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An Efficient Text Recognition System from Complex Color Image for Helping the Visually Impaired Persons

Computer Systems Science & Engineering 2023年第7期46卷 701-717页

作者： Ahmed ben Atitallah Mohamed Amin ben Atitallah Yahia Said Mohammed Albekairi Anis Boudabous Turki MAlanazi Khaled Kaaniche Mohamed Atri Department of Electrical Engineering College of EngineeringJouf UniversitySakakaSaudi Arabia Laboratory of Informatics Gaspard-MongeA3SIESIEE ParisCNRSGustave Eiffel UniversityFrance LETI ENISUniversity of SfaxSfaxTunisia Remote Sensing Unit College of EngineeringNorthern Border UniversityArarSaudi Arabia Laboratory of Electronics and Microelectronics(LR99ES30) University of MonastirTunisia Department of Computer Engineering and Networks College of Computer and Information SciencesJouf UniversitySakakaSaudi Arabia College of Computer Sciences King Khalid UniversityAbhaSaudi Arabia

The challenge faced by the visually impaired persons in their day-today lives is to interpret text from *** this context,to help these people,the objective of this work is to develop an efficient text recognition system that allows the isolation,the extraction,and the recognition of text in the case of documents having a textured background,a degraded aspect of colors,and of poor quality,and to synthesize it into *** system basically consists of three algorithms:a text localization and detection algorithm based on mathematical morphology method(MMM);a text extraction algorithm based on the gamma correction method(GCM);and an optical character recognition(OCR)algorithm for text recognition.A detailed complexity study of the different blocks of this text recognition system has been *** this study,an acceleration of the GCM algorithm(AGCM)is *** AGCM algorithm has reduced the complexity in the text recognition system by 70%and kept the same quality of text recognition as that of the original *** assist visually impaired persons,a graphical interface of the entire text recognition chain has been developed,allowing the capture of images from a camera,rapid and intuitive visualization of the recognized text from this image,and text-to-speech *** text recognition system provides an improvement of 6.8%for the recognition rate and 7.6%for the f-measure relative to GCM and AGCM algorithms.

关键词： Text recognition system GCM AGCM OCR color images graphical interface

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3D Photo-fabrication for Tissue Engineering and Drug Delivery

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Engineering 2015年第1期1卷 90-112页

作者： Rúben f.Pereira Paulo J.Bártolo Centre for Rapid and Sustainable Product Development (CDRsp) Polytechnic Institute of Leiria Instituto de Investiga??o e Inova??o em Saúde (I3S) Universidade do Porto Instituto Nacional de Engenharia Biomédica (INEB) Universidade do Porto Instituto de Ciências Biomédicas Abel Salazar (ICBAS) Universidade do Porto School of Mechanical Aerospace and Civil EngineeringUniversity of Manchester Manchester Institute of Biotechnology University of Manchester

The most promising strategies in tissue engineering involve the integration of a triad of biomaterials, living cells, and biologically active molecules to engineer synthetic environments that closely mimic the healing milieu present in human tissues, and that stimulate tissue repair and regeneration. To be clinically effective, these environments must replicate, as closely as possible, the main characteristics of the native extracellular matrix(ECM) on a cellular and subcellular scale. Photo-fabrication techniques have already been used to generate 3D environments with precise architectures and heterogeneous composition, through a multi-layer procedure involving the selective photocrosslinking reaction of a light-sensitive prepolymer. Cells and therapeutic molecules can be included in the initial hydrogel precursor solution, and processed into 3D constructs. Recently, photofabrication has also been explored to dynamically modulate hydrogel features in real time, providing enhanced control of cell fate and delivery of bioactive compounds. This paper focuses on the use of 3D photo-fabrication techniques to produce advanced constructs for tissue regeneration and drug delivery applications. State-of-the-art photo-fabrication techniques are described, with emphasis on the operating principles and biofabrication strategies to create spatially controlled patterns of cells and bioactive factors. Considering its fast processing, spatiotemporal control, high resolution, and accuracy, photo-fabrication is assuming a critical role in the design of sophisticated 3D constructs. This technology is capable of providing appropriate environments for tissue regeneration, and regulating the spatiotemporal delivery of therapeutics.

关键词： 3D photo-fabrication biomaterials tissueengineering drug delivery

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Red fluorescent siloles with aggregation-enhanced emission characteristics

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Science China Chemistry 2016年第6期59卷 699-706,711+706页

作者： Bin Chen Han Nie Rongrong Hu Anjun Qin Zujin Zhao ben-Zhong Tang State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China Department of Chemistry Hong Kong University of Science & Technology Kowloon Hong Kong China Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction Hong Kong China

A series of new red fluorescent siloles consisting of a silole core and dimesitylboranyl substituent connected with a furan, thiophene, and selenophene bridges were synthesized and characterized. The optical properties, electronic structures, and electroluminescence （EL） performances were investigated. The emission wavelengths were red-shifted from the siloles with furan, to those with thiophene, and then selenophene. The thiophene, and selenophene-containing siloles, （MesB）2DTTPS, and （MesB）zDSTPS, showed the typical aggregation-enhanced emission （AEE） feature, while furan-containing one, （MesB）2DfTPS, showed slight emission decrease as the aggregate formation. Theoretical calculations were carried out to explain the difference in the optical properties. Undoped OLEDs using these red siloles as light-emitting layers were fabricated. The device of （MesB）2DTTPS exhibited the best performance. It radiated red EL emission at 589 nm, and afforded good maximum luminance, current, power, and external quantum efficiency of 13300 cd m^-2, 4.3 cd A^-1, 2.9 lm W^-1, and 1.8%, respectively.

关键词： silole organoboron aggregation-enhanced emission red fluorescence organic light-emitting diodes

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GMLP-IDS: A Novel Deep Learning-Based Intrusion Detection System for Smart Agriculture

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Computers, Materials & Continua 2023年第10期77卷 379-402页

作者： Abdelwahed Berguiga Ahlem Harchay Ayman Massaoudi Mossaad ben Ayed Hafedh Belmabrouk Department of Computer Science College of Science and Arts in GurayatJouf UniversitySakakahSaudi Arabia Olive Research Center Jouf UniversitySakakahSaudi Arabia Department of Electronic Industrial ENISoSousse UniversitySousseTunisia Department of Physics College of Science at ZulfiMajmaah UniversityMajmaahSaudi Arabia

Smart Agriculture,also known as Agricultural 5.0,is expected to be an integral part of our human lives to reduce the cost of agricultural inputs,increasing productivity and improving the quality of the final ***,the safety and ongoing maintenance of Smart Agriculture from cyber-attacks are vitally *** provide more comprehensive protection against potential cyber-attacks,this paper proposes a new deep learning-based intrusion detection system for securing Smart *** proposed Intrusion Detection System IDS,namely GMLPIDS,combines the feedforward neural network Multilayer Perceptron(MLP)and the Gaussian Mixture Model(GMM)that can better protect the Smart Agriculture ***-IDS is evaluated with the CIC-DDoS2019 dataset,which contains various Distributed Denial-of-Service(DDoS)*** paper first uses the Pearson’s correlation coefficient approach to determine the correlation between the CIC-DDoS2019 dataset characteristics and their corresponding class ***,the CIC-DDoS2019 dataset is divided randomly into two parts,i.e.,training and testing.75%of the data is used for training,and 25%is employed for *** performance of the newly proposed IDS has been compared to the traditional MLP model in terms of accuracy rating,loss rating,recall,and f1 *** are handled on both binary and multi-class classification *** results revealed that the proposed GMLP-IDS system achieved more than 99.99%detection accuracy and a loss of 0.02%compared to traditional ***,evaluation performance demonstrates that the proposed approach covers a more comprehensive range of security properties for Smart Agriculture and can be a promising solution for detecting unknown DDoS attacks.

关键词： Drones DDoS attacks Internet of Things deep learning multilayer perceptron gaussian mixture model Industry 5.0 Agricultural 5.0

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Interspecific hybridization between Bursaphelenchus xylophilus and Bursaphelenchus mucronatus

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Journal of forestry Research 2019年第2期30卷 699-707页

作者： Kan-Cheng Liu Ailing ben Zhengmin Han Ye Guo Dongxia Cao College of forestry Nanjing Forestry University Nanjing Xiaozhuang University

Bursaphelenchus xylophilus is the pathogen that causes pine wilt disease, which has greatly damaged forests and ecosystems in countries of East Asia and *** mucronatus is closely related to B. xylophilus in morphology and host plant specificity. A longrunning debate has existed regarding whether these two species can successfully produce hybrid offspring. In the present study, we performed in the laboratory, hybridization of two B. xylophilus nematode isolates from China and Japan and three B. mucronatus isolates from China, Japan and france. Nematode isolates of B. xylophilus were successfully crossed with B. mucronatus isolates, and the rate of hybridization was relatively high; however, some hybrid offspring died. Successful hybridization occurred between B. xylophilus and B. mucronatus isolates from China, and 22 generations of hybrids were produced. All f1 hybrids could be backcrossed with their parents and produce offspring. Variation in mucro length among the hybrid offspring and their parents was observed. The hybrid offspring and their parents were inoculated into 3-months-old black pine(Pinus tunbergii) seedlings. Weaker pathogenicity of hybrid offspring was observed compared with that of their parents, and significantly fewer offspring nematodes than parents were reisolated from pines. Therefore, the offspring of B. xylophilus and B. mucronatus may exist in the forest and could influence disease epidemics.

关键词： Bursaphelenchus xylophilus Bursaphelenchus mucronatus Interspecific hybridization Variation

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Integrated Mineral Analysis of sandstone and dolomite formations using different chelating agents during matrix acidizing

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Petroleum 2019年第1期5卷 67-76页

作者： Mian Umer Shafiq Hisham Khaled ben Mahmud Mohsen Ghasemi Curtin University CDT 25098009 MiriSarawakMalaysia Curtin University Kent StreetBentleyPerth6102Australia

Mineral analysis plays a major role in the successful matrix acidizing as it shows the change in physiochemical changes in the formation due to the reaction with fluids *** of the reservoir can be altered by injecting mineral acids during matrix *** various complications are connected during the application of these acids such as environmental hazards,corrosion of pipes and tubings,precipitation of fluosilicates and fast spending of *** mitigate these problems,chelating agents have been applied as an alternative by different *** this study,three different chelating agents EDTA,GLDA and HEDTA were applied to stimulate sandstone and dolomite *** pH value of these chelates ranges from 1.7 to 3 and is measured before and after core flooding to observe physiochemical *** flooding experiments under 180f temperature were performed at a constant flow rate of 1 ml/min on core samples having dimensions(3 inch1.5 inch).Porosity,permeability,Inductively Coupled Plasma(ICP),and TESCAN Integrated Mineral Analysis(TIMA)were employed to measure changes in formation properties such as morphology,topology and *** reacted sample of acids was analyzed for sodium,potassium,calcium,aluminium,magnesium,and iron using the ICP technique to find the capability of these chelates to remove positive *** found to be effective in chelating iron,calcium and magnesium and it also removed some amount of aluminium ions from the sandstone *** and porosity analysis concluded that HEDTA is more efficient in creating new big pore *** analysis confirms that HEDTA is effective in dissolving quartz and other positive ions while dissolved a large amount of calcium and sodium from the sandstone as compared to other *** analysis also concluded that HEDTA is effective in increasing porosity of sandstone formation while GLDA is effective in dolomites.

关键词： sandstone matrix porosity

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Contribution to the understanding of the performance differences between commercial current collectors in Li–S batteries

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Journal of Energy Chemistry 2021年第11期30卷 295-306,I0007页

作者： A.benitez f.Luna-Lama ACaballero E.Rodriguez-Castellon J.Morales Dpto.Química Inorgánica e Ingeniería Química Instituto Universitario de Nanoquímica(IUNAN)Universidad de Córdoba14071 CórdobaSpain Dpto.de Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071 MálagaSpain

Lithium–sulfur batteries have been recognised as highly promising next-generation batteries, due to their low cost and high theoretical energy density. Despite numerous advances in this technology over the last decade, its commercialisation is still a challenge that has not yet been achieved. Many efforts have been made to improve the problems that these batteries present, mainly by investigating different cathode manufacturing strategies, testing novel Li anodes, new additives in the electrolytes, and modified separators or interlayers. However, the characteristics of the current collectors used in the preparation of the electrodes have been rarely addressed. Three commercial collectors are commonly used in basic research on Li–S batteries: Al foil, carbon coated Al foil (Al-C), and carbon paper (gas diffusion layer, GDL). In this work, a detailed study of the electrochemical response of these commercial collectors has been carried out. The tests were carried out on two S composites formed by carbons of a different natures, commercial carbon black and synthetic N-doped graphene. In addition, the S impregnation method was different, using either melt diffusion at 155 ℃ or ethylenediamine as S solvent, respectively. In both systems, the results were similar – the electrodes supported on GDL delivered higher specific capacities than those supported on Al and Al-C, with minimal differences between the two. Of the different collector properties examined to explain this behaviour, namely Al corrosion, electrical conductivities, surface-level composition, and surface texture, only the latter had a significant effect in the performance of GDL-based electrodes. SEM images revealed a rough and cracked surface formed by the agglomerated carbon particles that give rise to a complex pore system, predominantly consisting of macropores. All of these features are beneficial for a better anchoring of the active material on the collector surface, in addition to enhancing the wettabi

关键词： Current collector Carbon paper Aluminum foil Lithium–sulfur battery

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Preparation and Properties of Modified Nanofiber Membrane for Lithium Sulfur Battery

Preparation and Properties of Modified Nanofiber Membrane fo...

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作者： Eya ben Ticha 天津工业大学

学位级别：硕士

锂硫电池具有较高的理论比容量和能量密度,分别达到1675 mAh/g和2600 Wh/kg,具有原料来源广,无毒无害,成本低的优点,受到越来越多的学者的关注。作为电池的重要元素之一,电池隔膜主要起到将电池的正极和负极分开,并避免了电池的短路。目... 详细信息

锂硫电池具有较高的理论比容量和能量密度,分别达到1675 mAh/g和2600 Wh/kg,具有原料来源广,无毒无害,成本低的优点,受到越来越多的学者的关注。作为电池的重要元素之一,电池隔膜主要起到将电池的正极和负极分开,并避免了电池的短路。目前,商业锂电池隔膜仍主要基于聚烯烃膜。然而,这样的隔膜具有差的电解液润湿性和保液性,以及差的热尺寸稳定性,并且可能导致电池短路甚至爆炸。特别地,难以抑制锂硫电池多硫化物的“穿梭效应”。因此,近年来,开发出具有高孔隙率,优异的电解质润湿性和高温稳定性的新型电池隔膜已成为锂硫电池领域的研究重点。电纺PMIA纳米纤维膜由于其优异的耐高温性,高比表面积和机械强度,已成为目前最具研究潜力的新型锂硫电池隔膜。然而,由于低亲液性和保液性,自放电严重,严重阻碍了其进一步发展。因此,为了改善此类问题并更好地改善电化学性能,本主题主要在两个方面的研究:(1)以高性能的PMIA为基材,通过静电纺丝技术制备了SiO-fco-doped PMIA复合凝胶化隔膜。f掺杂的PMIA膜与SiO-f共掺杂的PMIA膜相结合,使所设计的功能隔膜具有极高的电解质吸收能力,并保留了出色的热稳定性和良好的耐收缩性,并有效地通过物理限域和化学吸附限制多硫化物的穿梭效应。使运用所制备的隔膜所组装的Li-S电池在1274.8 mAhg-1时具有出色的初始放电容量,并具有出色的循环稳定性,在0.5 C倍率下,所组装电池经过600次循环后具有出色的容量保持率814.8 mAhg-1和库仑效率98.42%。(2)利用静电纺丝技术制备含MOfs氟共掺杂芳纶纳米纤维膜,采用SEM、XRD和fTIR等表征了其微观结构,并考察了MOfs含量对纤维膜力学性能、保液率、亲液性和热稳定性等的影响,初步对含不同MOfs比例的隔膜所组装的电池进行电化学性能测试。结果表明,所制备的铝基MOfs纯度较高,其掺杂的含氟芳纶纳米纤维膜具有较高的热稳定性和良好的亲液性与保液率。根据初步的交流阻抗测试表明,3 wt%MOfs掺杂的含氟芳纶纳米纤维膜具有更好的电化学性能。该锂硫电池的电荷转移电阻以及界面阻抗较小,且具有极小的Warburg阻抗。运用所制备的隔膜所组装的Li-S电池,其PMIA,f-doped PMIA和MOf(3%)-f doped PMIA的电池循环,所组装电池的初始比容量容量分别为1075.6 mAhg、1093.1 mAhg和1133.2 mAhg。所组装的电池在经过300次循环后的放电比容量为520.4 mAhg、613.9 mAhg和782.6 mAhg。

关键词：锂硫电池隔膜抑制“穿梭效应” 抑制锂枝晶生长锂枝晶凝胶聚合物电解质 PMIA膜 f掺杂的PMIA膜 MOf-f共掺杂的PMIA膜

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Mesenchymal stem cell therapy for retinal ganglion cell neuroprotection and axon regeneration

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Neural Regeneration Research 2015年第3期10卷 371-373页

作者： ben Mead ben A.Scheven Neurotrauma Research Group Neurobiology SectionSchool of Clinical and Experimental MedicineUniversity of Birmingham School of Dentistry University of Birmingham

Retinal ganglion cells （RGCs） are responsible for propagat- ing signals derived from visual stimuli in the eye to the brain, along their axons within the optic nerve to the superior colliculus, lateral geniculate nucleus and visu- al cortex of the brain. Damage to the optic nerve either through trauma, such as head injury, or degenerative dis- ease, such as glaucoma causes irreversible loss of function through degeneration of non-regenerating RGC axons and death of irreplaceable RGCs, ultimately leading to blindness （Berry et al., 2008）. The degeneration of RGCs and their axons is due to the loss of the necessary source of retrogradely transported neurotrophic factors （NTfs） being hindered by axonal injury. NTfs are survival factors for neurons and play a pivotal part in axon regeneration. Stem cells particularly mesenchymal stem cells （MSCs） have been shown to possess a natural intrinsic capacity for paracrine support, releasing multiple signalling mol- ecules including NTfs. By transplanting MSCs into the vitreous, they are positioned adjacent to the injured reti- na to provide paracrine-mediated therapy for the retinal neuronal cells （Johnson et al., 2010a; Mead et al., 2013）. Additionally, MSCs may be pre-differentiated into sup- portive glial-like cells, such as Schwann cells, which could further increase their potential for paracrine support of injured neurons （Martens et al., 2013）. Thus, MSCs have received considerable attention as a new cellular therapy for both traumatic and degenerative eye disease, acting as an alternative source of NTfs, protecting injured RGCs and promoting regeneration of their axons （figure 1）.

关键词： DPSCs RGCs BMSCs stem Mesenchymal stem cell therapy for retinal ganglion cell neuroprotection and axon regeneration cell

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Audit pricing and nature of controlling shareholders:Evidence from france

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China Journal of Accounting Research 2013年第1期6卷 21-34页

作者： Chiraz ben Ali Cdric Lesage IPAG Business School France HEC Paris France

This study examines whether auditors are employed as a monitoring mechanism to mitigate agency problems arising from different types of controlling shareholders. In a context of concentrated ownership and poor investor protection, controlling shareholders can easily expropriate wealth from minority shareholders and profit from private benefits of control. However, this agency conflict has been rarely studied, as the most commonly assumed agency conflict occurs between managers and shareholders. Using an audit fee model derived from , we study the impact of the nature of controlling shareholders on audit fees in french listed firms. Our results show: (1) a negative relationship between audit fees and government shareholdings; (2) a positive relationship between audit fees and institutional shareholdings; and (3) no relationship between audit fees and family shareholdings. These results illustrate the mixed effects of the nature of ownership on audit fees.

关键词： Audit fees Controlling shareholder identity Minority expropriation Agency conict

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