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An asymmetrical multilevel inverter with minimum voltage stress and fewer components for photovoltaic renewable-energy system

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Clean Energy 2024年第1期8卷 1-22页

作者： Rabail Memon mukhtiar Ahmed Mahar Abdul Sattar Larik Syed Asif Ali shah Department of Electrical Engineering Mehran University of Engineering and TechnologyJamshoroPakistan

The enhanced power quality provided by multilevel inverters(MLIs)has made them more appropriate for medium-and high-power applications,including photovoltaic ***,a prevalent limitation involves the necessity for numerous switches and increased voltage stress across these switches,consequently increasing the overall system *** address these challenges,a new 17-level asymmetrical MLI with fewer components and low voltage stress is proposed for the photovoltaic *** innovative MLI configuration has four direct current(DC)sources and 10 *** on the trinary sequence,the proposed topology uses photovoltaics with boost converters and fuzzy logic controllers as its DC *** equations are used to calculate cru-cial parameters for this proposed design,including total standing voltage per unit(TSVPU),cost function per level(CF/L),component count per level(CC/L)and voltage stress across the *** comparison is conducted by considering switches,DC sources,TSVPU,CF/L,gate driver circuits and CC/L with other existing MLI *** analysis is carried out under various conditions,encompassing different levels of irradiance,variable loads and modulation *** reduce the total harmonic distortion of the suggested topology,the phase opposition disposition approach has been *** suggested framework is simulated in MATLAB®/Simulink®.The results indicate that the proposed topology achieves a well-distributed stress profile across the switches and has CC/L of 1.2.,TSVPU of 5 and CF/L of 4.58 and 5.76 with weight coefficients of 0.5 and 1.5,*** values are not-ably superior to those of existing MLI *** results demonstrate that the proposed topology maintains a consistent output at varying irradiance levels with FLCs and exhibits robust performance under variable loads and diverse modulation ***,the total harmonic distortion achieved with phase opposition disposi

关键词： asymmetrical multilevel inverter photovoltaic system renewable energy component count per level cost function per level total standing voltage per unit phase opposition disposition technique

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Co-occurrence of per- and polyfluoroalkyl substances, heavy metals and polycyclic aromatic hydrocarbons and their composite impacts on microbial consortium in soil: A field study

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Pedosphere 2024年第4期34卷 736-748页

作者： Meng ZHANG Qing WANG Xin SONG mukhtiar ALI Zhiwen TANG Xin LIU Zhuanxia ZHANG Shurong MA Jinhui BI Zhongyuan LI Key Laboratory of Saline-Alkali Vegetation Ecology Restoration Northeast Forestry UniversityHarbin 150040China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China Center International Group Co. Ltd.Beijing 101160China China Construction Eighth Engineering Division Corp. Ltd.Shanghai 200122China

This is the first study to report the co-occurrence of per-and polyfluoroalkyl substances(PFASs),heavy metals,and polycyclic aromatic hydrocarbons(PAHs)and their impacts on the native microbial consortium in soil due to the long-term *** PFASs,heavy metals,and PAHs were detected in soil samples collected at 2.6 m below the ground surface at different sampling locations in a steel-making *** total concentrations of PFASs varied from 6.55 to 19.79 ng g^(-1),with perfluorooctane sulfonate(PFOS),perfluorobutane sulfonate,and 6:2.chlorinated polyfluorinated ether sulfonate(alternative of PFOS)being the predominant *** concentrations of arsenic,cadmium,and lead were detected in the ranges of 4.40–12.0.00,0.01–8.67,and 18.00–647.00 mg kg^(-1),respectively,and the concentration of total PAHs was detected in the range of 1.02.131.60 mg kg^(-1).The long-term exposure to mixed contaminants of PFASs,heavy metals,and PAHs led to lower richness and diversity of microbial communities in *** soil bacterial communities were mainly composed of Pseudomonas,norank_p_GAL15,Leptothrix,norank_o_Rokubacteriales,and *** between soil environmental factors and microbial communities indicated that cation exchange capacity and total phosphorus were two key factors in shaping the composition of native microbial ***,Arthrobacter,Leptothrix,and Sphingobium were found to be significantly positively correlated with PFAS concentrations,indicating that these genera could tolerate the stress exerted by PFASs,along with the stress imposed due to the presence of heavy metals or/and PAHs.

关键词： arsenic cation exchange capacity mixed contaminant native microbial community perfuorooctane sulfonate total phosphorus

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Advancements in prokaryotic systematics and the role of Bergey's International Society for Microbial Systematics in addressing challenges in the meta-data era

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National Science Review 2024年第07期11卷 292-304页

作者： Jian-Yu Jiao Rashidin Abdugheni Dao-Feng Zhang Iftikhar Ahmed mukhtiar Ali Maria Chuvochina Svetlana N.Dedysh Xiuzhu Dong Markus G?ker Brian P.Hedlund Philip Hugenholtz Kamlesh Jangid Shuang-Jiang Liu Edward R.B.Moore Manik Prabhu Narsing Rao Aharon Oren Ramon Rossello-Mora Bhagwan Narayan Rekadwad Nimaichand Salam Wensheng Shu Iain C.Sutcliffe Wee Fei Aaron Teo Martha E.Trujillo Stephanus N.Venter William B.Whitman Guoping Zhao Wen-Jun Li State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) School of Life Sciences Sun Yat-Sen University State Key Laboratory of Desert and Oasis Ecology Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsXinjiang Institute of Ecology and Geography Chinese Academy of Sciences Jiangsu Province Engineering Research Center for Marine Bio-resources Sustainable Utilization&College of Oceanography Hohai University National Culture Collection of Pakistan(NCCP) Land Resources Research Institute(LRRI) National Agricultural Research Centre(NARC) The University of Queensland School of Chemistry and Molecular Biosciences Australian Centre for Ecogenomics Winogradsky Institute of Microbiology Research Center of BiotechnologyRussian Academy of Sciences State Key Laboratory of Microbial Resources Institute of Microbiology Chinese Academy of Sciences Leibniz Institute DSMZ–German Collection of Microorganisms and Cell Cultures School of Life Sciences University of Nevada Nevada Institute of Personalized Medicine University of Nevada Bioenergy Group MACS Collection of Microorganisms Agharkar Research Institute State Key Laboratory of Microbial Technology Shandong University Department of Infectious Disease Institute for Biomedicine and Culture Collection University of Gothenburg(CCUG) Institute for BiomedicineSahlgrenska AcademyUniversity of Gothenburg Instituto de Ciencias Aplicadas Facultad de Ingeniería Universidad Autónoma de Chile The Alexander Silberman Institute of Life Sciences The Edmond J.Safra Campus The Hebrew University of Jerusalem Marine Microbiology Group Department of Animal and Microbial Biodiversity Mediterranean Institute for Advanced Studies(IMEDEA CSIC-UIB) MicrobeAI Lab Division of Microbiology and Biotechnology Yenepoya Research Centre Yenepoya(Deemed to be University) National Agri-Food Biotechnology Institute Institute of Ecological Science Sch

Prokaryotes are ubiquitous in the biosphere, important for human health and drive diverse biological and environmental processes. Systematics of prokaryotes, whose origins can be traced to the discovery of microorganisms in the 17th century, has transitioned from a phenotype-based classification to a more comprehensive polyphasic taxonomy and eventually to the current genome-based taxonomic *** transition aligns with a foundational shift from studies focused on phenotypic traits that have limited comparative value to those using genome sequences. In this context, Bergey's Manual of Systematics of Archaea and Bacteria(BMSAB) and Bergey's International Society for Microbial Systematics(BISMiS) play a pivotal role in guiding prokaryotic systematics. This review focuses on the historical development of prokaryotic systematics with a focus on the roles of BMSAB and BISMiS. We also explore significant contributions and achievements by microbiologists, highlight the latest progress in the field and anticipate challenges and opportunities within prokaryotic systematics. Additionally, we outline five focal points of BISMiS that are aimed at addressing these challenges. In conclusion, our collaborative effort seeks to enhance ongoing advancements in prokaryotic systematics, ensuring its continued relevance and innovative characters in the contemporary landscape of genomics and bioinformatics.

关键词： prokaryotic systematics Bergey's Manual of Systematics of Archaea and Bacteria (BMSAB) Bergey's International Society for Microbial Systematics (BISMiS) meta-data era

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Improved Efficiency Test Method for the Motor Controller with SiC MOSFETs

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Journal of Beijing Institute of Technology 2020年第3期29卷 294-302页

作者： Wei Wang Qiang Song Yiting Li mukhtiar Ahmad School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Collaborative Innovation Center for Electric Vehicles Beijing 100081China

The traditional measurement method was inaccurate to evaluate the motor controller efficiency,which the measurement efficiency value could be more than 100%in practical testing *** deal with this issue,an improved electrical measurement method for the motor controller efficiency is proposed in this paper,which is established by analyzing the power loss distribution and phase currents of the motor *** is demonstrated that the SiC MOSFET chips are the main power loss devices in the motor controller,accounting for more than 93.1%of the total power *** accuracy of the proposed method is compared with the traditional method in *** shows that the test error of the efficiency obtained by the traditional method fluctuates on a large scale,which varied from 0.094%to 1.911%.Compared with the traditional method,the test error of the proposed method appears to be less than 0.083%,which provides significant guidance for the motor controller efficiency test and design.

关键词： electrical measurement method motor controller efficiency power loss distribution SiC MOSFET

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Inducing opto-electronic and spintronic trends in bilayer h-BN through TMO3 clusters incorporation: Ab-initio study

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Chinese Physics B 2019年第11期28卷 284-294页

作者： Irfan Ahmed Muhammad Rafique mukhtiar Ahmed Mahar Abdul Sattar Larik Mohsin Ali Tunio Yong Shuai Mehran University of Engineering and Technology SZABCampusKhairpur Mirs’Pakistan School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Mehran University of Engineering and Technology JamshoroSindhPakistan

The band structure, magnetism, charge distribution, and optics parameters of TMO3–h-BN hybrid systems are investigated by adopting first-principles study(FPS) calculations. It is observed that the TMO3 clusters add finite magnetic moments to bilayer h-BN(BL/h-BN), thereby making it a magnetic two-dimensional(2.) material. Spin-polarized band structures for various TMO3–BL/h-BN hybrid models are calculated. After the incorporation of TMO3, BL/h-BN is converted into semimetal or conducting material in spin up/down bands, depending on the type of impurity cluster present in BL/h-BN lattice. Optics parameters are also investigated for the TMO3–BL/h-BN complex systems. The incorporation of TMO3 clusters modifies the absorption and extinction coefficient in visible range, while static reflectivity and refraction parameter increase. It can be surmised that the TMO3 substitution in BL/h-BN is a suitable technique to modify its physical parameters thus making it functional for nano/opto-electronic applications, and an experimental approach can be adapted to reinforce the outcomes of this study.

关键词： bilayer h-BN band structure density of states magnetic moments optics

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Performance Evaluation of Energy Meters Under Nonlinear Loads

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Journal of Shanghai Jiaotong university(Science) 2017年第2期22卷 133-138页

作者： GUL Mehr 邰能灵 MAHAR mukhtiar Ahmed 黄文焘 LARIK Abdul Sattar Department of Electrical Engineering Shanghai Jiao Tong University Department of Electrical Engineering Balochistan University of Information Technology Engineering and Management Sciences (BUITEMS) Department of Electrical Engineering Mehran University of Engineering & Technology

Due to rapid advancements in power electronics, the utilization of electronically switched loads and nonlinear loads is increasing gradually in the electrical power system. These loads create problems of measuring instruments, when connected to the power distribution systems. In this paper, an experimental investigation has been carried out to analyze the performance of single-phase watt-hour (induction and electronic types) energy meters that are being used in Pakistan. The accuracy of the energy meters has been tested under different household nonlinear loads, at various power factors and also at different supply voltage levels. Power factor and total harmonic distortion (THD) of different household loads are also recorded in the experimental work. A hardware based experimental setup has been designed to perform the experimental work. The experimental results have been compared to Water and Power Development Authority (WAPDA) standards for energy meters. © 2.17, Shanghai Jiaotong University and Springer-Verlag Berlin Heidelberg.

关键词： energy meter accuracy nonlinear loads experimental investigation harmonic distortion power factor

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Reservoir Quality Assessment of the Upper Permian Chhidru Formation, Salt and Surghar Ranges, Pakistan

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Acta Geologica Sinica(English Edition) 2021年第6期95卷 2120-2137页

作者： Muhammad ZAHIR Muhammad AWAIS mukhtiar GHANI Mohibullah MOHIBULLAH Osman SALAD HERSI Irfan U.JAN Sajjad AHMAD Hamid IQBAL Centre of Excellence in Mineralogy University of BalochistanQuetta 87300Pakistan Department of Geology University of SwabiAnbarKhyber Pakhtunkhwa 23561Pakistan Geological Survey of Pakistan HQQuetta 87300Pakistan Department of Geology University of BalochistanQuetta 87300Pakistan University of Regina Geology 3737 Wascana Parkway ReginaSaskatchewan S4S0A2Canada National Centre of Excellence in Geology University of PeshawarPeshawar 25000Pakistan Department of Geology University of PeshawarPeshawar 25000Pakistan Oil and Gas Development Company Islamabad 44800Pakistan

The Late Permian succession of the Upper Indus Basin in northeastern Pakistan is represented by the carbonatedominated Zaluch Group, which consists of the Amb, Wargal and Chhidru formations, which accumulated on the southwestern shelf of the Paleo-Tethys Ocean, north of the hydrocarbon-producing Permian strata of the Arabian Peninsula. The reservoir properties of the mixed clastic-carbonate Chhidru Formation(CFm) are evaluated based on petrography, using scanning electron microscopy(SEM), energy dispersive x-ray spectroscopy(EDX) and x-ray diffraction(XRD) techniques. The diagenetic features are recognized, ranging from marine(isopachous fibrous calcite, micrite), through meteoric(blocky calcite-I, neomorphism and dissolution) to burial(poikilotopic cement, blocky calcite-II-III, fractures, fracture-filling, and stylolites). Major porosity types include fracture and moldic, while inter-and intra-particle porosities also exist. Observed visual porosity ranges from 1.5%–7.14% with an average of 5.15%. The sandstone facies(CMF-4) has the highest average porosity of 10.7%, whereas the siliciclastic grainstone microfacies(CMF-3) shows an average porosity of 5.3%. The siliciclastic mudstone microfacies(CMF-1) and siliciclastic wacke-packestone microfacies(CMF-2. show the lowest porosities of 4.8% and 5.0%, respectively. Diagenetic processes like cementation, neomorphism, stylolitization and compaction have reduced the primary porosities;however, processes of dissolution and fracturing have produced secondary porosity. On average, the CFm in the Nammal Gorge, Salt Range shows promise and at Gula Khel Gorge, Trans-Indus, the lowest porosity.

关键词： sedimentary petrography diagenesis hydrocarbon reservoir Changhsingian Chhidru Formation Salt Range Surghar Range Pakistan

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MDEV Model:A Novel Ensemble-Based Transfer Learning Approach for Pneumonia Classification Using CXR Images

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Computer Systems Science & Engineering 2023年第7期46卷 287-302页

作者： Mehwish Shaikh Isma Farah Siddiqui Qasim Arain Jahwan Koo mukhtiar Ali Unar Nawab Muhammad Faseeh Qureshi Department of Software Engineering Mehran University of Engineering and TechnologyJamshoroPakistan College of Software Sungkyunkwan UniversitySuwonKorea Department of Computer Systems Mehran University of Engineering and TechnologyJamshoroPakistan Department of Computer Education Sungkyunkwan UniversitySeoulKorea

Pneumonia is a dangerous respiratory disease due to which breathing becomes incredibly difficult and painful;thus,catching it early is *** physicians’time is limited in outdoor situations due to many patients;therefore,automated systems can be a *** input images from the X-ray equipment are also highly unpredictable due to variances in radiologists’***,radiologists require an automated system that can swiftly and accurately detect pneumonic lungs from chest *** medical classifications,deep convolution neural networks are commonly *** research aims to use deep pretrained transfer learning models to accurately categorize CXR images into binary classes,i.e.,Normal and *** MDEV is a proposed novel ensemble approach that concatenates four heterogeneous transfer learning models:Mobile-Net,DenseNet-2.1,EfficientNet-B0,and VGG-16,which have been finetuned and trained on 5,856 CXR *** evaluation matrices used in this research to contrast different deep transfer learning architectures include precision,accuracy,recall,AUC-roc,and *** model effectively decreases training loss while increasing *** findings conclude that the proposed MDEV model outperformed cutting-edge deep transfer learning models and obtains an overall precision of 92.2.%,an accuracy of 92.15%,a recall of 90.90%,an auc-roc score of 90.9%,and f-score of 91.49%with minimal data pre-processing,data augmentation,finetuning and hyperparameter adjustment in classifying Normal and Pneumonia chests.

关键词： Deep transfer learning convolution neural network image processing computer vision ensemble learning pneumonia classification MDEV model

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Power Factor Improvement of AC-DC Converter Based on Separately Excited DC Motor Using Passive Filter

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Open Journal of Energy Efficiency 2016年第3期5卷 71-77页

作者： Shazia Baloch mukhtiar Ahmed Mahar Raza Haider Shakeel Ahmed Electrical Engineering Department Balochistan University of Engineering and Technology Khuzdar Pakistan Electrical Engineering Department Mehran University of Engineering and Technology Jamshoror Pakistan Civil Engineering Department Balochistan University of Engineering and Technology Khuzdar Pakistan

In industries DC motor drives are very essential due to their high performance applications such as its reliability, ease of control, low cost and simplicity. And speed control of these motors is very easy due to power electronic AC-DC converters. These power electronic converters are with prominent low power factor and higher Total Harmonic Distortion (THD). These converters operate only for short time resulting non-sinusoidal waveform. This problem of harmonic distortion can be mitigated by reshaping the non-sinusoidal waveform to pure sine wave. Different wave shaping techniques have been developed by using different filters among which one is tuned passive filter. This paper proposed power factor improvement and harmonic mitigation of AC-DC converters based on separately excited DC motor using tuned passive filter. In this context experimental model is designed and results are analyzed by power quality analyzer.

关键词： DC Motors AC-DC Converters Power Factor Total Harmonic Distortion Passive Filters

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Ag/GeSe纳米薄膜非线性光学性质研究

Ag/GeSe纳米薄膜非线性光学性质研究

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作者：阿穆（mukhtiar Ali）哈尔滨师范大学

学位级别：硕士

A broad variety of optical limiting devices,optical switches,optical memory,and other devices designed based on non-linear optical phenomena have enhanced people's lives in the modern era of digital information,and optoelectronic applications were becoming a fundamental component of daily ***,it is crucial to carry out research and produce improved non-linear optical materials.A typical IV-VI semiconductor with exceptional photoelectric properties,germanium selenide(Ge Se)exhibits a suitable band gap and a very high visible-near-infrared absorption *** research has shown that a composite structure may significantly alter a semiconductor material,improve its performance,and expand its range of *** Se photoelectric performance may be improved,and its application space can be increased,by modifying the composite with the appropriate polymers or precious metal *** this study,Ge Se and Ag/Ge Se thin films were successfully *** acquired samples' morphology,structure,and linear and non-linear optical properties were examined using related technologies,obtaining significant conclusions.(1)Ag/Ge Se thin films were prepared by magnetron *** results of Xray diffractometer(XRD)research indicate that the films are maintained in amorphous *** scanning electron microscope(SEM)results show that with the increase of direct current(DC)sputtering power,the increase of Ag doping leads to clustering.(2.The linear absorption characteristics of the samples were measured by an ultraviolet-visible spectrophotometer(UV-VIS)and the band gap was calculated by *** linear absorption peaks of Ag/Ge Se thin films were red-shifted and the band gap decreased.(3)The non-linear properties of pure and Ag/Ge Se thin films,which were obtained by fs Z-scan experiment at 800 nm,were used to understand the mechanism of the nonlinear response and *** results manifested that Ag/Ge Se thin films overall show saturated a

关键词： Germanium Selenide(GeSe) thin films non-linear optical properties Z-scan Magnetron sputtering

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