Academic literature on the topic '1D code'
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Journal articles on the topic "1D code"
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Matem, Rima, S. A. Aljunid, M. N Junita, C. B. M Rashidi, and Israa Shihab Aqrab. "Enhancement of optical code division multiple access system based on 2D ZCC/MD spectral/spatial code." Indonesian Journal of Electrical Engineering and Computer Science 14, no. 2 (May 1, 2019): 661. http://dx.doi.org/10.11591/ijeecs.v14.i2.pp661-667.
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<span>The combination of 1D zero cross correlation (ZCC) and 1D Multi Diagonal (MD) results a new two dimensional hybrid called 2D ZCC/MD code for spectral/spatial OCDMA system. The proposed code aims to enhance the functional qualities of Optical Code Division Multiple Access (OCDMA) and to overcome the limitations of one dimensional codes. In this paper, 2D ZCC/MD is evaluated at data rate; 622Mbps. A comparison of the proposed 2D ZCC/MD code to 1D Random Diagonal (RD) and 1D Modified Double Weight (MDW) highlight that 2D ZCC/MD can support a large number of active users even at the higher user bit rate. Furthermore, in term of effective power 2D ZCC/MD can achieve lower effective power.</span>
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Matem, Rima, S. A. Aljunid, M. N. Junita, C. B. M. Rashidi, and Israa Shihab Aqrab. "Performance analysis of spectral/spatial of OCDMA system using 2D hybrid ZCC/MD code." Indonesian Journal of Electrical Engineering and Computer Science 13, no. 2 (February 1, 2019): 569. http://dx.doi.org/10.11591/ijeecs.v13.i2.pp569-574.
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This paper proposes a new spectral/spatial code for Spectral Amplitude Coding in Optical Coding Division Multiple Access (SAC-OCDMA) called two-Dimensional hybrid ZCC/MD code. The new code combines two of the one –dimensional codes which are Zero Cross Correlation (1D ZCC) and Multi-Diagonal code (1D MD). Moreover, it produces a zero cross correlation property for each code. The main goal of this proposed code is to mitigate Phase Induced Intensity Noise and eliminate Multiple Access Interference (MAI). This proposed code can provide a better performance comparing to other codes as 2D FCC/MDW and 2D DPDC according to the obtained numerical analysis.
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WANG, KONGQIAO, YANMING ZOU, and HAO WANG. "1D BAR CODE READING ON CAMERA PHONES." International Journal of Image and Graphics 07, no. 03 (July 2007): 529–50. http://dx.doi.org/10.1142/s0219467807002805.
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The availability of camera phones provides people with a mobile platform for decoding bar codes, whereas conventional scanners lack mobility. However, using a normal camera phone in such applications is challenging due to the out-of-focus problem. In this paper, we present the research effort on the bar code reading algorithms using a VGA camera phone, NOKIA 7650. EAN-13, a widely used 1D bar code standard, is taken as an example to show the efficiency of the method. A wavelet-based bar code region location and knowledge-based bar code segmentation scheme is applied to extract bar code characters from poor-quality images. All the segmented bar code characters are input to the recognition engine, and based on the recognition distance, the bar code character string with the smallest total distance is output as the final recognition result of the bar code. In order to train an efficient recognition engine, the modified Generalized Learning Vector Quantization (GLVQ) method is designed for optimizing a feature extraction matrix and the class reference vectors. 19 584 samples segmented from more than 1000 bar code images captured by NOKIA 7650 are involved in the training process. Testing on 292 bar code images taken by the same phone, the correct recognition rate of the entire bar code set reaches 85.62%. We are confident that auto focus or macro modes on camera phones will bring the presented method into real world mobile use.
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Yeh, Bih-Chyun. "Noncoherent Spectral Optical CDMA System Using 1D Active Weight Two-Code Keying Codes." Mathematical Problems in Engineering 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/3724843.
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We propose a new family of one-dimensional (1D) active weight two-code keying (TCK) in spectral amplitude coding (SAC) optical code division multiple access (OCDMA) networks. We use encoding and decoding transfer functions to operate the 1D active weight TCK. The proposed structure includes an optical line terminal (OLT) and optical network units (ONUs) to produce the encoding and decoding codes of the proposed OLT and ONUs, respectively. The proposed ONU uses the modified cross-correlation to remove interferences from other simultaneous users, that is, the multiuser interference (MUI). When the phase-induced intensity noise (PIIN) is the most important noise, the modified cross-correlation suppresses the PIIN. In the numerical results, we find that the bit error rate (BER) for the proposed system using the 1D active weight TCK codes outperforms that for two other systems using the 1D M-Seq codes and 1D balanced incomplete block design (BIBD) codes. The effective source power for the proposed system can achieve −10 dBm, which has less power than that for the other systems.
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Sécher, Matthieu, Philippe Ung, Eric Valette, Magali Jodeau, and Nicole Goutal. "COURLIS: a 1D suspension and bedload code." E3S Web of Conferences 40 (2018): 05038. http://dx.doi.org/10.1051/e3sconf/20184005038.
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COURLIS is a 1D sedimentology module coupled with MASCARET, 1D hydraulic code of the TELEMAC-MASCARET open source system. The code has been developed for more than 10 years, mainly for suspension sediment transport. Recently, the need of a 1D bedload code has been identified to model the long term evolution of rivers and reservoirs (several decades). New numerical schemes were implemented, some improvements were done in the geometry evolution algorithms. In terms of performance and robustness, the best scheme implemented is a finite volume upwind/downwind scheme. Several solutions are implemented to reduce calculation time. This new version of COURLIS for bedload transport was validated successfully on test-cases (Soni and Newton experiments). A real case has been simulated during an 11 year period. The calculation time is very similar to those obtained with codes tested in the benchmark and the results are in a good agreement with measurements and other code results. COURLIS (suspension and bedload transport) will be released in the next version of the TELEMAC-MASCARET open source system and so, it will be freely available for sedimentology community. Further developments are planned in 2018.
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Sharma, Teena, Abdellah Chehri, Paul Fortier, Hassan Yousif Ahmed, Medien Zeghid, and Waqas A. Imtiaz. "Optical Code Construction of 2D Spectral/Spatial BIBD Codes for SAC-OCDMA Systems." Applied Sciences 11, no. 2 (January 15, 2021): 783. http://dx.doi.org/10.3390/app11020783.
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Optical code division multiple access (OCDMA) shows limitations in terms of the inefficient bandwidth utilization and low spectral density with one-dimensional (1D) codes. To overcome these limitations, a novel design is presented using a two dimensional (2D) spectral/spatial multiwavelength coding scheme. The proposed code is constructed using a 1D balanced incomplete block design (BIBD) technique. Theoretical and analytical results indicate that the proposed code provided improvement in the number of simultaneous users, code construction, and cross-correlation and minimized noise. Moreover, the bandwidth requirements can be minimized, and it can provide flexibility in addressing code sequences. Finally, results were compared with existing spectral-spatial 2D codes such as diagonal eigenvalue unity (DEU) and 2D diluted perfect difference (DPD). It was observed that the 2D-BIBD code fulfilled optical transmission needs with minimum effective source power (Psr = −27.5 dBm) when compared to 2D-DEU (−26.5 dBm) and 2D-DPD (−25.5 dBm) codes. Overall, our results suggested that the performance of BER for the proposed code was 72% and 22% higher than the existing 2D-DPD and 2D-DEU codes, respectively.
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Vidal, Jean-Philippe, Sabine Moisan, Jean-Baptiste Faure, and Denis Dartus. "Towards a reasoned 1D river model calibration." Journal of Hydroinformatics 7, no. 2 (March 1, 2005): 91–104. http://dx.doi.org/10.2166/hydro.2005.0009.
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Model calibration remains a critical step in numerical modelling. After many attempts to automate this task in water-related domains, questions about the actual need for calibrating physics-based models are still open. This paper proposes a framework for good model calibration practice for end-users of 1D hydraulic simulation codes. This framework includes a formalisation of objects used in 1D river hydraulics along with a generic conceptual description of the model calibration process. It was implemented within a knowledge-based system integrating a simulation code and expert knowledge about model calibration. A prototype calibration support system was then built up with a specific simulation code solving subcritical unsteady flow equations for fixed-bed rivers. The framework for model calibration is composed of three independent levels related, respectively, to the generic task, to the application domain and to the simulation code itself. The first two knowledge levels can thus easily be reused to build calibration support systems for other application domains, like 2D hydrodynamics or physics-based rainfall–runoff modelling.
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Yen, Chih-Ta, and Chih-Ming Chen. "BER Analysis Using Beat Probability Method of 3D Optical CDMA Networks with Double Balanced Detection." Mathematical Problems in Engineering 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/456829.
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This study proposes novel three-dimensional (3D) matrices of wavelength/time/spatial code for code-division multiple-access (OCDMA) networks, with a double balanced detection mechanism. We construct 3D carrier-hopping prime/modified prime (CHP/MP) codes by extending a two-dimensional (2D) CHP code integrated with a one-dimensional (1D) MP code. The corresponding coder/decoder pairs were based on fiber Bragg gratings (FBGs) and tunable optical delay lines integrated with splitters/combiners. System performance was enhanced by the low cross correlation properties of the 3D code designed to avoid the beat noise phenomenon. The CHP/MP code cardinality increased significantly compared to the CHP code under the same bit error rate (BER). The results indicate that the 3D code method can enhance system performance because both the beating terms and multiple-access interference (MAI) were reduced by the double balanced detection mechanism. Additionally, the optical component can also be relaxed for high transmission scenery.
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Balaž, Antun, Ivana Vidanović, Danica Stojiljković, Dušan Vudragović, Aleksandar Belić, and Aleksandar Bogojević. "SPEEDUP Code for Calculation of Transition Amplitudes via the Effective Action Approach." Communications in Computational Physics 11, no. 3 (March 2012): 739–55. http://dx.doi.org/10.4208/cicp.131210.180411a.
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AbstractWe present Path Integral Monte Carlo C code for calculation of quantum mechanical transition amplitudes for 1D models. The SPEEDUP C code is based on the use of higher-order short-time effective actions and implemented to the maximal order p=18 in the time of propagation (Monte Carlo time step), which substantially improves the convergence of discretized amplitudes to their exact continuum values. Symbolic derivation of higher-order effective actions is implemented in SPEEDUP Mathematica codes, using the recursive Schrödinger equation approach. In addition to the general 1D quantum theory, developed Mathematica codes are capable of calculating effective actions for specific models, for general 2D and 3D potentials, as well as for a general many-body theory in arbitrary number of spatial dimensions.
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Gupta, Sumit, and Aditya Goel. "Design of Multiservice Code (MS) in Spectral/Temporal/Spatial Domain for OCDMA System." Journal of Optical Communications 41, no. 3 (April 28, 2020): 305–17. http://dx.doi.org/10.1515/joc-2017-0180.
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AbstractThis paper explores the design of multiservice code (MS) in spectral, time spreading and wavelength domains (3-Dimensional). The proposed 3D code is designed in such a manner that follows the ideal in phase unit cross correlation in spectral, time spreading and wavelength domains. The proposed encoder generates the MS code effectively in 3D domain and decoder suppresses the multi-user interferences successfully. Performance analyses are carried out by considering the all noises such as phase induce intensity noise(PIIN), shot noise and thermal noise. The analysis of 3D-MS code for variable code length is also performed for measurement of variation in bit error rate against the received power and number of active users in the design. The observed performances are also compared with existing codes such as 2D-MDW, 3D-PDC and 1D-MS code and the proposed code shows the better performance. The analysis of bit error rate of proposed code is carried out against the number of users at 0.622Gbits/s data rate and 0 dBm received power and comparison is also formed with the existing code such as 3D PD(M=21, N=3, P=3), 2DMDW(M=63, P=3), PDC(M=57, P=3) and 1D MS Code. It is noted that 3D MS code shows the better performance than the existing methods. Analysis is also evaluated for variable weight and variable length codes in order to observe the variation in bit error rate with variation in received power and number of simultaneous users.
Dissertations / Theses on the topic "1D code"
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Santo, Luca. "AA-CAES physical modelling: integration of a 1D TES code and plant performance analysis." Thesis, Uppsala universitet, Tillämpad kärnfysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-360448.
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The focus of this thesis work was the development of an approachto couple a previosly existing Thermal Energy Storage (TES) modelwritten in C++ with a Simulink/Simscape plant model to simulate anAdvanced Adiabatic Compressed Air Energy Storage (AA-CAES) plant.After the creation and validation of such tool, the complete modelwas used to run simulations, with the aim of assessing the AA-CAESplant's performance under multiple patterns of charge anddischarge.Most of the works found in the literature only provide values ofstorage efficiency obtained from analytical approaches, whilethose that use simulation tools provide average values ofefficiencies when the plant is performing a series of identicalcycles of charge and discharge. During this thesis project,instead, simulations were performed for consecutive irregularcycles determined as the plant response to the electric grid powerrequest. The average efficiency values obtained provide thereforea better representation of how the plant would perform in realapplications.The results show that, under the assumptions made, the AA-CAESplant's overall storage efficiency is influenced very weakly byalterations of the charge-discharge patterns, and that goodperformances can be expected not only for identical chargedischargeconsucutive cycles, but for any pattern that observesthe cavern pressure limits, as long as the thermal energy storageis sized wisely.In addition, a sensitivity analysis was performed in order toassess the influence of turbomachinery efficiency on overallstorage efficiency, for a specified plant layout. The results showthat the turbine efficiency is the most affecting parameter to theplant's performance, while the impact of the main compressors'sinefficiency is mitigated by the thermal recovery that takes placein the TES.The present work confirms that AA-CAES is a promising technologyand that storage efficiencies above 70% can be achieved even inrealistic production scenarios.Finally, future steps for more accurate simulations of plants'performances and more detailed energy production scenarios areproposed.MSc ET 18007Examinator: Joakim WidénÄmnesgranskare: Ane HåkanssonHandledare:
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Ladeia, Cibele Aparecida. "Formulação semi-discreta aplicada as equações 1D de convenção-difusão-reação e de Burgers." Universidade Estadual de Londrina. Centro de Ciências Exatas. Programa de Pós-Graduação em Matemática Aplicada e Computacional, 2012. http://www.bibliotecadigital.uel.br/document/?code=vtls000171429.
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Neste trabalho aplicamos a formulação semi-discreta, caracterizada pela combinação de aproximações distintas para as variáveis temporal e espacial, onde a variável temporal é discretizada utilizando métodos implícitos multi-estágios e a espacial usando métodos de elementos finitos,para a obtenção de soluções numéricas para as equações 1D de convecção-difusão-reação e de Burgers, cujas soluções analíticas são conhecidas.Métodos multi-estágios são obtidos através dos aproximantes de Padé. Em particular, neste trabalho consideramos os métodos implícitos multi-estágios de segunda ordem, R11, e de quarta ordem, R22, na discretização temporal. Quanto à discretização espacial, utilizamos três formulações do método de elementos finitos, ou seja, mínimos quadrados (MEFMQ), Galerkin (MEFG) e streamline-upwind Petrov-Galerkin (SUPG). Apresentamos análises quanto à influência dos números de Péclet e de Courant-Friedrichs-Lewy, da influência da malha e dos aproximantes de Padé R11 e R22 nas formulações MEFMQ, MEFG e SUPG. Apresentamos uma análise do erro utilizando a norma L2, comparando as soluções numéricas com a solução analítica das equações avaliadas. Verificamos que o método implícito multi-estágio de quarta ordem, R22, quando adicionado aos MEFMQ, MEFG e SUPG aumentou a região de convergênciadas soluções numéricas das equações e que o MEFMQ apresentou uma melhor performance, quando comparado as formulações MEFG e SUPG.In this work we apply the semidiscrete formulation, characterized by the combination of distinct approaches to the time and space variables, where the time variable is discretized using implicits multi-stages methods and space variable is discretized using finite element methods, for obtaning numerical solutions for the 1D convection-diffusion-reation and Burgers equations, whose analytical solutions are known. Multi-stage methods are obtained through of Padé approximants. In particular, in this work we consider of the implicit multi-stage method of second-order R11 and of fourth-order R22, for time discretization. As for space discretization, we use three formulations of the finite elements methods, namely, least square (LSFEM), Galerkin (GFEM) and streamline-upwind Petrov-Galerkin (SUPG). We present analysis of the influence of the Péclet and Courant-Friedrichs-Lewy numbers, of the influence of the grid, of the Padé approximants R11 and R22 in the formulations LSFEM, GFEM and SUPG. We present a analysis of the error using the L2-norm, comparing the numerical solutions with analytical solutions. We verify that of the implicit multi-stage method of second-order when combined with the LSFEM, GFEM and SUPG, increased region of convergence of the numerical solutions, and that LSFEM presented a better performace when compared to the GFEM and SUPG formulations.
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Medeiros, Cláudia Brunosi. "Soluções das equações de Burgers 1D e 2D via : upwind de alta ordem e Hopf-Cole." Universidade Estadual de Londrina. Centro de Ciências Exatas. Programa de Pós-Graduação em Matemática Aplicada e Computacional, 2013. http://www.bibliotecadigital.uel.br/document/?code=vtls000183051.
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No estudo em dinâmica dos fluidos computacional há o interesse em obter soluções numéricas para as equações diferenciais parciais. Um desafio neste contexto é a formação de descontiniuidades que pode ser atribuída ao tratamento do termo convectivo não linear em equações diferenciais parciais. Dentro deste cenário, neste trabalho apresenta-se o estudo de um esquema upwind de alta resolução, o esquema ADBQUICKEST (Adaptative Bounded QUICKEST). Este esquema é aplicado em equações 1D e 2D, comparando qualitativemente os resultados numéricos com as soluções analíticas obtidas via transformação de Hopf-Cole e via uma modificação na transformação de Hopf-Cole. Ainda, o esquema é investigado nas soluções da equação de Burgers 1D e no sistema acoplado de equações de Burgers 1D para diferentes condições iniciais e de fronteira. Além disso, analisam-se os resultados numéricos da equação de Burgers 2D e os resultados no sistema acoplado de equações de Burgers 2D a baixos valores de _. Por fim, investiga-se a ordem de precisão do esquema ADBQUICKEST em cada exemplo estudado.In the studies in computational fluid dynamics there is interest to obtain numerical solutions for partial differential equations. A challenge in this context is the formation of shock that can be attributed to the treatment of the nonlinear convective term in the partial differential equations. Within this scenario, this paper presents the study of a high-resolution upwind scheme, the ADBQUICKEST scheme. This scheme is applied to equation 1D and 2D, qualitatively comparing the numerical results with analytical solution obtained via Hopf-Cole transformation. Still, the scheme investigated in solutions of 1D Burgers equation and 1D coupled system of Burgers equations for different initial and boundary conditions. Furthermore, the numerical results of 2D Burgers equation and the numerical results of 2D coupled system of Burgers equations with low values of _ are analyzed. Ultimately, investigates the order of precision of the ADBQUICKEST in each example studied.
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Douimi, Mohammed. "Modélisation markovienne et optimisation numérique pour la restauration des signaux en (1D) et (2D)." Rouen, 1995. http://www.theses.fr/1995ROUES039.
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Cette thèse est consacrée à la modélisation markovienne et l'optimisation numérique pour la restauration des signaux en (1D) et (2D) bruités par un bruit blanc gaussien centré. Le principe du modèle markovien exploite le champ de Markov et de Gibbs sur des graphes finis via le théorème d'Hammersley Clifford. Le signal restauré est estimé au sens du critère du maximum a posteriori (MAP), qui conduit à un problème d'optimisation globale mixte, non convexe et de très grande taille, réputé très difficile. Plusieurs méthodes ont été proposées notamment le recuit simulé (SA), le graduted non convexity (GNC) et le recuit par champ moyen (MFA) introduits respectivement par (GG84), (BLA87) et (GEI89). Nous proposons des variantes de GNC 1er et 2eme ordre et surtout un nouvel algorithme que nous appelons balayage par position de discontinuité (BPD). Ce nouvel algorithme s'inspire des méthodes de coupe énumérative en optimisation combinatoire. Il se démarque des autres algorithmes cités par sa nature parallélisable, sa rapidité et sa facilite pour le choix des paramètres de lissage et de sensibilité. Ainsi, par exemple, dans le cas du signal en (1D) un traitement assisté ou automatique est proposé selon le degré de connaissance du signal à restaurer. De plus la souplesse de l'algorithme BPD permet d'introduire d'autres types de fonctions d'énergie élargissant le champ des applications (applications contour-image).
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Peterson, James B. "Comparison of Analysis and Optimization Methods for Core-Megacolumn-Outrigger Skyscrapers." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2834.
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The goal of this research is to compare performance of three analysis methods and three optimization methods for core-megacolumn-outrigger, or CMO skyscrapers. The three analysis methods include a 1D stick analysis, 2D frame analysis, and 3D finite element analysis. The three optimization methods include a trial and error optimization, optimality criteria optimization, and genetic algorithm. Each of these methods was compared by applying an example CMO skyscraper. The 1D stick analysis proved to be the most accurate when compared with the 3D finite element results. The genetic algorithm was recommended as the best optimization method in this research. The 1D stick method in this thesis introduces a new analysis involving an outrigger modification factor. The comparison of these optimization methods for skyscrapers has not been reported in the literature.
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Yang, Minhao. "Conception rationnelle de nano-hybrides de carbone 1D pour l'application de nanocomposites diélectriques." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLC088/document.
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Les nanocomposites polymères diélectriques ayant une constante diélectrique élevée et une faible perte diélectrique ont reçu un grand intérêt pour une utilisation dans le domaine du condensateur électrostatique. De manière générale, les performances diélectriques améliorées des nanocomposites sont déterminées par le type et la nature des polymères et des nanocharges sélectionnés, ainsi que par l'effet de couplage interfacial entre les matrices et les nanocharges. Parmi ces facteurs, les propriétés physiques, les géométries et les structures des composants des nanocharges jouent un rôle essentiel dans la détermination des performances diélectriques des nanocomposites. Selon les conductivités des nanocharges, les nanocomposites polymères diélectriques peuvent être classés en deux types: les nanocomposites polymères diélectriques conducteurs (CDPN) et les nanocomposites polymères diélectriques-diélectriques (DDPN). Cependant, la perte diélectrique élevée accompagnée au voisinage du seuil de percolation pour les CDPN et la charge élevée de nanocharges en céramique entravent le développement de nanocomposites polymères diélectriques à haute performance.Tout d'abord, des nanocomposites ternaires BNNS/CNT/PVDF ont été fabriqués. L'incorporation de BNNS dans les nanocomposites binaires CNT/PVDF a amélioré la dispersion des NTC et optimisé le réseau conducteur. La connexion directe entre les CNT pourrait être entravée en augmentant le contenu de BNNS.Deuxièmement, des hybrides CNT@AC à structure cœur-coquille ont été préparés par méthode CVD. La couche de carbone amorphe entrave non seulement le contact direct des NTC, mais améliore également la dispersibilité des NTC dans la matrice de PVDF. Le seuil de percolation augmente avec la prolongation du temps de dépôt du carbone. Plus important encore, la perte diélectrique a subi une forte diminution après le processus de revêtement. Troisièmement, les hybrides BNNSs@C avec des teneurs en carbone différentes ont été synthétisés par la méthode CVD. La fraction de carbone dans les hybrides BNNSs@C pourrait être ajustée avec précision en contrôlant le temps de dépôt de carbone. Les propriétés diélectriques des nanocomposites BNNSs@C/PVDF pourraient être ajustées avec précision en ajustant la teneur en carbone. Les polarisations interfaciales améliorées des interfaces BNNS/C et C/PVDF ont doté les nanocomposites de performances diélectriques améliorées.Quatrièmement, les hybrides TiO2@C NW structurés en noyau et en coquille ont été synthétisés par une combinaison d'une réaction hydrothermale et du procédé CVD. L'épaisseur de la couche de carbone dans les hybrides TiO2@C NW obtenus pourrait être précisément ajustée en contrôlant le temps de dépôt du carbone. De plus, les propriétés diélectriques des nanocomposites TiO2@C NWs/PVDF pourraient être ajustées avec précision en ajustant l'épaisseur de la coque en carbone. Les polarisations interfaciales améliorées des interfaces TiO2/C et C/PVDF ont doté les nanocomposites d'excellentes performances diélectriques.Enfin, des nanofils structurés de TiO2@C@SiO2 structurés à double coques ont été synthétisés par une combinaison de réactions hydrothermales modifiées, de CVD et de réactions sol-gel. L'introduction de carbone comme enveloppe interne entre le noyau de TiO2 et l'enveloppe externe de SiO2 a induit deux types supplémentaires de polarisation interfaciale. Les nanocomposites de PVDF obtenus avec TiO2@C@SiO2 NWs présentaient simultanément une constante diélectrique améliorée et des caractéristiques de perte diélectrique supprimées. La constante diélectrique et la perte de nanocomposites ont augmenté avec l'augmentation de l'épaisseur de la couche interne de carbone et ont diminué avec l'augmentation de l'épaisseur de la couche externe de SiO2. La relation entre la perte diélectrique et l'épaisseur de l'enveloppe extérieure en SiO2 a été démontrée par les résultats de la simulation finieDielectric polymer nanocomposites with a high dielectric constant and low dielectric loss have received broad interest for use in the field of the electrostatic capacitor and they are usually composed of dielectric polymers as matrix and inorganic or organic nanofillers as the reinforcement. Generally, the improved dielectric performance of nanocomposites is decided by the type and nature of selected polymers and nanofillers as well as interfacial coupling effect between matrices and nanofillers. Among these factors, the physical properties, geometries, component structures of nanofillers play a critical role in deciding the dielectric performance of nanocomposites. According to the conductivities of nanofillers, the dielectric polymer nanocomposites can be classified into two types: conductive-dielectric polymer nanocomposites (CDPNs) and dielectric-dielectric polymer nanocomposites (DDPNs). However, the accompanied high dielectric loss in the vicinity of the percolation threshold for CDPNs and high loading of ceramic nanofillers hinders the development of high performance dielectric polymer nanocomposites.Firstly, ternary BNNSs/CNTs/PVDF nanocomposites were fabricated. The incorporation of BNNSs into the binary CNTs/PVDF nanocomposites improved the dispersion of CNTs and optimized the conductive network, which contributed to the enhanced dielectric constant. The direct connection between CNTs could be hindered by increasing the content of BNNS.Secondly, core-shell structured CNTs@AC hybrids were prepared by CVD method. The amorphous carbon layer not only hindered the direct contact of CNTs but also improved the dispersibility of CNTs in the PVDF matrix. The percolation threshold increased with the prolongation of carbon deposition time. More importantly, the dielectric loss underwent a sharp decrease after the coating process, which was attributed to the decrease in leakage current. The results suggested that the influence of AC interlayer on the final dielectric performance after percolation was much more obvious than that before percolation.Thirdly, BNNSs@C hybrids with different carbon contents were synthesized by the CVD method. The carbon fraction in the BNNSs@C hybrids could be accurately adjusted through controlling the carbon deposition time. The dielectric properties of BNNSs@C/PVDF nanocomposites could be accurately tuned by adjusting the carbon content. The improved interfacial polarizations of BNNSs/C and C/PVDF interfaces endowed the nanocomposites with enhanced dielectric performance.Fourthly, core-shell structured TiO2@C NW hybrids were synthesized by a combination of a hydrothermal reaction and the CVD method. The carbon shell thickness in the obtained TiO2@C NW hybrids could be precisely tuned by controlling the carbon deposition time. The TiO2@C NWs/PVDF nanocomposites exhibited a percolative dielectric behavior. Moreover, the dielectric properties of the TiO2@C NWs/PVDF nanocomposites could be accurately adjusted by tuning the carbon shell thickness. The enhanced interfacial polarizations of the TiO2/C and C/PVDF interfaces endowed the nanocomposites with excellent dielectric performance.Lastly, core@double-shells structured TiO2@C@SiO2 nanowires were synthesized by a combination of modified hydrothermal reaction, CVD, and sol-gel reaction. The introducing of carbon as an inner shell between the TiO2 core and SiO2 outer shell induced two additional types of interfacial polarization. The obtained PVDF nanocomposites with TiO2@C@SiO2 NWs exhibited simultaneously enhanced dielectric constant and suppressed dielectric loss characteristics. The dielectric constant and loss of nanocomposites increased with the increase of carbon inner shell thickness and decreased with the increasing of SiO2 outer shell thickness. The relationship between the dielectric loss and SiO2 outer shell thickness was further demonstrated by the finite simulation results
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Morber, Jenny Ruth. "1D nanowires understanding growth and properties as steps toward biomedical and electrical application /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24825.
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Thesis (Ph.D.)--Materials Science and Engineering, Georgia Institute of Technology, 2009.Committee Chair: Snyder, Robert; Committee Co-Chair: Wang, Zhong Lin; Committee Member: El-Sayed, Mostafa; Committee Member: Milam, Valeria; Committee Member: Summers, Christopher; Committee Member: Wong, C. P.
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CROS, François. "Confluences, remplissage et vidange: deux aspects singuliers du système veineux jambier." Phd thesis, Université Paris-Diderot - Paris VII, 2003. http://tel.archives-ouvertes.fr/tel-00004089.
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L'objectif de ce travail est de contribuer à la modélisation globale du système veineux jambier entrepris par les Laboratoires Innothera, en étudiant deux de ces aspects singuliers. La première partie porte sur les confluences. A l'aide d'une étude numérique validée expérimentalement nous proposons deux modèles permettant, d'une part de prédire la perte de charge singulière d'une confluence en fonction de sa géométrie et de son régime d'écoulement et, d'autre part, de prendre en compte les effets non newtoniens du sang en introduisant une viscosité dont la valeur dépend du débit. La seconde partie porte sur le remplissage et la vidange d'un tuyau souple. A l'aide d'un banc hydrodynamique nous avons développé une méthode de mesure de loi d'état de ces tuyaux et un modèle rendant compte de la cinématique de leur paroi. Enfin, nous avons réalisé la validation d'un code de simulation numérique permettant de résoudre le problème de l'écoulement d'un fluide dans une conduite déformable.
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Di, Chicco Augusto. "Optimization of a calculation scheme through the parametric study of effective nuclear cross sections and application to the estimate of neutronic parameters of the ASTRID fast nuclear reactor." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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This thesis presents the project for the optimization of the APOLLO3® neutronic calculation scheme applied to the 4th generation fast neutron reactor ASTRID. APOLLO3® is the new multipurpose neutronic platform developed by the CEA. It incorporates many of the previous generation codes used in the French reactor core design supply chain. Like all deterministic codes, APOLLO3® solves the neutron transport equation with a discretization of the variables of interest: multi-group method for the energy, discrete ordinates and spherical harmonics for the angular variable, collision probabilities and characteristics methods for the spatial variable. The resolution of the transport equation handles useful quantities such as the neutron flux and multiplication factor, fission rates and cross sections to understand the physical behaviour of the reactor core. Currently it is not possible to use deterministic codes to simulate an entire reactor with a heterogeneous 3D geometry and a fine energy description, so to simplify the study of complete neutron field at core level, the calculation scheme is divided into two phases: lattice and core calculation. The main purpose of this work is to find an optimal degree of approximations of the calculation scheme for the evaluation of a desired physical effect and of the user constraints. In order to reach this optimum, several studies have been carried out with different levels of approximations. The results have been benchmarked with the ones obtained using the stochastic code TRIPOLI4®, used as a reference and to ensure a good accuracy. Furthermore, several sensitivity studies have been carried out to understand how the different approximations affect the macroscopic cross sections evaluation, because these dependences are not yet fully understood.
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Liu, Erming. "Synthesis of one-dimensional nanocomposites based on alumina nanofibres and their catalytic applications." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/48323/1/Erming_Liu_Thesis.pdf.
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Materials with one-dimensional (1D) nanostructure are important for catalysis. They are the preferred building blocks for catalytic nanoarchitecture, and can be used to fabricate designer catalysts. In this thesis, one such material, alumina nanofibre, was used as a precursor to prepare a range of nanocomposite catalysts. Utilising the specific properties of alumina nanofibres, a novel approach was developed to prepare macro-mesoporous nanocomposites, which consist of a stacked, fibrous nanocomposite with a core-shell structure. Two kinds of fibrous ZrO2/Al2O3 and TiO2/Al2O3 nanocomposites were successfully synthesised using boehmite nanofibers as a hard temperate and followed by a simple calcination. The alumina nanofibres provide the resultant nanocomposites with good thermal stability and mechanical stability.
A series of one-dimensional (1D) zirconia/alumina nanocomposites were prepared by the deposition of zirconium species onto the 3D framework of boehmite nanofibres formed by dispersing boehmite nanofibres into a butanol solution, followed by calcination at 773 K. The materials were characterised by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscope (TEM), N2 adsorption/desorption, Infrared Emission Spectroscopy (IES), and Fourier Transform Infrared spectroscopy (FT-IR). The results demonstrated that when the molar percentage, X, X=100*Zr/(Al+Zr), was > 30%, extremely long ZrO2/Al2O3 composite nanorods with evenly distributed ZrO2 nanocrystals formed on their surface. The stacking of such nanorods gave rise to a new kind of macroporous material without the use of any organic space filler\template or other specific drying techniques. The mechanism for the formation of these long ZrO2/Al2O3 composite nanorods is proposed in this work.
A series of solid-superacid catalysts were synthesised from fibrous ZrO2/Al2O3 core and shell nanocomposites. In this series, the zirconium molar percentage was varied from 2 % to 50 %. The ZrO2/Al2O3 nanocomposites and their solid superacid counterparts were characterised by a variety of techniques including 27Al MAS-NMR, SEM, TEM, XPS, Nitrogen adsorption and Infrared Emission Spectroscopy. NMR results show that the interaction between zirconia species and alumina strongly correlates with pentacoordinated aluminium sites. This can also be detected by the change in binding energy of the 3d electrons of the zirconium.
The acidity of the obtained superacids was tested by using them as catalysts for the benzolyation of toluene. It was found that a sample with a 50 % zirconium molar percentage possessed the highest surface acidity equalling that of pristine sulfated zirconia despite the reduced mass of zirconia. Preparation of hierarchically macro-mesoporous catalyst by loading nanocrystallites on the framework of alumina bundles can provide an alternative system to design advanced nanocomposite catalyst with enhanced performance.
A series of macro-mesoporous TiO2/Al2O3 nanocomposites with different morphologies were synthesised. The materials were calcined at 723 K and were characterised by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscope (TEM), N2 adsorption/desorption, Infrared Emission Spectroscopy (IES), and UV-visible spectroscopy (UV-visible). A modified approach was proposed for the synthesis of 1D (fibrous) nanocomposite with higher Ti/Al molar ratio (2:1) at lower temperature (<100oC), which makes it possible to synthesize such materials on industrial scale.
The performances of a series of resultant TiO2/Al2O3 nanocomposites with different morphologies were evaluated as a photocatalyst for the phenol degradation under UV irradiation. The photocatalyst (Ti/Al =2) with fibrous morphology exhibits higher activity than that of the photocatalyst with microspherical morphology which indeed has the highest Ti to Al molar ratio (Ti/Al =3) in the series of as-synthesised hierarchical TiO2/Al2O3 nanocomposites. Furthermore, the photocatalytic performances, for the fibrous nanocomposites with Ti/Al=2, were optimized by calcination at elevated temperatures. The nanocomposite prepared by calcination at 750oC exhibits the highest catalytic activity, and its performance per TiO2 unit is very close to that of the gold standard, Degussa P 25. This work also emphasizes two advantages of the nanocomposites with fibrous morphology: (1) the resistance to sintering, and (2) good catalyst recovery.
Book chapters on the topic "1D code"
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Tornow, Giordana, and Rupert Klein. "A 1D Multi-Tube Code for the Shockless Explosion Combustion." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 321–35. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-98177-2_20.
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Bella, Gino, Fabio Bozza, Alessandro De Maio, Francesco Del Citto, and Salvatore Filippone. "An Enhanced Parallel Version of Kiva–3V, Coupled with a 1D CFD Code, and Its Use in General Purpose Engine Applications." In High Performance Computing and Communications, 11–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/11847366_2.
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Almeida, Paulo, Diego Napp, and Raquel Pinto. "From 1D Convolutional Codes to 2D Convolutional Codes of Rate 1/n." In Coding Theory and Applications, 25–33. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-17296-5_2.
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Sakata, Shojiro, and Masazumi Kurihara. "A fast parallel implementation of the Berlekamp-Massey algorithm with a 1D systolic array architecture." In Applied Algebra, Algebraic Algorithms and Error-Correcting Codes, 415–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/3-540-60114-7_32.
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"1D hp Code." In Computing with hp-ADAPTIVE FINITE ELEMENTS, 85–98. Chapman and Hall/CRC, 2006. http://dx.doi.org/10.1201/9781420011685-9.
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"1D hp Code." In Chapman & Hall/CRC Applied Mathematics & Nonlinear Science, 57–70. Chapman and Hall/CRC, 2006. http://dx.doi.org/10.1201/9781420011685.ch4.
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Hinkle, Lee B., Gentry Atkinson, and Vangelis Metsis. "An End-to-End Methodology for Semi-Supervised HAR Data Collection, Labeling, and Classification Using a Wristband." In Ambient Intelligence and Smart Environments. IOS Press, 2022. http://dx.doi.org/10.3233/aise220066.
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This work presents a semi-automated labeling system for Human Activity Recognition (HAR) datasets. A 1D-CNN trained on scripted activities is used to generate predicted labels for free-form walking segments. Labels below a confidence threshold are marked for review using closed captioned video reducing the time required to label the unscripted sequences. The publicly available TWristAR dataset collected for this work includes Empatica e4 wristband data recorded during six HAR activities and free-form walks. A complete time-stamped video record is provided which we believe makes this dataset unique and useful. Our 1D-CNN model achieves a subject-dependent accuracy of 96.4% and a subject-independent accuracy of 77.4% for six scripted activities. The source code for this work is available at https://github.com/imics-lab/Semi-Supervised-HAR-e4-Wristband.
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Aubin, Philippe, Brian P. d’Entremont, David Sturzenegger, Rémy Haynau, Joseph R. H. Schaadt, and John R. Thome. "1D Mechanistic Model and Simulation Code for Closed-Loop Pulsating Heat Pipes." In Encyclopedia of Two-Phase Heat Transfer and Flow IV, 141–208. WORLD SCIENTIFIC, 2018. http://dx.doi.org/10.1142/9789813234406_0003.
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Pandey, Anukul, Butta Singh, Barjinder Singh Saini, and Neetu Sood. "Nonlinear Complexity Sorting Approach for 2D ECG Data Compression." In Computational Tools and Techniques for Biomedical Signal Processing, 1–21. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0660-7.ch001.
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Cardiovascular Disease (CVD) is globally acknowledged research problem. The continuous Electrocardiogram (ECG) monitoring can assist in tackling the problem of CVD. The redundancy in the monitoring of ECG signal is reduced by various signal processing techniques either in 1D or 2D domain. This chapter is having the sole objective of reviewing the existing 2D ECG data compression techniques and comparing it with the 1D compression techniques. Furthermore, proposing a novel nonlinear complexity sorting approach for 2D ECG data compression. The broad basic steps involved in the procedure are preprocessing, transformation and encoding. The preprocessing steps includes QRS detection, 2D ECG image formulation, Dc quantization and complexity sorting. The second stage of transformation includes the various decomposition techniques. At encoding stage, standard image codec (JPEG2000) can be employed. The performance evaluation of the proposed complexity sorting algorithm is performed on records of Massachusetts Institute of Technology – Beth Israel Hospital arrhythmia database.
Conference papers on the topic "1D code"
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Liang, Liang, Zhouyu Liu, Hongchun Wu, Sheng Wang, Qian Zhang, and Qiang Zhao. "Development and Application of a 2D/1D Fusion Code With Leakage Reconstruction Method." In 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81507.
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The 2D/1D fusion method (2D/1D method) is becoming a popular transport method for whole-core calculations, which reduces the group condense and assembly homogenization approximations in the conventional two-step reactor physics calculations. In most 2D/1D codes, a pin is chosen as a 1D calculation domain, which assumes that the axial leakage of the pin is flat on top/bottom surfaces. Similar to the axial leakage, the radial leakage of every 2D plane also introduces several approximations along axial direction for the 1D calculation. In this paper a 2D/1D fusion code is developed, while a leakage reconstruction method is proposed and applied. In this 2D/1D fusion code, MOC is applied to the radial 2D calculation and the Sn diamond difference method is used for the axial 1D calculation. Numerical results indicate that the 2D/1D fusion code developed in this paper is precise in three-dimensional transport calculation and show the performance of this leakage reconstruction method especially when the leakage term is significant.
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Lopes, D. T., and C. C. Motta. "1D large signal time-domain code for TWT." In 2011 IEEE Pulsed Power Conference (PPC). IEEE, 2011. http://dx.doi.org/10.1109/ppc.2011.6191448.
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Rasooli, N., S. Besharat Shafiei, and H. Khaledi. "Combination of 1D Code and CFD for Performance Analysis of a Silo Type Gas Turbine Combustor." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23319.
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Whereas Gas Turbines are the most important producers of Propulsion and Power in the world and with attention to the importance of combustion chamber as one of the three basic components of Gas Turbine, various activities in different levels have been done on this component. Because of the environmental limitations and laws related to the pollutants such as NOx and CO, Lean Premixed Combustion Chambers are specially considered in gas turbine industries. This study is part of a Multi-Layer simulation of the whole gas turbine cycle in MPG Company. In this work, the combination of a general 1D code and CFD is used for deriving appropriate performance curves for a 1D and 0D gas turbine design, off-design and dynamic cycle code. This 1D code is a general code which has been developed for different combustion chambers; annular, can-annular, can type and silo type combustion chambers. The purpose of generating this 1D code is the possibility of fast analysis of combustors in different operating conditions and reaching required outputs. This 1D code is a part of a general simulation 1D code for gas turbine and was used for a silo type combustor performance prediction. This code generates required quantities such as pressure loss, exit temperature, liner temperature and mass distribution through the combustion chamber. Mass distribution and pressure loss are analyzed and determined with an electrical analogy. Results derived from 1D code are validated with empirical data available for different combustors. There is appropriate agreement between these experimental and analytical results. Drag coefficients for liner holes are available from experimental data and for burner are calculated as a curve with CFD simulations. What differs this code from other 1D codes for gas turbine combustors is the advantage of using combustion efficiencies evolved from numerical simulation results in different loads. These efficiencies are determined with CFD simulations and are available as maps and inserted into the gas temperature calculation algorithm of 1D code. In other 1D codes in this field, empirical correlations are used for combustion efficiency determination. Combustion efficiency curves for design and off-design conditions in this study are achieved by 2D and 3D simulation of combustion chamber with application of EBU/Finite Rate model and 8 step reactions of CH4 burning. Diffusion flame in low loads and premixed flame in high loads are considered. Flame stability and Lean Blow Out charts are evolved from CFD simulation and Heat transfer is applied with empirical correlations.
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Trindade, Wagner Roberto da Silva, and Rogério Gonçalves dos Santos. "Combustion Modeling Applied to Engines Using a 1D Simulation Code." In 25th SAE BRASIL International Congress and Display. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2016. http://dx.doi.org/10.4271/2016-36-0347.
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Yoshimura, Kazuo, Norihiro Doda, Tatsuya Fujisaki, Kennichi Igawa, Masaaki Tanaka, and Hidemasa Yamano. "Application of 1D-CFD Coupling Method to Unprotected Loss of Heat Sink Event in EBR-II Focusing on Thermal Stratification in Cold Pool." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-89259.
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Abstract Negative reactivity caused by radial expansion of core is known as one of the inherent safety features in a sodium-cooled fast reactor (SFR). In order to confirm the applicability of the reactivity model, the authors have been conducting the benchmark exercises of the unprotected loss of heat sink event tests in a pool-type experimental SFR EBR-II. In the blind phase in the benchmark analyses using the in-house plant dynamics analysis (1D) code, it was found the increase of the core inlet temperature was evaluated lower than that of the measured data and the feedback reactivity was underestimated. Since the discrepancies might be brought by the ignorance of thermal stratification in the cold pool by means of the perfect mixing model in the 1D code, the detailed model of the cold pool for the computational fluid dynamics (CFD) code was introduced and the 1D-CFD codes coupling method was applied to the benchmark analyses. Then, it was confirmed that both the thermal stratification in the cold pool and the core inlet temperature were successfully reproduced. It could insist that modeling the cold pool including the IHX outlet window in detail was important to simulate the thermal hydraulics behaviors including thermal stratification there.
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Wurzenberger, Johann C., and Bernhard J. Peters. "Catalytic Converters in a 1d Cycle Simulation Code Considering 3d Behavior." In SAE 2003 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2003. http://dx.doi.org/10.4271/2003-01-1002.
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Qiu, Yishu, Manuele Aufiero, Kan Wang, and Massimiliano Fratoni. "Generalized Sensitivity Analysis With Continuous-Energy Monte Carlo Code RMC." In 2016 24th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icone24-60473.
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A new capability for computing sensitivity coefficients of bilinear response functions has been developed in the Reactor Monte Carlo code RMC based on the collision history-based method. Originally implemented in the Monte Carlo code SERPENT2 in the frame of Delta-tracking technique, this method computes the perturbation of particle weight based on the concept of accepted events and rejected events. The implementation of this method in RMC is based on ray-tracking technique. The new capability in RMC has been verified by comparing sensitivity coefficients of adjoint-weighted kinetic parameters including effective prompt lifetime and effective delayed neutron fraction from SERPENT2 as well as two deterministic codes based on Equivalent Generalized Perturbation Theory (EGPT), TSUNAMI-1D and SUSD3D, through two fast metallic systems, the Jezebel and flattop problems. Good agreement among RMC, SERPENT2, SUSD3D and TSUNAMI-1D (EGPT) is observed.
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Nentvich, Ondrej, Martin Urban, Martin Blažek, Adolf Inneman, Rene Hudec, and Ladislav Sieger. "Lobster eye optics: position determination based on 1D optics with simple code mask." In Advances in X-Ray/EUV Optics and Components XIV, edited by Christian Morawe, Ali M. Khounsary, and Shunji Goto. SPIE, 2019. http://dx.doi.org/10.1117/12.2528505.
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Buyko, Anatoly M. "Disc Explosive Magnetic Generator and Quasi-Spherical Liner Simulations with a 1D Code." In 2006 International Conference on Megagauss Magnetic Field Generation and Related Topics. IEEE, 2006. http://dx.doi.org/10.1109/megaguss.2006.4530690.
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Kalogerakos, Stamatis, Mustapha Gourma, and Chris Thompson. "Validation of 2D CFD for Two-Phase Transient Flow in a Channel and Comparison With 1D Model." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-87506.
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Severe limitations of the use of three-dimensional computational fluid dynamics codes (CFD) arise when trying to simulate multiphase flow in long pipes due to time constraints. 1D codes for two-phase flow, based on two-fluid models, are fast but are known to be accurate only when the velocities are within the Kelvin-Helmholtz inviscid limit [1]. An alternative is to carry out a two-dimensional CFD simulation of a channel based on the Volume of Fluid (VOF) model. 2D CFD has a wider applicability range compared to 1D, it does not have the issue of ill-posedness and it also has better turbulence models built in. Again compared to 1D the 2D VOF model has a better interface description and wall treatment. In this paper a novel method is introduced that allows swift simulations of pipeline two-phase flow in the stratified and slug flow regime, by approximating the pipe as a channel and with a methodology that solves the problem of the interfacial velocity differences, inherent in the volume of fluid model. An initial validation using the wave growth problem has already been carried out [2]. Here a set consisting of 92 experimental cases in the slug flow regime has been simulated with 2D CFD, and the simulation results showed a good agreement with experimental results. Discussions in the paper include also the question of the range of applicability for 2D CFD, and the advantages and disadvantages compared to 3D CFD and also to 1D code based on the two-fluid model. Shear stresses are then extracted from the 2D CFD simulations and used to recalibrate the friction factors [3] used in the 1D code.
Reports on the topic "1D code"
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Kasinathan, N., A. Rajakumar, G. Vaidyanathan, and S. C. Chetal. Simulation of decay heat removal by natural convection in a pool type fast reactor model-ramona-with coupled 1D/2D thermal hydraulic code system. Office of Scientific and Technical Information (OSTI), September 1995. http://dx.doi.org/10.2172/107783.
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