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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

Development of seismic fragility curves for precast concrete frames with cast-in-situ concrete shear-walls

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 149-167页

作者： Aliakbar Yahyaabadi Roozbeh Talebkhah Mahdi Adibi Faculty of Engineering University of BojnordBojnord 94531-55111Iran

Precast reinforced concrete buildings have been well received in some seismic zones worldwide due to advantages such as the ease and the speed of implementation,and the possibility of working in inappropriate atmospheric *** this research,seismic fragility curves were developed for precast concrete frames with a cast-in-situ concrete shear-wall,concerning the important issues of modeling the precast beam-column joints,construction quality,and soil type *** this purpose,the incremental dynamic analysis(IDA)was conducted for three-dimensional models of 3-,5-,and 8-story buildings under two record sets corresponding to soil types C and D of the NEHRP ***-column joints were modeled using nonlinear rotational springs with rigid links with respect to the finite size of the joint *** demonstrate that the Weibull distribution can be fitted to the damage state capacities better than the lognormal distribution at the intensities that are more than one standard deviation away from the median damage *** seismic vulnerability of precast structures increases at all damage states as the height of the building *** is also observed that soil type has almost no considerable effect on the fragility curve parameters for all damage states considered herein.

关键词： fragility curve incremental dynamic analysis precast beam-column joints construction quality soil type effects

Assessing and Improving General English university Students＇ Main Sub-skills of Reading Compression： A Case of university of bojnord

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Sino-US English Teaching 2016年第4期13卷 245-260页

作者： Majid Elahi Shirvan university ofbojnord Bojnord Iran

General English course at Iranian universities has always been a controversial issue since the students taking this course are rather weak in English proficiency and need more authentic instructions based on accurate need analysis. The materials applied in this course are mainly focused on reading comprehension. Thus, the purpose of the present study was to improve General English university students＇ main sub-skills of reading comprehension and see the effect of the possible changes in terms of time and the fields of study of the students. To do this, 168 university students taking General English course at university of bojnord, including humanities, engineering, physical education, and sciences, received instruction on the main sub-skills of reading comprehension after taking a pre-test sample TOELF section of reading comprehension. After 16 sessions of 90 minute instruction, they took the post-test section of TOEFL sample of reading comprehension. Mixed between within subject analysis of variance was used to assess the impact of instruction for the four groups of students from pre-test to post-test. The findings of the study indicated that the effect of instruction in terms of time, from pre-test to post-test, and the interaction of time and fields of study were significant. Besides, changes for 10 sub-skills were the same among the four fields of study.

关键词： General English reading comprehension skills

Static properties and semileptonic transitions of lowest-lying doubleheavy baryons

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Chinese Physics C 2023年第3期47卷 57-66页

作者： Zahra Ghalenovi Masoumeh Moazzen Sorkhi Department of Physics Kosar University of BojnordIran

The static properties and semileptonic decays of ground-state doubly heavy baryons are studied in the framework of a non-relativistic quark *** a phenomenological potential model,we calculate the ground-state masses and magnetic moments of doubly heavy Ω and Ξ *** the heavy quark limit,we introduce a simple form of the universal Isgur-Wise function used as the transition form factor and then investigate the exclusive b→c semileptonic decay widths and branching fractions for 1/2→1/2 baryon *** obtained results are in agreement with other theoretical predictions.

关键词： hypercentral quark model double heavy baryons semileptonic decay

Experimental investigation and adaptive neural fuzzy inference system prediction of copper recovery from flotation tailings by acid leaching in a batch agitated tank

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 538-546页

作者： Jalil Pazhoohan Hossein Beiki Morteza EsfANDyari Department of Chemical Engineering Quchan University of Technology Department of chemical engineering University of Bojnord

The potential of copper recovery from flotation tailings was experimentally investigated using a laboratory-mixing tank. The experiments were performed with solid weight percentages of 30 wt%, 35 wt%, 40 wt% and 45 wt% in water. The measurements revealed that adding sulfuric acid all at once to the tank rapidly increased the efficiency of the leaching process, which was attributed to the rapid change in the acid concentration. The rate of iron dissolution from tailings was less than when the acid was added gradually. The sample with 40 wt% solid is recommended as an appropriate feed for the recovery of copper. The adaptive neural fuzzy system(ANFIS) was also used to predict the copper recovery from flotation tailings. The back-propagation algorithm and least squares method were applied for the training of ANFIS. The validation data was also applied to evaluate the performance of these models. Simulation results revealed that the testing results from these models were in good agreement with the experimental data.

关键词： flotation tailings leaching copper environments adaptive neural fuzzy inference system

AN EFFICIENT PARALLEL PROCESSING OPTIMAL CONTROL SCHEME FOR A CLASS OF NONLINEAR COMPOSITE SYSTEMS

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Acta Mathematica Scientia 2017年第3期37卷 703-721页

作者： A. JAJARMT M. HAJIPOUR Department of Electrical Engineering University of Bojnord P.O. Box 94531-1339 Bojnord Iran Department of Mathematics Faculty of Basic Sciences Sahand University of Technology P.O. Box 51335-1996 Tabriz Iran

This article presents an efficient parallel processing approach for solving the opti- mal control problem of nonlinear composite systems. In this approach, the original high-order coupled nonlinear two-point boundary value problem （TPBVP） derived from the Pontrya- gin＇s maximum principle is first transformed into a sequence of lower-order deeoupled linear time-invariant TPBVPs. Then, an optimal control law which consists of both feedback and forward terms is achieved by using the modal series method for the derived sequence. The feedback term specified by local states of each subsystem is determined by solving a ma- trix Riccati differential equation. The forward term for each subsystem derived from its local information is an infinite sum of adjoint vectors. The convergence analysis and parallel processing capability of the proposed approach are also provided. To achieve an accurate feedforward-feedbaek suboptimal control, we apply a fast iterative algorithm with low com- putational effort. Finally, some comparative results are included to illustrate the effectiveness of the proposed approach.

关键词： Modal series method nonlinear composite system optimal control parallelprocessing

Correlating thermal conductivity of pure hydrocarbons and aromatics via perceptron artificial neural network (PANN) method

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Chinese Journal of Chemical Engineering 2017年第5期25卷 547-554页

作者： Mostafa Lashkarbolooki Ali Zeinolabedini Hezave Mahdi Bayat School of Chemical Engineering Babol University of Technology Islamic Azad university Dashtestan Branch Department of Chemical Engineering Faculty of EngineeringUniversity of Bojnord

Accurate estimation of liquid thermal conductivity is highly necessary to appropriately design equipments in different industries. Respect to this necessity, in the current investigation a feed-forward artificial neural network(ANN) model is examined to correlate the liquid thermal conductivity of normal and aromatic hydrocarbons at the temperatures range of 257–338 K and atmospheric pressure. For this purpose, 956 experimental thermal conductivities for normal and aromatic hydrocarbons are collected from different previously published *** the modeling stage, to discriminate different substances, critical temperature(Tc), critical pressure(Pc)and acentric factor(ω) are utilized as the network inputs besides the temperature. During the examination, effects of different transfer functions and number of neurons in hidden layer are investigated to find the optimum network architecture. Besides, statistical error analysis considering the results obtained from available correlations and group contribution methods and proposed neural network is performed to reliably check the feasibility and accuracy of the proposed method. Respect to the obtained results, it can be concluded that the proposed neural network consisted of three layers namely, input, hidden and output layers with 22 neurons in hidden layer was the optimum ANN model. Generally, the proposed model enables to correlate the thermal conductivity of normal and aromatic hydrocarbons with absolute average relative deviation percent(AARD), mean square error(MSE), and correlation coefficient(R^2) of lower than 0.2%, 1.05 × 10^(-7) and 0.9994, respectively.

关键词： Thermal conductivity Artificial neural network Critical properties Hydrocarbons Aromatics

Analyzing Culture of Learning and Teaching in the Iranian Secondary Schools English Language Course Books： Prospect

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Sino-US English Teaching 2016年第2期13卷 77-97页

作者： Majid Elahi Shirvan Sajjad Ghadamyari Farhad Ghiasvand Maryam Heydari Fatemeh Azizi university of bojnord Bojnord Iran

Knowing and analyzing the ＂culture of learning and teaching＂ in a coursebook or series of course books can contribute to teachers＇ and students＇ success in the educational and pedagogical goals and objectives. Cultures of learning and teaching refer to the perspectives of teachers and learners towards learning and teaching. Most of the research studies conducted in this field have referred to values and attitudes related to good learning and teaching as reflected through observations, interviews and questionnaires. However, just few studies have examined this term with regard to language teaching materials, and course books. Thus, the purpose of the present study was to introduce, investigate, and analyze the cultures of learning and teaching in Iranian secondary school course books entitled Prospect series. Based on the model used in this study, the cultures of learning and teaching in Prospect series were investigated as reflected in their external features including aims and objectives cited in the introduction, tables of content, and layout of the students＇ books, and internal features including task instructions and visual images in students＇ book plus the instructions in the teacher＇s book. Each of these features as well as the pedagogical issues of the Prospect series were provided and elaborated.

关键词： culture of learning culture of teaching Prospect series pedagogic issues

Planar System-Masses in an Equilateral Triangle:Numerical Study within Fractional Calculus

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 953-968页

作者： Dumitru Baleanu Behzad Ghanbari Jihad H.Asad Amin Jajarmi Hassan Mohammadi Pirouz Department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara06530Turkey Institute of Space Sciences Bucharest76900Romania Department of Engineering Science Kermanshah University of TechnologyKermanshahIran Department of Physics College of Arts and SciencesPalestine Technical UniversityTulkarmPalestine Department of Electrical Engineering University of BojnordBojnordIran

In this work,a system of three masses on the vertices of equilateral triangle is *** system is known in the literature as a planar *** first give a description to the system by constructing its classical ***,the classical Euler-Lagrange equations(i.e.,the classical equations of motion)are ***,we fractionalize the classical Lagrangian of the system,and as a result,we obtain the fractional Euler-Lagrange *** the final step,we give the numerical simulations of the fractional model,a new model which is based on Caputo fractional derivative.

关键词： Planar system masses in equilateral triangle springs Euler-Lagrange equations fractional derivative