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Comparative elemental,mineral and microscopic investigation of sandstone matrix acidizing at HPHT conditions

Petroleum Research 2022年第4期7卷 448-458页

作者： Mian Umer Shafiq Hisham Khaled Ben Mahmud Lei Wang Khizar Abid Sophia nawaz Gishkori NFC Institute of Engineering and Technology MultanPakistan Petroleum Engineering Department Faculty of Engineering and ScienceCurtin University MalaysiaCDT 250Sarawak98009Malaysia Energy and Environmental Research Cluster Faculty of Engineering and ScienceCurtin University MalaysiaCDT 250Sarawak98009Malaysia Petroleum Engineering Department Nazarbayev UniversityKazakhstan University of Gujrat Pakistan

Matrix acidizing is usually conducted on sandstone reservoirs to increase hydrocarbon *** plays an important role in designing acidizing treatments to enhance the production of oil and gas from sandstone *** most common acid in practice to acidize sandstone formation is mud acid after the pre-flush acid *** main aim of the pre-flush acid stage is to dissolve positive ions like calcium,potassium,sodium,etc,which can cause precipitation reactions during the mud acid *** research is aimed to investigate the reaction mechanism of a new pre-flush acid combination(hydrochloric acid and acetic acid)with sandstone *** flooding experiments were performed to react acid with the core samples(6 in×1.5 in)under high pressure and temperature(HPHT)condi-tions(80℃and 1000 psia).Analytical techniques such as Tescan Integrated Mineral Analysis(TIMA)have been used to illustrate the effect of these acids on sandstone *** analysis showed that the new acid combination was effective in dissolving various minerals(ankerite,magnetite)and cations(calcium,magnesium,sodium,and iron).15%HCl proved to be more effective in the dissolution of different particles from sandstone core *** dissolved 32.8%of the initial number of particles present inside the sample while the dissolving power of 5%CH_(3)COOH:10%HCl is 26.7%.Subsequently,the number of pores increased by the application of 15%HCl is 22%while that by 5%CH_(3)COOH:10%HCl is 21.8%.Density analysis showed that both acid combinations removed heavy particles effectively,whereas 5%CH_(3)COOH:10%HCl proved more efficient in dissolving calcium ions which is very important for pre-flush acidizing.

关键词： Mineralogy Sandstone HPHT Core flooding TIMA Hydrochloric acid

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Risk-aware Distributed Optimal Power Flow in Coordinated Transmission and Distribution System

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 502-515页

作者： Aamir nawaz Hongtao Wang Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250000China

Active distribution grids cause bi-directional power flow between transmission system(TS)and distribution system(DS),which not only affects the optimal cost but also the secure operation of the power *** paper proposes a hybrid coordination method to solve the risk-aware distributed optimal power flow(RA-DOPF)problem in coordinated TS and *** operation risk evaluation,the weather-based contingencies are considered in both TS and DS.A hybrid coordination method is developed that entails analytical target cascading(ATC)and Benders decomposition(BD).Moreover,the risk-aware optimal power flow(RAOPF)in TS and risk-based security-constrained optimal power flow in DS have been performed using the BD method considering basic optimal power flow as a master problem,whereas N-1 and N-2 contingencies are considered as *** case studies are performed using the IEEE 30-bus system with generation reserves as a TS and a 13-bus system as a *** results demonstrate the efficacy of the proposed method.

关键词： Analytical target cascading Benders decomposition distribution system preventive and corrective contingen-cies risk awareness transmission system

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A Secure Communication Protocol for Unmanned Aerial Vehicles

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Computers, Materials & Continua 2022年第1期70卷 601-618页

作者： Navid Ali Khan N.Z.Jhanjhi Sarfraz nawaz Brohi Abdulwahab Ali Almazroi Abdulaleem Ali Almazroi School of Computer Science and Engineering(SCE) Taylor’s University Lake-side CampusSubang Jaya47500Malaysia School of Information and Technology Monash UniversityMalaysia University of Jeddah College of Computing and Information Technology at KhulaisDepartment of Information TechnologyJeddahSaudi Arabia Department of Computer Science Rafha Community CollegeNorthern Border UniversityArar91431Saudi Arabia

Mavlink is a lightweight and most widely used open-source communication protocol used for Unmanned Aerial *** UAVs and autopilot systems support it,and it provides bi-directional communication between the UAV and Ground Control *** communications contain critical information about the UAV status and basic control commands sent from GCS to UAV and UAV to *** order to increase the transfer speed and efficiency,the Mavlink does not encrypt the *** a result,the protocol is vulnerable to various security attacks such as Eavesdropping,GPS Spoofing,and *** this study,we tackle the problem and secure the Mavlink communication *** leveraging the Mavlink packet’s vulnerabilities,this research work introduces an experiment in which,first,the Mavlink packets are compromised in terms of security requirements based on our threat *** results show that the protocol is insecure and the attacks carried out are *** overcomeMavlink security,an additional security layer is added to encrypt and secure the *** encryption technique is proposed that makes the communication between the UAV and GCS *** results show that the Mavlink packets are encrypted using our technique without affecting the performance and *** results are validated in terms of transfer speed,performance,and efficiency compared to the literature solutions such as MAVSec and benchmarked with the original Mavlink *** achieved results have significant improvement over the literature and Mavlink in terms of security.

关键词： Unmanned aerial vehicles mavlink protocol drones security UAVs communication

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Dual-active-site Fe/Cu single-atom nanozymes with multifunctional specific peroxidase-like properties for S^(2-)detection and dye degradation

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Chinese Chemical Letters 2023年第6期34卷 267-272页

作者： Xiaofang Chen Ya Wang Min Feng Die Deng Xiaoyi Xie Caixia Deng Kashif nawaz Khattak Xiupei Yang College of Chemistry and Chemical Engineering Chemical Synthesis and Pollution Control Key Laboratory of Sichuan ProvinceChina West Normal UniversityNanchong 637000China College of Environmental Science and Engineering China West Normal UniversityNanchong 637000China

Designing single-atom nanozymes with densely exposed metal atom active sites and enhancing catalytic activity to detect pollutants remain a serious ***,we reported a single-atom nanozyme with layered stacked Fe/Cu dual active sites(Fe/Cu-NC SAzyme)synthesized via hydrothermal and hightemperature pyrolysis using folic acid as a *** with Fe-NC and Cu-NC SAzyme,Fe/Cu-NC SAzyme has higher peroxidase-like activity,which indicates that the doping of synthesized Fe/Cu bimetals can improve the catalytic activity and that the atomic loading of Fe and Cu in Fe/Cu-NC is 5.5 wt%and 2.27 wt%,*** S^(2-)is added to the Fe/Cu-NC catalytic system,a high-sensitivity and high-selectivity S^(2-)colorimetric sensing platform can be established,with a wide linear range(0.09-6μmol/L)and a low detection limit(30 nmol/L),which can be used to detect S^(2-)in environmental water ***’s more,the Fe/Cu-NC SAzyme can activate peroxymonosulfate(PMS)to degrade 99.9%of rhodamine B(Rh B)within 10 min with a degradation kinetics of 0.5943 min^(-1).This work details attractive applications in Fe/Cu-NC SAzyme colorimetric sensing and dye degradation.

关键词： Single-atom nanozymes Dual active sites Peroxidase-like catalyst Colorimetric detection Dye degradation

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Detecting and Mitigating DDOS Attacks in SDNs Using Deep Neural Network

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Computers, Materials & Continua 2023年第11期77卷 2157-2178页

作者： Gul nawaz Muhammad Junaid Adnan Akhunzada Abdullah Gani Shamyla nawazish Asim Yaqub Adeel Ahmed Huma Ajab Department of Information Technology The University of HaripurHaripur22060Pakistan Faculty of Computing and Informatics University Malaysia SabahSabah88400Malaysia Department of Environmental Sciences COMSATS University Abbottabad CampusAbbottabad22010Pakistan Department of Chemistry COMSATS University Abbottabad CampusAbbottabad22010Pakistan

Distributed denial of service(DDoS)attack is the most common attack that obstructs a network and makes it unavailable for a legitimate *** proposed a deep neural network(DNN)model for the detection of DDoS attacks in the Software-Defined Networking(SDN)*** centralizes the control plane and separates it from the data *** simplifies a network and eliminates vendor specification of a *** of this open nature and centralized control,SDN can easily become a victim of DDoS *** proposed a supervised Developed Deep Neural Network(DDNN)model that can classify the DDoS attack traffic and legitimate *** Developed Deep Neural Network(DDNN)model takes a large number of feature values as compared to previously proposed Machine Learning(ML)*** proposed DNN model scans the data to find the correlated features and delivers high-quality *** model enhances the security of SDN and has better accuracy as compared to previously proposed *** choose the latest state-of-the-art dataset which consists of many novel attacks and overcomes all the shortcomings and limitations of the existing *** model results in a high accuracy rate of 99.76%with a low false-positive rate and 0.065%low loss *** accuracy increases to 99.80%as we increase the number of epochs to 100 *** proposed model classifies anomalous and normal traffic more accurately as compared to the previously proposed *** can handle a huge amount of structured and unstructured data and can easily solve complex problems.

关键词： Distributed denial of service(DDoS)attacks software-defined networking(SDN) classification deep neural network(DNN)

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Identification of Anomaly Scenes in Videos Using Graph Neural Networks

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Computers, Materials & Continua 2023年第3期74卷 5417-5430页

作者： Khalid Masood Mahmoud M.Al-Sakhnini Waqas nawaz Tauqeer Faiz Abdul Salam Mohammad Hamza Kashif Department of Software Engineering Lahore Garrison UniversityLahore54000Pakistan School of Business Skyline University CollegeSharjahUAE Al-Madinah International University–Faculty of Computer and Information Technology Kuala LumpurMalaysia College of Computer and Information Systems Islamic University of MadinahMadinahKingdom of Saudi Arabia School of IT Skyline University CollegeSharjahUAE Faculty of Engineering Computing and Science(FECS)-Swinburne University of TechnologySarawak Department of General Education Skyline University CollegeUniversity City of SharjahUAE Department of Computer Science Lahore Garrison UniversityLahore54000Pakistan

Generally,conventional methods for anomaly detection rely on clustering,proximity,or *** themassive growth in surveillance videos,outliers or anomalies find ingenious ways to obscure themselves in the network and make conventional techniques *** research explores the structure of Graph neural networks(GNNs)that generalize deep learning frameworks to graph-structured *** node in the graph structure is labeled and anomalies,represented by unlabeled nodes,are predicted by performing random walks on the node-based graph *** to their strong learning abilities,GNNs gained popularity in various domains such as natural language processing,social network analytics and *** detection is a challenging task in computer vision but the proposed algorithm using GNNs efficiently performs the identification of *** Graph-based deep learning networks are designed to predict unknown objects and *** our case,they detect unusual objects in the form of malicious *** edges between nodes represent a relationship of nodes among each *** case of anomaly,such as the bike rider in Pedestrians data,the rider node has a negative value for the edge and it is identified as an *** encoding and decoding layers are crucial for determining how statistical measurements affect anomaly identification and for correcting the graph path to the best possible *** show that the proposed framework is a step ahead of the traditional approaches in detecting unusual activities,which shows a huge potential in automatically monitoring surveillance *** autonomous monitoring of CCTV,crime control and damage or destruction by a group of people or crowd can be identified and alarms may be triggered in unusual activities in streets or public *** suggested GNN model improves accuracy by 4%for the Pedestrian 2 dataset and 12%for the Pedestrian 1 dataset compared to a few state-of the-art techniq

关键词： Graph neural network deep learning anomaly detection auto encoders

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Text Augmentation-Based Model for Emotion Recognition Using Transformers

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Computers, Materials & Continua 2023年第9期76卷 3523-3547页

作者： Fida Mohammad Mukhtaj Khan Safdar nawaz Khan Marwat Naveed Jan Neelam Gohar Muhammad Bilal Amal Al-Rasheed Department of Computer Science The University of HaripurHaripur22620Pakistan Department of Computer Systems Engineering Faculty of Electrical and Computer EngineeringUniversity of Engineering and Technology PeshawarPeshawar25120Pakistan Department of Electronics Engineering Technology University of TechnologyNowshera24100Pakistan Department of Computer Science Shaheed Benazir BhuttoWomen UniversityPeshawar25000Pakistan Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia

Emotion Recognition in Conversations(ERC)is fundamental in creating emotionally ***-BasedNetwork(GBN)models have gained popularity in detecting conversational contexts for ERC ***,their limited ability to collect and acquire contextual information hinders their *** propose a Text Augmentation-based computational model for recognizing emotions using transformers(TA-MERT)to address *** proposed model uses the Multimodal Emotion Lines Dataset(MELD),which ensures a balanced representation for recognizing human *** used text augmentation techniques to producemore training data,improving the proposed model’s *** encoders train the deep neural network(DNN)model,especially Bidirectional Encoder(BE)representations that capture both forward and backward contextual *** integration improves the accuracy and robustness of the proposed ***,we present a method for balancing the training dataset by creating enhanced samples from the original *** balancing the dataset across all emotion categories,we can lessen the adverse effects of data imbalance on the accuracy of the proposed *** results on the MELD dataset show that TA-MERT outperforms earlier methods,achieving a weighted F1 score of 62.60%and an accuracy of 64.36%.Overall,the proposed TA-MERT model solves the GBN models’weaknesses in obtaining contextual data for ***-MERT model recognizes human emotions more accurately by employing text augmentation and transformer-based *** balanced dataset and the additional training samples also enhance its *** findings highlight the significance of transformer-based approaches for special emotion recognition in conversations.

关键词： Emotion recognition in conversation graph-based network text augmentation-basedmodel multimodal emotion lines dataset bidirectional encoder representation for transformer

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Enhanced catalytic complete oxidation of 1,2-dichloroethane over mesoporous transition metal-doped γ-Al_2O_3

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Journal of Environmental Sciences 2015年第3期27卷 199-209页

作者： Abbas Khaleel Muhammad nawaz Department of Chemistry United Arab Emirates University

High-surface-area mesoprous powders of γ-Al2O3 doped with Cu^2＋, Cr^3＋, and V^3＋ ions were prepared uia a modified sol-gel method and were investigated as catalysts for the oxidation of chlorinated organic compounds. The composites retained high surface areas and pore volumes comparable with those of undoped γ-Al2O3 and the presence of the transition metal ions enhanced their surface acidic properties. The catalytic activity of the prepared catalysts in the oxidation of 1,2-dichloroethane （DCE） was studied in the temperature range of 250-400℃. The catalytic activity and product selectivity were strongly dependent on the presence and the type of dopant ion. While Cu^2＋- and Cr^3＋-containing catalysts showed 100% conversion at 300℃ and 350℃, V3＋-containing catalyst showed considerably lower conversion. Furthermore, while the major products of the reactions over γ-alumina were vinyl chloride （C2H3Cl） and hydrogen chloride （HCl） at all temperatures, Cu- and Cr-doped catalysts showed siguiticantly stronger capability for deep oxidation to CO2.

关键词： Chlorinated organic compounds Catalytic oxidation Sol-gel method Mixed metal oxides

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Adaptive Multi-Cost Routing Protocol to Enhance Lifetime for Wireless Body Area Network

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Computers, Materials & Continua 2022年第7期72卷 1089-1103页

作者： Muhammad Mateen Yaqoob Waqar Khurshid Leo Liu Syed Zulqarnain Arif Imran Ali Khan Osman Khalid Raheel nawaz Department of Computer Science COMSATS University IslamabadAbbottabad Campus22060Pakistan Department of OTEHM Manchester Metropolitan UniversityManchesterUK

Wireless Body Area Network(WBAN)technologies are emerging with extensive applications in several *** is a fascinating domain of WBAN for smart monitoring of a patient’s *** important factor to consider in WBAN is a node’s *** the lifetime of nodes is critical to address many issues,such as utility and *** routing protocols have addressed the energy conservation problem but considered only a few parameters,thus affecting their ***,most of the existing schemes did not consider traffic prioritization which is critical in *** this paper,an adaptive multi-cost routing protocol is proposed with a multi-objective cost function considering minimum distance from sink,temperature of sensor nodes,priority of sensed data,and maximum residual energy on sensor *** performance of the proposed protocol is compared with the existing schemes for the parameters:network lifetime,stability period,throughput,energy consumption,and path *** is evident from the obtained results that the proposed protocol improves network lifetime and stability period by 30%and 15%,respectively,as well as outperforms the existing protocols in terms of throughput,energy consumption,and path loss.

关键词： Multi-cost routing protocol network lifetime wireless body area network adaptive routing residual energy clustering poisson distribution

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The correlation of spot urinary protein-to-creatinine ratio with 24-h urinary protein excretion in various glomerulopathies

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World Journal of Nephrology 2023年第5期12卷 159-167页

作者： Amber Raza Syed Haider nawaz Rahma Rashid Ejaz Ahmed Muhammed Mubarak Department of Nephrology Sindh Institute of Urology and TransplantationSindhKarachi 74200Pakistan Department of Pathology Sindh Institute of Urology and TransplantationSindhKarachi 74200Pakistan

BACKGROUND Proteinuria is an important and well-known biomarker of many forms of kidney *** quantitation is of particular importance in the diagnosis and management of glomerular *** quantification can be done by several *** these,the measurement of 24-h urinary protein excretion is the gold standard ***,it is cumbersome,time-consuming,and inconvenient for patients and is not completely *** alternative methods have been tested over time albeit with conflicting *** the latter,the measurement of urine protein-to-creatinine ratio(uPCR)in singlevoided urinary samples is widely *** majority of studies found a good correlation between uPCR in single urine samples with 24-h urinary protein estimation,whereas others did *** To investigate the correlation of spot uPCR with 24-h urinary protein estimation in patients suffering from different forms of glomerulopathies at a single largevolume nephrological center in *** This cross-sectional,observational study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan from September 2017 to March *** newly presenting adult patients with proteinuria who were being investigated for suspected glomerulonephritis and persistent proteinuria with ages between 18 to 60 years were *** patients were given detailed advice regarding 24-h urine collection starting at 7:00 AM for total protein and creatinine excretion estimations.A spot urine sample was collected the next day at the time of submission of a 24-h urine sample for measuring uPCR along with a blood *** data of patients were collected in a *** version 20.0 was used for statistical *** A total of 157 patients were *** mean age was 30.45±12.11 *** were 94(59.8%)males and 63(40.2%)*** mean 24-h urinary protein excretion was 3192.78±1959.79 mg and the mean spot uPCR was 3.16±1.52 in al

关键词： Glomerulopathies 24-h proteinuria Spot urinary protein-to-creatinine ratio Correlation Proteinuria Agreement

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