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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1180-1187页

作者： mohsin usman qureshi Zafar Mahmood Ali Murtaza Rasool Faculty of Engineering Sohar UniversitySoharOman University of Buraimi Al BuraimiOman National Engineering Services Pakistan Lahore54700Pakistan

The assessment of in situ permeability of rock mass is challenging for large-scale projects such as reservoirs created by dams,where water tightness issues are of prime *** in situ permeability is strongly related to the frequency and distribution of discontinuities in the rock mass and quantified by rock quality designation(RQD).This paper analyzes the data of hydraulic conductivity and discontinuities sampled at different depths during the borehole investigations in the limestone and sandstone formations for the construction of hydraulic structures in *** recovered from boreholes provide RQD data,and in situ Lugeon tests elucidate the permeability.A modern technique of multivariate adaptive regression splines(MARS)assisted in correlating permeability and RQD along with the *** situ permeability shows a declining trend with increasing RQD,and the depth of investigation is within 50 *** type of relationship can be developed based on detailed initial investigations at the site where the hydraulic conductivity of discontinuous rocks is required to be *** relationship can approximate the permeability by only measuring the RQD in later investigations on the same site,thus saving the time and cost of the site *** applicability of the relationship developed in this study to another location requires a lithological similarity of the rock mass that can be verified through preliminary investigation at the site.

关键词： In situ permeability Limestone Sandstone Lugeon Rock quality designation(RQD) Multivariate adaptive regression splines (MARS)

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De-convolution and De-noising of SAR Based GPS Images Using Hybrid Particle Swarm Optimization

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Chinese Journal of Electronics 2023年第1期32卷 166-176页

作者： Rizwan Sadiq Muhammad Bilal qureshi Muhammad mohsin Khan Dept.of Electrical and Electronic Engineering Koc University Dept.of Electrical and Computer Engineering COMSATS University Dept.of Radiology and Biomedical Imaging Yale University Sino-Pak Center for Artificial Intelligence (SPCAI) Pak-Austria Fachhochschule:Institute of Applied Sciences and Technology (PAF-IAST)

Synthetic aperture radar(SAR) imaging is an efficient strategy which exploits the properties of microwaves to capture images. A major concern in SAR imaging is the reconstruction of image from back scattered signals in the presence of noise. The reflected signal consist of more noise than the target signal and it is a challenging problem to reduce the noise in the collected signal for better reconstruction of an image. Current studies mostly focus on filtering techniques for noise removal. This can result in an undesirable point spread function causing extreme smearing effect in the desired image. In order to handle this problem, a computational technique, particle swarm optimization(PSO) is used for de-noising purpose and later the target performance is further improved by an amalgamation of Wiener ***, to improve the de-noising performance we have exploited the singular value decomposition based morphological filtering. To justify the proposed improvements we have simulated the proposed techniques and results are compared with the conventional existing models. The proposed method revealed considerable decrease in mean square error compared to Wiener filter and PSO techniques. Quantitative analysis of image restoration quality are also presented in comparison with Wiener filter and PSO based on the improvement in signal to noise ratio and peak signal to noise ratio.

关键词： Radar remote sensing Wiener filters Filtering Statistical analysis Radar polarimetry Particle swarm optimization Synthetic aperture radar

Optimization of moderator assembly for neutron flux measurement:experimental and theoretical approaches

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Nuclear Science and Techniques 2017年第5期28卷 7-12页

作者： Abdul Waheed Nawab Ali Muzahir A.Baloch Aziz A.qureshi Eid A.Munem Muhammad usman Rajput Tauseef Jamal Wazir Muhammad Radiation Physics Laboratory Physics DepartmentCOMSATS Institute of Information Technology(CIIT)

A moderator of paraffin wax assembly has been demonstrated where its thickness can be optimized to thermalize fast neutrons. The assembly is used for measuring fast neutron flux of a neutron probe at different neutron energies, using BF03(U10and 200) and3He(U0.500)neutron detectors. The paraffin wax thickness was optimized at 6 cm for the neutron probe which contains an Am–Be neutron source. The experimental data are compared with Monte Carlo simulation results using MCNP5 version 1.4. Neutron flux comparison and neutron activation techniques are used for measuring neutron flux of the neutron probe to validate the optimum paraffin moderator thickness in the assembly. The neutron fluxes are measured at(1.17 ± 0.09) 9 105 and(1.19 ± 0.1) 9 105n/s, being in agreement with the simulated values. The moderator assembly can easily be utilized for essential requirements of neutron flux measurements.

关键词： Am–Be and 252Cf neutron sources BF3&3He detectors Paraffin wax Neutron flux Monte Carlo simulation

Risk of infection with arboviruses in a healthy population in Pakistan based on seroprevalence

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Virologica Sinica 2024年第3期39卷 369-377页

作者： Shengyao Chen Muhammad Saqib Hafiz Sajid Khan Yuan Bai usman Ali Ashfaq Muhammad Khalid Mansoor Abulimti Moming Jing Liu Min Zhou Saifullah Khan Niazi Qiaoli Wu Awais-Ur-Rahman Sial Shuang Tang Muhammad Hassan Sarfraz Aneela Javed Sumreen Hayat mohsin Khurshid Iahtasham Khan Muhammad Ammar Athar Zeeshan Taj Bo Zhang Fei Deng Ali Zohaib Shu Shen Key Laboratory of Virology and National Virus Resource Center Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Faculty of Veterinary Science University of Agriculture FaisalabadFaisalabad 38040Pakistan The Children's Hospital Faisalabad 38000Pakistan Department of Bioinformatics and Biotechnology Government College University FaisalabadFaisalabad 38000Pakistan f Department of Microbiology Faculty of Veterinary and Animal SciencesThe Islamia University of BahawalpurBahawalpur 63100Pakistan Hubei Jiangxia Laboratory Wuhan 430200China Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China Armed Forces Institute of Pathology(AFIP) Rawalpindi 46000Pakistan Department of Clinical Studies Faculty of Veterinary&Animal SciencesPir Mehr Ali Shah Arid Agriculture UniversityRawalpindi 46300Pakistan Institute of Microbiology Government College University FaisalabadFaisalabad 38000Pakistan l Atta-ur-Rahman School of Applied Biosciences National University of Science and TechnologyIslamabad 44000Pakistan Department of Clinical Sciences University of Veterinary and Animal SciencesLahore Sub-campusJhang 35200Pakistan Department of Molecular Pathology National Medical Center DHA Phase 1Karachi 75500Pakistan

Infectious diseases caused by arboviruses are a public health concern in ***,studies on data prevalence and threats posed by arboviruses are *** study investigated the seroprevalence of arboviruses in a healthy population in Pakistan,including severe fever with thrombocytopenia syndrome virus(SFTSV),Crimean-Congo hemorrhagic fever virus(CCHFV),Tamdy virus(TAMV),and Karshi virus(KSIV)based on a newly established luciferase immunoprecipitation system(LIPS)assays,and Zika virus(ZIKV)by enzyme-linked immunosorbent assays(ELISA).Neutralizing activities against these arboviruses were further examined from the antibody positive *** results showed that the seroprevalence of SFTSV,CCHFV,TAMV,KSIV,and ZIKV was 17.37%,7.58%,4.41%,1.10%,and 6.48%,respectively,and neutralizing to SFTSV(1.79%),CCHFV(2.62%),and ZIKV(0.69%)were identified,as well as to the SFTSV-related Guertu virus(GTV,0.83%).Risk factors associated with the incidence of exposure and levels of antibody response were ***,co-exposure to different arboviruses was demonstrated,as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing ***,individuals aged40 years,and outdoor workers had a high risk of exposure to *** these results reveal the substantial risks of infection with arboviruses in Pakistan,and indicate the threat from co-exposure to multiple *** findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.

关键词： Arbovirus Pakistan Seroprevalence Tick-borne virus Mosquito-borne virus

Countrywide Survey for MERS-Coronavirus Antibodies in Dromedaries and Humans in Pakistan

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Virologica Sinica 2018年第5期33卷 410-417页

作者： Ali Zohaib Muhammad Saqib Muhammad Ammar Athar Jing Chen Awais-ur-Rahman Sial Saeed Khan Zeeshan Taj Halima Sadia usman Tahir Muhammad Haleem Tayyab Muhammad Asif qureshi Muhammad Khalid Mansoor Muhammad Ahsan Naeem Bing-Jie Hu Bilal Ahmed Khan Ikram Din Ujjan Bei Li Wei Zhang Yun Luo Yan Zhu Cecilia Waruhiu Iahtasham Khan Xing-Lou Yang Muhammad Sohail Sajid Victor Max Corman Bing Yan Zheng-Li Shi CAS Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Ctunese Academy of Sciences Beijing 100049China Faculty of Veterinary Medicine University of AgricultureFaisalabad 38040Pakistan Laboratory of Cancer Biomarkers and Liquid Biopsy College of PharmacyHenan UniversityHenan 475004China Department of Clinical Studies Faculty of Veterinary and Animal SciencesPMAS-Arid Agriculture UniversityRawalpindi 46000Pakistan Dow University of Health Science Pakistan Karachi 74200 Department of Microbiology Government College University FaisalabadFaisalabad 38000Pakistan Livestock and Dairy Development Department(L&DD) Lahore 54000Pakistan College of Veterinary and Animal Sciences The Islamia University of BahawalpurBahawalpur 63100Pakistan State Key Laboratory of Agricultural Mlcroblology Huazhong Agricultural UniversityWuhan 430070China Liaqat University of Medical and Health Science Pakistan Jamshoro 76090 Section of Epidemiology and Public Health Department of Chnical SciencesUniversity of Veterinary and Animal SciencesLahore subcampusJhang 35200Pakistan Institute of Virology Chadte-Universitatsmedizin BerlinCorporate member of Free UniversityHumboldt-University and Berlin Institute of HealthBerlin 10117Germany German Center for Infection Research(DZIF) Berlin 10117Germany

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen capable of causing severe respiratory disease in humans. Although dromedary camels are considered as a major reservoir host, the MERS-CoV infection dynamics in camels are not fully understood. Through surveillance in Pakistan, nasal (n = 776) and serum (n = 1050)samples were collected from camels between November 2015 and February 2018. Samples were collected from animal markets, free-roaming herds and abattoirs. An in-house ELISA was developed to detect IgG against MERS-CoV. A total of 794 camels were found seropositive for MERS-CoV. Prevalence increased with the age and the highest seroprevalence was recorded in camels aged [ 10 years (81.37%) followed by those aged 3.1–10 years (78.65%) and B 3 years (58.19%).Higher prevalence was observed in female (78.13%) as compared to male (70.70%). Of the camel nasal swabs, 22 were found to be positive by RT-qPCR though with high Ct values. Moreover, 2,409 human serum samples were also collected from four provinces of Pakistan during 2016–2017. Among the sampled population, 840 humans were camel *** we found a high rate of MERS-CoV antibody positive dromedaries (75.62%) in Pakistan, no neutralizing antibodies were detected in humans with and without contact to camels.

关键词： Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Camel -Human Pakistan

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