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Effects of hooked-collar on the local scour around a lenticular bridge pier

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International Journal of Sediment Research 2023年第1期38卷 1-11页

作者： Rashid Farooq Amir Hossein Azimi Muhammad Atiq Ur rehman Tariq Afzal Ahmed Department of Civil Engineering International Islamic University Department of Civil Engineering Lakehead University College of Engineering and Science Victoria University Department of Civil Engineering University of Engineering and Technology James Watt School of Engineering University of Glasgow

This paper presents the results of comprehensive laboratory experiments to investigate the effects of hooked-collar on the scour development around a vertical pier with a lenticular cross section. The flow around the pier was uniform, steady, and under the clear-water condition. The axial scour profiles for cases without and with a lenticular hooked-collar were measured and the effects of hooked-collar dimensions and elevation from the bed were examined. To compute the efficiency of hooked-collar for scour prevention, the results of local scour for a bridge pier without a collar and a bridge pier with a plain collar, without a hooked wall, were used as benchmark data sets. A wide range of hooked-collar geometries such as the ratio of collar width to the pier width, Wc/Wp, ranging from 1.5 to 3.5, the ratio of hooked-collar wall height to the pier width, Hc/Wp, ranging from 0.15 to 0.6, and the ratio of collar elevation to the pier width, Ec/Wp, of-0.5, 0, and 0.5 were tested. The experimental results indicated that the equilibrium scour depth decreased with the ratio of hooked-collar to the pier width when Wcis twice the pier width, Wp. For Wc/Wp> 2, the scour depth was similar to the tests with an infinitely large pier width. In addition, the scour depth consistently reduced as the hooked-collar wall height, Hc, to the pier width, Wp, approached 0.3. The highest scour reduction efficiency was achieved when the hooked-collar being placed on the bed surface. Empirical models were developed for prediction of maximum scour depth near the lenticular bridge pier with a modified collar. The results showed that the volume of scour hole around a lenticular pier increased non-linearly with the maximum scour depth and it was independent of the hooked-collar geometry.

关键词： Local scour Erosion Collar Hooked-collar Lenticular pier Scour countermeasure Steady flow

Trace element geochemistry and stable isotopic(δ^(13)C andδ^(15)N)records of the Paleocene coals,Salt Range,Punjab,Pakistan

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International Journal of Mining Science and Technology 2022年第3期32卷 551-561页

作者： Noshin Masood Tehseen Zafar Karen A.Hudson-Edwards Hafiz U.rehman Abida Farooqi Environmental Geochemistry Laboratory Department of Environmental SciencesFaculty of Biological SciencesQuaid-i-Azam UniversityPO 45320Pakistan Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China Institute of Geology University of the PunjabLahore 54590Pakistan Environment&Sustainability Institute and Camborne School of Mines University of ExeterTR109EZUK Graduate School of Sciences and Engineering Kagoshima UniversityKagoshima 890-0065Japan

The Paleocene coals of the Salt Range in the Punjab Province of Pakistan have great economic potential;however,their trace element and stable isotopic characteristics have not been studied in detail except for a few sporadic *** this study,a total of 59 coal samples of which 14 are obtained from open cast mines have been investigated for elemental composition andδ^(13)C-δ^(15)N isotopic *** contents of trace elements such as Co,Cr,Cu,Pb,Sr,Th,U,V,and Zn are 7.4,41.7,11.2,12.5,90.2,4.0,1.9,128,and 31.1 mg/kg,*** values,when compared with the World Coal Clarke values,were relatively higher in low-rank coals in comparison with Clarke values for brown ***,As(20.4 mg/kg),Co(6.6 mg/kg),Cr(22.4 mg/kg),Cu(^(13).3 mg/kg),Pb(19.2 mg/kg),Sr(^(15)4.7 mg/kg),Th(2.5 mg/kg),V(47.8 mg/kg),and Zn(75.1 mg/kg)were significantly higher in the sub-bituminous to bituminous coals of the Salt *** analysis,based on X-ray diffraction and energy dispersive X-ray spectroscopy,revealed that the studied samples contain illite,kaolinite calcite,gypsum,pyrite,and *** affinity with organic and inorganic phases of coals calculated by an indirect statistical approach indicated a positive association of ash content with Ag,Al,Co,Cr,Cs,Cu,Mn,P,Rb,Pb,Th,U,and V,suggesting the presence of inorganic components in studied ***,As,Fe,Sr,and Zn exhibit negative correlations that imply their association with the organic ***δ^(13)C andδ^(15)N isotopic range and average−24.94‰to−25.86‰(−25.41‰)and−2.77‰to 3.22‰(0.96‰),respectively,reflecting 3C type modern terrestrial vegetation were common in the palaeomires of studied coal *** addition,the trivial variations of 0.92‰and 0.45‰among^(13)C and^(15)N values can be attributed to water level fluctuations and plant assemblies.

关键词： Coal Salt Range Pakistan Geochemistry Trace elements δ^(13)C andδ^(15)N isotopes

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Improved Spallation Resistance of the Oxide Scale by Hf/Y Co-doping in Ni-Based Superalloy at High Temperature

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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1744-1758页

作者： Khalil rehman Naicheng Sheng Shigang Fan Shijie Sun Guicheng Hou Yizhou Zhou Xiaofeng Sun Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Material Science and Engineering University of Science and Technology of ChinaHefei230026China

Ni-based superalloys added with comparably higher concentrations of single-doped Hf and co-doped Hf/Y are prepared by vacuum induction melting(VIM).The oxidation properties up to 300 h at 900℃,1000℃,and 1100℃ are *** undoped alloy exhibited a minimum oxidation rate at 900℃ and 1000℃.The co-doped alloy showed a higher oxidation rate;however,it possesses better scale adhesion,and no spallation ***-doped alloy showed a lower oxidation rate and better scale adhesion at 900℃ and 1000℃,but exhibited a shorter lifetime at 1100℃.The spallation of the Hf-doped alloy is attributed to the precipitation of the HfO2 in and beneath the oxide *** spallation in the undoped alloy is accredited to the thermal expansion mismatch between the growing oxide scale and superalloy *** two reactive elements(REs)in alloy minimized the precipitation of RE oxide in the oxide scale,diminished internal oxidation in the alloy,and decreased oxide scale spallation.

关键词： Superalloys Reactive elements Oxidation kinetics Microstructure Spallation resistance

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Structural and Electronic Properties of Lutetium Doped Germanium Clusters LuGen^((+/0/-))(n=6~19):A Density Functional Theory Investigation

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Chinese Journal of Structural Chemistry 2022年第3期41卷 155-165,I0011页

作者：杨兆峰曹珍珠 Aziz U rehman 杨桔材 School of Chemical Engineering Inner Mongolia University of Technologyand Inner Mongolia Key Laboratory of Theoretical and Computational Chemistry SimulationHohhot 010051China School of Energy and Power Engineering Inner Mongolia University of TechnologyHohhot 010051China

Structural growth mechanism,energetics,and electronic properties of cationic,neutral,and anionic lutetium doped germanium cluster LuGen^((+/0/-))(n=6~19)were comprehensively studied by the ABCluster unbiased global search technique with a hybrid density functional theory *** to the experimental PES,the anion evolution of structure can be clearly defined as four-phase:from the adsorbed to the link structure,then to the half cage motif,and finally to the endohedral *** results revealed that the LuGe16-as Frank-Kasper structure with high symmetry of Td can greatly enhance the *** structures have shown thermodynamic stability and appropriate energy *** materials are suitable *** approaches,including quasi-spherical geometry with closed-shell model,aromaticity,UV-Vis spectra,density of states(DOS)and partial density of states(PDOS)were applied to further support the results.

关键词： lutetium doped germanium clusters the ground state structure density functional theory electronic property

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Data Fusion-Based Machine Learning Architecture for Intrusion Detection

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Computers, Materials & Continua 2022年第2期70卷 3399-3413页

作者： Muhammad Adnan Khan Taher M.Ghazal Sang-Woong Lee Abdur rehman Pattern Recognition and Machine Learning Lab Department of SoftwareGachon UniversitySeongnam13557Korea Center for Cyber Security Faculty of Information Science and TechnologyUniversiti Kebansaan Malaysia(UKM)43600BangiSelangorMalaysia School of Information Technology Skyline University CollegeUniversity City Sharjah1797SharjahUAE School of Computer Science National College of Business Administration&EconomicsLahore54000Pakistan

In recent years,the infrastructure of Wireless Internet of Sensor Networks(WIoSNs)has been more complicated owing to developments in the internet and devices’*** effectively prepare,control,hold and optimize wireless sensor networks,a better assessment needs to be *** field of artificial intelligence has made a great deal of progress with deep learning systems and these techniques have been used for data *** study investigates the methodology of Real Time Sequential Deep Extreme LearningMachine(RTS-DELM)implemented to wireless Internet of Things(IoT)enabled sensor networks for the detection of any intrusion *** fusion is awell-knownmethodology that can be beneficial for the improvement of data accuracy,as well as for the maximizing of wireless sensor networks *** also suggested an approach that not only makes the casting of parallel data fusion network but also render their computations more *** using the Real Time Sequential Deep Extreme Learning Machine(RTSDELM)methodology,an excessive degree of reliability with a minimal error rate of any intrusion activity in wireless sensor networks is *** results show that wireless sensor networks are optimized effectively to monitor and detect any malicious or intrusion activity through this proposed ***,threats and a more general outlook are explored.

关键词： Wireless internet of sensor networks machine learning deep extreme learning machine artificial intelligence data fusion

Detection of Copy-Move Forgery in Digital Images Using Singular Value Decomposition

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Computers, Materials & Continua 2023年第2期74卷 4135-4147页

作者： Zaid Nidhal Khudhair Farhan Mohamed Amjad rehman Tanzila Saba Saeed Ali bahaj Faculty of Engineering School of ComputingUniversity Technology of MalaysiaJohar BahruMalaysia UTM-IRDA MaGICX Institute of Human Centered EngineeringUniversiti Teknologi MalaysiaMalaysia Artificial Intelligence&Data Analytics Lab CCIS Prince Sultan University Riyadh Saudi Arabia Computer Techniques Engineering Department Faculty of Information TechnologyImam Ja’afar Al-Sadiq UniversityBaghdadIraq

This paper presents an improved approach for detecting copy-move forgery based on singular value decomposition(SVD).It is a block-based method where the image is scanned from left to right and top to down by a sliding window with a determined *** each step,the SVD is ***,the diagonal matrix’s maximum value(norm)is selected(representing the scaling factor for SVD and a fixed value for each set of matrix elements even when rotating thematrix or scaled).Then,the similar norms are grouped,and each leading group is separated into many subgroups(elements of each subgroup are neighbors)according to 8-adjacency(the subgroups for each leading group must be far from others by a specific distance).After that,a weight is assigned for each subgroup to classify the image as forgery or ***,the F1 score of the proposed system is measured,reaching 99.1%.This approach is robust against rotation,scaling,noisy images,and illumination *** is compared with other similarmethods and presents very promised results.

关键词： Forgery image forensic image processing region duplication SVD transformation technological development

Finger Vein Authentication Based on Wavelet Scattering Networks

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Computers, Materials & Continua 2022年第8期72卷 3369-3383页

作者： Amjad rehman Majid Harouni Maedeh Omidiravesh Suliman Mohamed Fati Saeed Ali Bahaj Artificial Intelligence&Data Analytics Lab CCIS Prince Sultan UniversityRiyadh11586Saudi Arabia Department of Computer Engineering Dolatabad BranchIslamic Azad UniversityIsfahanIran Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityIsfahanIran MIS Department College of Business Administration Prince Sattam bin Abdulaziz UniversityAlkharj11942Saudi Arabia

Biometric-based authentication systems have attracted more attention than traditional authentication techniques such as passwords in the last two *** biometrics such as fingerprint,palm,iris,palm vein and finger vein and other biometrics have been *** of the challenges in biometrics is physical *** of finger vein is of the biometrics least exposed to physical *** methods have been proposed for authentication with the help of this biometric that suffer from weaknesses such as high computational complexity and low identification *** paper presents a novel method of scattering wavelet-based identity *** wavelet extracts image features from Gabor wavelet filters in a structure similar to convolutional neural *** distinguishes this algorithm from other popular feature extraction methods such as deep learning methods,filter-based methods,statistical methods,etc.,is that this algorithm has very high skill and accuracy in differentiating similar images but belongs to different classes,even when the image is subject to serious damage such as noise,angle changes or pixel location,this descriptor still generates feature vectors in away thatminimizes classifier *** improves classification and *** proposed method has been evaluated using two databases Finger Vein USM(FV-USM)and Homologous Multimodal biometrics Traits(SDUMLA-HMT).In addition to having reasonable computational complexity,it has recorded excellent identification rates in noise,rotation,and transmission *** best,it has a 98.2%identification rate for the SDUMLA-HMT database and a 96.1%identification rate for the FV-USM database.

关键词： Biometrics finger veins wavelet scattering vein authentication disaster risk reduction

Design of Nonlinear Components Over a Mordell Elliptic Curve on Galois Fields

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Computers, Materials & Continua 2022年第4期71卷 1313-1329页

作者： Hafeez ur rehman Tariq Shah Amer Aljaedi Mohammad Mazyad Hazzazi Adel RAlharbi Department of Mathematics Quaid-i-Azam UniversityIslamabadPakistan College of Computing and Information Technology University of TabukTabuk71491Saudi Arabia Department of Mathematics College of ScienceKing Khalid UniversityAbhaSaudi Arabia

Elliptic curve cryptography ensures more safety and reliability than other public key cryptosystems of the same key *** recent years,the use of elliptic curves in public-key cryptography has increased due to their complexity and *** kinds of substitution boxes are proposed to address the substitution process in the cryptosystems,including dynamical,static,and elliptic curve-based ***,elliptic curve-based S-boxes are based on prime field GF(p)but in this manuscript;we propose a new technique of generating S-boxes based on mordell elliptic curves over the Galois field GF(2n).This technique affords a higher number of possibilities to generate S-boxes,which helps to increase the security of the *** robustness of the proposed S-boxes against the well-known algebraic and statistical attacks is analyzed to classify its potential to generate confusion and achieve up to the mark results compared to the various *** majority logic criterion results determine that the proposed S-boxes have up to the mark cryptographic strength.

关键词： Galois field elliptic curve S-box nonlinearity

Geographic distribution of arsenic contamination in the Himalayan Rivers flowing through Pakistan: Implications for its natural source and effects of anthropogenic activities

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International Journal of Sediment Research 2023年第4期38卷 543-555页

作者： Ishtiaque Hussain Hafiz Ur.rehman Takaaki Itai Junaid Ali Khattak Abida Farooqi Environmental Geochemistry Laboratory Department of Environmental Sciences Faculty of Biological Sciences Quaid-i-Azam University Department of Environmental Sciences University of Baltistan Skardu Graduate School of Sciences and Engineering Kagoshima University Department of Earth and Planetary Environmental Science (UG) Graduate School of Science The University of Tokyo Department of Earth and Planetary Physics (UG) Graduate School of Science The University of Tokyo Department of Earth and Planetary Science (GR) Graduate School of Science The University of Tokyo

Arsenic(As) in natural hydrological systems is known as a worldwide major environmental concern. A geochemical and sedimentological study was done to ascertain the origin and geographical distribution of As in surface water and fluvial sediment collected from the floodplains/basins of the River Indus and its four major tributaries that drain through the northern Pakistan. The hydrogeochemical compositions of all five rivers were similar with calcium(Ca2+) and bicarbonate(HCO3-) being the dominating ions. The concentration of As ranged from 0.62-24.05 μg/L(average 3.7 ± 3.5 μg/L, n = 61) in river water, 2.3-23.4 mg/kg(average 5.7 ± 3.9 mg/kg) in suspended sediment, and 2.0-13 mg/kg(average4.13 ± 2.3 mg/kg) in fluvial sediment. Various approaches were used, including mineralogical, sequential extraction, geochemical, and statistical analyses to investigate the distribution, behavior, and potential sources of As in the sediment. The effect of geological factors on the distribution of As was also *** noticeable changes in the relative abundance of minerals were observed in the sediment at different locations along the river. Both mineralogical and statistical analyses showed that silicate minerals like muscovite, biotite, and chloride are the main As reservoir while oxides minerals like hematite and magnetite, which are minor components in the sediment are second largest As carrier. A geochemical baseline, using the normalization and cumulative frequency distribution curves was constructed for *** estimated mean human contribution of As was 3.4% in the Indus River, 1.9% in the Jhelum River, 13.7%in the Chenab River, 17.5% in the Ravi River and 5.4% in the Sutlej River, indicating relatively higher effects of anthropogenic activity along the Chenab River and Ravi River. The almost negligible effects of anthropogenic activities were additionally confirmed through the pollution assessment parameters estimated from the geo-enrichment, contamination factors, and ac

关键词： Arsenic Indus basin Geochemical baseline Source Contamination assessment