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Bandgap engineering to tune the optical properties of Be_xMg_(1-x)X(X=S, Se, Te) alloys

Chinese Physics B 2018年第1期27卷 415-423页

作者： B Sabir N A Noor M Rashid Fasih ud din Shahid M Ramay Asif Mahmood Centre for Advanced Studies in Physics Government College University Department of Physics School of Science University of Management and TechnologyLahore Pakistan Department of Physics COMSATS Institute of Information Technology Physics and Astronomy Department College of Science King Saud University Chemical Engineering Department College of Engineering King Saud University

Structural, electronic, and optical properties of alloys BexMgl-xX （X = S, Se, Te） in the assortment 0 〈 x 〈 1 were theoretically reported for the first time in zinc-blende （ZB） phase. The calculations were carried out by using full-potential linearized augmented plane wave plus local orbitals （FP-LAPW＋lo） formalism contained by the framework of density functional theory （DFT）. Wu--Cohen （WC） generalized gradient approximation （GGA）, based on optimization energy, has been applied to calculate these theoretical results. In addition, we used Becke and Johnson （mBJ-GGA） potential, modified form of GGA functional, to calculate electronic structural properties up to a high precision degree. The alloys were composed with the concentrations x = 0.25, 0.5, and 0.75 in pursuance of ＇special quasi-random structures＇（SQS） approach of Zunger for the restoration of disorder around the observed site of alloys in the first few shells. The structural parameters have been predicted by minimizing the total energy in correspondence of unit cell volume. Our alloys established direct band gap at different concentrations that make their importance in optically active materials. Furthermore, density of states was discussed in terms of the contribution of Be and Mg s and chalcogen （S, Se, and Te） s and p states and observed charge density helped us to investigate the bonding nature. By taking into consideration of immense importance in optoelectronics of these materials, the complex dielectric function was calculated for incident photon energy in the range 0--15 eV.

关键词： BexMgl-xX (X = S Se Te) alloys zinc-blende (ZB) phase density functional theory (DFT),electronic and optical properties

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Assessment of parameters effectiveness in the reserve estimation methods applicable to coal bed methane reservoirs

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Petroleum Research 2023年第1期8卷 44-53页

作者： Farzain ud din Kirmani Arshad Raza Muhammad Sarfraz Akram Raoof Gholami Institute of Energy and Environmental Engineering University of the PunjabLahorePakistan Department of Petroleum and Gas Engineering University of Engineering and TechnologyLahorePakistan Department of Petroleum Engineering King Fahd University of Petroleum and MineralsSaudi Arabia Department of Energy Resources University of StavangerStavangerNorway

The reserve estimation of coal bed methane(CBM)reservoirs is ascertained through the analytical methods(volumetric method,material balance equation and decline curve analysis).However,the adoption of reserve estimation methods depends on exploration stage and availability of the required *** study deals with the analytical assessment of parameters that participate in effecting the reserve estimation of CBM reservoirs through the analytical *** accurate measurement challenges always exist for the parameters which participate in the reserve estimation of the conventional and unconventional reservoirs because of the inclusion of limitations while ***,the impact of that measurement challenge must be *** study specifies the impact of parametric change on the reserve estimation of CBM reservoirs so that the degree of parametric effectiveness is *** values are adopted which are associated during the evaluation of input parameters for each method to determine the overall impact on potential of CBM *** reveal that change in specific parameters considering each method provide relatively more effect on estimation of ***,the measurement of parameters must be done accurately for assessing reserves of CBM reservoirs based on available methods.

关键词： Reserve estimation Coal bed methane Parameters effectiveness Analytical methods Numerical simulation

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Flexible Global Aggregation and Dynamic Client Selection for Federated Learning in Internet of Vehicles

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Computers, Materials & Continua 2023年第11期77卷 1739-1757页

作者： Tariq Qayyum Zouheir Trabelsi Asadullah Tariq Muhammad Ali Kadhim Hayawi Irfan ud din College of Information Technology United Arab Emirates UniversityAl Ain17551UAE Department of Computing School of EECSNational University of Sciences and TechnologyIslamabad44000Pakistan College of Technological Innovation Zayed UniversityAbu Dhabi144534UAE Department of Computer Science The Superior UniversityLahore54000Pakistan

Federated Learning(FL)enables collaborative and privacy-preserving training of machine learning models within the Internet of Vehicles(IoV)*** FL effectively tackles privacy concerns,it also imposes significant resource *** traditional FL,trained models are transmitted to a central server for global aggregation,typically in the *** approach often leads to network congestion and bandwidth limitations when numerous devices communicate with the same *** need for Flexible Global Aggregation and Dynamic Client Selection in FL for the IoV arises from the inherent characteristics of IoV *** include diverse and distributed data sources,varying data quality,and limited communication *** employing dynamic client selection,we can prioritize relevant and high-quality data sources,enhancing model *** address this issue,we propose an FL framework that selects global aggregation nodes dynamically rather than a single fixed *** global aggregation ensures efficient utilization of limited network resources while accommodating the dynamic nature of IoV data *** approach optimizes both model performance and resource allocation,making FL in IoV more effective and *** selection of the global aggregation node is based on workload and communication speed ***,our framework overcomes the constraints associated with network,computational,and energy resources in the IoV environment by implementing a client selection algorithm that dynamically adjusts participants according to predefined *** approach surpasses Federated Averaging(FedAvg)and Hierarchical FL(HFL)regarding energy consumption,delay,and accuracy,yielding superior results.

关键词： IoT Federated Learning sensors IoV OMNeT++ edge computing

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Effect of inclusion on high cycle fatigue response of a powder metallurgy tool steel

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Journal of Central South University 2012年第7期19卷 1773-1779页

作者：姚君曲选辉 Rafi-ud-din 何新波章林 State Key Laboratory for Advanced Metals and Materials(University of Science and Technology Beijing) School of Materials Science and Engineering University of Science and Technology Beijing

The high cycle fatigue response of a high V-alloyed powder metallurgy tool steel （AISI 11） with different inclusion sizes was studied. Two materials of this grade at a similar hardness of about HRC 60 were subjected to axial loading fatigue tests, tensile tests and fracture toughness measurements to investigate their mechanical properties. Large inclusion above 70 ~rn is indicated to be responsible for the tensile fracture which happens before yielding. The fatigue strength obtained up to 107 cycles is found to decrease from approximately 1 538 MPa to 1000 MPa with the inclusion size increasing above 30 Izm. The internally induced crack initiation is mainly attributed to the surface compressive residual stress of 300-450 MPa. Fractographic evaluation demonstrates that the crack initiation and propagation controlling factors of the two materials are almost the same, indicating that the two factors would be insignificantly affected by the inclusion size level. Paris sizes of the two materials both show a tendency to decrease as the ratio of stress intensity factor of crack origin to factor of fish-eye increases. The investigation into the relationship between stress intensity factors and fatigue life of the two materials further indicates that the high cycle fatigue behavior of AISI 11 is controlled by crack propagation.

关键词： powder metallurgy tool steel high cycle fatigue fractography fish-eye inclusion

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IoT Devices Authentication Using Artificial Neural Network

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Computers, Materials & Continua 2022年第2期70卷 3701-3716页

作者： Syed Shabih Ul Hasan Anwar Ghani Ikram ud din Ahmad Almogren Ayman Altameem Department of Computer Science and Software Engineering International Islamic University Islamabad45000Pakistan Department of Information Technology The University of Haripur22620HaripurPakistan Chair of Cyber Security Department of Computer ScienceCollege of Computer and Information SciencesKing Saud UniversityRiyadh11633Saudi Arabia Chair of Cyber Security Department of Natural and Engineering SciencesCollege of Applied Studies and Community ServicesKing Saud UniversityRiyadh11543Saudi Arabia

User authentication is one of the critical concerns of information *** tend to use strong textual passwords,but remembering complex passwords is hard as they often write it on a piece of paper or save it in their mobile *** passwords are slightly unprotected and are easily *** attacks include dictionary,shoulder surfing,and brute *** passwords overcome the shortcomings of textual passwords and are designed to aid memorability and ease of *** paper proposes a Process-based Pattern Authentication(PPA)system for Internet of Things(IoT)devices that does not require a server to maintain a static password of the login *** server stores user’s information,which they provide at the time of registration,i.e.,the R-code and the symbol,but the P-code,i.e.,the actual password,will change with every login attempt of *** this scheme,users may draw a pattern on the basis of calculation from the P-code and Rcode in the PPA pattern,and can authenticate themselves using their touch dynamic behaviors through Artificial Neural Network(ANN).The ANN is trained on touch behaviors of legitimate users reporting superior performance over the existing *** experimental purposes,PPA is implemented as a prototype on a computer system to carry out experiments for the evaluation in terms of memorability and *** experiments show that the system has an effect of 5.03%of the False Rejection Rate(FRR)and 4.36%of the False Acceptance Rate(FAR),respectively.

关键词： Implicit authentication behavioral authentication artificial neural network processed pattern authentication

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Response of Wheat to Tillage Plus Rice Residue and Nitrogen Management in Rice-Wheat System

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Journal of Integrative Agriculture 2014年第11期13卷 2389-2398页

作者： Khalid Usman Ejaz Ahmad Khan Niamatullah Khan Abdur Rashid Fazal Yazdan Saleem ud din Department of Agronomy Faculty of Agriculture Gomal UniversityD. I. Khan 29050 Pakistan Cotton Research Station Ratta KulachiD. I. Khan 29050 Pakistan Arid Zone Research Institute Ratta KulachiD. I. Khan 29050 Pakistan Oil Seed Research Program National Agricultural Research CentreIslamabad 44000Pakistan

Zero tillage with residues retention and optimizing nitrogen fertilization are important strategies to improve soil quality and wheat （Triticum aestivum L.） yield in rice （Oryza sativa L.）-wheat system. Field experiments were conducted on silty clay soil （Hyperthermic, and Typic Torrilfuvents） in D. I. Khan, Pakistan, to explore the impact of six tillage methods （zero tillage straw retained （ZTsr）, ZT straw burnt （ZTsb）, reduced tillage straw incorporated （RTsi, including tiller and rotavator）, RT straw burnt （RTsb）, conventional tillage straw incorporated （CTsi, including disc plow, tiller, rotavator, and leveling operations）, CT straw burnt （CTsb）） and ifve nitrogen rates, i.e., 0, 100, 150, 200, and 250 kg ha-1 on wheat yield. Mean values for N revealed that spikes m-2, grains/spike, 1 000-grain weight （g）, and grain yield （kg ha-1） were signiifcantly higher at 200 kg N ha-1 in both the years as well as mean over years than all other treatments. Mean values for tillage revealed that ZTsr produced highest number of spikes m-2 among tillage methods. However, grains/spike, 1 000-grain weight, and grain yield were higher in tillage methods with either straw retained/incorporated than tillage methods with straw burnt. Interaction effects were signiifcant in year 1 and in mean over years regarding spikes m-2, 1 000-grain weight, total soil organic matter （SOM）, and total soil N （TSN）. ZTsr produced the most spikes m-2 and 1 000-grain weight at 200 kg N ha-1. ZTsr also produced higher SOM and TSN at 200-250 kg N ha-1 at the end of 2 yr cropping. Thus ZTsr with 200 kg N ha-1 may be an optimum and sustainable approach to enhance wheat yield and soil quality in rice-wheat system.

关键词： wheat yield tillage nitrogen TSN SOM

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Short Response of Spring Wheat to Tillage, Residue Management and Split Nitrogen Application in a Rice-Wheat System

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Journal of Integrative Agriculture 2014年第12期13卷 2625-2633页

作者： Khalid Usman Ejaz Ahmad Khan Fazal Yazdan Niamatullah Khan Abdur Rashid Saleem ud din Department of Agronomy Faculty of Agriculture Gomal UniversityD. I. Khan 29050 Pakistan Oil Seed Research Programme National Agricultural Research Center (NARC) Cotton Research Station Ratta Kulachi D. I. Khan 29050 Pakistan Arid Zone Research Institute Ratta Kulachi D. I. Khan 29050 Pakistan

A ifeld experiment was conducted to study the impact of tillage, crop residue management and nitrogen （N） splitting on spring wheat （Triticum aestivum L.） yield over 2 yr （2010-2012） in a rice （Oryza sativa L.）-wheat system in northwestern Pakistan. The experiment was conducted as split plot arranged in randomized complete blocks design with three replications. Treatments comprised six tillage and residue managements：zero tillage straw retained （ZTsr）, zero tillage straw burnt （ZTsb）, reduced tillage straw incorporated （RTsi）, reduced tillage straw burnt （RTsb）, conventional tillage straw incorporated （CTsi）, and conventional tillage straw burnt （CTsb） as main plots and N （200 kg ha-1） was applied as split form viz., control （no nitrogen＆no splitting, N0S0）;2 splits of total N, half at sowing and half at the 1st irrigation （i.e., 20 d after sowing （DAS））（NS1）;3 splits of total N, 1/3 at sowing, 1/3 at the 1st irrigation, and 1/3 at the 2nd irrigation （NS2）;4 splits of total N, 1/4 at sowing, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation （45 DAS）, and 1/4 at the 3rd irrigation （70 DAS）（NS3）;and 4 splits of total N, 1/4 at the 1st irrigation, 1/4 at the 2nd irrigation, 1/4 at the 3rd irrigation, and 1/4 at the 4th irrigation （95DAS）（NS4） as sub plots. The results showed that the most pikes m-2, grains/spike, 1 000-grain weight, grain yield, and N use efifciency （NUE） were obtained at zero tillage, straw retained and 4 splits application of total N （i.e., at sowing 20, 45 and 70 d after sowing）. The results indicated that ZTsr with application of 200 kg N ha-1 in 4 equal splits viz. at sowing 20, 45 and 70 d after sowing is an appropriate strategy that enhanced wheat yield （7 436-7 634 kg ha-1） and N efifciency （28.6-29.5 kg kg-1） in rice-wheat system.

关键词： tillage residue management N split application wheat yield

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Context-Aware Collaborative Filtering Framework for Rating Prediction Based on Novel Similarity Estimation

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Computers, Materials & Continua 2020年第5期63卷 1065-1078页

作者： Waqar Ali Salah ud din Abdullah Aman Khan Saifullah Tumrani Xiaochen Wang Jie Shao School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China Faculty of Information Technology The University of LahoreLahore54000Pakistan Sichuan Artificial Intelligence Research Institute Yibin644000China

Recommender systems are rapidly transforming the digital world into intelligent information *** valuable context information associated with the users’prior transactions has played a vital role in determining the user preferences for items or rating *** has been a hot research topic in collaborative filtering-based recommender systems for the last two *** paper presents a novel Context Based Rating Prediction(CBRP)model with a unique similarity scoring estimation *** proposed algorithm computes a context score for each candidate user to construct a similarity pool for the given subject user-item pair and intuitively choose the highly influential users to forecast the item *** context scoring strategy has an inherent capability to incorporate multiple conditional factors to filter down the most relevant *** with traditional similarity estimation methods,CBRP makes it possible for the full use of neighboring collaborators’choice on various *** conduct experiments on three publicly available datasets to evaluate our proposed method with random user-item pairs and got considerable improvement in prediction accuracy over the standard evaluation ***,we evaluate prediction accuracy for every user-item pair in the system and the results show that our proposed framework has outperformed existing methods.

关键词： Recommender system context-based similarity estimation rating prediction collaborative filtering

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Numerical Investigation & Comparison of a Tandem-Bladed Turbocharger Centrifugal Compressor Stage with Conventional Design

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Journal of Thermal Science 2014年第6期23卷 523-534页

作者： Syed Noman Danish Shafiq Rehman Qureshi Abdelrahman EL-Leathy Salah ud-din Khan Usama Umer Ma Chaochen Sustainable Energy Technologies Center King Saud University National University of Sciences and Technology PNS JauharKarachiPakistan Mechanical Engineering Department King Saud University FARCAMT Advanced Manufacturing InstituteKing Saud University Beijing Institute of Technology

Extensive numerical investigations of the performance and flow structure in an unshrouded tandem-bladed centrifugal compressor are presented in comparison to a conventional *** characteristics are explored for various tip clearance levels,axial spacings and circumferential *** impeller was modified to tandem-bladed design with no modifications in backsweep angle,meridional gas passage and camber distributions in order to have a true comparison with conventional *** degradation is observed for both the conventional and tandem designs with increase in tip ***-equation models for correlating stage characteristics with tip clearance are *** two designs,it is clearly evident that the conventional design shows better performance at moderate flow ***;near choke flow,tandem design gives better results primarily because of the increase in throat *** point flow rate also seems to drop for tandem compressor resulting in increased range of operation.

关键词： tandem blade conventional compressor inducer exducer numerical simulation

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AI-Driven Pattern Recognition in Medicinal Plants: A Comprehensive Review and Comparative Analysis

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Computers, Materials & Continua 2024年第11期81卷 2077-2131页

作者： Mohd Asif Hajam Tasleem Arif Akib Mohi ud din Khanday Mudasir Ahmad Wani Muhammad Asim Department of Information Technology Baba Ghulam Shah Badshah UniversityRajouriJammu and Kashmir185234India Department of Computer Science Samarkand International University of TechnologySamarkand141500Uzbekistan EIAS Data Science Lab College of Computer and Information SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia

The pharmaceutical industry increasingly values medicinal plants due to their perceived safety and costeffectiveness compared to modern *** the extensive history of medicinal plant usage,various plant parts,including flowers,leaves,and roots,have been acknowledged for their healing properties and employed in plant *** images,however,stand out as the preferred and easily accessible source of *** plant identification by plant taxonomists is intricate,time-consuming,and prone to errors,relying heavily on human *** intelligence(AI)techniques offer a solution by automating plant recognition *** study thoroughly examines cutting-edge AI approaches for leaf image-based plant identification,drawing insights from literature across renowned *** paper critically summarizes relevant literature based on AI algorithms,extracted features,and results ***,it analyzes extensively used datasets in automated plant classification *** also offers deep insights into implemented techniques and methods employed for medicinal plant ***,this rigorous review study discusses opportunities and challenges in employing these AI-based ***,in-depth statistical findings and lessons learned from this survey are highlighted with novel research areas with the aim of offering insights to the readers and motivating new research *** review is expected to serve as a foundational resource for future researchers in the field of AI-based identification of medicinal plants.

关键词： Pattern recognition artificial intelligence machine learning deep learning image processing plant leaf identification

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