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Automated dual source systems for measurement of DC resistance standards

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Journal of measurement science and Instrumentation 2019年第2期10卷 109-115页

作者： rasha s m ali m Helmy A Raouf Dept.of Electrical Quantities metrology National Institute for Standards(NIS)Giza 12211-136Egypt

A new system for measuring low-ohmic standard resistors through a dual current sources bridge is *** is used for low resistance measurements from 1 mΩto 1Ωat 1∶1 ratio,which is suitable for the laboratories without cryogenic current comparators(CCC)or direct current comparators(DCC)*** of this bridge is evaluated by comparing its measured values with the unknown resistor values obtained by another *** accuracy of the introduced bridge is in the level of 10-5 for the 1 mΩresistor,and in the level of 10-4 for the 10 mΩ,100 mΩand 1Ω***,a dual voltage sources system for the measurement of DC standard resistors from 1 kΩto 100 mΩis also *** this system,a modification is made on the modified Wheatstone bridge to evaluate its performance by adding another digital multimeter to measure the ratio between the unknown and the standard resistors *** bridge is verified by comparing the measured values of 10 kΩresistor obtained by the two methods with its actual *** bridge accuracy is in the level of 10-6 except for the 1 kΩresistor,and the bridge asymmetry is also *** is found the asymmetry is in the level of 10-6 for the resistors from 10 kΩto 100 mΩand in the level of 10-5 for 1 kΩ*** introduced bridges operations are controlled by LabVIEW programs designed specially for this purpose,and the expanded uncertainty is also evaluated for all measurement results.

关键词： direct current comparators voltage null detector modified Wheatstone bridge ratio technique resistance measurements uncertainty

Fabrication of automatic switch for AC-DC completely automated measurement system at NIs

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Journal of measurement science and Instrumentation 2017年第1期8卷 27-31页

作者： m Helmy A Raouf rasha s m ali 国家标准化研究所电量计量部埃及吉萨12211-136

A fast automatic AC-DC switch is designed and fabricated mainly by a microcontroller and three double poles single throw reed *** new switch is introduced to establish a fully automated system for AC-DC measurements through ACDC transfer standards for the first time at the National Institute for standards(N Is)in *** implemented circuit of theautomatic AC-DC switch and its protection are presented in *** AC voltage source is calibrated against DC voltagesource by using the demonstrated automatic switch as an application The calibrated voltage ranges are2V,6V,20V and60V as *** uncertainty budget is also evaluated for the calibrated values.

关键词： AC voltage measurement AC-DC transfer standard automatic switching system uncertainty

Establishment of Automated multi-Range multipliers Combined with TVC

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Journal of measurement science and Instrumentation 2011年第3期2卷 297-299页

作者： rasha s.m.ali m.Helmy A.Raouf Dept.of Electrical Quantities metrology National Institute of Standards

An automated multi-range multipliers（range resistors）system is established for the AC voltage measurements by using a thermal voltage *** is performed automatically by selecting the appropriate multiplier whose voltage range contains the voltage to be measured without changing it manually through a new designed *** consists of control part through a micro-controller controlled by specified prepared Lab-VIEW program and switching part through electronic relays in one circuit as clearly described in this *** is used for measuring the ac voltage in the range from 1 V to 200 ***,it can be used for the voltage ranges up to 1 000 V by putting some factors into *** AC-DC transfer differences for these multipliers combined with thermal voltage converter are determined automatically against another standard thermal voltage converter by using another Lab-VIEW program.

关键词： AC voltage measurement thermal voltage converter AC-DC transfer standard multipliers uncertainty

Current dependence coefficient determination for different DC standard resistors measurements based on Ⅴ-Ⅰ method

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Journal of measurement science and Instrumentation 2016年第4期7卷 332-335页

作者： rasha s m ali m Helmy A Raouf Department of Electrical Quantities metrology National Institute for Standards （NIS）Giza 12211-136 Egypt

Current dependence and stability of the measured resistance value are very important for the accurate measurement of DC standard resistor. In this paper, the volt-ampere （V-I） measurement method has been applied to study the current depend-ence of four different types of standard resistors. Diverse values are obtained through the investigation of their stability at dif-ferent currents. Therefore, the current dependence coefficient （CDC） can be determined for each one of the studied resistors. Research shows CDC depends on the applied current value, the measurement time and the resistor type, as clearly demonstra-ted in this research.

关键词： current dependence coefficient standard resistors volt-ampere method resistor stability

Automated multi-meter method for the scaling of Low AC Voltage from 200 mV to 2 mV

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Energy and Power Engineering 2013年第2期5卷 129-134页

作者： rasha s. m. ali Hala A. mageed N. N. Tadros Electrical Quantities Laboratory National Institute for Standards (NIS) Giza Egypt

A set of seven single junction thermal converter micropotentiometers (μPots) has been constructed at the National Institute for standards (NIs), Egypt. This set has been built to cover the low ac voltage ranges from 2 mV to 200 mV at frequencies from 40 Hz up to 20 kHz. The construction of the μPots set has been presented and an adopted calibration method has been performed as well. This method has been performed by means of a step-down procedure using a Digital multi-meter (Dmm). The scaling procedures have been carried out in sequential steps starting from the calibration of the 200 mV-μpot by using Dmm that is accurately calibrated at its 200 mV ac voltage range down to 2 mV-μPot. Furthermore, a new automatic calibration system has been established to achieve the scaling procedures. This system has been specially designed using Laboratory Virtual Instrument Engineering Workbench (LabVIEW) software to overcome the deficiencies of manual methods. The automatic calibration has been investigated of all mPots at different frequencies. The ac-dc differences for the μPots and their uncertainty evaluation from 2 mV to 200 mV at different frequencies from 40 Hz to 20 kHz have been determined.

关键词： micropotentiometer Low ac Voltage Calibration ac-dc Difference Digital multimeter step Down Procedure

Using neural network modeling to improve the detection accuracy of land subsidence due to groundwater withdrawal

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Journal of mountain science 2024年第7期21卷 2320-2333页

作者： ali m.RAJABI ali EDALAT Yasaman ABOLGHAsEmI mahdi KHODAPARAsT Department of Engineering Geology University of TehranTehran ***Iran Department of Civil Engineering University of QomQom ***Iran

Despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that affect the accuracy of the *** paper proposes a method based on an artificial neural network to improve the results of monitoring land subsidence due to groundwater overexploitation by radar interferometry in the aliabad plain(Central Iran).In this regard,vertical ground deformations were monitored over 18 months using the sentinel-1A sAR *** model the land subsidence by a multilayer perceptron(mLP)artificial neural network,four parameters,including groundwater level,alluvial thickness,elastic modulus,and transmissivity have been *** model's generalizability was assessed using data derived for 144 *** to the results,the neural network estimates the land subsidence at each ground point with an accuracy of 6.8 mm.A comparison between the predicted and actual values indicated a significant *** mLP model can be used to improve the results of subsidence detection in the study area or other areas with similar characteristics.

关键词： DInsAR Land subsidence Groundwater withdrawal aliabad plain Artificial neural network

Arrhythmia Detection by Using Chaos Theory with machine Learning Algorithms

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Computers, materials & Continua 2024年第6期79卷 3855-3875页

作者： maie Aboghazalah Passent El-kafrawy Abdelmoty m.Ahmed rasha Elnemr Belgacem Bouallegue Ayman El-sayed math and Computer science Department Faculty of ScienceMenoufia UniversityShebin El-komEgypt College of Engineering Computer Science DepartmentEffat UniversityJeddahKingdom of Saudi Arabia Department of Computer Engineering College of Computer ScienceKing Khalid UniversityAbha61421Saudi Arabia Computer science and Engineering Department Faculty of Electronic EngineeringMenoufia UniversityShebin El-komEgypt Climate Change Information Center and Expert systems Agriculture Research CenterGizaEgypt

Heart monitoring improves life ***(ECGs or EKGs)detect heart *** learning algorithms can create a few ECG diagnosis processing *** first method uses raw ECG and time-series *** second method classifies the ECG by patient *** third technique translates ECG impulses into Q waves,R waves and s waves(QRs)features using richer *** ECG signals vary naturally between humans and activities,we will combine the three feature selection methods to improve classification accuracy and *** using all three approaches have not been examined till *** researchers found that machine Learning(mL)techniques can improve ECG *** study will compare popular machine learning techniques to evaluate ECG *** algorithms—support Vector machine(sVm),Decision Tree,Naive Bayes,and Neural Network—compare categorization *** plus prior knowledge has the highest accuracy(99%)of the four mL *** characteristics failed to identify signals without chaos *** 99.8%classification accuracy,the Decision Tree technique outperformed all previous experiments.

关键词： ECG extraction ECG leads time series prior knowledge and arrhythmia chaos theory QRs complex analysis machine learning ECG classification

metabolic complications of psychotropic medications in psychiatric disorders:Emerging role of de novo lipogenesis and therapeutic consideration

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World Journal of Psychiatry 2024年第6期14卷 767-783页

作者： mohammad m Khan Zaw ali Khan mohsin ali Khan Laboratory of Translational Neurology and molecular Psychiatry Department of BiotechnologyEra’s Lucknow Medical College and Hospitaland Faculty of ScienceEra UniversityLucknow 226003India Era’s Lucknow medical College and Hospital Era UniversityLucknow 226003India

Although significant advances have been made in understanding the pathophysiology of psychiatric disorders(PDs),therapeutic advances have not been very *** psychotropic medications can reduce classical symptoms in patients with PDs,their long-term use has been reported to induce or exaggerate various pre-existing metabolic abnormalities including diabetes,obesity and non-alcoholic fatty liver disease(NAFLD).The mechanism(s)underlying these metabolic abnormalities is not clear;however,lipid/fatty acid accumulation due to enhanced de novo lipogenesis(DNL)has been shown to reduce membrane fluidity,increase oxidative stress and inflammation leading to the development of the aforementioned metabolic ***,emerging evidence suggest that DNL dysregulation and fatty acid accumulation could be the major mechanisms associated with the development of obesity,diabetes and NAFLD after long-term treatment with psychotropic medications in patients with *** support of this,several adjunctive drugs comprising of anti-oxidants and antiinflammatory agents,that are used in treating PDs in combination with psychotropic medications,have been shown to reduce insulin resistance and development of *** conclusion,the above evidence suggests that DNL could be a potential pathological factor associated with various metabolic abnormalities,and a new avenue for translational research and therapeutic drug designing in PDs.

关键词： Psychotropic medications metabolic complications De novo lipogenesis Obesity Diabetes Non-alcoholic fatty liver disease

New soliton solutions of Dual mode sawada Kotera equation using a new form of modified Kudryashov method and the finite difference method

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Journal of Ocean Engineering and science 2024年第3期9卷 207-215页

作者： Khalid K.ali m.s.mehanna Abdel-Haleem Abdel-Aty Abdul-majid Wazwaz Department of mathematics Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt Faculty of Engineering MTI UniversityCairoEgypt Department of Physics College of SciencesUniversity of BishaPO Box 344Bisha 61922Saudi Arabia Physics Department Faculty of ScienceAl-Azhar UniversityAssiut 71524Egypt Department of mathematics Saint Xavier UniversityChicagoIL 60655USA

In this article,we suggest a new form of modified Kudryashov’s method(NmK)to study the Dual-mode sawada Kotera *** know very well that the more the solutions depend on many constants,the easier it is to study the model better by observing the change in the constants and what their impact is on the *** this point of view,we developed the modified Kudryashov method and put it in a general form that contains more than one controllable *** have studied the model in this way and presented figures showing the correctness of what we hoped to reach from the proposed *** addition to the results we reached,they were not sufficient,so we presented an extensive numerical study of this model using the finite differences *** also came up with the local truncation error for the difference scheme is h^(6) k^(2)(1+k^(2)).In addition,the analytical solutions we reached were compared with the numerical solutions,and we presented many forms that show that the results we reached are a clear contribution to this field.

关键词： soliton solution A new form of analytical method Local truncation error Numerical solutions