Bibliographies thématiques / Gradient problem of C

Sommaire

Articles de revues
Thèses
Livres
Chapitres de livres
Actes de conférences
Rapports d'organisations

Littérature scientifique sur le sujet « Gradient problem of C »

Auteur : Grafiati

Publié le 4 juin 2021

Mis à jour le 5 février 2022

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « Gradient problem of C ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "Gradient problem of C"

Buczolich. « ANOTHER NOTE ON THE GRADIENT PROBLEM OF C. E. WEIL ». Real Analysis Exchange 22, n^o 2 (1996) : 775. http://dx.doi.org/10.2307/44153954.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Buczolich. « PROGRESS MADE RELATED TO THE GRADIENT PROBLEM OF C. E. WEIL ». Real Analysis Exchange 22, n^o 1 (1996) : 79. http://dx.doi.org/10.2307/44152725.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Liebold, Christian, et Wolfgang H. Müller. « 1D HERMITE ELEMENTS FOR C¹-CONTINUOUS SOLUTIONS IN SECOND GRADIENT ELASTICITY ». Acta Polytechnica CTU Proceedings 7 (9 décembre 2016) : 33–37. http://dx.doi.org/10.14311/app.2017.7.0033.

Texte intégral

Résumé :

We present a modified strain gradient theory of elasticity for linear isotropic materials in order to account for the so-called size effect. Additional material length scale parameters are introduced and the problem of static beam bending is analyzed. A numerical solution is derived by means of a finite element approach. A global C1-continuous displacement field is applied in finite element solutions because the higher-order strain energy density additionally depends on second gradients of displacements. So-called Hermite finite elements are used that allow for merging gradients between elements. The element stiffness matrix as well as the global stiffness matrix of the problem is developed. Convergence, C1-continuity and the size effect in the numerical solution is shown. Experiments on bending stiffnesses of different sized micro beams made of the polymer SU-8 are performed by using an atomic force microscope and the results are compared to the numerical solution.

Styles APA, Harvard, Vancouver, ISO, etc.

Kateb, K. M., K. H. Almitani, K. A. Alnefaie, N. H. Abu-Hamdeh, P. Papadopoulos, H. Askes et E. C. Aifantis. « Application of gradient elasticity to benchmark problems of beam vibrations ». Journal of the Mechanical Behavior of Materials 25, n^o 1-2 (1 avril 2016) : 33–51. http://dx.doi.org/10.1515/jmbm-2016-0001.

Texte intégral

Résumé :

AbstractThe gradient approach, specifically gradient elasticity theory, is adopted to revisit certain typical configurations on mechanical vibrations. New results on size effects and scale-dependent behavior not captured by classical elasticity are derived, aiming at illustrating the usefulness of this approach to applications in advanced technologies. In particular, elastic prismatic straight beams in bending are discussed using two different governing equations: the gradient elasticity bending moment equation (fourth order) and the gradient elasticity deflection equation (sixth order). Different boundary/support conditions are examined. One problem considers the free vibrations of a cantilever beam loaded by an end force. A second problem is concerned with a simply supported beam disturbed by a concentrated force in the middle of the beam. Both problems are solved analytically. Exact free vibration frequencies and mode shapes are derived and presented. The difference between the gradient elasticity solution and its classical counterpart is revealed. The size ratio c/L (c denotes internal length and L is the length of the beam) induces significant effects on vibration frequencies. For both beam configurations, it turns out that as the ratio c/L increases, the vibration frequencies decrease, a fact which implies lower beam stiffness. Numerical examples show this behavior explicitly and recover the classical vibration behavior for vanishing size ratio c/L.

Styles APA, Harvard, Vancouver, ISO, etc.

Sirirut, Taksaporn, et Pattanapong Tianchai. « On Solving of Constrained Convex Minimize Problem Using Gradient Projection Method ». International Journal of Mathematics and Mathematical Sciences 2018 (1 octobre 2018) : 1–10. http://dx.doi.org/10.1155/2018/1580837.

Texte intégral

Résumé :

Let C and Q be closed convex subsets of real Hilbert spaces H1 and H2, respectively, and let g:C→R be a strictly real-valued convex function such that the gradient ∇g is an 1/L-ism with a constant L>0. In this paper, we introduce an iterative scheme using the gradient projection method, based on Mann’s type approximation scheme for solving the constrained convex minimization problem (CCMP), that is, to find a minimizer q∈C of the function g over set C. As an application, it has been shown that the problem (CCMP) reduces to the split feasibility problem (SFP) which is to find q∈C such that Aq∈Q where A:H1→H2 is a linear bounded operator. We suggest and analyze this iterative scheme under some appropriate conditions imposed on the parameters such that another strong convergence theorems for the CCMP and the SFP are obtained. The results presented in this paper improve and extend the main results of Tian and Zhang (2017) and many others. The data availability for the proposed SFP is shown and the example of this problem is also shown through numerical results.

Styles APA, Harvard, Vancouver, ISO, etc.

Jerrard, Robert L., Amir Moradifam et Adrian I. Nachman. « Existence and uniqueness of minimizers of general least gradient problems ». Journal für die reine und angewandte Mathematik (Crelles Journal) 2018, n^o 734 (1 janvier 2018) : 71–97. http://dx.doi.org/10.1515/crelle-2014-0151.

Texte intégral

Résumé :

AbstractMotivated by problems arising in conductivity imaging, we prove existence, uniqueness, and comparison theorems – under certain sharp conditions – for minimizers of the general least gradient problem\inf_{u\in BV_{f}(\Omega)}\int_{\Omega}\varphi(x,Du), wheref:\partial\Omega\to\mathbb{R}is continuous,BV_{f}(\Omega):=\bigl{\{}v\in BV(\Omega):\lim_{r\to 0}\operatornamewithlimits{% ess\,sup}_{y\in\Omega,|x-y|<r}|f(x)-v(y)|=0\text{ for }x\in\partial\Omega\bigr% {\}}and\varphi(x,\xi)is a function that, among other properties, is convex and homogeneous of degree 1 with respect to the ξ variable. In particular, we prove that ifa\in C^{1,1}(\Omega)is bounded away from zero, then minimizers of the weighted least gradient problem\inf_{u\in BV_{f}}\int_{\Omega}a|Du|are unique inBV_{f}(\Omega). We construct counterexamples to show that the regularity assumptiona\in C^{1,1}is sharp, in the sense that it can not be replaced bya\in C^{1,\alpha}(\Omega)with any\alpha<1.

Styles APA, Harvard, Vancouver, ISO, etc.

Kumarasamy, Sakthivel, et Alemdar Hasanov. « An inverse problem for the KdV equation with Neumann boundary measured data ». Journal of Inverse and Ill-posed Problems 26, n^o 1 (1 février 2018) : 133–51. http://dx.doi.org/10.1515/jiip-2017-0038.

Texte intégral

Résumé :

AbstractIn this paper, we consider an inverse coefficient problem for the linearized Korteweg–de Vries (KdV) equation {u_{t}+u_{xxx}+(c(x)u)_{x}=0}, with homogeneous boundary conditions {u(0,t)=u(1,t)=u_{x}(1,t)=0}, when the Neumann data{g(t):=u_{x}(0,t)}, {t\in(0,T)}, is given as an available measured output at the boundary {x=0}. The inverse problem is formulated as a minimum problem for the regularized Tikhonov functional {\mathcal{J}_{\alpha}(c)=\frac{1}{2}\|u_{x}(0,\cdot\,;c)-g\|^{2}_{L^{2}(0,T)}+% \frac{\alpha}{2}\|c^{\prime}\|^{2}_{L^{2}(0,1)}} with Sobolev norm. Based on a priori estimates for the weak and regular weak solutions of the direct and adjoint problems, it is proved that the input-output operator is compact, which shows the ill-posedness of the inverse problem. Then Fréchet differentiability of the Tikhonov functional and Lipschitz continuity of the Fréchet gradient are proved. It is shown that the last result allows us to use an important advantage of gradient methods when the functional is from the class {C^{1,1}(\mathcal{M})}. In the final part, an existence of a solution of the minimum problem for the regularized Tikhonov functional {\mathcal{J}_{\alpha}(c)} is proved.

Styles APA, Harvard, Vancouver, ISO, etc.

Chen, Jinzuo, Mihai Postolache et Yonghong Yao. « S-Subgradient Projection Methods with S-Subdifferential Functions for Nonconvex Split Feasibility Problems ». Symmetry 11, n^o 12 (14 décembre 2019) : 1517. http://dx.doi.org/10.3390/sym11121517.

Texte intégral

Résumé :

In this paper, the original C Q algorithm, the relaxed C Q algorithm, the gradient projection method ( G P M ) algorithm, and the subgradient projection method ( S P M ) algorithm for the convex split feasibility problem are reviewed, and a renewed S P M algorithm with S-subdifferential functions to solve nonconvex split feasibility problems in finite dimensional spaces is suggested. The weak convergence theorem is established.

Styles APA, Harvard, Vancouver, ISO, etc.

Sun, Siyuan, Changchun Yin et Xiuhe Gao. « 3D Gravity Inversion on Unstructured Grids ». Applied Sciences 11, n^o 2 (13 janvier 2021) : 722. http://dx.doi.org/10.3390/app11020722.

Texte intégral

Résumé :

Compared with structured grids, unstructured grids are more flexible to model arbitrarily shaped structures. However, based on unstructured grids, gravity inversion results would be discontinuous and hollow because of cell volume and depth variations. To solve this problem, we first analyzed the gradient of objective function in gradient-based inversion methods, and a new gradient scheme of objective function is developed, which is a derivative with respect to weighted model parameters. The new gradient scheme can more effectively solve the problem with lacking depth resolution than the traditional inversions, and the improvement is not affected by the regularization parameters. Besides, an improved fuzzy c-means clustering combined with spatial constraints is developed to measure property distribution of inverted models in both spatial domain and parameter domain simultaneously. The new inversion method can yield a more internal continuous model, as it encourages cells and their adjacent cells to tend to the same property value. At last, the smooth constraint inversion, the focusing inversion, and the improved fuzzy c-means clustering inversion on unstructured grids are tested on synthetic and measured gravity data to compare and demonstrate the algorithms proposed in this paper.

Styles APA, Harvard, Vancouver, ISO, etc.

Tian, Ming, et Li-Hua Huang. « A General Approximation Method for a Kind of Convex Optimization Problems in Hilbert Spaces ». Journal of Applied Mathematics 2014 (2014) : 1–9. http://dx.doi.org/10.1155/2014/156073.

Texte intégral

Résumé :

The constrained convex minimization problem is to find a pointx∗with the property thatx∗∈C, andh(x∗)=min h(x),∀x∈C, whereCis a nonempty, closed, and convex subset of a real Hilbert spaceH,h(x)is a real-valued convex function, andh(x)is not Fréchet differentiable, but lower semicontinuous. In this paper, we discuss an iterative algorithm which is different from traditional gradient-projection algorithms. We firstly construct a bifunctionF1(x,y)defined asF1(x,y)=h(y)−h(x). And we ensure the equilibrium problem forF1(x,y)equivalent to the above optimization problem. Then we use iterative methods for equilibrium problems to study the above optimization problem. Based on Jung’s method (2011), we propose a general approximation method and prove the strong convergence of our algorithm to a solution of the above optimization problem. In addition, we apply the proposed iterative algorithm for finding a solution of the split feasibility problem and establish the strong convergence theorem. The results of this paper extend and improve some existing results.

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Thèses sur le sujet "Gradient problem of C"

Dagher, Issam J. « Gradient based fuzzy c-means algorithm ». FIU Digital Commons, 1994. http://digitalcommons.fiu.edu/etd/2652.

Texte intégral

Résumé :

A clustering algorithm based on the Fuzzy c-means algorithm (FCM) and the gradient descent method is presented. In the FCM, the minimization process of the objective function is proceeded by solving two equations alternatively in an iterative fashion. Each iteration requires the use of all the data at once. In our proposed approach one datum is presented at a time to the network and the minimization is proceeded using the gradient descent method. Compared to FCM, the experimental results show that our algorithm is very competitive in terms of speed and stability of convergence for large number of data.

Styles APA, Harvard, Vancouver, ISO, etc.

Li, Futong. « Global Optimization Techniques Based on Swarm-intelligent and Gradient-free Algorithms ». Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42307.

Texte intégral

Résumé :

The need for solving nonlinear optimization problems is pervasive in many fields. Particle swarm optimization, advantageous with the simple underlying implementation logic, and simultaneous perturbation stochastic approximation, which is famous for its saving in the computational power with the gradient-free attribute, are two solutions that deserve attention. Many researchers have exploited their merits in widely challenging applications. However, there is a known fact that both of them suffer from a severe drawback, non- effectively converging to the global best solution, because of the local “traps” spreading on the searching space. In this article, we propose two approaches to remedy this issue by combined their advantages. In the first algorithm, the gradient information helps optimize half of the particles at the initialization stage and then further updates the global best position. If the global best position is located in one of the local optima, the searching surface’s additional gradient estimation can help it jump out. The second algorithm expands the implementation of the gradient information to all the particles in the swarm to obtain the optimized personal best position. Both have to obey the rule created for updating the particle(s); that is, the solution found after employing the gradient information to the particle(s) has to perform more optimally. In this work, the experiments include five cases. The three previous methods with a similar theoretical basis and the two basic algorithms take participants in all five. The experimental results prove that the proposed two algorithms effectively improved the basic algorithms and even outperformed the previously designed three algorithms in some scenarios.

Styles APA, Harvard, Vancouver, ISO, etc.

Eklund, Per-Olof. « Psykosociala problem vid hepatit C ». Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26624.

Texte intégral

Résumé :

Vissa sjukdomar för konsekvenser med sig utöver den somatiska bördan. Hepatit C är en av dessa. Detta virus påverkar den drabbades liv på ett sätt som står över den patologiska beskrivningen. Varje år anmäls 2000 fall av hepatit C i Sverige. Syftet med denna litteraturstudie var att få kunskap om omfattningen av psykosociala problem hos hepatit C-smittade. Litteraturstudien grundar sig på sju vetenskapliga artiklar. Forskningsprocessen inspirerades av Goodmans sju olika steg. Som teoretisk referensram har använts Carnevalis modell för ett funktionellt hälsotillstånd i dagligt liv. Resultatet presenteras genom fyra olika teman som identifierades under artikelgranskningen: (1) Stigmatisering av individer med hepatit C, (2) rädsla förknippad med hepatit C, (3) Depressiva symtom förknippade med hepatit C och (4) Bristande socialt stöd vid hepatit. Resultatet pekar på att hepatit C-smittade i stor omfattning upplever psykosociala problem. Detta medför att den smittades livssituation påverkas negativt och därmed minskar dennes möjlighet till att uppleva hälsa.
Certain diseases carry consequences beyond the somatic burden. Hepatitis C is one of them. This virus influences the infected beyond its pathological description. Every year 2000 cases of Hepatitis C are reported in Sweden. The aim of this study was to illuminate the extent and character of psychosocial problems in patients with the diagnosis hepatitis C. The study is based on seven scientific articles. The seven steps for a literature study presented by Goodman inspired the research process. As a theoretical frame of reference Carnevali´s model for a functional and healthy daily life has been used. The analysis resulted in four themes: (1) Stigmatization, (2) fear associated with hepatitis C, (3) depressive symptoms connected with the diagnosis and (4) lack of social support The results indicate that patients with the diagnosis hepatitis C experience psychosocial problems to a larger extent. This also means that these patients are negatively influenced leading to a decreased opportunity to experience health.

Styles APA, Harvard, Vancouver, ISO, etc.

Matthes, H. « Parallel Preconditioners for Plate Problem ». Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800826.

Texte intégral

Résumé :

This paper concerns the solution of plate bending problems in domains composed of rectangles. Domain decomposition (DD) is the basic tool used for both the parallelization of the conjugate gradient method and the construction of efficient parallel preconditioners. A so-called Dirich- let DD preconditioner for systems of linear equations arising from the fi- nite element approximation by non-conforming Adini elements is derived. It is based on the non-overlapping DD, a multilevel preconditioner for the Schur-complement and a fast, almost direct solution method for the Dirichlet problem in rectangular domains based on fast Fourier transform. Making use of Xu's theory of the auxiliary space method we construct an optimal preconditioner for plate problems discretized by conforming Bogner-Fox-Schmidt rectangles. Results of numerical experiments carried out on a multiprocessor sys- tem are given. For the test problems considered the number of iterations is bounded independent of the mesh sizes and independent of the number of subdomains. The resulting parallel preconditioned conjugate gradient method requiresO(h^-2 ln h^-1 ln epsilon^-11) arithmetical operations per processor in order to solve the finite element equations with the relative accuracy epsilon.

Styles APA, Harvard, Vancouver, ISO, etc.

Scipolo, Vittorio. « Scattered neutron tomography based on a neutron transport problem ». Texas A&M University, 2004. http://hdl.handle.net/1969.1/2791.

Texte intégral

Résumé :

Tomography refers to the cross-sectional imaging of an object from either transmission or reflection data collected by illuminating the object from many different directions. Classical tomography fails to reconstruct the optical properties of thick scattering objects because it does not adequately account for the scattering component of the neutron beam intensity exiting the sample. We proposed a new method of computed tomography which employs an inverse problem analysis of both the transmitted and scattered images generated from a beam passing through an optically thick object. This inverse problem makes use of a computationally efficient, two-dimensional forward problem based on neutron transport theory that effectively calculates the detector readings around the edges of an object. The forward problem solution uses a Step-Characteristic (SC) code with known uncollided source per cell, zero boundary flux condition and Sn discretization for the angular dependence. The calculation of the uncollided sources is performed by using an accurate discretization scheme given properties and position of the incoming beam and beam collimator. The detector predictions are obtained considering both the collided and uncollided components of the incoming radiation. The inverse problem is referred as an optimization problem. The function to be minimized, called an objective function, is calculated as the normalized-squared error between predicted and measured data. The predicted data are calculated by assuming a uniform distribution for the optical properties of the object. The objective function depends directly on the optical properties of the object; therefore, by minimizing it, the correct property distribution can be found. The minimization of this multidimensional function is performed with the Polack Ribiere conjugate-gradient technique that makes use of the gradient of the function with respect to the cross sections of the internal cells of the domain. The forward and inverse models have been successfully tested against numerical results obtained with MCNP (Monte Carlo Neutral Particles) showing excellent agreements. The reconstructions of several objects were successful. In the case of a single intrusion, TNTs (Tomography Neutron Transport using Scattering) was always able to detect the intrusion. In the case of the double body object, TNTs was able to reconstruct partially the optical distribution. The most important defect, in terms of gradient, was correctly located and reconstructed. Difficulties were discovered in the location and reconstruction of the second defect. Nevertheless, the results are exceptional considering they were obtained by lightening the object from only one side. The use of multiple beams around the object will significantly improve the capability of TNTs since it increases the number of constraints for the minimization problem.

Styles APA, Harvard, Vancouver, ISO, etc.

Hua, Xiaoqin. « Studies on block coordinate gradient methods for nonlinear optimization problems with separable structure ». 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199447.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Stevenson, George Stuart Michael. « The Women's Liberation Movement and the intractable problem of class, c.1968 - c.1979 ». Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11430/.

Texte intégral

Résumé :

This thesis focuses on the voices, activism and experiences of working-class women engaged with the Women’s Movement between 1968 and 1979. It explores their interactions with feminism and class politics and places particular emphasis on their role in the Women’s Liberation Movement and the productive and reproductive class struggles in the period. This approach defines the WLM as a part of the wider Women’s Movement, alongside women’s industrial and community conflicts. It argues that contemporary accounts seeking to recover the significance of ‘sisterhood’ or prioritise alternative identities in the movement often do so at the expense of its working-class participants and underplay the significance of ‘class’ in the political identities of middle-class liberationists. It asserts therefore that that the integration of working-class women and class politics into the story of the 1970s Women’s Movement requires a reconsideration of the existing narratives of the WLM. In developing this perspective, it extricates the tension between the foundational and ideological importance of class and class politics at individual, regional and national levels of the WLM in Britain on the one hand and the intractable problems that class posed within and around the movement on the other. In so doing, it illustrates how both structural and cultural forms of class analysis can offer complementary insights into women’s identity construction and political consciousness, with particular validity not only for social and political movements but also for the post-war period more widely.

Styles APA, Harvard, Vancouver, ISO, etc.

Marschner, David Emmanuel [Verfasser], et C. [Akademischer Betreuer] Barner-Kowollik. « Wavelength-Orthogonal Approaches Enabling Reprogrammable Gradient Materials / David Emmanuel Marschner ; Betreuer : C. Barner-Kowollik ». Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1196208670/34.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Marschner, David [Verfasser], et C. [Akademischer Betreuer] Barner-Kowollik. « Wavelength-Orthogonal Approaches Enabling Reprogrammable Gradient Materials / David Emmanuel Marschner ; Betreuer : C. Barner-Kowollik ». Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1196208670/34.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Skoglund, Ingegerd. « Algorithms for a Partially Regularized Least Squares Problem ». Licentiate thesis, Linköping : Linköpings universitet, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8784.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Livres sur le sujet "Gradient problem of C"

Savitch, Walter J. Problem solving with C++. 7^e éd. Boston : Pearson/Addison Wesley, 2009.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Keith, Harrow, dir. Problem solving with C. El Granada, CA : Scott/Jones Inc., 1996.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Problem solving with C++. 6^e éd. Boston : Pearson Addison Wesley, 2007.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

C, problem solving and programming. New York : Prentice Hall, 1989.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Engineering problem solving with C. 3^e éd. Upper Saddle River, NJ : Pearson/Prentice Hall, 2005.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Engineering problem solving with C. 4^e éd. Boston : Pearson, 2013.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

J, Gordon Brian, dir. C++ problem solving and programming. New York : Prentice Hall, 1994.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

A, Ingber Jeanine, dir. Engineering problem solving with C++. 3^e éd. Boston : Pearson, 2012.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Dale, Nell B. Programming and problem solving with C++. 3^e éd. Boston : Jones and Bartlett Publishers, 2002.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

B, Koffman Elliot, dir. Problem solving, abstraction & design using C++. 3^e éd. Reading, MA : Addison-Wesley, 2000.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Chapitres de livres sur le sujet "Gradient problem of C"

Papanicolopulos, Stefanos-Aldo, A. Zervos et Ioannis Vardoulakis. « Discretization of Gradient Elasticity Problems Using C 1 Finite Elements ». Dans Advances in Mechanics and Mathematics, 269–77. New York, NY : Springer New York, 2010. http://dx.doi.org/10.1007/978-1-4419-5695-8_28.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Zhang, Yunong, Binbin Qiu et Xiaodong Li. « PDBZ and TDBZ Problem Solving and Comparing ». Dans Zhang-Gradient Control, 229–45. Singapore : Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8257-8_14.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Eymard, Robert, et Pierre Feron. « Gradient Schemes for Stokes Problem ». Dans Finite Volumes for Complex Applications VII-Methods and Theoretical Aspects, 265–73. Cham : Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05684-5_25.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Alnashri, Yahya, et Jerome Droniou. « Gradient Schemes for an Obstacle Problem ». Dans Finite Volumes for Complex Applications VII-Methods and Theoretical Aspects, 67–75. Cham : Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05684-5_5.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Santos, Lisa. « A Diffusion Problem with Gradient Constraint ». Dans Mathematical Models for Phase Change Problems, 389–400. Basel : Birkhäuser Basel, 1989. http://dx.doi.org/10.1007/978-3-0348-9148-6_20.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Merrotsy, Peter. « Middle C ». Dans Pedagogy for Creative Problem Solving, 177–208. New York : Routledge, 2017. : Routledge, 2017. http://dx.doi.org/10.4324/9781315198019-8.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Brockett, Roger W., et Wing Shing Wong. « A Gradient Flow for the Assignment Problem ». Dans New Trends in Systems Theory, 170–77. Boston, MA : Birkhäuser Boston, 1991. http://dx.doi.org/10.1007/978-1-4612-0439-8_20.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Sternberg, Peter, et William P. Ziemer. « The Dirichlet Problem for Functions of Least Gradient ». Dans Degenerate Diffusions, 197–214. New York, NY : Springer New York, 1993. http://dx.doi.org/10.1007/978-1-4612-0885-3_14.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Iacobelli, Mikaela. « A Gradient Flow Perspective on the Quantization Problem ». Dans Springer INdAM Series, 145–65. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-01947-1_7.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Deist, Timo M., Stefanus C. Maree, Tanja Alderliesten et Peter A. N. Bosman. « Multi-objective Optimization by Uncrowded Hypervolume Gradient Ascent ». Dans Parallel Problem Solving from Nature – PPSN XVI, 186–200. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-58115-2_13.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "Gradient problem of C"

Kaloni, P. N., et J. X. Lou. « Electrothermo Convective Instability With Inclined Temperature Gradient ». Dans ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-16357.

Texte intégral

Résumé :

The linear convective stability analysis of a poorly conducting liquid with inclined temperature gradient and under a vertical d. c. electric field is investigated. The liquid is placed between a parallel plate electrode system with the upper electrode heated. The eigenvalue problem is solved by the Chebyshev Tau-QZ method. Consideration is also given to the case when there is no horizontal flow and some interesting results are obtained. For inclined temperature gradient case, it is found that the onset of convection is governed by six parameters RV, RH, Re, Pr, Pe and Se. The effect of varying Re upon critical RV and RH is discussed and some considerations to the occurrence of transverse or longitudinal mode is pointed out.

Styles APA, Harvard, Vancouver, ISO, etc.

Asimopolos, Laurențiu, et Natalia-Silvia Asimopoli. « GEOLOGICAL AND GEOPHYSICAL STUDY FOR ELABORATION OF GEOTHERMAL MODEL IN ORADEA-BAILE FELIX AREA ». Dans GEOLINKS International Conference. SAIMA Consult Ltd, 2020. http://dx.doi.org/10.32008/geolinks2020/b1/v2/12.

Texte intégral

Résumé :

Thermal methods consist of measuring thermal gradient and satellite data, which can be used to determine the Earth's surface temperature and thermal inertia of surficial materials, of thermal infrared radiation emitted at the Earth's surface. Thermal gradient measuring, with a knowledge of the thermal conductivity provides a measure of heat flow. Conditions that may increase or decrease and heat flow are influenced by hydrologic, topographic factors and anomalous thermal conductivity. Also, oxidation of sulphide bodies in-place or on waste deposits, if sufficiently rapid, can generate thermal anomalies, which can provide a measure of the amount of metal being released to the environment. The geothermal gradient on the territory of Romania, the increase of the temperature with the depth, has an average value of 2.5°-3°C/100m, which corresponds to a temperature of 100° C at 3000 m deep. There are many areas where the value of the geothermal gradient differs considerably from this average. For example, in areas where the rock plate suffered rapid dips and the basin was filled with sediment "very young "from a geological point of view, the geothermal gradient may be less than 1° C/100m. On the other hand, in other geothermal areas the gradient exceeds much this average. These areas are true underground thermal reservoirs of potentially high geothermal energy which under certain favourable conditions can be exploited to serve heating installations and domestic hot water systems. The geothermal prospecting for the entire territory of Romania, carried out by temperature measurements allowed the development of geothermal maps, highlighting the temperature distribution at different depths. Geophysical data obtained through various methods and geophysical modelling provide generalized and non-unique solutions to the geometry of underground geological relations as well as to the physical characteristics of different formations. The non-uniqueness of these models (solutions to the direct problem) arises from the impossibility of knowing the boundary conditions between different strata, which together with the propagation equations of the different fields (depending on the geophysical method used for the investigation of the basement) form the systems that offer the solutions of the model

Styles APA, Harvard, Vancouver, ISO, etc.

Li, Shifeng, et Shaochen Chen. « Design and Analysis of a Heat Conduction-Based Continuous Flow Polymerase Chain Reaction System ». Dans ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33548.

Texte intégral

Résumé :

Miniaturized ploymerase chain reaction (PCR) systems have attracted increasing interest in medicine and biology for its reduced sample volume and faster thermal cycling compared to conventional PCR device. The thermal cycling in a PCR device involves three temperatures: 95°C to 90°C for DNA denaturation, 50°C to 65°C for hybridization, and 72°C to 77°C for replication. In this work, a completely new concept of obtaining a temperature zone is presented, i.e., some temperature zone is not created by direct micro-heater heating, by natural heat conduction. Finite element method (FEM) is employed to analyze the temperature distribution in the new PCR designs. Three different designs were compared: (1) three heaters, (2) one heater, and (3) two heaters. For the three-heater design, the FEM simulation shows that large space must be reserved between heaters in order to avoid thermal cross-talking maintain a relatively uniform heating zone. For the single heater design, we have only one heater to reach 92 °C. Due to heat conduction, the temperature reduces gradually along the length of the device. We can setup the hybridization and replication zones at certain locations (along the direction of heat conduction) without using a micro-heater. The PCR device based on this design is easy to fabricate. But FEM simulation shows that the temperature gradient is about 8°C/ram. To overcome this “rapid” temperature gradient problem, we proposed to use two heaters. This design involves two heaters both sides. One heater is controlled to be 92°C for denaturation, and on the other end we use another heater set to 75°C for replication. The hybridization temperature (50 °C ∼ 65°C) is obtained from thermal conduction. In PCR operation, the time ratio for denaturation: hybridization: replication is about 4:4:9. For a continuous flow with a width of 80 μm and a depth of 30 μm and flow ranging from 5 nl/s to 80 nl/s, the 20-cycle PCR can be fabricated within an area of 56 mm × 28 mm area, which is smaller than previous design (Kopp et al., 1998). The length of the microchannel is about 0.6 m, which yields a cycling time from 22 seconds to 6 minutes.

Styles APA, Harvard, Vancouver, ISO, etc.

Laskin, Igor, Boris Volfson et Pavel Redikultsev. « The Study of the Effect of the Hot Box on the Stress-Strain State of the High Temperature Petrochemical Vessels ». Dans ASME 2018 Symposium on Elevated Temperature Application of Materials for Fossil, Nuclear, and Petrochemical Industries. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/etam2018-6733.

Texte intégral

Résumé :

The majority of studies of the heat transfer inside the hot box treats the heat transfer as a steady-state process. This paper demonstrates that this approach cannot be applied to the most dangerous cases of the cyclic thermal stress. The significant thermal gradients may occur in the skirt to shell junction of a high-temperature vessel and set up critical thermal stresses. It is a common practice to use a hot box to equalize temperatures of a shell and a skirt support. Reduction of thermal gradient results from a radiative heat transfer inside this hot box. Where a heating/cooling rate is high enough, as in coke drums, for example, the accounting of transient alters radically the distribution of a thermal stress state, and allows us to reconsider the mechanics of the fracture growth in the skirt to shell weld. This paper proves that during the cooling of coke drums some parts of the skirt support have higher temperatures than the shell, which causes tensile circumferential stresses in the weld. The intensity of the radiative heat transfer falls rapidly, when cooling a shell down to 247 °C, which leads to the increase of thermal gradients in the weld zone. This paper proposes a solution to the thermal problem in 2D, and strain-state analysis — in 3D, due to the presence of skirt slots equally spaced around skirt circumference, which increases the circumferential flexibility. The two-dimensional thermal field has been interpolated to a three-dimensional hexagonal grid for solving the thermo-strength transient problem.

Styles APA, Harvard, Vancouver, ISO, etc.

Grigoriev, M. M., et G. F. Dargush. « A Fast Multi-Level Boundary Element Method for the Steady Heat Diffusion Equation ». Dans ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47450.

Texte intégral

Résumé :

A fast, accurate and efficient multi-level boundary element method is developed to solve general boundary value problems. Here we concentrate on problems of two-dimensional steady potential flow and present a fast direct boundary element formulation. This novel method extends the pioneering work of Brandt and Lubrecht on multi-level multi-integration (MLMI) in several important ways to address problems with mixed boundary conditions. We utilize bi-conjugate gradient methods (BCGM) and implement the MLMI approach for fast matrix and matrix transpose multiplication for every iteration loop. Furthermore, by introducing a C-cycle multigrid algorithm, we find that the number of iterations for the bi-conjugate gradient methods is independent of the boundary element mesh discretization for problems of steady-state heat diffusion considered in this paper. As a result, the computational complexity of the proposed method is proportional to only N · log(N), where N is the number of degrees of freedom.

Styles APA, Harvard, Vancouver, ISO, etc.

Lee, Shang-Hsiu, et Marco J. Castaldi. « High Temperature Corrosion Resistance of Different Commercial Alloys Under Various Corrosive Environments ». Dans 15th Annual North American Waste-to-Energy Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/nawtec15-3220.

Texte intégral

Résumé :

High temperature corrosion is a major operating problem because it results in unscheduled shutdowns in Waste-to-Energy (WTE) plants and accounts for a significant fraction of the total operating cost of WTE plants. Due to the heterogeneous nature of municipal solid waste (MSW) fuel and the presence of aggressive elements such as sulfur and chlorine, WTE plants have higher corrosion rates than coal-fired power plants which operate at higher temperature. To reduce corrosion rates while maximizing the heat recovery efficiency has long been a critical task for WTE operators. Past researchers focused on high temperature corrosion mechanisms and have identified important factors which affect the corrosion rate [1–4]. Also, there have been many laboratory tests seeking to classify the effects of these corrosion factors. However, many tests were performed under isothermal conditions where temperatures of flue gas and metal surface were the same and did not incorporate the synergistic effect of the thermal gradient between environment (flue gas) and metal surface. This paper presents a corrosion resistance test using an apparatus that can maintain a well controlled thermal gradient between the environment and the surface of the metals tested for corrosion resistance. Two commercial substrates (steels SA213-T11 and NSSER-4) were tested under different corrosive environments. The post-test investigation consisted of mass loss measurement of tested coupons, observation of cross-sectional morphology by scanning electron microscopy (SEM), and elemental analysis of corrosion products by energy dispersive spectrometry (EDS). The stainless steel NSSER-4 showed good corrosion resistance within the metal temperature range of 500 °C to 630 °C. The alloy steel SA213-T11 had an acceptable corrosion resistance at metal temperatures up to 540 °C, and the performance decreased dramatically at higher temperatures.

Styles APA, Harvard, Vancouver, ISO, etc.

Pizzolato, Alberto, Adriano Sciacovelli et Vittorio Verda. « Discrete Adjoint Sensitivities for the Real-Time Optimal Control of Large District Heating Networks During Failure Events ». Dans ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66734.

Texte intégral

Résumé :

In this paper, we propose an innovative approach for the real-time optimal control of district heating networks during anomalous conditions. We aim at minimizing the maximum thermal discomfort of the connected users after a pipe breakage by an integrated and centralized management of the user control-valves. Our control strategy uses a gradient-based optimizer driven by discrete adjoint sensitivities, which makes it fast and nearly insensitive to the problem dimensions. We tested the proposed approach by simulating a set of different malfunctions in the Turin District heating network and by analyzing the building temperature field during the optimizer convergence history. Compared to the control strategy in use today, we observe that our approach flattens the temperature field and eliminates discomfort peaks, bringing a considerable increase of the minimum user temperature which ranges from a minimum of 1.8 °C to a maximum of 15.4 °C. Furthermore, our optimization strategy allows for superior results to what is achievable conventionally with an 85 % increase of the pumping head, making back-up pumping devices a non-necessary investment.

Styles APA, Harvard, Vancouver, ISO, etc.

Flet-Berliac, Yannis, et Philippe Preux. « Only Relevant Information Matters : Filtering Out Noisy Samples To Boost RL ». Dans Twenty-Ninth International Joint Conference on Artificial Intelligence and Seventeenth Pacific Rim International Conference on Artificial Intelligence {IJCAI-PRICAI-20}. California : International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/ijcai.2020/376.

Texte intégral

Résumé :

In reinforcement learning, policy gradient algorithms optimize the policy directly and rely on sampling efficiently an environment. Nevertheless, while most sampling procedures are based on direct policy sampling, self-performance measures could be used to improve such sampling prior to each policy update. Following this line of thought, we introduce SAUNA, a method where non-informative transitions are rejected from the gradient update. The level of information is estimated according to the fraction of variance explained by the value function: a measure of the discrepancy between V and the empirical returns. In this work, we use this criterion to select samples that are useful to learn from, and we demonstrate that this selection can significantly improve the performance of policy gradient methods. In this paper: (a) We introduce the SAUNA method to filter transitions. (b) We conduct experiments on a set of benchmark continuous control problems. SAUNA significantly improves performance. (c) We investigate how SAUNA reliably selects samples with the most positive impact on learning and study its improvement on both performance and sample efficiency.

Styles APA, Harvard, Vancouver, ISO, etc.

Zhang, Yanqing, Haoxing Ren, Ben Keller et Brucek Khailany. « Problem C ». Dans ICCAD '20 : IEEE/ACM International Conference on Computer-Aided Design. New York, NY, USA : ACM, 2020. http://dx.doi.org/10.1145/3400302.3415740.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Tonomura, Osamu, Tatsuya Takase, Manabu Kano et Shinji Hasebe. « Optimal Shape Design of Pressure-Driven Microchannels Using Adjoint Variable Method ». Dans ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30109.

Texte intégral

Résumé :

The shape of microchannels is an important design variable to achieve the desired performance. Since most microchannels are, at present, designed by trial and error, a systematic optimal shape design method needs to be established. Computational fluid dynamics (CFD) is often used to rigorously examine the influence of the shape of microchannels on heat and mass transport phenomena in the flow field. However, the rash combination of CFD and the optimization technique based on evaluating gradients of the cost function requires enormous computation time when the number of design variables is large. Recently, the adjoint variable method has attracted the attention as an efficient sensitivity analysis method, particularly for aeronautical shape design, since it allows one to successfully obtain the shape gradient functions independently of the number of design variables. In this research, an automatic shape optimization system based on the adjoint variable method is developed using C language on a Windows platform. To validate the effectiveness of the developed system, pressure drop minimization problems of a 180° curved microchannel and a branched microchannel in incompressible flows under constant volume conditions are solved. These design examples illustrate that the pressure drop of the optimally designed microchannels is decreased by about 20% ∼ 40% as compared with that of the initial shape.

Styles APA, Harvard, Vancouver, ISO, etc.

Rapports d'organisations sur le sujet "Gradient problem of C"

Lewellen, John, et Evgenya Simakov. High gradient C-band research at Los Alamos. Office of Scientific and Technical Information (OSTI), mars 2021. http://dx.doi.org/10.2172/1774375.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Song, Heather, Ari Le et Mark Kirshner. 50 MW C-Band Multiple Beam Klystron (MBK) for High Gradient Accelerators. Office of Scientific and Technical Information (OSTI), août 2019. http://dx.doi.org/10.2172/1557164.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Griffin, J. J. The sharp lepton problem and the C(Q{sub 0}?) scenario. Office of Scientific and Technical Information (OSTI), janvier 1993. http://dx.doi.org/10.2172/10102233.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Gillespie, D. Temperature profile analysis for Amargosa Valley wells LWS-A, ASH-B, and MSH-C. DOE UGTA RI/FS geothermal gradient study results FY 1995. Office of Scientific and Technical Information (OSTI), septembre 1995. http://dx.doi.org/10.2172/125004.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Apostolatos, A., B. Keith, C. Soriano et R. Rossi. D6.1 Deterministic optimization software. Scipedia, 2021. http://dx.doi.org/10.23967/exaqute.2021.2.018.

Texte intégral

Résumé :

This deliverable focuses on the implementation of deterministic optimization algorithms and problem solvers within KRATOS open-source software. One of the main challenges of optimization algorithms in Finite-Element based optimization is how to get the gradient of response functions which are used as objective and constraints when this is not available in an explicit form. The idea is to use local sensitivity analysis to get the gradient of the response function(s)

Styles APA, Harvard, Vancouver, ISO, etc.

Melnyk, Andriy. «INTELLECTUAL DARK WEB» AND PECULIARITIES OF PUBLIC DEBATE IN THE UNITED STATES. Ivan Franko National University of Lviv, mars 2021. http://dx.doi.org/10.30970/vjo.2021.50.11113.

Texte intégral

Résumé :

The article focuses on the «Intellectual Dark Web», an informal group of scholars, publicists, and activists who openly opposed the identity politics, political correctness, and the dominance of leftist ideas in American intellectual life. The author examines the reasons for the emergence of this group, names the main representatives and finds that the existence of «dark intellectuals» is the evidence of important problems in US public discourse. The term «Intellectual Dark Web» was coined by businessman Eric Weinstein to describe those who openly opposed restrictions on freedom of speech by the state or certain groups on the grounds of avoiding discrimination and hate speech. Extensive discussion of the phenomenon of «dark intellectuals» began after the publication of Barry Weiss’s article «Meet the renegades from the «Intellectual Dark Web» in The New York Times in 2018. The author writes of «dark intellectuals» as an informal group of «rebellious thinkers, academic apostates, and media personalities» who felt isolated from traditional channels of communication and therefore built their own alternative platforms to discuss awkward topics that were often taboo in the mainstream media. One of the most prominent members of this group, Canadian clinical psychologist Jordan Peterson, publicly opposed the C-16 Act in September 2016, which the Canadian government aimed to implement initiatives that would prevent discrimination against transgender people. Peterson called it a direct interference with the right to freedom of speech and the introduction of state censorship. Other members of the group had a similar experience that their views were not accepted in the scientific or media sphere. The existence of the «Intellectual Dark Web» indicates the problem of political polarization and the reduction of the ability to find a compromise in the American intellectual sphere and in American society as a whole.

Styles APA, Harvard, Vancouver, ISO, etc.

Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!