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Observer design for induction motor： an approach based on the mean value theorem

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Frontiers in Energy 2014年第4期8卷 426-433页

作者： mohamed Yacine hammoudi Abdelkarim ALLAG mohamed BECHERIF mohamed BENBOUZID Hamza ALLOUI MSE Laboratory Department of Electrical Engineering University ofBiskra BP 145 Biskra 07000 Algeria FCLab University of Technology of Belfort-Montbdliard CNRS 3539 Femto-ST UMR 6174 Belfort 90010 France LBMS University of Brest Kergoat street CS 93837 29238 BrestCedex 3 France Ecole militaire polytechnique UER ELT Algiers 1611 Algeria

In this paper, observer design for an induction motor has been investigated. The peculiarity of this paper is the synthesis of a mono-Luenberger observer for highly coupled system. To transform the nonlinear error dynamics for the induction motor into the linear parametric varying （LPV） system, the differential mean value theorem combined with the sector nonlinearity transformation has been used. Stability conditions based on the Lyapunov function lead to solvability of a set of linear matrix inequalities. The proposed observer guarantees the global exponential convergence to zero of the estimation error. Finally, the simulation results are given to show the performance of the observer design.

关键词： observer design differential mean value theorem (DMVT) sector nonlinearity transformation linear matrix inequalities (LMI) induction motor

Thermal degradation of diethanolamine at stripper condition for CO2 capture: Product types and reaction mechanisms

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Chinese Journal of Chemical Engineering 2019年第12期27卷 2900-2908页

作者： Idris mohamed Saeed Brahim si Ali Badrul mohamed Jan Wan Jefrey Basirun Shaukat Ali Mazari Ibrahim Ali Obid Birima Department of Chemistry Faculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia Department of Chemical Engineering Faculty of EngineeringUniversity of MalayaKuala Lumpur 50603Malaysia Department of Chemical Engineering Faculty of EngineeringDawood University of Engineering and TechnologyMA Jinnah RoadKarachi 74800Pakistan

Amine-based absorption/stripping is one of the promising technology for CO2 capture from natural and industrial gas *** the process,amines and CO2 undergo irreversible reactions to produce undesired compounds,which cause corrosion,foaming,increased viscosity and breakdown of equipment,ultimately contributing to the economic loss and environmental *** this study,the thermal degradation of aqueous diethanolamine in the presence and absence of dissolved CO2 was *** experiments were performed in stainless steel *** results show that thermal degradation in the absence of CO2 was a slow process;triethanolamine,and tris(2-aminoethyl)amine were only the degradation products identified in the mixture In addition,the rate of degradation was very low,only 3%degradation was observed after 4 *** in the presence of CO2,sixteen degradation products were identified,nine of which were new degradation products reported for the first time in this *** 3-(2-hydroxyethyl)-2-oxazolidinone,1,4-bis(2-hydroxyethyl)piperazine and triethanolamine were the most abundant degradation *** remaining DEA concentration after 4 weeks was about 20%of the total amine *** most probable degradation reactions and their mechanisms are also proposed.

关键词： Diethanolamine CO2 capture Degradation Mechanism

Realization of laser textured brass surface via temperature tuning for surface wettability transition

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光电工程 2017年第6期44卷 587-592页

作者： Huangping Yan mohamed Raiz B Abdul Rashid si Ying Khew Fengping Li Minghui Hong School of Aerospace Engineering Xiamen University Department of Electrical and Computer Engineering National University of Singapore School of Mechanical and Electrical Engineering Wenzhou University

Superhydrophobic surfaces have attracted extensive interests and researches into their fundamentals and potential *** texturing provides the convenience to fabricate the hierarchical micro/nanostructures for ***,after laser texturing,long wettability transition time from superhydrophilicity to superhydrophobicity is a barrier to mass production and practical industrial *** stimuli have been applied to change the surface composition and/or the surface morphology to reduce wettability transition ***,by temperature tuning,wettability transition of laser textured brass surfaces is *** electron microscopy and surface contact angle measurement are employed to characterize the surface morphology and wettability behavior of the textured brass *** low-temperature heating(100℃~150℃),partial deoxidation of the top Cu O layer occurs to form hydrophobic Cu_***,superhydrophobicity without any chemical coating and surface modification could be achieved in a short ***,after low-temperature heating,the low adhesive force between the water droplet and the sample surface is demonstrated for the laser textured brass *** study provides a simple method to fabricate the micro/nanostructure surfaces with controllable wettability for the potential applications.

关键词：纳米结构激光技术发展现状润湿性

Risk Factors and Diabetes Related Complications Frequency in the Population of the Northeastern Morocco

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Open Journal of Epidemiology 2018年第3期8卷 164-185页

作者： Jamila hammoudi Hassana Dahmani Nourel Houda Bouanani Hamid Nouayti Hassane Mekhfi Abdelkhaleq Legssyer mohamed Bnouham Abderrahim Ziyyat Laboratoire de Physiologie Génétique et Ethnopharmacologie Faculté des Sciences Université Mohammed 1<sup>er</sup> Oujda Morocco Centre de Référence de Diabétologie et des Maladies Chroniques Oujda Morocco

Objectives: Diabetes is one of the most challenging health problems in the 21st century that brings a considerable economic burden on worldwide healthcare resources. Indeed, people with diabetes have a higher lifetime healthcare expenditure due to the long-term complications, which include micro and macrovascular complications. This study sought to estimate the frequency of diabetes complications, and to investigate the associated risk factors. Methodology: Data were obtained from the medical records of 2401 diabetic patients followed at the Reference Center of Diabetes and Chronic Diseases (RCD) in Oujda (Morocco) during the period 2006-2011. Results: Our sample of 2401 diabetic patients include 64.7% women. 32% of patients have one or more complications;retinopathy is the most frequent complication (16.8%), followed by nephropathy (12.4%), cardiovascular diseases (5.4%), neuropathy (3.6%) and diabetes foot (2%). Logistic regression in univariate followed by multivariate analysis has showed that age, duration of diabetes and high albuminuria are the major risk factors for the development of diabetic complications in both type 1 and type 2 diabetes. Conclusions: Nearly one third of diabetic patients were affected by at least one diabetic complication;retinopathy is the most common complication in these patients. Strengthening programs to improve diabetes management and to reduce the risk of these complications should be a high priority in order to control the cost of treatment.

关键词： Diabetic Complications Retinopathy Nephropathy North-Eastern Morocco Risk Factors

高温高压下Saraline基超轻完井液黏度预测模型优选

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石油勘探与开发 2016年第5期43卷 793-798页

作者： AMIR Zulhelmi JAN Badrul mohamed WAHAB Ahmad Khairi Abdul KHALIL Munawar ALI Brahim si CHONG Wen Tong University of Malaya Center for Sustainable Infrastructure Development(CsiD) University of Indonesia

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度... 详细信息

以Saraline基超轻完井液为研究对象,分析其黏度在高温高压环境下的变化情况,并优选其高温高压黏度预测模型。测量黏度时温度为298.15~373.15 K,压力为0.10~4.48 MPa,分析测量数据后发现：随着温度的升高,低温下黏度快速下降,高温下黏度降幅较小,且黏度对压力变化不敏感。将实验测量数据与4个常用黏度-温度-压力模型进行拟合,发现利用改进型Mehrotra-Svreck模型和Ghaderi模型预测的黏度值与测量值吻合度较高,能够描述高温高压下Saraline基超轻完井液的黏度特性。与Sarapar基超轻完井液对比后发现,温度对Saraline基超轻完井液黏度的影响更小,压力对Saraline基超轻完井液黏度的影响可以忽略不计,改进型Mehrotra-Svreck模型和Ghaderi模型在各种温度和压力条件下对Saraline基超轻完井液的黏度预测精度优于对Sarapar基超轻完井液的黏度预测。

关键词：高温高压黏度预测超轻完井液 Saraline合成油欠平衡射孔

Parametric study and effect of calcination and carbonation conditions on the CO_2 capture performance of lithium orthosilicate sorbent

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Chinese Journal of Chemical Engineering 2018年第3期26卷 631-641页

作者： Nurul Azrin Zubbri Abdul Rahman mohamed Maedeh Mohammadi Low Carbon Economy (LCE) Research Group School of Chemical Engineering Engineering Campus Universiti Sains Malaysia Faculty of Chemical Engineering Babol Noushirvani University of Technology

The world is currently facing the challenges of global warming and climate change. Numerous efforts have been taken to mitigate CO2 emission, among which is the use of solid sorbents for CO2 capture. In this work, Li4siO4 was synthesised via a sol-gel method using lithium nitrate （LiNO3） and tetraethylorthosilicate （siC8H20O4） as precursors. A parametric study of Li：si molar ratio （1-5）, calcination temperature （600-800℃） and calcination time （1-8 h） were conducted during sorbent synthesis. Calcination temperature （700-800℃） and carbonation temperature （500-700℃） during CO2 sorption activity were also varied to confirm the optimum operating temperature. Sorbent with the highest CO2 sorption capacity was finally introduced to several cyclic tests to study the durability of the sorbent through 10 cycles of CO2 sorption-desorption test. The results showed that the calcination temperature of 800℃ and carbonation temperature of 700℃ were the best operating temperatures, with CO2 sorption capacity of 7.95 mmol CO2·（g sorbent）^-1 （93% of the theoretical yield）. Throughout the ten cyclic processes, CO2 sorption capacity of the sorbent had dropped approximately 16.2% from the first to the tenth cycle, which was a reasonable decline. Thus, it was concluded that Li4siO4 is a potential CO2 solid sorbent for high temperature CO2 capture activity.

关键词： CO2 capture Adsorption Carbon dioxide Lithium orthosilicate Sol-gel Sorption-desorption

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

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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

An Efficient HW/SW Design for Text Extraction from Complex Color Image

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Computers, Materials & Continua 2022年第6期71卷 5963-5977页

作者： mohamed Amin Ben Atitallah Rostom Kachouri Ahmed Ben Atitallah Hassene Mnif LETI(E.N.I.S.) University of SfaxSfaxTunisia Laboratory of informatics Gaspard-MongeA3SIESIEE ParisCNRSGustave Eiffel UniversityFrance National Engineering School of Gabes(ENIG) University of GabesTunisia Department of Electrical Engineering Jouf UniversitySakakaAljoufSaudi Arabia

In the context of constructing an embedded system to help visually impaired people to interpret text,in this paper,an efficient High-level synthesis(HLS)Hardware/Software(HW/SW)design for text extraction using the Gamma Correction Method(GCM)is ***,the GCM is a common method used to extract text from a complex color image and *** purpose of this work is to study the complexity of the GCM method on Xilinx ZCU102 FPGA board and to propose a HW implementation as Intellectual Property(IP)block of the critical blocks in this method using HLS flow with taking account the quality of the text *** IP is integrated and connected to the ARM Cortex-A53 as coprocessor in HW/SW codesign *** experimental results show that theHLS HW/SW implementation of the GCM method on ZCU102 FPGA board allows a reduction in processing time by about 89%compared to the SW *** result is given for the same potency and strength of SW implementation for the text extraction.

关键词： Text extraction GCM HW/SW codesign FPGA HLS flow

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单个纳米孔的宽带光子自旋‐霍尔效应

光电工程 2017年第6期44卷 568-568,659页

作者： Huangping Yan mohamed Raiz B Abdul Rashid si Ying Khew Fengping Li Minghui Hong

光子自旋-霍尔效应（SHEL）指不同自旋态（圆偏振）的光子在一定条件下发生分裂的现象,在光学测量、成像、传感等领域具有重要应用前景。然而,一般条件下SHEL比较微弱,虽然通过谐振能增强分裂强度,但响应带宽受限。近期,微细加工光学技... 详细信息

光子自旋-霍尔效应（SHEL）指不同自旋态（圆偏振）的光子在一定条件下发生分裂的现象,在光学测量、成像、传感等领域具有重要应用前景。然而,一般条件下SHEL比较微弱,虽然通过谐振能增强分裂强度,但响应带宽受限。近期,微细加工光学技术国家重点实验室突破了上述难题,通过理论和实验证明尺度仅为2mm的单个悬链线结构即可产生宽带SHEL,相关文章近期发表于《Light：Science＆Applications》。

关键词：霍尔效应自旋态光子宽带国家重点实验室纳米孔微细加工光学技术光学测量