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First Light Curve Analysis of NSVS 8294044,V1023 Her,and V1397 Her Contact Binary Systems

Research in astronomy and Astrophysics 2024年第5期24卷 1-12页

作者： Atila Poro Sabrina Baudart Mahshid Nourmohammad Zahra Sabaghpour Arani Fatemeh Farhadi Selda Ranjbar Salehian Ahmad Sarostad Saeideh Ranjbaryan Iri Olya Maryam Hadizadeh AmirHossein Khodaei astronomy Department of the Raderon AI Lab. BurnabyBCCanada Double Stars Committee SociétéAstronomique de FranceParisFrance Independent Astrophysics Researcher IsfahanIran Akhtaran Astronomical society Isfahan ProvinceAran and BidgolIran Department of Physics Faculty of ScienceZanjan UniversityZanjanIran astronomy Students'Scientific Association University of TabrizEast Azerbaijan ProvinceTabrizIran Yazd Desert Night Sky astronomy Institute Yazd ProvinceYazdIran Ayaz Astronomical Association East Azerbaijan ProvinceTabrizIran Khayyam astronomy Association FarsFasaIran

The first photometric light curve investigation of the NSVS 8294044,V1023 Her,and V1397 Her binary systems is *** used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite data for V1023 Her and V1397 *** primary and secondary times of minima were extracted from al the data,and,by collecting the literature,a new ephemeris was computed for each *** fits for the O-C diagrams were conducted using the Markov Chain Monte Carlo (MCMC) *** curve solutions were performed using the PHysics Of Eclipsing BinariEs Python code and the MCMC *** systems were found to be contact binary stars based on the fillout factor and mass ratio.V1023 Her showed the O’Connell effect and a cold starspot on the secondary component was required for the light curve *** absolute parameters of the system were estimated based on an empirical relationship between orbital period and *** presented a new T–M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the *** positions of the systems were also depicted on the M–L,M–R,q–L_(ratio),and M_(tot)–J_(0)diagrams in the logarithmic scales.

关键词： (stars:)binaries eclipsing-techniques photometric-stars individual(NSVS 8294044)

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Predicting density log from well log using machine learning techniques and heuristic optimization algorithm:A comparative study

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Petroleum Research 2024年第2期9卷 176-192页

作者： Mehdi Rahmati Ghasem Zargar Abbas Ayatizadeh Tanha National iranian Drilling Company Well Logging DepartmentAhwazIran Faculty member of Petroleum University of Technology Iran Department of Petroleum Engineering Tarbiat Modares UniversityTehranIran

In the petroleum industry,the analysis of petrophysical parameters is critical for efficient reservoir management,production optimization,development strategies,and accurate hydrocarbon reserve *** recent years,the integration of machine learning methodologies has revolutionized the field,addressing challenges in geology,geophysics,and petroleum engineering,even when confronted with limited or imperfect *** study focuses on the prediction of density logs,a pivotal factor in evaluating reservoir hydrocarbon *** is important to note that during well logging operations,log data for specific depths of interest may be missing or incorrect,presenting a significant *** tackle this issue,we employed the Adaptive Neuro-Fuzzy Inference System(ANFIS)and Artificial Neural Networks(ANN)in combination with advanced optimization algorithms,including Particle Swarm Optimization(PSO),Imperialist Competitive Algorithms(ICA),and Genetic Algorithms(GA).These methods exhibit promising performance in predicting density logs from gamma-ray,neutron,sonic,and photoelectric log ***,our results highlight that the Genetic Algorithms-based Artificial Neural Network(GA-ANN)approach outperforms all other methods,achieving an impressive Mean Squared Error(MSE)of *** comparison,ANFIS records an MSE of 0.0015,ICA-ANN 0.0090,PSO-ANN 0.0093,and ANN 0.0183.

关键词： Density log Machine learning approaches Artificial neural networks(ANN) Adaptive neuro-fuzzy inference system(ANFIS) Optimization algorithm

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Two-dimensional Parameter Relationships for W UMa-type Systems Revisited

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Research in astronomy and Astrophysics 2024年第1期24卷 51-58页

作者： Atila Poro Ehsan Paki Ailar Alizadehsabegh Mehdi Khodadadilori Selda Ranjbar Salehian Mahya Hedayatjoo Fatemeh Hashemi Yasaman Dashti Fatemeh Mohammadizadeh astronomy Department of the Raderon AI Lab. BurnabyBCCanada Faculty of Electrical and Computer Engineering Department of PhotonicsUniversity of TabrizTabriz 51664Iran Department of Electrical Engineering Amirkabir University of TechnologyTehranIran astronomy Students'Scientific Association University of TabrizTabriz 51664Iran Department of Physics Iran University of Science and TechnologyTehranIran Institute for the Intellectual Development(Kanoon) Astronomy GroupBojnordIran Department of Mechanical Engineering Amirkabir University of TechnologyTehranIran Aerospace Engineering Department Science and Research Branch of Islamic Azad UniversityTehranIran

Reviewing the empirical and theoretical parameter relationships between various parameters is a good way to understand more about contact binary *** this investigation,two-dimensional(2D)relationships for P–MV(system),P–L1,2,M1,2–L1,2,and q–Lratiowere *** sample used is related to 118 contact binary systems with an orbital period shorter than 0.6 days whose absolute parameters were estimated based on the Gaia Data Release 3 *** reviewed previous studies on 2D relationships and updated six parameter ***,Markov chain Monte Carlo and Machine Learning methods were used,and the outcomes were *** selected 22 contact binary systems from eight previous studies for comparison,which had light curve solutions using spectroscopic *** results show that the systems are in good agreement with the results of this study.

关键词： (stars:)binaries(including multiple):close stars:fundamental parameters methods:data analysis

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On the Relation Between Symmetry of Radio Galaxies and Their Physical Parameters

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Research in astronomy and Astrophysics 2024年第9期24卷 37-59页

作者： Mohsen Javaherian Halime Miraghaei Hooman Moradpour Research Institute for astronomy and Astrophysics of Maragha(RIAAM) University of MaraghehP.O.Box 55136-553MaraghehIran

Gravity as a fundamental force plays a dominant role in the formation and evolution of cosmic objects and leaves its effect in the emergence of symmetric and asymmetric ***,analyzing the symmetry criteria allows us to uncover mechanisms behind the gravity interaction and understand the underlying physical processes that contribute to the formation of large-scale structures such as *** use a segmentation process using intensity thresholding and the k-means clustering algorithm to analyze radio galaxy *** employ a symmetry criterion and explore the relation between morphological symmetry in radio maps and host galaxy *** properties(stellar mass,black hole mass,optical size(R_(50)),concentration,stellar mass surface density(μ_(50)),and stellar age)and radio properties(radio flux density,radio luminosity,and radio size)are *** found that there is a correlation between symmetry and radio size,indicating larger radio sources have smaller symmetry ***,size of radio sources should be considered in any investigation of *** correlations are also observed with other properties,such as R_(50)for FRI galaxies and stellar *** compare the symmetry differences between FRI and FRII radio *** galaxies show higher symmetry in 1.4 GHz and 150 MHz *** the influence of radio source sizes,we discovered that this result is independent of the sizes of radio *** findings contribute to our understanding of the morphological properties and analyses of radio galaxies.

关键词： methods:data analysis techniques:image processing catalogs galaxies:nuclei galaxies:distances and redshifts

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Examining the Effect of Hydroalcoholic Extract of Dracaena cinnabari on Sex Hormones and Ovarian and Uterine Tissues of Rats

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World Journal of Traditional Chinese Medicine 2024年第2期10卷 213-219页

作者： Elham Najafi Bahareh Babaei Hoolari Akbar Karimi Aliasghar Pilehvarian Department of Cellular Biology Genesis Evolution-Develoment Isfahan Payame Noor University IsfahanIran Department of Anatomy School of MedicineTehran University of Medical SciencesTehranIran Department of Biology Group Faculty Member of Isfahan Payame Noor UniversityIsfahanIran

Introduction: Dracaena cinnabari is considered a rich source of phytochemicals used widely in traditional medicine. In the present study, the effect of D. cinnabari hydraulic extract on the reproductive system of female rats was investigated. Methods: The samples were randomly divided into four groups(six samples in each group), including three treatment groups and one control group, and all samples were kept at the same conditions. Hydraulic extract of D. cinnabari and injected intraperitoneally daily for 10 days, while physiological serum was used for injection in to the control group. After 10 days of injection, estrogen and progesterone levels were measured by enzyme immunoassay technique. After dissection, the ovaries and uterine tissues were isolated for histological examination, and tissue changes were carefully examined. Results: The results revealed that the levels of estrogen and progesterone in experimental Groups 2 and 3 had a significant increase(P < 0.001). Regarding tissue changes, a significant increase was observed in epithelial thickness(P < 0.001), number of corpus luteum(P < 0.01), and Graafian follicle(P < 0.01) in doses of 100 and 150 mg/kg. Conclusions: Based on the results, it seems that D. cinnabari extract has an effect on the ovarian follicles.

关键词： Dracaena cinnabari herbal medicine ovarian tissues reproductive sex hormones

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Platform Evolution in an Oligo-Miocene Back-arc Basin:An Example from the Central iran Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 185-206页

作者： Masoud SHARIFI-YAZDI Amirhossein ENAYATI Jamal SALEHI AGHDAM Mohammad BAHREHVAR Seyed Mustafa REZAEI Department of Geology Faculty of Earth SciencesGeography and AstronomyUniversity of Vienna1090 Vienna.Austria Geology and Geophysics Department Tehran Energy Consultants(TEC Co.)TehranIran School of Geology College of ScienceUniversity of TehranTehranIran Department of Geology Tarbiat Modares UniversityTehranIran

The Qom Formation is the most important hydrocarbon reservoir target in Central *** Qom platform developed in a back-arc basin during the Oligo-Miocene due to the closing of the Tethyan *** formation consists of a variety of carbonate and non-carbonate facies deposited on a platform ranging from supratidal to basin.A combination of tectonic and eustatic events led to some lateral and vertical facies variations in the study *** third-order depositional sequences and related surfaces were identified regarding vertical facies changes in the studied sections of this Oligo-Miocene *** to all results and data,this succession was initially deposited during the Chattian upon a distally steepened ramp of siliciclastic-carbonate composition,including the Bouma ***,from the late Chattian to the Aquitanian,the platform changed into a homoclinal carbonate ramp with a gentle *** respect to tectonic activity,this phase was a calm period during the deposition of the Qom ***,a drowned carbonate platform and a rimmed shelf emerged during the Burdigalian,terminated by the continental deposits of the Upper Red *** all geological characteristics,three main tectono-eustatic evolutionary phases have been recognized in the Qom back-arcbasin.

关键词： carbonate ramp depositional facies submarine fan eustasy basement faults back-arc basin

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BSN:Photometric Light Curve Analysis of Two Contact Binary Systems LS Del and V997 Cyg

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Research in astronomy and Astrophysics 2024年第4期24卷 192-213页

作者： Atila Poro Mehmet Tanriver Elham Sarvari Shayan Zavvarei Hossein Azarara Laurent Corp Sabrina Baudart Asma Ababafi Nazanin Kahali Poor Fariba Zare Ahmet Bulut Ahmet Keskin astronomy Department of the Raderon AI Lab. BurnabyBC.Canada Department of astronomy and Space Science Faculty of ScienceErciyes UniversityKayseri TR-38039Turkiye Erciyes University Astronomy and Space Science Observatory Application and Research CenterKayseri TR-38039Turkiye Independent Astrophysics Researcher TehranIran Department of Physics Shahid Beheshti UniversityTehranIran Faculty of Physics Shahid Bahonar University of KermanP.O.Box 76175KermanIran Double Stars Committee SociétéAstronomique de FranceParisFrance Dez Astronomical Association Khouzestan ProvinceDezfulIran Department of Physics Amirkabir University of TechnologyTehranIran Department of Physics Faculty of SciencesCanakkale Onsekiz Mart UniversityTerzioglu KampusuTR-17020CanakkaleTurkiye Astrophysics Research Center and Observatory Canakkale Onsekiz Mart UniversityTerzioğlu KampusuTR-17020CanakkaleTürkiye

The light curve analyses and orbital period variations for two contact binary stars,LS Del and V997 Cyg,are presented in this work which was conducted in the frame of the Binary Systems of South and North project Ground-based photometric observations were performed at two observatories in *** used the Transiting Exoplanet Survey Satellite(TESS)data for extracting times of minima and light curve analysis of the targe *** O-C diagram for both systems displays a parabolic *** Del and V997 Cyg’s orbital periods are increasing at rates of dP/dt=7.20×10^(-08)days yr^(-1)and dP/dt=2.54×10^(-08)days yr^(-1),respectively Therefore,it can be concluded that mass is being transferred from the less massive star to the more massive component with a rate of dM/dt=-1.96×10^(-7)M_(⊙)yr^(-1)for the LS Del system,and dM/dt=-3.83×10^(-7)M_(⊙)yr-1for V997 *** parameters of a third possible object in the system are also *** PHysics Of Eclipsing BinariEs Python code was used to analyze the light *** light curve solutions needed a cold starspot due to the asymmetry in the LS Del system’s light curve *** mass ratio fill-out factor,and star temperature all indicate that both systems are contact binary types in this *** methods were applied to estimate the absolute parameters of the systems:one method relied on the parallax of Gaia DR3,and the other used a P-M *** positions of the systems are also depicted on the M-L,M-R q-L_(ratio),and logM_(tot)-logJ_(0)*** recommend that further observations and investigations be done on the existence of a fourth body in this system.

关键词： (stars:)binaries:eclipsing methods:observational stars:individual(LS Del and V997 Cyg)

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BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-Mu Li Cai-Yan Mao Institute of astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

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Period–Luminosity Relationship forδScuti Stars Revisited

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Research in astronomy and Astrophysics 2024年第2期24卷 138-143页

作者： Atila Poro S.Javad Jafarzadeh Roghaye Harzandjadidi Mohammad Madani Elnaz Bozorgzadeh Esfandiar Jahangiri Ahmad Sarostad Ailar Alizadehsabegh Maryam Hadizadeh Mohammad EsmaeiliVakilabadi The Raderon AI Laboratory Astronomy DepartmentBurnabyBCCanada Department of Physics University of Texas at Dallas800 W.Campbell Rd.RichardsonTX 75080USA Department of Theoretical Physics and Astrophysics University of ZanjanZanjanIran Independent researcher TehranIran Department of Electronics and Telecommunications Politecnico Di TorinoTurinItaly Independent researcher IsfahanIran Yazd Desert Night Sky astronomy Institute YazdIran Department of Photonics Tabriz UniversityTabrizIran Khayyam astronomy Association FarsFasaIran

The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375δScuti stars from the ASAS *** selected stars have a variety of observational characteristics,with a higher than 80%probability of beingδScuti *** have displayed all the stars in the Hertzsprung-Russell diagram along with theδScuti instability strip,the Zero Age Main Sequence and the Terminal Age Main ***,we determined which fundamental and overtone modes each star belongs to using pulsation constant(Q)*** addition,we evaluated the parameters in the Q calculation equation using three machine learning methods,which showed that surface gravity and temperature have the greatest effect on its *** Period-Luminosity(P-L)relationship of theδScuti stars was also ***,using least squares linear regression,we made four linear fits for fundamental and overtone modes and updated their relationships.

关键词： stars variables delta Scuti--stars fundamental parameters-methods data analysis

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BSN:The First Light Curve Analysis of the Total Eclipse Binary System EL Tuc

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Research in astronomy and Astrophysics 2024年第10期24卷 66-75页

作者： Elham Sarvari Eduardo Fernández Lajús Atila Poro Independent researcher TehranIran Instituto de Astrofísica de La Plata(CCT La Plata-CONICET-UNLP) La PlataArgentina BSN Project &Astronomy Department of the Raderon AI Lab.BurnabyBCCanada

We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's *** photometric observations were made using standard multiband BVR_cI_c filters at an observatory in *** presented a new ephemeris for EL Tuc and a linear fit to the O–C diagram,utilizing our extracted times of minima and additional *** employed the PHysics Of Eclipsing BinariEs Python code and the Markov chain Monte Carlo approach for the system's light curve *** target system's light curve solution required a cold starspot on the hotter *** conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172±0.002,an orbital inclination of i=83°.74±0°.40,and a fillout factor of f=53.7%±1.6%.We used the P-a relationship and the Gaia Data Release 3 parallax method to determine the absolute parameters of EL Tuc to compare the precision of our *** system was classified as W-type based on the mass and effective temperature of the companion *** positions of the systems were depicted on the M-L,M-R,T-M,and *** relationship between the spectroscopic and photometric mass ratios of binaries was discussed.

关键词： (stars:)binaries:eclipsing stars:individual(EL Tuc) line:identification

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