Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.78544
Baudel Lara Lara, Arturo Fernández Madrigal, Lizbeth Morales Salas, A. Gutiérrez
Applying mechanical perturbations at the working electrode during the electrodeposi- tion process is a novel strategy for materials synthesis that has been used for Cu(In,Ga) Se 2 (CIGS) thin film synthesis. A mechanical perturbations strategy was applied during one-step electrodeposition, and the results are compared with the traditional one-step electrodeposition where no mechanical perturbations were applied. In both cases, a potentiostatic mode was employed, where DC potential is applied to the working electrode with respect to the reference electrode; the potential is regulated by the current at an auxiliary electrode. The CIGS films obtained from both strategies were analyzed as electrodeposited and after being annealed in a selenium atmosphere. The annealed film morphology obtained with the potentiostatic mode plus periodical mechanical perturbations was denser and more compact than the film without mechanical perturbations. Using contour lines, the morphology evolution and mass transport distribution on the working electrode during the electrodeposition process are explained.
在电沉积过程中对工作电极施加机械扰动是一种新的材料合成策略，已被用于Cu(In,Ga) Se 2 (CIGS)薄膜的合成。在一步电沉积过程中应用了机械微扰策略，并将结果与不应用机械微扰的传统一步电沉积进行了比较。在这两种情况下，都采用了恒电位模式，其中直流电位相对于参比电极施加到工作电极;电势由辅助电极上的电流调节。对两种方法制备的CIGS薄膜进行了电沉积和硒气氛退火后的分析。在恒电位模式下加上周期性的机械扰动得到的退火膜比没有机械扰动的膜更致密、更致密。利用等高线解释了电沉积过程中工作电极的形貌演变和质量输运分布。
{"title":"Mechanical Perturbations at the Working Electrode to Materials Synthesis by Electrodeposition","authors":"Baudel Lara Lara, Arturo Fernández Madrigal, Lizbeth Morales Salas, A. Gutiérrez","doi":"10.5772/INTECHOPEN.78544","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.78544","url":null,"abstract":"Applying mechanical perturbations at the working electrode during the electrodeposi- tion process is a novel strategy for materials synthesis that has been used for Cu(In,Ga) Se 2 (CIGS) thin film synthesis. A mechanical perturbations strategy was applied during one-step electrodeposition, and the results are compared with the traditional one-step electrodeposition where no mechanical perturbations were applied. In both cases, a potentiostatic mode was employed, where DC potential is applied to the working electrode with respect to the reference electrode; the potential is regulated by the current at an auxiliary electrode. The CIGS films obtained from both strategies were analyzed as electrodeposited and after being annealed in a selenium atmosphere. The annealed film morphology obtained with the potentiostatic mode plus periodical mechanical perturbations was denser and more compact than the film without mechanical perturbations. Using contour lines, the morphology evolution and mass transport distribution on the working electrode during the electrodeposition process are explained.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128120702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.77147
Yining Shi, Feng Zhang, Jia-Ren Yan, Q. Yu, Jiangnan Li
A new scheme based on perturbation method is presented to solve the problem of solar/ infrared radiative transfer (SRT/IRT) in a scattering medium, in which the inherent optical properties (IOPs) are vertically inhomogeneous. The Eddington approximation for SRTand the two-stream approximation for IRT are used as the zeroth-order solution, and multiple-scattering effect of inhomogeneous IOPs is included in the first-order solution. Observations show that the stratocumulus clouds are vertically inhomogeneous, and the accuracy of SRT/ IRT for stratocumulus clouds by different solutions is evaluated. In the spectral band of 0.25 – 0.69 μ m, the relative error in absorption with inhomogeneous SRT solution is 1.4% at most, but with the homogeneous SRT solution, it can be up to 7.4%. In the spectral band of 5 – 8 μ m, the maximum relative error of downward emissivity can reach (cid:1) 11% for the homogeneous IRTsolution but only (cid:1) 2% for the inhomogeneous IRTsolution.
{"title":"Perturbation Method for Solar/Infrared Radiative Transfer in a Scattering Medium with Vertical Inhomogeneity in Internal Optical Properties","authors":"Yining Shi, Feng Zhang, Jia-Ren Yan, Q. Yu, Jiangnan Li","doi":"10.5772/INTECHOPEN.77147","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.77147","url":null,"abstract":"A new scheme based on perturbation method is presented to solve the problem of solar/ infrared radiative transfer (SRT/IRT) in a scattering medium, in which the inherent optical properties (IOPs) are vertically inhomogeneous. The Eddington approximation for SRTand the two-stream approximation for IRT are used as the zeroth-order solution, and multiple-scattering effect of inhomogeneous IOPs is included in the first-order solution. Observations show that the stratocumulus clouds are vertically inhomogeneous, and the accuracy of SRT/ IRT for stratocumulus clouds by different solutions is evaluated. In the spectral band of 0.25 – 0.69 μ m, the relative error in absorption with inhomogeneous SRT solution is 1.4% at most, but with the homogeneous SRT solution, it can be up to 7.4%. In the spectral band of 5 – 8 μ m, the maximum relative error of downward emissivity can reach (cid:1) 11% for the homogeneous IRTsolution but only (cid:1) 2% for the inhomogeneous IRTsolution.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125270549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.74717
Bo Yang, Tao Yu, H. Shu, Pulin Cao
This chapter develops a sliding-mode perturbation observer-based sliding-mode control (POSMC) scheme for voltage source converter-based high voltage direct current (VSC-HVDC) systems. The combinatorial effect of nonlinearities, parameter uncertainties, unmodeled dynamics, and time-varying external disturbances is aggregated into a perturbation, which is estimated online by a sliding-mode state and perturbation observer (SMSPO). POSMC does not require an accurate VSC-HVDC system model and only the reactive power and DC voltage at the rectifier side while reactive and active powers at the inverter side need to be measured. Additionally, a considerable robustness can be provided through the real-time compensation of the perturbation, in which the upper bound of perturbation is replaced by the real-time estimation of the perturbation, such that the over-conservativeness of conventional sliding-mode control (SMC) can be effectively reduced. Four case studies are carried out on the VSC-HVDC system, such as active and reactive power tracking, AC bus fault, system parameter uncertainties, and weak AC gird connection. Simulation results verify its advantages over vector control and feedback linearization sliding-mode control. Then, a dSPACE-based hardware-in-the-loop (HIL) test is undertaken to validate the implementation feasibility of the proposed approach.
{"title":"Sliding-Mode Perturbation Observer-Based Sliding-Mode Control for VSC-HVDC Systems","authors":"Bo Yang, Tao Yu, H. Shu, Pulin Cao","doi":"10.5772/INTECHOPEN.74717","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.74717","url":null,"abstract":"This chapter develops a sliding-mode perturbation observer-based sliding-mode control (POSMC) scheme for voltage source converter-based high voltage direct current (VSC-HVDC) systems. The combinatorial effect of nonlinearities, parameter uncertainties, unmodeled dynamics, and time-varying external disturbances is aggregated into a perturbation, which is estimated online by a sliding-mode state and perturbation observer (SMSPO). POSMC does not require an accurate VSC-HVDC system model and only the reactive power and DC voltage at the rectifier side while reactive and active powers at the inverter side need to be measured. Additionally, a considerable robustness can be provided through the real-time compensation of the perturbation, in which the upper bound of perturbation is replaced by the real-time estimation of the perturbation, such that the over-conservativeness of conventional sliding-mode control (SMC) can be effectively reduced. Four case studies are carried out on the VSC-HVDC system, such as active and reactive power tracking, AC bus fault, system parameter uncertainties, and weak AC gird connection. Simulation results verify its advantages over vector control and feedback linearization sliding-mode control. Then, a dSPACE-based hardware-in-the-loop (HIL) test is undertaken to validate the implementation feasibility of the proposed approach.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121074627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.77273
H. S. Hoang, R. Baraille
This chapter is devoted to different types of optimal perturbations (OP), deterministic, stochastic, OP in an invariant subspace, and simultaneous stochastic perturbations (SSP). The definitions of OPs are given. It will be shown how the OPs are important for the study on the predictability of behavior of system dynamics, generating ensemble forecasts as well as in the design of a stable filter. A variety of algorithm-based SSP methodology for estimation and decomposition of very high-dimensional (Hd) matrices are presented. Numerical experiments will be presented to illustrate the efficiency and benefice of the perturbation technique.
{"title":"On Optimal and Simultaneous Stochastic Perturbations with Application to Estimation of High-Dimensional Matrix and Data Assimilation in High-Dimensional Systems","authors":"H. S. Hoang, R. Baraille","doi":"10.5772/INTECHOPEN.77273","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.77273","url":null,"abstract":"This chapter is devoted to different types of optimal perturbations (OP), deterministic, stochastic, OP in an invariant subspace, and simultaneous stochastic perturbations (SSP). The definitions of OPs are given. It will be shown how the OPs are important for the study on the predictability of behavior of system dynamics, generating ensemble forecasts as well as in the design of a stable filter. A variety of algorithm-based SSP methodology for estimation and decomposition of very high-dimensional (Hd) matrices are presented. Numerical experiments will be presented to illustrate the efficiency and benefice of the perturbation technique.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127781342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.76827
Kaoru Nakamura, S. Higuchi, Toshiharu Ohnuma
Among the various computational methods in materials science, only first-principles cal- culation based on the density functional theory has predictability for unknown material. Especially, density functional perturbation theory (DFPT) can effectively calculate the second derivative of the total energy with respect to the atomic displacement. By using DFPT method, we can predict piezoelectric constants, dielectric constants, elastic con - stants, and phonon dispersion relationship of any given crystal structure. Recently, we established the computational technique to decompose piezoelectric constants into each atomic contribution, which enable us to gain deeper insights to understand the piezo electricity of material. Therefore, in this chapter, we will introduce the computational framework to predict piezoelectric properties of polar material by means of DFPT and details of decomposition technique of piezoelectric constants. Then, we will show some case studies to predict and discover new piezoelectric material.
{"title":"Density Functional Perturbation Theory to Predict Piezoelectric Properties","authors":"Kaoru Nakamura, S. Higuchi, Toshiharu Ohnuma","doi":"10.5772/INTECHOPEN.76827","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.76827","url":null,"abstract":"Among the various computational methods in materials science, only first-principles cal- culation based on the density functional theory has predictability for unknown material. Especially, density functional perturbation theory (DFPT) can effectively calculate the second derivative of the total energy with respect to the atomic displacement. By using DFPT method, we can predict piezoelectric constants, dielectric constants, elastic con - stants, and phonon dispersion relationship of any given crystal structure. Recently, we established the computational technique to decompose piezoelectric constants into each atomic contribution, which enable us to gain deeper insights to understand the piezo electricity of material. Therefore, in this chapter, we will introduce the computational framework to predict piezoelectric properties of polar material by means of DFPT and details of decomposition technique of piezoelectric constants. Then, we will show some case studies to predict and discover new piezoelectric material.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"49 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132624562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.76828
C. Machado, A. Reynolds
In this work, we apply the method of matched asymptotic expansions to solve the one- dimensional saturation convection-dispersion equation, a nonlinear pseudo-parabolic partial differential equation. This equation is one of the governing equations for two- phase flow in a porous media when including capillary pressure effects, for the specific initial and boundary conditions arising when injecting water in an infinite radial piece- wise homogeneous horizontal medium containing oil and water. The method of matched asymptotic expansions combines inner and outer expansions to construct the global solu- tion. In here, the outer expansion corresponds to the solution of the nonlinear first-order hyperbolic equation obtained when the dispersion effects driven by capillary pressure became negligible. This equation has a monotonic flux function with an inflection point, and its weak solution can be found by applying the method of characteristics. The inner expansion corresponds to the shock layer, which is modeled as a traveling wave obtained by a stretching transformation of the partial differential equation. In the transformed domain, the traveling wave solution is solved using regular perturbation theory. By combining the solution for saturation with the so-called Thompson-Reynolds steady-state theory for obtaining the pressure, one can obtain an approximate analytical solution for the wellbore pressure, which can be used as the forward solution which analyzes pressure data by pressure-transient analysis.
{"title":"Application of the Method of Matched Asymptotic Expansions to Solve a Nonlinear Pseudo-Parabolic Equation: The Saturation Convection-Dispersion Equation","authors":"C. Machado, A. Reynolds","doi":"10.5772/INTECHOPEN.76828","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.76828","url":null,"abstract":"In this work, we apply the method of matched asymptotic expansions to solve the one- dimensional saturation convection-dispersion equation, a nonlinear pseudo-parabolic partial differential equation. This equation is one of the governing equations for two- phase flow in a porous media when including capillary pressure effects, for the specific initial and boundary conditions arising when injecting water in an infinite radial piece- wise homogeneous horizontal medium containing oil and water. The method of matched asymptotic expansions combines inner and outer expansions to construct the global solu- tion. In here, the outer expansion corresponds to the solution of the nonlinear first-order hyperbolic equation obtained when the dispersion effects driven by capillary pressure became negligible. This equation has a monotonic flux function with an inflection point, and its weak solution can be found by applying the method of characteristics. The inner expansion corresponds to the shock layer, which is modeled as a traveling wave obtained by a stretching transformation of the partial differential equation. In the transformed domain, the traveling wave solution is solved using regular perturbation theory. By combining the solution for saturation with the so-called Thompson-Reynolds steady-state theory for obtaining the pressure, one can obtain an approximate analytical solution for the wellbore pressure, which can be used as the forward solution which analyzes pressure data by pressure-transient analysis.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130906584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.79022
S. Bahri
In this chapter, we introduce a multiplication operation that allows us to give to the Carleman integral operator of second class the form of a multiplication operator. Also we establish the formal theory of perturbation of such operators.
{"title":"A Formal Perturbation Theory of Carleman Operators","authors":"S. Bahri","doi":"10.5772/INTECHOPEN.79022","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.79022","url":null,"abstract":"In this chapter, we introduce a multiplication operation that allows us to give to the Carleman integral operator of second class the form of a multiplication operator. Also we establish the formal theory of perturbation of such operators.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124136278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-17DOI: 10.5772/INTECHOPEN.79513
A. Morozov
We are not going to present the classical results on linear parametric systems, since they are widely discussed in literature. Instead, we shall consider nonlinear parametric systems and discuss the conditions of new motion existence in the resonance zones: the regular ones (on an invariant torus) and the irregular ones (on a quasi-attractor). On the basis of the self-oscillatory shortened system which determines the topology of resonance zones, we study the transition from a resonance to a non-resonance case under a change of the detuning. We then apply our results to some concrete examples. It is interesting to study the behavior of a parametric system when the ring-like resonance zone is contracted into a point, i.e., to describe the bifurcations which occur in the course of transition from the plain nonlinear resonance to the parametric one. We are based on article, and we follow a material from the book.
{"title":"Periodic Perturbations: Parametric Systems","authors":"A. Morozov","doi":"10.5772/INTECHOPEN.79513","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.79513","url":null,"abstract":"We are not going to present the classical results on linear parametric systems, since they are widely discussed in literature. Instead, we shall consider nonlinear parametric systems and discuss the conditions of new motion existence in the resonance zones: the regular ones (on an invariant torus) and the irregular ones (on a quasi-attractor). On the basis of the self-oscillatory shortened system which determines the topology of resonance zones, we study the transition from a resonance to a non-resonance case under a change of the detuning. We then apply our results to some concrete examples. It is interesting to study the behavior of a parametric system when the ring-like resonance zone is contracted into a point, i.e., to describe the bifurcations which occur in the course of transition from the plain nonlinear resonance to the parametric one. We are based on article, and we follow a material from the book.","PeriodicalId":114469,"journal":{"name":"Perturbation Methods with Applications in Science and Engineering","volume":"37 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131609102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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