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| 1 | Nonlinear joint PP-PS AVO inversion based on improved Bayesian inference and LSSVM显示文摘Multiwave seismic technology promotes the application of joint PP–PS amplitude versus offset (AVO) inversion;however conventional joint PP–PS AVO inversioan is linear based on approximations of the Zoeppritz equations for multiple iterations. Therefore the inversion results of P-wave, S-wave velocity and density exhibit low precision in the faroffset;thus, the joint PP–PS AVO inversion is nonlinear. Herein, we propose a nonlinear joint inversion method based on exact Zoeppritz equations that combines improved Bayesian inference and a least squares support vector machine (LSSVM) to solve the nonlinear inversion problem. The initial parameters of Bayesian inference are optimized via particle swarm optimization (PSO). In improved Bayesian inference, the optimal parameter of the LSSVM is obtained by maximizing the posterior probability of the hyperparameters, thus improving the learning and generalization abilities of LSSVM. Then, an optimal nonlinear LSSVM model that defi nes the relationship between seismic refl ection amplitude and elastic parameters is established to improve the precision of the joint PP–PS AVO inversion. Further, the nonlinear problem of joint inversion can be solved through a single training of the nonlinear inversion model. The results of the synthetic data suggest that the precision of the estimated parameters is higher than that obtained via Bayesian linear inversion with PP-wave data and via approximations of the Zoeppritz equations. In addition, results using synthetic data with added noise show that the proposed method has superior anti-noising properties. Real-world application shows the feasibility and superiority of the proposed method, as compared with Bayesian linear inversion. | Xie Wei Wang Yan-Chun Liu Xue-Qing Bi Chen-Chen Zhang Feng-Qi Fang Yuan Tahir Azeem | 2019 | Applied Geophysics2019，16，1： | 7 |
| 2 | The electronic and magnetic properties of wurtzite Mn:CdS, Cr:CdS and Mn:Cr:CdS: first principles calculations显示文摘In this article, density functional theory(DFT) based on generalized gradient approximation(GGA)and GGACU, U is Hubbard term, is used to study the electronic properties of CdS doped with different dopants(Cr, Mn). The calculations are carried out for Mn-doped CdS, Cr-doped CdS, and co-doping of Mn/Cr in CdS simultaneously. It is found that hopping of electrons is possible with Cr:CdS and Mn:Cr:CdS while Mn:CdS does not allow the hopping of electrons. Moreover, double exchange interactions are observed in Cr:CdS and d-d superexchange interactions are observed in Mn:CdS. Now the problem becomes interesting when one magnetic ion(Cr) supporting double exchange interactions and another ion(Mn) supporting d-d super-exchange interactions are doped simultaneously in the same system(CdS). The co-doped CdS is more stable even at high Curie temperature due to p-d double exchange interactions and d-d super exchange interactions. Furthermore, the Cr-3d and Mn-3d states present in-between the band gap are responsible for inner shell transitions and hence for optical properties.Therefore, the co-doped system is taken into account to enhance its applications in the field of spintronic and magneto-optical devices. | Azeem Nabi Zarmeena Akhtar Tahir Iqbal Atif Ali Muhammad Arshad Javid | 2017 | Journal of Semiconductors2017，38，7： | 2 |
| 3 | 2D Carbon Fiber Reinforced High Density Polyethylene Multi-Layered Laminated Composite Panels:Structural,Mechanical,Thermal,and Morphological Profile显示文摘Carbon fiber reinforced high density polyethylene multi-layered laminated composite panels(HDPE/CF MLCP) with excellent in-plane properties along transverse direction have been formulated. Composite architectures with carbon fiber(CF) designed in 2D layout in conventional composites can alleviate their properties in thickness direction, but all attempts so far developed have achieved restrained success. Here,we have exposed an approach to the high strength composite challenge, without altering the 2D stack design on the basis of concept of fiber reinforced laminated composites that would provide enhanced mechanical and thermal properties along transverse direction. CF sheets allowed the buckling of adjoining plies in 2D MLCP. We fabricated 2D MLCP by stacking the alternative CF and HDPE layers under different loading conditions, which resulted in high strength composites. These plies of CF and HDPE served as unit cells for MLCP, with CF offering much-needed fracture toughness and hardness to these materials.For 2D HDPE/CF MLCP, we demonstrated noteworthy improvement in physical and chemical interaction between CF and HDPE, in-plane fracture strain, flexural strength(30.684 MPa), bending modulus(7436.254 MPa), thermal stability(40.94%), and surface morphology, upon increasing the CF layers up to twenty, enabling these composites truly for high temperature and high strength applications. | Shahzad Maqsood Khan Nafisa Gull Muhammad Azeem Munawar Atif Islam Saba Zia Muhammad Shafiq Aneela Sabir Syed Muhammad Awais Muhammad Arif Butt Muhammad Taqi Zahid Butt Tahir Jamil | 2016 | Journal of Materials Science & Technology2016，32，10： | 1 |
| 4 | Analysis of Heat Transport in a Powell-Eyring Fluid with Radiation and Joule Heating Effects via a Similarity Transformation显示文摘Heat transfer in an Eyring-Powell fluid that conducts electricity and flows past an exponentially growing sheet is considered.As the sheet is stretched in the x direction,the flow develops in the region with y>0.The problem is tackled through a set of partial differential equations accounting for Magnetohydrodynamics(MHD),radiation and Joule heating effects,which are converted into a set of equivalent ordinary differential equations through a similarity transformation.The converted problem is solved in MATLAB in the framework a fourth order accurate integration scheme.It is found that the thermal relaxation period is inversely proportional to the thickness of the thermal boundary layer,whereas the Eckert-number displays the opposite trend.As this characteristic number grows,the temperature within the channel increases. | Tahir Naseem Iqra Bibi Azeem Shahzad Mohammad Munir | 2023 | Fluid Dynamics & Materials Processing2023，19，3： | 1 |
| 5 | Identification and Visualization of Spatial and Temporal Trends in Textile Industry显示文摘The research volume increases at the study rate,causing massive text corpora.Due to these enormous text corpora,we are drowning in data and starving for information.Therefore,recent research employed different text mining approaches to extract information from this text corpus.These proposed approaches extract meaningful and precise phrases that effectively describe the text’s information.These extracted phrases are commonly termed keyphrases.Further,these key phrases are employed to determine the different fields of study trends.Moreover,these key phrases can also be used to determine the spatiotemporal trends in the various research fields.In this research,the progress of a research field can be better revealed through spatiotemporal bibliographic trend analysis.Therefore,an effective spatiotemporal trend extraction mechanism is required to disclose textile research trends of particular regions during a specific period.This study collected a diversified dataset of textile research from 2011–2019 and different countries to determine the research trend.This data was collected from various open access journals.Further,this research determined the spatiotemporal trends using quality phrasemining.This research also focused on finding the research collaboration of different countries in a particular research subject.The research collaborations of other countries’researchers show the impact on import and export of those countries.The visualization approach is also incorporated to understand the results better. | Umair Yousaf Muhammad Asif Shahbaz Ahmed Noman Tahir Azeem Irshad Akber Abid Gardezi Muhammad Shafiq Jin-Ghoo Choi Habib Hamam | 2023 | Computers, Materials & Continua2023，，2： | 0 |
| 6 | Genome-wide association analysis for stripe rust resistance in spring wheat(Triticum aestivum L.) germplasm显示文摘Stripe rust is a continuous threat to wheat crop all over the world.It causes considerable yield losses in wheat crop every year.Continuous deployment of adult plant resistance(APR)genes in newly developing wheat cultivars is the most judicious strategy to combat this disease.Herein,we dissected the genetics underpinning stripe rust resistance in Pakistani wheat germplasm.An association panel of 94 spring wheat genotypes was phenotyped for two years to score the infestation of stripe rust on each accession and was scanned with 203 polymorphic SSRs.Based on D’measure,linkage disequilibrium(LD)exhibited between loci distant up to 45 c M.Marker-trait associations(MTAs)were determined using mixed linear model(MLM).Total 31 quantitative trait loci(QTLs)were observed on all 21 wheat chromosomes.Twelve QTLs were newly discovered as well as 19 QTLs and 35 previously reported Yr genes were validated in Pakistani wheat germplasm.The major QTLs were QYr.uaf.2 AL and QYr.uaf.3 BS(PVE,11.9%).Dissection of genes from the newly observed QTLs can provide new APR genes to improve genetic resources for APR resistance in wheat crop. | Sher MUHAMMAD Muhammad SAJJAD Sultan Habibullah KHAN Muhammad SHAHID Muhammad ZUBAIR Faisal Saeed AWAN Azeem iqbal KHAN Muhammad Salman MUBARAK Ayesha TAHIR Muhammad UMER Rumana KEYANI Muhammad InamAFZAL Irfan MANZOOR Javed Iqbal WATTOO Aziz-ur REHMAN | 2020 | Journal of Integrative Agriculture2020，19，8： | 0 |
| 7 | Exploring Placer Gold Deposits through Integrated Geophysical and Geochemical Techniques at the Confluence of the Indus and Kabul Rivers,NW Pakistan显示文摘Analysis of the anomalous magnetic mineral intensities and geochemistry for placer gold deposits are presented for those of the Attock area at the confluence of the Indus and Kabul rivers in northwestern Pakistan.Two grids covering an area of 10 x18 m2 and 8 x10 m2 were analyzed using a G-858 Cesium Vapor Magnetometer.The anomalous zones obtained were plotted on contour maps,2 D and 3 D magnetic intensity maps.Based on the magnetic anomalies,grid-1 of the study area was sampled at three different anomalous zones for geochemical analysis.These zones contain gold concentrations,ranging from 2.11 ppm to 6.109 ppm with an average of 4.01 ppm.Increase in gold concentration in the subsurface within the anomalous zones indicates that magnetometer survey followed by a geochemical analysis can potentially narrow down the gold-bearing anomalous zones. | Asghar ALI Khaista REHMAN Owais TAYYAB Tahir ZAMAN Mahad JAMEEL Azeem KHAN Rafique AHMAD Muhammad IRFAN | 2020 | Acta Geologica Sinica(English Edition)2020，94，5： | 0 |
| 8 | Study of pure and semileptonic decays of D_s meson within R-parity violating supersymmetric model显示文摘We present the comaprative study of semileptonic and leptonic decays of Ds, D±and D0meson(D →M l+-αl-β, D → l+αlβ, D → l+αvα;α,β=e,μ) within the framework of R-parity violating the( Rp) Minimal Supersymmetric Standard Model(MSSM). The comparison shows that combination and product couplings,(λβiαλ* ij qor λβqkλ*αj k)contribution to the branching fractions of the said processes(under consideration) is consistent with or comparable to the experimental measurements in most of the cases. However, some cases exist where these contributions are highly suppressed. We identify such cases in our analysis and single out the important ones suitable for exploring in the future and current experiments. | Farida Tahir Azeem Mir Shakeel Mahmood | 2014 | Chinese Physics C2014，38，12： | 0 |
| 9 | Facies Analysis, Sequence Stratigraphy and Diagenetic Studies of the Jurassic Carbonates of the Kohat Basin, Northwest Pakistan: Reservoir Implications显示文摘The present study deals with the depositional facies, diagenetic processes and sequence stratigraphy of the shallow marine carbonates of the Samana Suk Formation, Kohat Basin, in order to elucidate its reservoir quality. The Samana Suk Formation consists of thin to thick-bedded, oolitic, bioclastic, dolomitic and fractured limestone. Based on the integration of outcrop, petrographic and biofacies analyses, the unit is thought to have been deposited on a gentle homoclinal ramp in peritidal, lagoonal and carbonate shoal settings. Frequent variations in microfacies based sea-level curve have revealed seven Transgressive Systems Tracts(TSTs) and six Regressive Systems Tracts(RSTs). The unit has undergone various stages of diagenetic processes, including mechanical and chemical compaction, cementation,micritization, dissolution and dolomitization. The petrographic analyses show the evolution of porosity in various depositional and diagenetic phases. The fenestral porosity was mainly developed in peritidal carbonates during deposition,while the burial dissolution and diagenetic dolomitization have greatly enhanced the reservoir potential of the rock unit, as is further confirmed by the plug porosity and permeability analyses. The porosities and permeabilities were higher in shoal facies deposited in TSTs, as compared to lagoonal and peritidal facies, except for the dolomite in mudstone, deposited during RSTs. Hence good, moderate and poor reservoir potential is suggested for shoal, lagoonal and peritidal facies,respectively. | Emadullah KHAN Abbas Ali NASEEM Suleman KHAN Bilal WADOOD Faisal REHMAN Maryam SALEEM Mubashir MEHMOOD Waqar AHMAD Zubair AHMED Tahir AZEEM | 2022 | Acta Geologica Sinica(English Edition)2022，96，5： | 0 |
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