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On Slide Mode Control of Chaotic Rikitake Two-Disk Dynamo—Chaotic Simulations of the Reversals of the Earth’s Magnetic Field

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International Journal of Modern Nonlinear Theory and Application 2014年第3期3卷 136-143页

作者： Ahmad harb Nabil Ayoub School of Natural Resources Engineering German Jordanian University Amman Jordan

The modern nonlinear theory, bifurcation and chaos theory are used in this paper to analyze the dynamics of the Rikitake two-disk dynamo system. The mathematical model of the Rikitake system consists of three nonlinear differential equations, which found to be the same as the mathematical model of the well-known Lorenz system. The study showed that under certain value of control parameter, the system experiences a chaotic behaviour. The experienced chaotic oscillation may simulate the reversal of the Earth’s magnetic field. The main objective of this paper is to control the chaotic behaviour in Rikitake system. So, a nonlinear controller based on the slide mode control theory is designed. The study showed that the designed controller was so effective in controlling the unstable chaotic oscillations.

关键词： Chaos Theory Nonlinear Control Magnetic Theory Sliding-Mode Control Theory

Teaching English to students of science and technology

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Sino-US English Teaching 2010年第2期7卷 17-29页

作者： Ali Nasser harb Mansouri Department of the English Language and Literature Rustaq College of Applied Sciences Rustaq 329 Sultanate of Oman）

The teaching of English for Science and Technology （EST） is generally regarded as one of the most significant developments in English language pedagogy in recent years. EST is concerned with meeting the specific language needs of learners in various scientific and technological fields. These needs should be taken into consideration when planning and implementing English language courses or specialized courses to students of science and technology. This research is an attempt to investigate some of the problems involved in the teaching and learning of EST and suggest possible solutions. The research will focus on the reading comprehension of scientific and technical texts written in English, the teaching and learning of functional grammar, and the teaching and learning of lexis. These are regarded as some of the most important skills and sub-skills to be acquired by the students of science and technology to help them gain scientific information in English and reach a satisfactory level of achievement in their academic studies. The contention here is that it is in need to adopt a new set of assumptions and criteria specifically relevant to EST instead of employing those of General-English courses being used in the foundation and non-foundation years. This is in line with the basic premise of ESP （English for Special Purpose） and foundation courses which are supposed to prepare students for longer and more difficult tasks in their relevant fields of study. It is hoped that the findings of this research paper will be fruitful and relevant to other ESP courses in addition to those of EST.

关键词： English science technology

Exploring Healthcare Experiences and Needs of Children with ADHD, Jordanian Mothers Perspective: A Phenomenological Study Protocol

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Open Journal of Nursing 2020年第4期10卷 429-438页

作者： Eman harb Inaam Khalaf School of Nursing University of Jordan Amman Jordan Maternal and Child Health Nursing School of Nursing The University of Jordan Amman Jordan

Background: Attention deficit hyperactivity disorder ADHD is a common behavioral problem among children in the world as in Jordan. However, Children with ADHD were significantly less likely to have appropriate health care services when they need health care. Thus, phenomenological study is important and needed as a gap exists in the literature concerning the health care experiences and needs of children with ADHD from the parents’ perspective. Accordingly, this study will conduct to gain an in-depth understanding of the healthcare experiences and needs of children with ADHD. Aim: The aim of the current qualitative study is to explore and describe the health care experiences and health care needs of children with ADHD from their mothers’ perspectives within the context of the phenomenological approach. Study Method: Descriptive phenomenological research design. Semi-structured interview will be conducted with the mothers of children with ADHD who will be recruited purposefully from special Attention Deficit and Hyperactivity Disorders Medical Clinics in order to ensure and to confirm the diagnosis from the specialist there. Data will be transcribed, managed and analyzed using descriptive, phenomenological analysis. The Jordan University Ethics Committee approved the study. Discussion: The findings of this study will make an original contribution to our knowledge about the health care experiences and health care needs of children with ADHD from their mothers’ perspectives within the context of the phenomenological approach, in order to help health care providers in general, and nurses, in particular, to provide optimal health care services for children with ADHD that address the children physical and mental health care needs of the highest priority from mothers’ perspectives.

关键词： ADHD Phenomenology Jordan Qualitative Research

Growth behavior and electronic properties of Ge_(n+1) and AsGe_n(n = 1–20) clusters: a DFT study

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Journal of Semiconductors 2019年第3期40卷 9-17页

作者： M.Benaida K.E.Aiadi S.Mahtout S.Djaadi W.Rammal M.harb Laboratoire de Développement des Energies Nouvelles et Renouvelables en Zones Aride Université de Ouargla Laboratoire de Physique Théorique Faculté des Sciences Exactes Université de Bejaia Faculty of Sciences Lebanese University KAUST Catalysis Center (KCC) Physical Sciences and Engineering Division (PSE) King Abdullah University of Science and Technology (KAUST)

We present a systematic computational study based on the density functional theory(DFT) aiming to high light the possible effects of one As doping atom on the structural, energetic, and electronic properties of different isomers of Ge_(n+1) clusters with n = 1–20 atoms. By considering a large number of structures for each cluster size, the lowest-energy isomers are determined. The lowest-energy isomers reveal three-dimensional structures starting from n = 5. Their relative stability versus atomic size is examined based on the calculated binding energy, fragmentation energy, and second-order difference of energy. Doping Ge_(n+1) clusters with one As atom does not improve their stability. The electronic properties as a function of the atomic size are also discussed from the calculated HOMO–LUMO energy gap, vertical ionization potential, vertical electron affinity, and chemical hardness. The obtained results are significantly affected by the inclusion of one As atom into a Gen cluster.

关键词： density functional theory As–Ge clusters structural properties electronic properties

Split-dose menthol-enhanced PEG vs PEG-ascorbic acid for colonoscopy preparation

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World Journal of Gastroenterology 2015年第6期21卷 1938-1944页

作者： Ala I Sharara Ali H harb Fayez S Sarkis Jean M Chalhoub Rami Badreddine Fadi H Mourad Mahmoud Othman Omar Masri Division of Gastroenterology Department of Internal Medi-cine American University of Beirut Medical Center

AIM:To compare the efficacy and palatability of 4L polyethylene glycol electrolyte(PEG)plus sugar-free menthol candy(PEG+M)vs reduced-volume 2 L ascorbic acid-supplemented PEG(Asc PEG).METHODS:In a randomized controlled trial setting,ambulatory patients scheduled for elective colonoscopy were prospectively *** were randomized to receive either PEG+M or Asc PEG,both splitdosed with minimal dietary *** was assessed on a linear scale of 1 to 5(1=disgusting;5=tasty).Quality of preparation was scored by assignment-blinded endoscopists using the modified Aronchick and Ottawa *** main outcomes were the palatability and efficacy of the *** outcomes included patient willingness to retake the same preparation again in the future and completion of the prescribed ***:Overall,200 patients were enrolled(100patients per arm).PEG+M was more palatable than Asc PEG(76%vs 62%,P=0.03).Completing the preparation was not different between study groups(91%PEG+M vs 86%Asc PEG,P=0.38)but more patients were willing to retake PEG+M(54%vs 40%respectively,P=0.047).There was no significant difference between PEG+M vs Asc PEG in adequate cleansing on both the modified Aronchick(82%vs77%,P=0.31)and the Ottawa scale(85%vs 74%,P=0.054).However,PEG+M was superior in the left colon on the Ottawa subsegmental score(score0-2:94%for PEG+M vs 81%for Asc PEG,P=0.005)and received significantly more excellent ratings than Asc PEG on the modified Aronchick scale(61%vs 43%,P=0.009).Both preparations performed less well in afternoon vs morning examinations(inadequate:29%vs 15.2%,P=0.02).CONCLUSION:4 L PEG plus menthol has better palatability and acceptability than 2 L ascorbic acidPEG and is associated with a higher rate of excellentpreparations;*** identifier:NCT01788709.

关键词： Colonoscopy Bowel preparation Efficacy Tolerabilit

DNA origami mediated electrically connected metal–semiconductor junctions

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Nano Research 2020年第5期13卷 1419-1426页

作者： Basu R.Aryal Dulashani R.Ranasinghe Tyler R.Westover Diana G.Calvopia Robert C.Davis John N.harb Adam T.Woolley Department of Chemistry and Biochemistry Brigham Young UniversityProvoUT 84602USA Department of Chemical Engineering Brigham Young UniversityProvoUT 84602USA Department of Physics and Astronomy Brigham Young UniversityProvoUT 84602USA

DNA-based nanofabrication of inorganic nanostructures has potential application in electronics,catalysis,and *** DNA metallization has generated conductive DNA-assembled nanostructures;however,the use of semiconductors and the development of well-connected nanoscale metal-semiconductor junctions on DNA nanostructures are still at an early ***,we report the first fabrication of multiple electrically connected metal-semiconductor junctions on individual DNA origami by location-specific binding of gold and tellurium *** attachment to DNA origami was via DNA hybridization for Au and by electrostatic interaction for *** gold plating was used to create nanoscale metal-semiconductor interfaces by filling the gaps between Au and Te ***-point electrical characterization indicated that the Au-Te-Au junctions were electrically connected,with current-voltage properties consistent with a Schottky ***-based nanofabrication of metal-semiconductor junctions opens up potential opportunities in nanoelectronics,demonstrating the power of this bottom-up approach.

关键词： current-voltage measurement DNA nanofabrication electroless plating gold nanorods nanoelectronics tellurium nanorods

Improvement of PV/T Based Reverse Osmosis Desalination Plant Performances Using Fuzzy Logic Controller

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International Journal of Modern Nonlinear Theory and Application 2016年第1期5卷 11-27页

作者： Mahmoud Ammous Sana Charfi Ahmad harb Maher Chaabene University of Sfax Sfax Tunisia School of Natural Resources Engineering and Management German Jordanian University Amman Jordan

Photovoltaic based reverse osmosis desalination systems (PV/RO) present an effective method of water desalination especially in remote areas. The increase of the feed water temperature leads to an amelioration of the plant performances. Photovoltaic Thermal Collector (PV/T) represents an ideal power source as it provides both electric and thermal energies for the reverse osmosis process. Nevertheless, PV/T based RO plants should be controlled in order to solve operation problems related to electrical efficiency, reverse osmosis membrane, produced water and the rejected salts. This paper suggests a fuzzy logic controller for the flow rate of the circulating fluid into the PV/T collectors so as to ameliorate the system performances. The designed controller has improved the PV/T field electrical efficiency and preserved the reverse osmosis membrane which upgrades the system productivity. LABVIEW software is used to simulate the controlled system and validate the effectiveness of the controller.

关键词： PV/T Collector Reverse Osmosis Control Fuzzy Logic Controller

28-nm UTBB FD-SOI vs. 22-nm Tri-Gate FinFET Review: A Designer Guide—Part I

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Circuits and Systems 2017年第4期8卷 93-110页

作者： Ali Mohsen Adnan harb Nathalie Deltimple Abraham Serhane Department of Electrical and Electronics Engineering Lebanese International University Beirut Lebanon IMS Laboratory University of Bordeaux Talence cedex France Department of Industrial Engineering Lebanese International University Beirut Lebanon

Nowadays, transistor technology is going toward the fully depleted architecture;the bulk transistors are becoming more complex in manufacturing as the transistor size is becoming smaller to achieve the high performance especially at the node 28 nm. This is the first of two papers that discuss the basic drawbacks of the bulk transistors and explain the two alternative transistors: 28 nm UTBB FD-SOI CMOS and the 22 nm Tri-Gate FinFET. The accompanying paper, Part II, focuses on the comparison between those alternatives and their physical properties, electrical properties, and reliability tests to properly set the preferences when choosing for different mobile media and consumers’ applications.

关键词： UTBB FD-SOI: Ultra-Thin Body and Box Fully Depleted Silicon on Insulator Tri-Gate FinFET DIBL: Drain Induced Barrier Lowering

Risk prediction rule for advanced neoplasia on screening colonoscopy for average-risk individuals

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World Journal of Gastroenterology 2020年第37期26卷 5705-5717页

作者： Ala I Sharara Ali El Mokahal Ali H harb Natalia Khalaf Fayez S Sarkis Mustapha M El-Halabi Nabil M Mansour Ahmad Malli Robert Habib Division of Gastroenterology Department of Internal MedicineAmerican University of Beirut Medical CenterBeirut 11072020Lebanon Digestive and Liver Diseases Division University of Texas-SouthwesternDallasTX 75390United States Division of Gastroenterology Department of Internal MedicineBaylor College of MedicineHoustonTX 77030United States Division of Gastroenterology and Hepatology University of Kansas Medical CenterKansas CityMO 66160United States Division of Gastroenterology St Elizabeth HealthcareCrestview HillsKY 41017United States Department of Internal Medicine Section of Gastroenterology and HepatologyBaylor College of MedicineHoustonTX 77030United States Gastroenterology Hennepin HealthcareMinneapolisMN 55404United States Department of Internal Medicine American University of BeirutBeirut 11072020Lebanon

BACKGROUND In resource-limited countries,risk stratification can be used to optimize colorectal cancer *** prospective risk prediction models exist for advanced neoplasia(AN)in true average-risk *** To create and internally validate a risk prediction model for detection of AN in METHODS Prospective study of asymptomatic individuals undergoing first screening *** characteristics including diet,exercise and medications were *** logistic regression was used to elucidate risk factors for AN(adenoma≥1 cm,villous histology,high-grade dysplasia or carcinoma).The model was validated through bootstrapping,and discrimination and calibration of the model were *** 980 consecutive individuals(51%F;49%M)were *** and AN detection rates were 36.6%(F 29%:M 45%;P<0.001)and 5.1%(F 3.8%;M 6.5%)*** multivariate analysis,predictors of AN[OR(95%CI)]were age[1.036(1.00-1.07);P=0.048],BMI[overweight 2.21(0.98-5.00);obese 3.54(1.48-8.50);P=0.018],smoking[<40 pack-years 2.01(1.01-4.01);≥40 pack-years 3.96(1.86-8.42);P=0.002],and daily red meat consumption[2.02(0.92-4.42)P=0.079].Nomograms of AN risk were developed in terms of risk factors and age separately for normal,overweight and obese *** model had good discrimination and *** The prevalence of adenoma and AN in average-risk Lebanese individuals is similar to the ***,smoking,and BMI are important predictors of AN,with obesity being particularly *** external validation is needed,this model provides an important platform for improved risk-stratification for screening programs in regions where universal screening is not currently employed.

关键词： Colon Adenoma Cancer Risk factors