Approximation Of Curves Research Articles

3-Dimensional Quartic Bézier Curve Approximation Model by Using Neutrosophic Approach


 In a 3-dimensional data collection process, there exists noise data that cannot be included to visualize the process. Therefore, it is difficult to deal with since fuzzy set and intuitionistic fuzzy set theories did not consider the indeterminacy problem. However, using a neutrosophic approach with three memberships: truth, false, and indeterminacy membership function, the error data will be treated as uncertain data by using the indeterminacy degree. Thus, this study will visualize the 3-dimensional quartic Bézier curve model by using neutrosophic set theory. To construct the model, the neutrosophic quartic control point must first be introduced to approximate the neutrosophic quartic Bézier curve. Next, the Bernstein basis function as the methodology of this study will be blended with the neutrosophic fundamental notion. At the end of this paper, a numerical example of the 3-dimensional neutrosophic quartic Bézier curve will be visualized by using the approximation method as the finding of this study. Finally, this study provides significant contributions to making it easier for data collectors to visualize all data, which means that no data will be eliminated since the uncertainty data will also be used.

Approximation of holomorphic Legendrian curves with jet-interpolation

We prove several interpolation results for holomorphic Legendrian curves lying in an odd dimensional complex Euclidean space with the standard contact structure. In particular, we show that an arbitrary countable set of points in C2n+1 lies on an injectively immersed isotropic surface with a prescribed complex structure. If the set has no accumulation points, the surface may be taken properly embedded. We also prove a Carleman-type theorem for holomorphic Legendrian curves with interpolation. Namely, a Legendrian curve, defined on a certain type of unbounded closed set in a given open Riemann surface R, may be approximated in the C0-topology by an entire Legendrian curve with prescribed finite-order Taylor polynomials at a closed discrete set of points in R. Under suitable conditions, the approximating map may be made into a proper embedding.

Spline-slip model for friction hysteresis identification

The paper concerns the study of the quadratic b-spline curve application for the regime of pre-sliding displacements in the GMS friction hysteresis model approximation. The impact of the modification on the effectiveness of modelling the friction properties and computational efficiency is analysed. The curve approximation technique with smooth quadratic b-spline, instead of piecewise linear curve generated by Maxwell elements, transforms the multi-state GMS model into a single-state model (the spline-slip model). The solution makes the precision of friction modelling in the spline-slip model independent on the number of parameters, thus eliminating the main problem of the GMS model. The simulations show that the new model incorporates all the friction modelling capabilities provided in the GMS model.

Results of capillary studies digital processing and interpretation with the aim of a pore channel size distribution function constructing

Pore channels distribution in reservoir by size largely determines such filtration parameters as absolute and phase permeability, as well as the residual oil saturation of the productive reservoir. This paper presents a technique for capillary research data digital processing in order to obtain a function graph of reservoir pore channels by size distribution. In this case, a generalized mathematical model of capillary pressure curves is used. The generalized model makes it possible to increase the accuracy of capillary curves approximation in the medium and small pore channels area. In this regard, the proposed digital processing technique makes it possible to increase the accuracy and efficiency of constructing the pore channel size distribution function. Keywords: pore channels; distribution density; permeability; oil saturation; digital processing technique.

Dose-response associations of maternal age with pregnancy complications and multimorbidity among nulliparas and multiparas: A multicentric retrospective cohort study in southern China.

Advanced maternal age is becoming an increasingly common issue worldwide, presenting substantial health risks to pregnant women. However, dose-response associations of maternal age with a comprehensive range of pregnancy complications and their multimorbidity remain unclear. We conducted a retrospective cohort study using data from China's National Maternal Near Miss Surveillance System for 2017-2018, including 18 hospitals in southern China. We included 135 274 pregnant women aged 15-54 years with a singleton birth. We used multivariable logistic regression and restricted cubic spline to examine dose-response associations between maternal age and various pregnancy complications, as well as multimorbidity. We employed the Apriori algorithm to mine the association rules among pregnancy complications and identify frequent multimorbidity patterns. We found three distinct patterns of associations between maternal age and specific pregnancy complications. In relation to increasing maternal age, gestational diabetes mellitus, preeclampsia, and gestational hypertension showed nonlinear increasing trends for both nulliparas and multiparas, as did multimorbidity in nulliparas. Conversely, we observed linear increasing trends for placental previa in both nulliparas and multiparas, placental abruption in nulliparas, and multimorbidity in multiparas. Infection and severe anaemia had an approximate J-shaped curve among nulliparas, while postpartum haemorrhage exhibited a similar curve in both nulliparas and multiparas. Advanced maternal age was linked to an elevated risk of multimorbidity during pregnancy or postpartum period, exhibiting more complicated patterns. The most common multimorbidity patterns in this age group were "preeclampsia + gestational diabetes mellitus", "gestational hypertension + gestational diabetes mellitus", "infection + gestational diabetes mellitus", and "placental previa + gestational diabetes mellitus". Maternal age was associated with pregnancy complications and multimorbidity in three broad dose-response manners, including approximate J-shaped curves, as well as nonlinear and linear increasing trends, depending on the specific outcome and parity, which may suggest different underlying biological mechanisms. Women with advanced maternal age had a higher risk and more complicated patterns of multimorbidity during pregnancy or postpartum, suggesting that this group should be targeted for more intensive health care.

Measurement and Calculation Techniques of Complex Permeability Applied to Mn-Zn Ferrites Based on Iterative Approximation Curve Fitting and Modified Equivalent Inductor Model

In many cases, power inductors are responsible for most of the power loss, volume, and cost if applied to high-frequency power electronics applications. It is desirable to optimize their design by the proper calculation of winding and core loss. It allows faster and cheaper commercial product release, which is the key to being successful in a highly competitive market. This is only possible if existing calculation techniques and technical data given by, e.g., core manufacturers, are verified and correct; otherwise, the inductor optimization process is less precise and requires several iterations to achieve good convergence. This paper addresses existing and proposes improved measurement and calculation techniques with regard to complex permeability, one of the key quantities that define inductor behavior in the frequency domain. This is done through impedance measurement and improved definition of the equivalent inductor model. Moreover, the proposed calculation techniques fulfill the need for the simple, accurate analytical methods required in commercial designs.

Efficient active contours with optical physical parameters for shoreline extraction: a general method and novel framework

ABSTRACT Accurate shoreline extraction is important for global climate change, land-sea interactions, and ocean dynamics. However, many current shoreline extraction methods have limitations in accuracy and efficiency when applied to different data, resulting from either empirical model parameters or limited image types. Considering the advantages of active contour in applying variational ideas to solve energy generalizations and the universal adaptability of optical physical parameters, an active contours with optical physical parameters (ACOPP) method that rapidly converges for shoreline extraction is proposed in this study. This model uses active contours to calculate the pixel-level energy generalization function of the image and combines the energy of the optical physical parameters to accelerate the process of contour curve approximation to the target edge by energy confrontation through iterative fitting, and improve the accuracy and efficiency of the target curves. Different images with multiple time phases in different regions were selected as experimental data, including GF2, SPOT-5, Sentinel-2, and Landsat-8, to demonstrate the accuracy, efficiency, and universality, while shoreline complexity coefficient was proposed for the study area division, which was used for shoreline extraction by ACOPP. Finally, the extraction results were analysed and validated, and the conclusions are as follows: ACOPP has a faster convergence speed in the extraction process than traditional methods, and the extraction results have a higher spatial resolution. The extraction results were highly accurate, and the mean absolute error (MAE) compared with the validation sets was < 2 pixels. The model is applicable to remote sensing images in which the normalized difference water index (NDWI) can be calculated, that is, optical remote sensing images containing green and near-infrared (or mid-infrared) bands. The experimental results prove the feasibility of ACOPP and a novel framework that combines ACOPP to extract target feature edge information for remote sensing images is proposed, the feasible and extensible of the frame have been verified.

Understanding of the properties of neural network approaches for transient light curve approximations

Context. Modern-day time-domain photometric surveys collect a lot of observations of various astronomical objects and the coming era of large-scale surveys will provide even more information on their properties. Spectroscopic follow-ups are especially crucial for transients such as supernovae and most of these objects have not been subject to such studies. Aims. Flux time series are actively used as an affordable alternative for photometric classification and characterization, for instance, peak identifications and luminosity decline estimations. However, the collected time series are multidimensional and irregularly sampled, while also containing outliers and without any well-defined systematic uncertainties. This paper presents a search for the best-performing methods to approximate the observed light curves over time and wavelength for the purpose of generating time series with regular time steps in each passband. Methods. We examined several light curve approximation methods based on neural networks such as multilayer perceptrons, Bayesian neural networks, and normalizing flows to approximate observations of a single light curve. Test datasets include simulated PLAsTiCC and real Zwicky Transient Facility Bright Transient Survey light curves of transients. Results. The tests demonstrate that even just a few observations are enough to fit the networks and improve the quality of approximation, compared to state-of-the-art models. The methods described in this work have a low computational complexity and are significantly faster than Gaussian processes. Additionally, we analyzed the performance of the approximation techniques from the perspective of further peak identification and transients classification. The study results have been released in an open and user-friendly Fulu Python library available on GitHub for the scientific community.

Cost of illness for colorectal cancer in Japan - a time trend and future projections (1996–2035) based on governmental statistics

BackgroundIn Japan, the crude mortality rate of colorectal cancer is the second highest among men and highest among women by site. We aimed to calculate the social burden of colorectal cancer using the cost of illness (COI) method and identify the main factors that drove changes in the COI.MethodsFrom 1996 to 2020, the COI was estimated by summing direct, morbidity, and mortality costs. In addition, the COI by 2035 was projected by fitting approximate curves obtained from historical data to health-related indicators by sex and age. Future projections of the number of patients by the stage of disease were also made to explore the factors that changed the COI.ResultsThe number of deaths and incidence from colorectal cancer was expected to continue increasing due to population aging. However, the COI was projected to rise from 850.3 billion yen in 1996 to 1.451 trillion yen in 2020, and peaked at 1.478 trillion yen in 2023 before it declined.ConclusionAlthough the increased number of deaths associated with population aging increased COI, it was expected that the COI would decrease around 2023 due to a decrease in the human capital value of the deceased. In addition, the mortality rate was expected to decrease in the future due to an increase in the percentage of early detection of colorectal cancer via widespread screening and advances in medical technology.

Technology diffusion and uneven development

We propose a conceptualisation of the process of technology adoption that takes into account the uneven relative costs of technology implementation, especially country differences in wage levels. The novelties and contributions of our approach are the following. First, we introduce a dynamic macroeconomic model of technology diffusion, which is the first to directly account for the difference in factor cost proportions in an endogenous cross-country setting. Second, we utilise the Cross-country Historical Adoption of Technology (CHAT) and Penn World Table databases to calibrate the model using non-linear approximation across countries and technologies, which explains about 50% of the variability in technology density. Third, the results of the calibrated model offer a new insight into the dynamics and patterns of technology diffusion of differently developed countries, offering both an approximation of the average technology adoption across differently developed countries over time and an approximation of the relative technology density adoption curves, which are country specific generalisations of the logistic curves and depend highly on the general level of development and wage levels.

Internal organ dose rate conversion coefficients of Japanese macaques to 134Cs,137Cs and 131I†.

The purpose of this study was to estimate the internal dose of radiation in Japanese macaques (aka Nihonzaru or snow monkey) due to the Fukushima nuclear power plant accident. Images of a male Japanese macaque weighing ~10kg were acquired using a multi-slice computed tomography (CT) scan with a 64-row segment detector. The CT images were used to create voxel phantoms of the bones, bone marrow, brain, eyes, heart, lungs, stomach, liver, spleen, pancreas, kidneys, intestines, bladder, testes, thyroid and miscellaneous tissue. The Particle and Heavy Ion Transport System (PHITS) Monte Carlo code was used to calculate the internal exposure rate conversion factors for 134Cs, 137Cs and 131I isotopes for the created voxel phantoms with a statistical precision higher than 1%. The PHITS-calculated energy deposits were compared with those for rhesus monkeys. The results showed that the fractions of energy deposits for β-radiation in different organs were almost identical between the two species. For γ-radiation, there was excellent agreement in the self-absorption rate with the approximate curve of the Japanese macaque, with an average deviation of 2%. The maximum deviation of 12% was for the kidney, which has two organs, so the error with the approximate curve is slightly larger due to the energy loss created between organs.

Improving geometric iterative approximation methods using local approximations

In this study, we propose improvements to Geometric Iterative Methods (GIM) for curve and surface approximation. Our key contributions include introducing an error vector function and deriving new error vectors, which enhance the approximation quality compared to the Least Squared Progressive and Iterative Approximation (LSPIA) methods. Additionally, we integrate parameter correction and control points update based on local approximations, achieving comparable accuracy to Geometric Approximation (GA) methods while being more computationally efficient. Extensive experiments demonstrate the superior accuracy and computational efficiency of our method.

Globally certified [formula omitted] approximation of planar algebraic curves

Topology analysis and geometric feature determination for curves and surfaces are basic problems in geometric modeling and computer aided design. When the curves and surfaces are given in implicit expressions, the problems become more difficult. This paper presents a complete algorithm framework for the problem of certified G1 approximation of a planar algebraic curve under global error control. Compared to other work on topology and geometric analysis of algebraic curves, this method presents a new topology analysis as well as a geometric information computation. Moreover, this method uses generalized asymptotes as the approximation of the unbounded part, which makes it achieve global approximation with given precision.

IMM27M, a humanized Fc-engineered anti CTLA-4 antibody, in patients with advanced solid tumors: A phase I dose-escalation study.

e14670 Background: IMM27M is a humanized Fc-engineered IgG1 CTLA-4 monoclonal antibody with enhanced ADCC. In pre-clinical models, IMM27M could enhance immune responses and promote Treg depletion. The pre-clinical results showed IMM27M induced a significantly stronger anti-tumor activity than ipilimumab and resulted in complete tumor remission even at a low dose. Methods: This study is an open-label, multi-center, phase I dose-escalation study conducted to evaluate the safety, tolerability, maximum tolerated dose/recommended dose for expansion, PK and anti-tumor activity in patients with advanced solid tumors. The study was designed with an accelerated titration followed by a standard 3+3 design. IMM27M (0.1,0.3,1,2,3 mg/kg) was administered as monotherapy on Day 1 of every 3 weeks. Results: As of 30 Dec 2022, the dose has been escalated to 2mg/kg. 11 pts (8 female, 3 male) were enrolled and treated (1 at 0.1 mg/kg, 3 at 0.3 mg/kg, 3 at 1.0 mg/kg, 4 at 2.0 mg/kg), including 3 pts with melanoma, 3 pts with breast carcinoma, 2 pts with RCC, 1 pt with HCC, 1pt with NSCLC and 1 pt with ovarian carcinoma. Median age was 52 years (range 36-72). 9 pts (81.8%) received ≥ 2 lines of previous systemic therapies and 7 pts (63.6%) received previous anti PD-1/PD-L1 treatment. Treatment-related adverse events (TRAEs) occurred in 10 pts (90.9%) to date. Most TRAEs were grade 1 or 2. The most common TRAEs (≥ 10%) of all grades were anaemia (n = 3 [27.3%]), white blood cell count decreased (n = 2 [18.2%]), lymphocyte count decreased (n = 2 [18.2%]), constipation (n = 2 [18.2%]) and rash (n = 2 [18.2%]). Grade ≥3 TRAEs occurred in 2 pts (18.2%): lymphocyte count decreased (G3, n = 1 [9.1%]) and immune-related lung disease (G3, n = 1 [9.1%]). Treatment related SAE patients only occurred in 1 pt (immune-related lung disease, possibly related to treatment), and this patient recovered after clinical treatment. No DLT was observed. No TRAE leading to treatment discontinuation was reported. In 10 response evaluable pts, 3 pts had SD as best response. One pt in 2.0 mg/kg dose cohort had tumor shrinkage of 17% at Week 6, who had metastatic melanoma and received 2 lines of previous treatments including anti PD-1. The treatment of this patient is ongoing. Preliminary PK analysis of IMM27 showed an approximate proportional dose curve and the mean t1/2 was around 11 days. Conclusions: IMM27M monotherapy in general was well-tolerated at the dose level evaluated and preliminarily anti-tumor activity in patients with advanced solid tumors. The dose escalation study of IMM27M in advanced solid tumors is ongoing. Clinical trial information: NCT05235438 .

Study on the relationship between the design parameters of bridge wire electric initiating devices and the electrothermal response curve

The parameter settings of the transient thermal response test conditions of bridge wire electric initiating devices are studied. The effects of bridge wire resistance parameters and charge pressure on the electrothermal response curve were explored. The results show that when the state of the bridge wire and the surrounding agents are basically the same, the electrothermal response curve can clearly reflect the difference in the resistance of the bridge wire. The larger the bridge wire resistance, the more sensitive the bridge wire to the electrical pulse, and the charging pressure parameters also have a significant impact on the electrothermal response curve. The smaller the charging pressure, the more sensitive the product electrothermal response. When the density of the agent is basically the same, the approximate response curve and parameter calculation results can be obtained.

Wind power calculation based on sums of diffusion method and a novel power curve approximation model

The Ceylon Journal of Science is a peer-reviewed journal published quarterly by the University of Peradeniya, Sri Lanka in March, June, September and December. It is aimed at publishing high quality research articles on topics related to different disciplines in Science. The journal accepts original research articles, book reviews, reviews and mini-reviews, short communications, opinions, research notes, and commentaries and notes. The Journal has its own website https://site.pdn.ac.lk/cjs/. The journal strictly adheres to publication ethics as emphasized by the Committee on Publication Ethics (COPE). It is indexed in Sri Lanka Journals Online (SLJOL), Directory of Open Access Journals (DOAJ), Google Scholar and Zoological Records. According to the Google Scholar;H5-Index: 12H5-Median: 15According to the Exaly (1970 – 2021);Impact Factor: 0.6 (top 19%)Extended IF: 0.6 (top 19%)H-Index: 8 (top 28%)Citations/paper: 1.42

FEATURES OF THE CALCULATION OF ROLLS ON THE FATIGUE STRENGTH

On modern rolling mills, manufacturers have the possibility to use a wide range of materials with technologically determined properties, which allows for effective use of rolls and improvement of technical and economic indicators of production processes. Reasonable choice of materials and properties of rolls is impossible without reliable methods of calculating the strength and predicting the service life of the rolls. In particular, increasing of the reliability of methods for calculating the fatigue strength of rolls is an urgent task, both for scientists and for technologists and specialists of rolling mills.&#x0D; The purpose of the work is to study the features of fatigue calculation of rolls based on the predicted number of load cycles. The work solves the problem of assessing the possibility of applying a known method of determining the predicted number of load cycles and studying the features of such a method for rollsofrolling mills.&#x0D; The method of calculation based on the approximation of Woehler curves for the roll material by Beskin's power dependence within the zone of high cycle fatigue, which was determined by the number of cycles from 1·103 to 5·106, was considered. It has been proven that such a technique can be used for rolls into account the identified features. The main features of the calculation of rolls for fatigue strength include: a symmetrical cycle of changes in bending stresses and a pulsating cycle of changes in torsional stresses; mandatory consideration of working conditions due to the modified endurance limit of the material; compliance with the condition that the working stresses exceed the modified endurance limit, but are less than the admissible stresses for the roll material; taking into account the stress concentration depending on the shape of the grooves that form the passes. Consider influence the effect of stress concentration in the grooves of the rolls requires clarification based on empirical data of a certain rolling mill.&#x0D; The application of the fatigue calculation method for rolls, with considerthe identified features, will allow to increase the accuracy of determining the predicted terms of operation of the rolls and determining their consumption.

Predictability of Astigmatism Correction by Arcuate Incisions with a Femtosecond Laser Using the Gaussian Approximation Calculation.

Planning astigmatic correction is a complex task. Biomechanical simulation models are useful for predicting the effects of the physical procedure on the cornea. Algorithms based on these models allow preoperative planning and simulate the outcome of patient-specific treatment. The objective of this study was to develop a customised optimisation algorithm and determine the predictability of astigmatism correction by femtosecond laser arcuate incisions. In this study, biomechanical models and Gaussian approximation curve calculations were used for surgical planning. Thirty-four eyes with mild astigmatism were included, and corneal topographies were evaluated before and after femtosecond laser-assisted cataract surgery with arcuate incisions. The follow-up time was up to 6 weeks. Retrospective data showed a significant reduction in postoperative astigmatism. A total of 79.4% showed a postoperative astigmatic value less than 1 D. Clinical refraction was significantly reduced from -1.39 ± 0.79 D preoperatively to -0.86 ± 0.67 D postoperatively (p 0.02). A positive reduction in topographic astigmatism was also observed (p < 0.00). The best-corrected visual acuity increased postoperatively (p < 0.001). We can conclude that customised simulations based on corneal biomechanics are a valuable tool for correcting mild astigmatism with corneal incisions in cataract surgery to improve postoperative visual outcomes.

Abstract 444: Effectiveness Of The Ratio Of L-cysteine To L-glutathione In Serum For Prediction Of Cardiovascular Events

Background: Aminothiols play an important role in the antioxidant defense system and the profile may be a predictor of prognosis and cardiovascular events. Methods: Two hundred sixty-two patients (202 men, 60 women, age 65 ± 13 years) undergoing coronary catheterization were followed up to 10 years. The patients were divided equally into two groups according to the median ratio of total L-cysteine to total L-glutathione (tCys/tGSH) in serum at enrollment. Results: During 5.5 ± 3.2 years, 31 patients (12%) died, of whom 20 (8%) had cardiovascular death and 32 (12%) had MACE. In addition, 29 (11%) were hospitalized for heart failure. Log-rank test showed that the high group (tCys/tGSH&gt;=80.70) had a higher mortality from all causes (Fig.A, p=0.025) than the low group (tCys/tGSH&lt;80.70). Univariate COX regression analysis showed that tCys/tGSH was a predictive marker of death, cardiovascular death, MACE, and heart failure (p&lt;0.001, all), but these aminothiol alone did not predict any of these endpoints. After adjustment for age, sex, body mass index, coronary risk factors, renal function, and log-transformed brain natriuretic peptide, tCys/tGSH had predictive value for death (p=0.007), cardiovascular death (p=0.019), and heart failure (p=0.004). The adjusted hazard ratio for heart failure in the high tCys/tGSH group versus the low tCys/tGSH group was 3.071 (95% confidence interval: 1.186-7.952), p=0.021. tCys/tGSH ratio can be substituted by the GSH index obtained from the approximation curve (Fig.B, GSH index=142.7255*tGSH -0.777682 ). GSH index was also a prognostic biomarker, but we found tCys information was necessary to predict heart failure and was lost in GSH index. In addition, γ-glutamyl transpeptidase (GGT), which is responsible for extracellular catabolism of GSH to Cys, was a prognostic factor. Conclusions: Our results suggest that tCys and tGSH can be a useful marker of cardiovascular events by ratioing and may be an indicator of GGT activity.

Inovativna metoda za krivulje inkrementalne dinamičke analize djelomično izoliranih mostova

This paper proposes an innovative method for determining the approximate incremental dynamic analysis curves of semi-isolated bridges, including the derivation of statistical mathematical formulas. Ultimately, an innovative method is devised based on the primary and limit state tangential stiffness values of semi-isolated bridges. The bridges selected for this study are two reinforced concrete highway bridges in the United States, which have been optimally re-designed using lead rubber bearing isolators. The established procedure can be used in future studies to extract the probabilistic responses of semi-isolated bridges via a simplified and efficient method.