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Chinese Optics Letters 2024年第6期22卷 182-190页

作者： Zhipeng Ding Wei Su Lipeng’an Ye Yuanhang Zhou Wenlong Li riaz ali Bin Tang Hongbing Yao College of Mechanics and Engineering Science Hohai UniversityNanjing 211100China School of Microelectronics and Control Engineering Changzhou UniversityChangzhou 213164China

In this work, we propose a novel approach that combines a bidirectional deep neural network(BDNN) with a multifunctional metasurface absorber(MMA) for inverse design, which can effectively address the challenge of on-demand customization for absorbers. The inverse design of absorption peak frequencies can be achieved from 0.5 to 10 terahertz(THz), covering the quasi-entire THz band. Based on this, the BDNN is extended to broadband absorption, and the inverse design yields an MMA at the desired frequency. This work provides a broadly applicable approach to the custom design of multifunctional devices that can facilitate the evaluation and design of metasurfaces in electromagnetic absorption.

关键词： terahertz inverse design bidirectional deep neural network metasurface

VMR:Virtual Machine Replacement Algorithm for QoS and Energy Efficiency in Cloud Data Centers

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VMR:Virtual Machine Replacement Algorithm for QoS and Energy...

作者： riaz ali 上海交通大学

学位级别：硕士

The Cloud computing paradigm facilitates customers to have on demand access to cloud *** leads to a large amount of physical machines and data centers in order to satisfy the requirements of customers,which are constantly on the *** progress in the quantity of running physical machines is directly proportionate to the rise in the energy ***,saving of energy utilization has become one of the foremost challenges of Cloud data *** minimize the energy consumption,a new technique with an adaptive threshold virtual machine replacement（VMR）algorithm that decreases the number of active physical machines in the Cloud data center was *** scheme is being broadly applied across Information Technology infrastructure owing to its many benefits such as efficient resource utilization,ease of management,minimized energy *** machine is the basic unit of scheduling for saving energy consumption in Cloud data *** replacement algorithm expands the performance of the whole system by efficiently balancing the load through physical *** is an important feature for Cloud computing data centers that has recently attracted considerable *** consumption is not measured in most of the migration *** our thesis,we design a novel energy efficient approach that aims to minimize the energy consumption without reducing the Quality of Service（QoS）for users deadline requirements in Cloud data *** also propose a VM replacement algorithm for QoS and energyawareness in cloud data *** experimentally match the performance of our algorithm with other advanced algorithms（i.e.,the random algorithm and the first-fit algorithm）.The experimental results illustrate that our solution improves first fit and random algorithms by twice and four times respectively,and is also energy efficient with reliable QoS while ensuring high level of Service Level Agreement（SLA）.

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Elevating Image Steganography:A Fusion of MSB Matching and LSB Substitution for Enhanced Concealment Capabilities

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Computers, Materials & Continua 2024年第5期79卷 2923-2943页

作者： Muhammad Zaman ali Omer riaz Hafiz Muhammad Hasnain Waqas Sharif Tenvir ali Gyu Sang Choi Department of Information Technology The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Computer Science The Islamia University of BahawalpurBahawalpur63100Pakistan School of Computer Science and Engineering Yeungnam UniversityGyeongbuk38541Korea

In today’s rapidly evolving landscape of communication technologies,ensuring the secure delivery of sensitive data has become an essential *** overcome these difficulties,different steganography and data encryption methods have been proposed by researchers to secure *** of the proposed steganography techniques achieve higher embedding capacities without compromising visual imperceptibility using LSB *** this work,we have an approach that utilizes a combinationofMost SignificantBit(MSB)matching andLeast Significant Bit(LSB)*** proposed algorithm divides confidential messages into pairs of bits and connects them with the MSBs of individual pixels using pair matching,enabling the storage of 6 bits in one pixel by modifying a maximum of three *** proposed technique is evaluated using embedding capacity and Peak Signal-to-Noise Ratio(PSNR)score,we compared our work with the Zakariya scheme the results showed a significant increase in data concealment *** achieved results of ourwork showthat our algorithmdemonstrates an improvement in hiding capacity from11%to 22%for different data samples while maintaining a minimumPeak Signal-to-Noise Ratio(PSNR)of 37 *** findings highlight the effectiveness and trustworthiness of the proposed algorithm in securing the communication process and maintaining visual integrity.

关键词： Steganography most significant bit(MSB) least significant bit(LSB) peak signal-to-noise ratio(PSNR)

An Innovative Approach Using TKN-Cryptology for Identifying the Replay Assault

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Computers, Materials & Continua 2024年第1期78卷 589-616页

作者： Syeda Wajiha Zahra Muhammad Nadeem ali Arshad Saman riaz Muhammad Abu Bakr Ashit Kumar Dutta Zaid Alzaid Badr Almutairi Sultan Almotairi Department of Computer Science Alhamd Islamic UniversityIslamabad44000Pakistan Department of Computer Science and Technology University of Science and Technology BeijingBeijing100083China Department of Computer Science National University of TechnologyIslamabad44000Pakistan Department of Electrical Engineering National University of TechnologyIslamabad44000Pakistan Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityRiyadh13713Saudi Arabia Department of Computer Science Faculty of Computer and Information SystemsIslamic University of MadinahMedinah42351Saudi Arabia Department of Information Technology College of Computer Sciences and Information Technology CollegeMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Natural and Applied Sciences Faculty of Community CollegeMajmaah UniversityMajmaah11952Saudi Arabia

Various organizations store data online rather than on physical *** the number of user’s data stored in cloud servers increases,the attack rate to access data from cloud servers also *** researchers worked on different algorithms to protect cloud data from replay *** of the papers used a technique that simultaneously detects a full-message and partial-message replay *** study presents the development of a TKN(Text,Key and Name)cryptographic algorithm aimed at protecting data from replay *** program employs distinct ways to encrypt plain text[P],a user-defined Key[K],and a Secret Code[N].The novelty of the TKN cryptographic algorithm is that the bit value of each text is linked to another value with the help of the proposed algorithm,and the length of the cipher text obtained is twice the length of the original *** the scenario that an attacker executes a replay attack on the cloud server,engages in cryptanalysis,or manipulates any data,it will result in automated modification of all associated values inside the *** mechanism has the benefit of enhancing the detectability of replay ***,the attacker cannot access data not included in any of the papers,regardless of how effective the attack strategy *** the end of paper,the proposed algorithm’s novelty will be compared with different algorithms,and it will be discussed how far the proposed algorithm is better than all other algorithms.

关键词： Replay attack malware message attack file encryption cryptology data security

Numerical Investigations on Supercritical Heat Transfer Characteristics of Environmental Friendly Refrigerants

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International Journal of Clean Coal and Energy 2021年第2期10卷 21-40页

作者： Adnan Ibrahim Peng Hu Yiran Jiang ali riaz Farrukh Saleem Yifang Dong Lei Jia Panpan Zhao Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei China Department of Mechanical Engineering Pakistan Institute of Engineering and Applied Sciences Islamabad Pakistan School of Engineering Science University of Science and Technology of China Hefei China Hefei General Machinery Research Institute Co. Ltd. Hefei China

The heat transfer of supercritical fluids is a vastly growing field, specifically to find suitable alternatives to replace conventional R134a, which can be beneficial for climate change. Most of the experimental and numerical investigations have been conducted to explore supercritical water, carbon dioxide and R134a as heat transfer working fluids. Hydrofluoroolefin (HFO) and refrigerants blends have been considered the most environment-friendly refrigerants to replace Chlorofluorocarbons (CFCs), Hydrochlorofluoro-carbons (HCFCs) and Hydrofluorocarbons (HFCs). Their main advantage of zero Ozone Depletion Potential (ODP) and comparatively lower Global Warming Potential (GWP) have attracted growing amount of attention to mitigate environmental issues. This work adopts the computational method and takes the environmentally friendly refrigerants to investigate the heat transfer characteristics under widely used shear-stress transport (SST) model. A comprehensive comparison was performed at reduced pressure of 1.10 for supercritical fluids R515A, R1234ze(E) and R134a. The peaks of heat transfer coefficient occurred in the vicinity of pseudo critical temperature for all of these considered fluids;however, R134a resulted in higher heat transfer coefficient, Reynolds number and Prandtl number in comparison with R515A and R1234ze(E). The higher heat transfer coefficient of supercritical fluid R134a is owing to its thermophysical properties and the specific heat plays crucial role in the heat transfer of supercritical fluids. Owing to environmental issues, R515A can be a considerable replacement of R134a. R1234ze(E) is also promising alternative to R134a;however, safety issues should thoroughly concern its mild flammable characteristics.

关键词： Heat Transfer Supercritical Fluids Simulations R515A R1234ze(E) Environmental Friendly Refrigerants

Thermophysical Properties and Supercritical Heat Transfer Characteristics of R515A

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Natural Science 2021年第6期13卷 218-234页

作者： Adnan Ibrahim Peng Hu Yiran Jiang Farrukh Saleem ali riaz Yifang Dong Lei Jia Panpan Zhao Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei China School of Engineering Science University of Science and Technology of China Hefei China Department of Mechanical Engineering Pakistan Institute of Engineering and Applied Sciences Islamabad Pakistan Hefei General Machinery Research Institute Co. Ltd. Hefei China

The heat transfer of supercritical fluids is a vastly growing field, specifically to find suitable alternative to replace conventional R134a, which can be beneficial for climate change. A considerable suggestion is R515A which possesses considerably lower global warming potential. The present simulations are designed to study supercritical fluid R515A under cooling conditions in horizontal position. The effect of pressure, mass flux, heat flux and tube diameter were considered for horizontal tube in the vicinity of pseudo critical temperature. Numerical investigations on heat transfer characteristics of supercritical fluid R515A were performed using widely used shear-stress transport (SST) model. Moreover, heat transfer correlations were developed and suggested to accurately predict Nusselt number within 10% accuracy. The simulation results showed about 3.98% average absolute deviation.

关键词： Environmental Friendly Refrigerant Supercritical Fluid R515A Simulations Heat Transfer Correlations Shear-Stress Transport (SST) Model

Experimentation on Optimal Configuration and Size of Thin Cylinders in Natural Convection

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Semiconductor Science and Information Devices 2022年第2期4卷 17-28页

作者： ali riaz Adnan Ibrahim Muhammad Sohail Bashir Masroor Asghar Muhammad Abdullah Ajmal Shah Department of Mechanical Engineering Pakistan Institute of Engineering and Applied SciencesIslamabad45650Pakistan School of Engineering Science University of Science and Technology of ChinaHefei230027China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter ChemistryDepartment of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui230026China Department of Information Technology University of Southern QueenslandToowoomba4350QueenslandAustralia

In this paper,an experimental study of laminar,steady state natural convection heat transfer from heated thin cylinders in an infinite air medium has been *** electrically heated cylinders having the same slenderness ratio(L/D)i.e.6.1 but different diameters i.e.3.8 cm and 5.08 cm were used.105 experiments were carried out to study the effect of diameter and inclination angle of thin cylinder on natural convection heat *** mandatory corrections of radiation and endcap heat losses,convective heat transfer results were presented in the form of local and average dimensionless *** vertical configuration of thin cylinder,Nusselt number was varied from 52.99 to 95.10 corresponding to 1.28×10^(8)≤Ra*L≤1.08×10^(10).While for horizontal configuration,Nusselt number was varied from 10.74 to 17.78 corresponding to 9.42×10^(4)≤Ra*D≤8.17×10^(6).Results were compared with the published data and found satisfactory as the maximum percentage difference was only 3.09%.The essence of research is that the heat transfer coefficient increases with decrease in diameter and increase in inclination *** flow visualization was done to capture patterns of fluid ***,comparison was made to quantify increase in Nusselt number from slender cylinder as compared to the flat plate.

关键词： Natural convection Thin cylinders Flat plate Nusselt number

Convection Heat Transfer from Heated Thin Cylinders Inside a Ventilated Enclosure

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Semiconductor Science and Information Devices 2022年第2期4卷 10-16页

作者： ali riaz Adnan Ibrahim Muhammad Sohail Bashir Muhammad Abdullah Ajmal Shah Abdul Quddus Department of Mechanical Engineering Pakistan Institute of Engineering and Applied SciencesIslamabad45650Pakistan School of Engineering Science University of Science and Technology of ChinaHefeiAnhui230027China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter ChemistryDepartment of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui230026China

Experimental study was conducted to determine the effect of velocity of axial fan,outlet vent height,position,area,and aspect ratio(h/w)of ventilated enclosure on convection heat *** wooden ventilated enclosure having top and front transparent wall was made up of Perspex for visualization,and internal physical dimensions of box were 200 mm×200 mm×400 *** vent was at bottom while outlet vents were at the side and top *** heated cylindrical heat source having 6.1 slenderness ratio was fabricated and hanged at the centre of the *** calculate heat transfer rates,thermocouples were attached to the inner surface of heat source with silica *** source was operated at constant heat flux in order to quantify the effect of velocity of air on heat *** was observed that average Nusselt number was increased from 68 to 216 by changing velocity from 0 to 3.34 m/s at constant modified Grashof number i.e.5.67E+*** variation in outlet height at the front wall did not affect heat transfer in forced convection ***,Nusselt number decreased to 5%by changing the outlet position from top to the front wall or by 50%reduction in outlet area during forced *** rise in temperature of enclosure increased from 8.19 K to 9.40 K by increasing aspect ratio of enclosure from 1.5 to 2 by operating heat source at constant heat flux i.e.541.20 w/m^(2).

关键词： Experimentation Ventilated enclosures Convection heat transfer Dimensionless data

Effect of fineness of ash on pozzolanic properties and acid resistance of sugarcane bagasse ash replaced cement mortars

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Frontiers of Structural and Civil Engineering 2022年第10期16卷 1287-1300页

作者： Shan E ali Rizwan AZAM Muhammad Rizwan riaz Mohamed ZAWAM Department of Civil Engineering University of Engineering&Technology LahoreLahore 54890Pakistan Faculty of Engineering Cairo UniversityCairo 12613Egypt

This paper addresses the potential use of Sugar Cane Bagasse Ash(SCBA)as a pozzolanic material for partial cement replacement in concrete *** mortars containing SCBA having five different particle size distributions at a replacement rate of 20%by weight were used to study the chemical and physical pozzolanic properties of *** durability of SCBA replaced mortars was also *** with 0%retained on sieve No.325 was used to replace 20%by weight of cement and create mortar specimens that were subjected to sulfuric acid attack of varying concentrations(1%–3%by weight of water).The tested samples were observed to check visual distortion,mass loss,and compressive strength loss at 1,7,14,28,and 56 d of acidic exposure,and the results were compared to those for the control sample,that was lime water cured,at the same *** SCBA sets were found to meet the requirements for pozzolan class N specified by ASTM C *** containing SCBA with 0%or 15%retention produced better compressive strength than the control mortars after 28 ***,X-ray fluorescence and X-ray diffraction analysis showed that the SCBA had favorable chemical properties for a pozzolanic ***,SCBA replaced samples at all ages showed improved resistance against acidic attack relative to that of the control *** deterioration was seen for 3%concentrated *** study’s findings demonstrated that SCBA with an appropriate fineness could be used as a pozzolanic material,consistently with ASTM C 618.

关键词： durability cement replacement sugarcane bagasse ash fineness of ash pozzolanic properties mortar acid resistance

A Levenberg–Marquardt Based Neural Network for Short-Term Load Forecasting

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Computers, Materials & Continua 2023年第4期75卷 1783-1800页

作者： Saqib ali Shazia riaz Safoora Xiangyong Liu Guojun Wang School of Computer Science Guangzhou University Guangzhou510006Guangdong ProvinceChina Department of Computer Science University of AgricultureFaisalabad38000Pakistan Department of Computer Science Government College Women UniversityFaisalabad38000Pakistan

Short-term load forecasting (STLF) is part and parcel of theefficient working of power grid stations. Accurate forecasts help to detect thefault and enhance grid reliability for organizing sufficient energy *** ranges from an hour ahead prediction to a day ahead prediction. Variouselectric load forecasting methods have been used in literature for electricitygeneration planning to meet future load demand. A perfect balance regardinggeneration and utilization is still lacking to avoid extra generation and misusageof electric load. Therefore, this paper utilizes Levenberg–Marquardt(LM) based Artificial Neural Network (ANN) technique to forecast theshort-term electricity load for smart grids in a much better, more precise,and more accurate manner. For proper load forecasting, we take the mostcritical weather parameters along with historical load data in the form of timeseries grouped into seasons, i.e., winter and summer. Further, the presentedmodel deals with each season’s load data by splitting it into weekdays andweekends. The historical load data of three years have been used to forecastweek-ahead and day-ahead load demand after every thirty minutes makingload forecast for a very short period. The proposed model is optimized usingthe Levenberg-Marquardt backpropagation algorithm to achieve results withcomparable statistics. Mean Absolute Percent Error (MAPE), Root MeanSquared Error (RMSE), R2, and R are used to evaluate the model. Comparedwith other recent machine learning-based mechanisms, our model presentsthe best experimental results with MAPE and R2 scores of 1.3 and 0.99,respectively. The results prove that the proposed LM-based ANN modelperforms much better in accuracy and has the lowest error rates as comparedto existing work.

关键词： Short-term load forecasting artificial neural network power generation smart grid Levenberg-Marquardt technique