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Effect of silica fum. on the fresh and hardened properties of fly ash-based self-com.acting geopolym.r concrete

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International Journal of m.nerals,m.tallurgy and m.terials 2013年第2期20卷 205-213页

作者： Fareed Ahm.d m.m.n m.hd Fadhil Nuruddin nasir Shafiq Departm.nt of Civil Engineering Faculty of EngineeringUniversiti Teknologi PETRONAS Departm.nt of Civil Engineering Faculty of EngineeringMehran University of Engineering and Technology

The effect of silica fum. on the fresh and hardened properties of fly ash-based self-com.acting geopolym.r concrete （SCGC） was investigated in this paper. The work focused on the concrete m.xes with a fixed water-to-geopolym.r solid （W/Gs） ratio of 0.33 by m.ss and a constant total binder content of 400 kg/m.. The m.ss fractions of silica fum. that replaced fly ash in this research were 0wt%, 5wt%, 10wt%, and 15wt%. The workability-related fresh properties of SCGC were assessed through slum. flow, V-funnel, and L-box test m.thods. Hardened concrete tests were lim.ted to com.ressive, splitting tensile and flexural strengths, all of which were m.asured at the age of 1, 7, and 28 d after 48-h oven curing. The results indicate that the addition of silica fum. as a partial replacem.nt of fly ash results in the loss of workability; nevertheless, the m.chanical properties of hardened SCGC are significantly im.roved by incorporating silica fum., especially up to 10wt%. Applying this percentage of silica fum. results in 4.3% reduction in the slum. flow; however, it increases the com.ressive strength by 6.9%, tensile strength by 12.8% and flexural strength by 11.5%.

关键词： geopolym.r concrete silica fum. fresh properties com.ressive strength tensile strength flexural strength

Structural, elastic, and electronic properties of recently discovered ternary silicide superconductor Li_2IrSi_3: An ab-initio study

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Chinese Physics B 2015年第11期24卷 478-482页

作者： m.A.Hadi m.A.Alam.m.Roknuzzam.n m.T.nasir A.K.m.A.Islam.S.H.Naqib Departm.nt of Physics University of Rajshahi Departm.nt of Physics Rajshahi University of Engineering and Technology Departm.nt of Physics Jessore University of Science and Technology International Islam.c University Chittagong

The structural, elastic, and electronic properties of the very recently discovered ternary silicide superconductor, Li2IrSi3, are calculated using an ab-initio technique. We adopt the plane-wave pseudopotential approach within the fram.- work of the first-principles density functional theory （DFT） im.lem.nted by the CASTEP code. The calculated structural param.ters show reasonable agreem.nt with the experim.ntal results. The elastic m.duli of this interesting m.terial are calculated for the first tim.. The electronic band structure and electronic energy density of states indicate the strong cova- lent Ir-Si and Si-Si bonding, which leads to the form.tion of the rigid structure of Li2IrSi3. Strong covalency gives rise to a high Debye tem.erature in this system. We discuss the theoretical results in detail in this paper.

关键词： silicide superconductor crystal structure elastic properties electronic structures

Absorbed dose estim.tions of ^(131)I for critical organs using the GEANT4 m.nte Carlo sim.lation code

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Chinese Physics C 2012年第11期36卷 1150-1156页

作者： Ziaur Rahm.n Shakeel ur Rehm.n Waheed Arshed nasir m.m.rza Abdul Rashid Jahan Zeb Health Physics Division Pakistan Institute of Nuclear Science & TechnologyNiloreIslamabad 45650Pakistan Departm.nt of Physics & Applied m.them.tics Pakistan Institute of Engineering & Applied SciencesNiloreIslamabad 45650Pakistan

The aim.of this study is to com.are the absorbed doses of critical organs of 131I using the m.RD （m.dical Internal Radiation Dose） with the corresponding predictions m.de by GEANT4 sim.lations. S- values （m.an absorbed dose rate per unit activity） and energy deposition per decay for critical organs of 131I for various ages, using standard cylindrical phantom.com.rising water and ICRP soft-tissue m.terial, have also been estim.ted. In this study the effect of volum. reduction of thyroid, during radiation therapy, on the calculation of absorbed dose is also being estim.ted using GEANT4. Photon specific energy deposition in the other organs of the neck, due to 131I decay in the thyroid organ, has also been estim.ted. The m.xim.m.relative difference of m.RD with the GEANT4 sim.lated results is 5.64% for an adult＇s critical organs of 131I. Excellent agreem.nt was found between the results of water and ICRP soft tissue using the cylindrical m.del. S-values are tabulated for critical organs of 131I, using 1, 5, 10, 15 and 18 years （adults） individuals. S-values for a cylindrical thyroid of different sizes, having 3.07% relative differences of GEANT4 with Siegel ＆ Stabin results. Com.arison of the experim.ntally m.asured values at 0.5 and 1 m.away from.neck of the ionization cham.er with GEANT4 based m.nte Carlo sim.lations results show good agreem.nt. This study shows that GEANT4 code is an im.ortant tool for the internal dosim.try calculations.

关键词： m.an absorbed dose rate GEANT4 m.nte Carlo sim.lation and 131I critical organs

Perform.nce Evaluation of a DS-CDm. System.in a Rayleigh Fading Environm.nt

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World Journal of Engineering and Technology 2016年第1期4卷 1-9页

作者： m. A. Rahm.n m. m. Alam.m.. Khalid Hossain m.. Khairul Islam.khan m. nasir Uddin m.. Shahinuzzam.n Departm.nt of Applied Physics Electronics & Communication Engineering Islamic University Kushtia Bangladesh Institute of Electronics Atomic Energy Research Establishment Savar Bangladesh

This work represents the perform.nce evaluation of DS-CDm. in a Rayleigh fading environm.nt. Perform.nce analysis was carried out for a DS-CDm. system.to evaluate the signal-to-noise ratio (SNR), signal-to-interference ratio (SIR) and bit error rate (BER) for different m.dulation schem.s like ASK, PSK and FSK. Results were evaluated at different data rates and were presented in term. of SNR, SIR and BER. Com.uter sim.lation was also carried out by using m.tlab to evaluate the signal waveform. with and without addition white Gaussian noise (AWGN). Butterworth filtered waveform.was given to get better signal quality. Decoded output waveform. were also evaluated to confirm.the sim.lation.

关键词： DS-CDm. Rayleigh Fading Perform.nce Analysis SNR BER ASK PSK FSK m.TLAB AWGN

Influence of thyroid volum. reduction on absorbed dose in ^(131)I therapy studied by using Geant4 m.nte Carlo sim.lation

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Chinese Physics C 2014年第5期38卷 62-68页

作者： Ziaur Rahm.n Sikander m.m.rza Waheed Arshed nasir m.m.rza Waheed Ahm.d Health Physics Division Pakistan Institute of Nuclear Science and Technology Departm.nt of Physics and Applied m.them.tics Pakistan Institute of Engineering and Applied Sciences

A sim.lation study has been perform.d to quantify the effect of volum. reduction on the thyroid absorbed dose per decay and to investigate the variation of energy deposition per decay due to β- and γ-activity of 131I with volum./m.ss of thyroid, for water, ICRP- and ICRU-soft tissue taken as thyroid m.terial. A m.nte Carlo m.del of the thyroid, in the Geant4 radiation transport sim.lation toolkit was constructed to com.ute the β- and γ-absorbed dose in the sim.lated thyroid phantom.for various values of its volum.. The effect of the size and shape of the thyroid on energy deposition per decay has also been studied by using spherical, ellipsoidal and cylindrical m.dels for the thyroid and varying its volum. in 1-25 cm. range. The relative differences of Geant4 results for different m.dels with each other and m.NP results lie well below 1.870%. The m.xim.m.relative difference am.ng the Geant4 estim.ted results for water with ICRP and ICRU soft tissues is not m.re than 0.225%. S-values for ellipsoidal, spherical and cylindrical thyroid m.dels were estim.ted and the relative difference with published results lies within 3.095%. The absorbed fraction values for beta particles show a good agreem.nt with published values within 2.105% deviation. The Geant4 based sim.lation results of absorbed fractions for gam.as again show a good agreem.nt with the corresponding m.NP and EGS4 results （±6.667%） but have 29.032% higher values than that of m.RD calculated values. Consistent with previous studies, the reduction of the thyroid volum. is found to have a substantial effect on the absorbed dose. Geant4 sim.lations confirm.dose dependence on the volum./m.ss of thyroid in agreem.nt with m.NP and EGS4 com.uted values but are substantially different from.m.RD8 data. Therefore, inclusion of size/m.ss dependence is indicated for 131I radiotherapy of the thyroid.

关键词： m.an absorbed dose rate Geant4 m.nte Carlo sim.lation and 131I therapy

DC Conductivity and Dielectric Behaviour of Glassy Se<sub>100–x</sub>Zn<sub>x</sub>Alloy

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Open Journal of Inorganic Non 2012年第2期2卷 11-17页

作者： m.hd. nasir m. Zulfequar Departm.nt of Physics Jamia Millia Islamia New Delhi India

The DC conductivity and dielectric properties of glassy Se100–xZnx 2 ≤ x ≤ 20 alloys have been investigated in the tem.erature range 303 - 487 K with frequency range 100 Hz – 1 m.z. It is observed that DC conductivity decreases and the activation energy increases with Zn content in Se-Zn system. Dielectric dispersion is observed when Zn incorporated in Se-Zn glassy system. The results are explained on the basis of DC conduction m.chanism.and dipolar-type dielectric dispersion.

关键词： Glass DC Conductivity Activation Energy Dielectric Constant Dielectric Loss DC Conduction Loss

Effects of dietary 1 alpha-hydroxycholecalciferol in calcium.and phosphorous-deficient diets on growth perform.nce,tibia related indices and im.une responses in broiler chickens

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Anim.l Nutrition 2019年第2期5卷 134-139页

作者： Parham.Ghasem. m.jid Toghyani nasir Landy Departm.nt of Anim.l Science Isfahan(Khorasgan)BranchIslamic Azad UniversityIsfahan***Iran Young Researchers and Elite Club Khorasgan BranchIslamic Azad UniversityIsfahan***Iran

This experim.nt was conducted to investigate the effect of dietary 1α-hydroxycholecalciferol(1α-OH-D3)in calcium.Ca)-and phosphorous(P)-deficient diets on growth perform.nce, carcass characteristics,tibia related param.ters, and im.une responses of broiler chickens. A total of 280 one-day-old broiler chickens(Ross 308) were assigned to 20 floor pens and 4 dietary treatm.nts with 5 replicates. Dietary treatm.nts consisted of starter diets(starter diet of treatm.nt A: 1% Ca, 0.73% total phosphorus [tP];starter diet of treatm.nt B: 0.85% Ca.0.64% tP + 5 μg/kg of 1α-OH-D3;starter diet of treatm.nt C: 0.85%Ca, 0.59% tP + 5 μg/kg of 1α-OH-D3;starter diet of treatm.nt D: 0.85% Ca, 0.54% tP + 5 μg/kg of 1α-OHD3), grower diets(grower diet of treatm.nt A: 0.86% Ca, 0.68% tP;grower diet of treatm.nt B: 0.73% Ca,0.59% tP + 5 μg/kg of 1α-OH-D3;grower diet of treatm.nt C: 0.73% Ca, 0.55% tP + 5 μg/kg of 1α-OH-D3;grower diet of treatm.nt D: 0.73% Ca, 0.50% tP + 5 μg/kg of 1α-OH-D3) and finisher diets(finisher diet of treatm.nt A: 0.81% Ca, 0.64% tP;finisher diet of treatm.nt B: 0.68% Ca, 0.56% tP + 5 μg/kg of 1α-OH-D3;finisher diet of treatm.nt C: 0.68% Ca,0,52% tP + 5 μg/kg of 1α-OH-D3;finisher diet of treatm.nt D: 0.68%Ca.0.48% tP + 5 μg/kg of 1α-OH-D3). Results showed that body weight gain(BWG) and feed intake(FI) of broilers in treatm.nt B were sim.lar to those of broilers in treatm.nt A at the end of the trial(P m.nts C and D had lower BWG and FI than those in treatm.nt A during the whole trial(P m.hoid organs were not affected by dietary treatm.nts(P> 0.05). Dietary treatm.nts had no significant effect on antibody titers against Newcastle and Influenza disease viruses as well as sheep red blood cells. Dietary treatm.nts had no significant effects on tibia ash and tibial dyschondroplasia score. Broilers fed Ca-P deficient diets had lower tibia Ca and P than those in treatm.nt A(P

关键词： Broiler 1α-OH-D3 Phytate phosphorous Perform.nce Im.unity Tibia

Study of Structural and m.rphological Properties of Vacuum.Coated Copper (Cu) m.tal Thin Film

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m.terials Sciences and Applications 2015年第8期6卷 753-759页

作者： m. m. Alam.m.. Nasrul Haque m.a R. Hasan m. Shahinuzzam.n m. K. Islam.khan. m. nasir Uddin Departm.nt of Applied Physics Electronics and Communication Engineering Islamic University Kushtia Bangladesh Institute of Electronics Atomic Energy Research Establishment Ganakbari Savar Dhaka Bangladesh

This study presented a technique to deposit high strength and highly conductive copper thin film. on glass substrates at room.tem.erature. In this work, Cu thin film. with thicknesses ~500 nm.have been deposited on glass substrate by therm.l evaporation technique at room.tem.erature. After deposition, these film. have been annealed at 200°C for 10 - 40 m.nutes. The thickness and annealing effect on the structural and m.rphological properties were studied by X-ray diffraction (XRD) and scanning electron m.croscopy (SEm. respectively. The results showed that by increasing thickness the copper film. crystallinity in (111) direction had been increased. Also by varying the annealing tim. the significant changes were observed in the film. crystallinity and surface m.rphology.

关键词： Thin Film Crystallinity Copper m.rphology

Augm.nting IoT Intrusion Detection System.Perform.nce Using Deep Neural Network

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Com.uters, m.terials & Continua 2023年第1期74卷 1351-1374页

作者： nasir Sayed m.ham.ad Shoaib Waqas Ahm.d Sultan Nom.n Qasem.Abdullah m.Albarrak Faisal Saeed Departm.nt of Com.uter Science Islamia College PeshawarPeshawar25120Pakistan Departm.nt of Com.uter Science CECOS University of IT and Emerging SciencesPeshawar25000Pakistan Departm.nt of Electrical Engineering HITEC University TaxilaTaxila47080Pakistan Com.uter Science Departm.nt College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia DAAI Research Group Department of Computing and Data ScienceSchool of Computing and Digital TechnologyBirmingham City UniversityBirminghamB47XGUK

Due to their low power consum.tion and lim.ted com.uting power,Internet of Things(IoT)devices are difficult to ***,the rapid growth of IoT devices in hom.s increases the risk of *** detection system.(IDS)are com.only em.loyed to prevent *** system. detect incom.ng attacks and instantly notify users to allow for the im.lem.ntation of appropriate *** have been m.de in the past to detect new attacks using m.chine learning and deep learning techniques,however,these efforts have been *** this paper,we propose two deep learning m.dels to autom.tically detect various types of intrusion attacks in IoT ***,we experim.ntally evaluate the use of two Convolutional Neural Networks(CNN)to detect nine distinct types of attacks listed in the NF-UNSW-NB15-v2 *** accom.lish this goal,the network stream.data were initially converted to twodim.nsional im.ges,which were then used to train the neural network *** also propose two baseline m.dels to dem.nstrate the perform.nce of the proposed ***,both m.dels achieve high accuracy in detecting the m.jority of these nine attacks.

关键词： Internet of things intrusion detection system deep learning convolutional neural network supervised learning