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Foliation and the First Law of Black Hole Thermodynamics

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Chinese Physics Letters 2011年第5期28卷 54-56页

作者： Azad A.Siddiqui Syed muhammad Jawwad Riaz M.akbar Department of Basic Sciences and Humanities EME CollegeNational University of Sciences and Technology(NUST)Peshawar RoadRawalpindiPakistan Centre for Advanced Mathematics and Physics National University of Sciences and Technology(NUST)Sector H-12IslamabadPakistan

There has been lots of interest in exploring the thermodynamic properties at the horizon of a black hole *** has been shown earlier that for different spacetimes,the Einstein field equations at the horizon can be expressed as the first law of black hole *** the idea of foliation,we develop a simpler procedure toobtain such *** considerγ=constant slices,for the Schwarzschild and Reissner-Nordstrom black hole *** Einstein field equations for the induced 3-dimensional metrics of the hypersurfaces are expressed in thermodynamic quantities under the virtual displacements of the *** expected,it is found that the field equations of the induced metric corresponding to the horizon can be written as afirst law of black hole *** is to be mentioned here that our procedure is much easier,to obtain such results,as here one has to essentially deal with(n-1)-dimensional induced metric for an n-dimensional spacetime.

关键词： thermodynamic Einstein mentioned

From Markers to Genome Based Breeding in Horticultural Crops: An Overview

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 183-204页

作者： Riaz Ahmad muhammad akbar Anjum Rashad Mukhtar Balal Department of Horticulture Bahauddin Zakariya UniversityMultan60800Pakistan Department of Horticulture University of SargodhaSargodha40100Pakistan

Molecular markers,genome sequencing and genome editing are considered as efficient tools to accomplish demands of plant breeders for crop improvement *** and biochemical markers have not been extensively used as these are greatly influenced by environmental *** molecular markers and sequencing techniques are routinely used in evaluation of genetic diversity and evolutionary relationship,accurate classification or taxonomy,characterization of germplasm,identification of hybrids and phylogenetic *** and undesired traits controlled by genes can be identified through different molecular markers technology all over the *** molecular markers are well established and have successfully been used for genetic analysis of different plants during last two ***,advanced techniques of molecular markers have been developed,which provide advance genotypic platform and tends to merge valuable properties of many basic *** class of markers also includes little modifications in basic methods to enhance the sensitivity and ***,plant breeders and strong investment are strongly linked for crop improvement *** review provides detailed description of different markers,genome sequencing and genome editing that have been utilized for different genetic analyses of horticultural *** editing technologies based on CRISPR/Cas are now successfully applied in horticultural ***,current review encourages the use of molecular marker technology for DNA fingerprinting,bar coding,sequencing,re-sequencing QTL mapping,genome association mapping and genome *** is need of time that diverse germplasm should be identified with different molecular techniques and further utilized in breeding purposes to achieve higher yielding and resistant cultivars against biotic and abiotic stresses.

关键词： Genetic analysis genome sequencing genome editing molecular markers plant breeders

Quantitative estimation of dust fall and smoke particles in Quetta Valley

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第7期7卷 542-547页

作者： SAMI muhammad WASEEM Amir akbar Sher Department of Chemistry University of Balochistan Quetta 87300 Pakistan

Tightening of air quality standards for populated urban areas has led to increasing attention to assessment of air quality management areas, where violation of air quality standards occurs, and development of control strategies to eliminate such vio-lation of air quality standards. The Quetta urban area is very densely built and has heavy motorized traffic. The increase of emis-sions mainly from traffic and industry are responsible for the increase in atmospheric pollution levels during the last years. The dust examined in the current study was collected by both deposit gauge and Petri dish methods at various sites of Quetta Valley. Smoke particles were obtained by bladder method from the exhausts of various types of motor vehicles. The concentration of lead found in the smoke ranged from 1.5×10?6 to 4.5×10?6.

关键词： Particulate matter (PM) Dust fall Smoke Lead Gasoline

Influence of Various Earth-Retaining Walls on the Dynamic Response Comparison Based on 3D Modeling

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2835-2863页

作者： muhammad akbar Huali Pan Jiangcheng Huang Bilal Ahmed Guoqiang Ou Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu610000China Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Department of Structural Engineering Faculty of Civil EngineeringDoctoral SchoolAkademicka 2Silesian University of TechnologyGliwice44-100Poland

The present work aims to assess earthquake-induced earth-retaining(ER)wall *** study is on the dynamics analysis of various earth-retaining wall designs in hollow precast concrete panels,reinforcement concrete facing panels,and gravity-type earth-retaining *** finite element(FE)simulations utilized a 3D plane strain condition to model full-scale ER walls and numerous nonlinear dynamics *** seismic performance of differentmodels,which includes reinforcement concrete panels and gravity-type and hollowprecast concrete ER walls,was simulated and examined using the FE *** also displays comparative studies such as stress distribution,deflection of the wall,acceleration across the wall height,lateral wall displacement,lateral wall pressure,and backfill plastic *** components of the created ER walls were found throughout this research *** is a granular reinforcement backfill,while the other is a wall-facing panel and base *** dynamic response effects of varied earth-retaining walls have also been *** was discovered that the facing panel of the model significantly impacts the earthquake-induced displacement of ER *** proposed analytical model’s validity has been evaluated and compared with the reinforcement concrete facing panels,gravity-type ER wall,scientifically available data,and American Association of State Highway and Transportation Officials(AASHTO)guidelines results based on FE *** results of the observations indicate that the hollow prefabricated concrete ER wall is the most feasible option due to its lower displacement and high-stress distribution compared to the two *** methodology and results of this study establish standards for future analogous investigations and professionals,particularly in light of the increasing computational capabilities of desktop computers.

关键词： Seismic analysis finite element modeling earth-retaining ER walls dynamic response structural resilience

2D MXene Ti_(3)C_(2)T_(x)Enhanced Plasmonic Absorption in Metasurface for Terahertz Shielding

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Computers, Materials & Continua 2023年第5期75卷 3453-3464页

作者： Zaka Ullah Muath Al Hasanl Ismail Ben Mabrouk muhammad junaid Fawad Sheikh Faculty of Electrical Engineering College of EngineeringAl Ain UniversityAl Ain64141UAE Department of Electrical Engineering Durham UniversityDurhamUK Department of Electrical Engineering Baluchistan University of Technology and management sciencesQuettaPakistan Institute of Digital Signal Processing Universitat Duisburg EssenDuisburgGermany

With the advancement of technology,shielding for terahertz(THz)electronic and communication equipment is increasingly *** metamaterial absorption technique is mostly used to shield electromagnetic interference(EMI)in THz sensing *** most widely used THz metamaterial absorbers suffer from their narrowband properties and the involvement of complex fabrication *** with multifunctional properties,such as adjustable conductivity,broad bandwidth,high flexibility,and robustness,are driving future development to meet THz shielding *** this article,a theoretical simulation approach based on finite difference time domain(FDTD)is utilized to study the absorption and shielding characteristics of a two-dimensional(2D)MXene Ti_(3)C_(2)T_(x) metasurface absorber in the THz *** proposed metamaterial structure is made up of a square-shaped array of MXene that is 50 nmthick and is placed on top of a silicon *** bottom surface of the silicon is metalized with gold to reduce the transmission and ultimately enhance the absorption at 1–3 *** symmetric adjacent space between theMXene array results in a widening of *** proposed metasurface achieves 96%absorption under normal illumination of the incident source and acquires an average of 25 dB shielding at 1 THz bandwidth,with the peak shielding reaching 65 *** results show that 2D MXene-based stacked metasurfaces can be proven in the realization of low-cost devices for THz shielding and sensing applications.

关键词： EMI shielding terahertz plasmonic absorber metasurface

A Framework of Deep Learning and Selection-Based Breast Cancer Detection from Histopathology Images

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Computer Systems Science & Engineering 2023年第5期45卷 1001-1016页

作者： muhammad junaid Umer muhammad Sharif Majed Alhaisoni Usman Tariq Ye Jin Kim Byoungchol Chang Department of Computer Science COMSATS University IslamabadWah CampusWah CanttPakistan Computer Sciences Department College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman University(PNU)P.O.BOX 84428Riyadh11671Saudi Arabia College of Computer Engineering and Science Prince Sattam Bin Abdulaziz UniversityAl-Kharaj11942Saudi Arabia Department of Computer Science Hanyang UniversitySeoul04763Korea Center for Computational Social Science Hanyang UniversitySeoul04763Korea

Breast cancer(BC)is a most spreading and deadly cancerous malady which is mostly diagnosed in middle-aged women worldwide and effecting beyond a half-million people every *** BC positive newly diagnosed cases in 2018 reached 2.1 million around the world with a death rate of 11.6%of total *** diagnosis and detection of breast cancer disease with proper treatment may reduce the number of *** gold standard for BC detection is biopsy analysis which needs an expert for correct *** diagnosis of BC is a complex and challenging *** work proposed a deep learning-based(DL)solution for the early detection of this deadly disease from histopathology *** evaluate the robustness of the proposed method a large publically available breast histopathology image database containing a total of 277524 histopathology images is *** proposed automatic diagnosis of BC detection and classification mainly involves three ***,a DL model is proposed for feature ***,the extracted feature vector(FV)is passed to the proposed novel feature selection(FS)framework for the best ***,for the classification of BC into invasive ductal carcinoma(IDC)and normal class different machine learning(ML)algorithms are *** outcomes of the proposed methodology achieved the highest accuracy of 92.7%which shows that the proposed technique can successfully be implemented for BC detection to aid the pathologists in the early and accurate diagnosis of BC.

关键词： Breast cancer deep learning FS IDC ML SVM

Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya

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Journal of Mountain Science 2024年第1期21卷 200-217页

作者： Hamza DAUD Javed Iqbal TANOLI Sardar muhammad ASIF muhammad QASIM muhammad ALI junaid KHAN Zahid Imran BHATTI Ishtiaq Ahmad Khan JADOON Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Department of Earth Sciences COMSATS University IslamabadAbbottabad Campus 22010Pakistan Department of Earth Sciences Sultan Qaboos UniversityAl-KhoudMascat 123Oman Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China Department of Earth Sciences Abbottabad University of Science and TechnologyHavelian 22500Pakistan

The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.

关键词： North Pakistan Debris flow Flow-R Propagation Susceptibility mapping Debris-flow inventory Weighted Overlay Method

Numerical evaluation of new Austrian tunneling method excavation sequences: A case study

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International Journal of Mining Science and Technology 2020年第3期30卷 381-386页

作者： Hafeezur Rehman Abdul Muntaqim Naji Wahid Ali muhammad junaid Rini Asnida Abdullah Han-kyu Yoo Department of Civil and Environmental Engineering Hanyang UniversityAnsan 15588South Korea Department of Mining Engineering Faculty of EngineeringBUITEMSQuetta 87300Pakistan Department of Geological Engineering Faculty of EngineeringBUITEMSQuetta 87300Pakistan Department of Geotechnics and Transportation Faculty of Civil EngineeringUniversiti Teknologi Malaysia81310 Johor BahruJohorMalaysia

The main aspects that require attention in tunnel design in terms of safety and economy are the precise estimation of probable ground conditions and ground behavior during construction. The variation in rock mass behavior due to tunnel excavation sequence plays an important role during the construction *** purpose of this research is to numerically evaluate the effect of excavation sequence on the ground behavior for the Lowari tunnel project, Pakistan. For the tunnel stability, the ground behavior observed during the actual partial face excavation sequence is compared with the top heading and bench excavation sequence. For this purpose, the intact rock parameters are used along with the characterization of rock mass joints related parameters to provide input for numerical modelling via FLAC 2D. The in-situ stresses for the numerical modelling are obtained using empirical equations. From the comparison of the two excavation sequences, it was observed that the actual excavation sequence used for Lowari tunnel construction utilized more support than the top heading and bench method. However, the actual excavation sequence provided good results in terms of stability.

关键词： Conventional excavation Excavation sequence Numerical modelling High in-situ stresses Jointed rock mass

Advanced Study of Unsteady Heat and Chemical Reaction with Ramped Wall and Slip Effect on a Viscous Fluid

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Communications in Theoretical Physics 2017年第3期67卷 301-308页

作者： Ayesha Sohail K.Maqbool Noreen Sher akbar muhammad Younas Department of Mathematics COMSATS Institute of Information technology Lahore Pakistan Department of Mathematics & Statistics FBAS IIU Islamabad 44000 Pakistan DBS&H CEME National University of Sciences and DBS&H CEME National University of Sciences and Technology Islamabad Pakistan

This paper investigate the effect of slip boundary condition, thermal radiation, heat source, Dufour number,chemical reaction and viscous dissipation on heat and mass transfer of unsteady free convective MHD flow of a viscous fluid past through a vertical plate embedded in a porous media. Numerical results are obtained for solving the nonlinear governing momentum, energy and concentration equations with slip boundary condition, ramped wall temperature and ramped wall concentration on the surface of the vertical plate. The influence of emerging parameters on velocity,temperature and concentration fields are shown graphically.

关键词： free convection thermal radiation MHD viscous dissipation chemical reaction heat source Dufour number porous media