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A Double Threshold Energy Detection-Based Neural Network for Cognitive Radio Networks

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Computer Systems Science & Engineering 2023年第4期45卷 329-342页

作者： Nada m.Elfatih Elmustafa Sayed Ali maha Abdelhaq Raed Alsaqour rashid A.Saeed Department of Electrical and Electronics Engineering Red Sea UniversityPort Sudan33311Sudan Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Information Technology College of Computing and InformaticsSaudi Electronic UniversityRiyadh93499Saudi Arabia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Electronics Engineering Sudan University of Science and TechnologyKhartoum11111Sudan

In cognitive radio networks(CoR),the performance of cooperative spectrum sensing is improved by reducing the overall error rate or maximizing the detection *** optimization methods are usually used to optimize the number of user-chosen for cooperation and the threshold ***,these methods do not take into account the effect of sample size and its effect on improving CoR *** general,a large sample size results in more reliable detection,but takes longer sensing time and increases ***,the locally sensed sample size is an optimization ***,optimizing the local sample size for each cognitive user helps to improve CoR *** this study,two new methods are proposed to find the optimum sample size to achieve objective-based improved(single/double)threshold energy detection,these methods are the optimum sample size N^(*)and neural networks(NN)*** the evaluation,it was found that the proposed methods outperform the traditional sample size selection in terms of the total error rate,detection probability,and throughput.

关键词： Cognitive radio spectrum sensing energy detection double threshold neural network machine learning optimization quality of service

Absorbed dose estimations of ^(131)I for critical organs using the GEANT4 monte Carlo simulation code

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

作者： Ziaur Rahman Shakeel ur Rehman Waheed Arshed Nasir m mirza Abdul rashid Jahan Zeb Health Physics Division Pakistan Institute of Nuclear Science & TechnologyNiloreIslamabad 45650Pakistan Department of Physics & Applied mathematics Pakistan Institute of Engineering & Applied SciencesNiloreIslamabad 45650Pakistan

The aim of this study is to compare the absorbed doses of critical organs of 131I using the mIRD （medical Internal Radiation Dose） with the corresponding predictions made by GEANT4 simulations. S- values （mean absorbed dose rate per unit activity） and energy deposition per decay for critical organs of 131I for various ages, using standard cylindrical phantom comprising water and ICRP soft-tissue material, have also been estimated. In this study the effect of volume reduction of thyroid, during radiation therapy, on the calculation of absorbed dose is also being estimated using GEANT4. Photon specific energy deposition in the other organs of the neck, due to 131I decay in the thyroid organ, has also been estimated. The maximum relative difference of mIRD with the GEANT4 simulated results is 5.64% for an adult＇s critical organs of 131I. Excellent agreement was found between the results of water and ICRP soft tissue using the cylindrical model. 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. Comparison of the experimentally measured values at 0.5 and 1 m away from neck of the ionization chamber with GEANT4 based monte Carlo simulations results show good agreement. This study shows that GEANT4 code is an important tool for the internal dosimetry calculations.

关键词： mean absorbed dose rate GEANT4 monte Carlo simulation and 131I critical organs

Spatio-temporal variation of land surface temperature and temperature lapse rate over mountainous Kashmir Himalaya

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Journal of mountain Science 2018年第3期15卷 563-576页

作者： Shakil Ahmad ROmSHOO mohammd RAFIQ Irfan rashid Department of Earth Sciences University of Kashmir

In this study, Land Surface Temperature(LST) and its lapse rate over the mountainous Kashmir Himalaya was estimated using mODIS data and correlated with the observed in-situ air temperature(Tair) data. Comparison between the mODIS LST and Tair showed a close agreement with the maximum error of the estimate ±1°C and the correlation coefficient >0.90. Analysis of the LST data from 2002-2012 showed an increasing trend at all the selected locations except at a site located in the southeastern part of Kashmir valley. Using the GTOPO30 DEm, mODIS LST data was used to estimate the actual temperature lapse rate(ATLR) along various transects across Kashmir Himalaya, which showed significant variations in space and time ranging from 0.3°C to 1.2°C per 100 m altitude change. This observation is at variance with the standard temperature lapse rate(STLR) of 0.65°C used universally in most of the hydrological and other land surface models. Snowmelt Runoff model(SRm) was used to determine the efficacy of using the ATLR for simulating the stream flows in one of the glaciated and snow-covered watersheds in Kashmir. The use of ATLR in the SRm model improved the R2 between the observed and predicted streamflows from 0.92 to *** is hoped that the operational use of satellite-derived LST and ATLR shall improve the understanding and quantification of various processes related to climate, hydrology and ecosystem in the mountainous and data-scarce Himalaya where the use of temperature and ATLR are critical parameters for understanding various land surface and climate processes.

关键词： mODIS Land Surface Temperature Lapse Rate DEm Snowmelt Runoff model Himalaya

Optical transmission in thin films of vanadium compounds

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Journal of Semiconductors 2014年第7期35卷 10-14页

作者： Kh.S.Karimov m.mahroof-Tahir m.Saleem N.Ahmad A.rashid GIK Institute of Engineering Sciences and Technology TopiDistrict SwabiKPK 23640Pakistan Physical Technical Institute of Academy of Sciences Rudaki Ave33Dushanbe 734025Tajikistan Saint Cloud State University 720 Fourth Avenue SouthSaint CloudMN 56301-4498USA Government College of Science Wahdat RoadLahore 54570Pakistan

Thin films of five vanadium compounds/composite：（1） VO2（3-fl）（3-fl = 3-Hydroxyflavone）, （2） VO（pbd）：（pbd = 1-Phenyl-l, 3-butadione）, （3） VO（dbm）2 （dbm = Dibenzoylmethane）, （4） VPc （Vanadyl Phthalocyanine） and （5） V2O5-PEPC （V2O5- poly-N-epoxypropylcarbazole composite）, were deposited by the dropcasting method from the solution in benzene. The transmittance-irradiance relationships were investigated and the transmission in the visible spectrum and optical images were obtained as well. It was found that the transmittance of the VO2（3-fl）, VO（pbd）2, VO（dbm）2 and VPc, was practically independent of the irradiance; whereas the transmittance of V2O5-PEPC decreased by 4% for thin and 9% for thick films with an increase of the irradiance.

关键词： vanadium compound/composite semiconductor thin film transmittance irradiance

Dynamic characteristics of nanoindentation in Ni:A molecular dynamics simulation study

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Chinese Physics B 2012年第11期21卷 367-372页

作者： muhammad Imran Fayyaz Hussain muhammad rashid S.A.Ahmad Department of Physics Simulation Lab Islamia University of Bahawalpur 63100Pakistan Department of Physics National University of Singapore 117542Singapore

In this work, three-dimensional molecular dynamics simulation is carried out to elucidate the nanoindentation behaviour of single crystal Ni. The substrate indenter system is modelled using hybrid interatomic potentials including the manybody potential （embedded atom method） and two-body morse potential. The spherical indenter is chosen, and the simulation is performed for different loading rates from 10 m/s to 200 m/s. Results show that the maximum indentation load and hardness of the system increase with the increase of velocity. The effect of indenter size on the nanoindentation response is also analysed. It is found that the maximum indentation load is higher for the large indenter whereas the hardness is higher for the smaller indenter. Dynamic nanoindentation is carried out to investigate the behaviour of Ni substrate to multiple loading-unloading cycles. It is observed from the results that the increase in the number of loading unloading cycles reduces the maximum load and hardness of the Ni substrate. This is attributed to the decrease in recovery force due to defects and dislocations produced after each indentation cycle.

关键词： indentation nanocrystalline loading-unloading dislocation

Analysis and Numerical Computations of the multi-Dimensional,Time-Fractional model of Navier-Stokes Equation with a New Integral Transformation

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Computer modeling in Engineering & Sciences 2023年第9期136卷 3025-3060页

作者： Yuming Chu Saima rashid Khadija Tul Kubra mustafa Inc Zakia Hammouch m.S.Osman Department of mathematics Huzhou UniversityHuzhouChina Department of mathematics Government College UniversityFaisalabadPakistan Department of mathematics Firat UniversityElazigTurkey medical Research China Medical UniversityTaichungTaiwan Division of Applied mathematics Thu Dau Mot UniversityThu Dau MotVietnam Department of mathematics Faculty of ScienceCairo UniversityGiza12613Egypt

The analytical solution of the multi-dimensional,time-fractional model of Navier-Stokes equation using the triple and quadruple Elzaki transformdecompositionmethod is presented in this *** aforesaidmodel is analyzed by employing Caputo fractional *** deliberated three stimulating examples that correspond to the triple and quadruple Elzaki transform decomposition methods,*** findings illustrate that the established approaches are extremely helpful in obtaining exact and approximate solutions to the *** exact and estimated solutions are delineated via numerical *** proposed analysis indicates that the projected configuration is extremely meticulous,highly efficient,and precise in understanding the behavior of complex evolutionary problems of both fractional and integer order that classify affiliated scientific fields and technology.

关键词： Caputo derivative Elzaki transform time-fractional Navier-Stokes equation decomposition method

A journey towards shared governance: status and prospects for collaborative management in the protected areas of Bangladesh

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Journal of Forestry Research 2013年第3期24卷 599-605,602-605页

作者： A. Z. m. manzoor rashid Donna Craig Sharif Ahmed mukul Niaz Ahmed Khan Environmental Law School of Law University of Western SydneyAustralia Department of Forestry and Environmental Science Shahjalal University of Science and TechnologySylhet Bangladesh School of Agriculture and Food Sciences The University of QueenslandAustralia Department of Development Studies University of DhakaBangladesh

Establishment of Protected Areas （PAs）, in the face of rapid deforestation, forest degradation and climate change has been one of the key efforts in conservation of biodiversity worldwide in recent times. While Bangladesh has gained a degree of prominence in the world for its successful social forestry programs, the concept of collaborative pro- tected area management is rather new in the country, initiated in 2004 by the Bangladesh Forest Department in five PAs with financial assistance from USAID. Based on empirical evidence from three of the pilot PAs, we examined the achievements and associated challenges and prospects for co-management. Our fieldwork revealed a number of challenges faced by co-management institutions：（1） institutions were dominated by the elite group, overshadowing the voice of the community people; （2） mutual trust and collective performance are key to good governance but had not taken root in the PAs; （3） encroachment onto forest land and subsequent conversion to agriculture remained a serious problem that discouraged forest-dependent people from participating actively in co-management initiatives; （4） legal provisions （including acts, rules and policies） were not clearly and adequately disseminated and understood at the community level; （5） there remained a degree of ambiguity regarding the roles and responsibilities of forest department （FD） and co-management committees （CmC） in field operations, and this was not enhancing transparency and accountability of the overall initiative; （6） the long-term sustainability of co-management institutions was another major concern, as the local intuitional structure was still in a nascent stage, and provisioning of resources （either internally or externally） remained somewhat uncertain. We offer recommendations for improve- ment.

关键词： protected area co-management Nishorgo IPAC govern-ance

Synthesis, characterization and electrochemical evaluation of anticorrosion property of a tetrapolymer for carbon steel in strong acid media

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Chinese Journal of Chemical Engineering 2019年第4期27卷 965-978页

作者： Shamsuddeen A.Haladu Saviour A.Umoren Shaikh A.Ali moses m.Solomon Abdul-rashid I.mohammed Department Basic Sciences and Humanities College of Engineering Imam Abdulrahman Bin Faisal University Dammam 31451 Saudi Arabia Centre of Research Excellence in Corrosion Research Institute King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia Department of Chemistry King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia Centre for Engineering Research Research Institute King Fahd University of Petroleum and Minerals Dhahran 31261 Saudi Arabia

A novel tetrapolymer(TP) consisting of carboxylate, sulphonate, phosphonate and sulfur dioxide based comonomers was synthesized using Butler cyclopoymerization technique. The synthesized tetrapolymer was characterized using FTIR,1H-NmR,13CNmR and elemental analysis. The performance of the tetrapolymer as a corrosion inhibitor for St37 carbon steel in 15% HCl and 15% H2SO4 acid media was assessed using electrochemical impedance spectroscopy(EIS), linear polarization resistance(LPR), potentiodynamic polarization(PDP) and electrochemical frequency modulation(EFm) techniques. The influence of addition of a small amount of KI on the corrosion inhibition efficiency of TP was also assessed. Results obtained showed that the tetrapolymer moderately inhibited the corrosion of St37 steel in the acid media with protection efficiency of 79.5% and 61.1% at the optimum concentration of 1000 mg·L^-1 studied in HCl and H2SO4 media respectively. On addition of 5 mmol·L^-1 KI to the optimum tetrapolymer concentration, the protection efficiency was upgraded to 90.6% and 93.5% in HCl and H2SO4 environment, respectively. The enhanced performance of the polymer in the presence of KI is due to synergistic action deduced from synergism parameter(S1) which was found to be greater than *** tetrapolymer afforded the corrosion inhibition of St37 steel in the acid media by virtue of adsorption of the polymer molecules on the steel surface which was confirmed by ATR-FTIR analysis of the adsorbed film extracted from the steel surface. TP + KI formed complex with St37 steel surface in H2SO4 solution but not in HCl solution.

关键词： Tetrapolymer metal Acid corrosion Corrosion inhibition Adsorption Synergism

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Anthrax:an update

Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 496-501页

作者： Kamal Sm.rashid AKm m Bakar mA Aliad mA Department of medicine Khulna Medical College Department of Paediatrics Khulna Medical College Department of Gastroenterology khulna Medical College

Anthrax is a zoonotic disease caused by Bacillus *** is potentially fatal and highly contagious *** arc the natural *** acquire the disease incidentally by contact with infected animal or animal *** the 18th century an epidemic destroyed approximately half of the sheep in *** 1900 human inhalational anthrax occured sporadically in the United *** 1979 an outbreak of human anthrax occured in Sverdlovsk of Soviet *** continued to represent a world wide *** incidence of the disease has decreased in developed countries as a result of vaccination and improved industrial *** anthrax clinically presents in three forms,***,gastrointestinal and *** 95%of human anthrax is cutaneous and 5%is *** anthrax is very rare(less than 1%).Inhalational form is used as a biological warefare agent. Penicillin,ciprofloxacin(and other quinolones),doxicyclin,ampicillin,***, clarithromycin,vancomycin,chloramphenicol,rifampicin are effective antimicrobials. Antimicrobial therapy for 60 days is *** anthrax vaccine is available. Administration of anti-protective antigen(PA) antibody in combination with ciprofloxacin produced 90%-100%*** combination of CPG-adjuvanted anthrax vaccine adsorbed(AVA) plus dalbavancin significantly improved survival.

关键词： Anthrax Bacillus anthracis Zoonotic disease Contagious disease Cutaneous anthrax Inhalational anthrax Gastrointestinal anthrax Human anthrax