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Nodule Detection Using Local Binary Pattern Features to Enhance Diagnostic Decisions
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作者 Umar rashid Arfan Jaffar +2 位作者 muhammad rashid Mohammed S.Alshuhri Sheeraz Akram 《Computers, Materials & Continua》 SCIE EI 2024年第3期3377-3390,共14页
Pulmonary nodules are small, round, or oval-shaped growths on the lungs. They can be benign (noncancerous) or malignant (cancerous). The size of a nodule can range from a few millimeters to a few centimeters in diamet... Pulmonary nodules are small, round, or oval-shaped growths on the lungs. They can be benign (noncancerous) or malignant (cancerous). The size of a nodule can range from a few millimeters to a few centimeters in diameter. Nodules may be found during a chest X-ray or other imaging test for an unrelated health problem. In the proposed methodology pulmonary nodules can be classified into three stages. Firstly, a 2D histogram thresholding technique is used to identify volume segmentation. An ant colony optimization algorithm is used to determine the optimal threshold value. Secondly, geometrical features such as lines, arcs, extended arcs, and ellipses are used to detect oval shapes. Thirdly, Histogram Oriented Surface Normal Vector (HOSNV) feature descriptors can be used to identify nodules of different sizes and shapes by using a scaled and rotation-invariant texture description. Smart nodule classification was performed with the XGBoost classifier. The results are tested and validated using the Lung Image Consortium Database (LICD). The proposed method has a sensitivity of 98.49% for nodules sized 3–30 mm. 展开更多
关键词 Pulmonary nodules SEGMENTATION HISTOGRAM THRESHOLDING
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CNN-based segmentation frameworks for structural component and earthquake damage determinations using UAV images
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作者 Taisei Saida muhammad rashid +3 位作者 Yudai Nemoto Shota Tsukamoto Takehiko Asai Mayuko Nishio 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第2期359-369,共11页
Buildings undergo various kinds of structural damage during earthquakes,and damage detection and functional assessment of these structures in the aftermath of the events have been challenging issues.Under these circum... Buildings undergo various kinds of structural damage during earthquakes,and damage detection and functional assessment of these structures in the aftermath of the events have been challenging issues.Under these circumstances,computer vision techniques offer a promising solution by automating the inspection process.This study presents an effective methodology for automatic structural components and damage detection using unmanned aerial vehicle(UAV)images of damaged buildings.Two types of neural network architectures are considered for appropriate feature extractions in different task detections.The feature pyramid network(FPN)is employed for crack,spall,rebar,and component damage segmentation,while the UNet++network is utilized for the damage state.For network training and validation,a total of 3805 original images of size 1920×1080 pixels are processed by the proposed method and reduced the image pixels.From the FPN,the achieved highest intersection over unions(IoUs)were 0.59,0.93,0.42,and 0.99 for crack,spall,rebar,and components,respectively.These predicted labels were found in close agreement with the labels.Similarly,the UNet++recognized the semantic information and damage state with an IoU of 0.72.This demonstrated the applicability of the proposed method for automated post-earthquake building inspection process accurately without information loss from the original images. 展开更多
关键词 computer vision semantic segmentation component segmentation damage evaluation FPN UNet++
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A Coprocessor Architecture for 80/112-bit Security Related Applications
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作者 muhammad rashid Majid Alotaibi 《Computers, Materials & Continua》 SCIE EI 2023年第3期6849-6865,共17页
We have proposed a flexible coprocessor key-authentication architecture for 80/112-bit security-related applications over GF(2m)field by employing Elliptic-curve Diffie Hellman(ECDH)protocol.Towards flexibility,a seri... We have proposed a flexible coprocessor key-authentication architecture for 80/112-bit security-related applications over GF(2m)field by employing Elliptic-curve Diffie Hellman(ECDH)protocol.Towards flexibility,a serial input/output interface is used to load/produce secret,public,and shared keys sequentially.Moreover,to reduce the hardware resources and to achieve a reasonable time for cryptographic computations,we have proposed a finite field digit-serial multiplier architecture using combined shift and accumulate techniques.Furthermore,two finite-statemachine controllers are used to perform efficient control functionalities.The proposed coprocessor architecture over GF(2^(163))and GF(2^(233))is programmed using Verilog and then implemented on Xilinx Virtex-7 FPGA(field-programmable-gate-array)device.For GF(2^(163))and GF(2^(233)),the proposed flexible coprocessor use 1351 and 1789 slices,the achieved clock frequency is 250 and 235MHz,time for one public key computation is 40.50 and 79.20μs and time for one shared key generation is 81.00 and 158.40μs.Similarly,the consumed power over GF(2^(163))and GF(2^(233))is 0.91 and 1.37mW,respectively.The proposed coprocessor architecture outperforms state-of-the-art ECDH designs in terms of hardware resources. 展开更多
关键词 COPROCESSOR design key-authentication wireless sensor nodes RFID ECDH FPGA
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Preventing Cloud Network from Spamming Attacks Using Cloudflare and KNN
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作者 muhammad Nadeem Ali Arshad +4 位作者 Saman Riaz SyedaWajiha Zahra muhammad rashid Shahab S.Band Amir Mosavi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2641-2659,共19页
Cloud computing is one of the most attractive and cost-saving models,which provides online services to end-users.Cloud computing allows the user to access data directly from any node.But nowadays,cloud security is one... Cloud computing is one of the most attractive and cost-saving models,which provides online services to end-users.Cloud computing allows the user to access data directly from any node.But nowadays,cloud security is one of the biggest issues that arise.Different types of malware are wreaking havoc on the clouds.Attacks on the cloud server are happening from both internal and external sides.This paper has developed a tool to prevent the cloud server from spamming attacks.When an attacker attempts to use different spamming techniques on a cloud server,the attacker will be intercepted through two effective techniques:Cloudflare and K-nearest neighbors(KNN)classification.Cloudflare will block those IP addresses that the attacker will use and prevent spamming attacks.However,the KNN classifiers will determine which area the spammer belongs to.At the end of the article,various prevention techniques for securing cloud servers will be discussed,a comparison will be made with different papers,a conclusion will be drawn based on different results. 展开更多
关键词 Intrusion prevention system SPAMMING KNN classification SPAM cyber security BOTNET
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A Flexible Architecture for Cryptographic Applications: ECC and PRESENT
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作者 muhammad rashid Omar S.Sonbul +3 位作者 muhammad Arif Furqan Aziz Qureshi Saud.S.Alotaibi Mohammad H.Sinky 《Computers, Materials & Continua》 SCIE EI 2023年第7期1009-1025,共17页
This work presents a flexible/unified hardware architecture of Elliptic-curve Cryptography(ECC)and PRESENT for cryptographic applications.The features of the proposed work are(i)computation of only the point multiplic... This work presents a flexible/unified hardware architecture of Elliptic-curve Cryptography(ECC)and PRESENT for cryptographic applications.The features of the proposed work are(i)computation of only the point multiplication operation of ECC over GF(2163)for a 163-bit key generation,(ii)execution of only the variant of an 80-bit PRESENT block cipher for data encryption&decryption and(iii)execution of point multiplication operation(ECC algorithm)along with the data encryption and decryption(PRESENT algorithm).To establish an area overhead for the flexible design,dedicated hardware architectures of ECC and PRESENT are implemented in the first step,and a sum of their hardware area is computed.Then,the implementation of the proposed flexible architecture for ECC and PRESENT algorithms is presented.Implementation results regarding the area,clock cycles,latency,clock frequency,and power after the place-and-route level on Xilinx Virtex-5,Virtex-6,and Virtex-7 FPGA devices are presented.Hence,the implementation results and comparisons show that the proposed architecture suits applications demanding flexible implementation of cryptographic applications. 展开更多
关键词 Flexible UNIFIED design ECC PRESENT FPGA
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Lung Cancer Detection Using Modified AlexNet Architecture and Support Vector Machine
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作者 Iftikhar Naseer Tehreem Masood +3 位作者 Sheeraz Akram Arfan Jaffar muhammad rashid muhammad Amjad Iqbal 《Computers, Materials & Continua》 SCIE EI 2023年第1期2039-2054,共16页
Lung cancer is the most dangerous and death-causing disease indicated by the presence of pulmonary nodules in the lung.It is mostly caused by the instinctive growth of cells in the lung.Lung nodule detection has a sig... Lung cancer is the most dangerous and death-causing disease indicated by the presence of pulmonary nodules in the lung.It is mostly caused by the instinctive growth of cells in the lung.Lung nodule detection has a significant role in detecting and screening lung cancer in Computed tomography(CT)scan images.Early detection plays an important role in the survival rate and treatment of lung cancer patients.Moreover,pulmonary nodule classification techniques based on the convolutional neural network can be used for the accurate and efficient detection of lung cancer.This work proposed an automatic nodule detection method in CT images based on modified AlexNet architecture and Support vector machine(SVM)algorithm namely LungNet-SVM.The proposed model consists of seven convolutional layers,three pooling layers,and two fully connected layers used to extract features.Support vector machine classifier is applied for the binary classification of nodules into benign andmalignant.The experimental analysis is performed by using the publicly available benchmark dataset Lung nodule analysis 2016(LUNA16).The proposed model has achieved 97.64%of accuracy,96.37%of sensitivity,and 99.08%of specificity.A comparative analysis has been carried out between the proposed LungNet-SVM model and existing stateof-the-art approaches for the classification of lung cancer.The experimental results indicate that the proposed LungNet-SVM model achieved remarkable performance on a LUNA16 dataset in terms of accuracy. 展开更多
关键词 Lung cancer alexnet luna16 computed tomography support vector machine
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Intelligent Sound-Based Early Fault Detection System for Vehicles
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作者 Fawad Nasim Sohail Masood +2 位作者 Arfan Jaffar Usman Ahmad muhammad rashid 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3175-3190,共16页
An intelligent sound-based early fault detection system has been proposed for vehicles using machine learning.The system is designed to detect faults in vehicles at an early stage by analyzing the sound emitted by the... An intelligent sound-based early fault detection system has been proposed for vehicles using machine learning.The system is designed to detect faults in vehicles at an early stage by analyzing the sound emitted by the car.Early detection and correction of defects can improve the efficiency and life of the engine and other mechanical parts.The system uses a microphone to capture the sound emitted by the vehicle and a machine-learning algorithm to analyze the sound and detect faults.A possible fault is determined in the vehicle based on this processed sound.Binary classification is done at the first stage to differentiate between faulty and healthy cars.We collected noisy and normal sound samples of the car engine under normal and different abnormal conditions from multiple workshops and verified the data from experts.We used the time domain,frequency domain,and time-frequency domain features to detect the normal and abnormal conditions of the vehicle correctly.We used abnormal car data to classify it into fifteen other classical vehicle problems.We experimented with various signal processing techniques and presented the comparison results.In the detection and further problem classification,random forest showed the highest results of 97%and 92%with time-frequency features. 展开更多
关键词 Sound classification signal processing random forest random tree time-frequency domain J48
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A Multi-Modal Deep Learning Approach for Emotion Recognition
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作者 H.M.Shahzad Sohail Masood Bhatti +1 位作者 Arfan Jaffar muhammad rashid 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1561-1570,共10页
In recent years,research on facial expression recognition(FER)under mask is trending.Wearing a mask for protection from Covid 19 has become a compulsion and it hides the facial expressions that is why FER under the ma... In recent years,research on facial expression recognition(FER)under mask is trending.Wearing a mask for protection from Covid 19 has become a compulsion and it hides the facial expressions that is why FER under the mask is a difficult task.The prevailing unimodal techniques for facial recognition are not up to the mark in terms of good results for the masked face,however,a multi-modal technique can be employed to generate better results.We proposed a multi-modal methodology based on deep learning for facial recognition under a masked face using facial and vocal expressions.The multimodal has been trained on a facial and vocal dataset.We have used two standard datasets,M-LFW for the masked dataset and CREMA-D and TESS dataset for vocal expressions.The vocal expressions are in the form of audio while the faces data is in image form that is why the data is heterogenous.In order to make the data homogeneous,the voice data is converted into images by taking spectrogram.A spectrogram embeds important features of the voice and it converts the audio format into the images.Later,the dataset is passed to the multimodal for training.neural network and the experimental results demonstrate that the proposed multimodal algorithm outsets unimodal methods and other state-of-the-art deep neural network models. 展开更多
关键词 Deep learning facial expression recognition multi-model neural network speech emotion recognition SPECTROGRAM covid-19
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Data-Driven Probabilistic S for Batsman Performance Prediction in a Cricket Match
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作者 Fawad Nasim muhammad Adnan Yousaf +2 位作者 Sohail Masood Arfan Jaffar muhammad rashid 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2865-2877,共13页
Batsmen are the backbone of any cricket team and their selection is very critical to the team’s success.A good batsman not only scores run but also provides stability to the team’s innings.The most important factor ... Batsmen are the backbone of any cricket team and their selection is very critical to the team’s success.A good batsman not only scores run but also provides stability to the team’s innings.The most important factor in selecting a batsman is their ability to score runs.It is a generally accepted notion that the future performance of a batsman can be predicted by observing and analyzing their past record.This hypothesis is based on the fact that a player’s batting aver-age is generally considered to be a good indicator of their future performance.We proposed a data-driven probabilistic system for batsman performance prediction in the game of cricket.It captures the dependencies between the runs scored by a batsman in consecutive balls.The system is evaluated using a dataset extracted from the Cricinfo website.The system is based on a Hidden Markov model(HMM).HMM is used to generate the prediction model to foresee players’upcoming performances.The first-order Markov chain assumes that the probabil-ity of a batsman scoring runs in the next ball is only dependent on how many runs he scored in the current ball.We use a data-driven approach to learn the para-meters of the HMM from data.A probabilistic matrix is made that predicts what scores the batter can do on the upcoming balls.The results show that the system can accurately predict the runs scored by a batsman in a ball. 展开更多
关键词 Probabilistic matrix hidden markov model batsman performance prediction
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Dynamic characteristics of nanoindentation in Ni:A molecular dynamics simulation study 被引量:4
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作者 muhammad Imran Fayyaz Hussain +1 位作者 muhammad rashid S.A.Ahmad 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期367-372,共6页
In this work,three-dimensional molecular dynamics simulation is carried out to elucidate the nanoindentation behaviour of single crystal Ni.The substrate indenter system is modelled using hybrid interatomic potentials... In this work,three-dimensional molecular dynamics simulation is carried out to elucidate the nanoindentation behaviour of single crystal Ni.The substrate indenter system is modelled using hybrid interatomic potentials including the manybody potential(embedded atom method) and two-body Morse potential.The spherical indenter is chosen,and the simulation is performed for different loading rates from 10 m/s to 200 m/s.Results show that the maximum indentation load and hardness of the system increase with the increase of velocity.The effect of indenter size on the nanoindentation response is also analysed.It is found that the maximum indentation load is higher for the large indenter whereas the hardness is higher for the smaller indenter.Dynamic nanoindentation is carried out to investigate the behaviour of Ni substrate to multiple loading-unloading cycles.It is observed from the results that the increase in the number of loading unloading cycles reduces the maximum load and hardness of the Ni substrate.This is attributed to the decrease in recovery force due to defects and dislocations produced after each indentation cycle. 展开更多
关键词 分子动力学模拟 纳米压痕 镍基板 动态特性 MORSE势 加载速率 相互作用势 嵌入原子法
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Molecular dynamics study of the mechanical characteristics of Ni/Cu bilayer using nanoindentation 被引量:3
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作者 muhammad Imran Fayyaz Hussain +1 位作者 muhammad rashid S.A.Ahmad 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期389-395,共7页
In the present work,a three-dimensional molecular dynamics simulation is carried out to perform the nanoindentation experiment on Ni single crystal.The substrate indenter system is modeled using hybrid interatomic pot... In the present work,a three-dimensional molecular dynamics simulation is carried out to perform the nanoindentation experiment on Ni single crystal.The substrate indenter system is modeled using hybrid interatomic potentials including the many-body potential embedded atom method(EAM),and two-body morse potential.To simulate the indentation process,a spherical indenter(diameter = 80 A,1 A=0.1 nm) is chosen.The results show that the mechanical behaviour of a monolithic Ni is not affected by crystalline orientation.To elucidate the effect of a heterogeneous interface, three bilayer interface systems are constructed,namely Ni(100)/Cu(111),Ni(110)/Cu(111),and Ni(111)/Cu(111).The simulations along these systems clearly describe that mechanical behaviour directly depends on the lattice mismatch. The interface with the smaller mismatch between the specified crystal planes is proved to be harder and vice versa.To describe the relationship between film thickness and interface effect,we choose various values of film thickness ranging from 20 A to 50 A to perform the nanoindentation experiment.It is observed that the interface is significant only for the relatively small thickness of film and the separation between interface and the indenter tip.It is shown that with the increase in film thickness,the mechanical behaviour of the film shifts more toward that of monolithic material. 展开更多
关键词 分子动力学模拟 纳米压痕 机械特性 薄膜厚度 嵌入原子方法 MORSE势 界面系统
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Structural, electronic, and optical properties of ZnO_(1-x)Se_x alloys using first-principles calculations 被引量:2
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作者 muhammad rashid Fayyaz Hussain +4 位作者 muhammad Imran S A Ahmad N A Noor M U Sohaib S M Alay-e-Abbas 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期581-588,共8页
The structural, electronic, and optical properties of binary ZnO, ZnSe compounds, and their ternary ZnO 1-x Se x alloys are computed using the accurate full potential linearized augmented plane wave plus local orbital... The structural, electronic, and optical properties of binary ZnO, ZnSe compounds, and their ternary ZnO 1-x Se x alloys are computed using the accurate full potential linearized augmented plane wave plus local orbital (FP-LAPW + lo) method in the rocksalt (B1) and zincblende (B3) crystallographic phases. The electronic band structures, fundamental energy band gaps, and densities of states for ZnO 1-x Se x are evaluated in the range 0 ≤ x ≤ 1 using Wu-Cohen (WC) generalized gradient approximation (GGA) for the exchange-correlation potential. Our calculated results of lattice parameters and bulk modulus reveal a nonlinear variation for pseudo-binary and their ternary alloys in both phases and show a considerable deviation from Vegard's law. It is observed that the predicted lattice parameter and bulk modulus are in good agreement with the available experimental and theoretical data. We establish that the composition dependence of band gap is semi-metallic in B1 phase, while a direct band gap is observed in B3 phase. The calculated density of states is described by taking into account the contribution of Zn 3d, O2p, and Se 4s, and the optical properties are studied in terms of dielectric functions, refractive index, reflectivity, and energy loss function for the B3 phase and are compared with the available experimental data. 展开更多
关键词 电子能带结构 三元合金 光学特性 全势线性缀加平面波 体积弹性模量 广义梯度近似 计算结果 晶格参数
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Theoretical investigations of half-metallic ferromagnetism in new Half-Heusler YCrSb and YMnSb alloys using first-principle calculations 被引量:1
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作者 M Atif Sattar muhammad rashid +3 位作者 M Raza Hashmi S A Ahmad muhammad Imran Fayyaz Hussain 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第10期386-392,共7页
Structural,electronic,and magnetic properties of new predicted half-Heusler YCrSb and YMnSb compounds within the ordered MgAgAs Clb-type structure are investigated by employing first-principal calculations based on de... Structural,electronic,and magnetic properties of new predicted half-Heusler YCrSb and YMnSb compounds within the ordered MgAgAs Clb-type structure are investigated by employing first-principal calculations based on density functional theory.Through the calculated total energies of three possible atomic placements,we find the most stable structures regarding YCrSb and YMnSb materials,where Y,Cr(Mn),and Sb atoms occupy the(0.5,0.5,0.5),(0.25,0.25,0.25),and(0,0,0) positions,respectively.Furthermore,structural properties are explored for the non-magnetic and ferromagnetic and anti-ferromagnetic states and it is found that both materials prefer ferromagnetic states.The electronic band structure shows that YCrSb has a direct band gap of 0.78 eV while YMnSb has an indirect band gap of 0.40 eV in the majority spin channel.Our findings show that YCrSb and YMnSb materials exhibit half-metallic characteristics at their optimized lattice constants of 6.67  and 6.56 ,respectively.The half-metallicities associated with YCrSb and YMnSb are found to be robust under large in-plane strains which make them potential contenders for spintronic applications. 展开更多
关键词 electronic structures density functional theory metals and alloys other ferromagnetic metals and alloys
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Profiling Casualty Severity Levels of Road Accident Using Weighted Majority Voting 被引量:1
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作者 Saba Awan Zahid Mehmood +4 位作者 Hassan Nazeer Chaudhry Usman Tariq Amjad Rehman Tanzila Saba muhammad rashid 《Computers, Materials & Continua》 SCIE EI 2022年第6期4609-4626,共18页
To determine the individual circumstances that account for a road traffic accident,it is crucial to consider the unplanned connections amongst various factors related to a crash that results in high casualty levels.An... To determine the individual circumstances that account for a road traffic accident,it is crucial to consider the unplanned connections amongst various factors related to a crash that results in high casualty levels.Analysis of the road accident data concentrated mainly on categorizing accidents into different types using individually built classification methods which limit the prediction accuracy and fitness of the model.In this article,we proposed a multi-model hybrid framework of the weighted majority voting(WMV)scheme with parallel structure,which is designed by integrating individually implemented multinomial logistic regression(MLR)and multilayer perceptron(MLP)classifiers using three different accident datasets i.e.,IRTAD,NCDB,and FARS.The proposed WMV hybrid scheme overtook individual classifiers in terms of modern evaluation measures like ROC,RMSE,Kappa rate,classification accuracy,and performs better than state-of-theart approaches for the prediction of casualty severity level.Moreover,the proposed WMV hybrid scheme adds up to accident severity analysis through knowledge representation by revealing the role of different accident-related factors which expand the risk of casualty in a road crash.Critical aspects related to casualty severity recognized by the proposed WMV hybrid approach can surely support the traffic enforcement agencies to develop better road safety plans and ultimately save lives. 展开更多
关键词 Prediction hybrid framework SEVERITY CLASS CASUALTY
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Hand dysfunction after transradial artery catheterization for coronary procedures 被引量:1
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作者 muhammad Ayyaz Ul Haq muhammad rashid +3 位作者 Chun Shing Kwok Chun Wai Wong James Nolan Mamas A Mamas 《World Journal of Cardiology》 CAS 2017年第7期609-619,共11页
AIM To sythesize the available literature on hand dysfunction after transradial catheterization.METHODS We searched MEDLINE and EMBASE. The search results were reviewed by two independent judicators for studies that m... AIM To sythesize the available literature on hand dysfunction after transradial catheterization.METHODS We searched MEDLINE and EMBASE. The search results were reviewed by two independent judicators for studies that met the inclusion criteria and relevant reviews. We included studies that evaluated any transradial procedure and evaluated hand function outcomes post transradial procedure. There were no restrictions based on sample size. There was no restriction on method of assessing hand function which included disability, nerve damage, motor or sensory loss. There was no restriction based on language of study. Data was extracted, these results were narratively synthesized.RESULTS Out of 555 total studies 13 studies were finally included in review. A total of 3815 participants with mean age of 62.5 years were included in this review. A variety of methods were used to assess sensory and motor dysfunction of hand. Out of 13 studies included, only 3 studies reported nerve damage with a combined incidence of 0.16%, 5 studies reported sensory loss, tingling and numbness with a pooled incidence of 1.52%. Pain after transradial access was the most common form of hand dysfunction(6.67%) reported in 3 studies. The incidence of hand dysfunction defined as disability, grip strength change, power loss or any other hand complication was incredibly low at 0.26%. Although radial artery occlusion was not our primary end point for this review, it was observed in 2.41% of the participants in total of five studies included.CONCLUSION Hand dysfunction may occur post transradial catheterisation and majority of symptoms resolve without any clinical sequel. 展开更多
关键词 Transradial access Transfemoral access Hand dysfunction
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Ab-initio investigation of AGeO_3(A=Ca, Sr) compounds via Tran Blaha-modified Becke Johnson exchange potential
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作者 Rasul Bakhsh Behram M A Iqbal +3 位作者 muhammad rashid M Atif Sattar Asif Mahmood Shahid M Ramay 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期375-382,共8页
We employ ab-initio calculations to analyze the mechanical, electronic, optical and also thermoelectric properties associated with AGeO_3(A = Ca, Sr) compounds. The full-potential linearized augmented plane wave(FP-LA... We employ ab-initio calculations to analyze the mechanical, electronic, optical and also thermoelectric properties associated with AGeO_3(A = Ca, Sr) compounds. The full-potential linearized augmented plane wave(FP-LAPW) technique in the generalized gradient approximation(GGA-PBEsol) and the lately designed Tran-Blaha-modified Becke-Johnson exchange potential are utilized to examine the mechanical and optoelectronic properties respectively. To explore the thermoelectric quality, we use the semi-classical Boltzmann transport theory. The particular structural stabilities regarding AGeO3_(A = Ca, Sr) materials are validated simply by computations from the elastic constants. The energy band structural framework and the density of states are displayed to indicate indirect bandgap under ambient conditions. The particular computed optical attributes that reveal prospective optoelectronic applications are usually elucidated simply by studying ε_1(0) and also E_g, which can be connected by means of Penn's design. The optical details uncover the actual suitability to power ranging products. Finally, the Boltz Tra P code is executed to analyze the actual thermoelectric properties, which usually presents that the increase of internal temperatures can enhance the electric conductivity, thermal conductivity and also the power factor, whilst Seebeck coefficient decreases. Therefore, the studied materials will also be ideal for thermoelectric products to understand helpful option for alternative energy resources. 展开更多
关键词 化合物 CA SR 约翰逊 全势线性缀加平面波 SEEBECK系数 热电性能 修改
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Molecular dynamics simulation of nanoscale surface diffusion of heterogeneous adatoms clusters
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作者 muhammad Imran Fayyaz Hussain +6 位作者 muhammad rashid muhammad Ismail Hafeez Ullah Yongqing Cai M Arshad Javid Ejaz Ahmad S A Ahmad 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期341-348,共8页
Molecular dynamics simulation employing the embedded atom method potential is utilized to investigate nanoscale surface diffusion mechanisms of binary heterogeneous adatoms clusters at 300 K, 500 K, and 700 K. Surface... Molecular dynamics simulation employing the embedded atom method potential is utilized to investigate nanoscale surface diffusion mechanisms of binary heterogeneous adatoms clusters at 300 K, 500 K, and 700 K. Surface diffusion of heterogeneous adatoms clusters can be vital for the binary island growth on the surface and can be useful for the formation of alloy-based thin film surface through atomic exchange process. The results of the diffusion process show that at 300 K, the diffusion of small adatoms clusters shows hopping, sliding, and shear motion; whereas for large adatoms clusters(hexamer and above), the diffusion is negligible. At 500 K, small adatoms clusters, i.e., dimer, show almost all possible diffusion mechanisms including the atomic exchange process; however no such exchange is observed for adatoms clusters greater than dimer. At 700 K, the exchange mechanism dominates for all types of clusters, where Zr adatoms show maximum tendency and Ag adatoms show minimum or no tendency toward the exchange process. Separation and recombination of one or more adatoms are also observed at 500 K and 700 K. The Ag adatoms also occupy pop-up positions over the adatoms clusters for short intervals. At 700 K, the vacancies are also generated in the vicinity of the adatoms cluster,vacancy formation, filling, and shifting can be observed from the results. 展开更多
关键词 分子动力学模拟 表面扩散 原子簇 纳米 原子团簇 异种 嵌入原子方法 交换过程
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Mechanical behavior of Cu-Zr bulk metallic glasses (BMGs): A molecular dynamics approach
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作者 muhammad Imran Fayyaz Hussain +2 位作者 muhammad rashid Yongqing Cai S.A.Ahmad 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第9期490-495,共6页
In the present work, three-dimensional molecular dynamics simulation is carried out to elucidate the nanoindentation behaviors of CuZr Bulk metallic glasses (BMGs). The substrate indenter system is modeled using hybri... In the present work, three-dimensional molecular dynamics simulation is carried out to elucidate the nanoindentation behaviors of CuZr Bulk metallic glasses (BMGs). The substrate indenter system is modeled using hybrid interatomic potentials including both many-body Finnis Sinclair (FS) and two-body Morse potentials. A spherical rigid indenter (diameter = 60(1 = 10-10 m)) is employed to simulate the indentation process. Three samples of BMGs including Cu25Zr75 , Cu50Zr50 , and Cu75Zr25 are designed and the metallic glasses are formed by rapid cooling from the melt state at about 2000 K. The radial distribution functions are analyzed to reveal the dynamical evolution of the structure of the atoms with different compositions and different cooling rates. The mechanical behavior can be well understood in terms of load-depth curves and Hardness-depth curves during the nanoindentation process. Our results indicate a positive linear relationship between the hardness and the Cu concentration of the BMG sample. To reveal the importance of cooling rate provided during the processing of BMGs, we investigate the indentation behaviors of Cu50Zr50 at three different quenching rates. Nanoindentation results and radial distribution function (RDF) curves at room temperature indicate that a sample can be made harder and more stable by slowing down the quenching rate. 展开更多
关键词 块体非晶合金 大块金属玻璃 力学行为 分子动力学方法 分子动力学模拟 径向分布函数 纳米压痕 冷却速度
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FPGA Implementation of Elliptic-Curve Diffie Hellman Protocol
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作者 Sikandar Zulqarnain Khan Sajjad Shaukat Jamal +1 位作者 Asher Sajid muhammad rashid 《Computers, Materials & Continua》 SCIE EI 2022年第10期1879-1894,共16页
This paper presents an efficient crypto processor architecture for key agreement using ECDH(Elliptic-curve Diffie Hellman)protocol over GF2163.The composition of our key-agreement architecture is expressed in consist... This paper presents an efficient crypto processor architecture for key agreement using ECDH(Elliptic-curve Diffie Hellman)protocol over GF2163.The composition of our key-agreement architecture is expressed in consisting of the following:(i)Elliptic-curve Point Multiplication architecture for public key generation(DESIGN-I)and(ii)integration of DESIGN-I with two additional routing multiplexers and a controller for shared key generation(DESIGN-II).The arithmetic operators used in DESIGN-I and DESIGNII contain an adder,squarer,a multiplier and inversion.A simple shift and add multiplication method is employed to retain lower hardware resources.Moreover,an essential inversion operation is operated using the Itoh-Tsujii algorithm with similar hardware resources of used squarer and multiplier units.The proposed architecture is implemented in a Verilog HDL.The implementation results are given on a Xilinx Virtex-7 FPGA(field-programmable gate array)device.For DESIGN-I and DESIGN-II over GF2163,(i)the utilized Slices are 3983 and 4037,(ii)the time to compute one public key and a shared secret is 553.7μs and 1170.7μs and(iii)the consumed power is 29μW and 57μW.Consequently,the achieved area optimized and power reduced results show that the proposed ECDH architecture is a suitable alternative(to generate a shared secret)for the applications that require low hardware resources and power consumption. 展开更多
关键词 Elliptic curve cryptography point multiplication key-agreement diffie hellman area optimized architecture FPGA
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Ab-initio calculations of bandgap tuning of In1-xGaxY(Y=N,P)alloys for optoelectronic applications
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作者 muhammad rashid Jamil M +3 位作者 Mahmood Q Shahid M Ramay Asif Mahmood A Ghaithan H M 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期467-474,共8页
The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influen... The III–V alloys and doping to tune the bandgap for solar cells and other optoelectronic devices has remained a hot topic of research for the last few decades.In the present article,the bandgap tuning and its influence on optical properties of In1-xGaxN/P,where(x=0.0,0.25,0.50,0.75,and 1.0)alloys are comprehensively analyzed by density functional theory based on full-potential linearized augmented plane wave method(FP-LAPW)and modified Becke and Johnson potentials(TB-mBJ).The direct bandgaps turn from 0.7 eV to 3.44 eV,and 1.41 eV to 2.32 eV for In1-xGaxN/P alloys,which increases their potentials for optoelectronic devices.The optical properties are discussed such as dielectric constants,refraction,absorption,optical conductivity,and reflection.The light is polarized in the low energy region with minimum reflection.The absorption and optical conduction are maxima in the visible region,and they are shifted into the ultraviolet region by Ga doping.Moreover,static dielectric constant e1(0)is in line with the bandgap from Penn’s model. 展开更多
关键词 density functional theory direct bandgap III-V semiconductors tuning of optical band gap solar cell applications
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