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Design and Optimization of Interior Permanent Magnet(IPM)Motor for Electric Vehicle Applications

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CES Transactions on Electrical Machines and Systems 2023年第2期7卷 202-209页

作者： Lavanya Balasubramanian Nurul azim Bhuiyan Asad Javied Ashraf A.Fahmy Fawzi Belblidia Johann Sienz the Advanced Sustainable Manufacturing Technologies(ASTUTE 2020)operation Swansea UniversityUK the Department of Electrical Power and Machines Helwan UniversityHelwan 11795Egypt

This paper explores some design parameters of an interior permanent magnet synchronous motor that contribute to enhancing motor *** geometry parameters such as magnet dimension,machine diameter,stator teeth height,and number of poles are analyzed to compare overall torque,power,and torque ripples in order to select the best design parameters and their ***,an open-source software,is used to design and optimize the motor for electric vehicle *** optimization with Non-dominated Sorting Genetic Algorithm(NSGA-Ⅱ),two designs A and B were obtained for two objective functions and the corresponding torque ripples values of the design A and B were later reduced by 32%and 77%.Additionally,the impact of different magnet grades on the output performances is analyzed.

关键词： Electric vehicles IPM motor Magnet grade Optimization Permanent magnet motor Torque ripple

Wild chive oil is an extremely effective larvicide against malaria mosquito vector Anopheles stephensi

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Asian Pacific Journal of Tropical Medicine 2019年第4期12卷 170-174页

作者： Alireza Sanei-Dehkordi Moussa Soleimani-Ahmadi Yaser Salim Abadi azim Paksa Department of Medical Entomology and Vector Control School of Health Hormozgan University of Medical Sciences Infectious and Tropical Diseases Research Center Hormozgan Health Institute Hormozgan University of Medical Sciences Department of Health Services and Health Promotion School of Health Rafsanjan University of Medical Sciences Tabriz University of Medical Sciences

Objective: To assess the chemical composition and mosquito larvicidal potentials of essential oil of wild chive(Allium schoenoprasum L.) against Anopheles ***: In the search for an environmentally safer alternative mosquitoes control, the larvicidal efficacy of essential oil obtained from the leaves of Allium schoenoprasum L. against Anopheles stephensi was determined. The composition of chive essential oil was analyzed by gas chromatography–mass spectrometry. Results: In toxicity assays, the essential oil demonstrated substantial larvicidal activity against larvae of Anopheles stephensi with LC_(50) and LC_(90) values of 2.60, and 7.31 ppm after 24 h of exposure, respectively. Gas chromatography–mass spectrometry analysis of chive essential oil identified 35 components representing more than 97.31% of the total essential oil. The main constituents were sulfur compounds, including diallyl trisulfide(13.72%), 2-ethyl[1,3]dithiane(8.93%), allyl methyl trisulfide(8.77%), and trimethylene trisulfide(6.64%), respectively. Conclusions: This study demonstrated that wild chive essential oil has a rich source of eco-friendly bioactive compounds for use as a mosquito larvicide. The main reason for its extraordinary properties may be related to the high percentage of sulfur compounds.

关键词： Larvicide Allium schoenoprasum Chive Essential oil Gas chromatography–mass spectrometry Anopheles stephensi

Assessment of Genetic Variation Within Indian Mustard (Brassica juncea) Germplasm Using Random Amplified Polymorphic DNA Markers

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Journal of Integrative Plant Biology 2008年第4期50卷 385-392页

作者： Muhammad Ayub Khan Malik Ashiq Rabbani Muhammad Munir Saifullah Khan Ajmal Muhammad azim Malik Oilseed Research Program National Agricultural Research Center Park Road Islamabad 45500 Pakistan Institute of Agri-Biotechnology & Genetic Resources National Agricultural Research Center Park Road Islamabad 45500 Pakistan University of Arid Agriculture Rawalpindi Pakistan

Genetic diversity among 45 Indian mustard （Brassica juncea L.） genotypes comprising 37 germplasm collections, five advance breeding lines and three improved cultivars was investigated at the DNA level using the random amplified polymorphic DNA （RAPD） technique. Fifteen primers used generated a total of 92 RAPD fragments, of which 81 （88%） were polymorphic. Of these, 13 were unique to accession ‘Pak85559＇. Each primer produced four to nine amplified products with an average of 6.13 bands per primer. Based on pairwise comparisons of RAPD amplification products, Nei and Li＇s similarity coefficients were calculated to evaluate the relationships among the accessions. Pairwise similarity indices were higher among the oilseed accessions and cultivars showing narrow ranges of 0.77-0.99. An unweighted pair-group method with arithmetic averages cluster analysis based on these genetic similarities placed most of the collections and oilseed cultivars close to each other, showing a low level of polymorphism between the accessions used. However, the clusters formed by oilseed collections and cultivars were comparatively distinct from that of advanced breeding lines. Genetically, all of the accessions were classified into a few major groups and a number of individual accessions. Advanced breeding lines were relatively divergent from the rest of the accessions and formed independent clusters. Clustering of the accessions did not show any pattern of association between the RAPD markers and the collection sites. A low level of genetic variability of oilseed mustard was attributed to the selection for similar traits and horticultural uses. Perhaps close parentage of these accessions further contributed towards their little diversity. The study demonstrated that RAPD is a simple and fast technique to compare the genetic relationship and pattern of variation among the gene pool of this crop.

关键词： Brassica juncea genetic diversity germplasm oilseed mustard Pakistan random amplified polymorphic DNA.

Invaders’ control on post-disturbance succession in coastal mangroves

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Journal of Plant Ecology 2012年第2期5卷 157-166页

作者： Shekhar R.Biswas Md.Saiful Islam Khan azim U.Mallik Department of Ecology and Evolutionary Biology University of Toronto3359 Mississauga RoadMississaugaOntario L5L1C6Canada United Nations Environment Programme-World Conservation Monitoring Centre(UNEP-WCMC) Cambridge CB30DLUK Forest and Landscape LIFECopenhagen University1958 Frederiksberg CDenmark Department of Biology Lakehead University955 Oliver RoadThunder BayOntario P7B 5E1Canada

Aims In recent years,coastal mangroves have been frequently affected by large disturbances(cyclones,hurricanes,flooding and tsunamis)and post-disturbance vegetation is often dominated by small stature mangrove,mangrove-associate and non-mangrove species potentially affecting ecosystem *** on the processes of mangrove vegetation development and recovery(succession)following normal and large disturbances will benefit practitioners in designing robust ecosystem management/restoration *** we propose a conceptual model of disturbance-mediated succession in *** Based on field observations and species’life history traits,we develop conceptual models of mangrove succession under normal disturbance regime and recently experienced increased frequency of large *** evaluate our conceptual models by conducting a scenario testing *** Findings We suggest two predominant processes affecting mangrove succession after disturbance:propagule limitation due to damage of seed producing mature trees and dispersal barrier resulting from biological invasion associated with large *** argue that large disturbances affect mature trees more than the small-stature non-tree(shrubs,herbs and climbers)species creating a larger propagule shortage for mangrove tree species than non-tree ***,large disturbances facilitate invasion of free-floating aquatics,which may interfere with the flow-facilitated propagule dispersal and seedling establishment of mangrove *** a scenario testing experiment,we have shown that similar levels of disturbance impact vegetation development and recovery differently depending on the presence or absence of invasive *** conclude that since biological invasion is one of the major drivers of post-disturbance mangrove succession,the dimension of biological invasion should be included in prediction,management and restoration of mangrove forests.

关键词： biological invasion cryptic ecological degradation dispersal barrier large disturbances mangrove restoration mangrove succession

Pack Aluminizing of Copper

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Journal of Materials Science & Technology 1997年第2期13卷 127-132页

作者： M.E.Abd El-azim H.M.Soliman (Metallurgy Dept., Atomic Energy Authority Cairo, Egypt) Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Aluminizing of Cu by a pack cementation process was performed to improve its surface *** effect of variation of pack aluminizing temperature from 800 to 900℃ and aluminizing time from 1 to 6 h on the microstructure and the thickness of the aluminide coating of Cu was investigated. Pack aluminizing of Cu significantly improved the microhardness and the oxidation resistance. The microhardness was increased about seven times and the oxidation resistance,after 96 h exposure in air at 900℃, was extremely increased ten times by aluminizing Cu at 900℃ for 3 h.

关键词： VHN Pack Aluminizing of Copper

Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

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Journal of Materials Science & Technology 1997年第5期13卷 383-388页

作者： Soliman, H.M. Ohamed, K.E. Abd El-azim, M.E. Hammad, F.H. Metallurgy Dept. Atomic Energy Authority Cairo Egypt

Low and medium carbon steels were aluminized by the pack aluminizing technique using halideactivated pure-Al and Fe-Al packs. The effect of mixture composition, aluminizing temperatureand time and C content of the steel substrate on the structure and thickness of the aluminidelayer, and on the oxidation resistance was investigated. The optimum oxidation resistance canbe achieved with a low carbon steel substrate when the intermetallic phases Fe3Al and FeAlform the surface of the aluminide layer. In this case, the Al concentration at the surface of thealuminide coating is at least ≥15 wt pct. Formation of high Al concentration phases (FeAl3 andFe2Al5) during aluminizing should be avoided as they tend to embrittle the aluminide layer andreduce its oxidation resistance.

关键词： OO Figure Oxidation Resistance of the Aluminide Coating Formed on Carbon Steels

Anatomical studies on water hyacinth (Eichhornia crassipes (Mart.) Solms) under the influence of textile wastewater

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第10期6卷 991-998页

作者： MAHMOOD Qaisar 郑平 SIDDIQI M. Rehan ISLAM Ejaz ul azim M. Rashid HAYAT Yousaf Department of Environmental Engineering Zhejiang University Department of Botany Forman Christian College Lahore Pakistan Department of Botany Federal Government Postgraduate College H-8 Islamabad Pakistan Department of Maths/Stat/Computer Science North Western Frontier Province Agricultural University Peshawar Pakistan

Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7～50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root *** presence of raphide crystals was noted in parenchyma cells of various organs in treated plants.

关键词： Eichhornia crassipes, Water hyacinth, Textile wastewater, Anatomical studies

Comparative assessment of total polyphenols, antioxidant and antimicrobial activity of different tea varieties of Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2017年第4期7卷 352-357页

作者： Yead Morshed Nibir Ahmed Faisal Sumit Anwarul azim Akhand Nazmul Ahsan Mohammad Shahnoor Hossain Department of Genetic Engineering and Biotechnology University of DhakaDhaka 1000Bangladesh

Objective: To determine the total polyphenol content, antioxidant activity and antibacterial properties of the extracts of different Bangladeshi tea varieties such as flowery broken orange pekoe, broken orange pekoe, red dust and green ***: Total phenolic and flavonoid contents were determined by Folin–Ciocalteu and aluminum chloride colorimetric assay, *** antioxidant capacity was determined by ferric ion reducing antioxidant power and phosphomolybdenum *** activity was evaluated by disc diffusion method in agar plate and subsequently, the minimum inhibitory concentration was determined by broth dilution ***: Total phenolic and flavonoid contents were significantly higher(P < 0.05) in green tea compared to other three black tea *** green tea also showed a higher free radical scavenging and antioxidant activities than all the other tea varieties tested(P < 0.05).In addition, the extracts of all four tea varieties showed inhibitory activity against several pathogenic bacteria and also the same trend of higher antimicrobial activity of green tea than other tea varieties was ***: Taken together, the results of this study demonstrated that Bangladeshi tea,especially the green tea, may act as a substitute for natural antioxidants and as a promising antibacterial agent for beneficial influence in human health.

关键词： Tea extracts Antioxidant activity Antibacterial activity Total phenolic content

Computational Performances of OFDM Using Different FFT Algorithms

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International Journal of Communications, Network and System Sciences 2013年第7期6卷 346-350页

作者： Anwarul azim Department of Electrical and Electronic Engineering East West University Dhaka Bangladesh

In this paper, an intuitive comparison of the computational performance of orthogonal frequency division multiplexing (OFDM) system has been made in terms of complex calculations required using different Fourier transform techniques. The different transform techniques are introduced such as discrete Fourier transform (DFT) and various types of fast Fourier transform (FFT) as 2-radix FFT, 4-radix FFT etc. and the very recent very fast Fourier transform (VFFT). With intuitive mathematical analysis, it has been shown that with the reduced complexity that VFFT can offer, OFDM performance can be greatly improved in terms of calculations needed.

关键词： Orthogonal Frequency Division Multiplexing (OFDM) Discreate Fourier Transform (DFT) Fast Fourier Transform (FFT) Very Fast Fourier Transform (VFFT)