检索结果-南通市图书馆

Efficient Channel Estimation Techniques for MIMO Systems with 1-Bit ADC

China Communications 2020年第5期17卷 50-64页

作者： Hany SHussein Shaimaa Hussein Ehab mahmoud Mohamed Electrical Engineering Dept. College of EngineeringKing Khalid UniversityAbha 61411King of Saudi Arabia Electrical Engineering Dept. Faculty of EngineeringAswan UniversityAswan 81542Egypt Electrical Engineering Dept. College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir 11991King of Saudi Arabia

With a low resolution 1-bit ADC on its receiver(RX) side, MIMO with 1-bit ADC took a considerable step in the fulfillment of the hardware complexity constrains of the internet of things(IoT) PHY layer design. However, applying 1-bit ADC at MIMO RX results in severe nonlinear quantization error. By which, almost all received signal amplitude information is completely distorted. Thus, MIMO channel estimation is considered as a major barrier towards practical realization of 1-bit ADC MIMO system. In this paper, two efficient sparsity-based channel estimation techniques are proposed for 1-bit ADC MIMO systems, namely the low complexity sparsity-based channel estimation(LCSCE), and the iterative adaptive sparsity channel estimation(IASCE). In these techniques, the sparsity of the 1-bit ADC MIMO channel is exploited to propose a new adaptive and iterative compressive sensing(CS) recovery algorithm to handle the 1-bit ADC quantization effect. The proposed algorithms are tested with the state-of-the-art 1-bit ADC MIMO constant envelope modulation(MIMO-CEM). The 1-bit ADC MIMO-CEM system is chosen as it fulfills both energy and hardware complexity constraints of the IoT PHY layer. Simulation results reveal the high effectiveness of the proposed algorithms in terms of spectral efficiency(SE) and computational complexity. The proposed LCSCE reduces the computational complexity of the 1-bit ADC MIMO-CEM channel estimation by 86%, while the IASCE reduces it by 96% compared to the recent techniques of MIMO-CEM channel estimation. Moreover, the proposed LCSCE and IASCE improve the spectrum efficiency by 76 % and 73 %, respectively, compared to the recent techniques.

关键词： channel estimation 1-bit ADC MIMO sparsity recovery compressive sensing Internet of things

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Geometrically Nonlinear Analysis of Structures Using Various Higher Order Solution Methods: A Comparative Analysis for Large Deformation

引用

Computer Modeling in Engineering & Sciences 2019年第12期121卷 877-907页

作者： Ali Maghami Farzad Shahabian Seyed mahmoud Hosseini Civil Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran Industrial Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran

The suitability of six higher order root solvers is examined for solving the nonlinear equilibrium equations in large deformation analysis of *** applied methods have a better convergence rate than the quadratic Newton-Raphson *** six methods do not require higher order derivatives to achieve a higher convergence *** algorithms are developed to use the higher order methods in place of the Newton-Raphson method to solve the nonlinear equilibrium equations in geometrically nonlinear analysis of *** higher order methods are applied to both continuum and discrete problems(spherical shell and dome truss).The computational cost and the sensitivity of the higher order solution methods and the Newton-Raphson method with respect to the load increment size are comparatively *** numerical results reveal that the higher order methods require a lower number of iterations that the Newton-Raphson method to *** is also shown that these methods are less sensitive to the variation of the load increment *** it is indicated in numerical results,the average residual reduces in a lower number of iterations by the application of the higher order methods in the nonlinear analysis of structures.

关键词： Geometrically nonlinear analysis higher order methods predictor-corrector algorithms convergence rate sensitivity to the increment size

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Deep Learning Model for EEG-Based Lie Detection Test Using Spatial and Temporal Aspects

引用

Computers, Materials & Continua 2022年第12期73卷 5655-5669页

作者： Abeer Abdulaziz AlArfaj Hanan Ahmed Hosni mahmoud Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

Lie detection test is highly significant task due to its impact on criminology and *** lie detection test model using electroencephalogram(EEG)signals is studied in *** this paper we studied deep learning framework in lie detection test ***,we apply a preprocessing technique to utilize only a small fragment of the EEG image instead of the whole *** model describes a temporal feature map of the EEG signals measured during the lie detection test.A deep learning attention model(V-TAM)extracts the temporal map vector during the learning *** technique reduces computational time and lessens the overfitting in Deep Learning *** propose a Cascading attention model with a deep learning convolutional neural network(CNN).V-TAM model extracts local features and global features in separate paths spatial and ***,to enhance the EEG segmentation precision,a novel Visual-Temporal AttentionModel(V-TAM)is *** accuracy was evaluated using data measured from a sensor from a public dataset of 9512 subjects during fifteen minutes lie detection *** compared our model with three recent published *** proposed model attained the highest performance of(98.5%)with(p<0.01).The visual-temporal model of the proposed platform shows an optimized balance between prediction accuracy and time *** investigationwere performed to prove the correctness and reliability of the proposed method through sizing of the input data,proving its effectiveness in attaining satisfactory performance by using only a smaller size input data.

关键词： Lie detection EEG image deep learning machine learning

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Melting heat transfer effects on stagnation point flow of micropolar fluid saturated in porous medium with internal heat generation(absorption)

引用

Applied Mathematics and Mechanics(English Edition) 2014年第8期35卷 979-992页

作者： M.a.a.mahmoud S.E.WAHEED Department of Mathematics Faculty of ScienceBenha University 13518BenhaEgypt Department of Mathematics and Statistic Faculty of ScienceTaif University 21974TaifKingdom of Saudi Arabia

The effect of melting heat transfer on the two dimensional boundary layer flow of a micropolar fluid near a stagnation point embedded in a porous medium in the presence of internal heat generation/absorption is investigated. The governing non-linear partial differential equations describing the problem are reduced to a system of non-linear ordinary differential equations using similarity transformations solved numerically using the Chebyshev spectral method. Numerical results for velocity, angular velocity and temperature profiles are shown graphically and discussed for different values of the inverse Darcy number, the heat generation/absorption parameter, and the melting parameter. The effects of the pertinent parameters on the local skin-friction coefficient, the wall couple stress, and the local Nusselt number are tabulated and discussed. The results show that the inverse Darcy number has the effect of enhancing both velocity and temperature and suppressing angular velocity. It is also found that the local skin-friction coefficient decreases, while the local Nusselt number increases as the melting parameter increases.

关键词： melting effect stagnation point micropolar fluid porous medium heat generation (absorption)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Brain Cancer Tumor Classification from Motion-Corrected MRI Images Using Convolutional Neural Network

引用

Computers, Materials & Continua 2021年第8期68卷 1551-1563页

作者： Hanan Abdullah Mengash Hanan A.Hosni mahmoud Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Science College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer and Systems Engineering Faculty of EngineeringUniversity of AlexandriaAlexandriaEgypt

Detection of brain tumors in MRI images is the first step in brain cancer *** accuracy of the diagnosis depends highly on the expertise of ***,automated diagnosis of brain cancer from MRI is receiving a large amount of ***,MRI tumor detection is usually followed by a biopsy(an invasive procedure),which is a medical procedure for brain tumor *** is of high importance to devise automated methods to aid radiologists in brain cancer tumor diagnosis without resorting to invasive *** neural network(CNN)is deemed to be one of the best machine learning algorithms to achieve high-accuracy results in tumor identification and *** this paper,a CNN-based technique for brain tumor classification has been *** proposed CNN can distinguish between normal(no-cancer),astrocytoma tumors,gliomatosis cerebri tumors,and glioblastoma *** implemented CNN was tested on MRI images that underwent a motion-correction *** CNN was evaluated using two performance measurement *** first one is a k-fold cross-validation testing method,in which we tested the dataset using k=8,10,12,and *** best accuracy for this procedure was 96.26%when k=*** overcome the over-fitting problem that could be occurred in the k-fold testing method,we used a hold-out testing method as a second evaluation *** results of this procedure succeeded in attaining 97.8%accuracy,with a specificity of 99.2%and a sensitivity of 97.32%.With this high accuracy,the developed CNN architecture could be considered an effective automated diagnosis method for the classification of brain tumors from MRI images.

关键词： Classification convolutional neural network tumor classification MRI deep learning k-fold cross classification

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

NUMERICAL PREDICTIONS AND EXPERIMENTAL VALIDATIONS OF DUCTILE DAMAGE EVOLUTION IN SHEET METAL FORMING PROCESSES

引用

Acta Mechanica Solida Sinica 2012年第6期25卷 638-650页

作者： Farhad Haji Aboutalebi mahmoud Farzin Mohammad Mashayekhi Department of Mechanical Engineering University of Isfahan Department of Mechanical Engineering Isfahan University of Technology

Prediction of forming limit in sheet metal forming is among the most important challenges confronting researchers. In this paper, a fully coupled elastic-plastic-damage model has been developed and implemented into an explicit code. Due to the adoption of the plane stress and finite strain theories, model can predict deformation and damage of parts quickly and accurately. Also, damage initiation, propagation, and fracture in some operations are predicted and validated with experiments. It is concluded that finite strain combined with continuum damage mechanics can be used as a quick tool to predict ductile damage, fracture, and forming limits in sheet metal forming processes.

关键词： ductile damage finite strain fracture sheet metal forming

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Arithmetic Optimization with Deep Learning Enabled Anomaly Detection in Smart City

引用

Computers, Materials & Continua 2022年第10期73卷 381-395页

作者： mahmoud Ragab Maha Farouk S.Sabir Information Technology Department Faculty of Computing and Information TechnologyKing Abdulaziz UniversityJeddah21589Saudi Arabia Centre of Artificial Intelligence for Precision Medicines King Abdulaziz UniversityJeddah21589Saudi Arabia Mathematics Department Faculty of ScienceAl-Azhar UniversityNaser City11884CairoEgypt Information Systems Department Faculty of Computing and Information Technology King Abdulaziz UniversityJeddah21589Saudi Arabia

In recent years,Smart City Infrastructures(SCI)have become familiar whereas intelligent models have been designed to improve the quality of living in smart ***,anomaly detection in SCI has become a hot research topic and is widely explored to enhance the safety of *** increasing popularity of video surveillance system and drastic increase in the amount of collected videos make the conventional physical investigation method to identify abnormal actions,a laborious *** this background,Deep Learning(DL)models can be used in the detection of anomalies found through video surveillance *** current research paper develops an Internet of Things Assisted Deep Learning Enabled Anomaly Detection Technique for Smart City Infrastructures,named(IoTAD-SCI)*** aim of the proposed IoTAD-SCI technique is to mainly identify the existence of anomalies in smart city ***,IoTAD-SCI technique involves Deep Consensus Network(DCN)model design to detect the anomalies in input video *** addition,Arithmetic Optimization Algorithm(AOA)is executed to tune the hyperparameters of the DCN ***,ID3 classifier is also utilized to classify the identified objects in different *** experimental analysis was conducted for the proposed IoTADSCI technique upon benchmark UCSD anomaly detection dataset and the results were inspected under different *** simulation results infer the superiority of the proposed IoTAD-SCI technique under different metrics.

关键词： Object detection anomaly detection smart city infrastructure deep learning parameter tuning

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Temporal trends of hydro-climatic variables and their relevance in water resource management

引用

International Journal of Sediment Research 2021年第1期36卷 63-75页

作者： Karim Solaimani mahmoud Habaibnejad Abdollah Pirnia GIS Centre University of Agricultural and Natural Resources of Sari Department of Watershed Management University of Agricultural and Natural Resources of Sari

Identification of temporal changes in hydrological regimes of river basins is an important topic in contemporary hydrology because of the potential impacts of climate change on river flow *** this purpose,long-term historical records of rainfall(P),runoff(Q) and other climatic factors were used to investigate hydrological variability and trends in the Tajan River Basin over the period *** evaporation(E),rainfall variability index(d),evaporation ratio(CE) and runoff ratio(CQ) were estimated from the available hydroclimatological ***-Kendall trend analysis and nonparametric Sen’s slope estimates were performed on the respective time series variables to detect monotonic trend direction and magnitude of change over *** variability index showed that1973 was the wettest year(δ=+2.039) while 1985 was the driest(δ=-1.584).Also,decades 69-78 and89-98 were recognized as the wettest and driest decades *** gradient of variation of climatological parameters showed that during the study period,all three parameters of rainfall,evaporation and runoff have decreased and the variations of rainfall and evaporation were significant at the95% *** of hydrological changes due of dam construction(1999) showed that the amount and annual distribution of discharge were completely different pre and post-dam *** decreased in high water months and increased in low water months to meet water supply demands,especially for *** relationship between temperature and rainfall trends is compared for three stations in Mazandaran Province(Gorgan,Babolsar and Ramsar) from 1956 to 2003 and nine other stations with different statistical periods of 19-36 years,relating trends to northern hemisphere and global *** in temperature were accompanied by decreases in rainfall,and vice *** trends were not observed in northern hemisphere and world scales,where temperature increases are accompanied b

关键词： Climate change Human activity Hydroclimatological Trend analysis Mazandaran Tajan basin

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Torsional Wave in a Dissipative Cylindrical Shell Under Initial Stresses

引用

Computers, Materials & Continua 2022年第2期70卷 3021-3030页

作者： mahmoud M.Selim Khaled A.Gepreel Department of Mathematics-College of Sciences&Humanities in Al Aflaj Prince Sattam bin Abdulaziz UniversityAl-Aflaj11912KSA Department of Mathematics Suez Faculty of ScienceSuez UniversityEgypt Department of Mathematics Faculty of ScienceTaif UniversityTaif21944Saudi Arabia

The dispersion relation of torsional wave in a dissipative,incompressible cylindrical shell of infinite length incorporating initial stresses effects is *** governing equation and closed form solutions are derived with the aid of Biot’s *** velocity and damping of torsional wave are obtained analytically and the influences of dissipation and initial stresses are studied in *** proposed a new method for obtaining the phase and damping velocities of torsional wave in a complex *** results analyzing the torsional wave propagation incorporating initial stress effects are analyzed and presented in *** analytical and numerical solutions reveal that,the dissipation as well as the initial stresses have notable impacts on the phase velocity of torsional wave in a pre-stressed dissipative cylindrical *** numerical results reveal that,the initial stresses and dissipation,considerably,effect the phase velocity of the torsional *** has been observed that,any change in dissipation parameter(δ)produces a substantial change in damping velocity of torsional *** addition,it can be seen that,the phase velocity increases as the initial stress parameter ***,the result of numerical simulation illustrated the influence of dissipation and initial stresses on damping and phase velocities of torsional wave *** conclusion made shown the consistency with the Biot’s incremental deformation theory,and the effective on model such as engineering mechanics and displacement of particles.

关键词： Propagation torsional wave dissipation cylindrical shell initial stress

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Stabilizing soft clay using geo-foam beads and cement bypass dust

引用

Underground Space 2020年第4期5卷 292-297页

作者： Essam Farouk Badrawi mahmoud Samir El-kady Structural Engineering Department Faculty of EngineeringZagazig UniversityEgypt Civil Engineering Department Jouf UniversitySaudi Arabia

Soft clays are usually classified according to their undrained shear strength,*** of Su less than 12.5 kPa are associated with very soft *** addition to their low shear strength,soft clays exhibit high compressibility upon ***,soft clays are considered to be problematic for foundation ***-foam is an industrial material that is characterized by a very low unit weight(20 kg/m^(3) on average)compared to that of the *** density of expanded polystyrene(EPS)ranges from 1.0%to 2.5%,which results in a compressive strength ranging between 70 kPa and 140 kPa and an elastic modulus ranging between 5 MPa and 12 *** geofoam blocks are used in a wide range of geotechnical applications as a lightweight fill *** main objective of this study was to investigate the geotechnical properties of soft clays containing geo-foam beads and cement bypass dust(CBPD).We also investigated the viability of preparing low-strength excavatable fill *** study the effect of(geofoam beads+CBPD)/soft clay on the fluid-state and hardened properties of new fill,we conducted experiments on two groups of mixtures(A&B).Each mixture contained different ratios of geo-foam beads and CBPD so that we could study the effect of the additive on the flow consistency,dry unit weight,unconfined compressive strength,and shear strength of the *** test results showed that the unconfined compressive strength of the studied mixtures without geo-foam ranged from 271.8 kPa to 1405.14 kPa at CBPD concentrations between 3.88%and 18.63%.The cohesion values for the group containing geo-foam ranged from 50 kPa to 20 kPa at geo-foam percentages between 0.32%and 1.35%.The friction angle of the group containing geo-foam ranged from 10 kPa to 22 kPa at CBPD percentages between 0.32%and 1.35%.Cement bypass dust can be successfully used to process self-compacting,self-leveling,excavatable and flowable fill material.

关键词： Geo-foam beads Cement bypass dust Flowable fill Shear strength

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：