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Prediction of oil flow rate through an orifice flow meter: Artificial intelligence alternatives compared

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Petroleum 2020年第4期6卷 404-414页

作者： Hamzeh Ghorbani David A.Wood Abouzar Choubineh afshin tatar Pejman Ghazaeipour Abarghoyi Mohammad Madani Nima Mohamadian Young Researchers and Elite Club Ahvaz BranchIslamic Azad UniversityAhvazIran DWA Energy Limited LincolnUnited Kingdom Petroleum Department Petroleum University of TechnologyAhwazIran Young Researchers and Elite Club North Tehran BranchIslamic Azad UniversityTehranIran National Iranian South Oil Company(NISOC) AhvazIran Young Researchers and Elite Club Omidiyeh BranchIslamic Azad UniversityOmidiyehIran

Fluid-flow measurements of petroleum can be performed using a variety of equipment such as orifice meters and wellhead *** is useful to understand the relationship between flow rate through orifice meters(Qv)and the five fluid-flow influencing input variables:pressure(P),temperature(T),viscosity(μ),square root of differential pressure(ΔP^0.5),and oil specific gravity(SG).Here we evaluate these relationships using a range of machine-learning algorithms applied to orifice meter data from a pipeline flowing from the Cheshmeh Khosh Iranian oil *** coefficients indicate that(Qv)has weak to moderate positive correlations with T,P,andμ,a strong positive correlation with theΔP^0.5,and a weak negative correlation with oil specific *** order to predict the flow rate with reliable accuracy,five machine-learning algorithms are applied to a dataset of 1037 data records(830 used for algorithm training;207 used for testing)with the full input variable values for the data set *** algorithms evaluated are:Adaptive Neuro Fuzzy Inference System(ANFIS),Least Squares Support Vector Machine(LSSVM),Radial Basis Function(RBF),Multilayer Perceptron(MLP),and Gene expression programming(GEP).The prediction performance analysis reveals that all of the applied methods provide predictions at acceptable levels of *** MLP algorithm achieves the most accurate predictions of orifice meter flow rates for the dataset *** and RBF also achieve high levels of *** and LSSVM perform less well,particularly in the lower flow rate range(i.e.,<40,000 stb/day).Some machine learning algorithms have the potential to overcome the limitations of idealized streamline analysis applying the Bernoulli equation when predicting flow rate across an orifice meter,particularly at low flow rates and in turbulent flow *** studies on additional datasets are required to confirm this.

关键词： Orifice flow meters Flow-rate-predicting virtual meters Multiple machine-learning algorithm comparisons Metrics influencing oil flow Flow-rate prediction error analysis

EXPONENTIAL DECAY FOR A VISCOELASTICALLY DAMPED TIMOSHENKO BEAM

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Acta Mathematica Scientia 2013年第2期33卷 505-524页

作者： N. tatar King Fahd University of Petroleum and Minerals Department of Mathematics & StatisticsDhahran 31261Saudi Arabia

Of concern is a viscoelastic beam modelled using the Timoshenko theory. It is well-kimwn that the system is exponentially stable if the kernel in the memory term is sub- exponential. That is, if the product of the kernel with an exponential function is a summable function. In this article we address the questions： What if the kernel is tested against a different function （say Gamma） other than the exponential function？ Would there still be stability？ In the affirmative, what kind of decay rate we get？ It is proved that for a non- decreasing function ＂Gamma＂ whose ＂logarithmic derivative＂ is decreasing to zero we have a decay of order Gamma to some power and in the case it decreases to a different value than zero then the decay is exponential.

关键词： Arbitrary decay memory term relaxation function Timoshenko beam vis-coelasticity

FRACTIONAL HALANAY INEQUALITY AND APPLICATION IN NEURAL NETWORK THEORY

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Acta Mathematica Scientia 2019年第6期39卷 1605-1618页

作者： Nasser-eddine tatar King Fahd University of Petroleum and Minerals Department of Mathematics and Statistics

The (integer order) Halanay inequality with distributed delays is extended to the fractional order case. It is proved that solutions decay to zero as a Mittag-Leffler function as time goes to infinity provided that the delay feedback are bounded by similar *** application to a problem arising in neural network theory is provided showing that the equilibrium is Mittag-Leffler stable.

关键词： Hopfield neural network Mittag-Leffler stability Caputo fractional derivative fractional Halanay inequality

High Performance Liquid Chromatography for the Determina- tion of Metoclopramide in Pharmaceutical Preparations Using Pre-column Derivatization with Fluorescamine

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Chinese Journal of Chemistry 2012年第3期30卷 634-638页

作者： tatar Ulu,Sevgi Department of Analytical Chemistry Faculty of PharmacyIstanbul UniversityIstanbul34416Turkey

A simple, rapid and sensitive high performance liquid chromatography （HPLC） method was developed for the determination of metoclopramide in pharmaceutical preparation. The method is based on the derivatization of metoclopramide with fluorescamine. The separation was achieved on a C18 column using methanol-water （70 ： 30, V/V） mobile phase. Fluorescence detector was used at the excitation and emission of 403 and 485 nm, respectively. The method was validated for linearity, limit of detection, limit of quantification, precision, accuracy, recovery, robust- ness and system suitability. The assay was linear over the concentration range of 100-2000 ng/mL. The mean recovery was 100.37%. The proposed method was successfully applied to the assay of metoclopramide in tablet preparation. The preparation was also analyzed with an official method and statistical comparison by t- and F-tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.

关键词： metoclopramide fluorescamine validation HPLC derivatization determination

Determination of Ciprofloxacin in Human Plasma and Urine by Precolumn Derivatization High Performance Liquid Chromatography with Fluorescence Detection

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Chinese Journal of Chemistry 2011年第6期29卷 1256-1260页

作者： Ulu, Sevgi tatar Department of Analytical Chemistry Faculty of Pharmacy University of lstanbul 34416 Istanbul Turkey

A sensitive, simple and selective high-performance liquid chromatographic （HPLC） method was developed for the determination of ciprofloxacin in biological fluids. The method is based on the reaction between the drug and 4-chloro-7-nitrobenzofurazan （NBD-C1） in borate buffer of pH 9.0 to yield a highly fluorescent derivative that is measured at 535 nm after excitation at 464 nm. The calibration curves were linear over the concentration ranges of 25--3000 and 50--3000 ng·mL -1 for plasma and urine, respectively. The mean recovery of ciprofloxacin from plasma and urine was 98.37% and 98.40%, respectively. The method was found to be sensitive, precise, accurate, and reproducible. All of the validation parameters were within the acceptance range.

关键词： high-performance liquid chromatographic (HPLC) ciprofloxacin derivatization 4-chloro-7-nitrobenzofurazan validation biological fluids

Sensitive Spectrofluorimetric Method of Analysis for Gabapentin in Pure and Pharmaceutical Preparations

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Chinese Journal of Chemistry 2011年第3期29卷 562-566页

作者： Ulu, Sevgi tatar Kel, Elif Department of Analytical Chemistry Faculty of Pharmacy Istanbul University 34416 Istanbul Turkey

Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabapentin with 4-fluoro-7-nitrobenzofurazan （NBD-F） in an alkaline medium （pH 9.5） to form a highly fluorescent derivative that was measured at 521 nm after excitation at 458 rim. The factors affecting the reaction was carefully studied and optimized. The method was successfully validated for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and specificity. Under the optimized conditions, linear relationship with good correlation coefficient （0.9998） was found between the relative fluorescence intensity and gabapentin concentration in the range of 10--100 ng·mL^-1. The limit of detection and limit of quantification were 0.43 and 1.30 ng·mL ^-1, respectively. The proposed method was successfully applied to the determination of gabapentin in its pharmaceutical capsules. The results obtained by the proposed method were comparable with those obtained by the official method. Statistical comparison by t- and F- tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.

关键词： gabapentin NBD-F spectrofluorimetric method derivatization determination

ELASTIC MEMBRANE EQUATION WITH MEMORY TERM AND NONLINEAR BOUNDARY DAMPING:GLOBAL EXISTENCE,DECAY AND BLOWUP OF THE SOLUTION

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Acta Mathematica Scientia 2013年第1期33卷 84-106页

作者： Abderrahmane ZARA Nasser-eddine tatar Salem ABDELMALEK Depatment of Mathematics and Informatic Cheikh El Arbi Tébessi University12002 TébessaAlgeria Depatment of Mathematics and Statistics King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Depatment of Mathematics College of SciencesYanbuTaibah UniversitySaudi Arabia

In this paper we consider the Elastic membrane equation：with memory term and nonlinear boundary damping： Under some appropriate assumptions on the relaxation function h and with certain initial data, the global existence of solutions ：and a general decay for the energy are established using the multiplier technique. Also, ＇we show that a nonlinear source of polynomial type is able to force solutions to blow up in finite time even in presence of a nonlinear damping.

关键词： elastic membrane equation global existence boundary damping boundarysource general decay blowup

Unusual colonoscopy finding:Taenia saginata proglottid

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World Journal of Gastroenterology 2007年第41期13卷 5540-5541页

作者： Nayan M Patel Eric L tatar University of Medicine and Dentistry of NJ Robert Wood Johnson Medical SchoolDepartment of Internal MedicineNew BrunswickNJ 08901United States

Infection with tapeworms is a major problem in many parts of the world. Patients may be asymptomatic or have a significant morbidity depending on the species. Infection with Taenia species is sometimes found by expulsion of eggs or proglottids in stool. Species specific diagnosis of Taenia is difficult,but possible. We present a case of Taenia saginata incidentally discovered,and risk factors for transmission,diagnosis,symptoms,and treatment.

关键词： Taenia saginata colonoscopy Tapeworm

Comparison via Digital Radiography of Radiopacity Levels of Composite Materials with Various Shades and Viscosities

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Journal of Wuhan University of Technology(Materials Science) 2022年第2期37卷 170-176页

作者： Gunce Ozan Oktay Yazicioglu Hidir tatar Sevda Ozel Yildiz Istanbul University Faculty of Dentistry Dept.of Restorative Dentistry Haseki Education and Research Hospital Istanbul University Faculty of Medicine Dept.of Biostatistics

Aim of the present in vitro study is to evaluate the radiopacity levels of composite resins with various shades and viscosity.10 mm×2 mm discs were prepared from 7 condensable and 4 flowable composites(n=10).An aluminum step wedge ranging from 2.0 to 10.0 mm in thickness was placed on the occlusal *** radiographs were taken using a dental X-ray device and radiographic densities of each step of the aluminum wedge and the samples were recorded to the *** readings were taken and means were ***-Way Anova and Tamhane post hoc tests were *** G-eanial Posterior has the highest radiopacity value followed by Filtek Z550,Aelite Flo has the lowest radiopacity *** composites show higher radiopacity and flowable composites with higher filler loadings have superior radiopacity levels to condensable *** and body shades of the composite brands have also statistically significant differences in radiopacity ***,radiopacity level of a composite resin material is not affected by the size of fillers;however,the composition,shape and loading of the fillers can specify the radiodensity.

关键词： radiopacity composite resins digital radiography flowable composites shade