Bernoulli's Method Research Articles

Simulation studies on the hemodynamic models for blood flow

Abstract One of the most important fluid flows is blood flow seen in hemodynamics, which is a vital process and carries many ingredients from one place to another in the interior of the body. Blood is a special suspension; it is a non-Newtonian fluid as the blood flow cannot be compressed due to the imbalance in strain force and velocity. The blood flow is modelled by various equations which are based on fundamental equations such as the Korteweg-De Vries (KdV) equation and the nonlinear Schrödinger type equations. In this study, some new solitary solutions of the blood flow models are obtained in explicit form via Bernoulli method which is one of the ansatz-based methods. Moreover, 3D and 2D simulations under the suitable values of the parameters of the solutions obtained are plotted.

Studies on electromagnetic waves for ferromagnetic materials

With the developing technology, magneto-optical and ferromagnetic materials are gaining importance and are used especially in magneto-optics, ferromagnetism, fluid mechanics, etc. These processes are modeled via Kadomtsev–Petviashvili-type models. In this work, a generalized (3+1)-dimensional variable-coefficient modified Kadomtsev–Petviashvili (vcmKP) system and special cases are considered that simulates electromagnetic, water, and powder-acoustic/ion-acoustic/dust-ion-acoustic waves. As to the novelty of this paper, the travelling wave, soliton solutions of the considered systems are hold by using Bernoulli method which is the well-known ansatz-based method and the analytical method. As far as we know, the obtained solutions are seen for the first time in this study and are important for the development of the use of magneto-optical and ferromagnetic materials in industry and applied sciences, fiber optic communication fields.

Solitons of the Twin-Core Couplers with Fractional Beta Derivative Evolution in Optical Metamaterials via Two Distinct Methods

The rapid advancements in metamaterial research have brought forth a new era of possibilities for controlling and manipulating light at the nanoscale. In particular, the design and engineering of optical metamaterials have created advances in the field of photonics, enabling the development of advanced devices with unprecedented functionalities. Among the myriad of intriguing metamaterial structures, the nonlinear directional couplers with beta derivative evolution have emerged as a significant avenue of exploration, offering remarkable potential for light propagation and manipulation. This study obtains the solitary wave solutions for twin-core couplers having spatial-temporal fractional beta derivative evolution by using two different methods, the Bernoulli method and the complete polynomial discriminant system method. By graphing some of the obtained solutions, the effect of the beta derivative has been shown. The findings would be beneficial to understand physical behaviours in nonlinear optics, particularly twin-core couplers with optical metamaterials.

Islamic Perspective in E-Service Quality-based Knowledge Sharing on Islamic Hospital Employee Performance Improvement

Technological developments now greatly affect the activities of health organizations and are expected to encourage better hospital performance. One of the efforts that can be made to increase employee knowledge related to technological developments is through knowledge sharing. Measuring the quality of hospital management information systems from the user’s point of view using the e-service quality method. The study aims to determine the effect of knowledge sharing and e-service quality information systems on employee performance in Islamic hospitals that have followed global budget rules in West Java. This research uses a quantitative method with a causal research type. Information is collected directly from the field to find out the opinion of the respondents on the object being studied. The researchers used judgment sampling with the number of samples obtained using the Bernoulli method with an error of 5% so that the minimum number of respondents was 128. The research data were obtained through the results of interviews and questionnaires. The data were processed, analyzed, and then conclusions were drawn using the cross-sectional method. The results of the analysis show that both knowledge sharing and e-service quality are in good category and employee performance is in the very good category. The variables of knowledge sharing and e-service quality both partially and simultaneously have a positive and significant effect on employee performance with a moderate effect.
 Keywords: e-service quality, employee performance, Islamic hospital, knowledge sharing

Analytical solution for dynamic responses of offshore wind turbines supported by pipe pile in radially heterogeneous soil

Offshore wind turbines (OWTs) are subject to the combined action of dynamic environmental loads including wind, waves, and earthquake loads. This paper proposes an analytical solution for the dynamic response of OWTs supported by pipe pile in heterogeneous viscoelastic soil. The analytical model accounts for various interactions that affect OWTs dynamic response. The pipe pile-internal soil is calculated by utilizing the Helmholtz method, the pipe pile-external soil is calculated by utilizing the transfer matrix method, the pipe pile-wave is evaluated by utilizing the diffraction wave theory, and the tower drum-wind is calculated by utilizing the Bernoulli method. The dynamic responses of the pipe pile and tower are established by enforcing the boundary conditions of the displacement continuity and stress equilibrium. The developed analytical solution is degenerated into simplified analytical solutions under various conditions, which was validated by comparing its predictions with the results of available numerical and analytical solutions. The validated simplified solution is then utilized investigate the effects of some critical parameters on OWTs response. The results show that the OWTs response under the combined action of earthquake, wave and wind loads is strongly affected by the presence of water and soil inside the pipe pile, soil radial heterogeneity.

Model comparison and effect of flow and accessories on the pressure drop of the unit ff-df-270/el of Universidad de Cartagena

The effect of flow variation on the theoretical calculation of pressure drop in pipes with fittings in the unit FF-DF-270/EL of the Universidad de Cartagena was studied, determining the coefficient of minor losses (Kf) caused by 45° and 90° elbows, and three types of valves, using water as the process fluid. The flow rate (Q) was varied, using a valve, between 24, 20, 16, 12 L/min. Darcy's and Bernoulli's theorem methods were used to evaluate friction losses. Were found minimum error percentages of 0.04% and maximum 8.16%; loss coefficients adjusted by minimum squares were obtained with R2 of 0.999, comparing these Kf with the values reported in the plant manual and different authors. It was shown experimentally that the loss coefficient depends on each fitting, allowing the calculation of the theoretical pressure drop and comparing it with the experimental pressure drop, demonstrating that as the flow increases, an increase in pressure drop is generated. With the methodology applied in this research, the aim is to optimize pressure drop tests with fittings, and identify the characteristics of the pipe to obtain an optimum lower loss coefficient value.

A symmetric version of the Euler equations by using Generalized Bernoulli Method

The aim of this article is to show a way to extend the usefulness of the Generalized Bernoulli Method (GBM) with the purpose to apply it for the case of variational problems with functionals that depend explicitly of all the variables. Moreover, after expressing the Euler equations in terms of this extension of GBM, we will see that the resulting equations acquire a symmetric form, which is not shared by the known Euler equations. We will see that this symmetry is useful because it allows us to recall these equations with ease. The presentation of three examples shows that by applying GBM, the Euler equations are obtained just as well as it does the known Euler formalism but with much less effort, which makes GBM ideal for practical applications. In fact, given a variational problem, GBM establishes the corresponding Euler equations by means of a systematic procedure, which is easy to recall, based in both elementary calculus and algebra without having to memorize the known formulas. Finally, in order to extend the practical applications of the proposed method, this work will employ GBM with the purpose to apply it for the case of solving isoperimetric problems.

Forceful interaction of the casing string with the walls of a curvilinear well

Purpose. Developing a method for determining the axial forces and the walls reactions along a casing string, which bend it and make it follow a curved wellbore shape. Methodology. The casing string is represented as a long elastic rod in the curved well. An inhomogeneous system of four differential equations is developed to describe the rods deformations. It was reduced to a first-order differential equation with respect to axial force. Its solution was found by the Bernoulli method. The numerical integration of the differential equation is applied. Findings. The axial force distribution along the casing string was found, taking into account the well curvature and the friction, as well as the reaction forces of the well walls. A method of the tables numerical integration of the wells inclinometric measurements has been developed. The calculating formulas for the reaction forces, axial forces, bending moments and stresses acting in the casing pipes in the well deep are obtained. Originality. The solved problem takes into account the walls reaction and the friction forces that create longitudinal bend during the columns movement. The system of differential equations of equilibrium was supplemented by Eulers kinematic equation. The function of zenith angle, which is known due to the table of the directional survey data, was taken as the integration variable. The inverse problem is solved all unknown internal forces, also such the external distributed reaction, which causes the column to repeat the wells shape, was been determined by the angular deformations of casing string, which are given by the wells shape in the inclinometric table. Practical value. The developed method allows detecting the areas with a significant local increase in the wells curvature, which indicate their obstructed passability. This allows for accurate determination of depth intervals to increase the borehole diameter, which is necessary before lowering the column. According to the analysis results, it is possible to determine the parameters of the stress-strain state of the casing string, which can be used to predict its working capacity and operating life.

Determinants and spatial distribution of institutional delivery in Ethiopia: evidence from Ethiopian Mini Demographic and Health Surveys 2019

BackgroundOver the past few decades, maternal and child mortality had drawn the attention of governments and policymakers. Institutional delivery has been among the implementations needed to reduce maternal and child mortality. The fact that the problem was persisted intensified studies to research for more factors. Thus, the current study was intended for further analyses of EMDHS to identify the magnitude, spatial patterns, and predictors of institutional delivery.MethodsA cross-sectional survey data from EMDHS 2019 was analyzed involving 5488 reproductive-age women regarding institutional deliveries. We presented descriptive statistics using mean, standard deviations, and proportions. To check the nature of the distribution of institutional delivery, we applied the global Moran’s I statistics. Getis-Ord Gi statistics was applied to detect spatial locations, and we applied spatial interpolation to predict unknown locations of institutional delivery using the Ordinary Kriging method. Kulldorff’s SatScan was also applied to identify the specific local clustering nature of institutional delivery using the Bernoulli method. We applied multilevel binary logistic regression for the scrutiny of individual and community-level factors. We applied P < 0.25 to include variables in the model and P < 0.05 to declare associations. AOR with 95% CI was used to describe variables.ResultsThe prevalence of institution/facility delivery was 2666.45(48.58%) in the survey. The average number of children was 4.03 ± 2.47, and most women in this survey were in the age range of the 25-29 years (31.84%) and 30–34 years (21.61%). Women who learned primary education (AOR = 1.52; 95% CI 1.20–1.95), secondary education (AOR = 1.77; 95% CI 1.03–3.07), and higher education (AOR = 5.41; 95% 1.91–15.25), while those who can read and write sentences (AOR = 1.94; 95% 1.28–2.94), Rich (AOR = 2.40 95% CI 1.82–3.16), and those followed 1–2 ANC (AOR = 2.08; 95% CI 1.57–2.76), 3 ANCs (AOR = 3.24; 95% CI 2.51–418), and ≥ 4 ANCs (AOR = 4.91; 95% CI 3.93–6.15) had higher odds of delivering at health institutions.ConclusionThe institutional delivery was unsatisfactory in Ethiopia, and there were various factors associated differently across the different regions. Pastoralist regions showed high home delivery than institutions which invites further interventions specific to those regions. Factors like age, highest education level achieved, preceding birth interval, literacy status, wealth status, birth order, regions, and rural residences were all affected institutional delivery so that interventions considering awareness, access, and availability of the services are vital.

Closed-form solutions for vibrations analysis of cracked Timoshenko beams on elastic medium: An analytically approach

In this paper a novel analytically method for analysing the dynamic behaviour of Timoshenko beam model, resting on Winkler-type elastic soil, under simply-supported boundary condition and with a crack is proposed. The beam is also supposed to be constrained at the ends by elastically flexible springs, with transverse stiffness and rotational stiffness. Applying the Timoshenko beam theory and employing the auxiliary functions, the equation of motion is derived. The natural frequencies are obtained by applying the Euler–Bernoulli method and are derived by the corresponding auxiliary functions of the governing equation of the Euler–Bernoulli beam in free vibration. For different values of soil parameter, taking into account the effects of rotational and shear deformation and considering the presence of crack, typical results are presented, in order to demonstrate the efficiency of the proposed approach. Finally the obtained results are compared with some results available in the literature. It is shown that very good results are obtained. This approach is very effective for the study of vibration problems of Timoshenko beams. The novelty of the proposed approach is that although the auxiliary functions, used to find the solution to the dynamic problem of a Timoshenko beam, are different for the two theories applied, in both cases, the dynamic problem is traced to the study of an Euler - Bernoulli beam subjected to an axial load.

Dynamic analogy between Timoshenko and Euler–Bernoulli beams

In this paper, a novel analytically method for analyzing the dynamic behavior of beams, under different boundary conditions and in presence of cracks, is proposed. Applying the Timoshenko beam theory and introducing the auxiliary functions, the equation of motion is derived using the Hamiltonian approach. The natural frequencies are obtained by applying the Euler–Bernoulli method and are derived by the corresponding auxiliary functions of the governing equation of the Euler–Bernoulli beam in free vibration. In order to demonstrate the efficiency of the proposed approach, typical results are presented and compared with some results available in the literature. Different boundary conditions were considered, and natural frequencies were calculated and compared. It is shown that very good results are obtained. This approach is very effective for the study of the vibration problem of Timoshenko beams. The novelty of the proposed approach is that although the auxiliary functions are different for the two theories, in both cases the dynamic problem is traced to the study of an Euler–Bernoulli beam subjected to an axial load.

A practical proposal to obtain solutions of certain variational problems avoiding Euler formalism

The aim of this article is to show the way to get both, exact and analytical approximate solutions for certain variational problems with moving boundaries but without resorting to Euler formalism at all, for which we propose two methods: the Moving Boundary Conditions Without Employing Transversality Conditions (MWTC) and the Moving Boundary Condition Employing Transversality Conditions (METC). It is worthwhile to mention that the first of them avoids the concept of transversality condition, which is basic for this kind of problems, from the point of view of the known Euler formalism. While it is true that the second method will utilize the above mentioned conditions, it will do through a systematic elementary procedure, easy to apply and recall; in addition, it will be seen that the Generalized Bernoulli Method (GBM) will turn out to be a fundamental tool in order to achieve these objectives.

Persian Text Classification using naive Bayes algorithms and Support Vector Machine algorithm

One of the several benefits of text classification is to automatically assign document in predefined category is one of the primary steps toward knowledge extraction from the raw textual data. In such tasks, words are dealt with as a set of features. Due to high dimensionality and sparseness of feature vector results from traditional feature selection methods, most of the proposed text classification methods for this purpose lack performance and accuracy. Many algorithms have been implemented to the problem of Automatic Text Categorization that’s why, we tried to use new methods like Information Extraction, Natural Language Processing, and Machine Learning. This paper proposes an innovative approach to improve the classification performance of the Persian text. Naive Bayes classifiers which are widely used for text classification in machine learning are based on the conditional probability. we have compared the Gaussian, Multinomial and Bernoulli methods of naive Bayes algorithms with SVM algorithm. for statistical text representation, TF and TF-IDF and character-level 3 (3-Gram) [6,9] were used. Finally, experimental results on 10 newsgroups.

Persian Text Classification using naive Bayes algorithms and Support Vector Machine algorithm

One of the several benefits of text classification is to automatically assign document in predefined category is one of the primary steps toward knowledge extraction from the raw textual data. In such tasks, words are dealt with as a set of features. Due to high dimensionality and sparseness of feature vector results from traditional feature selection methods, most of the proposed text classification methods for this purpose lack performance and accuracy. Many algorithms have been implemented to the problem of Automatic Text Categorization that’s why, we tried to use new methods like Information Extraction, Natural Language Processing, and Machine Learning. This paper proposes an innovative approach to improve the classification performance of the Persian text. Naive Bayes classifiers which are widely used for text classification in machine learning are based on the conditional probability. we have compared the Gaussian, Multinomial and Bernoulli methods of naive Bayes algorithms with SVM algorithm. for statistical text representation, TF and TF-IDF and character-level 3 (3-Gram) [6,9] were used. Finally, experimental results on 10 newsgroups.

PERBANDINGAN KINERJA VARIASI NAÏVE BAYES MULTIVARIATE BERNOULLI DAN NAÏVE BAYES MULTINOMIAL DALAM PENGKLASIFIKASIAN DOKUMEN TEKS

Classification of text documents with large amounts will be a job that requires a lot of time, effort and cost of having to read text documents and then categorize them manually, therefore the automatic classification of text documents is needed. The algorithm developed is K-Nearest-Neighbor (KNN), Naïve Bayes, Support Vector Machine (SVM), Decision Tree (DT), Neural Network (NN) and Maximum Entropy. The algorithm used as the object of research is a variation of the Naïve Bayes algorithm, the Naïve Bayes Multivariate Bernoulli and the Naïve Bayes Multinomial. This study discusses whether there are differences between the Algorithms. The Naïve Bayes Multivariate Bernoulli algorithm and the Naïve Bayes Multinomial can be seen from the value of the agreement and the speed of the process of classifying text documents, as well as more information about the process of processing requests that are getting more and more requested. While the highest value using the non-stemming Naïve Bayes Bernoulli method is 71.33%, and the fastest processing time is required using the non-stemming Naïve Bayes method which requires 0.12 seconds processing time.

CURVE OF DESCENT OF A MATERIAL POINT IN THE SHORTEST TIME ON A TRANSCENDENTAL SURFACE IN A UNIFORM VERTICAL GRAVITATIONAL FIELD

Background. The article deals with the original variational problem of the brachystochronous motion of a material point on a cycloidal surface between two given points in a vertically homogeneous gravitational field. The novelty and relevance of the work is explained by the choice of the transcendental surface, since earlier the motion of a material point was considered on algebraic surfaces of the second order.Objective. Find a curve on the transcendental surface, moving from one set point (starting point) to another set point (finish point) on this surface without friction a material point will make such a transition in a minimum time. The transcendental surface has a guide curve of the cycloid lying in one of the coordinate planes, and its generatrix are perpendicular to that plane.Methods. To achieve this goal, we used the classical methods of variational calculus (Euler–Lagrange equation), as well as the classical method of integrating ordinary differential equations in a closed form (Bernoulli method).Results. A time functional was constructed, using which the differential equations of the spatial brachystrochron, which lies on the transcendental surface, are analytically deduced. After integration in a closed form, algebraic equations of the spatial brachystrochron in parametric form are obtained. The results of the study are illustrated graphically: the projections of the trajectory of the brachystrochron on the coordinate planes OXY and OXZ. The slope angles of the optimal trajectory at the start point are determined. A comparative analysis of the time of action in the process of motion of a material point along two trajectories is carried out: along the obtained brachystrochron and along the alternative trajectory.Conclusions. The proposed approach allows to pre-plot such a logistic route of a material point on a given transcendental surface between two fixed points, which will provide a minimum travel time between them in a uniform vertical gravity field. In this case, an extreme trajectory will not necessarily be the shortest line on the surface that connects the two predetermined points (start and finish).

Citizen science flow – an assessment of simple streamflow measurement methods

Abstract. Wise management of water resources requires data. Nevertheless, the amount of streamflow data being collected globally continues to decline. Generating hydrologic data together with citizen scientists can help fill this growing hydrological data gap. Our aim herein was to (1) perform an initial evaluation of three simple streamflow measurement methods (i.e., float, salt dilution, and Bernoulli run-up), (2) evaluate the same three methods with citizen scientists, and (3) apply the preferred method at more sites with more people. For computing errors, we used midsection measurements from an acoustic Doppler velocimeter as reference flows. First, we (authors) performed 20 evaluation measurements in headwater catchments of the Kathmandu Valley, Nepal. Reference flows ranged from 6.4 to 240 L s−1. Absolute errors averaged 23 %, 15 %, and 37 % with average biases of 8 %, 6 %, and 26 % for float, salt dilution, and Bernoulli methods, respectively. Second, we evaluated the same three methods at 15 sites in two watersheds within the Kathmandu Valley with 10 groups of citizen scientists (three to four members each) and one “expert” group (authors). At each site, each group performed three simple methods; experts also performed SonTek FlowTracker midsection reference measurements (ranging from 4.2 to 896 L s−1). For float, salt dilution, and Bernoulli methods, absolute errors averaged 41 %, 21 %, and 43 % for experts and 63 %, 28 %, and 131 % for citizen scientists, while biases averaged 41 %, 19 %, and 40 % for experts and 52 %, 7 %, and 127 % for citizen scientists, respectively. Based on these results, we selected salt dilution as the preferred method. Finally, we performed larger-scale pilot testing in week-long pre- and post-monsoon Citizen Science Flow campaigns involving 25 and 37 citizen scientists, respectively. Observed flows (n=131 pre-monsoon; n=133 post-monsoon) were distributed among the 10 headwater catchments of the Kathmandu Valley and ranged from 0.4 to 425 L s−1 and from 1.1 to 1804 L s−1 in pre- and post-monsoon, respectively. Future work should further evaluate uncertainties of citizen science salt dilution measurements, the feasibility of their application to larger regions, and the information content of additional streamflow data.

Validation of pressure drop assessment using 4D flow MRI-based turbulence production in various shapes of aortic stenoses.

To validate pressure drop measurements using 4D flow MRI-based turbulence production in various shapes of stenotic stenoses. In vitro flow phantoms with seven different 3D-printed aortic valve geometries were constructed and scanned with 4D flow MRI with six-directional flow encoding (ICOSA6). The pressure drop through the valve was non-invasively predicted based on the simplified Bernoulli, the extended Bernoulli, the turbulence production, and the shear-scaling methods. Linear regression and agreement of the predictions with invasively measured pressure drop were analyzed. All pressure drop predictions using 4D Flow MRI were linearly correlated to the true pressure drop but resulted in different regression slopes. The regression slope and 95% limits of agreement for the simplified Bernoulli method were 1.35 and 11.99 ± 21.72 mm Hg. The regression slope and 95% limits of agreement for the extended Bernoulli method were 1.02 and 0.74 ± 8.48 mm Hg. The regression slope and 95% limits of agreement for the turbulence production method were 0.89 and 0.96 ± 8.01 mm Hg. The shear-scaling method presented good correlation with an invasively measured pressure drop, but the regression slope varied between 0.36 and 1.00 depending on the shear-scaling coefficient. The pressure drop assessment based on the turbulence production method agrees well with the extended Bernoulli method and invasively measured pressure drop in various shapes of the aortic valve. Turbulence-based pressure drop estimation can, as a complement to the conventional Bernoulli method, play a role in the assessment of valve diseases.

Two Very Accurate and Efficient Methods for Solving Time-Dependent Problems

In this paper, collocation method based on Bernoulli and Galerkin method based on wavelet are proposed for solving nonhomogeneous heat and wave equations. The two methods have the linear systems solved by suitable solvers. Several examples are given to examine the performance of these methods and a comparison is made.

Optical solitons and conservation law of Kundu–Eckhaus equation

This paper obtains optical soliton solutions to the Kundu–Eckhaus equation with general coefficients. The Riccati–Bernoulli's sub-ODE method as well as Kudryashov's scheme are employed to obtain soliton solutions to the model. This generalized earlier reported result of the model with specific coefficients. Subsequently, the multiplier approach was utilized to secure a conserved quantity with the bright soliton solution that was reported earlier.