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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

Second Powers of Cover Ideals of Paths

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Algebra Colloquium 2022年第4期29卷 669-686页

作者： Nursel Erey Ayesha Asloob qureshi Departmentof Mathematics Gebze Technical University GebzeKocaeli 41400Turkey Faculty of Engineering and Natural Sciences Sabanci University Orta MahalleTuzla 34956IstanbulTurkey

We show that the second power of the cover ideal of a path graph has linear *** prove our result we construct a recursively defined order on the generators of the ideal which yields linear *** construction has a natural generalization to the larger class of chordal *** generalization allows us to raise some questions that are related to some open problems about powers of cover ideals of chordal graphs.

关键词： cover ideal power of ideals linear quotient path vertex cover

Effect of Firing Temperature on the Electromagnetic Properties of Electronic Transformer Cores Developed by Using Nanosized Mn–Zn Ferrite Powders

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 159-163页

作者： Hassan Waqas Ammad Hussain qureshi muhammad Shahzad Materials Division Directorate of Technology PINSTECH

Current investigation deals with the effect of grain growth process as a function of sintering temperature on the electromagnetic properties （initial permeability, impedance, and gain） of Mn-Zn ferrite （MZF） cores （toroids）. By employing auto combustion process, nanosized [（20 ± 5） nm] MZF powders were synthesized and toroid shape cores were obtained after subsequent calcination and firing （sintering） process. It was observed that the submicron structure （0.5 μm） achieved in the ferrite core sintered at 1,000 ℃ was gradually transformed into micron size grains by increasing the firing temperature i.e., 1,100, 1,200, and 1,350 ℃. The results reveal that MZF core sintered at low temperature （1,000 ℃） showed high impedance, low initial permeability, and narrow working frequency range i.e., 3-15 MHz. However, the improvement in initial permeability, sintered density, and operational frequency range （100 kHz-17 MHz） was observed at high temperature （1,350 ℃） firing in the inert environment. This synthesized MZF core is more suitable for miniaturized switch mode power supply applications.

关键词： Mn-Zn ferrites Nanosized powders Impedance Sintering

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Detection of Lung Nodules on X-ray Using Transfer Learning and Manual Features

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Computers, Materials & Continua 2022年第7期72卷 1445-1463页

作者： Imran Arshad Choudhry Adnan N.qureshi Faculty of Information Technology University of Central PunjabLahorePakistan

The well-established mortality rates due to lung cancers,scarcity of radiology experts and inter-observer variability underpin the dire need for robust and accurate computer aided diagnostics to provide a second *** this end,we propose a feature grafting approach to classify lung cancer images from publicly available National Institute of Health(NIH)chest X-Ray dataset comprised of 30,805 unique *** performance of transfer learning with pre-trained VGG and Inception models is evaluated in comparison against manually extracted radiomics features added to convolutional neural network using custom *** classification with both approaches,Support VectorsMachines(SVM)are *** results from the 5-fold cross validation report Area Under Curve(AUC)of 0.92 and accuracy of 96.87%in detecting lung nodules with the proposed *** is a plausible improvement against the observed accuracy of transfer learning using Inception(79.87%).The specificity of allmethods is>99%,however,the sensitivity of the proposed method(97.24%)surpasses that of transfer learning approaches(<67%).Furthermore,it is observed that the true positive rate with SVM is highest at the same false-positive rate in experiments amongst Random Forests,Decision Trees,and K-Nearest Neighbor ***,the proposed approach can be used in clinical and research environments to provide second opinions very close to the experts’intuition.

关键词： Lungs cancer convolutional neural network hand-crafted feature extraction deep learning classification

Smart Security Framework for Educational Institutions Using Internet of Things(IoT)

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Computers, Materials & Continua 2019年第7期61卷 81-101页

作者： Afzal Badshah Anwar Ghani muhammad Ahsan qureshi Shahaboddin Shamshirband Department of Computer Science and Software Engineering International Islamic UniversityIslamabad44000Pakistan Faculty of Computing and Information Technology University of JeddahKhulais21959Kingdom of Saudi Arabia Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Information Technology Ton Duc Thang UniversityHo Chi Minh CityVietnam

Educational institutions are soft targets for the terrorist with massive and defenseless *** the recent past,numbers of such attacks have been executed around the *** research,in order to provide a secure environment to the educational institutions is a challenging *** effort is motivated by recent assaults,made at Army Public School Peshawar,following another attack at Charsada University,Khyber Pukhtun Khwa,Pakistan and also the Santa Fe High School Texas,USA *** study uses the basic technologies of edge computing,cloud computing and IoT to design a smart emergency alarm system *** is engaged in developing this world smarter,can contribute significantly to design the Smart Security Framework(SSF)for educational *** the emergency situation,all the command and control centres must be informed within seconds to halt or minimize the *** this article,the SSF is *** framework works on three *** first layer is the sensors and smart devices *** these sensors and smart devices are connected to the Emergency Control Room(ECR),which is the second layer of the proposed *** second layer uses edge computing technologies to process massive data and information *** third layer uses cloud computing techniques to transmit and process data and information to different command and control *** proposed system was tested on Cisco Packet Tracer *** result shows that this approach can play an efficient role in security alert,not only in the educational institutions but also in other organizations too.

关键词： Internet of things smart security framework massacres terrorism smart emergency alert

Hybridization of CNN with LBP for Classification of Melanoma Images

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Computers, Materials & Continua 2022年第6期71卷 4915-4939页

作者： Saeed Iqbal Adnan N.qureshi Ghulam Mustafa Faculty of Information Technology University of Central PunjabLahorePakistan Department of Computer Sciences Bahria University Lahore CampusPakistan

Skin cancer(melanoma)is one of the most aggressive of the cancers and the prevalence has significantly increased due to increased exposure to ultraviolet ***,timely detection and management of the lesion is a critical consideration in order to improve lifestyle and reduce *** this end,we have designed,implemented and analyzed a hybrid approach entailing convolutional neural networks(CNN)and local binary patterns(LBP).The experiments have been performed on publicly accessible datasets ISIC 2017,2018 and 2019(HAM10000)with data augmentation for in-distribution *** a novel contribution,the CNN architecture is enhanced with an intelligible layer,LBP,that extracts the pertinent visual *** of Basal Cell Carcinoma,Actinic Keratosis,Melanoma and Squamous Cell Carcinoma has been evaluated on 8035 and 3494 cases for training and testing,*** outcomes with cross-validation depict a plausible performance with an average accuracy of 97.29%,sensitivity of 95.63%and specificity of 97.90%.Hence,the proposed approach can be used in research and clinical settings to provide second opinions,closely approximating experts’intuition.

关键词： Skin cancer convolutional neural network feature extraction local binary pattern classification

Interactions of ferro-nanoparticles(hematite and magnetite) with reservoir sandstone: implications for surface adsorption and interfacial tension reduction

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Petroleum Science 2020年第4期17卷 1037-1055页

作者： Abdullah Musa ali Noorhana Yahya Saima qureshi Universiti Teknologi PETRONAS 32610 Seri IskandarPerakMalaysia Geology Department Bayero UniversityKanoKanoNigeria

There are a few studies on the use of ferro-nanofluids for enhanced oil recovery,despite their magnetic properties;hence,it is needed to study the adsorption of iron oxide(Fe2 O3 and Fe3 O4) nanoparticles(NPs) on rock *** is important as the colloidal transport of NPs through the reservoir is subject to particle adsorption on the rock *** dynamics simulation was used to determine the interfacial energy(strength) and adsorption of Fe2 O3 and Fe3 O4 nanofluids infused in reservoir *** transform infrared spectroscopy and X-ray photon spectroscopy(XPS) were used to monitor interaction of silicate species with Fe2 O3 and Fe3 *** spectral changes show the variation of dominating silicate anions in the ***,the XPS peaks for Si,C and Fe at 190,285 and 700 eV,respectively,are less distinct in the spectra of sandstone aged in the Fe3 O4 nanofluid,suggesting the intense adsorption of the Fe3 O4 with the crude *** measured IFT for brine/oil,Fe2 O3/oil and Fe3 O4/oil are 40,36.17 and 31 mN/m,***3 O4 infused with reservoir sandstone exhibits a higher silicate sorption capacity than Fe2 O3,due to their larger number of active surface sites and saturation magnetization,which accounts for the effectiveness of Fe3 O4 in reducing IFT.

关键词： Magnetite and hematite nanoparticles Rock surface adsorption Molecular dynamics simulation Interfacial tension(IFT)

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4-((4-Chlorophenylsulfonamido)methyl)cyclohexanecarboxylic Acid： Synthesis, Crystal Structure and Biological Activities

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Chinese Journal of Structural Chemistry 2017年第8期36卷 1307-1314页

作者： muhammad Danish RABIA Ayub Butt muhammad Nawaz Tahir muhammad Ashfaq SYEDA Tahira Hafeez muhammad Naeem Ahmed HALEEMA qureshi Department of Chemistry University of Gujrat Gujrat 50700 Pakistan Department of Physics University of Sargodha Sargodha Pakistan Department of Chemistry University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

In this study, a novel 4-（（4-chlorophenylsulfonamido）methyl）cyclohexanecarboxylic acid（C（14）H（18）ClNO4S） was synthesized by the reaction of tranexamic acid and 4-chlororbenzene sulfonyl chloride in basic medium at room temperature. The molecular structure was determined by FT-IR, NMR, elemental analysis and single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P21/c with a = 12.3120（11）, b = 16.5987（19）, c = 7.6873（7）？, β = 90.495（6）o, Z = 4 and V = 1570.9（3）？~3, crystal size（mm） = 0.38 × 0.16 × 0.14 and Rint = 0.045. In this compound, the carboxylic acid A（O（1）/C（1）/C（2）） and the sulfonyl B（O（3）/S（1）/O（4）） moieties are of course planar. The molecules are dimerized due to the O–H…O type of H-bonding with the R22（8） ring motifs. The dimmers are interlinked through C–H…O and N–H…O types of H-bonding. The synthesized compound was screened against four bacterial and two fungal strains and inactive against all strains. Antioxidant activity was checked against DPPH. Enzyme inhibition activity was carried out using three different enzymes and the title compound was more potent α-chymotrypsin inhibitor.

关键词： sulfonamide tranexamic acid 4-chlorobenzenesulfonyl chloride XRD biological applications

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Ethnobotanical inventory and folk uses of indigenous plants from Pir Nasoora National Park,Azad Jammu and Kashmir

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Asian Pacific Journal of Tropical Biomedicine 2015年第3期5卷 234-241页

作者： muhammad Shoaib Amjad muhammad Arshad Rahmatullah qureshi Department of Botany PMAS-University of Arid Agriculture Department of Botany Women University of Azad Jammu and Kashmir

Objective:To document the medicinal and other folk uses of native plants of the area with a view to preserve the ethnobotanical knowledge associated with this ***:The fieldwork was conducted during a period of one *** were collected through a semi-structured questionnaire and interviews with indigenous tribal people and traditional health practitioners residing in the study ***:The present study documented ethnobotanical uses of 104 plant species belonged to93 genera and 51 *** revealed that most of the documented species were used medicinally(78 spp..44.07%).Leaves were found to be the most frequently used part(69 spp..42.86%) for the preparation of indigenous recipes and for ***:The current research contributes significantly to the ethnobotanical *** depicts a strong human-plant *** is an urgent need to further document indigenous uses of plants for future domestication.

关键词： Ethnobotany Pir Nasoora Indigenous knowledge Conservation