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Study of Bacterial Samples Using Laser Induced Breakdown Spectroscopy

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Plasma Science and Technology 2014年第12期16卷 1141-1146页

作者： W A FAROOQ m ATIF W TAWFIK m S ALSALHI Z A ALAHmED m SARFRAZ j P SINGH Physics and Astronomy Department College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia National Institute of Laser and Optronics NiloreIslamabadPakistan National Institute of Laser Enhanced Sciences NILES Department of Environmental ApplicationsCairo UniversityCairoEgypt Sustainable Energy Technologies Centre King Saud UniversityRiyadhSaudi Arabia Institute for Clean Energy Technology Mississippi State UniversityStarkvilleMS 39759USA

Laser-induced breakdown spectroscopy （LIBS） technique has been applied to inves- tigate two different types of bacteria, Escherichia coli （B1） and micrococcus luteus （B2） deposited on glass slides using Spectrolaser 7000. LIBS spectra were analyzed using spectrolaser software. LIBS spectrum of glass substrate was compared with bacteria spectra. Ca, mg, Na, K, P, S, C1, Fe, A1, mn, Cu, C, H and CN-band appeared in bacterial samples in air. Two carbon lines at 193.02 nm, 247.88 nm and one hydrogen line at 656.28 nm with intensity ratios of 1.9, 1.83 and 1.53 appeared in bacterial samples B1 and B2 respectively. Carbon and hydrogen are the important components of the bio-samples like bacteria and other cancer cells. Investigation on LIBS spectra of the samples in He and Ar atmospheres is also presented. Ni lines appeared only in B2 sample in Ar atmosphere. From the present experimental results we are able to show that LIBS technique has a potential in the identification and discrimination of different types of bacteria.

关键词： laser induced breakdown bacteria bio-samples and carbon lines

Overview of SPH-ALE applications for hydraulic turbines in ANDRITZ Hydro

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journal of Hydrodynamics 2018年第1期30卷 114-121页

作者： m.Rentschler j.C.marongiu m.Neuhauser E.Parkinson R&D Department ANDRITZ Hydro

Over the past 13 years, ANDRITZ Hydro has developed an in-house tool based on the SPH-ALE method for applications in flow simulations in hydraulic turbines. The initial motivation is related to the challenging simulation of free surface flows in Pelton turbines, where highly dynamic water jets interact with rotating buckets, creating thin water jets traveling inside the housing and possibly causing disturbances on the runner. The present paper proposes an overview of industrial applications allowed by the developed tool, including design evaluation of Pelton runners and casings, transient operation of Pelton units and free surface flows in hydraulic structures.

关键词： Pelton turbine two-phase folw smoothed particle hydrodynamics(SPH) arbitrary Lagrange-Euler(ALE)

Screw theoretic view on dynamics of spatially compliant beam

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Applied mathematics and mechanics(English Edition) 2010年第9期31卷 1173-1188页

作者：丁希仑 j.m.SELIG Robotics Institute Beijing University of Aeronautics and Astronautics Faculty of Business Computing and Information ManagementLondon South Bank University

Beams with spatial compliance can be deformed as bending in a plane, twisting, and extending. In terms of the screw theory on rigid body motions, the concept of ＂deflection screw＂ is introduced, a spatial compliant beam theory via the deflection screw is proposed, and the spatial compliance of such a beam system is presented and analysed based on the material theory and fundamental kinematic assumptions. To study the dynamics of the spatially compliant beam, the potential energy and the kinetic energy of the beam are discussed by using the screw theory to obtain the Lagrangian. The Rayleigh-Ritz method is used to compute the vibrational frequencies based on discussions of boundary conditions and shape functions. The eigenfrequencies of the beam with spatial compliance are compared with those of individual deformation cases, pure bending, extension, or torsion. Finally, dynamics of a robot with two spatial compliant links and perpendicular joints is studied using the spatial compliant beam theory. Coupling between the joint rigid body motions and the deformations of spatial compliant links can easily be found in dynamic simulation. The study shows the effectiveness of using the screw theory to deal with the problems of dynamic modeling and analysis of mechanisms with spatially compliant links.

关键词： spatial compliance beam deformation dynamics robot

Determination of Time-Dependent Coefficients for a Weakly Degenerate Heat Equation

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Computer modeling in Engineering & Sciences 2020年第5期123卷 475-494页

作者： m.j.Huntul D.Lesnic Department of mathematics Faculty of ScienceJazan UniversityJazanSaudi Arabia Department of Applied mathematics University of LeedsLeedsLS29JTUK

In this paper,we consider solving numerically for the first time inverse problems of determining the time-dependent thermal diffusivity coefficient for a weakly degenerate heat equation,which vanishes at the initial moment of time,and/or the convection coefficient along with the temperature for a one-dimensional parabolic equation,from some additional information about the process(the so-called over-determination conditions).Although uniquely solvable these inverse problems are still ill-posed since small changes in the input data can result in enormous changes in the output *** finite difference method with the Crank-Nicolson scheme combined with the nonlinear Tikhonov regularization are *** resulting minimization problem is computationally solved using the mATLAB toolbox routine *** both exact and noisy input data,accurate and stable numerical results are obtained.

关键词： Inverse problem weakly degenerate heat equation Tikhonov’s regularization

ON THE UNIQUENESS OF THE WEAK SOLUTIONS OF A QUASILINEAR HYPERBOLIC SYSTEm WITH A SINGULAR SOURCE TERm

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Chinese Annals of mathematics,Series B 2002年第3期23卷 317-324页

作者： j.P.DIAS m.FIGUEIRA Dedicated to the memory of jacques-Louis Lions Dedicated to the memory of Jacques-Louis Lions

This paper is a continuation of the authors' previous paper [1]. In this paper the authors prove, assuming additional conditions on the initial data, some results about the existence and uniqueness of the entropy weak... 详细信息

关键词： Cauchy problem Weak solution Quasilinear hyperbolic system

Fourier Analysis with Respect to Bilinear maps

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Acta mathematica Sinica,English Series 2009年第4期25卷 519-530页

作者： O. BLASCO j.m. CALABUIG Department of mathematics Universitat de Valencia Burjassot 46100 Valencia Spain Department of Applied mathematics Universidad Politdcnica de Valencia 46022 Valencia Spain

Several results about convolution and about Fourier coefficients for X-valued functions defined on t he torus satisfying the condition sup ｜｜y｜｜=1∫-π^π｜｜ B （f （e^iθ）, y）｜｜dθ/2π〈 ∞ for a bounded bil... 详细信息

关键词： vector-valued functions Pettis integral Bochner integrals Fourier type

Solvability of the Nonlocal Inverse Parabolic Problem and Numerical Results

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Computer Systems Science & Engineering 2022年第3期40卷 1109-1126页

作者： m.j.Huntul Taki-Eddine Oussaeif Department of mathematics College of ScienceJazan UniversityJazanSaudi Arabia Department of mathematics and Informatics Larbi Ben M’hidi UniversityOum El BouaghiAlgeria

In this paper,we consider the unique solvability of the inverse problem of determining the right-hand side of a parabolic equation whose leading coefficient depends on time variable under nonlocal integral overdetermination *** obtain sufficient conditions for the unique solvability of the inverse *** existence and uniqueness of the solution of the inverse parabolic problem upon the data are established using the fixed point *** inverse problem appears extensively in the modelling of various phenomena in engineering and *** example,seismology,medicine,fusion welding,continuous casting,metallurgy,aircraft,oil and gas production during drilling and operation of *** addition,the numerical solution of the inverse problem is studied by using the Crank-Nicolson finite difference method together with the Tikhonov regularization to find a stable and accurate approximate solution of finite *** resulting nonlinear system of parabolic equation is solved computationally using the mATLAB subroutine *** analytical and numerically simulated noisy input data are *** root mean square error values for various noise levels for both continuous and discontinuous time-dependent heat source term are *** results presented for two examples show the efficiency of the computational method and the accuracy and stability of the numerical solution even in the presence of noise in the input ***,the choice of the regularization parameter is also discussed based on the trial and error technique.

关键词： Inverse problem nonlocal integral condition fixed point theorem Tikhonov regularization nonlinear optimization

ON SOLVABILITY OF A BOUNDARY VALUE PROBLEm FOR THE POISSON EQUATION WITH A NONLOCAL BOUNDARY OPERATOR

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Acta mathematica Scientia 2015年第5期35卷 970-980页

作者： B.j.KADIRKULOV m.KIRANE Tashkent State Institute for Oriental Studies Laboratoire de mathématiques Image et Applications Université de La Rochelle NAAm Research Group Department of Mathematics Faculty of ScienceKing Abdulaziz University

In this work, we investigate the solvability of the boundary value problem for the Poisson equation, involving a generalized Riemann-Liouville and the Caputo derivative of fractional order in the class of smooth functions. The considered problems are generalization of the known Dirichlet and Neumann oroblems with operators of a fractional order.

关键词： operator of fractional integration and differentiation solvability boundary value problem Riemann-Liouville operator Caputo fractional derivative Poisson equation Dirichlet and Neumann problems

Spatial Prediction of Soil Aggregate Stability and Aggregate-Associated Organic Carbon Content at the Catchment Scale Using Geostatistical Techniques

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Pedosphere 2011年第3期21卷 389-399页

作者： j.mOHAmmADI m.H.mOTAGHIAN Department of Soil Science Agriculture CollegeShahrekord University

The association of organic carbon with secondary particles （aggregates） results in its storage and retention in soil. A study was carried out at a catchment covering about 92 km2 to predict spatial variability of soil water-stable aggregates （WSA）, mean weight diameter （mWD） of aggregates and organic carbon （OC） content in macro.- （〉 2 mm）, meso- （1-2 mm）, and micro-aggregate （〈 1 mm） fractions, using geostatistical methods. One hundred and eleven soil samples were eSlleeted at the 0 10cm depth and fractionated into macro-, meso-, and mlcro-aggregates by wet sieving. The OC content was determined for each fraction. A greater percentage of water-stable aggregates was found for micro-aggregates, followed by meso-aggregates. Aggregate OC content was greatest in meso-aggregates （9 g kg-1）, followed by micro-aggregates （7 g kg-1）, while the least OC content was found in macro-aggregates （3 g kg-1）. Although a significant effect （P = 0.000） of aggregate size on aggregate OC content was found, however, our findings did not support the model of aggregate hierarchy. Land use had a significant effect （P = 0.073） on aggregate OC content. The coefficients of variation （CVs） for OC contents associated with each aggregate fraction indicated macro-aggregates as the most variable （CV = 71%）. Among the aggregate fractions, the micro-aggregate fraction had a lower CV value of 27%. macro-aggregates to 84% for micro-aggregates. Geostatistical analysis differences in their spatial patterns in both magnitude and space at variance for most aggregate-associated properties was lower than 45%. The mean content of WSA ranged from 15% for showed that the measured soil variables exhibited each aggregate size fraction. The relative nugget The range value for the variogram of water-stable aggregates was almost similar （about 3 km） for the three studied aggregate size classes. The range value for the variogram of aggregate-associated OC contents ranged from about 3 km for macro-aggregates to about

关键词： kriging organic matter variogram water-stable aggregates