检索结果-南通市图书馆

The effect of replacing pnictogen elements on the physical properties of Srmg_2X_2(X=N,P,As,Sb,Bi) Zintl compounds

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2018年第4期27卷 369-375页

作者： G murtaza Abdul Ahad Khan m Yaseen A Laref naeem Ullah Inayat ur Rahman materials modelling Labortary Department of PhysicsIslamia College University Department of Physics University of the Peshawar Department of Physics University of AgricultureFaisalabad Department of Physics and Astronomy College of ScienceKing Saud University Department of Physics City University of Hong Kong

The effect of replacing the anion from N to Bi down the group in the periodic table is investigated on Srmg2X2（X = N,P,As,Sb,Bi）.A full potential linearized augmented plane wave plus local orbitals method is used along with different exchange–correlation potentials to obtain the lattice constants,phonons,electronic,and optical properties of the Sr mg2X2（X = N,P,As,Sb,Bi） Zintl compounds.A good agreement is achieved and our calculations are validated by previous experimental and theoretical *** compounds have shown stable dynamical behavior with gamma centered longitudinal response having no imaginary *** band structures reveal the semiconducting nature of the *** Pnictogen（X）-p state contributed mainly in the valence band and the Sr-d state forms the conduction of the *** charge transfer and low overlapping of the atomic densities indicates the preferable ionic bonding character of these *** the optical properties,real and imaginary parts of dielectric function,complex refractive index,birefringence,reflectivity,and optical conductivity are *** compounds can be utilized in the optical and optoelectronic devices.

关键词： Zintl compounds band structure optical response

Structural and dielectric properties of doped ferrite nanomaterials suitable for microwave and biomedical applications

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:materials International 2015年第5期25卷 419-424页

作者： Imran Sadiq Shahzad Naseem muhammad naeem Ashiq m.A.Khan Shanawer Niaz m.U.Rana Centre of Excellence in Solid State Physics University of the Punjab Institute of Chemical Sciences Bahauddin Zakariya University Department of Physics BUITEMS 4. Department of Physics University of Sargodha

The sol-gel auto-combustion method was adopted to synthesize nanomaterials of single-phase X-type hexagonal ferrites with the composition of Sr;Gd;Ni;Fe;Cd;O;（x=0.00,0.02,0.04,0.06,0.08,0.10 and y = 0,0.1,0.2,0.3,0.4,0.5）.The structural properties were carried out by XRD analysis and the lattice parameters show variation with the doping of *** average particle size measured by TEm was in the range of 8-10 nm which is beneficial in obtaining suitable signal-to-noise ratio in recording media and biomedical *** room temperature resistivity enhanced with the increase of the dopant *** increase in resistivity indicates that the synthesized materials can be considered good for the formation of the multilayer chip inductors（mLCIs） as well as for the reduction of eddy current *** dielectric constant decreased with the increase in the frequency which is the general reported trend of the hexagonal ferrites and can be explained on the basis of Koop’s theory and maxwell-Wagner *** abnormal dielectric behavior indicates the formation of small polarons in the *** maximum value of tangent loss at low frequencies reflects the application of these materials in medium frequency devices（mF）.

关键词： Sol–gel Nanocrystalline materials Thermal properties Electrical properties Dielectric properties

Elemental profile of black shales

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal Of Geochemistry 2011年第2期30卷 217-219页

作者： KASHIF naeem WASIm Yawar TARIQ m.Bhatti BASHIR mohammad Central Analytical Facility Division Pakistan Institute of Nuclear Science and TechnologyP.O.NiloreIslamabad 45650Pakistan Pakistan Institute of Engineering and Applied Sciences P.O.NiloreIslamabad 45650Pakistan

A black shale sample collected from the Chimiari site(Tarbela) was analyzed for elemental *** coupled plasma-optical emission spectrometry(ICP-OES) was employed to determine major and trace elements in the *** analysis was accomplished for the black shales,which was better than 2.0%.Result shows that the shales are very rich in Ca(25439 μg·g-1),Fe(13933 μg·g-1),Ti(6932 μg·g-1),Al(5993 μg·g-1) and K(2730 μg·g-1).

关键词：黑页岩 ICP-OES 踪迹元素

An Efficient Proxy Blind Signcryption Scheme for IoT

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2022年第3期70卷 4293-4306页

作者： Aamer Khan Insaf Ullah Fahad Algarni muhammad naeem m.Irfan Uddin muhammad Asghar Khan Department of Information Technology Abbottabad University of Science and TechnologyAbbotabadPakistan Hamdard Institute of Engineering and Technology Islamabad44000Pakistan College of Computing and Information Technology University of BishaBishaSaudi Arabia Institute of Computing Kohat University of Science and TechnologyKohatPakistan

Recent years have witnessed growing scientific research interest in the Internet of Things(IoT)technologies,which supports the development of a variety of applications such as health care,Industry 4.0,agriculture,ecological data management,and other various *** utilizes the Internet as a prime medium of communication for both single documents as well as multi-digital ***,due to the wide-open nature of the Internet,it is important to ensure the anonymity,untraceably,confidentiality,and unforgeability of communication with efficient computational complexity and low *** designed a light weight and secure proxy blind signcryption for multi-digital messages based on a hyperelliptic curve(HEC).Our results outperform the available schemes in terms of computational cost and communication *** designed scheme also has the desired authentication,unforgeability of warrants and/or plaintext,confidentiality,integrity,and blindness,***,our scheme is more suitable for devices with low computation power such as mobiles and tablets.

关键词： Proxy signcryption multi-digital-documents proxy blind signcryption hyperelliptic curve IoT

FirstPrincipleCalculations of the Ground and Excited State Properties of RbPbF_(3)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第9期30卷 128-131页

作者： Hayatullah G.murtaza R.Khenata S.naeem m.N.Khalid S.mohammad materials modeling Lab Hazara UniversityMansehraPakistan materials modeling Lab Department of PhysicsIslamia College UniversityPeshawarPakistan LPQ3m Laboratory Institute of Science and TechnologyUniversity of MascaraAlgeria Department of Physics and Astronomy King Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

Structural,elastic,electronic,chemical bonding and optical properties of the cubic RbPbF 3 compound under pres-sure are studied using a highly accurate state-of-the-art full potential linearized augmented plane wave *** exchange correlation effects are included through the generalized gradient and modified Becke–Johnson ex-change *** lattice constant and band gap of the cubic RbPbF 3 decreases with enhanced *** 3 is brittle,elastically anisotropic,and a direct bandgap *** optical properties such as refractive index𝑜(ω),extinction coefficient𝑙(ω),reflectivity𝑆(ω),and optical conductivity𝜏(ω)are predicted.

关键词： potential. material. method.

On Hiding Secret Information in medium Frequency DCT Components Using Least Significant Bits Steganography

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer modeling in Engineering & Sciences 2019年第3期118卷 529-546页

作者： Sahib Khan m A Irfan Arslan Arif Syed Tahir Hussain Rizvi Asma Gul muhammad naeem Nasir Ahmad Department of Electronics and Telecommunications Politecnico di Torino10129 TorinoItaly Department of Computer Engineering University of LahorePakistan Department of Statistics Shaheed Benazir Bhutto Women University PeshawarPakistan Department of Computer Science University of PeshawarPakistan Department of Electronic and Electrical Engineering Loughborough UniversityUnited Kingdom

This work presents a new method of data hiding in digital images,in discrete cosine transform *** proposed method uses the least significant bits of the medium frequency components of the cover image for hiding the secret information,while the low and high frequency coefficients are kept *** unaltered low frequency DCT coefficients preserves the quality of the smooth region of the cover image,while no changes in the high DCT coefficient preserve the quality of the *** the medium frequency components have less contribution towards energy and image details,so the modification of these coefficients for data hiding results in high quality stego *** distortion due to the changes in the medium frequency coefficients is insignificant to be detected by the human visual *** proposed methods demonstrated a hiding capacity of 43:11%with the stego image quality of a peak signal to the noise ration of 36:3 dB,which is significantly higher than the threshold of 30 dB for a stego image *** proposed technique is immune to steganalysis and has proved to be highly secured against both spatial and DCT domain steganalysis techniques.

关键词： DCT steganography image processing information security data hiding steganalyisis

Earthquake Risk Assessment Approach Using multiple Spatial Parameters for Shelter Demands

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, materials & Continua 2022年第2期70卷 3763-3780页

作者： Wenquan Jin naeem Iqbal Hee-Cheal Kang Dohyeun Kim Big Data Research Center Jeju National UniversityJeju63243Korea Department of Computer Engineering Jeju National UniversityJeju63243Korea Infomind Jeju63243Korea

The earthquake is considered one of the most devastating disasters in any area of the world due to its potentially destructive *** on the various earthquake-related parameters,the risk assessment is enabled in advance to prevent future earthquake *** this paper,for providing the shelter space demands to reduce the damage level and prevention costs,an earthquake risk assessment approach is proposed for deriving the risk index based on multiple spatial parameters in the gridded *** proposed assessment approach is comprised of pre-processing,methodologymodel,and data *** risk index model derives the earthquake risk index by multiple spatial parameters including indexes of earthquake,danger,shelter,and building for blocks in the quantitative gridded *** parameters are provided based onmathematicalmodels and combinedwith the risk index that presents the earthquake risk assessment result for each ***,the gridding approach is proposed to provide the elements of the risk assessment area that are used in the spatial *** gridded map is developed for the selected area to visualize risk index parameters associated with each risk *** on the derived result of the proposed earthquake risk indexmodel,emergency shelter requirements are provided according to the risk index for each location,which supports safety measures in advance to prevent future earthquake disasters.

关键词： Risk analysis risk index earthquake shelter demand data analysis

Influence of Y^(3+),Yb^(3+),Gd^(3+) cations on structural and electromagnetic properties of CuFe_(2)O_(4) nanoferrites prepared via one step sol-gel method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第10期39卷 1224-1231,I0003页

作者： Aleena Kiran majid Niaz Akhtar muhammad Yousaf Khalid mujassam Batoo Omar mAldossary Salman naeem Khan Department of Physics COMSATS University IslamabadLahore CampusDefence Road Off RaiwindLahore54000Pakistan Department of Physics Mohammad Nawaz Sharif University of Engineering and TechnologyMultan60000Pakistan School of Energy and Environment Southeast UniversityNo2 Si Pai LouNanjing 210096China King Abdullah Institute for Nanotechnology King Saud UniversityP.O.Box 2455Riyadh11458Saudi Arabia Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box-2455Riyadh11451Saudi Arabia micro-mm Wave Laboratory(m2L) Department of PhysicsCOMSATS University IslamabadLahore CampusDefence Road Off RaiwindLahore54000Pakistan

Rare earths(REs) play a key role in distorting spinel structure by creating some defects at the lattice sites and make them suitable for magnetodielectric *** the present study,the nanoferrites of CuRE0.02Fe1.98O4,where REs=Y^(3+),Yb^(3+),Gd^(3+),were prepared using one step sol-gel *** prepared samples are copper ferrite(CFO),yttrium doped copper ferrite(Y-CFO),ytterbium doped copper ferrite(Yb-CFO) and gadolinium doped copper ferrite(Gd-CFO),*** single-phase structure of all the REs doped nanoferrites was determined by X-ray diffraction(XRD) *** porosity,agglomerations and grain size of the REs doped copper ferrite were examined using field emission scanning electron microscopy(FESEm) *** transform infrared spectroscopy(FTIR)elaborates the phase formation and environmental effects on the REs doped nanoparticles(NPs).The recorded room temperature m-H loops from a vibrating sample magnetometer(VSm) elucidate the magnetic properties of the REs doped spinel *** magnetic saturation(ms) was calculated in the range of 23.08 to 51.78 emu/*** calculated coercivity values(272.6 to 705.60 Oe) confirm the soft magnetic behavior of REs doped copper ***,the electromagnetic and dielectric properties were assessed using a Vector network analyzer(VNA) from 1 to 6 *** permeability,permittivity,dielectric tangent loss and electric modulus of the REs doped spinel ferrites illustrate that the prepared NPs may be suitable for microwave and high frequency applications.

关键词： Rare earth elements Nanoparticles Spinel ferrites VSm VNA magnetodielectric applications

Dynamic channel estimation-aware routing protocol in mobile cognitive radio networks for smart IIoT applications

在线全文

学校读者我要写书评

暂无评论

Digital Communications and Networks 2023年第2期9卷 367-382页

作者： Qusay m.Salih md Arafatur Rahman A.Taufiq Asyhari muhammad Kamran naeem mohammad Patwary Ryan Alturki mohammed Abdulaziz Ikram Faculty of Computing Universiti Malaysia Pahang26300GambangPahangMalaysia School of Engineering Computing and Mathematical SciencesUniversity of WolverhamptonUK Data Science Program Monash UniversityIndonesiaand Birmingham City UniversityB47XGUK Department of Information Science College of Computer and Information SystemsUmm Al-Qura UniversitySaudi Arabia Computer Science Department Al Jumoum University CollegeUmm Al-Qura UniversitySaudi Arabia

Cognitive Radio Networks(CRNs)have become a successful platform in recent years for a diverse range of future systems,in particularly,industrial internet of things(IIoT)*** order to provide an efficient connection among IIoT devices,CRNs enhance spectrum utilization by using licensed ***,the routing protocol in these networks is considered one of the main problems due to node mobility and time-variant channel ***,the channel selection for routing protocol is indispensable in CRNs to provide an adequate adaptation to the Primary User(PU)activity and create a robust routing *** study aims to construct a robust routing path by minimizing PU interference and routing delay to maximize throughput within the IIoT ***,a generic routing framework from a cross-layer perspective is investigated that intends to share the information resources by exploiting a recently proposed method,namely,Channel Availability ***,a novel cross-layer-oriented routing protocol is proposed by using a time-variant channel estimation *** protocol combines lower layer(Physical layer and Data Link layer)sensing that is derived from the channel estimation ***,it periodically updates and stores the routing table for optimal route ***,in order to achieve higher throughput and lower delay,a new routing metric is *** evaluate the performance of the proposed protocol,network simulations have been conducted and also compared to the widely used routing protocols,as a *** simulation results of different routing scenarios demonstrate that our proposed solution outperforms the existing protocols in terms of the standard network performance metrics involving packet delivery ratio(with an improved margin of around 5–20%approximately)under varying numbers of PUs and cognitive users in mobile Cognitive Radio Networks(mCRNs).moreover,the cross-layer routing protocol successfully achiev

关键词： Channel selection Cross-layer design mobile cognitive radio networks Routing protocol IIoT applications