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The mathematical weighting of GNSS observations based on different types of receivers/antennas and environmental conditions

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Geodesy and Geodynamics 2023年第5期14卷 521-540页

作者： Kamal Parvazi saeed farzaneh Abdolreza Safari School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranNorth Kargar Street***TehranIran

Stochastic models play an important role in achieving high accuracy in positioning,the ideal estimator in the least-squares(LS)can be obtained only by using the suitable stochastic *** study investigates the role of variance component estimation(VCE)in the LS method for Precise Point Positioning(PPP).This estimation is performed by considering the ionospheric-free(IF)functional model for code and the phase observation of Global Positioning System(GPS).The strategy for estimating the accuracy of these observations was evaluated to check the effect of the stochastic model in four modes:a)antenna type,b)receiver type,c)the tropospheric effect,and d)the ionosphere *** results show that using empirical variance for code and phase observations in some cases caused erroneous estimation of unknown components in the PPP *** is because a constant empirical variance may not be suitable for various receivers and antennas under different *** were compared in two cases using the stochastic model of nominal weight and weight estimated by *** position error difference for the east-west,north-south,and height components was 1.5 cm,4 mm,and 1.8 cm,***,weight estimation with LS-VCE can provide more appropriate ***,the convergence time based on four elevation-dependent models was evaluated using nominal weight and LS-VCE *** to the results,the LS-VCE has a higher convergence rate than the nominal *** weight estimation using LS-VCE improves the convergence time in four elevation-dependent models by 11,13,12,and 9 min,respectively.

关键词： Stochastic model Global positioning system Variance component estimation Least-squares Precise point positioning Elevation-dependent model

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Modeling viscosity of methane,nitrogen,and hydrocarbon gas mixtures at ultra-high pressures and temperatures using group method of data handling and gene expression programming techniques

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Chinese Journal of Chemical Engineering 2021年第4期34卷 431-445页

作者： farzaneh Rezaei saeed Jafari Abdolhossein Hemmati-Sarapardeh Amir H.Mohammadi Department of Petroleum Engineering Shahid Bahonar University of KermanKermanIran Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam Faculty of Environment and Chemical Engineering Duy Tan UniversityDa Nang 550000Vietnam Institut de Recherche en Genie Chimique et Petrolier(IRGCP) Paris CedexFrance Discipline of Chemical Engineering School of EngineeringUniversity of KwaZulu-NatalHoward College CampusKing George V AvenueDurban 4041South Africa

Accurate gas viscosity determination is an important issue in the oil and gas *** approaches for gas viscosity measurement are timeconsuming,expensive and hardly possible at high pressures and high temperatures(HPHT).In this study,a number of correlations were developed to estimate gas viscosity by the use of group method of data handling(GMDH)type neural network and gene expression programming(GEP)techniques using a large data set containing more than 3000 experimental data points for methane,nitrogen,and hydrocarbon gas *** is worth mentioning that unlike many of viscosity correlations,the proposed ones in this study could compute gas viscosity at pressures ranging between 34 and 172 MPa and temperatures between 310 and 1300 ***,a comparison was performed between the results of these established models and the results of ten wellknown models reported in the *** absolute relative errors of GMDH models were obtained 4.23%,0.64%,and 0.61%for hydrocarbon gas mixtures,methane,and nitrogen,*** addition,graphical analyses indicate that the GMDH can predict gas viscosity with higher accuracy than GEP at HPHT ***,using leverage technique,valid,suspected and outlier data points were ***,trends of gas viscosity models at different conditions were evaluated.

关键词： Gas Viscosity High pressure high temperature Group method of data handling Gene expression programming

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Conceptual Method of Temperature Sensation in Bionic Hand by Extraordinary Perceptual Phenomenon

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Journal of Bionic Engineering 2021年第6期18卷 1344-1357页

作者： saeed Bahrami Moqadam Ahamd Saleh Asheghabadi farzaneh Norouzi Hamed Jafarzadeh Ali Khosroabadi AfshinAlagheband Ghazal Bangash Negar Morovatdar Jing Xu State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing100084China Medical University of Mashhad 13131–99137MashhadIran Center for Computational and Data Intensive Science and Engineering(CDISE) Skolkovo Institute of Science and Technology(Skoltech)Moscow121205Russia Department of Mechanical Engineering Ferdowsi UniversityMashhad***Iran Department of Electrical Engineering Ferdowsi UniversityMashhad***Iran Department of Computer Engineering Ferdowsi UniversityMashhad***Iran Clinical Research Unit Imam Reza HospitalMashhad University of Medical Sciences13131–99137MashhadIran

Lack of temperature sensation of myoelectric prosthetic hand limits the daily activities of *** this end,a noninvasive temperature sensation method is proposed to train amputees to sense temperature with psychophysical sensory *** this study,22 healthy participants took part besides 5 amputee *** duration time of the study was 31 days with five test steps according to the Leitner *** adjustable temperature mug and a Peltier were used to change the temperature of the water/phantom digits to induce temperature to ***,to isolate the surroundings and show colors,a Virtual Reality(VR)glass was *** statistical results conducted are based on the response of participants with questionnaire *** Chi-square tests,it is concluded that participants answer the experiment significantly correctly using the Leitner technique(P value<0.05).Also,by applying the“Repeated Measures ANOVA”,it is noticed that the time of numbness felt by participants had significant(P value<0.001)*** could remember lowest and highest temperatures significantly better than other temperatures(P value<0.001);furthermore,the well-trained amputee participant practically using the prosthesis with 72.58%could identify object’s temperature with only once time experimenting the color temperature.

关键词： Temperature perceptions Leitner learning technique Classical conditioning Psychophysical sensory substitution Extraordinary perceptual phenomenon Bionic hand prosthesis

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Transradial angiography procedure approach in with and without radial artery anomalies

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Health 2013年第6期5卷 1079-1084页

作者： saeed Yazdankhah Ahmadreza Assareh Shahla Majeedi Mehdi Easapour Mohammad Nourizadeh farzaneh Ahmadi Farzad Daeinejad Cardiovascular Disease Research Center Joundishapour University Ahvaz Iran Cardiovascular Disease Research Center Joundishapour University Ahvaz Iran

Introduction: The transradial coronary angiography has several benefits such as the reducetion in access site complications especially in fully anticoagulated patients. The presence of arterial anomalies in upper limb arteries has an important role in procedural success. Methods: retrograde transarterial sheath injection was done in patients with transradial coronary angiography. Arterial anomalies in the upper limb evaluated. Cannulation time, the time of catheter passage to ascending aorta, and Angiographic time, were also meseared. Results: in 2011, 165 consecutive patients were studied, 116 (70.3%) male, age 56.7 ± 11.1 years. With 96.6% success rate in procedure, totally 59 anomolies were observed in 44 patients (26.7%). Radial artery by itself had ?25 anomalies (15.1%). The most frequent anomaly was abnormal origin of radial artery in 14 patients (8.5%) followed by tortuosities in 10 ulnar (6%). 9 brachial (5.4%), 7 radial (4/2%), 5 subclavian (3%) and 3 brachiocephalic arteries (1.8%). There also were 4 loops in ulnar artery (2.4%) and one in radial and brachinl arteries (each 0.6%). Other anomalies include 4 patients (2.4%), except cannulation time (p = 0.97), there were associations between anomalies and each of other times (p = 0.001) and contrast volume (p = 0.009). Anomalies didn’t have any effect on procedural success rate and just in one patient with sulclavian loop procedure changed to femoral approach (p = 0.19).

关键词： Transradial Angiography Radial Anomalies

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