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An Iterative Scheme of Arbitrary Odd Order and Its Basins of Attraction for Nonlinear Systems

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Computers, Materials & Continua 2021年第2期66卷 1427-1444页

作者： Obadah said Solaiman Ishak Hashim Department of Mathematical Sciences Universiti Kebangsaan MalaysiaBangi Selangor43600Malaysia

In this paper,we propose a fifth-order scheme for solving systems of nonlinear *** convergence analysis of the proposed technique is *** proposed method is generalized and extended to be of any odd order of the form 2n*** scheme is composed of three steps,of which the first two steps are based on the two-step Homeier’s method with cubic convergence,and the last is a Newton step with an appropriate approximation for the *** iteration of the presented method requires the evaluation of two functions,two Fréchet derivatives,and three matrix inversions.A comparison between the efficiency index and the computational efficiency index of the presented scheme with existing methods is *** basins of attraction of the proposed scheme illustrated and compared to other schemes of the same *** test problems including large systems of equations are considered to compare the performance of the proposed method according to other methods of the same *** an application,we apply the new scheme to some real-life problems,including the mixed Hammerstein integral equation and Burgers’*** and examples show that the presented method is efficient and comparable to the existing techniques of the same order.

关键词： System of nonlinear equations root finding method iterative method order of convergence Burgers’equation

On the Optimal Design of Cable Driven Parallel Robot with a Prescribed Workspace for Upper Limb Rehabilitation Tasks

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Journal of Bionic Engineering 2019年第3期16卷 503-513页

作者： Laribi Med Amine Carbone Giuseppe Zeghloul said Department of GMSC Pprime Institute CNRS-University of Poitiers - ENSMA - UPR 3346 Poitiers France Department of Mechanical Energy and Management Engineering University of Calabria 87036 Rende Italy CESTER Technical University of Cluj-Napoca Muncii Ave. 103-105 400641 Cluj-Napoca Romania

This paper deals with an optimization approach to design a cable driven parallel robot intended for upper limb rehabilitation tasks. The cable driven parallel robots have characteristics that make them best candidate for rehabilitation exercise purposes such as large workspace, re-configurable architecture, portability and cost effectiveness. Here, both the cable tensions that are needed to move a wristband as well as the workspace need to be carefully optimized for fulfilling the prescribed operation tasks. A specific case of study is addressed in this work by referring to LA RM wire driven exercising device (LAWEX), which is applied to upper limbs exercises. To that end, a motion capture system is used to collect quantitative data on the prescribed workspace of a human upper limb. A specific optimization problem is settled up for considering combining two optimization goals, namely, the smallest robot size reaching a prescribed workspace and the minimum cable tension distributions. A sequence of optimization steps is defined using Genetic algorithms (GAs) applied to LAWEX robot. The proposed objective function is based on a mathematical formulation of the power of a point with respect to bounding surfaces in combination with a performance index to show the distributions of the minimum cable tensions.

关键词： LAWEX robot design bionic robot cable-driven robots optimization power of the point rehabilitation tasks

Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah Hao Wang said El-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

Landsat based distribution mapping of high-altitude peatlands in Hindu Kush Himalayas–a case study of Broghil Valley, Pakistan

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Journal of Mountain Science 2020年第1期17卷 42-49页

作者： Ahmad KHAN Ahmad said Imran ULLAH Department of Geographical Sciences University of MarylandCollege ParkMD20770USA True Green Office 20 Raffaele RoadPlymouthMA 02360USA Departments of Paediatrics and Biochemistry University of TexasSouthwestern Medical CenterDallasTexas 75235USA

In the alpine regions of Hindu Kush,Himalayas and Karakorum, climatic and topographic conditions can support the formation of peat,important for the livelihood of the local communities,and ecological services alike. These peatlands are a source of fuel for the local community, habitat for nesting birds, and water regulation at source for ***-based surveys of high-altitude peatlands are not only difficult, but also expensive and time consuming. Therefore, a method using cost-effective remote sensing technology is required. In this article we assessed the distribution and extent of highaltitude peatlands in a 2000 ha area of Broghil Valley using Landsat 8 data. The composite image was trained using a priori knowledge of the area, and classified into peatland and non-peatland land covers using a supervised decision tree algorithm. The Landsat-based classification map was compared with field data collected with a differential GPS. This comparison suggests 82% overall accuracy, which is fairly high for high altitude areas. The method was successfully applied and has the potential to be replicated for other areas in Pakistan and the highaltitude regions of the neighbouring Asian countries.

关键词： Peatland distribution Chitral Qurumbar Wakhi Hindu Kush Yarkhun

Position Control of Synchronous Motor Drive by Modified Adaptive Two-phase Sliding Mode Controller

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International Journal of Automation and computing 2008年第4期5卷 406-412页

作者： Mohamed said Sayed Ahmed Automation Science and Electrical Engineering School Beijing University of Aeronautics and Astronautics

A modified adaptive two-phase sliding mode controller for the synchronous motor drive that is highly robust to uncertain- ties and external disturbances is proposed in this *** proposed controller uses two-phase sliding mode control (SMC) where the 1st phase mainly controls the system in steady states and disturbed states-it is a smoothing *** 2nd phase is used mainly in the case of disturbed ***,it is an autotuning phase and uses a simple adaptive algorithm to tune the gain of conventional variable structure control (VSC).The modified controller is useful in position control of a permanent magnet synchronous drive.

关键词： Reaching law adaptive control sliding mode control (SMC) chattering.

Non linear modeling of three-dimensional reinforced and fiber concrete structures

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Frontiers of Structural and Civil Engineering 2018年第4期12卷 439-453页

作者： Fatiha IGUETOULENE Youcef BOUAFIA Mohand said KACHI University Mouloud Mammeri of Tizi-Ouzou 15000Algeria

Under the effect of the ascending loading, the behavior of reinforced concrete structures is rather non linear. Research in industry and science aims to extend forward the use of non-linear calculation of fiber concrete for structural parts such as columns, veils and pious, as the fiber concrete is more ductile behavior then the classical concrete behavior. The formulation of the element has been established for modeling the nonlinear behavior of elastic structures in three dimensions, based on the displacement method. For the behavior of concrete and fiber concrete compressive and tensile strength (stress-strain) the uniaxial formulation is used. For steel bi-linear relationship is used. The approach is based on the discretization of the cross section trapezoidal tables. Forming the stiffness matrix of the section, the integral of the surface is calculated as the sum of the integrals on each of the cutting trapezoids. To integrate on the trapeze we have adopted the type of Simpson integration scheme.

关键词： numerical modeling column and beam nonlinear analysis fibers pious reinforcement 3D formulation response load-deflection

Quantitative analysis of cefixime via complexation with palladium(Ⅱ) in pharmaceutical formulations by spectrophotometry

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Journal of Pharmaceutical Analysis 2013年第4期3卷 248-256页

作者： Syed Najmul Hejaz Azmi Bashir Iqbal Nada said Hassan al-Humaimi Iman Rashid Saif al-Salmani Noora ali Saad al-Ghafri Nafisur Rahman Department of Applied Sciences Chemistry SectionHigher College of Technology Department of Chemistry Aligarh Muslim University

An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution （pH 3） in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer＇s law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell＇s sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods.

关键词： Spectrophotometry Cefixime Palladium ion Pd(II)-cefixime complex

Hydrogen Detection With FBG Sensor Technology for Disaster Prevention

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Photonic Sensors 2013年第3期3卷 214-223页

作者： said SAAD Lotfi HASSINE Group of Electronics and Quantum Physics Laboratory of Advanced Materials and Quantum Phenomena Faculty of Sciences of Tunis 2092 Tunisia National Institute of Applied Sciences and Technology University of Carthage North Urban Center of Tunis-B.P.676 Cedex Tunis-1080 Tunisia

Three fiber Bragg grating （FBG） sensors systems for hydrogen detection are presented using the classic Pd （palladium） coating technique （500nm） as the hydrogen sensitive film and titanium （Ti） as the adhesive layer with the etched cladding. These systems are compared and used for disaster environment prevention in hydrogen leakage environment where higher values than the normal are presented which increase the risk of explosion. With these systems, 0. 1% - 4% of the hydrogen volume concentration range in the volume ratio was detected and monitored experimentally in the test room with the very sensitive and stable value which reached 60pm/1% HE. In addition, a fast response time, about 6 s, was obtained with an advanced sensor.

关键词： Fiber Bragg gratin (FBG) hydrogen detection sensor disaster environment prevention Pd coating technique

Application of modified atmosphere packaging using silicone membrane system for shelf life extension of pomegranate (Punica granatum L.) and its effect on physico-chemical properties

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Food Quality and Safety 2019年第3期3卷 145-155页

作者： Shubhangi Srivastava Prashant said Agricultural and Food Engineering Department Indian Institute of TechnologyKharagpurWest BengalIndia College of Agricultural Engineering and Post-Harvest Technology RanipoolSikkimIndia

Objectives:The study was conducted to prolong the shelf life of freshly harvested pomegranate fruits and to find out its physiochemical properties during *** and Methods:Pomegranate fruits of variety‘Bhagawa’were stored in 200,300 gauge high-density polyethylene(HDPE)package,and silicone membrane modified atmospheric storage system at ambient conditions and 10℃.Gas composition inside the package,texture,color,and overall quality parameters were evaluated at these two storage *** physico-chemical properties such as total soluble solids,titratable acidity,ascorbic acid content,total,reducing,and non-reducing sugars,and physiological loss in weight(PLW)were also ***:In ambient storage,the shelf life of pomegranate fruit was 10 days,whereas in modified atmosphere packaging(200 gauge HDPE,300 gauge HDPE,and silicone membrane system),the shelf life of pomegranate fruits was extended up to 60,60,25 days at ambient and 96,96,65 days at 10℃temperature,***:Among the 200,300 gauge HDPE package,and silicone membrane system treatments T1,T5,and T8,respectively,were found better with respect to all the sensory and quality parameters studied.

关键词： silicone membrane shelf life pomegranate temperature ripening