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Adaptive Gain Tuning Rule for Nonlinear Sliding-mode Speed Control of Encoderless Three-phase Permanent Magnet Assisted Synchronous Motor

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CES Transactions on Electrical Machines and Systems 2023年第3期7卷 301-310页

作者： Ghada A.Abdel Aziz Rehan ali khan IEEE Power Electronics and Energy Conversion Department Electronics Research InstituteCairo 11843Egypt Department of Electrical Engineering University of Science&TechnologyBannuPakistan.

In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous reluctance motor(PMa-Syn RM) with considering the parameter uncertainties. A nonlinear sliding surface whose parameters are altering with time is designed at first. The proposed NSMSC can minimize the settling time without any overshoot via utilizing a low damping ratio at starting along with a high damping ratio as the output approaches the target set-point. In addition, it eliminates the problem of the singularity with the upper bound of an uncertain term that is hard to be measured practically as well as ensures a rapid convergence in finite time, through employing a simple adaptation law. Moreover, for enhancing the system efficiency throughout the constant torque region, the control system utilizes the maximum torque per ampere technique. The nonlinear sliding surface stability is assured via employing Lyapunov stability theory. Furthermore, a simple sliding mode estimator is employed for estimating the system uncertainties. The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed speed estimation and the NSMSC approach for a 1.1-k W PMa-Syn RM under different speed references, electrical and mechanical parameters disparities, and load disturbance conditions.

关键词： Permanent magnet assisted synchronous reluctance motor Nonlinear sliding mode speed control Speed estimation Parameter uncertainties Sliding mode estimator

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Health risks associated with heavy metals in the drinking water of Swat,northern Pakistan

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Journal of Environmental Sciences 2013年第10期25卷 2003-2013页

作者： Kifayatullah khan Yonglong Lu Hizbullah khan Shahida Zakir Ihsanullah Sardar khan Akbar ali khan Luo Wei Tieyu Wang Department of Environmental Sciences University of Peshawar State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-environmental Sciences Chinese Academy of Sciences Nuclear Institute for Food and Agriculture

The concentrations of heavy metals such as Cd, Cr, Cu, Mn, Ni, Pb and Zn were investigated in drinking water sources （surface and groundwater） collected from Swat valley, Khyber Pakhtunkhwa, Pakistan. The potential health risks of heavy metals to the local population and their possible source apportionment were also studied. Heavy metal concentrations were analysed using atomic absorption spectrometer and compared with permissible limits set by Pakistan Environmental Protection Agency and World Health Organization. The concentrations of Cd, Cr, Ni and Pb were higher than their respective permissible limits, while Cu, Mn and Zn concentrations were observed within their respective limits. Health risk indicators such as chronic daily intake （CDI） and health risk index （HRI） were calculated for adults and children separately. CDIs and HRIs of heavy metals were found in the order of Cr 〉 Mn 〉 Ni 〉 Zn 〉 Cd 〉 Cu 〉 Pb and Cd 〉 Ni 〉 Mn 〉 Cr 〉 Cu 〉 Pb 〉 Zn, respectively. HRIs of selected heavy metals in the drinking water were less than 1, indicating no health risk to the local people. Multivariate and univariate statistical analyses showed that geologic and anthropogenic activities were the possible sources of water contamination with heavy metals in the study area.

关键词： daily intake drinking water health risk heavy metals multivariate analysis

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Advancing PCB Quality Control:Harnessing YOLOv8 Deep Learning for Real-Time Fault Detection

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Computers, Materials & Continua 2024年第10期81卷 345-367页

作者： Rehman Ullah khan Fazal Shah Ahmad ali khan Hamza Tahir Faculty of Cognitive Sciences and Human Development Universiti Malaysia SarawakKota Samarahan94300Malaysia School of Computer Science and Engineering Anhui University of Science and TechnologyHuainan232001China Department Electronic Quaid-i-Azam UniversityIslamabad45320Pakistan

Printed Circuit Boards(PCBs)are materials used to connect components to one another to form a working *** play a crucial role in modern electronics by connecting various *** trend of integrating more components onto PCBs is becoming increasingly common,which presents significant challenges for quality control *** the potential impact that even minute defects can have on signal traces,the surface inspection of PCB remains pivotal in ensuring the overall system *** address the limitations associated with manual inspection,this research endeavors to automate the inspection process using the YOLOv8 deep learning algorithm for real-time fault detection in ***,we explore the effectiveness of two variants of the YOLOv8 architecture:YOLOv8 Small and YOLOv8 *** rigorous experimentation and evaluation of our dataset which was acquired from Peking University’s Human-Robot Interaction Lab,we aim to assess the suitability of these models for improving fault detection accuracy within the PCB manufacturing *** results reveal the remarkable capabilities of YOLOv8 Small models in accurately identifying and classifying PCB *** model achieved a precision of 98.7%,a recall of 99%,an accuracy of 98.6%,and an F1 score of *** findings highlight the potential of the YOLOv8 Small model to significantly improve the quality control processes in PCB manufacturing by providing a reliable and efficient solution for fault detection.

关键词： Printed circuit boards(PCB) YOLOv8 YOLOv8 Nano YOLOv8 Small deep learning object detection

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Encoderless Five-phase PMa-SynRM Drive System Based on Robust Torque-speed Estimator with Super-twisting Sliding Mode Control

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CES Transactions on Electrical Machines and Systems 2023年第1期7卷 54-62页

作者： Ghada A.Abdel Aziz Rehan ali khan Power Electronics and Energy Conversion Department Electronics Research InstituteCairo11843Egypt Department of Electrical Engineering University of Science&TechnologyBannu28100Pakistan IEEE

In this paper,a robust torque speed estimator(RTSE)for linear parameter changing(LPC)system is proposed and designed for an encoderless five-phase permanent magnet assisted synchronous reluctance motor(5-phase PMa-SynRM).This estimator is utilized for estimating the rotor speed and the load torque as well as can solve the speed sensor fault problem,as the feedback speed information is obtained directly from the virtual *** addition,this technique is able to enhance the 5-phase PMa-SynRM performance by estimating the load torque for the real time *** stability analysis of the proposed estimator is performed via Schur complement along with Lyapunov ***,for improving the 5-phase PMa-SynRM performance,five super-twisting sliding mode controllers(ST-SMCs)are employed with providing a robust response without the impacts of high chattering problem.A super-twisting sliding mode speed controller(ST-SMSC)is employed for controlling the PMa-SynRM rotor speed,and four super-twisting sliding mode current controllers(ST-SMCCs)are employed for controlling the 5-phase PMa-SynRM *** stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed RTSE and the ST-SMSC with ST-SMCCs approach for a 750-W 5-phase PMa-SynRM under load disturbance,parameters variations,single open-phase fault,and adjacent two-phase open circuit fault conditions.

关键词： Five-phase permanent magnet assisted synchronous reluctance motor Encoderless control Supertwisting sliding mode control Torque-speed estimator

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Exploring the nano-fungicidal efficacy of green synthesized magnesium oxide nanoparticles(MgO NPs)on the development,physiology,and infection of carrot(Daucus carota L.)with Alternaria leaf blight(ALB):Molecular docking

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Journal of Integrative Agriculture 2023年第10期22卷 3069-3080页

作者： Lukman AHAMAD Azmat ali khan Masudulla khan Orudzhev FARID Mahboob ALAM Plant Pathology/Nematology Laboratory Department of BotanyAligarh Muslim UniversityAligarh 202002India Regional Plant Quarantine Station Salt LakeKolkata 700097India Pharmaceutical Biotechnology Laboratory Department of Pharmaceutical ChemistryCollege of PharmacyKing Saud UniversityRiyadh 11451Saudi Arabia Botany Section Women’s CollegeAligarh Muslim UniversityAligarh 202002India Amirkhanov Institute of Physics Dagestan Federal Scientific CenterRussian Academy of SciencesMakhachkala 367003Russia Department of Safety Engineering Dongguk UniversityGyeongju-si 780714Republic of Korea

In this research,green synthesized magnesium oxide nanoparticles(MgO NPs)from lemon fruit extracts and their fungicidal potential was evaluated against Alternaria dauci infection on carrot(Daucus carota L.)under greenhouse *** scanning and transmission electron microscopy(SEM and TEM)and ultra-violet(UV)visible spectroscopy were used to validate and characterize MgO *** crystalline nature of MgONPs was determined using selected area electron diffraction(SAED).MgO NPs triggered substantial antifungal activity against *** when exposed to 50 and 100 mg L^(–1)concentrations but the higher antifungal potential was noticed in 100 mg L^(–1)under invitro *** fungal inoculated plants,a marked decrease in growth,photosynthetic pigments,and an increase in phenol,proline contents,and defense-related enzymes of carrot were seen over control(distilled water).However,foliar application of MgO NPs at 50 and 100 mg L^(–1)resulted in significant improvement of plant growth,photosynthetic pigments,phenol and proline contents,and defense enzymes activity of carrots with and without *** *** of MgO NPs at 100 mg L^(–1)had more plant length(17.11%),shoot dry weight(34.38%),plant fresh weight(20.46%),and root dry weight(49.09%)in carrots when challenged with *** over inoculated *** leaf blight indices and percent disease severity were also reduced in *** inoculated plants when sprayed with MgO *** non-bonding interactions of Alternaria genus protein with nanoparticles were studied using molecular docking.

关键词： green synthesis MgO nanoparticles alternaria leaf blight photosynthetic pigments defense enzymes carrot

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Effect of structural variation in biomass-derived nonfluorinated ionic liquids electrolytes on the performance of supercapacitors

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Journal of Energy Chemistry 2022年第6期31卷 174-184,I0005页

作者： Inayat ali khan Yong-Lei Wang Faiz Ullah Shah Chemistry of Interfaces.Lulea University of Technology.SE-97187 Luled Sweden Department of Materials and Environmental Chemistry.Arrhenius Laboratory.Stockholm University.SE-10691Stockholm.Sweden

There is a growing interest in sustainable and high performance supercapacitors(SCs) operating at elevated temperatures as they are highly demanded in heat-durable electronics. Here, we present a biomass-derived nonfluorinated ionic liquid(IL) [P_(4444)][HFuA] and its structural analogue [P_(4444)][TpA]as electrolytes for supercapacitors comprising multiwall carbon nanotubes and activated charcoal(MWCNTs/AC) mixed carbon composite electrodes. A detailed investigation of the effect of scan rate, temperature, potential window and orientation of ions on the electrodes surfaces is performed. The supercapacitors exhibited relatively lower specific capacitance for both [P_(4444)][HFuA] and [P_(4444)][TpA] ILs at room temperature. However, the specific capacitance has significantly increased with an increase in temperature and potential window. The equivalent serie resistances of the SCs is deceased with increasing temperatures, which is a result of improved ionic conductivities of the IL electrolytes. In CV cycling at60 °C, the capacitor with [P_(4444)][HFuA] IL-based electrolyte retained about 90% of its initial capacitance,while the capacitor with [P_(4444)][TpA] IL-based electrolyte retained about 83% of its initial *** computations revealed that the aromatic [FuA]^(-) and [TpA]^(-) anions displayed perpendicular distribution that can effectively neutralize charges on the carbon surfaces. However, the [HFuA]-anion exhibited somewhat tilted configurations on the carbon electrode surfaces, contributing to their outstanding capacitive performance in electrochemical devices.

关键词： Biomass Ionic liquids Carbon electrodes Supercapacitors Molecular dynamic simulations

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Sustainable pathways to ammonia:a comprehensive review of green production approaches

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Clean Energy 2024年第2期8卷 60-72页

作者： Hafiz Sharjeel Ahmed Zaid Yahya Waqar ali khan ali Faraz University of Engineering and Technology(UET) LahorePakistan Chemical Engineering Department NFC Institute of Engineering and Fertilizer ResearchFaislabadPakistan Chemical Engineering Department Punjab UniversityLahorePakistan

Ammonia production is vital in global industries but faces increasing environmental concerns,necessitating a shift towards sustainable *** review comprehensively explores diverse hydrogen production approaches and their potential impact on sustainable ammonia *** primary focus is investigating hydrogen production methods that enhance both efficiency and sustainability in ammonia synthesis,which is crucial for reducing its environmental ***,the review highlights the pivotal role of catalysts in improving Faradaic efficiency in ammonia synthesis,emphasizing their significance in overall process *** study identifies innovative technologies that have the potential to revolutionize ammonia production while aligning with global sustainability *** a thorough examination of hydrogen production methods and catalytic advances,this review provides valuable insight into greener and more efficient ammonia production *** conclusion,it emphasizes the importance of exploring hydrogen production methods and leveraging catalysts to improve ammonia production sustainability and *** addresses a critical research gap and paves the way for an environmentally responsible and globally aligned ammonia production industry.

关键词： ammonia production green alternatives sustainability catalyst

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Evaluation of antileishmanial,antibacterial and brine shrimp cytotoxic potential of crude methanolic extract of Herb Ocimum basilicum(Lamiacea)

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Journal of Traditional Chinese Medicine 2015年第3期35卷 316-322页

作者： Imran khan Kafeel Ahmad ali Talha Khalil Jangrez khan Yusra ali khan Muhammad Shahab Saqib Muhammad Naveed Umar Hilal Ahmad Department of Biotechnology Quaid-i-Azam University Centre of Biotechnology and Microbiology University of Peshawar Department of Biochemistry Quaid-i-Azam University Islamabad Department of Chemistry University of Malakand Institute of Biotechnology and Genetic Engineering Agriculture UniversityPeshawar

OBJECTIVE:To collect and screen for ethnopharmacological properties(antileishmanial,antibacterial and brine lethality assays) of medicinal plant Ocimum basilicum from Peshawar region(34.008 latitude and 71.57 altitudes).METHODS:In the present study a general antileishmanial activity against Leishmania tropica strain was carried *** antibacterial potential of the plant was performed against 06 gram positive and 06 gram negative *** shrimp cytotoxicity assay at different concentrations were ***:The anti-promastigotes profile of the plant showed good antileishmanial activity exhibited LC_(50) value 21.67 μg/*** result for gram positive antibacterial activity revealed that the *** leaves extract possesses significant inhibitory activity at highest two concentrations ranging from20.66 ± 0.31 to 31.86 ± 0.80 for Clostridium perfringens type C and Bacillus subtitilis,respectively,as compared to the gentamycin(27.36 ± 0.55 and21.80 ± 0.72,respectively).For gram negative bacteria good activity was observed.A highest zone of inhibition was recorded for Pseudomonas aeroginosa(28.83 ± 0.28) atthe highest concentration(10 mg/mL).The LC_(50) value obtained for brine shrimp lethality assay was 91.56 μg/***:The herb basil possesses effective cidal activities which make this plant a good candidate for the isolation of antiprotozoal and antibacterial compounds which may lead to the development of novel drug.

关键词： Ocimum basilicum Cytotoxicity tests,immunologic Anti-bacterial agents Antileishmanial activity

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Long-term sustainability and resilience enhancement of building portfolios

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Resilient Cities and Structures 2023年第2期2卷 13-23页

作者： Ghazanfar ali Anwar You Dong Mustesin ali khan Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Fire Safety Engineering University of Central LancashireDohaQatar

The role of community building portfolios in socioeconomic development and the growth of the built environ-ment cannot be *** to these structures can have far-reaching consequences on socioeconomic and environmental aspects,requiring a long-term perspective for *** communities aim to enhance their resilience and sustainability,there is a cost burden that needs to be *** address this issue,this pa-per proposes a community-level performance enhancement approach that focuses on optimizing the long-term resilience and sustainability of community building portfolios,taking into account recurrent seismic hazards.A Gaussian process surrogate-based multi-objective optimization framework is utilized to optimize the cost objec-tive while considering performance indicators for resilience and *** proposed framework involves using performance-based assessment methods to evaluate the socioeconomic and environmental consequences under stochastic and recurrent seismic hazard *** evaluated indicators are then used to efficiently optimize the community resilience and sustainability,taking into account the retrofit ***,approximate Pareto-optimal solutions are extracted and utilized for *** summary,this paper presents a novel approach for optimizing the long-term resilience and sustainability of community building portfolios by consid-ering recurrent seismic *** proposed framework incorporates performance-based assessment methods and multi-objective optimization techniques to achieve an optimal balance between cost,resilience,and sustain-ability,with the ultimate goal of enhancing community well-being and decision-making in the face of seismic hazards.

关键词： Multi-objective Long-term Seismic hazards Sustainability Resilience Socioeconomic Environmental Buildings Optimization Decision-making

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Conformal Killing Vectors in LRS Bianchi Type Ⅴ Spacetimes

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Communications in Theoretical Physics 2016年第3期65卷 315-320页

作者： Suhail khan Tahir Hussain Ashfaque H.Bokhari Gulzar ali khan Department of Mathematics University of Peshawar Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals

In this note,we investigate conformal Killing vectors(CKVs)of locally rotationally symmetric(LRS)Bianchi type V *** to some integrability conditions,CKVs up to implicit functions of(t,x)are *** these integrability conditions in some particular cases,the CKVs are completely determined,obtaining a classification of LRS Bianchi type V *** inheriting conformal Killing vectors of LRS Bianchi type V spacetimes are also discussed.

关键词： conformal Killing vectors Homothetic vectors conformally flat metrics

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