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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

Quantification of silicon (si) and silicon Dioxide (siO₂) from the Nafud Desert-Al-Qassim Region, Kingdom of Saudi Arabia Using XRD Analysis

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Advances in Materials Physics and Chemistry 2024年第5期14卷 67-75页

作者： Nagwa Ibrahim mohamed Department of Physics College of Science Qassim University Buraydah Saudi Arabia

This research was conducted in the Qassim region, Kingdom of Saudi Arabia. The goal of this research is to determine the percentage of silicon in the Rub al-Khali desert. Samples were collected from four cities located in the Al-Qassim Region of Saudi Arabia (Uyun Al-Jawa, Al-Fuwailiq, Al-Sulaibiya, and Al-Qawara), from three distinct depths (the earth’s surface, 50 cm, and 100 cm). The percentages of silicon in these places vary between the highest value for silicon dioxide, which is 74.47 m/m%, and 34.8 m/m% for silicon in Al-Qawara city at a depth of 100 cm. We used an x-ray fluorescence (XRF) instrument to evaluate the samples. There are high percentage of both silica and silicon in the Nafud desert. Studies have shown that these ratios can help investors benefit from an element of silicon and silicon dioxide, so the sands of the Nafud desert is sufficient for extracting silicon and silica in huge quantities. This may transform the Kingdom into a leading country in the global computer technology industry that depends on silicon extracted from the desert sands, the most important of which are microcomputer data processing devices.

关键词： silica Sand Dispersive X-Ray Fluorescence (EDXRF) Analyzer Solar Cells Nafud Desert Al-Qawwarh

CuO–TiO_(2) based self-powered broad band photodetector

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Nano Materials Science 2024年第3期6卷 345-354页

作者： Chiranjib Ghosh Arka Dey Iman Biswas Rajeev Kumar Gupta Vikram singh Yadav Ashish Yadav Neha Yadav Hongyu Zheng mohamed Henini Aniruddha Mondal Department of Physics National Institute of Technology DurgapurWest BengalIndia Department of Physics University of Petroleum&Energy Studies DehradunUttarakhandIndia Babasaheb Bhimrao Ambedkar University Lucknow226031India Center for Advanced Laser Manufacturing(CALM) Shandong University of TechnologyZibo255000PR China School of Physics and Astronomy University of NottinghamNottinghamNG72RDUnited Kingdom

An efficient room-temperature self-powered,broadband(300 nm–1100 nm)photodetector based on a CuO–TiO_(2)/TiO_(2)/p-si(100)heterostructure is *** CuO–TiO_(2)nanocomposites were grown in a two-zone horizontal tube furnace on a 40 nm TiO_(2)thin film deposited on a p-type si(100)*** CuO–TiO_(2)/TiO_(2)/p-si(100)devices exhibited excellent rectification characteristics under dark and individual photoillumination *** devices showed remarkable photo-response under broadband(300–1100 nm)light illumination at zero bias voltage,indicating the achievement of highly sensitive self-powered photodetectors at visible and near-infrared light *** maximum response of the devices is observed at 300 nm for an illumination power of 10 *** response and recovery times were calculated as 86 ms and 78 ms,***,under a small bias,the devices showed a prompt binary response by altering the current from positive to negative under illumination *** main reason behind this binary response is the low turn-on voltage and photovoltaic characteristics of the *** illumination conditions,the generation of photocurrent is due to the separation of photogenerated electron-hole pairs within the built-in electric field at the CuO–TiO_(2)/TiO_(2)*** characteristics make the CuO–TiO_(2)/TiO_(2)broadband photodetectors suitable for applications that require high response speeds and self-sufficient functionality.

关键词： Self-powered CuO–TiO_(2) nanocomposite Broadband photodetector Two-zone horizontal tube furnace Responsivity

冠状动脉钙积分CT扫描检测无冠心病史糖尿病病人的无症状性心肌梗死脂肪瘢痕

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国际医学放射学杂志 2024年第2期 248-249页

作者： S.Boccalini M.Teulade E.Paquet S.si-mohamed F.Rapallo C.Moreau-Triby 李晓舒

摘要目的评估冠状动脉钙化CT(CAC-CT)检测的无冠心病（CHD）病史糖尿病病人心肌内脂肪瘢痕（IMFS）的患病率，IMFS最有可能提示既往发生的无症状心肌梗死

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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

Quantification of silicon (si) and silicon Dioxide (siO2) from the Nafud Desert-Al-Qassim Region, Kingdom of Saudi Arabia Using XRD Analysis

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

Advances in Materials Physics and Chemistry（材料物理与化学进展） 2024年第5期 67页

作者： Nagwa Ibrahim mohamed

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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