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Deep Learning Based Signal Detection for Quadrature Spatial Modulation System

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China Communications 2024年第10期 78-85页

作者： Shu Dingyun Peng Yuyang Yue Ming Fawaz AL-Hazemi Mohammad meraj Mirza School of Computer Science and Engineering Macau University of Science and Technology Department of Computer and Network Engineering University of Jeddah Department of Computer Science College of Computers and Information Technology Taif University

With the development of communication systems, modulation methods are becoming more and more diverse. Among them, quadrature spatial modulation(QSM) is considered as one method with less capacity and high efficiency. In QSM, the traditional signal detection methods sometimes are unable to meet the actual requirement of low complexity of the system. Therefore, this paper proposes a signal detection scheme for QSM systems using deep learning to solve the complexity problem. Results from the simulations show that the bit error rate performance of the proposed deep learning-based detector is better than that of the zero-forcing(ZF) and minimum mean square error(MMSE) detectors, and similar to the maximum likelihood(ML) detector. Moreover, the proposed method requires less processing time than ZF, MMSE,and ML.

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S-curvature of isotropic Berwald metrics

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Science China Mathematics 2008年第12期51卷 2198-2204页

作者： Akbar TAYEBI Mehdi rafie-RAD Faculty of Science Department of Mathematics University of Qom Faculty of Mathematics and Computer Sciences Amirkabir University of Tecnology (Tehran Polytechnic)

Isotropic Berwald metrics are as a generalization of Berwald metrics. Shen proved that every Berwald metric is of vanishing S-curvature. In this paper, we generalize this fact and prove that every isotropic Berwald metric is of isotropic S-curvature. Let F = α + β be a Randers metric of isotropic Berwald curvature. Then it corresponds to a conformal vector field through navigation representation.

关键词： S-curvature isotropic Berwald metric isotropic S-curvature navigation representation 53C60 53C25

Cattaneo-Christov heat and mass flux model for 3D hydrodynamic flow of chemically reactive Maxwell liquid

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Applied Mathematics and Mechanics(English Edition) 2017年第10期38卷 1347-1356页

作者： S.A.SHEHZAD T.HAYAT A.ALSAEDI M.A.meraj Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of ScienceKing Abdulaziz University

This research focuses on the Cattaneo-Christov theory of heat and mass flux for a three-dimensional Maxwell liquid towards a moving surface. An incompressible laminar flow with variable thermal conductivity is considered. The flow generation is due to the bidirectional stretching of sheet. The combined phenomenon of heat and mass transport is accounted. The Cattaneo-Christov model of heat and mass diffusion is used to develop the expressions of energy and mass species. The first-order chemical reaction term in the mass species equation is considered. The boundary layer assumptions lead to the governing mathematical model. The homotopic simulation is adopted to visualize the results of the dimensionless flow equations. The graphs of velocities, temperature, and concentration show the effects of different arising parameters. A numerical benchmark is presented to visualize the convergent values of the computed results. The results show that the concentration and temperature fields are decayed for the Cattaneo^Christov theory of heat and mass diffusion.

关键词： Cattaneo-Christov theory chemical reactive flow temperature-dependentconductivity Maxwell liquid

Tree-Temperature Monitoring for Frost Protection of Orchards in Semi-Arid Regions Using Sprinkler Irrigation

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Agricultural Sciences in China 2009年第1期8卷 98-107页

作者： Ali Asghar Ghaemi Mohammad rafie rafiee Ali Reza Sepaskhah Irrigation Department College of AgricultureShiraz University

Automated over-tree sprinkler irrigation systems were developed and tested in two orchards located in two separate locations in southern Iran （a 0.17 ha peach orchard and a 0.24 ha orange orchard） to protect peach blossoms and orange trees leaves and fruits from low temperature damage. The experiment used a system that monitored the trees and air temperatures using two thermistors. The water application rate by the irrigation system was determined by an energy balance as implemented by the software FROSTPRO, In the peach orchard, the system was tested during three frost events during the spring of 2003 and three other events during the spring of 2004. The system successfully kept peach flowers above the critical temperature, i.e., -4.0℃ in spring 2004 （control block -4.12℃, and sprinkled block ＋0.5℃） during all events. Similar results were obtained in the orange orchard during three frost events in the winter of 2004, during which the tree temperatures were at least 2.5℃ above the critical temperature. Results from field tests show that the system can effectively protect the peach blossoms from damage. Determination done after the frost events showed a 12% blossom kill in the sprinkled blocks while in the unsprinkled control block a 41.5% blossom kill. Calculations indicated that when using variable application rates, the amount of water used can be reduced by 54.3%. Spatial distribution of minimum temperatures during the three frosts was also studied in Jahrom, Iran. Results showed a significant temperature control in the experimental block, especially in the central part of the orchard, but the block margins （about 3.6% of the total area） were at the risk of low temperature due to the wind drift effects.

关键词： automated sprinkler irrigation FROSTPORO frost protection peach orchard orange orchard

Static strength analysis of dragonfly inspired wings for biomimetic micro aerial vehicles

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Chinese Journal of Aeronautics 2016年第2期29卷 411-423页

作者： Praveena Nair Sivasankaran Thomas Arthur Ward Rubentheren Viyapuri Mohd rafie Johan Department of Mechanical Engineering University of Malaya

This article examines the suitability of fabricating artificial, dragonfly-like, wing frames from materials that are commonly used in unmanned aircraft （balsa wood, black graphite carbon fiber and red prepreg fiberglass）. Wing frames made with Type 321 stainless steel are also examined for comparison. The purpose of these wings is for future use in biomimetic micro aerial vehicles （BMAV）. BMAV are a new class of unmanned micro-sized aerial vehicles that mimic flying biolog- ical organisms （like flying insects）. Insects, such as dragonflies, possess corrugated and complex vein structures that are difficult to mimic. Simplified dragonfly-like wing frames were fabricated from these materials and then a nano-composite film was adhered to them, which mimics the membrane of an actual dragonfly. Finite element analysis simulations were also performed and compared to experimental results. The results showed good agreement （less than 10% difference for all cases）. Analysis of these results shows that stainless steel is a poor choice for this wing configuration, pri- marily because of the aggressive oxidation observed. Steel, as well as balsa wood, also lacks flexi- bility. In comparison, black graphite carbon fiber and red prepreg fiberglass offer some structural advantages, making them more suitable for consideration in future BMAV applications.

关键词： Biomimetic micro aerialvehicle Carbon fiber Finite element analysis Glass fiber Wing membrane Wing structure

Road Traffic Accident Fatalities and its Association with Key SocioDemographic Determinants in Nashik,Maharashtra:A Recurring Challenge

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Journal of Forensic Science and Medicine 2022年第2期8卷 52-56页

作者： Tej Bahadur Chhetri Syed meraj Ahmed Departments of Forensic Medicine Community Medicine Dr.Vasantrao Pawar Medical CollegeHospital and Research CentreNashikMaharashtraIndia

Background:Road traffic accidents are not a new phenomenon,rather ifs a disturbing occurrence which shows no sign of abating very ***,it remains one of those public health issues which even the most educated and civilized populations tend to ignore,primarily for the thrill of *** study aims to identify the outcome associated with vehicular accidents and its association with socio-demographic ***:This is a retrospective,record-based study of victims of road traffic accidents admitted in a tertiary care hospital in Nashik,*** data would include records from the 2018 to *** variables will include the socio-demographic factors,site of injuries and its severity.A descriptive analysis would be done by SPSS software to find out the prevalence of vehicular accidents,association of site of injury with age and severity of the *** approval would be taken before the initiation of the ***:A total of486 victims ofRTAs were included from the medical records of the casualty of a tertiary care hospital,out of which 330 were from the year 2018 and 156 from 2019.A look at the sociodemographic profiles of the RTA victims showed that females comprised only 19.3%(2018)and 18.6%(2019)of the total victims in road traffic accidents,while majority,80.6%(2018)and 81.4%(2019)were males during the same ***,we can also observe that both in 2018(38.5%)and 2019(50.6%)most of the road traffic accidents among the victims were of moderate ***:The need of the hour is to bring about a change from within through self-reflection of lawmakers,strict implementation of traffic rules and guidelines with hefty fines,lockup,and criminal punishment to habitual wrongdoers.

关键词： Age facial trauma gender head trauma multiple injuries road traffic accident

Darcy-Forchheimer flow of variable conductivity Jeffrey liquid with Cattaneo-Christov heat flux theory

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 557-566页

作者： M. A. meraj S.A. SHEHZAD T. HAYAT F.M. ABBASI A. ALSAEDI Department of Mathematics COMSATS Institute of Information TechnologySahiwal 57000Pakistan Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan NAAM Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics COMSATS Institute of Information TechnologyIslamabad 44000Pakistan

The role of the Cattaneo-Christov heat flux theory in the two-dimensional laminar flow of the Jeffrey liquid is discussed with a vertical sheet. The salient feature in the energy equation is accounted due to the implementation of the Cattaneo-Christov heat flux. A liquid with variable thermal conductivity is considered in the Darcy-Forchheimer porous space. The mathematical expressions of momentum and energy are coupled due to the presence of mixed convection. A highly nonlinear coupled system of equations is tackled with the homotopic algorithm. The convergence of the homotopy expressions is calculated graphically and numerically. The solutions of the velocity and temperature are expressed for various values of the Deborah number, the ratio of the relaxation time to the retardation time, the porosity parameter, the mixed convective parameter, the Darcy-Forchheimer parameter, and the conductivity parameter. The results show that the velocity and temperature are higher in Fourier＇s law of heat conduction cases in comparison with the Cattaneo-Christov heat flux model.

关键词： Darcy-Forchheimer porous medium variable conductivity Jeffrey liquid Cattaneo-Christov heat flux

Assessment of Sea Water Inundation Along Daboo Creek Area in Indus Delta Region, Pakistan

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Journal of Ocean University of China 2017年第6期16卷 1055-1060页

作者： ZIA Ibrahim ZAFAR Hina SHAHZAD Muhammad I. meraj Mohsin KAZMI Jamil H. National Institute of Oceanography (NIO) Karachi 75600 Pakistan Department of Geography University of Karachi 75270 Pakistan Earth & Atmospheric Remote Sensing Laboratory (EARL) Department of Meteorology COMSATS Institute of Information Technology (CIIT) Park Road Islamabad 45550 Pakistan

Indus Deltaic Region(IDR) in Pakistan is an erosion vulnerable coast due to the high deep water wave energy. Livelihood of millions of people depends on the fisheries and mangrove forests in IDR. IDR consists of many creeks where Daboo is a major creek located at southeast of the largest city of Pakistan, Karachi. Unfortunately, there has been no detailed study to analyze the damages of sea water intrusion at a large temporal and spatial scale. Therefore, this study is designed to estimate the effects of sea water inundation based on changing sea water surface salinity and sea surface temperature(SST). Sea surface salinity and SST data from two different surveys in Daboo creek during 1986 and 2010 are analyzed to estimate the damages and extent of sea water intrusion. Mean salinity has increased 33.33% whereas mean SST decreased 13.79% from 1987 to 2010. Spatio-temporal analysis of creek area using LANDSAT 5 Thematic mapper(TM) data for the years 1987 and 2010 shows significant amount of erosion at macro scale. Creek area has increased approximately 9.93%(260.86 m^2 per year) which is roughly equal to 60 extensive sized shrimp farms. Further Land Use Land Cover(LULC) analyses for years 2001 and 2014 using LANDSAT 7 Enhanced Thematic Mapper Plus(ETM+) has indicated 42.3% decrease in cultivated land. Wet mud flats have spread out at the inner mouth of creek with enormous increase of 123.3%. Significant sea water intrusion has increased the area of barren land by 37.9%. This also resulted in overall decrease of 6.7% in area covered by mangroves. Therefore, this study recorded a significant evidence of sea water intrusion in IDR that has caused serious damages to community living in the area, economical losses. Additionally, it has also changed the environment by reducing creek biological productivity as reported by earlier studies over other regions of the world.

关键词： sea water intrusion SST salinity Ambro creek CTD

Flapping wing micro-aerial-vehicle： Kinematics, membranes, and flapping mechanisms of ornithopter and insect flight

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Chinese Journal of Aeronautics 2016年第5期29卷 1159-1177页

作者： Mohd Firdaus Bin Abas Azmin Shakrine Bin Mohd rafie Hamid Bin Yusoff Kamarul Arifin Bin Ahmad Department of Aerospace Engineering Faculty of Engineering Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia Faculty of Mechanical Engineering Universiti Teknologi MARA Pulau Pinang 13500 Permatang Pauh Pulau Pinang Malaysia

The application of biomimetics in the development of unmanned-aerial-vehicles （UAV） has advanced to an exceptionally small scale of nano-aerial-vehicles （NAV）, which has surpassed its immediate predecessor of micro-aerial-vehicles （MAV）, leaving a vast range of development possi- bilities that MAVs have to offer. Because of the prompt advancement into the NAV research devel- opment, the true potential and challenges presented by MAV development were never solved, understood, and truly uncovered, especially under the influence of transition and low Reynolds number flow characteristics. This paper reviews a part of previous MAV research developments which are deemed important of notification; kinematics, membranes, and flapping mechanisms ranges from small birds to big insects, which resides within the transition and low Reynolds number regimes. This paper also reviews the possibility of applying a piezoelectric transmission used to pro- duce NAV flapping wing motion and mounted on a MAV, replacing the conventional motorized flapping wing transmission. Findings suggest that limited work has been done for MAVs matching these criteria. The preferred research approach has seen bias towards numerical analysis as compared to experimental analysis.

关键词： Flapping wing kinematics Insect Membrane wing Micro-air-vehicle Ornithopter