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Journal of Ocean University of China 2020年第4期19卷 772-780页

作者： KURT ali TOZAR ali TASBOZAN Orkun Department of Mathematics Faculty of Science and ArtPamukkale UniversityDenizli 20160Türkiye Department of Physic Faculty of Science and ArtMustafa Kemal UniversityHatay 31001Türkiye Department of Mathematics Faculty of Science and ArtMustafa Kemal UniversityHatay 31001Türkiye

In this study,the potential Kadomtsev-Petviashvili(pKP)equation,which describes the oblique interaction of surface waves in shallow waters,is solved by the new extended direct algebraic *** results of the study show that by applying the new direct algebraic method to the pKP equation,the behavior of the obliquely interacting surface waves in two dimensions can be *** article fairly clarifies the behaviors of surface waves in shallow *** the literature,several mathematical models have been developed in attempt to study these behaviors,with nonlinear mathematics being one of the most important steps;however,the investigations are still at a level that can be called‘baby steps’.Therefore,every study to be carried out in this context is of great ***,this study will serve as a reference to guide scientists working in this field.

关键词： conformable fractional derivative new extended direct algebraic method interacting wave equation shallow water waves

Numerical analysis of reactive turbulent flow in the thrust chamber of RD-108 engine rocket

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Defence Technology（防务技术） 2019年第4期15卷 565-575页

作者： Seyed Reza Taghavi Mohammad ali Dehnavi ali Ghafouri Department of Chemical Engineering Imam Hossein Comprehensive University

Combustion chamber modeling and simulation of the liquid propellant engine with kerosene as fuel and liquid oxygen as an oxidizer in the turbulent flow field are performed by CFD *** flow is modeled as Single-phase in steady state and using RNG k-ε turbulence *** results are validated by experimental data of thrust,special impulse and combustion chamber *** comparing t.^wo reaction models of finite rate chemistry and frozen model with experimental data,it is concluded that finite rate chemistry has acceptable *** optimum value of equivalence ratio(oxidizer to fuel ratio)per reaction and operational parameters of the engine which maximize thrust and special impulse are determined.

关键词： Liquid propellant engine Computational fluid dynamics(CFD) Kerosene and oxygen Freeze model Finite rate chemistry model

A discrete element model for simulating saturated granular soil

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Particuology 2011年第6期9卷 650-658页

作者： ali Asghar Mirghasemi School of Civil Engineering College of Engineering University of Tehran

A numerical model is developed to simulate saturated granular soil, based on the discrete element method. Soil particles are represented by Lagrangian discrete elements, and pore fluid, by appropriate discrete elements which represent alternately Lagrangian mass of water and Eulerian volume of space. Macroscale behavior of the model is verified by simulating undrained biaxial compression tests. Micro-scale behavior is compared to previous literature through pore pressure pattern visualization during shear tests. It is demonstrated that dynamic pore pressure patterns are generated by superposed stress waves. These pore-pressure patterns travel much faster than average drainage rate of the pore fluid and may initiate soil fabric change, ultimately leading to liquefaction in loose sands. Thus, this work demonstrates a tool to roughly link dvnamic stress wave patterns to initiation of liQuefaction nhenomena.

关键词： Discrete element method Granular soil Saturated soil Pore pressure

Recent progresses in dry gas polymeric filters

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Journal of Energy Chemistry 2021年第11期30卷 103-119,I0003页

作者： Samaneh Bandeh ali Hamid Ghasemi Reyhaneh Ahmadi ali Ghaffari Department of Chemical Engineering Faculty of EngineeringArak UniversityArak 38156-8-8349Iran Department of Mechanical Engineering Arak University of TechnologyArak38181-41167Iran Department of Mechanical Engineering Iran University of Science and TechnologyTehranIran

Filtration and membrane separation are popular methods in gas separation since they are cost and energy efficient. Despite to air filters, there are comparatively few studies on dry gas filters, particularly at industrial scale. In fact, major unsolved challenges such as high efficiency, low pressure drop, long-term stability, high-thermal and chemical stability and advanced physiochemical properties, are still remained. The aim of this review is to scrutinize the advanced scientific and technological practices (such as selection of appropriate polymeric materials and additives, nanotechnology, modification techniques and preparation methods) towards design and fabrication of an efficient filter media for solid particles removal from the natural gas flow. Recent progresses in solid particle separation mechanisms, modeling and simulation techniques and the effect of membrane fabrication methods on its performance, strategies for modification of filter media, current challenges and future perspective are discussed.

关键词： Filtration Solid particle separation Dry gas filter Membrane Nanotechnology

A Galvanostatic Modeling for Preparation of Electrodeposited Nanocrystalline Coatings by Control of Current Density

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Journal of Materials Science & Technology 2012年第12期28卷 1071-1076页

作者： ali Mohammad Rashidi School of Engineering Razi UniversityP.O. Box 67149-67346 Kermanshah Iran

The correlation between the grain size of electrodeposited coatings and the current densities was modeled by considering galvanostatic conditions. In order to test the model by experimental results, nanocrystalline （NC） nickel samples were deposited at different current densities using a Watts bath. The grain size of the deposits was evaluated by X-ray diffraction （XRD） technique. Model predictions were validated by finding a curve being the best-fit to the experimental results which were gathered from literature for different NC coatings in addition to those data measured in this research for NC nickel coatings. According to our model, the variation of grain size with the reciprocal of the current density follows a power law. A good agreement between the experimental results and model predictions was observed which indicated that the derived analytical model is applicable for producting the nanocrystalline electrodeposits with the desired grain size by controling current density.

关键词： Electrodeposition Galvanostatic modeling Grain size control Nanocrystalline

New scoring system for intra-abdominal injury diagno- sis after blunt trauma

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Chinese Journal of Traumatology 2014年第1期17卷 19-24页

作者： Majid Sho.Jaee Gholamreza Faridaalaee Mahmoud Yousefifard Mehdi Yaseri Aft Arhami dolatabadi AnitaSabzghabaei ali Malekirastekenari Emergency Medicine Department Shahid Beheshti University of Medical Sciences Tehran Iran Emergency Medicine Department Urmia University of Medical Sciences Urmia Iran Department of Physiology School of Medicine Tehran University of Medical Sciences Tehran Iran Department of Epidemiology and Biostatistics Tehran University of Medical Sciences Tehran Iran

Objective： An accurate scoring system for intra-abdominal injury （IAI） based on clinical manifesta- tion and examination may decrease unnecessary CT scans, save time, and reduce healthcare cost. This study is de- signed to provide a new scoring system for a better diagno- sis of IAI after blunt trauma. Methods： This prospective observational study was performed from April 2011 to October 2012 on patients aged above 18 years and suspected with blunt abdominal trauma （BAT） admitted to the emergency department （ED） of Imam Hussein Hospital and Shohadaye Hafte Tir Hospital. All patients were assessed and treated based on Advanced Trauma Life Support and ED protocol. Diagnosis was done according to CT scan findings, which was considered as the gold standard. Data were gathered based on patient＇s history, physical exam, ultrasound and CT scan findings by a general practitioner who was not blind to this study. Chi- square test and logistic regression were done. Factors with significant relationship with CT scan were imported in multi- variate regression models, where a coefficient （13） was given based on the contribution of each of them. Scoring systemwas developed based on the obtained total [3 of each factor. Results： Altogether 261 patients （80.1% male） were enrolled （48 cases of IAI）. A 24-point blunt abdominal trauma scoring system （BATSS） was developed. Patients were di- vided into three groups including low （score〈8）, moderate （8≤score〈12） and high risk （score≥ 12）. In high risk group immediate laparotomy should be done, moderate group needs further assessments, and low risk group should be kept under observation. Low risk patients did not show positive CT-scans （specificity 100%）. Conversely, all high risk patients had positive CT-scan findings （sensitivity 100%）. The receiver operating characteristic curve indicated a close relationship between the results of CT scan and BATSS （sensitivity=99.3%）. Conclusion： The present scoring system furnishes a high precisio

关键词： Abdominal injuries Tomography, X-ray computed Diagnosis

Deep Learning-Based Robust DC Fault Protection Scheme for Meshed HVDC Grids

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2423-2434页

作者： Muhammad Zain Yousaf Hui Liu ali Raza ali Mustafa the School of Electrical Engineering Guangxi UniversityNanning 530004China the School of Electrical Engineering University of LahoreLahore 39161Pakistan the School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Fast and reliable detection of faults is a significant technical challenge in transient-based protection for a modular multi-level converter(MMC)based high voltage direct current(HVDC)*** is because existing protection schemes rely heavily upon setting a complicated protective threshold,the failure of which causes high DC-fault currents in HVDC grids,and MMC is prone to such strong transient *** this context,this paper proposes a DC-line fault diagnosis technique based on a tuned long-short-term memory(LSTM)algorithm to improve the response and accuracy of transient-based *** discrete wavelet transform(DWT)extracts the transient features of DC-line voltages in the frequency-time *** healthy and faulty samples are incorporated during training even by considering the noise *** training,numerous test samples are run to evaluate the proposed algorithm’s robustness under various fault *** results show the proposed algorithm can detect DC faults and has a high recognition accuracy of 98.6%.Compared to contemporary techniques,it can perform well to identify DC-line faults because of the efficient training of characteristic features.

关键词： High voltage direct current(HVDC) longshort-term-memory(LSTM) primary protection voltage source converters(VSC)

Seed Mediated Growth of Gold Nanoparticles Based on Liquid Arc Discharge

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Plasma Science and Technology 2013年第4期15卷 376-381页

作者： ali Akbar ASHKARRAN Department of Physics Faculty of Basic Sciences University of MazandaranBabolsar Iran

We report studies on the growth of gold nanoparticles by a seed-mediated approach in solution. The synthetic method is adapted from one we published earlier （Ashkarran et al. Appl. Phys. A 2009, 96, 423）. The synthesized gold nanoparticles were characterized by X-ray diffraction （XRD）, dynamic light scattering （DLS）, UV-Vis spectroscopy, optical imaging and atomic force microscopy （AFM）. Optical absorption spectroscopy of the prepared samples at 15 A arc current in HAuCI4 solution shows a surface plasmon resonance around 520 nm. It is found that sodium citrate acts as a stabilizer and surface capping agent of the colloidal nanoparticles. The intensity of the plasmonic peak of the prepared gold nanoparticles for 1 minute arc duration gradually increases due to seed mediation for up to 6 hours. The formation time of gold nanoparticles at higher seed concentrations is less than that at lower seed concentrations.

关键词： gold nanoparticles liquid arc discharge seed mediation optical properties

Temporal pattern mining from user-generated content

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Digital Communications and Networks 2022年第6期8卷 1027-1039页

作者： Adnan ali Jinlong Li Huanhuan Chen ali Kashif Bashir School of Computer Science and Technology University of Science and Technology of ChinaHefei230026AnhuiChina Department of Computing and Mathematics Manchester Metropolitan UniversityManchesterM156BHUnited Kingdom Department of Computer Science and Mathematics Lebanese American UniversityBeirutLebanon Woxsen School of Business Woxsen UniversityIndia

Faster internet, IoT, and social media have reformed the conventional web into a collaborative web resulting in enormous user-generated content. Several studies are focused on such content;however, they mainly focus on textual data, thus undermining the importance of metadata. Considering this gap, we provide a temporal pattern mining framework to model and utilize user-generated content's metadata. First, we scrap 2.1 million tweets from Twitter between Nov-2020 to Sep-2021 about 100 hashtag keywords and present these tweets into 100 User-Tweet-Hashtag (UTH) dynamic graphs. Second, we extract and identify four time-series in three timespans (Day, Hour, and Minute) from UTH dynamic graphs. Lastly, we model these four time-series with three machine learning algorithms to mine temporal patterns with the accuracy of 95.89%, 93.17%, 90.97%, and 93.73%, respectively. We demonstrate that user-generated content's metadata contains valuable information, which helps to understand the users' collective behavior and can be beneficial for business and research. Dataset and codes are publicly available;the link is given in the dataset section.

关键词： Social media analysis Collaborative computing Social data Twitter data Temporal patterns mining Dynamic graphs

Polynomials of Degree-Based Indices for Three-Dimensional Mesh Network

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Computers, Materials & Continua 2020年第11期65卷 1271-1282页

作者： ali N.A.Koam ali Ahmad Department of Mathematics College of ScienceJazan UniversityJazan45142Saudi Arabia College of Computer Science and Information Technology Jazan UniversityJazan45142Saudi Arabia

In order to study the behavior and interconnection of network devices,graphs structures are used to formulate the properties in terms of mathematical *** network(meshnet)is a LAN topology in which devices are connected either directly or through some intermediate *** terminating and intermediate devices are considered as vertices of graph whereas wired or wireless connections among these devices are shown as edges of *** indices are used to reflect structural property of graphs in form of one real *** structural invariant has revolutionized the field of chemistry to identify molecular descriptors of chemical *** indices are extensively used for establishing relationships between the structure of nanotubes and their physico-chemical *** this paper a representation of sodium chloride(NaCl)is studied,because structure of NaCl is same as the Cartesian product of three paths of length exactly like a mesh *** this way the general formula obtained in this paper can be used in chemistry as well as for any degree-based topological polynomials of three-dimensional mesh networks.

关键词： Topological polynomials degree-based index three-dimensional mesh network chemical compounds