Articles de revues : « Conjugate code »

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YANG, H. L., et W. R. WU. « Low-Complexity Conjugate Gradient Algorithm for Array Code Acquisition ». IEICE Transactions on Communications E90-B, n^o 5 (1 mai 2007) : 1193–200. http://dx.doi.org/10.1093/ietcom/e90-b.5.1193.

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Canli, Eyub, Ali Ates et Sefik Bilir. « Conjugate heat transfer for turbulent flow in a thick walled plain pipe ». EPJ Web of Conferences 180 (2018) : 02014. http://dx.doi.org/10.1051/epjconf/201818002014.

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Laminar and turbulent flow have their own characteristics in respect of heat transfer in pipes. While conjugate heat transfer is a major concern for a thick walled pipe with laminar flow inside it, there are limited studies about a turbulent flow in a thick walled plain pipe considering the conjugate heat transfer. In order to conduct such a work by means of in-house developed code, it was desired to make a preliminary investigation with commercially available CFD codes. ANSYS CFD was selected as the tool since it has a positive reputation in the literature for reliability. Defined heat transfer problem was solved with SIMPLE and Coupled Schemes for pressure velocity coupling and results are presented accordingly.

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Urip, Egel, Ka Heng Liew et S. L. Yang. « Modeling IC Engine Conjugate Heat Transfer Using the KIVA Code ». Numerical Heat Transfer, Part A : Applications 52, n^o 1 (25 juin 2007) : 1–23. http://dx.doi.org/10.1080/10407780601112803.

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Ghanemi, Marzieh, Aminollah Pourshohod, Mohammad Ali Ghaffari, Alireza kheirollah, Mansour Amin, Majid Zeinali et Mostafa Jamalan. « Specific Targeting of HER2-Positive Head and Neck Squamous Cell Carcinoma Line HN5 by Idarubicin-ZHER2 Affibody Conjugate ». Current Cancer Drug Targets 19, n^o 1 (13 décembre 2018) : 65–73. http://dx.doi.org/10.2174/1568009617666170427105417.

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Background:Expression of human epidermal growth factor receptor type 2 (HER2) in head and neck squamous cell carcinoma (HNSCC) cell line HN5 can be employed with great opportunities of success for specific targeting of anti-cancer chemotherapeutic agents.Objective:In the current study, HER2-specific affibody molecule, ZHER2:342 (an engineered protein with great affinity for HER2 receptors) was selected for conjugation to idarubicin (an anti-neoplastic antibiotic).Method:ZHER2:342 affibody gene with one added cysteine code at the its 5′ end was synthesized de novo and then inserted into pET302 plasmid and transferred to E. Coli BL21 hosting system. After induction of protein expression, the recombinant ZHER2 affibody molecules were purified using Ni- NTA resin and purity was analyzed through SDS-PAGE. Affinity-purified affibody molecules were conjugated to idarubicin through a heterobifunctional crosslinker, sulfosuccinimidyl 4-(Nmaleimidomethyl) cyclohexane-1-carboxylate (Sulfo-SMCC). Specific toxicity of idarubicin-ZHER2 affibody conjugate against two HER2-positive cells, HN5 and MCF-7 was assessed through MTT assay after an exposure time of 48 hours with different concentrations of conjugate.Results:Idarubicin in the non-conjugated form showed potent toxic effects against both cell lines, while HN5 cells were significantly more sensitive compared to MCF-7 cells. Dimeric ZHER2 affibody showed a mild decreasing effect on growth of both HN5 and MCF-7 cells at optimum concentration. Idarubicin-ZHER2 affibody conjugate at an optimum concentration reduced viability of HN5 cell line more efficiently compared to MCF-7 cell line.In conclusion, idarubicin-ZHER2 affibody conjugate in optimum concentrations can be used for specific targeting and killing of HN5 cells.

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Khatamifar, Mehdi, Emma Lee Wood, Wen Xian Lin, David Holmes, Steven W. Armfield et Michael P. Kirkpatrick. « A Multigrid Accelerated Code for Simulating Unsteady Conjugate Natural Convection Boundary Layers ». Applied Mechanics and Materials 846 (juillet 2016) : 30–35. http://dx.doi.org/10.4028/www.scientific.net/amm.846.30.

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This paper presents a numerical study on the flow dynamics and heat transfer behaviour of unsteady conjugate natural convection boundary layers (CNCBLs) in a partitioned, air filled square cavity. An unsteady two-dimensional multigrid-assisted solver is developed in the C#.NET programming language on stretched Cartesian meshes. The finite volume method is used to discretise the governing equations. To solve the coupled pressure and velocity, the SIMPLE algorithm is used, and to increase simulation accuracy the Adam-Bashforth, QUICK and central difference schemes are employed for time, convection, and diffusion terms respectively. The Poisson pressure equation is solved through the use of the multigrid method. The developed code is used to model CNCBLs which typically require a large amount of simulation time. The numerical results provide detailed descriptions of unsteady CNCBLs and associated heat transfer behaviour over a wide range of Ra, such as the thermal and viscous boundary layer thicknesses, temperature and velocity distributions, and maximum velocities within the CNCBLs.

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Hoebel, Willi. « Experience with the Incomplete Cholesky Conjugate Gradient Method in a Diffusion Code ». Nuclear Science and Engineering 92, n^o 1 (janvier 1986) : 20–26. http://dx.doi.org/10.13182/nse86-a17860.

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Ahmadi Dastjerdi, Dawoud, et Sanaz Lamei. « Geodesic Flow on the Quotient Space of the Action of ⟨z + 2;−1/z 〉 on the Upper Half Plane ». Analele Universitatii "Ovidius" Constanta - Seria Matematica 20, n^o 3 (1 décembre 2012) : 37–50. http://dx.doi.org/10.2478/v10309-012-0054-z.

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Abstract Let G be the group generated by z ↦ z+2 and z → -1/z , z ∈ ℂ. This group acts on the upper half plane and the associated quotient surface is topologically a sphere with two cusps. Assigning a “geometric” code to an oriented geodesic not going to cusps, with alphabets in ℤ \ {0}, enables us to conjugate the geodesic ow on this surface to a special ow over the symbolic space of these geometric codes. We will show that for k ≥ 1, a subsystem with codes from ℤ \ {0; ±1; ±2;… ; ±k} is a TBS: topologically Bernouli scheme. For similar codes for geodesic ow on modular surface, this was true for k ≥ 3. We also give bounds for the entropy of these subsystems.

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DeTar, Carleton, Steven Gottlieb, Ruizi Li et Doug Toussaint. « MILC Code Performance on High End CPU and GPU Supercomputer Clusters ». EPJ Web of Conferences 175 (2018) : 02009. http://dx.doi.org/10.1051/epjconf/201817502009.

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With recent developments in parallel supercomputing architecture, many core, multi-core, and GPU processors are now commonplace, resulting in more levels of parallelism, memory hierarchy, and programming complexity. It has been necessary to adapt the MILC code to these new processors starting with NVIDIA GPUs, and more recently, the Intel Xeon Phi processors. We report on our efforts to port and optimize our code for the Intel Knights Landing architecture. We consider performance of the MILC code with MPI and OpenMP, and optimizations with QOPQDP and QPhiX. For the latter approach, we concentrate on the staggered conjugate gradient and gauge force. We also consider performance on recent NVIDIA GPUs using the QUDA library.

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LIU, TAILIN, FENGTONG WEN et QIAOYAN WEN. « ON THE AUTOMORPHISM GROUPS OF A FAMILY OF BINARY QUANTUM ERROR-CORRECTING CODES ». International Journal of Quantum Information 04, n^o 06 (décembre 2006) : 1013–22. http://dx.doi.org/10.1142/s0219749906002377.

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Based on the classical binary simplex code [Formula: see text] and any fixed-point-free element f of [Formula: see text], Calderbank et al. constructed a binary quantum error-correcting code [Formula: see text]. They proved that [Formula: see text] has a normal subgroup H, which is a semidirect product group of the centralizer Z(f) of f in GLm(2) with [Formula: see text], and the index [Formula: see text] is the number of elements of Ff = {f, 1 - f, 1/f, 1 - 1/f, 1/(1 - f), f/(1 - f)} that are conjugate to f. In this paper, a theorem to describe the relationship between the quotient group [Formula: see text] and the set Ff is presented, and a way to find the elements of Ff that are conjugate to f is proposed. Then we prove that [Formula: see text] is isomorphic to S3 and H is a semidirect product group of [Formula: see text] with [Formula: see text] in the linear case. Finally, we generalize a result due to Calderbank et al.

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Chomphan. « Thai Speech Coding Based On Conjugate-Structure Algebraic Code Excited Linear Prediction Algorithm ». Journal of Computer Science 7, n^o 1 (1 janvier 2011) : 75–79. http://dx.doi.org/10.3844/jcssp.2011.75.79.

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Saidoune, F., M. N. Bouaziz et A. Aziz. « Conjugate Heat and Mass Transfer on Steady MHD Mixed Convection Flow along a Vertical Slender Hollow Cylinder with Heat Generation and Chemical Reaction Effects ». Defect and Diffusion Forum 406 (janvier 2021) : 53–65. http://dx.doi.org/10.4028/www.scientific.net/ddf.406.53.

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This paper studies the effects of heat generation and chemical reaction on the coupled conjugate heat and mass transfer by MHD laminar mixed convective flow along a vertical slender hollow cylinder. The governing boundary layer equations along with the boundary conditions are first cast into a dimensionless form by a non similar transformation and the resulting equations are then solved by the finite difference method using Matlab@ following the code bvp4c. Numerical results of the velocity, temperature and concentration for different values of the conjugate heat transfer parameter p, the magnetic parameter M, the heat generation Q, and the chemical reaction K are studied. The local skin friction, Nusselt number and Sherwood number are also analyzed and presented graphically. In the numerical ranges of the main parameters, it is found mainly that working with strong conjugate heat transfer or/and all others parameters affects negatively the Nusselt and Sherwood numbers. The same trend is revealed for the skin friction factor.

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Saidoune, F., M. N. Bouaziz et A. Aziz. « Conjugate Heat and Mass Transfer on Steady MHD Mixed Convection Flow along a Vertical Slender Hollow Cylinder with Heat Generation and Chemical Reaction Effects ». Defect and Diffusion Forum 406 (janvier 2021) : 53–65. http://dx.doi.org/10.4028/www.scientific.net/ddf.406.53.

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This paper studies the effects of heat generation and chemical reaction on the coupled conjugate heat and mass transfer by MHD laminar mixed convective flow along a vertical slender hollow cylinder. The governing boundary layer equations along with the boundary conditions are first cast into a dimensionless form by a non similar transformation and the resulting equations are then solved by the finite difference method using Matlab@ following the code bvp4c. Numerical results of the velocity, temperature and concentration for different values of the conjugate heat transfer parameter p, the magnetic parameter M, the heat generation Q, and the chemical reaction K are studied. The local skin friction, Nusselt number and Sherwood number are also analyzed and presented graphically. In the numerical ranges of the main parameters, it is found mainly that working with strong conjugate heat transfer or/and all others parameters affects negatively the Nusselt and Sherwood numbers. The same trend is revealed for the skin friction factor.

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Ferrer, María V., et Salvador Hernández. « Homomorphic Encoders of Profinite Abelian Groups II ». Axioms 11, n^o 4 (29 mars 2022) : 158. http://dx.doi.org/10.3390/axioms11040158.

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Let {Gi:i∈N} be a family of finite Abelian groups. We say that a subgroup G≤∏i∈NGi is order controllable if for every i∈N, there is ni∈N such that for each c∈G, there exists c1∈G satisfying c1|[1,i]=c|[1,i], supp(c1)⊆[1,ni], and order (c1) divides order (c|[1,ni]). In this paper, we investigate the structure of order-controllable group codes. It is proved that if G is an order controllable, shift invariant, group code over a finite abelian group H, then G possesses a finite canonical generating set. Furthermore, our construction also yields that G is algebraically conjugate to a full group shift.

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Schmitt, Christian, Moritz Schmid, Sebastian Kuckuk, Harald Köstler, Jürgen Teich et Frank Hannig. « Reconfigurable Hardware Generation of Multigrid Solvers with Conjugate Gradient Coarse-Grid Solution ». Parallel Processing Letters 28, n^o 04 (décembre 2018) : 1850016. http://dx.doi.org/10.1142/s0129626418500160.

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Not only in the field of high-performance computing (HPC), field programmable gate arrays (FPGAs) are a soaringly popular accelerator technology. However, they use a completely different programming paradigm and tool set compared to central processing units (CPUs) or even graphics processing units (GPUs), adding extra development steps and requiring special knowledge, hindering widespread use in scientific computing. To bridge this programmability gap, domain-specific languages (DSLs) are a popular choice to generate low-level implementations from an abstract algorithm description. In this work, we demonstrate our approach for the generation of numerical solver implementations based on the multigrid method for FPGAs from the same code base that is also used to generate code for CPUs using a hybrid parallelization of MPI and OpenMP. Our approach yields in a hardware design that can compute up to 11 V-cycles per second with an input grid size of 4096[Formula: see text]4096 and solution on the coarsest using the conjugate gradient (CG) method on a mid-range FPGA, beating vectorized, multi-threaded execution on an Intel Xeon processor.

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Basnet, Min Bahadur, Mohammad Anas, Zarghaam Haider Rizvi, Asmer Hamid Ali, Mohammad Zain, Giovanni Cascante et Frank Wuttke. « Enhancement of In-Plane Seismic Full Waveform Inversion with CPU and GPU Parallelization ». Applied Sciences 12, n^o 17 (2 septembre 2022) : 8844. http://dx.doi.org/10.3390/app12178844.

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Full waveform inversion is a widely used technique to estimate the subsurface parameters with the help of seismic measurements on the surface. Due to the amount of data, model size and non-linear iterative procedures, the numerical computation of Full Waveform Inversion are computationally intensive and time-consuming. This paper addresses the parallel computation of seismic full waveform inversion with Graphical Processing Units. Seismic full-waveform inversion of in-plane wave propagation in the finite difference method is presented here. The stress velocity formulation of the wave equation in the time domain is used. A four nodded staggered grid finite-difference method is applied to solve the equation, and the perfectly matched layers are considered to satisfy Sommerfeld’s radiation condition at infinity. The gradient descent method with conjugate gradient method is used for adjoined modelling in full-waveform inversion. The host code is written in C++, and parallel computation codes are written in CUDA C. The computational time and performance gained from CUDA C and OpenMP parallel computation in different hardware are compared to the serial code. The performance improvement is enhanced with increased model dimensions and remains almost constant after a certain threshold. A GPU performance gain of up to 90 times is obtained compared to the serial code.

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Wang, Zhi Jian, Xue Jin Shen et Xiao Yang Chen. « Contact Calculation for Rolling Bearings in Quarter-Spaces ». Key Engineering Materials 642 (avril 2015) : 333–36. http://dx.doi.org/10.4028/www.scientific.net/kem.642.333.

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An elastic contact solution considering the effect of free surface and code are developed using Hetenyi’s approach and semi-analytical method. Discrete convolution-fast Fourier transform (DC-FFT) is used to calculate elastic deformation. The modified conjugate gradient method is applied to solve surface contact pressure. By comparing with other literatures’ results, the program made by authors is proved valid.

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Borisov, Vitaly Evgenyevich, Victor Timofeevich Zhukov, Mikhail Mikhailovich Krasnov, Boris Viktorovich Kritskiy, Natalia Dmitrievna Novikova, Yuri Germanovich Rykov et Olga Borisovna Feodoritova. « Program package NOISEtte-MCFL for simulation multicomponent reacting flows ». Keldysh Institute Preprints, n^o 6 (2023) : 1–23. http://dx.doi.org/10.20948/prepr-2023-6.

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The research software package NOISEtte–MCFL is designed to simulate multicomponent gas dynamic flows taking into account conjugate heat transfer. The NOISEtte–MCFL code is based on the developed original mathematical methodology based on the splitting algorithm for physical processes and an explicit iterative scheme based on Chebyshev polynomials. NOISEtte–MCFL is written in C++ and uses a hybrid three-level parallel structure, including MPI, OpenMP and CUDA technologies. The package is validated and verified on a set of model problems and standard test cases. Comparison with the results of calculations using the commercial ANSYS code and the open source OpenFOAM software is performed.

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Gray, M. D., et M. R. W. Masheder. « Diffuse OH in the Milky Way ». Symposium - International Astronomical Union 206 (2002) : 487–91. http://dx.doi.org/10.1017/s0074180900222912.

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We obtain integrated gains for the OH ground-state lines from an exact radiation transfer code with parameters suitable for a large molecular cloud. Results show that the lines are usually formed in NLTE, and that the satellite lines typically show conjugate behaviour. Constraints are set on the OH abundance and kinetic temperature by the requirement that there be no strong maser emission in the main lines.

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Qiao, Hu, Qingyun Wu, Songlin Yu, Jiang Du et Ying Xiang. « A 3D assembly model retrieval method based on assembly information ». Assembly Automation 39, n^o 4 (2 septembre 2019) : 556–65. http://dx.doi.org/10.1108/aa-03-2018-047.

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Purpose The purpose of this paper is to propose a three-dimensional (3D) assembly model retrieval method based on assembling semantic information to address semantic mismatches, poor accuracy and low efficiency in existing 3D assembly model retrieval methods. Design/methodology/approach The paper proposes an assembly model retrieval method. First, assembly information retrieval is performed, and 3D models that conform to the design intention of the assembly are found by retrieving the code. On this basis, because there are conjugate subgraphs between attributed adjacency graphs (AAG) that have an assembly relationship, the assembly model geometric retrieval is translated into a problem of finding AAGs with a conjugate subgraph. Finally, the frequent subgraph mining method is used to retrieve AAGs with conjugate subgraphs. Findings The method improved the efficiency and accuracy of assembly model retrieval. Practical implications The examples illustrate the specific retrieval process and verify the feasibility and reasonability of the assembly model retrieval method in practical applications. Originality/value The assembly model retrieval method in the paper is an original method. Compared with other methods, good results were obtained.

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De Marinis, Dario, Marco Donato de Tullio, Michele Napolitano et Giuseppe Pascazio. « Improving a conjugate-heat-transfer immersed-boundary method ». International Journal of Numerical Methods for Heat & ; Fluid Flow 26, n^o 3/4 (3 mai 2016) : 1272–88. http://dx.doi.org/10.1108/hff-11-2015-0473.

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Purpose – The purpose of this paper is to provide the current state of the art in the development of a computer code combining an immersed boundary method with a conjugate heat transfer (CHT) approach, including some new findings. In particular, various treatments of the fluid-solid-interface conditions are compared in order to determine the most accurate one. Most importantly, the method is capable of computing a challenging three dimensional compressible turbulent flow past an air cooled turbine vane. Design/methodology/approach – The unsteady Reynolds-averaged Navier–Stokes (URANS) equations are solved within the fluid domain, whereas the heat conduction equation is solved within the solid one, using the same spatial discretization and time-marching scheme. At the interface boundary, the temperatures and heat fluxes within the fluid and the solid are set to be equal using three different approximations. Findings – This work provides an accurate and efficient code for solving three dimensional CHT problems, such as the flow through an air cooled gas turbine cascade, using a coupled immersed boundary (IB) CHT methodology. A one-to-one comparison of three different interface-condition approximations has shown that the two multidimensional ones are slightly superior to the early treatment based on a single direction and that the one based on a least square reconstruction of the solution near the IB minimizes the oscillations caused by the Cartesian grid. This last reconstruction is then used to compute a compressible turbulent flow of industrial interest, namely, that through an air cooled gas turbine cascade. Another interesting finding is that the very promising approach based on wall functions does not combine favourably with the interface conditions for the temperature and the heat flux. Therefore, current and future work aims at developing and testing appropriate temperature wall functions, in order to further improve the accuracy – for a given grid – or the efficiency – for a given accuracy – of the proposed methodology. Originality/value – An accurate and efficient IB CHT method, using a state of the art URANS parallel solver, has been developed and tested. In particular, a detailed study has elucidated the influence of different interface treatments of the fluid-solid boundary upon the accuracy of the computations. Last but not least, the method has been applied with success to solve the well-known CHT problem of compressible turbulent flow past the C3X turbine guide vane.

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Canli, Eyub, Ali Ates et Sefik Bilir. « Comparison of turbulence models and CFD solution options for a plain pipe ». EPJ Web of Conferences 180 (2018) : 02013. http://dx.doi.org/10.1051/epjconf/201818002013.

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Present paper is partly a declaration of state of a currently ongoing PhD work about turbulent flow in a thick walled pipe in order to analyze conjugate heat transfer. An ongoing effort on CFD investigation of this problem using cylindrical coordinates and dimensionless governing equations is identified alongside a literature review. The mentioned PhD work will be conducted using an in-house developed code. However it needs preliminary evaluation by means of commercial codes available in the field. Accordingly ANSYS CFD was utilized in order to evaluate mesh structure needs and asses the turbulence models and solution options in terms of computational power versus difference signification. Present work contains a literature survey, an arrangement of governing equations of the PhD work, CFD essentials of the preliminary analysis and findings about the mesh structure and solution options. Mesh element number was changed between 5,000 and 320,000. k-ϵ, k-ω, Spalart-Allmaras and Viscous-Laminar models were compared. Reynolds number was changed between 1,000 and 50,000. As it may be expected due to the literature, k-ϵ yields more favorable results near the pipe axis and k-ωyields more convenient results near the wall. However k-ϵ is found sufficient to give turbulent structures for a conjugate heat transfer problem in a thick walled plain pipe.

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Wu, Jiasong, Fuzhi Wu, Zhifang Dong, Kaiwen Song, Youyong Kong, Lotfi Senhadji et Huazhong Shu. « Fast Gray Code Kernel Algorithm for the Sliding Conjugate Symmetric Sequency-Ordered Complex Hadamard Transform ». IEEE Access 6 (2018) : 56029–45. http://dx.doi.org/10.1109/access.2018.2871885.

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Chourdakis, Gerasimos, David Schneider et Benjamin Uekermann. « OpenFOAM-preCICE : Coupling OpenFOAM with External Solvers for Multi-Physics Simulations ». OpenFOAM® Journal 3 (27 février 2023) : 1–25. http://dx.doi.org/10.51560/ofj.v3.88.

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Multi-physics simulations, such as conjugate heat transfer or fluid-structure interaction, are often constructed completely in OpenFOAM. However, they can also be formed by coupling OpenFOAM to third-party simulation software via a coupling tool. This approach indirectly adds to the capabilities of OpenFOAM those of other simulation tools (such as physical models or discretization methods more fitting for specific applications), and allows building complex multi-physics simulations by connecting specialized single-physics codes. We present the OpenFOAM-preCICE adapter, a function object that enables standard OpenFOAM solvers to use the open-source, massively parallel coupling library preCICE, without requiring any code modifications. We review alternative coupling approaches, analyze our design decisions, peek into key implementation details, validate the adapter, study the effect on runtime, and give an overview of the growing community of users and contributors.

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Healy, David, et Peter Jupp. « Bimodal or quadrimodal ? Statistical tests for the shape of fault patterns ». Solid Earth 9, n^o 4 (22 août 2018) : 1051–60. http://dx.doi.org/10.5194/se-9-1051-2018.

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Abstract. Natural fault patterns formed in response to a single tectonic event often display significant variation in their orientation distribution. The cause of this variation is the subject of some debate: it could be noise on underlying conjugate (or bimodal) fault patterns or it could be intrinsic signal from an underlying polymodal (e.g. quadrimodal) pattern. In this contribution, we present new statistical tests to assess the probability of a fault pattern having two (bimodal, or conjugate) or four (quadrimodal) underlying modes and orthorhombic symmetry. We use the eigenvalues of the second- and fourth-rank orientation tensors, derived from the direction cosines of the poles to the fault planes, as the basis for our tests. Using a combination of the existing fabric eigenvalue (or modified Flinn) plot and our new tests, we can discriminate reliably between bimodal (conjugate) and quadrimodal fault patterns. We validate our tests using synthetic fault orientation datasets constructed from multimodal Watson distributions and then assess six natural fault datasets from outcrops and earthquake focal plane solutions. We show that five out of six of these natural datasets are probably quadrimodal and orthorhombic. The tests have been implemented in the R language and a link is given to the authors' source code.

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Jo, Jong Chull, Young Hwan Choi et Seok Ki Choi. « Numerical Analysis of Unsteady Conjugate Heat Transfer and Thermal Stress for a Curved Piping System Subjected to Thermal Stratification ». Journal of Pressure Vessel Technology 125, n^o 4 (1 novembre 2003) : 467–74. http://dx.doi.org/10.1115/1.1613947.

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This paper addresses three-dimensional numerical analyses of the unsteady conjugate heat transfer and thermal stress for a PWR pressurizer surge line pipe with a finite wall thickness, subjected to internally thermal stratification. A primary emphasis of the present study is placed on the investigation of the effects of surge flow direction on the determinations of the transient temperature and thermal stress distributions in the pipe wall. In the present numerical analysis, the thermally stratified flows (in-surge flow and out-surge flow) in the pipe line are simulated using the standard κ−ε turbulent model and a simple and convenient numerical method of treating the unsteady conjugate heat transfer on a non-orthogonal coordinate system is developed. The unsteady conjugate heat transfer analysis method is implemented in a finite volume thermal-hydraulic computer code based on a non-staggered grid arrangement, SIMPLEC algorithm and higher-order bounded convection scheme. The finite element method is employed for the thermal stress analysis to calculate non-dimensional stress distributions at the piping wall as a function of time. Some numerical calculations are performed for a PWR pressurizer surge line pipe model with shortened length, subjected to internally thermal stratification caused either by insurge or outsurge flow with a specified velocity, and the results are discussed in detail.

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Tomar, Geetam Singh, et Marcus L. George. « Open-Loop Pitch Analysis for the Conjugate-Structure Algebraic-Code-Excited Linear -Prediction Speech Compression Algorithm ». Asia-pacific Journal of Multimedia services convergent with Art, Humanities, and Sociology 1, n^o 1 (30 juin 2011) : 43–52. http://dx.doi.org/10.14257/ajmscahs.2011.06.03.

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Spokoyny, Ilana, James Y. Chen, Rema Raman, Karin Ernstrom, Kunal Agrawal, Royya F. Modir, Dawn M. Meyer et Brett C. Meyer. « Visual Determination of Conjugate Eye Deviation on Computed Tomography Scan Predicts Diagnosis of Stroke Code Patients ». Journal of Stroke and Cerebrovascular Diseases 25, n^o 12 (décembre 2016) : 2809–13. http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2016.07.039.

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CHITRA, S., et N. KUMARATHARAN. « AN EFFICIENT CFO ESTIMATION AND ICI REDUCTION IN MC-CDMA SYSTEM THROUGH CONJUGATE WEIGHTED MUSIC BASED RPRCC SCHEME ». Latin American Applied Research - An international journal 46, n^o 4 (31 octobre 2016) : 153–59. http://dx.doi.org/10.52292/j.laar.2016.347.

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Multicarrier code division multiple access (MC-CDMA) is one of the most attractive method for future broadband wireless systems and long term evolution (LTE) standard. The performance of MC-CDMA systems is greatly deteriorated by carrier frequency offset (CFO) which is due to oscillator instability and Doppler shifts. CFO leads to loss of orthogonality between the subcarriers and introduces intercarrier interference (ICI). Among the numerous ICI cancellation techniques, the proposed receiver phase rotated conjugate cancellation (RPRCC) offers greater ICI reduction compared to other methods. The distributed nature of networks and concurrent transmission from multiple users in uplink, RPRCC needs multiple frequency offset estimation at the receiver. Multiple signal classification (MUSIC) algorithm is the best suited CFO estimation technique in multiuser environment. However the performance of MUSIC algorithm is inferior for closely spaced CFOs. To achieve precise CFO estimation and greater ICI reduction, RPRCC with conjugate weighted MUSIC based CFO estimation is proposed in this paper. The simulation results depict that the ICI power reduction capability and BER performance of the suggested method outperforms the conventional techniques in both properly and closely spaced CFOs.

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Tomar, Geetam Singh, et Marcus L. George. « Linear Prediction Analysis and Quantization for the Conjugate-Structure Algebraic-Code-Excited Linear-Prediction Speech Compression Algorithm ». Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology 2, n^o 1 (30 juin 2012) : 35–46. http://dx.doi.org/10.14257/ajmscahs.2012.06.01.

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Ghassan Nasif et Yasser El-Okda. « Conjugate Effect on the Thermal Characteristics of Air Impinging Jet ». CFD Letters 13, n^o 10 (1 novembre 2021) : 25–35. http://dx.doi.org/10.37934/cfdl.13.10.2535.

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A computational fluid dynamics (CFD) investigation to determine the conjugate heat transfer (CHT) effect on the stagnation and local thermal characteristics due to an impinging process has been carried out in this study using STAR-CCM+ - Siemens PLM commercial code. The transient Navier-Stokes’s equations are numerically solved using a finite volume approach with k-ω SST eddy viscosity as the turbulence model. A fully developed circular air jet with different Reynolds numbers, impinging vertically onto a heated flat disc with different metals, thicknesses, and boundary heat fluxes are employed in the current study to examine the thermal characteristics and provide an enhanced picture for the convection mechanism that used in jet cooling technology. It is found that the thermal characteristics are influenced by the thermal conductivity and thickness of the target upon using air as a cooling jet. The CHT process enhances the local convective heat transfer at the fluid-solid interface due to the variation in transverse and axial conductive heat transfer inside the metal up to a certain redial extent from the stagnation region compared to the process with no CHT. The extent of the radial enhancement depends on the thermal conductivity of the metal. For a given thermal conductivity, the CHT process acts to increase the temperature and convective heat flux of the stagnation region as the metal thickness increases.

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Li, Hongyang, et Yun Zheng. « Flow-Heat Conjugate Numerical Simulation Based on the Time-Domain Method ». Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 38, n^o 2 (avril 2020) : 261–70. http://dx.doi.org/10.1051/jnwpu/20203820261.

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For the popups of the applicability of the time-domain based unsteady flow-heat coupling numerical simulation method in physical problems with time-period characteristic, the cases of the plate convection heat transfer and the hollow blunt-nosed blade with periodic hot spots were conducted through the internal CFD code namely HGFS. The unsteady results are analysed both in the time——domain and the frequency-domain and the main conclusions are as follows:the numerical simulation results of the plate convection heat transfer indicate that the time-scale of heat convention in the fluid domain is 10-3 s order of magnitude, while that of heat conduction in solid domain is seconds. Thus, the disparity of time scale may lead to a sharp increase in the amount of calculation, and even lead to failure of the calculation method based on time-domain. The unsteady numerical simulation of the simplified turbine blade with hot spots shows that, when the sweep frequency increases to 5 times of the original, the first-order amplitude of the temperature wave in the blade decreases to 50.4%, from 0.343 K to 0.173 K, and the corresponding penetration depth decreases to 42.8%, from 5.21 mm to 2.23 mm. The temperature fluctuation amplitude and penetration depth reduce significantly with the increasing of frequency.

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Jayakumar, B., G. A. Quadir, M. Z. Abdullah et K. N. Seetharamu. « Three Dimensional CFD Conjugate Analysis of Two Inline PLCC Packages Horizontally Mounted ». Journal of Microelectronics and Electronic Packaging 1, n^o 4 (1 octobre 2004) : 244–60. http://dx.doi.org/10.4071/1551-4897-1.4.244.

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A three dimensional conjugate analysis of heat and fluid flow of two 84-pin PLCC packages mounted horizontally on a printed circuit board in a wind tunnel is carried out using a commercial CFD code, FLUENTTM. Various inlet air velocities are used to emulate natural, mixed and forced convection conditions. Some parametric studies are carried out by varying the package chip power, gap between the packages and air inlet velocities. The results are presented in terms of the junction temperature, thermal resistance and top surface average heat transfer coefficient for each package under different operating conditions. The decrease in the junction temperature of the packages with the increase in air inlet velocity is clearly predicted. Further, the leading edge heat transfer coefficient of the packages is always higher than that at the trailing edge for all inlet air velocities considered. It is found that the variation in the package chip power does not influence the average heat transfer coefficient and the thermal resistance of the package at a particular inlet air velocity. Different correlations in terms of the junction temperature as well as the Nusselt number are presented for each package under different convection conditions.

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Beale, S. B. « Conjugate Mass Transfer in Gas Channels and Diffusion Layers of Fuel Cells ». Journal of Fuel Cell Science and Technology 4, n^o 1 (23 mai 2006) : 1–10. http://dx.doi.org/10.1115/1.2393300.

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Prediction of mass transfer effects is a key element in fuel cell design. In this paper, the results of a generalized analysis appropriate to a wide range of designs and flow conditions are presented. Mass transfer in a rectangular gas passage, diffusion layer, and the combination of the two is considered. Fully developed viscous flow is presumed to occur within the passage, while the incompressible form of Darcy’s law is prescribed for the diffusion layer. The mathematical foundations for a simple mass transfer analysis are presented. Detailed calculations are then performed by means of a computational fluid dynamics code. These results are then correlated according to the analytical methodology in terms of nondimensional numbers appropriate to mass transfer analysis; namely, the overall mass transfer driving force as a function of the blowing parameter. Parametric studies are performed for a range of geometries, as characterized by the aspect ratio and blockage factor. It is shown that a simple solution for the overall driving force may readily be obtained from the two individual solutions for the conjugate mass transfer problem. This solution is quite general in its nature, and may readily be used to predict concentration polarization effects for a variety of fuel cells.

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Nebbati, Rabah, et Mahfoud Kadja. « Effect of geometrical and temperature-dependence parameters on forced convection of a nanofluid in a micro-channel heat sink ». World Journal of Engineering 13, n^o 5 (3 octobre 2016) : 399–406. http://dx.doi.org/10.1108/wje-08-2016-0059.

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Purpose The purpose of this study is the numerical prediction of the thermal and hydraulic characteristics (Nusselt number and shear stress) of a forced convection laminar flow through a rectangular micro-channel heat sink, using constant and temperature-dependent thermo-physical properties. The effects of the solids volume fraction and the size of the micro-channel on heat transfer enhancement have also been investigated. Design/methodology/approach The authors use the flow of a water-Al2O3 nanofluid and a single-phase approach. The equations are solved using the commercial code Fluent Version 6.3. This code uses the finite volume approach to solve the equations subject to the boundary conditions, which govern three-dimensional conjugate convection-conduction heat transfer model. The physical domain was meshed using the code GAMBIT. The mesh used is non-uniform and was obtained by sweeping in the Z direction an X-Y surface meshed with QUAD/pave type cells. Findings The results clearly show that the inclusion of nanoparticles produces a considerable increase in the heat transfer. Also, the temperature-dependent models present higher values of local and average Nusselt number than in the case of constant thermo-physical properties, and an increase in the channel dimensions leads to an important increase in heat transfer. Consequently, we ensure a better cooling of the base of the micro-channel heat sink. Research limitations/implications Because of the settling of nanoparticles, the research results may not be generalized to high values of solids volume fraction. Therefore, researchers are encouraged to find other techniques of cooling when the heat loads exceed values that cannot be dissipated using nanonofluids. Practical implications The paper includes implications for the miniaturization of electronic devices such as in microprocessors or those used in robotics and automotive industries, where continually increasing power densities are requiring more innovative techniques of heat dissipation from a small area and small coolant requirements. Originality/value This paper shows the implementation of variable property nanofluid models in CFD commercial codes.

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Hung, Linda, Chen Huang et Emily A. Carter. « Preconditioners and Electron Density Optimization in Orbital-Free Density Functional Theory ». Communications in Computational Physics 12, n^o 1 (juillet 2012) : 135–61. http://dx.doi.org/10.4208/cicp.190111.090911a.

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AbstractOrbital-free density functional theory (OFDFT) is a quantum mechanical method in which the energy of a material depends only on the electron density and ionic positions. We examine some popular algorithms for optimizing the electron density distribution in OFDFT, explaining their suitability, benchmarking their performance, and suggesting some improvements. We start by describing the constrained optimization problem that encompasses electron density optimization. Next, we discuss the line search (including Wolfe conditions) and the nonlinear conjugate gradient and truncated Newton algorithms, as implemented in our open source OFDFT code. We finally focus on preconditioners derived from OFDFT energy functionals. Newly-derived preconditioners are successful for simulation cells of all sizes without regions of low electron-density and for small simulation cells with such regions.

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Bianco, Nicola, Oronzio Manca et Daniele Ricci. « Numerical Model for Multilayer Thin Films Irradiated by a Moving Laser Source ». Defect and Diffusion Forum 283-286 (mars 2009) : 352–57. http://dx.doi.org/10.4028/www.scientific.net/ddf.283-286.352.

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A two-dimensional transient analysis of the conjugate optical-thermal fields induced in a multilayer thin film structure on a glass substrate by a moving Gaussian laser source is carried out numerically. The workpiece is considered semi-infinite along the motion direction and its optical and thermophysical properties are assumed temperature dependent. The COMSOL Multiphysics 3.3 code has been used to solve the combined thermal and electromagnetic problem. The optical field is considered locally one dimensional and Maxwell equations are solved in order to evaluate the absorption in thin film. Results, in terms of transient temperature profiles and fields, are presented for different Peclet numbers and starting point of the heat source with respect to the workpiece boundary along the motion direction.

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Amirante, Dario, Vlad Ganine, Nicholas J. Hills et Paolo Adami. « A Coupling Framework for Multi-Domain Modelling and Multi-Physics Simulations ». Entropy 23, n^o 6 (16 juin 2021) : 758. http://dx.doi.org/10.3390/e23060758.

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This paper describes a coupling framework for parallel execution of different solvers for multi-physics and multi-domain simulations with an arbitrary number of adjacent zones connected by different physical or overlapping interfaces. The coupling architecture is based on the execution of several instances of the same coupling code and relies on the use of smart edges (i.e., separate processes) dedicated to managing the exchange of information between two adjacent regions. The collection of solvers and coupling sessions forms a flexible and modular system, where the data exchange is handled by independent servers that are dedicated to a single interface connecting two solvers’ sessions. Accuracy and performance of the strategy is considered for turbomachinery applications involving Conjugate Heat Transfer (CHT) analysis and Sliding Plane (SP) interfaces.

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Aslan, Nisa, Mustafa Saltan et Bünyamin Demir. « On topological conjugacy of some chaotic dynamical systems on the Sierpinski gasket ». Filomat 35, n^o 7 (2021) : 2317–31. http://dx.doi.org/10.2298/fil2107317a.

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The dynamical systems on the classical fractals can naturally be obtained with the help of their iterated function systems. In the recent years, different ways have been developed to define dynamical systems on the self similar sets. In this paper, we give composition functions by using expanding and folding mappings which generate the classical Sierpinski Gasket via the escape time algorithm. These functions also indicate dynamical systems on this fractal. We express the dynamical systems by using the code representations of the points. Then, we investigate whether these dynamical systems are topologically conjugate (equivalent) or not. Finally, we show that the dynamical systems are chaotic in the sense of Devaney and then we also compute and compare the periodic points.

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Almeida, Ralph Alves Bini da Silva, Grazione De Souza et Helio Pedro Amaral Souto. « Numerical solution of non-isothermal flow in oil reservoirs using OpenACC ». Concilium 23, n^o 2 (13 février 2023) : 666–81. http://dx.doi.org/10.53660/clm-756-23a63.

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In this work, we performed a numerical simulation of the non-isothermal flow in an oil reservoir. Also, we used the OpenACC API to parallelize specific parts of the original code, which allowed the simultaneous execution of different tasks on a NVIDIA GTX 970 G1 video card in a shared memory architecture. The problem was studied using a vertical producer well and static heating wells in a two-dimensional domain. We used the Control Volume Finite Difference (CVFD) method to discretize the governing equations and the Conjugate Gradients method to obtain the solutions (pressure and temperature) of the systems of algebraic equations. As a result, concerning computational performance, a significant reduction in execution time was obtained with the parallelized version.

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Häfner, Dion, René Løwe Jacobsen, Carsten Eden, Mads R. B. Kristensen, Markus Jochum, Roman Nuterman et Brian Vinter. « Veros v0.1 – a fast and versatile ocean simulator in pure Python ». Geoscientific Model Development 11, n^o 8 (16 août 2018) : 3299–312. http://dx.doi.org/10.5194/gmd-11-3299-2018.

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Abstract. A general circulation ocean model is translated from Fortran to Python. Its code structure is optimized to exploit available Python utilities, remove simulation bottlenecks, and comply with modern best practices. Furthermore, support for Bohrium is added, a framework that provides a just-in-time compiler for array operations and that supports parallel execution on both CPU and GPU targets. For applications containing more than a million grid elements, such as a typical 1∘×1∘ horizontal resolution global ocean model, Veros is approximately half as fast as the MPI-parallelized Fortran base code on 24 CPUs and as fast as the Fortran reference when running on a high-end GPU. By replacing the original conjugate gradient stream function solver with a solver from the pyAMG Python package, this particular subroutine outperforms the corresponding Fortran version by up to 1 order of magnitude. The study is concluded with a simple application in which the North Atlantic wave response to a Southern Ocean wind perturbation is investigated. It is found that even in a realistic setting the phase speeds of boundary waves matched the expectations based on theory and idealized models.

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Métivier, Ludovic, et Romain Brossier. « The SEISCOPE optimization toolbox : A large-scale nonlinear optimization library based on reverse communication ». GEOPHYSICS 81, n^o 2 (1 mars 2016) : F1—F15. http://dx.doi.org/10.1190/geo2015-0031.1.

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The SEISCOPE optimization toolbox is a set of FORTRAN 90 routines, which implement first-order methods (steepest-descent and nonlinear conjugate gradient) and second-order methods ([Formula: see text]-BFGS and truncated Newton), for the solution of large-scale nonlinear optimization problems. An efficient line-search strategy ensures the robustness of these implementations. The routines are proposed as black boxes easy to interface with any computational code, where such large-scale minimization problems have to be solved. Traveltime tomography, least-squares migration, or full-waveform inversion are examples of such problems in the context of geophysics. Integrating the toolbox for solving this class of problems presents two advantages. First, it helps to separate the routines depending on the physics of the problem from the ones related to the minimization itself, thanks to the reverse communication protocol. This enhances flexibility in code development and maintenance. Second, it allows us to switch easily between different optimization algorithms. In particular, it reduces the complexity related to the implementation of second-order methods. Because the latter benefit from faster convergence rates compared to first-order methods, significant improvements in terms of computational efforts can be expected.

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Bianco, Nicola, Oronzio Manca et Daniele Ricci. « Numerical Investigation on Transient Conjugate Optical-Thermal Fields in Thin Films Irradiated by Moving Sources for Front Treatments ». Defect and Diffusion Forum 297-301 (avril 2010) : 1439–44. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1439.

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In this paper a numerical analysis on two-dimensional transient of the combined optical-thermal fields caused by a moving Gaussian laser source in a multilayer thin film structure on a glass substrate is carried out. The workpiece is considered semi-infinite along the motion direction and its optical and thermophysical properties are assumed temperature dependent. The COMSOL Multiphysics 3.4 code has been used to solve the combined thermal and electromagnetic problem. In this way, the optical field is considered locally one-dimensional and Maxwell equations are solved in order to evaluate the absorption in thin film. Results, in terms of transient temperature profiles and fields, are presented for different Peclet numbers and thin film thicknesses.

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Toledo, Leonel, Pedro Valero-Lara, Jeffrey S. Vetter et Antonio J. Peña. « Towards Enhancing Coding Productivity for GPU Programming Using Static Graphs ». Electronics 11, n^o 9 (20 avril 2022) : 1307. http://dx.doi.org/10.3390/electronics11091307.

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The main contribution of this work is to increase the coding productivity of GPU programming by using the concept of Static Graphs. GPU capabilities have been increasing significantly in terms of performance and memory capacity. However, there are still some problems in terms of scalability and limitations to the amount of work that a GPU can perform at a time. To minimize the overhead associated with the launch of GPU kernels, as well as to maximize the use of GPU capacity, we have combined the new CUDA Graph API with the CUDA programming model (including CUDA math libraries) and the OpenACC programming model. We use as test cases two different, well-known and widely used problems in HPC and AI: the Conjugate Gradient method and the Particle Swarm Optimization. In the first test case (Conjugate Gradient) we focus on the integration of Static Graphs with CUDA. In this case, we are able to significantly outperform the NVIDIA reference code, reaching an acceleration of up to 11× thanks to a better implementation, which can benefit from the new CUDA Graph capabilities. In the second test case (Particle Swarm Optimization), we complement the OpenACC functionality with the use of CUDA Graph, achieving again accelerations of up to one order of magnitude, with average speedups ranging from 2× to 4×, and performance very close to a reference and optimized CUDA code. Our main target is to achieve a higher coding productivity model for GPU programming by using Static Graphs, which provides, in a very transparent way, a better exploitation of the GPU capacity. The combination of using Static Graphs with two of the current most important GPU programming models (CUDA and OpenACC) is able to reduce considerably the execution time w.r.t. the use of CUDA and OpenACC only, achieving accelerations of up to more than one order of magnitude. Finally, we propose an interface to incorporate the concept of Static Graphs into the OpenACC Specifications.

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Bohn, D. E., et N. Moritz. « Algebraic method for efficient adaption of structured grids to fluctuating geometries ». Proceedings of the Institution of Mechanical Engineers, Part A : Journal of Power and Energy 219, n^o 4 (1 juin 2005) : 303–14. http://dx.doi.org/10.1243/095765005x7619.

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An efficient method for adaption of a structured grid to fluctuating turbine blade geometry is presented based on an algebraic algorithm. The objective of the application of this method is to analyse the aerodynamic, thermal and rotational load of rotating and cooled blades with a conjugate approach. The grid adaption method is validated with two test cases by using a simple deformation model considering the blade as a torsion spring. This model ensures a strong coupling between aerodynamic load and deformation of the blades. Thus, the stability of the numerical code can be analysed. The calculations show that convergence for the blade deformation is reached very soon. Even for great blade deformation the algebraic grid adaption method generates no negative cell volumes although this cannot be guaranteed by an algebraic algorithm.

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Łopata, Stanisław, et Paweł Ocłoń. « The analysis of gradient algorithm effectiveness - two dimensional heat transfer problem ». Archives of Thermodynamics 31, n^o 4 (1 octobre 2010) : 37–50. http://dx.doi.org/10.2478/v10173-010-0026-5.

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The analysis of gradient algorithm effectiveness - two dimensional heat transfer problemThe analysis of effectiveness of the gradient algorithm for the two-dimension steady state heat transfer problems is being performed. The three gradient algorithms - the BCG (biconjugate gradient algorithm), the BICGSTAB (biconjugate gradient stabilized algorithm), and the CGS (conjugate gradient squared algorithm) are implemented in a computer code. Because the first type boundary conditions are imposed, it is possible to compare the results with the analytical solution. Computations are carried out for different numerical grid densities. Therefore it is possible to investigate how the grid density influences the efficiency of the gradient algorithms. The total computational time, residual drop and the iteration time for the gradient algorithms are additionally compared with the performance of the SOR (successive over-relaxation) method.

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Impero Abenavoli, R., M. Carlini, H. Kormanski, K. Rudzinska et A. Sciaboni. « Nondimensional Schmidt Analysis for Optimal Design of Stirling Engines ». Journal of Engineering for Gas Turbines and Power 118, n^o 1 (1 janvier 1996) : 8–14. http://dx.doi.org/10.1115/1.2816555.

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General directions for rough optimal calibration of Stirling machines can be given by a non-dimensional Schmidt model (nDSM). Since different relative parameters and performance indices have been analyzed by nDSM models, there is lack of uniform conclusions in the literature. This paper describes a new nDSM of six parameters and compares four performance indices as functions of relative parameters. Two optimization tasks of two and five parameters are formulated and solved using the nDSM. Maximized criterion is cycle work per unit of mean pressure and total swept volume. An optimization code based on the algorithm of conjugate gradients with projection on linear constraints is described. The optimal values of volume phase angle, nondimensional swept volume, and dead volume are presented for different constraints imposed on temperature ratio and relative dead volumes.

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Ge, Yao, Meng Li, Han Wei, Dong Liang, Xuebin Wang et Yaowei Yu. « Numerical Analysis on Velocity and Temperature of the Fluid in a Blast Furnace Main Trough ». Processes 8, n^o 2 (22 février 2020) : 249. http://dx.doi.org/10.3390/pr8020249.

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The main trough is a part of the blast furnace process for hot metal and molten slag transportation from the tap hole to the torpedo, and mechanical erosion of the trough is an important reason for a short life of a campaign. This article employed OpenFoam code to numerically study and analyze velocity, temperature and wall shear stress of the fluids in the main trough during a full tapping process. In the code, a three-dimensional transient mass, momentum and energy conservation equations, including the standard k-ε turbulence model, were developed for the fluid in the trough. Temperature distribution in refractory is solved by the Fourier equation through conjugate heat transfer with the fluid in the trough. Change velocities of the fluid during the full tapping process are exactly described by a parabolic equation. The investigation results show that there are strong turbulences at the area of hot metal’s falling position and the turbulences have influence on velocity, temperature and wall shear stress of the fluid. With the increase of the angle of the tap hole, the wall shear stress increases. Mechanical erosion of the trough has the smallest value and the campaign of the main trough is estimated to expand over 5 days at the tap hole angle of 7°.

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Khuc, Ngoc-Hang, Ben Tan, Rosalie Tuchscherer, Nigel SB Rawson et Philippe De Wals. « Respiratory Infection and Otitis Media Visits in Relation to Pneumococcal Conjugate Vaccine Use in Saskatchewan ». Canadian Journal of Infectious Diseases and Medical Microbiology 24, n^o 4 (2013) : 179–84. http://dx.doi.org/10.1155/2013/385652.

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BACKGROUND: In Saskatchewan, pneumococcal conjugate vaccination (PCV) was offered to high-risk children in 2002 and to all infants in 2005.OBJECTIVE: To describe trends in the frequency of medical visits for lower respiratory tract infection (LRI) and otitis media (OM) in relation to PCV use during the period 1990 to 2008.METHODS: Statistics regarding the number of children covered by the health insurance plan, PCV administration, and medical visits with a diagnostic code associated with LRI and OM were provided by Saskatchewan Health. Monthly rates were analyzed using dynamic state space models.RESULTS: In all series, there was a marked seasonal cycle and some higher-than-expected winter peak values, possibly associated with epidemics of specific respiratory viruses. Three abrupt decreases in baseline rate were observed for LRI and the final one, in February 2007, could be related to the increased proportion of children vaccinated with PCV. There was no statistical correlation between PCV use and OM visit frequency.CONCLUSION: Many environmental, biological and administrative factors may influence health services use, and an effect of low magnitude of a particular vaccine pertaining to nonspecific outcomes could be obscured in time-series analyses.

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Фалетров, Ярослав Вячеславович, Лилия Игоревна Глинская, Матвей Сергеевич Хорецкий, Ян Владимирович Панада, Нина Степановна Фролова et Владимир Макарович Шкуматов. « Synthesis of triazole-containing ciprofloxacin conjugate and its in silico test as a cytochrome P450 ligand ». Journal of the Belarusian State University. Chemistry, n^o 1 (9 avril 2021) : 21–27. http://dx.doi.org/10.33581/2520-257x-2021-1-21-27.

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Cytochromes P450 are hem-containing monooxygenases which catalyse biosynthesis of many compounds playing an essential role in cellular functions as well as degradation of drugs and xenobiotics. Some P450s (e. g., human CYP19 and CYP17, fungal CYP51) are valid target proteins for some drugs. The others P450s are also interesting for pharmacology-related researches. Aiming to design new fluorescent inhibitor of P450s we have synthesised the azole-bearing conjugate of ciprofloxacin (CPF-bab-Z1). To estimate potential of the compound as a ligand for CYPs we performed high-throughput virtual screening (multiple docking calculations) for CPF-bab-Z1 and multiple known 3D structures of P450s. The best affinity for CPF-bab-Z1 (the smallest value of energy of binding is equal -12.5 kcal/mol) were found for protein with PDB code 5esh among 28 structures of CYP51. The calculated pose of CPF-bab-Z1 in the active site of the protein is characterised by cyclopropyl (but not azole) proximity to the heme iron of the CYP51. The data obtained demonstrate perspectives for in vitro investigations of CPF-bab-Z1 with P450s.

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Nakayama, W., et S. H. Park. « Conjugate Heat Transfer From a Single Surface-Mounted Block to Forced Convective Air Flow in a Channel ». Journal of Heat Transfer 118, n^o 2 (1 mai 1996) : 301–9. http://dx.doi.org/10.1115/1.2825845.

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Conjugate heat transfer from a surface-mounted block (31 × 31 × 7 mm3) to forced convective air flow (1–7 m/s) in a parallel-plate channel was studied experimentally and analytically. Particular attention was directed to the heat flow from the block to the floor through the block support, which was eventually transferred to the air flow over the floor. The concepts of adiabatic wall temperature (Tad) and adiabatic heat transfer coefficient (had) were employed to account for the effect of thermal wake shed from the block on the heat transfer from the floor. The experimental data of Tad and had were used in setting the boundary condition for the numerical analysis of heat conduction in the floor. The accuracy of the numerical predictions of the thermal conductances for different heat flow paths was proven experimentally. The heat conduction analysis code was then used to find the heat transfer capability of various block-support/floor combinations.

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