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Intelligent Islanding Detection of Multi-distributed Generation Using Artificial Neural Network Based on Intrinsic Mode Function Feature

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 511-520页

作者： Samuel Admasie syed Basit Ali Bukhari Teke Gush Raza haider Chul Hwan Kim Department of Electrical and Computer Engineering Sungkyunkwan UniversitySuwonSouth Korea U.S.-Pakistan Center for Advanced Studies in Energy(USPCAS-E) National University of Sciences and Technology(NUST)H-12 IslamabadPakistan Department of Electrical Engineering Balochistan University of Engineering and TechnologyKhuzdar 89100Pakistan

The integration of distributed energy resources(DERs) into distribution networks is becoming increasingly important, as it supports the continued adoption of renewable power generation, combined heat and power plants, and storage systems. Nevertheless, inadvertent islanding operation is one of the major protection issues in distribution networks connected to DERs. This study proposes an intelligent islanding detection method(IIDM) using an intrinsic mode function(IMF)feature-based grey wolf optimized artificial neural network(GWO-ANN). In the proposed IIDM, the modal voltage signal is pre-processed by variational mode decomposition followed by Hilbert transform on each IMF to derive highly involved features. Then, the energy and standard deviation of IMFs are employed to train/test the GWO-ANN model for identifying the islanding operations from other non-islanding events. To evaluate the performance of the proposed IIDM, various islanding and non-islanding conditions such as faults, voltage sag, linear and nonlinear load and switching, are considered as the training and testing datasets. Moreover, the proposed IIDM is evaluated under noise conditions for the measured voltage signal. The simulation results demonstrate that the proposed IIDM is capable of differentiating between islanding and non-islanding events without any sensitivity under noise conditions in the test signal.

关键词： Distributed energy resource(DER) intrinsic mode function(IMF) grey wolf optimized artificial neural network(GWO-ANN) intelligent islanding detection method(IIDM) microgrid

Corrosion resistance and thermal stability of sputtered Fe44Al34Ti7N15 and Al61Ti11N28 thin films for prospective application in oil and gas industry

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Progress in Natural Science:Materials International 2021年第5期31卷 688-697页

作者： Mahbub Alam Maruf syed Muhammad Mujtaba Rizvi Mohammed Noor-A-Alam Donghyun Shin Waseem haider Ishraq Shabib School of Engineering and Technology Central Michigan University Mechanical Engineering Indiana University-Purdue University Columbus

Fe-and Al-based thin-film metallic glass coatings(Fe44Al34Ti7N15and Al61Ti11N28) were fabricated using magnetron co-sputtering technique, and their corrosion performances compared against wrought 316 L stainless steel. The results of GI-XRD and XPS analyses demonstrated amorphous structure and oxide layer formation on the surface of the fabricated thin films, respectively. The potentiodynamic(PD) polarization test in chloridethiosulfate(NH4Cl + Na2S2O3) solution revealed lower corrosion current(Icorr)(0.42 ± 0.02 μA/cm~2 and0.086 ± 0.001 μA/cm~2 Vs. 0.76 ± 0.05 μA/cm~2), lower passivation current(Ipass)(1.45 ± 0.03 μA/cm~2 and1.83 ± 0.07 μA/cm~2 Vs. 1.98 ± 0.04 μA/cm~2), and approximately six-fold higher breakdown potential(Ebd) for Fe-and Al-based coatings than those of wrought 316 L stainless steel. Electrochemical Impedance Spectroscopy(EIS) of both films showed 4-and 2-fold higher charge transfer resistance(Rct), 7-and 2.5-times higher film resistance(Rf), lower film capacitance values(Qf)(10 ± 2.4 μS-sacm-2, and 5.41 ± 0.8 μS-sacm-2Vs. 18 ± 2.21 μSsacm-2), and lower double-layer capacitance values(Qdl)(31.33 ± 4.74 μS-sacm-2, and 15.3 ± 0.48 μS-sacm-2Vs.43 ± 4.23 μS-sacm-2), indicating higher corrosion resistance of the thin films. Cyclic Voltammetry(CV) scan exhibited that the passive films formed on the Fe-and Al-based coatings were more stable and less prone to pitting corrosion than the wrought 316 L stainless steel. The surface morphology of both films via SEM endorsed the CV scan results, showing better resistance to pitting corrosion. Furthermore, the thermal analysis via TGA and DSC revealed the excellent thermal stability of the thin films over a wide temperature range typically observed in oilgas industries.

关键词： Thin films Metallic glasses X-ray diffraction Photoelectron spectroscopy Corrosion Thermal analysis

A 2.4 GHz Digital Power Amplifier with a 20 MHz Channel Bandwidth Based on 65nm CMOS Process

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A 2.4 GHz Digital Power Amplifier with a 20 MHz Channel Band...

作者： syed Irfan haider（瑞凡）东南大学

学位级别：硕士

功率放大器(PA)是所有射频发射器中的关键结构模块。为了降低成本并实现无线电系统级芯片(So C),需要将整个收发器和PA集成在单个CMOS芯片中。虽然数字电路从微缩技术中获得了优势,传统PA结构在较低电源电压下对面临着线性度、输出功率... 详细信息

功率放大器(PA)是所有射频发射器中的关键结构模块。为了降低成本并实现无线电系统级芯片(So C),需要将整个收发器和PA集成在单个CMOS芯片中。虽然数字电路从微缩技术中获得了优势,传统PA结构在较低电源电压下对面临着线性度、输出功率、传输容(带宽)和效率求等挑战。数字功率放大器(DPA)具有高效率和高线性度优势,设计CMOS数字功率放大器具有重要意义和应用价值。本论文基于65nm CMOS工艺,设计了一种的20MHz通道带宽的2.4GHz数字功率放大器。该PA采用数字极性极化架构来提高信号放大时的整体功率效率,以满足高线性度要求。功率放大器由64个并行射频放大器组成,这些放大器由恒定包络射频相位调制信号驱动。单元放大器由6位包络码数字驱动,以实现射频输出的非恒定包络,所有单元放大器都由6位二进制代码驱动。DPA的个并联单元均采用A类放大器结构。论文完成了电路设计、前仿真、版图设计和后仿真。后仿真结果表明,在工作频率为2.4GHz,通道带宽为20MHz。时,该数字功率放大器的S21增益为16.8891dB。EVM为-9.4 dB的(64 QAM OFDM)信号,它实现了峰值功率附加效率为29.2504%的峰值功率附加效率,同时峰值输出功率为21.4431 dbmdBm采用2.5 V电源供电,而总芯片,版图面积仅为308μm x 508μm。论文设计的数字功率放大器满足设计指标要求,在流片和测试后可以应用于发射机系统。

关键词： CMOS RF 功率放大器 OFDM IEEE802.11g 极性调制匹配网络

Thickness-dependent monochalcogenide GeSe-based CBRAM for memory and artificial electronic synapses

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Nano Research 2022年第3期15卷 2263-2277页

作者： Asif Ali haider Abbas Muhammad Hussain syed Hassan Abbas Jaffery Sajjad Hussain Changhwan Choi Jongwan Jung HMC(Hybrid Materials Center)and Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 143–747Republic of Korea Division of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea

Investigating the promising chalcogenide materials for the development of memory and advanced neuromorphic computing applications is a critical step in realizing electronic memory and synaptic devices that can efficiently emulate biological synaptic ***,the assessment of monochalcogenide materials for the fabrication of highly scalable memory and electronic synaptic devices that can accurately mimic synaptic functions remain *** the present study,we investigated the thickness-dependent resistive switching(RS)behavior of conductive bridge random access memory(CBRAM)based on a monochalcogenide GeSe switching medium for its possible application in high-performance memory and electronic *** thin films of different thicknesses(6,13,24,35,47,and 56 nm)were deposited via sputtering to fabricate CBRAM devices with a stacking sequence of Ag/GeSe/Pt/Ti/SiO_(2).The devices exhibited compliance current(CC)-free and electroforming-free RS with highly stable endurance and retention characteristics with no major *** devices with a thickness of 6 nm had a low-resistance state(LRS),which required an initial reset to ensure reliable switching *** devices with a thickness of 47 nm and above exhibited the co-existence of unipolar resistive switching(U-RS)and bipolar resistive switching(B-RS)with the CC-controlled transition between the two switching *** resistance states in the 24-nm device between a high-resistance state(HRS)and an LRS were achieved by controlling the set-CC(from 5 mA to CC-free)and the reset stop voltage(from–0.5 to–1.0 V)during the set and reset processes,*** analog RS behavior of the device was further investigated with appropriate pulse measurements to emulate vital synaptic functions,including long-term potentiation(LTP),long-term depression(LTD),spike-rate-dependent plasticity(SRDP),spike-timing-dependent plasticity(STDP),paired-pulse facilitation(PPF),paired-pulse depression(PPD)and

关键词： conductive bridge random access memory(CBRAM) resistive memory switching monochalcogenide material bipolar and unipolar resistive switching multilevel resistive switching electronic synapses

A Compact 28 GHz Millimeter Wave Antenna for Future Wireless Communication

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Computers, Materials & Continua 2022年第7期72卷 301-314页

作者： Shahid Khan Adil Bashir haider Ali Abdul Rauf Mohamed Marey Hala Mostafa Ikram syed LCOMS ASECUniversity de LorraineMetz57070France Department of Electrical and Computer Engineering Comsats University IslamabadAbbottabad Campus22060Pakistan Electrical Engineering Department Bahauddin Zakariya UniversityMultan60800Pakistan Department of Electronics Technology University of TechnologyNowshera24100Pakistan Department of Electrical Engineering National University of Sciences and TechnologyH-12Islamabad44000Pakistan Smart Systems Engineering Laboratory College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Computer Software Engineering Military College of SignalsNational University of Sciences and TechnologyIslamabad44000Pakistan

This article presents a novel modified chuck wagon dinner bell shaped millimeter wave(mm-wave)antenna at 28 *** proposed design has ultra-thin Rogers 5880 substrate with relative permittivity of *** design consists of T shaped resonating elements and two open ended side *** desired 28 GHz frequency response is achieved by careful parametric modeling of the proposed *** maximum achieved single element gain at the desired resonance frequency is 3.45 *** efficiency of the proposed design over the operating band is more than 88%.The impedance bandwidth achieved for−10 dB reference value is nearly 2.9 *** proposed antenna is transformed into four element linear array which increases the gain up to 10.5 *** fabricated prototype is tested for the measured *** is observed that measured results closely match the simulated *** considering its simple structure and focused radiation patterns,the proposed design is well suited for IoT(Internet of Things),mmWave microwave sensing,5G and future RF(Radio Frequency)frontends.

关键词： RF front-ends mmWave partial ground plane 28 GHz IoT 5G antenna

Weather Yield Model for the Semi Tropical Region (Pakistan)

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Advances in Atmospheric Sciences 1992年第3期9卷 367-372页

作者： syed Faizan haider K.H.Asif Amjad Hussain Gilani The Department of Agricultural Meteorology Uni. of Agricuture Faisalabad PakistanThe Department of Agricultural Meteorology Uni. of Agricuture Faisalabad PakistanDegree College Rawala Kot Azad Kashmir

Weather models are essential tools for checking of the effect of the weather elements in terms of their effect on the production of the crop. This research is an attempt to see the effect of only two variables i.e., temperature and rainfall for the division Faisalabad (semitropical region of Pakistan).The model fitted is of the linear form:the values of a,b, c have been found. The expected yield has been calculated by using the aridity indices (X1 and X2 ) and the result in the form of coefficient of determination R2 has been found equal to 0.166. The significance of the regression coefficient has been tested, which shows that the contribution to the yield from aridity index at germination and that at ripening is *** wheat yields are the results of a wide variety of variables, most of which show varying degree of relationship with one another, some positive and some negative in terms of output. These variables may be technology, fertilizers, pesticides, epidemics, kinds of seeds used, market price of crop and the area under cultivation etc, which can be the source of variation in the wheat yield. Since rainfall during germination and temperature at the ripening periods are the necessary factors for the yield of wheat, for this purpose these parameters have been studied in order to their contribution.

关键词： Weather Yield Model for the Semi Tropical Region Pakistan

Thermal Conductivity of Complex Plasmas Using Novel Evan-Gillan Approach

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Communications in Theoretical Physics 2018年第6期69卷 704-710页

作者： Aamir Shahzad syed Irfan haider Muhammad Kashif Muhammad Shahzad Shifa Tariq Munir Mao-Gang He Molecular Modeling and Simulation Laboratory Department of PhysicsGovernment College University Faisalabad(GCUF)Allama Iqbal RoadFaisalabad 38040Pakistan Key Laboratory of Thermo-Fluid Science and Engineering Ministry of Education(MOE)Xi'an Jiaotong UniversityXi'an 710049China

The thermal conductivity of complex fluid materials （dusty plasmas） has been explored through novel Evan-Gillan homogeneous non-equilibrium molecular dynamic （HNEMD） algorithm. The thermal conductivity coefficient obtained from HNEMD is dependent on various plasma parameters （T,k）. The proposed algorithm gives accurate results with fast convergence and small size effect over a wide range of plasma parameters. The cross microscopic heat energy current is discussed in association with variation of temperature （1/Г） and external perturbations （Pz）. The thermal conductivity obtained from HNEMD simulations is found to be very good agreement and more reliable than previously known numerical techniques of equilibrium molecular dynarnic, nonequilibrium molecular dynamic simulations. Our new investigations point to an effective conclusion that the thermal conductivity of complex dusty plasmas is dependent on an extensive range of plasma coupling （P） and screening parameter （k） and it varies by the alteration in these parameters. It is also shown that a different approach is used for computations of thermal conductivity in 2D complex plasmas and can be appropriate method for behaviors of complex systems.

关键词： complex dusty plasma homogenous nonequilibrium molecular dynamics canonical ensemble scaling law thermal conductivity Yukawa liquids

Inexpensive synthesis of a high-performance Fe3O4-SiO2-TiO2 photocatalyst： Magnetic recovery and reuse

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Frontiers of Chemical Science and Engineering 2016年第3期10卷 405-416页

作者： Nadir Abbas Godlisten N. Shao syed M. Imran Muhammad S. haider Hee Taik Kim Department of Chemical Engineering Hanyang University Ansan-si Gyeonggi-do 426-791 Republic of Korea Department of Civil and Environmental Engineering Hanyang University Ansan-si Gyeonggi-do 426-791 Republic of Korea Department of Chemical Engineering University of Gujrat HH Campus Punjab Pakistan

A sol-gel technique has been developed for the synthesis of a magnetite-silica-titania （Fe3O4-SiO2-TiO2） tertiary nanocomposite with improved photocatalytic properties based on the use of inexpensive titania and silica precursors. The exceptional photocatalytic activity of the resulting materials was demonstrated by using them to photocatalyze the degradation of methylene blue solution. The best formulation achieved 98% methylene blue degradation. An interesting feature of the present work was the ability to magnetically separate and reuse the catalyst. The efficiency of the catalyst remained high during two reuses. The synthesized nanomaterials were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron micro- scopy （TEM）, Fourier transform infrared （FTIR） spectro- scopy, ultra-violet-visible spectroscopy, diffuse reflectance spectroscopy, and thermogravimetric analysis. XRD ana- lysis revealed the formation of multicrystalline systems of cubic magnetite and anatase titania crystals. SEM and TEM characterization revealed well-developed and homo- geneously dispersed particles of size less than 15 nm. FTIR spectra confirmed the chemical interaction of titania and silica. It was further noticed that the optical properties of the prepared materials were dependent on the relative contents of their constituent metal oxides.

关键词： sol-gel photocatalysis magnetic recovery,TiO2 Fe3O4 SiO2

Hereditary hemochromatosis:Temporal trends,sociodemographic characteristics,and independent risk factor of hepatocellular cancer–nationwide population-based study

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World Journal of Hepatology 2022年第9期14卷 1804-1816页

作者： Maryam Bilal haider Ali Al Sbihi Ahmed Jamal Chaudhary syed M haider Ahmed Iqbal Edhi Department of Internal Medicine Detroit Medical CenterWayne State UniversitySinai Grace HospitalDetroitMI 48235United States System Science Binghamton UniversityBinghamtonNY 13902United States Department of Gastroenterology William Beaumont HospitalRoyal OakMI 48073United States

BACKGROUND Hereditary hemochromatosis(HH)has an increased risk of hepatocellular cancer(HCC)both due to genetic risks and iron overload as iron overload can be carcinogenic;HH impacts the increasing risk of HCC,not only through the development of cirrhosis but concerning hepatic iron deposition,which has been studied further *** To evaluate HH yearly trends,patient demographics,symptoms,comorbidities,and hospital *** secondary aim sheds light on the risk of iron overload for developing HCC in HH patients,independent of liver cirrhosis *** study investigated HH(without cirrhosis)as an independent risk factor for *** We analyzed data from National Inpatient Sample(NIS)Database,the largest national inpatient data collection in the United States,and selected HH and HCC *** was first defined in 2011 International Classification of Disease-9th edition(ICD-9)as a separate diagnosis;the HH cohort is extracted from January 2011 to December 2019 using 275.01(ICD-9)and E83.110(ICD-10)diagnosis codes of *** were excluded from the HH cohort if they had a primary or secondary diagnostic code of cirrhosis(alcoholic,non-alcoholic,and biliary),viralhepatitis,alcoholic liver disease,non-alcoholic fatty liver disease(NAFLD),and non-alcoholic steatohepatitis(NASH).We removed these patients from the HH cohort to rule out bias or ICD-10 diagnostic *** HCC cohort is selected from January 2011 to December 2019 using the ICD-9 and ICD-10 codes of *** selected a non-HCC cohort with the 1:1 fixed ratio nearest neighbor(greedy)propensity score method using the patients'age,gender,and *** performed multivariate analysis for the risk factors of HCC in the HCC and non-HCC matched *** further analyzed HH without cirrhosis(removing HH patients with a diagnosis of cirrhosis)as an independent risk factor of HCC after adjusting all known risk factors of HCC in the multivariate *** During the 2011-2019 period,a total o

关键词： Hereditary hemochromatosis Hepatocellular carcinoma,cirrhosis Hepatitis Diabetes mellitus Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis Wilson disease Alpha1-antitrypsin deficiency Blood transfusion Epidemiology Demographics Big data Hospitalization