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Th-Shaped Tunable Multi-Band Antenna for Modern Wireless Applications

Computers, Materials & Continua 2023年第2期74卷 2517-2530页

作者： Wasi Ur Rehman Khan muhammad Fawad Khan muhammad Irfan Sadiq Ullah Naveed Mufti Usman Ali Rizwan Ullah Fazal muhammad Saifur Rahman Faisal Althobiani Mohammed Alshareef Mohammad E.Gommosani Department of Telecommunication Engineering University of Engineering and TechnologyMardanPakistan Electrical Engineering Department College of EngineeringNajran UniversityNajranSaudi Arabia Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Natural Science Department Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia

A compact,reconfigurable antenna supporting multiple wireless services with a minimum number of switches is found lacking in literature and the same became the focus and outcome of this *** was achieved by designing a Th-Shaped frequency reconfigurable multi-band microstrip planar antenna,based on use of a single switch within the radiating structure of the *** frequency bands(i.e.,2007–2501 MHz,3660–3983MHz and 9341–1046 MHz)can be operated with the switch in the ON switch *** the OFF state of the switch,the antenna operates within the 2577–3280MHz and 9379–1033MHz *** proposed antenna shows an acceptable input impedance match with Voltage Standing Wave Ratio(VSWR)less than *** peak radiation efficiency of the antenna is 82%.A reasonable gain is obtained from 1.22 to 3.31 dB within the operating bands is *** proposed antenna supports UniversalMobile Telecommunication System(UMTS)-1920 to 2170 MHz,Worldwide Interoperability and Microwave Access(WiMAX)/Wireless Broadband/(Long Term Evolution)LTE2500–2500 to 2690 MHz,Fifth Generation(5G)-2500/3500 MHz,Wireless Fidelity(Wi-Fi)/Bluetooth-2400 to 2480 MHz,and Satellite communication applications in X-Band-8000 to 12000 *** overall planar dimension of the proposed antenna is 40×*** antennawas designed,along with the parametric study,using Electromagnetic(em)simulation *** antenna prototype is fabricated for experimental validation with the simulated *** proposed antenna is low profile,tunable,lightweight,cheap to fabricate and highly efficient and hence is deemed suitable for use in modern wireless communication electronic devices.

关键词： Antenna design reconfigurable antenna satellite communication frequency bands

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Intelligent computing networks for nonlinear influenza-A epidemic model

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International Journal of Biomathematics 2023年第4期16卷 125-154页

作者： Nabeela Anwar muhammad Shoaib Iftikhar Ahmad Shafaq Naz Adiqa Kausar Kiani muhammad Asif Zahoor Raja Department of Mathematics University of Gujrat Punjab 50700 Pakistan Department of Mathematics COMSATS University Islamabad Attock Campus Attock 43600 Pakistan Future Technology Research Center National Yunlin University of Science and Technology 123 UniversityRoad Section 3 DouliouYunlin 64002TaiwanR.O.C.

The differential equations having delays take paramount interest in the research community due to their fundamental role to interpret and analyze the mathematical models arising in biological *** study deals with the exploitation of knack of artificial intelligence-based computing paradigm for numerical treatment of the functional delay differential systems that portray the dynamics of the nonlinear influenza-A epidemic model(IA-em)by implementation of neural network backpropagation with Levenberg-Marquardt scheme(NNBLMS).The nonlinear IA-em represented four classes of the population dynamics including susceptible,exposed,infectious and recovered *** referenced datasets for NNBLMS are assembled by employing the Adams method for sufficient large number of scenarios of nonlinear IA-em through the variation in the infection,turnover,disease associated death and recovery *** arbitrary selection of training,testing as well as validation samples of dataset are utilizing by designed NNBLMS to calculate the approximate numerical solutions of the nonlinear IA-em develop a good agreement with the reference *** proficiency,reliability and accuracy of the designed NNBLMS are further substantiated via exhaustive simulations-based outcomes in terms of mean square error,regression index and error histogram studies.

关键词： Functional delay differential systems nonlinear influenza-A epidemic model Adams method neural networks Levenberg-Marquardt scheme intelligent computing regression analysis

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Frequency-Agile WLAN Notch UWB Antenna for URLLC Applications

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Computers, Materials & Continua 2021年第5期67卷 2243-2254页

作者： Amir Haider MuhibUr Rahman Hamza Ahmad Mahdi NaghshvarianJahromi muhammad Tabish Niaz Hyung Seok Kim Department of Intelligent Mechatronics Engineering Sejong UniversitySeoul05006Korea Department of Electrical Engineering Polytechnique MontrealMontrealQC H3T 1J4Canada Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Department of Electrical and Computer Engineering McMaster UniversityHamilton ONL8S 4L8Canada

This paper introduces a compact dual notched UWB antenna with an independently controllable WLAN notched band integrated with fixed WiMAX *** proposed antenna utilizes a slot resonator placed in the main radiator of the antenna for fixed WiMAX band notch,while an inverted L-shaped resonator in the partial ground plane for achieving frequency agility within WLAN notched *** inverted L-shaped resonator is also loaded with fixed and variable capacitors to control and adjust the WLAN *** WLAN notched band can be controlled independently with a wide range of tunability without disturbing the WiMAX bandnotch *** by step design approach of the proposed antenna is discussed and the corresponding mathematical analysis of the proposed resonators are provided in both *** of the proposed antenna is performed utilizing commercially available 3D-em simulator,Ansoft High Frequency Structure Simulator(HFSS).The proposed antenna has high selectivity with experimental validation in terms of reflection coefficient,radiation characteristics,antenna gain,and percentage radiation *** corresponding measured frequency response of the input port corresponds quite well with the calculations and simulations in both *** proposed antenna is advantageous and can adjust according to the device requirements and be one of the attractive candidates for overlay cognitive radio UWB applications and URLLC service in 5G tactile *** proposed multifunctional antenna can also be used for wireless vital signs monitoring,sensing applications,and microwave imaging techniques.

关键词： WiMAX UWB lower and upper WLAN single/dual notch behavior independent controlling notched behavior tunable band-notch behavior overlay cognitive radio applications frequency-agile WLAN notched antennas 5G URLLC tactile internet

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Insight into fluorescence properties of 14 selected toxic single-ring aromatic compounds in water:Experimental and DFT study

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 59-74页

作者： muhammad Farooq Saleem Khan Jing Wu Cheng Cheng Mona Akbar Bo Liu Chuanyang Liu Jian Shen Yu Xin State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation(Suzhou) Tsinghua UniversitySuzhou 215000China School of Physical Science and Technology&Jiangsu Key Laboratory of Thin Films Soochow UniversitySuzhou 215006China

Various single-ring aromatic compounds in water sources are of great concern due to its hazardous impact on the environment and human *** fluorescence excitation-emission matrix(Eems)spectrophotometry is a useftil method to identify organic pollutants in *** study provides a detailed insight into the fluorescence properties of the 14 selected toxic single-ring aromatic compounds by experimental and theoretical *** theoretical analysis were done with Time-Dependent Density Functional Theory(TD-DFT)and B3LYP/6-31G(d,p)basis set,whereas,Polarizable Continuum Model(PCM)was used to consider water as *** selected compounds displayed their own specific excitation-emission(Ex/em)wavelengths region,at Exemem was observed *** at 240 nm-260 nm and em at 255 nm-300 *** as a strong aromatic base has longer em(340 nm)than alkyl,carbonyl,and halogens substituted *** lone pair of electrons at amide substituent serves as a 7r-electron contributor into the aromatic ring,hence increasing the stability and transition energy,which results in longer emission and low quantum yield for the *** fluorescence of halogenated benzenes illustrates an increase in the HOMO-LUMO energy gap and a decrease in quantum yield associated with atomic size(F>Cl>Br>I).In this study the theoretical results are in line with experimental *** understanding of fluorescence and photophysical properties are of great importance in the identification of these compounds in the water.

关键词： Fluorescence Photophysical properties Effect of the substituent Toxic aromatic compounds

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Antibacterial Action of Chemically Synthesized and Laser Generated Silver Nanoparticles against Human Pathogenic Bacteria

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Journal of Materials Science & Technology 2016年第8期32卷 721-728页

作者： Nosheen Zafar Shahzadi Shamaila Jawad Nazir Rehana Sharif muhammad Shahid Rafique Jalees Ul-Hasan Syeda Ammara Hina Khalid Department of Physics University of Engineering and Technology Lahore 54890 Pakistan Department of Microbiology University of Veterinary and Animal Sciences Lahore Pakistan Department of Physics Forman Christian College A Charted University Lahore Pakistan

Silver nanoparticles in the range of 10-40 nm were synthesized chemically and by laser ablation, em- ployed for in vitro antibacterial action against human pathogenic bacterium. Their formation was evidenced by UV-visible spectrophotometer; particle size confirmed by atomic force microscopy, crystal structure determined by X-ray diffraction and chemical composition investigated by Fourier transform infrared spec- troscopy. The calculated MIC （minimum inhibitory concentration） of chemically synthesized nanoparticles with 30-40 nm in size are 2.8 μg/mL 4.37 μg/mL 13.5μg/mL and 2.81 p.g/mL for E. coil, S. aureus, B. subtillis and Salmonella, respectively. Whereas laser ablated nanoparticles exhibit MIC of 2.10 μg/mL 2.36 μg/ mL and 2.68 μg/mL for E. coli, S. aureus and Salmonella, respectively.

关键词： Chemically synthesized and laser ablated nanoparticles UV-visible spectrophotometer Gram negative and gram positive bacteria

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Mn0.8Zn0.2Fe2O4 nanoparticulates spinel ferrites:An approach to enhance the antenna field strength for improved magnitude versus offset(MVO)

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Progress in Natural Science:Materials International 2014年第4期24卷 364-372页

作者： Majid Niaz Akhtar Nadeem Nasir muhammad Kashif Noorhana Yahya Mukhtar Ahmad Ghulam Murtaza muhammad Azhar Khan M.H.Asif A.Sattar R.Raza M.Saleem S.N.Khan Department of Physics COMSATS Institute of Information Technology Electrical and Electronic Engineering Department Universiti Teknologi PETRONAS Fundamental and Applied Sciences Department National Textile University Fundamental and Applied Sciences Department Universiti Teknologi PETRONAS Centre for Advanced Studies in Physics G.C.University Department of Physics The Islamia University of Bahawalpur

Electromagnetic signals in deep reservoir are very weak so that it is difficult to predict about the presence of hydrocarbon in seabed logging(SBL) *** the present work,Mn0.8Zn0.2Fe2O4 nanoferrites were prepared by a sol–gel technique at different sintering temperatures of450 °C,650 °C and 850 °C to increase the strength of electromagnetic(em) ***,FESem,Raman spectroscopy and HRTem were used to analyze the phase,surface morphology and size of the *** properties of the nanoferrites were also measured using an impedance network ***,nanoferrites sintered at 850 °C with initial permeability of 200 and Q factor of 50 were used as magnetic feeders with the em *** scale experiments were performed to investigate the effect of magnetic field strength in scale *** and MATLAB softwares were also used to confirm the oil presence in scale *** was observed that the magnitude of the em waves for the antenna was increased up to 233%.Finally,the correlation values also show 208% increase in the magnetic field strength with the presence of the ***,antenna with Mn0.8Zn0.2Fe2O4 nanoferrites based magnetic feeders can be used for deep water and deep target hydrocarbon exploration.

关键词： Nanoferrites Transmission Electron Microscopy Initial permeability Q factor Antenna

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Qualitatively and quantitatively assessing the aggregation ability of sludge during aerobic granulation process combined XDLVO theory with physicochemical properties

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Journal of Environmental Sciences 2018年第5期30卷 154-160页

作者： Shasha Yuan Mingming Gao Hui Ma muhammad Zaheer Afzal Yun-Kun Wang Mingyu Wang Hai Xu Shu-Guang Wang Xin-Hua Wang Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityJinan 250100China Beijing Municipal Commission of Urban Planning Tongzhou District Branch Beijing 101101China State Key Laboratory of Microbial Technology School of Life SciencesShandong UniversityJinan 250100China

Inexact mechanism of aerobic granulation still impedes optimization and application of aerobic granules. In this study, the extended Derjaguin, Landau, Verwey, and Overbeek（XDLVO） theory and physicochemical properties were combined to assess the aggregation ability of sludge during aerobic granulation process qualitatively and quantitatively. Results show that relative hydrophobicity of sludge and polysaccharide content of extracellular polymeric substances（EPS） increased, while electronegativity of sludge decreased during acclimation phase. After 20 days＇ acclimation, small granules began to form due to high aggregation ability of sludge. Since then, coexisted flocs and granules possessed distinct physicochemical properties during granulation and maturation phase. The relative hydrophobicity decreased while electronegativity increased for flocs, whereas that for granules presented reverse trend. Through analyzing the interaction energy using the XDLVO theory, small granules tended to self-grow rather than self-aggregate or attach of flocs due to poor aggregation ability between flocs and granules during the granulation phase. Besides, remaining flocs were unlikely to self-aggregate owing to poor aggregation ability, low hydrophobicity and high electronegativity.

关键词： Aerobic granulation XDLVO theory Aggregation ability Extracellular polymeric substances

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Assessment of Rock Mass Quality and Deformation Modulus by empirical Methods along Kandiah River, KPK, Pakistan

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Open Journal of Geology 2018年第10期8卷 947-964页

作者： Mian Sohail Akram Kamran Mirza muhammad Zeeshan muhammad Asad Jabbar Institute of Geology University of the Punjab Lahore Pakistan

The pivotal aim of this study is to evaluate the rock mass characterization and deformation modulus. It is vital for rock mass classification to investigate important parameters of discontinuities. Therefore, Rock Mass Rating (RMR) and Tunneling quality index (Q) classification systems are applied to analyze 22 segments along proposed tunnel routes for hydropower in Kandiah valley, Khyber Pakhtunkhwa, Pakistan. RMR revealed the range of fair to good quality rocks, whereas Q yielded poor to fair quality rocks for investigated segments of the rock mass. Besides, em values were acquired by empirical equations and computer-aided program RocLab, and both methods presented almost similar variation trend of their results. Hence, the correlations of em with Q and RMR were carried out with higher values of the regression coefficient. This study has scientific significance to initially understand the rock mass conditions of Kandiah valley.

关键词： Rock Mass Classification RMR and Q Deformation Modulus (em) empirical Equations RocLab Tunnel

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A Multifunctional Chiral Metasurface with Asymmetric Transmission and Linear-Polarization Conversion

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第S1期41卷 21-26页

作者： AFZAL Ahmed CAO Qunsheng muhammad Sajjad College of Electronics and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China

In this paper,a multifunctional chiral metasurface is presented to achieve asymmetric transmission(AT)and linear-polarization conversion(LPC).The designed metasurface consists of a cross swords-like shape and two holes in the lower side of the unit *** the frequency band from 8.3 GHz to 10.4 GHz,AT is realized with more than 90%efficiency and the same chiral metasurface transforms linear polarized wave into its orthogonal counterpart with high *** LPC,the polarization conversion ratio(PCR)is greater than 95%.The proposed metasurface is stable against the incident angles of striking electromagnetic(em)waves up to 60°for both operations of AT and LPC.

关键词： chiral metasurface polarization conversion asymmetric tranmission plasmon resonances

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Modeling of Antenna for Deep Target Hydrocarbon Exploration

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Journal of Electromagnetic Analysis and Applications 2012年第1期4卷 30-41页

作者： Noorhana Yahya Nadeem Nasir Majid Niaz Akhtar muhammad Kashif Hasnah Mohd Zaid Afza Shafie 不详

Nowadays control source electromagnetic method is used for offshore hydrocarbon exploration. Hydrocarbon detection in sea bed logging (SBL) is a very challenging task for deep target hydrocarbon reservoir. Response of electromagnetic (em) field from marine environment is very low and it is very difficult to predict deep target reservoir below 2 km from the sea floor. This work premise deals with modeling of new antenna for deep water deep target hydrocarbon exploration. Conventional and new em antennas at 0.125 Hz frequency are used in modeling for the detection of deep target hydrocarbon reservoir. The proposed area of the seabed model (40 km ′ 40 km) was simulated by using CST (computer simulation technology) em studio based on Finite Integration Method (FIM). Electromagnetic field components were compared at 500 m target depth and it was concluded that Ex and Hz components shows better resistivity contrast. Comparison of conventional and new antenna for different target depths was done in our proposed model. From the results, it was observed that conventional antenna at 0.125 Hz shows 70%, 86% resistivity contrast at target depth of 1000 m where as new antenna showed 329%, 355% resistivity contrast at the same target depth for Ex and Hz field respectively. It was also investigated that at frequency of 0.125 Hz, new antenna gave 46% better delineation of hydrocarbon at 4000 m target depth. This is due to focusing of electromagnetic waves by using new antenna. New antenna design gave 125% more extra depth than straight antenna for deep target hydrocarbon detection. Numerical modeling for straight and new antenna was also done to know general equation for electromagnetic field behavior with target depth. From this numerical model it was speculated that this new antenna can detect up to 4.5 km target depth. This new em antenna may open new frontiers for oil and gas industry for the detection of deep target hydrocarbon reservoir (HC).

关键词： Electromagnetic Hydrocarbon SBL Antenna CST

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