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High Voltage 2017年第3期2卷 200-204页

作者： Anton V.Vykhodtsev behzad kordi.derek r.oliver Department of Electrical and Computer Engineering University of Manitoba75a Chancellor's CircleWinnipegManitobaCanada R3T 5V62 Manitoba Institute for Materials University of Manitoba25 Sifton RoadWinnipegManitobaCanada R3T 2N2

Ascertaining the dielectric character of polymeric insulation materials is of particular interest for comparative studies that use accelerated ageing and samples from decommissioned *** the case of polymeric samples,the possibility of physical deformation within the sample holder adds additional variability to comparative *** readily obtainable instrumentation,this study undertakes a systematic sensitivity analysis of a parallel-plate capacitance measurement approach for polymeric materials that only has one capacitance plate in contact with the sample,avoiding issues of sample *** analysis demonstrates that the biggest contributor of uncertainty in the measurement of the relative permittivity and loss tangent is the precision with which the plate–plate and plate–sample separation is *** measurements show that the determination of loss tangent can be susceptible to uncertainties arising from electrical noise,but that these can be controlled further by utilising more refined instrumentation.

关键词： deformation plate analysis

Development of bismuth-based solutions for well plugging and abandonment:A review

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Petroleum research 2024年第2期9卷 250-264页

作者： Lewaa Hmadeh Marcelo Anunciação Jaculli behzad Elahifar Sigbjørn Sangesland Norwegian University of Science and Technology PTSValgrindaS.P.Andersens veg 15 ANorway

Plugging and abandonment(P&A)is a crucial step of the well life *** of how long one stretches the productive life of a well,P&A operations will have to be carried out *** current panorama of our industry includes many wells to be plugged and abandoned,with steep requirements to abide by both regulations and societal *** this context,we must guarantee that no leakage occurs with an eternal perspective in *** has been the prime material for this task,but recent studies have indicated the potential of degradation over time-especially in corrosive environments-and the creation of leaking paths due to its *** has opened up a path toward the usage of alternative *** of the emerging candidates is bismuth,a metal with the unique characteristic of expanding when *** a trait could improve the overall sealability of wellbores and especially during P&*** article discusses the current status of bismuth sealing technologies,introducing the basics of bismuth,the ongoing efforts to qualify it as a barrier material,its potential applications,and the challenges that still need to be *** latest research indicates promising results in terms of its usage as a barrier element.

关键词： Bismuth plugs Bismuth-tin alloys Well plugging and abandonment Well integrity

Cancerous cell viability affected by synergism between electric pulses and a low dose of silver nanoparticle:An adaptive neuro-fuzzy inference system

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Medicine in Novel Technology and Devices 2024年第1期21卷 45-52页

作者： Salim Mirshahi behzad Vahedi Kiarash Aryana Ameneh Sazgarnia Department of Mechanical Engineering Sharif University of TechnologyTehranIran Medical Physics research Center Mashhad University of Medical SciencesMashhadIran Functional Neurosurgery research Center Shohada Tajrish Comprehensive Neurosurgical Center of ExcellenceShahid Beheshti University of Medical SciencesTehranIran Department of Mechanical Engineering Ferdowsi University of MashhadMashhadIran

In the current study,applying simultaneously electroporation and silver nanoparticles(SNPs)are ***,one restriction normally assigned to such nanoparticles is their side effects on the vital organs of the *** mitigate such deleterious effects,it is better to use lower dosages of ***,this can result in a decline in the technique's *** compensate for the lower dose of SNPs,one can use secondary method like electroporation to deliver SNPs directly into the cells and reinforces the effect of electric pulses due to the high electrical conductivity of SNPs while having a minimal cytotoxicity effect on normal cells that are not treated with *** the present study,synergism effects of both procedures(SNPs and electroporation)experimentally and theoretically are considered to investigate the property of each technique in increasing the performance with respect to both procedures'*** investigate more,adaptive neuro-fuzzy inference system(ANFIS)is used to predict the percent cell viability of cancerous cells affected by both procedures by considering amplitude and duration as inputs affecting on change of cell viability as an *** results obtained from both experimental and simulation procedures showed that the maximum synergism between nanoparticles and electric pulses was recorded at 700V/cm strength and 100μs ***,results indicated high correlation between observed and predicted data(r2=0.88).Moreover,the calculated root mean square error for the results of the ANFIS model was equal to *** implies that the model has practical value and can estimate the percent cell viability of cancerous cells influenced by both procedures with varying electric field amplitude and *** method can be proposed for other biophysical or drug delivery applications to save time and resources by utilizing the previous experimental data rather than performing more experiments.

关键词： Electroporation Cancer cell Adaptive neuro-fuzzy inference system Nanoparticle Drug delivery

Towards automated statistical partial discharge source classification using pattern recognition techniques

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High Voltage 2018年第3期3卷 162-169页

作者： Hamed Janani behzad kordi Department of Electrical and Computer Engineering University of Manitoba75A Chancellor's CircleWinnipegMBCanadaR3T5V6 Powertech Labs Inc. 12388-88 AvenueSurreyBCCanadaV3W 7R7

This study presents a comprehensive review of the automated classification in partial discharge(PD)source identification and probabilistic interpretation of the classification results based on the relationship between the variation of the phase-resolved PD(PrPD)patterns and the source of the *** proposed automated classification system consists of modern,high-performance statistical feature extraction methods and classifier *** application in online monitoring and recognition of the PD patterns is investigated based on their low-processing time and high-performance *** application of modern statistical algorithms and pre-processing methods configured in this automated classification system improves the pattern recognition accuracy of the different PD sources that are suitable to be employed in different high-voltage(HV)insulation *** evaluate the performance of the different combinations of the feature extraction/classier pairs,laboratory setups are designed and built that simulate various types of *** test cells include three sources of PD in SF6,two sources of PD in transformer oil,and corona in the *** samples for different classes of PD sources are captured under two levels of voltage and two different levels of *** results of this study evaluate the suitability of the proposed classification systems for probabilistic source identification in various insulation ***,of importance to the problem of the PD source identification is to assign a‘degree of membership’to each PrPD pattern,besides assigning a class label to *** of the classifier algorithms studied in this study,such as fuzzy classifiers,are not only able to show high classification accuracy rate,but they also calculate the‘degree of membership’of a sample to a class of *** enables probabilistic interpretation of a new PrPD pattern that is being *** determination of the degree of membership for future PrPD samples allows saf

关键词： pattern membership source

New experimental study on the DC flashover voltage of polymer insulators:combined effect of surface charges and air humidity

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High Voltage 2019年第4期4卷 316-323页

作者： Mohammed Amer Jeff Laninga William McDermid David r.Swatek behzad kordi Department of Electrical and Computer Engineering University of Manitoba75 Chancellor's CircleWinnipegManitobaCanada R3T 5V6 Manitoba Hydro WinnipegManitobaCanada R3M 3T1

This research provides conclusions that can partially cover the lack of knowledge related to the effects of ambient atmospheric conditions on DC electric power *** polymer insulating materials are used for completing this research *** a climate chamber,the relative humidity is controlled and adjusted from 20%to 80%***,the samples are charged with positive or negative charges by applying±20 kV to the corona-generating ring of *** surface potential is measured using an electrostatic voltmeter and is converted into surface charge density later by applying the probe response matrix *** pre-charged samples are then stressed with high-voltage negative or positive DC values inside the climate chamber over a range of controlled values of the surrounding air humidity until flashover takes *** space charges,which can drift in the air gap to reach the solid surface,are highly affected by the level of the relative humidity of the surrounding ***,increasing humidity results in a reduction of the DC flashover inception voltage and a shorter time to flashover regardless of the voltage ***,the positive or negative flashover inception voltage of both materials increases with pre-deposited negative charges while it decreases with pre-deposited positive charges.

关键词： charges flash humidity

裂纹和污秽瓷绝缘子的电磁场辐射信号特征(英文)

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高电压技术 2011年第11期37卷 2649-2654页

作者： Ehsan Azordegan David r Swatek behzad kordi Department of Electrical and Computer Engineering University of ManitobaWinnipegMBCanada Insulation Engineering and Testing Department Manitoba HydroWinnipegMBCanada

Porcelain cap and pin insulators are by far the most popular suspension insulators in high voltage(HV) distribution networks all around the *** and condition monitoring of HV insulators is also very important to the utility companies because of the critical and vital role that they play in distribution *** terms of safety, practicality and ease of use,remote detection methods are more popular among the line technicians.A new remote condition assessment method based on electromagnetic radiations from porcelain insulators is presented in this paper. In a lab environment,a string of two porcelain insulators is energized by a 45 kV *** radiations due to the partial discharge activities inside the porcelain insulator are captured by passive sensors and antennas. Two cases of defective insulators on a two insulator string are studied *** first case focuses on the effect of contaminated porcelain shells on radiation signature of partial discharges.A polluted porcelain shell with ESDD level of 0.03 mg/cm^2 was first *** second case studies the effect of cracks of an intentionally-cracked porcelain shell. The cracked insulator is also tested on a two insulator *** compare the partial discharge radiation signature of different faulty insulators,phase resolved graphs were *** electromagnetic radiated signature of a polluted insulator and a cracked insulator was calculated and compared using phase resolved graphs.

关键词： partial discharge electromagnetic radiation contamination high voltage porcelain insulator condition assessment phase resolved graph

Guest Editorial: Automated Partial Discharge Measurement, Analysis, and Interpretation

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High Voltage 2018年第3期3卷 161-161页

作者： kordi, behzad Univ Manitoba Dept Elect & Comp Engn McMath High Voltage Lab Mcmathhvlab Ca Winnipeg MB R3T 5V6 Canada

This Special Section of High Voltage is comprised of one invited review,one review article and two research papers that are related to partial discharge(PD)measurement,analysis and *** invited review paper entitled‘Towards automated statistical partial discharge source classification using pattern recognition techniques’by *** et *** a comprehensive study of automated classification in partial discharge source identification,and probabilistic interpretation of classification results based on the relationship between the variation of phase resolved partial discharge(PrPD)patterns and the source of partial *** application of an enhanced automated classification system on different sources of PD in different high-voltage insulation media is also investigated.

关键词： PrPD insulation probabilistic

Evaluation of surface roughness and optimization of cutting parameters in turning of AA2024 alloy under different cooling-lubrication conditions using rSM method

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Journal of Central South University 2020年第6期27卷 1714-1728页

作者： Seyed Hasan MUSAVI Behnam DAVOODI behzad ESKANDArI Department of Mechanical Engineering Amirkabir University of TechnologyTehran 15875-4413Iran School of Mechanical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran Department of Mechanical Automotiveand Materials EngineeringUniversity of WindsorWindsorCanada

In the present study,the effect of reduction of cutting fluid consumption on the surface quality and tool wear was *** models were developed to predict the surface roughness using response surface methodology(rSM).Analysis of variance(ANOVA)was used to investigate the significance of the developed regression *** results showed that the coefficient of determination values(r^2)for the developed models was 97.46%for dry,89.32%for flood mode(FM),and 99.44%for MQL,showing the high accuracy of fitted ***,under the minimum quantity lubrication(MQL)condition,the surface roughness improved by 23%−44%and 19%−41%compared with dry and FM,respectively,and the SEM images of machined surface proved the *** prepared SEM images of tool rake face also showed a considerable decrease in adhesion ***-up edge and built-up layer were the two main products of the adhesion wear,and energy-dispersive X-ray spectroscopy(EDX)analysis of specific points on the tool faces helped to discover the chemical compositions of adhered *** changing dry and FM to MQL mode,dominant mechanism of tool wear in machining aluminum alloy was significantly *** wear that led to early failure of cutting edge was also controlled by MQL technique.

关键词： cooling-lubrication methods surface roughness minimum quantity lubrication response surface methodology AA2024 aluminum alloy

Estimation of froth flotation recovery and collision probability based on operational parameters using an artificial neural network

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 526-534页

作者： Saeed Chehreh Chelgani behzad Shahbazi Bahram rezai Surface Science Western Research Park University of Western Ontario Mining Engineering Department Science and Research Branch Islamic Azad University Amirkabir University of Technology

An artificial neural network and regression procedures were used to predict the recovery and collision probability of quartz flotation concentrate in different operational conditions. Flotation parameters, such as dimensionless numbers （Froude, reynolds, and Weber）, particle size, air flow rate, bubble diameter, and bubble rise velocity, were used as inputs to both methods. The linear regression method shows that the relationships between flotation parameters and the recovery and collision probability of flotation can achieve correlation coefficients （r2） of 0.54 and 0.87, respectively. A feed-forward artificial neural network with 3-3-3-2 arrangement is able to simultaneously estimate the recovery and collision probability as the outputs. In testing stages, the quite satisfactory correlation coefficient of 0.98 was achieved for both outputs. It shows that the proposed neural network models can be used to determine the most advantageous operational conditions for the expected recovery and collision probability in the froth flotation process.

关键词： flotation recovery collision probability neural networks

Predicting chemical speciation of metals in soil using Visual Minteq

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Soil Ecology Letters 2023年第3期5卷 53-60页

作者： Sana Khalid Muhammad Shahid Zeid A.ALOthman Abdullah A.Al-Kahtani behzad Murtaza Camille Dumat Department of Environmental Sciences COMSATS University IslamabadVehari 61100Pakistan Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia DYNAFOr INrAE&Toulouse INP France CErTOP CNrS-UT2J-UPS France

From soil contamination and risk assessment perspectives,it is imperative to understand the ecological processes occurring in *** soil processes greatly affect chemical speciation of potentially toxic metals(PTMs),and thus also influence their biogeochemical *** current study analyzed chemical speciation of eight PTMs(Cd,Cr,Fe,Cu,Mn,Ni,Zn,and Pb)in upper and lower soil layers for 15 agronomic fields of Vehari-Pakistan using Visual Minteq *** divalent forms of most PTMs(PTM^(2+))generally predominated in both soil layers(79.9%overall occurrence).However,chromium revealed a different pattern of chemical speciation(95.8%as CrOH^(+))compared to other *** mean percentage of all the PTMs2+was slightly higher for the lower soil layer(81.3%)than in the upper layer(78.4%),the trend being same for all the PTMs,except *** higher PTMs^(2+)percentage in lower soil layers than upper layers was due to lower content of organic matter and other anions such as Cl^(−)and HCO_(3)_(−).The mean percentage ages of all the PTMs^(2+)was similar among all the 15 agronomic fields,which was confirmed by strong Pearson correlation values(r^(2)>0.95).The PCA graph grouped all the agronomic fields and PTM^(2+) closely,except Cr^(2+) and Cu^(2+).This grouping confirmed the similar chemical speciation of PTMs,except Cu and Cr in studied fields.

关键词： heavy metals free ionic forms agricultural soils multivariate analysis PCA