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Academic literature on the topic 'Zig-zag model'

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Published: 14 March 2023

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Journal articles on the topic "Zig-zag model"

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Aloui, Lobna, Thierry Dintzer, and Izabela Janowska. "Fe Atom—Mixed Edges Fractal Graphene via DFT Calculation." ChemEngineering 6, no. 5 (October 8, 2022): 79. http://dx.doi.org/10.3390/chemengineering6050079.

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The stability of small fractal graphene models with two different symmetries and Fe atoms at their mixed edges is addressed by density functional theory (DFT) calculations. Four kinds of edge configurations and Fe atom localizations are determined depending on the model. The edges have mixed configuration, the zig-zag and “intra-zig-zag” in symmetrical structures and armchair and zig-zag type in the architectures with rotational symmetry. The rotational symmetry graphene exhibits slightly higher stability per carbon atom compared to the symmetrical model, while the localization of Fe atoms is more favorable at armchair and “inversed zigzag” than at zigzag type carbon termination. Larger graphene structures with rotational symmetry were observed previously via experimental cutting of graphene with Fe nanoparticles (NPs).
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Yuniati, Yuniati. "Perancangan Sistem Autopilot untuk Kontrol Kemudi Model Kapal Mengunakan Programable Automatic Controller Ni Compactrio." Wave: Jurnal Ilmiah Teknologi Maritim 9, no. 2 (January 11, 2018): 65–70. http://dx.doi.org/10.29122/jurnalwave.v9i2.2659.

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Perancangan sistem autopilot pada sebuah alat/sistem kemudi mempunyai peranan sangat penting, yang nantinya akan mempengaruhi hasil akhir dan kinerja sistem kemudi yang akan dijalankan. Paper ini membahas tentang perancangan sebuah sistem kontrol/pengendali otomatis yang dapat diprogram dengan menggunakan CompactRIO NI cRIO sebagai perangkat yang menjalankan sistem Autopilot. Perancangan sistem autopilot ini divalidasi melalui simulasi uji zig-zag model kapal dan dari hasil validasi ini didapatkan bahwa sistem kontrol ini berfungsi dan mampu melakukan lintasan zig-zag sesuai yang diharapkan.
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Coddé, Joris, Wim Van der Veken, and Martine Baelmans. "The Effect of Mass Flow Distribution Inaccuracies in a Hydraulic Network Model for OD Zig-Zag Cooled Power Transformer Windings." Applied Mechanics and Materials 789-790 (September 2015): 336–41. http://dx.doi.org/10.4028/www.scientific.net/amm.789-790.336.

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In this paper the mass flow distribution in zig-zag cooled power transformer windings is shown to play a crucial factor to accurately predict the winding temperature. In order to enable thermo-hydraulic network models for transformer design, new correlations are derived for combining and dividing T-junctions and elbow configurations. Good correspondence is achieved in comparison with CFD simulation results for a zig-zag cooled power transformer winding.
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Christiansen, P. L., A. V. Savin, and A. V. Zolotaryuk. "Zig-zag version of the Frenkel-Kontorova model." Physical Review B 54, no. 18 (November 1, 1996): 12892–902. http://dx.doi.org/10.1103/physrevb.54.12892.

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Liu, Xiongjun, Yuqin Fan, Tao Mo, Qingxiu Chen, and Weiting Chen. "Comparative Study of the Gut Microbiota Community between the Farmed and Wild Mastacembelus armatus (Zig-Zag Eel)." Metabolites 12, no. 12 (November 29, 2022): 1193. http://dx.doi.org/10.3390/metabo12121193.

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Cultivated and wild fish of the same species may exhibit different characteristics, such as in their flavor, growth and development. In some wild fish species, reproductive functions may even be retarded when wild individuals are moved into cultivated conditions. The gut microbiota may be one of the reasons for these phenomena as they have been reported to play an important role in host growth and development, as well as in normal reproductive functioning. Here, we used Mastacembelus armatus (zig-zag eel), a freshwater fish which shows anormal reproductive function in cultivated conditions, as a model to comparatively study the diversity, structure and function of gut microbiota in cultivated and wild groups by analyzing the 16S rRNA sequence of each group’s microbiota. The results showed that Proteobacteria and Firmicutes were the dominant phyla in the gut microbiota of wild (accounting for 45.8% and 20.3% of the total number of Proteobacteria and Firmicutes, respectively) and farmed (accounting for 21.4% and 75.6% of the total number of Proteobacteria and Firmicutes, respectively) zig-zag eel. Wild zig-zag eels (Shannon = 3.56; Chao = 583.08; Ace = 579.18) had significantly higher alpha diversity than those in cultivated populations (Shannon = 2.09; Chao = 85.45; Ace = 86.14). A significant difference in the community structure of the gut microbiota was found between wild and cultivated populations. The wild zig-zag eel showed a high abundance of functional pathways in metabolism, genetic information processing and organismal system function. These results suggested that the diversity and function of gut microbiota in zig-zag eel were correlated with their diet and habitat conditions, which indicated that the management of cultivated populations should mimic the wild diet and habitat to improve the productivity and quality of farmed zig-zag eel.
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Fei, Qili, Yu Zhang, Rui Xia, and Blake C. Meyers. "Small RNAs Add Zing to the Zig-Zag-Zig Model of Plant Defenses." Molecular Plant-Microbe Interactions® 29, no. 3 (March 2016): 165–69. http://dx.doi.org/10.1094/mpmi-09-15-0212-fi.

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Plant small RNAs play important roles in transcriptional and posttranscriptional regulation, with ongoing work demonstrating their functions in diverse pathways. Their roles in defense responses are a topic of active investigation, particularly the rich set of micro (mi)RNAs that target disease resistance genes such as nucleotide binding/leucine-rich repeat (NB-LRR) genes. The miRNA–NB-LRR interactions result in the production of phased, secondary small interfering (phasi)RNAs, and phasiRNAs function in both cis and trans to propagate negative regulatory effects across additional members of the target gene family. Yet, while phasiRNAs have the capacity to trigger targeted decay of specific targets, both in cis and trans, their functional relevance in NB-LRR regulation remains largely a matter of speculation.
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Kapuria, S. "A Coupled Zig-Zag Third-Order Theory for Piezoelectric Hybrid Cross-Ply Plates." Journal of Applied Mechanics 71, no. 5 (September 1, 2004): 604–14. http://dx.doi.org/10.1115/1.1767170.

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A new zig-zag coupled theory is developed for hybrid cross-ply plates with some piezoelectric layers using third-order zig-zag approximation for the inplane displacements and sublayer wise piecewise linear approximation for the electric potential. The theory considers all electric field components and can model open and closed-circuit boundary conditions. The deflection field accounts for the transverse normal strain due to the piezoelectric d33 coefficient. The displacement field is expressed in terms of five displacement variables (which are the same as in FSDT) and electric potential variables by satisfying exactly the conditions of zero shear stresses at the top and bottom, and their continuity at layer interfaces. The governing equations are derived from the principle of virtual work. Comparison of the Navier solutions for the simply-supported plates with the analytical three-dimensional piezoelasticity solutions establishes that the present efficient zig-zag theory is quite accurate for moderately thick plates.
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Kavcic, A., and J. M. F. Moura. "Experimental validation of the triangle zig-zag transition model." IEEE Transactions on Magnetics 33, no. 5 (1997): 2704–6. http://dx.doi.org/10.1109/20.617451.

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Pavlinovic, Vladimir, Miodrag Spasic, Nikola Foretic, Dean Kontić, and Nataša Zenić. "Differential Influence of General Anthropometric and Motor Predictors on Pre-planned Agility in Pubescent Boys and Girls: A Multiple Regression Study." Sport Mont 20, no. 2 (June 1, 2022): 75–81. http://dx.doi.org/10.26773/smj.220612.

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In this study, we investigated the influence of balance, jumping power, and speed as well as morphological variables for three different agility tests in early pubescent boys (n=73) and girls (n=63). The predictors included body height and mass, body fat, high jumps, the overall stability index, ankle mobility, and a 10 and a 15 m sprint. The statistical analysis included calculations of correlations, regression models for the correlated variables, and the validation of the regression models. The calculated regression models for the male group explained 38% of the variance in a Zig-Zag test, 12% in a 20-yard test (20Y), and 81% in a T-test. The significant regression model for the Zig-Zag test included body mass, high jumps, and a 10 m sprint. The 20Y test had no predictors in the male group. For the T-test, the only predictor was the 10 m sprint. The calculated regression models for the female group explained 57% of the variance in the Zig-Zag test, 32% in the 20Y test, and 42% in the T-test. The significant regression model in the female group included only the 10 m sprint for all three agility criteria. The regression models were cross-validated using the second half of the sample (boys: n=36; girls: n=31). The correlation between the predicted and the achieved scores provided a statistically significant validation for all agility tests.
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Icardi, U., and L. Ferrero. "Layerwise zig-zag model with selective refinement across the thickness." International Journal for Numerical Methods in Engineering 84, no. 9 (October 26, 2010): 1085–114. http://dx.doi.org/10.1002/nme.2933.

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Dissertations / Theses on the topic "Zig-zag model"

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Kennington, Raymond William. "Random allocations: new and extended models and techniques with applications and numerics." 2007. http://hdl.handle.net/2440/41885.

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This thesis provides a general methodology for classifying and describing many combinatoric problems, systematising and finding theoretical expressions for quantities of interest, and investigating their feasible numerical evaluation. Unifying notation and definitions are provided. Our knowledge of random allocations is also extended. This is achieved by investigating new processes, generalising known processes, and by providing a formal structure and innovative techniques for analysing them. The random allocation models described in this thesis can be classified as occupancy urn models, in which we have a sequence of urns and throw balls into them, and investigate static, waiting-time and dynamic processes. Various structures are placed on the relationship(s) between cells, balls, and the selection of items being distributed, including varieties, batch arrivals, taboo sets and blocking sets. Static, waiting-time and dynamic processes are investigated. Both without-replacement and with-replacement sampling types are considered. Emphasis is placed on the distributions of waiting-times for one or more events to occur measured from the time a particular event occurs; this begins as an abstraction and generalisation of a model of departures of cars parked in lanes. One of several additional determinations is the platoon size distribution. Models are analysed using combinatorial analysis and Markov Chains. Global attributes are measured, including maximum waits, maximum room required, moments and the clustering of completions. Various conversion formulae have been devised to reduce calculation times by several orders of magnitude. New and extended applications include Queueing in Lanes, Cake Displays, Coupon Collector's Problem, Sock-Sorting, Matching Dependent Sets (including Genetic Code Attribute Matching and the game SET), the Zig-Zag Problem, Testing for Randomness (including the Cake Display Test, which is a without-replacement test similar to the standard Empty Cell test), Waiting for Luggage at an Airport, Breakdowns in a Network, Learning Theory and Estimating the Number of Skeletons at an Archaeological Dig. Fundamental, reduction and covering theorems provide ways to reduce the number of calculations required. New combinatorial identities are discovered and a well-known one is proved in a combinatorial way for the first time. Some known results are derived from simple cases of the general models.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1309598
Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Sciences, 2007
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Kennington, Raymond William. "Random allocations: new and extended models and techniques with applications and numerics." Thesis, 2007. http://hdl.handle.net/2440/41885.

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This thesis provides a general methodology for classifying and describing many combinatoric problems, systematising and finding theoretical expressions for quantities of interest, and investigating their feasible numerical evaluation. Unifying notation and definitions are provided. Our knowledge of random allocations is also extended. This is achieved by investigating new processes, generalising known processes, and by providing a formal structure and innovative techniques for analysing them. The random allocation models described in this thesis can be classified as occupancy urn models, in which we have a sequence of urns and throw balls into them, and investigate static, waiting-time and dynamic processes. Various structures are placed on the relationship(s) between cells, balls, and the selection of items being distributed, including varieties, batch arrivals, taboo sets and blocking sets. Static, waiting-time and dynamic processes are investigated. Both without-replacement and with-replacement sampling types are considered. Emphasis is placed on the distributions of waiting-times for one or more events to occur measured from the time a particular event occurs; this begins as an abstraction and generalisation of a model of departures of cars parked in lanes. One of several additional determinations is the platoon size distribution. Models are analysed using combinatorial analysis and Markov Chains. Global attributes are measured, including maximum waits, maximum room required, moments and the clustering of completions. Various conversion formulae have been devised to reduce calculation times by several orders of magnitude. New and extended applications include Queueing in Lanes, Cake Displays, Coupon Collector's Problem, Sock-Sorting, Matching Dependent Sets (including Genetic Code Attribute Matching and the game SET), the Zig-Zag Problem, Testing for Randomness (including the Cake Display Test, which is a without-replacement test similar to the standard Empty Cell test), Waiting for Luggage at an Airport, Breakdowns in a Network, Learning Theory and Estimating the Number of Skeletons at an Archaeological Dig. Fundamental, reduction and covering theorems provide ways to reduce the number of calculations required. New combinatorial identities are discovered and a well-known one is proved in a combinatorial way for the first time. Some known results are derived from simple cases of the general models.
Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Sciences, 2007
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Books on the topic "Zig-zag model"

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Somoza, José Carlos. Zig zag: A novel. New York, NY: Rayo, 2007.

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Zig Zag: A Novel. Harper, 2008.

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Somoza, José Carlos. Zig Zag: A Novel. Rayo, 2007.

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Somoza, José Carlos. Zig Zag: A Novel. Rayo, 2007.

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Book chapters on the topic "Zig-zag model"

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Chochliouros, I., and J. Pouget. "Transport Properties in a Two-Coupled Zig-Zag Atomic Chain Model Including Dipole-Dipole Interactions." In Nonlinear Coherent Structures in Physics and Biology, 85–89. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4899-1343-2_11.

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"Zig-Zag Model of Chromosome Fiber." In Encyclopedia of Genetics, Genomics, Proteomics and Informatics, 2132. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6754-9_18395.

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Carrera, Erasmo, and Maria Cinefra. "CLASSICAL, REFINED, ZIG-ZAG AND LAYER-WISE MODELS FOR LAMINATED STRUCTURES." In Computational and Experimental Methods in Structures, 135–72. IMPERIAL COLLEGE PRESS, 2013. http://dx.doi.org/10.1142/9781848167858_0004.

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Conference papers on the topic "Zig-zag model"

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Poiate Junior, Edgard, Renato Seixas da Rocha, A´lvaro Maia da Costa, Giuseppe Barbosa Guimara˜es, Cla´udio dos Santos Amaral, and Pablo Furtado de Souza. "Experimental Tests and Numerical Simulation in a Reduced Model in a Pipeline With ZIG-ZAG Geometry: A Parametric Study." In 2004 International Pipeline Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ipc2004-0423.

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In January 2000, PETROBRAS faced a leakage of heavy heated MF380 oil from a 0.406m pipeline in the Guanabara Bay. When interacting with the soil, the thermal structural buckling of the pipeline induced the rupture of the pipeline wall causing the oil to leak. In order to overcome this undesired phenomenon, PETROBRAS studied several new pipeline alternatives. As a result of these studies, a “ZIG-ZAG” geometry pipeline named PE-3 was adopted. Given that the oil industry applications of this kind of concept have been very few and in soil conditions different from the ones in the Guanabara Bay, a very sophisticated procedure was developed including the simulation the thermal mechanical interactions between the soil and the pipeline structure. Computer modeling was carried out using the finite element method considering the soil, the pipeline non-linear material behavior and the finite displacements. In order to validate the numerical modeling, an experimental test was carried out in a reduced model with physics similar to a ZIG-ZAG geometry pipeline (PE-3). The numerical and experimental results match and have a fine conformity. After validation of the models, numerical and experimental parametric studies were completed with various angles and wavelengths of ZIG-ZAG to evaluate the conception of the PE-3 pipeline.
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Averill, R., and Y. Yip. "An efficient thick beam theory and finite element model with zig-zag sublaminate approximations." In 36th Structures, Structural Dynamics and Materials Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1995. http://dx.doi.org/10.2514/6.1995-1211.

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Cho, Y. B., E. J. Plaskacz, R. C. Averill, and R. F. Kulak. "Explicit Dynamic Finite Element Analysis of Laminated Composite Automotive Structures Using a New Composite Plate Element." In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-1189.

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Abstract Composite materials are being considered for use in the front end structures of vehicles to help reduce overall vehicle mass and, thus, improve fuel efficiency. Acceptance of composite material in structural members will depend on their ability to do crash energy management. Numerical simulations can greatly aid in the design of these critical structures and reduce the number of crash tests. A new finite element, which is based on laminated plate theory with cubic zig-zag approximations, was developed to model the relevant mechanics that occur in composite materials during crash events. The element was cast in the internal force format for use with explicit integration solvers. In the plate theory, the in-plane displacement fields in a laminate are assumed to be piecewise cubic functions and vary in a zig-zag fashion through the thickness of the laminate. The zig-zag functions are obtained by satisfying the continuity of transverse shear stresses at layer interfaces. This in-plane displacement field assumption accounts for discrete layer effects without increasing the number of degrees of freedom as the number of layers is increased. The transverse normal strain predictions are improved by assuming a constant variation of transverse normal stress through the thickness in a laminate. The finite element is developed with the topology of an eight-noded brick. Each node has five engineering degrees of freedom, three translations and two rotations. Thus, this element can be conveniently implemented into general purpose finite element codes. Consistent and lumped mass matrices are derived. The developed element is implemented into Argonne National Laboratory’s in-house code, NEPTUNE, which utilizes explicit direct integration method. In NEPTUNE the internal force vector is calculated from the developed element at each time step. Numerical performance of the current element is investigated in this research.
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Pelletier, Etienne, C. Beguin, and S. Etienne. "Simple Model for Bubble-Wall Interaction." In ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-28458.

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We have developed a model for an ellipsoidal bubble colliding with a rigid horizontal wall based on potential flow theory. The model is then compared with experiments of air bubbles surrounded by water impacting a wall. 70 impacts were observed with bubble radius between 0.3 and 2 mm and different trajectory types (helicoidal, zig-zag). Deformation and height of the first impact are the main comparison points. The proposed model is in good agreement with the height of the rebound but tends to overestimate the maximal compression for both types of trajectories. We also propose a new relation for the viscous drag coefficient correction induced by the wall confinement as well as the definition of potential pressure forces acting on bubbles close to a wall.
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Abbasi Hoseini, Afshin, and Sverre Steen. "Ship Handling Model Validation Using In-Service Measurements." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62598.

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In this work, an alternative method is proposed for validation of ship handling models using onboard monitoring data of normal ship operations. If validation data can be collected during ship service, one can obtain a large number of “repetitions” without dedicated sea trials that are expensive. Although the accuracy of each sample will probably be less than in dedicated trials, it might be compensated by the fact that many samples will be available. As a case study, the results of simulation of the research vessel of the Norwegian University of Science and Technology (NTNU), Gunnerus, using MARINTEK’s vessel simulator (VeSim) are presented and evaluated by certain maneuvers identified from Gunnerus onboard measurements. To validate a ship simulator, it is shown that it might be better to investigate the agreement between simulation and full-scale measurements during operations similar to the ones that shall be simulated later, than just validating against standardized maneuvers such as turning circle and zig-zag tests.
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Fong, Jeffrey T., Pedro V. Marcal, Robert Rainsberger, N. Alan Heckert, and James J. Filliben. "Design of an Intelligent Python Code for Validating Crack Growth Exponent by Monitoring a Crack of Zig-Zag Shape in a Cracked Pipe." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93502.

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Abstract When a small crack is detected in a pressure vessel or piping, we can estimate the fatigue life of the vessel or piping by applying the classical law of fracture mechanics for crack growth if we are certain that the crack growth exponent is correct and the crack geometry is a simple plane. Unfortunately, for an ageing vessel or piping, the degradation will, in practice, change not only the crack growth exponent but the crack shape from a simple plane to a zig-zag pattern. To validate the crack growth exponent for an ageing vessel or piping, we present the design of an Intelligent PYTHON (IP) code to convert the information of the growing crack geometry measured by monitoring a small crack that was initially detected and subsequently continuously monitored over a period of time such that the IP-based analysis code will use the realistic zig-zag crack geometry as a series of re-meshed finite-element meshes for finding the correct crack growth exponent. Using a numerical example, we show that such an IP-assisted continuous monitoring program, using PYTHON as the management tool, TRUEGRID as the topological crack meshing tool, and two finite-element analysis codes for verifiable stress analysis, is feasible for predicting more accurately the fatigue life of a cracked vessel or piping because the material model has a field-validated crack growth exponent. Significance and limitations of this IP-assisted approach are discussed.
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Monetto, I. "A single-variable approach for layered beams with imperfect interfaces." In AIMETA 2022. Materials Research Forum LLC, 2023. http://dx.doi.org/10.21741/9781644902431-82.

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Abstract. The first-order shear deformable laminated beam problem is reformulated in terms of a fictitious bending displacement as primal variable. A fourth-order differential equation governs the problem with two additional unknown constants coming from the integration of the longitudinal displacement. With the classical six boundary conditions, the problem is complete and well posed. An isogeometric collocation scheme is developed to solve the problem numerically. The formulation is completely locking-free and satisfies high continuity requirements for the approximation functions. The results for an exemplary structure confirm the validity and the good performance of the method, which is preliminary to the single variable reformulation of a more accurate zig-zag model for laminates with perfect and imperfect interfaces.
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Abdi, Frank, Saber DorMohammadi, Jalees Ahmad, Cody Godines, Gregory N. Morscher, Sung Choi, Rabih Mansour, and Steve Gonczy. "Optimizing Ceramic Matrix Composite Interlaminar Fracture Toughness (Mode I) Wedge Test." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-58076.

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ASTM test standards for CMC’s Crack Growth Resistance (CGR) may exhibit a zig-zag (wavy) crack path pattern, and fiber bridging. The experimental parameters that may contribute to the difficulty can be summarized as: specimen width and thickness, interface coating thickness, mixed mode failure evolution, and interlaminar defects. Modes I crack growth resistances, GI were analytically determined at ambient temperature using wedge test, a modified double cantilever beam (DCB). Several Finite Element (FE) based Multi-scale modeling potential techniques were investigated: a) Multi-scale progressive failure analysis (MS-PFA); b) Virtual Crack Closure Technique (VCCT). Advantages and disadvantages of each were identified. The final modeling algorithm recommended was an integrated damage and fracture evolution methodology using combined MS-PFA and VCCT. The material tested in this study was a slurry-cast melt-infiltrated SiC/SiC composite with Tyranno ZMI fibers (Ube Industries, Kyoto, Japan) and a BN interphase. The fiber architecture consisted of eight plies of balanced 2-D woven five-harness satin. The total fiber volume fraction was about 30% with half of the fibers in the 0° direction and half in the 90° direction. All specimens had a nominal thickness of 4 mm. An alumina wedge with 18° head angle (2α) was used. In this method, a splitting force is created by inserting a vertically-moving wedge in a notch causing the arms to separate and forcing an interlaminar crack at the sharpest end of the notch The MS-PFA numerical model predicted the damage and fracture evolution and utilized the GENOA UMAT (User Material Subroutine) for Damage and FEM (Finite Element Model) stress intensity and LEFM (Linear elastic Fracture Model), Cohesive Model for Fracture. The analysis results (Fracture energy vs. crack length, Fracture energy vs. load, Fracture energy vs. crack opening displacement) matched the Mode I coupon tests and revealed the following key findings. Mode I-Wedge specimen exhibits: 1) failure mode is due to interlaminar tension (ILT) only in the interface section and a zig-zag pattern observed; 2) VCCT crack growth resistance is well matched to the test data; and 3) failure mode is a mixed mode behavior of Interlaminar tension (ILT) to interlaminar shear (ILS). The final Wedge test specimen configuration optimization includes the sensitivity of design parameters to CGR: a) wedge contact coefficient of friction; b) lever arms thickness, and c) inclined head angle, distance between the initial crack and wedge tip.
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el Moctar, Ould, Florian Sprenger, Thomas E. Schellin, and Apostolos Papanikolaou. "Numerical and Experimental Investigations of Ship Maneuvers in Waves." In ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/omae2016-54847.

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Assuring a ship’s maneuverability under diverse conditions is a fundamental requirement for safe and economic ship operations. Considering the introduction of the Energy Efficiency Design Index (EEDI) for new ships and the related decreasing installed power on ships, the necessity arose to more accurately predict the maneuverability of ships in severe seas, strong winds, and confined waters. To address these issues, extensive experimental and numerical investigations were performed within the European funded Project SHOPERA. Here, second order forces and moments for a containership and a tanker were measured in model tests and computed by solving the Reynolds-Averaged Navier-Stokes (RANS) equations. Generally, these measured and computed second order loads (drift forces and yaw moments, added resistance) compared favorably. Furthermore, the effects of waves on zig-zag and turning circle maneuvers were investigated.
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Nonino, C., S. Savino, and S. Del Giudice. "Mixing Performance of Different Serpentine Microchannels." In ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30088.

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The results of a comparative numerical study aimed at assessing the mixing performance of planar zig-zag, curvilinear and square-wave microchannels of square cross-section is presented in the paper. To evaluate the mixing enhancement characteristics of each geometry, suitable mixing indices are computed at different axial locations of a single repetitive module of each microchannel when this is fed with two equal streams of fluid having the same thermophysical properties, but different solute concentrations. To separate the effects of the geometry from those of molecular diffusion, entrance flow and channel length, the mixing by pure diffusion in straight microchannels of the same length is also evaluated for comparison. Reynolds numbers in the range from 5 to 150 are considered, while the Pe´clet number is held constant and equal to 2500. All the numerical simulations are carried out using an in-house finite element code for the solution of all model equations.
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