lower limits were established for the weighing interval, cup mass gain, and WVTR measurement range.

Comparing spatial differences in behavioral pattern transition of Black-tailed gull during post breeding season in the Korean peninsula

Parents adjust their foraging effort according to the chick and their own body condition and dual foraging strategy is one of the foraging tactics parents replenish their own reserves while feeding their chicks. During the post-breeding season, seabirds disperse to recover their own body condition and prepare for the next breeding season. Recently, we discovered Black-tailed gulls (Larus crassirostris) breeding around the Korean Peninsula occasionally foraging long trips during the late fledging, however, our understanding of the behavioral patterns of Black-tailed gulls during the late fledging and post-breeding, as well as its inter-colonial differences, remains considerably limited. Here, we employed 92 GPS trackers to adult Black-tailed gulls (Larus crassirostris) from six breeding colonies around the Korean peninsula (Yellow Sea—three colonies, South Sea—one colony, and East Sea—two colonies). To determine the foraging investment during the fledging, we suggested the flight efficiency in each trip as the ratio of maximum foraging distance (i.e., straight line distance) to total foraging distance (i.e., sum of all consecutive distance for each trip). Overall, the mean flight efficiency of the long foraging trips were lower than 57% (40.76 ± 13.07%) whereas that of the short foraging trips were over 74% (80.87 ± 4.03%). This may suggest that Black-tailed gulls may visited more than one foraging site during the long foraging trip while they flew directly between the foraging site and breeding colony during the short foraging trip to invest more in their juvenile. Moreover, longer maximum foraging distance with higher flight efficiency observed in the East Sea may indicate a balance between the costs (such as energy expended during foraging or food competition near breeding sites) and the benefits (quantity and quality of food obtained). Our findings revealed the flight behavior of Black-tailed gulls during the late fledging and post breeding, across six breeding colonies, which have different competition pressures and proximity to foraging site.

Unsteady CFD simulation of a rotor blade under various wind conditions

Wind and gusts can significantly impact the performance of rotors and turbines. The transient behavior of the rotor should be carefully examined to account for these effects. This paper investigates the unsteady aerodynamic characteristics of a rotor blade under different wind conditions, such as direction, speed, and angle. A 3D transient Computational Fluid Dynamics (CFD) simulation using the dynamic mesh technique is performed to analyze the rotor dynamics. The unsteady Reynolds-averaged Navier–Stokes (URANS) equations with the k-ω SST turbulence model are solved. The rotor blade used for this study is the U15XXL Combo KV29 industrial blade, which has not been numerically analyzed before. The results show that wind in the same direction as the rotation reduces the thrust more than lateral or opposite wind. Lateral wind with a speed lower than 5 m/s decreases the blade performance, but higher speeds increase it. Higher lateral wind speeds also cause two peaks in the torque curve, forming a butterfly wing shape in the polar torque plot and multiple extrema in the torque curve with increasing speed. The maximum thrust shifts slightly to the left with increasing lateral wind speed. The lateral angle does not affect the average thrust produced in one blade revolution but only causes a spatial shift. The thrust production decreases as the angle approaches the opposite direction of rotation. The motion amplitude decreases, and the curve becomes smoother as this angle increases. A nearly straight line similar to no side wind is observed at 60 and 90 degrees, which is attributed to the constant effective angle of attack during the rotation cycle.

Molecular Properties of Monoaminergic Catecholamines in Water.

Three neurotransmitters belonging to catecholamines (dopamine, noradrenaline, adrenaline) and related α-amino acids (DOPA and tyrosine) were studied by quantum-chemical ab initio and DFT calculations using B3LYP and DLPNO-CCSD(T) methods in water. In addition to the three canonical forms, zwitterionic forms were also investigated, each in three oxidation states (molecular cation L+, electroneutral molecule L0, and molecular anion L-). Each species was subjected to geometry optimization followed by vibrational analysis. Electronic properties (adiabatic ionization energy, electron affinity, chemical hardness, molecular electronegativity, electrophilicity index, dipole moment, electric polarizability, and quadrupole moment) and standard thermodynamic quantities (inner energy, entropy, enthalpy, and Gibbs energy) were evaluated, which allows the absolute oxidation and reduction potentials to be calculated. The absolute reduction potential (ARP) was found to correlate with the electrophilicity index ω along a straight line. Moreover, in addition to the standard expression for the absolute redox potential using reaction Gibbs energy, an approximation based on ionization energy and/or electron affinity was also tested. The main finding is that dopamine is a much weaker oxidizing agent with the ARP = 0.99 V relative to tyrosine with ARP = 1.38 V for canonical structures in water. This is also true for the zwitterionic structures in water: for dopamine ARP = 0.63 V is much lower relative to tyrosine with ARP = 1.31 V. The protonated form (DOPAH+) has the highest ARP = 2.02 V. Prediction of the redox potentials is an important factor influencing antioxidant (EC50) and/or antireductant activity. Based on 16 molecular properties for 20 molecules (320 entries), advanced statistical methods (cluster analysis, principal component analysis, pair-correlation) reveal that several groups of similarity exist: {dopamine-noradrenaline}, different from {adrenaline-DOPA-(tyrosine)} and zwitterionic forms of {dopamine-noradrenaline-adrenaline}.

SIMPLIFIED COMPUTATIONAL TOOL FOR PREDICTING FORMATION DAMAGE IN OIL WELLS

The present study underscores the significance of regular well test analysis to ensure the accuracy and consistency of data pertaining to the permeability and skin of exploratory wells. This study advances the development of a novel computer model, ASPIRE, which predicts formation damage in oil wells by analysing well-test data. In this context, identifying blocked pore throats in the formation close to the wellbore by paraffinic deposits (scales) and its influence on permeability necessitates routine well-test analysis. The software employs a modified linear regression model developed in this study to perfectly fit the well-test data's infinitely acting linear flow (IARF) region to a straight line. The cases "CASE 1" and "CASE 2" were considered for constant rate transient drawdown well test analyses. The findings indicate that Case 1, with a high skin factor, requires remedial action, such as stimulation, to increase the formation's permeability close to the wellbore for enhanced productivity. In contrast, Case 2 has higher permeability and lower skin factor than Case 1, so stimulation is not required. In addition, R-squared analyses were conducted to validate the results obtained from the developed tool. The analyses reveal an R-square value of 1 for all cases, indicating a 100% accuracy. Therefore, the study concludes that the developed tool is instrumental in accurately predicting formation damage in oil wells.