Journal articles: '3D ring model'

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Dlugoš, Jozef, and Pavel Novotný. "Computational Modelling of Piston Ring Dynamics in 3D." Journal of Middle European Construction and Design of Cars 12, no. 3 (December 1, 2014): 1–7. http://dx.doi.org/10.2478/mecdc-2014-0009.

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Shrnutí Pokročilé výpočtové modely pístní skupiny na základě virtuálních prototypů vyžadují mimo jiné i detailní popis dynamického chování pístního kroužku. Z tohoto hlediska je zřejmé, že pístní kroužky pracují v podmínkách, které obecně nelze zjednodušit na často využívaný osově symetrický model. Píst a vložka válce nemají dokonale kruhový tvar především v důsledku výrobních tolerancí a vnějšího tepelně-mechanického zatížení. V případech, kdy kroužek nedokáže kopírovat deformace vložky, nastane lokální ztráta kontaktu a následně i zvýšený profuk spalin a spotřeba oleje. V současné době využívané výpočtové modely nejsou schopné zahrnout všechny podstatné efekty. Článek se zaměřuje na tvorbu 3D poddajného modelu pístního kroužku s využitím Timoshenkovy teorie prutů a Multibody systému (MBS). Vytvořený výpočetní model je porovnán s numerickým řešením na základě metody konečných prvků (FEM).

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Jovanovic, Igor, Ugljesa Jovanovic, and Dragan Mancic. "A Matlab/Simulink 3D model of unsymmetrical ultrasonic sandwich transducers." Serbian Journal of Electrical Engineering 15, no. 1 (2018): 41–52. http://dx.doi.org/10.2298/sjee1801041j.

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Ultrasonic sandwich transducer is a half-wave resonant structure which oscillates in thickness direction. This paper presents a new Matlab/ Simulink model of a prestressed unsymmetrical ultrasonic sandwich transducer, which is modeled by applying three-dimensional (3D) Matlab/Simulink models of piezoceramic rings and metal endings derived from the piezoceramic ring model. With the cascade connection of the piezoceramic rings model with metal endings model, a complete model of ultrasonic transducer is obtained. Using this model one may determine any transducer transfer function, whereat is taken into the account the external medium influence, as well as the influence of the thickness and radial modes of each transducer component. The electromechanical equivalent circuit of the hammer transducer, which represents onedimensional (1D) model, is also derived and presented in this paper. The comparisons between experimental and theoretical results are quite good and validate the new analytical 3D design approach.

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Bidone, Tamara C., Haosu Tang, and Dimitrios Vavylonis. "3D Model of Cytokinetic Ring Assembly in Fission Yeast." Biophysical Journal 106, no. 2 (January 2014): 177a. http://dx.doi.org/10.1016/j.bpj.2013.11.1004.

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Wang, Min. "Axial Spread Evolution during Hot Rolling of Large Rings with Different Sizes." Advanced Materials Research 189-193 (February 2011): 2092–95. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.2092.

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For ring rolling without axial rolls, how to effectively suppress axial spread has become an important subject. In the paper, a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for hot rolling of large rings is developed. Spread evolution of titanium alloy large rings with different sizes are explored and compared based the developed model. The main results show that (1) the spread in a ring takes on an axisymmetric distribution after the first revolution of the ring. (2) with the equivalent ratio of feed amount per revolution decreasing, the peak spread transfers from the outer layer to the inner layer for rings with different sizes.

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Neugebauer, R., Vladimír Gryc, and Hanuš Vavrčík. "3D modelling of microscopic structure of ring‑porous wood." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 57, no. 5 (2009): 221–28. http://dx.doi.org/10.11118/actaun200957050221.

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Nowadays many scientific 3D models of wood are available. These models are suitable only for simulation of physical fields movements in wood but not for educational purposes especially demonstration of microscopic structure of wood.3D structure of ring-porous hardwood species was created. European ash (Faraxinus excelsior L.) was selected due to its relatively simple wood structure than other wood species within ring-porous group. The model was created by manual modelling process in Rhinoceros 4.0 that is a software for visualization and modelling. Microslides were prepared from sample of ash to take micro photos that were used as a visual source for modelling. Beside these pictures made by authors of this paper other microphotos from wood anatomy publications were used. Created 3D model of ash is a VRML object (Virtual Reality Modelling Language). This format is available to viewing and presentation with severe freeware VRML browsers. These VRML browsers are available as a plug-in for standard internet browsers or as standalone VRML browsers. The model is useful for studying and teaching microscopic structure of ring‑porous hardwood species. It was created such a way to be as exact copy of original anatomical structure of ash wood as possible. The paper may be used as a cue for other authors to create their own 3D models of different wood kinds.

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LI, YIMING. "NUMERICAL CALCULATION OF ELECTRON ENERGY STATES FOR NANOSCOPIC InAs/GaAs QUANTUM RINGS." International Journal of Modern Physics C 14, no. 08 (October 2003): 995–1005. http://dx.doi.org/10.1142/s0129183103005789.

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In this paper we study the electron energy states for nanoscopic semiconductor quantum rings. The effective one-band Hamiltonian approximation and the Ben Daniel–Duke boundary conditions are simultaneously considered in our three-dimensional (3D) model. The rectangular and ellipsoidal torus-shaped rings have been investigated with the 3D model. The proposed model is numerically solved with nonlinear iterative method. This computational method calculates the solution without any fitting parameters and is robust for all simulation cases. For InAs/GaAs quantum rings, it is found that (1) there is a significant energy difference between the 2D and 3D models; (2) the electron energy state depends strongly on the ring shape and size; and (3) the dependency of the energy state on an external magnetic field is different from conventional 1D/2D periodical result. We find the electron energy state nonperiodically oscillates versus the applied magnetic field which is in agreement with the experimental observation.

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Zhao, Gang Yao, Ran Yang Zhang, Zheng Hua Guo, Zhan Rong Feng, and Shuai Ying. "A 3D FE Model for Roll Forming of Ring with Complex Cross Section." Advanced Materials Research 538-541 (June 2012): 788–91. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.788.

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The roll forming process is a technique for forming ring with complex cross section, which widely used in the fields of aviation, aerospace and other high technology industries. To predict and control the roll forming quality, a 3D elastic-plastic finite element (FE) model of ring with complex cross section for roll forming was developed using the explicit code ABAQUS/Explicit. During the modeling process, several key techniques are solved, such as materials modeling, geometry modeling and grid optimal design. Then the reliability of the model was verified. Furthermore, numerical simulation and analysis of the roll forming process of ring with complex cross section have been carried out by using the model. The distribution regularities of equivalent strain in the process have been analyzed. The results show that with the progressing of roll forming, the equivalent strain increase sharply in the initial stage, then slightly varies, and the W shape of ring cross section is produced gradually.

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Bidone, Tamara C., Haosu Tang, and Dimitrios Vavylonis. "Dynamic Actomyosin Network Morphology in 3D Model of Cytokinetic Ring Assembly." Biophysical Journal 108, no. 2 (January 2015): 300a. http://dx.doi.org/10.1016/j.bpj.2014.11.1632.

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Janusziewicz, Rima, and Janus S. Rahima Benhabbour. "3466 Innovative 3D Printed Intravaginal Rings: Developing AnelleO PRO, the First Intravaginal Ring for Infertility." Journal of Clinical and Translational Science 3, s1 (March 2019): 58. http://dx.doi.org/10.1017/cts.2019.137.

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OBJECTIVES/SPECIFIC AIMS: The study aims to develop and test a biocompatible 3D-printed IVRs for the mechanical and release properties of a model drug, β-estradiol, then translate these methods to the target drug, progesterone. The goals include demonstrating decoupling of mechanical and release properties of the rings, release profiles driven by geometry and efficacy in sheep animal models to evaluate device safety. METHODS/STUDY POPULATION: A novel 3D-printing platform, continuous liquid interface production (CLIP), pioneered by Carbon, enables the fabrication of complex designs on a timescale that is amenable to manufacturing. The process utilizes computational-aided design (CAD), specifying shape and geometry, which is recreated via a photopolymerization process. IVRs are fabricated with CLIP using a biocompatible resin at a rate of approximately 15 min. per ring. Rings were fabricated and assessed for the release of a model drug, β-estradiol. The process was then translated to the target drug, progesterone. Rings were evaluated for radial compression and in vitro release in simulated vaginal fluid (SVF). RESULTS/ANTICIPATED RESULTS: Intravaginal rings (IVRs) were designed and fabricated to be geometrically complex in an effort to control release. Ring geometry and subsequent pore size was achieved through the use of unit cells. Several design parameters were explored including unit cell type, size, and band presence in two resins of differing mechanical properties. Through design, a wide range of radial compressive properties were achieved which spanned values covered by commercially available rings. The release of β-estradiol in SVF was found to span 57 – 115 days and resulted in near or complete release of the total loaded drug. Changing the internal geometric design of the ring was found to have minimal influence on the compression properties, thus the mechanical and release characteristics of the rings were largely decoupled. DISCUSSION/SIGNIFICANCE OF IMPACT: This is a novel approach to the design and fabrication of intravaginal rings for the treatment of infertility. The use of CAD and the decoupling of release from mechanical properties allows for us to move away from the one-size one-dose fits all approach to IVRs.

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Zhou, Guanghua, Wenting Wei, and Qinglong Liu. "Influence of Plastic Deformation on Microstructural Evolution of 100Cr6 Bearing Ring in Hot Ring Rolling." Materials 13, no. 19 (September 30, 2020): 4355. http://dx.doi.org/10.3390/ma13194355.

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The hot ring rolling technology as the crucial procedure for the manufacture of bearing rings plays an important role in determining the final microstructure of bearing rings. In this work, the influence of the hot ring rolling process on the microstructural evolution of 100Cr6 bearing rings was investigated using a three-dimensional (3D) numerical model and microstructural characterization. It was found that the significant microstructural refinement occurs at the different regions of the rings. However, owing to the non-uniform plastic deformation of hot rolling, the refinement rate of grain size and decrease of pearlite lamellar spacing (PLS) also showed uniformity at different regions of the rings. Furthermore, the degree of grain refinement had been limited with the increase of rolling reduction. Due to the refined grain size and decreased PLS, the Vickers hardness increased with the increase of rolling reduction. Moreover, the Vickers hardness from the outer surface to the inner surface of the ring is asymmetrical u-shaped, which had the law of lower hardness in the center area and higher hardness on the surface.

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Huo, Feng, Tao Xu, Xin Hong Fan, and Meng Ting Wei. "Grading Ring Parameters' Design for Y-Type Insulator String of 1000kV AC Double-Circuit Transmission Line." Applied Mechanics and Materials 740 (March 2015): 420–23. http://dx.doi.org/10.4028/www.scientific.net/amm.740.420.

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Y-type insulator string has advantages of external insulation and reduction of corridor width. This paper establishes a 3D finite element model of Y-type composite insulator string of 1000 kV AC double-circuit transmission line, including tower, insulator, grading rings, phase conductors and other hardware fittings, the model is used to calculate electric field distribution of composite insulator and grading ring. Then the parameters of grading ring are optimized based on the electric field results. According to the results, the optimum parameters of the racetrack grading ring are R=700 mm, r=120 mm, H=200 mm. The results can give a reference for design of UHV AC Y-type insulator string.

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Wang, Min. "Friction Effect in Hot Rolling of Large Rings with Different Sizes." Advanced Materials Research 213 (February 2011): 487–91. http://dx.doi.org/10.4028/www.scientific.net/amr.213.487.

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For hot rolling of large rings, the friction between a ring and rolls plays an important role in maintaining the stable forming of the process and quality of ring parts. The reasonable range of friction coefficient is determined analytically based on the stable forming condition, and a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for the process is developed. The effect of friction on hot rolling of titanium alloy large rings with different sizes are explored, and the results obtained show that as friction coefficient increases, different rings have similar variation law: less metal flows to the axial direction of a ring and the spread distribution at the end plane of a ring becomes more uniform; the strain and temperature distributions tend to be less uniform; rolling force and rolling moment have little change.

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Wang, Min. "FE Analysis of Spread in Hot Rolling of Large Rings with Different Sizes." Advanced Materials Research 433-440 (January 2012): 558–62. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.558.

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How to effectively reduce spread is an important subject in the area of ring rolling. In the paper, a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for hot rolling of large rings is developed. The relationship between spread and the equivalent shape parameters of the deformation zone is discussed. Variations of spread with relative reduction Rr during hot rolling of titanium alloy large rings with different sizes are analyzed and compared using FE simulation. The main results reveal that (1) the spread in a ring exhibits an axisymmetric distribution after the first revolution of the ring. (2) the peak spread appears in the inside or outside layer of a ring, and the minimum spread is found in the middle layer. (2) as Rr increases, the spread increases and the end-plane quality of the ring reduces.

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Patel, Vijay K., and Harish Rajak. "Development of Structure Activity Correlation Model on Aroylindole Derivatives as Anticancer Agents." Letters in Drug Design & Discovery 15, no. 2 (January 30, 2018): 143–53. http://dx.doi.org/10.2174/1570180814666170823161751.

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Background: Aroylindole derivatives, the structural analogs of Combretastatin A-4 has been found to possess potent growth inhibitory activity on several cancer cell lines due to its excellent antitumor and antivascular activities. The aim of present research work is to identify lead and establish structure activity correlation of trimethoxyaroylindole derivatives, using integrated ligand and structure based computational approaches. Materials and Methods: A correlation between structure and biological activity was established using computational approaches i.e., structure activity correlation by pharmacophore and atom based 3D QSAR, molecular docking and energetic based pharmacophore mapping studies of trimethoxyaroylindole derivatives. Results and Discussion: The 3D-QSAR on trimethoxyaroylindole derivatives generated and showed best statistical result for CPHs AAARR.182 was validated by Q2 (0.6929), R2 (0.82). The Comp. 1 of the training set was employed as template for hydrogen bond donor, hydrophobic and hydrogen bond acceptor field prediction features and visualization of the 3D-QSAR model provides details of relationship between structure and biological activity of trimethoxyaroylindole derivatives. Pharmacophore model was developed by Phase and e-pharmacophore on comp. 1, the trimethoxy group with ring A, keto group, N-H group with ring B and ring C are pharmacophoric group important for the lead generation and coincide with various chemical features that may facilitate non-covalent binding between the ligand and its target receptor. Molecular docking studies showed critical interactions between Cys241, Val318 and meta, para-methoxy group at ring A while and Thr179 and NH of indole (distance 3.5 Å). The para position of trimethoxyphenyl ring bind to SH group of CYS 241 receptor molecule via hydrogen bond. Conclusion: The lead identification and establish structure activity correlation of trimethoxyaroylindole derivatives, were performed using integrated ligand and structure based computational approaches i.e., atom based 3D QSAR and pharmacophore study, molecular docking, energetic based pharmacophore mapping studies showed promising results. The outcomes of present studies could be utilized for the design of novel aroylindole derivatives including its lead optimization as potential anticancer agent.

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Anjami, Nassir, and Ali Basti. "Investigation on Constant and Variable Feed Speeds Effects in Ring Rolling Process Using 3D FEM." Advanced Materials Research 264-265 (June 2011): 1776–81. http://dx.doi.org/10.4028/www.scientific.net/amr.264-265.1776.

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Although cold ring rolling (CRR) process is largely used in the manufacturing of profiled rings like bearing races, research on this purpose has been scant. In this study, based on a validated finite element (FE) model, CRR process is simulated regarding the variable and constant feed speeds of the mandrel roll which lead to constant and variable values of the ring's diameter growth rates respectively using a 3D rigid-plastic finite element method (FEM). Major technological problems involved in the process including plastic deformation behavior, strain distribution and its uniformity, Cockcroft and Latham damage field and final outer diameter of ring are fully investigated. The results of simulations would provide a good basis for process control especially feed speed controlled mills and guiding the design and optimization of both cold and hot ring rolling process.

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Shao, Xue Jiao, Lian Gang Zheng, Li Ping Zhang, and Xiao Long Fu. "Elastic and Plastic Analysis of O-Ring Seal for Reactor Pressure Vessel." Key Engineering Materials 725 (December 2016): 339–44. http://dx.doi.org/10.4028/www.scientific.net/kem.725.339.

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The elasto-plastic analysis for Reactor Pressure Vessel seal is necessary because of nuclear safety is actively demanded. The existed work based on simplified way to simulate the seal ring, such as uniform stress, spring elements, is too conservative. Therefore, it is necessary to simulate seal ring using 3D solid model considering the elasto-plastc deformation. In this paper, the two-dimensional model is adopted to simulate the compressing and springback character of inconel 718 O-ring using nonlinear isotropic hardening constitutive model and contact algorithm. The simulation approach and constitutive model are validated according to the deformation of seal ring using ANSYS. The seal analysis for reactor pressure vessel is achieved by considering complex loads, such as bolt pre-tightening force and temperature/pressure transient with the usage of an elasto-plastic constitutive model. It is found that the deformation of seal ring obtained by finite element is close to true value. The application of 3D solid model can reduce excessive conservatism effectively and improve the precision of seal analysis compare to the simplified method.

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Lim, Jae Hong, Heean Shin, Dong Ah Shin, Dae Hyun Kim, Suk Ho Sohn, Jae Woong Choi, Sungkyu Cho, Hee Chan Kim, and Ho Young Hwang. "Suture tie-down forces and cyclic contractile forces after an undersized tricuspid annuloplasty using a 3-dimensional rigid ring in an ovine model." European Journal of Cardio-Thoracic Surgery 60, no. 2 (March 31, 2021): 411–17. http://dx.doi.org/10.1093/ejcts/ezab131.

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Abstract OBJECTIVES This study was conducted to measure suture tie-down forces and evaluate cyclic contractile forces (CCFs) in beating hearts after undersized 3-dimensional (3D) rigid-ring tricuspid valve annuloplasty (TAP). METHODS Eight force transducers were attached to the 3D rigid TAP ring. Segments 1 to 8 were attached from the mid-septal to anterior-septal commissural area in a counterclockwise order. Two-sizes-down ring TAPs were performed in 6 sheep. Tie-down forces and CCF were recorded and analysed at the 8 annular segments and at 3 levels of peak right ventricular pressure (RVP: 30, 50 and 70 mmHg). RESULTS The overall average tie-down forces and CCF were 4.34 ± 2.26 newtons (N) and 0.23 ± 0.09 N, respectively. The CCF at an RVP of 30 mmHg were higher at 3 commissural areas (segments 3, 5 and 8) than at the other segments. The increases in the CCF following changes in the RVP were statistically significant only at the 3 commissural areas (P = 0.012). However, mean CCFs remained low at all annular positions (ranges of average CCF = 0.06–0.46 N). CONCLUSIONS The risk of suture dehiscence after down-sized 3D rigid-ring TAP might be minimal because the absolute forces remained low in all annular positions even in the condition of high RVP. However, careful suturing in the septal annular area and commissures is necessary to prevent an annular tear during a down-sized 3D rigid-ring TAP.

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Chen, Guo Qiang, Jian Ping Tan, Xian Wang, and Hui Chen. "3D Nonlinear Contact FEM Analysis of U-Ring Seal Structure." Advanced Materials Research 510 (April 2012): 660–66. http://dx.doi.org/10.4028/www.scientific.net/amr.510.660.

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The U-ring reciprocating seal structure with high pressure was taken as research object; the nonlinear contact characteristics and failure mechanism of U-ring seal were analyzed. Finite element model was build through segmentation and sweep methods, Mooney-Rivlin model was selected to characterize the rubber material, the Generalized Lagrange Multiplier Method were designed as contact algorithm. Based on LS-DYNA software, the 3D nonlinear dynamic simulations of U-ring seal structure were realized under different conditions. The results shows that the maximum contact stress steady increased with the growth of medium pressure, relative velocity, and friction coefficient, the top of inner lip and the circle of bottom hole were the main sites of contact stress concentrated on, the reverse velocity of valve stem is the main factor impact too large contact stress and seal damage. The simulation conclusions were verified by comparing the characteristics of actual seal failure.

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Vallecchi, Andrea, Ekaterina Shamonina, and Christopher J. Stevens. "Analytical model of the fundamental mode of 3D square split ring resonators." Journal of Applied Physics 125, no. 1 (January 7, 2019): 014901. http://dx.doi.org/10.1063/1.5053482.

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Qin, Zheng, Ji Jia, Tian-Tian Li, and Jiang Lu. "Extracting 2D Projection Contour from 3D Model Using Ring-Relationship-Based Method." Information Technology Journal 6, no. 6 (August 1, 2007): 914–18. http://dx.doi.org/10.3923/itj.2007.914.918.

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Huang, Si, Jing He, Xueqian Wang, and Guangqi Qiu. "Theoretical Model for the Performance of Liquid Ring Pump Based on the Actual Operating Cycle." International Journal of Rotating Machinery 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/3617321.

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Liquid ring pump is widely applied in many industry fields due to the advantages of isothermal compression process, simple structure, and liquid-sealing. Based on the actual operating cycle of “suction-compression-discharge-expansion,” a universal theoretical model for performance of liquid ring pump was established in this study, to solve the problem that the theoretical models deviated from the actual performance in operating cycle. With the major geometric parameters and operating conditions of a liquid ring pump, the performance parameters such as the actual capacity for suction and discharge, shaft power, and global efficiency can be conveniently predicted by the proposed theoretical model, without the limitation of empiric range, performance data, or the detailed 3D geometry of pumps. The proposed theoretical model was verified by experimental performances of liquid ring pumps and could provide a feasible tool for the application of liquid ring pump.

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Zhao, Jia, and Qi Wang. "A 3D Multi-Phase Hydrodynamic Model for Cytokinesis of Eukaryotic Cells." Communications in Computational Physics 19, no. 3 (March 2016): 663–81. http://dx.doi.org/10.4208/cicp.181014.140715a.

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AbstractIn the late stage of the mitotic cycle of eukaryotic cells, cytokinesis ensues during which a parent cell replicates its nucleus with the necessary genetical substances (i.e., DNAs and chromosomes) and splits into two similar offspring cells. This mitotic process involves complex chemical, biophysical andmechanical processes whose details are just beginning to be unfolded experimentally. In this paper, we propose a full 3-D hydrodynamical model using a phase field approach to study the cellular morphological change during cytokinesis. In this model, the force along the contracting ring induced by remodeling of actin-myosin filament on cell cortex layer at the division plane of the parent cell during cytokinesis, is approximated using a proxy force anchored on the newly formed nuclei. The symmetric or asymmetric cell division is simulated numerically with the model. Our numerical results show that the location of the division plane and the contracting force along the cytokinetic ring on the division plane are essential for the cell division. In addition, our numerical study also shows that, during cytokinesis, surface tension of the cell membrane also contributes to this process by retaining the morphological integrity of the offspring cells. This model and the accompanying numerical simulation tool provide a solid framework to build upon with more sophisticated whole cell models to probe the cell mitotic process.

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Kundera, Czesław, and Jerzy Bochnia. "Investigating the stress relaxation of photopolymer O-ring seal models." Rapid Prototyping Journal 20, no. 6 (October 20, 2014): 533–40. http://dx.doi.org/10.1108/rpj-04-2013-0043.

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Purpose – This paper aims to investigate the suitability of additive manufacturing to produce O-ring seals. Design/methodology/approach – The O-rings were made by the PolyJet-Matrix technology using four different digital materials and then tested for relaxation properties under static and dynamic (sliding) conditions. The approximation of the relaxation curves involved modelling with a Prony series. Findings – The PolyJet-Matrix technology offers new opportunities to model elastomeric elements, with examples being the O-rings produced and tested for their relaxation properties. Describing the behaviour of the particular materials fabricated with this technology by using relaxation functions will extend the knowledge base on digital materials. Research limitations/implications – The four types of photopolymers used in the experiment differed in viscoelastic properties. The analysis of the stress relaxation of the O-ring models was performed at four different step displacements of the loading element. Practical implications – The test results may be useful for the design of O-ring seals made of new elastomeric materials. The relaxation properties of the O-rings made of such materials can be applied to analyse the dynamics of seals, for instance, face seals. Originality/value – The originality of the work lies in the use of digital materials to design and produce elastomeric elements with different relaxation properties, which was confirmed by the test results. This paper presents results of a relaxation analysis for a ring model and the material that the ring is made of. It also discusses how 3D printing and digital materials can be applied in practice.

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Nguyen, Lam T., Matthew T. Swulius, Samya Aich, Mithilesh Mishra, and Grant J. Jensen. "Coarse-grained simulations of actomyosin rings point to a nodeless model involving both unipolar and bipolar myosins." Molecular Biology of the Cell 29, no. 11 (June 2018): 1318–31. http://dx.doi.org/10.1091/mbc.e17-12-0736.

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Cytokinesis in many eukaryotic cells is orchestrated by a contractile actomyosin ring. While many of the proteins involved are known, the mechanism of constriction remains unclear. Informed by the existing literature and new three-dimensional (3D) molecular details from electron cryotomography, here we develop 3D coarse-grained models of actin filaments, unipolar and bipolar myosins, actin cross-linkers, and membranes and simulate their interactions. Assuming that local force on the membrane results in inward growth of the cell wall, we explored a matrix of possible actomyosin configurations and found that node-based architectures like those presently described for ring assembly result in membrane puckers not seen in electron microscope images of real cells. Instead, the model that best matches data from fluorescence microscopy, electron cryotomography, and biochemical experiments is one in which actin filaments transmit force to the membrane through evenly distributed, membrane-attached, unipolar myosins, with bipolar myosins in the ring driving contraction. While at this point this model is only favored (not proven), the work highlights the power of coarse-grained biophysical simulations to compare complex mechanistic hypotheses.

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Tanaram, C., P. Phatharacorn, S. Chiangga, and P. P. Yupapin. "Analytical and simulation results of micro-ring resonator system using two eyes imaging model." International Journal of Scientific World 3, no. 2 (July 5, 2015): 227. http://dx.doi.org/10.14419/ijsw.v3i2.4881.

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<p>In this review article, the artificial vision model using the 3 cascaded conjugate mirrors system can be constructed, analyzed and simulated. A single 3D pixel (point) imaging construction is formed and obtained by using the conjugate mirror concept, where the large area of pixels can be potentially constructed and realized for large area application. This is a simulation work, where the software program is the finite difference time domain (FDTD) commercial program (Opti-wave). However, the used device parameters and materials can be fabricated and formed the artificial eyes for 3D artificial vision. Simulation result obtained has shown that the whispering gallery modes (WGMs) of radiation within the cascaded microring conjugate mirrors can be easily formed, and are coupled by the two nonlinear side rings, which can be potentially used for 3D imaging pixel construction applications by the two eyes construction model.</p>

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Yin, Changchun, and Greg Hodges. "3D animated visualization of EM diffusion for a frequency-domain helicopter EM system." GEOPHYSICS 72, no. 1 (January 2007): F1—F7. http://dx.doi.org/10.1190/1.2374706.

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The electromagnetic fields inside the earth are calculated by continuation downward of the electromagnetic (EM) solutions at the location of a frequency-domain helicopter electromagnetic (HEM) sensor. Models examined using the continuation approach include a layered isotropic and anisotropic earth. The finite-element approach is used to model 2D structures of a dipping contact or a dipping dike. By incorporating a time factor, we display the EM diffusion in the earth (change in direction and amplitude of the EM field through time) as 3D animated vectors or contours. The propagation of the EM smoke ring, influenced by the resistivity and structure of the earth, is apparent from the dynamic presentations. The current propagates downward and outward with time, becoming wider and more diffuse, and the phase varies with time, depth, and outward distance. The downward propagation of EM fields is slower in more conductive geology. In a layered isotropic earth, the current ring is symmetric with no vertical current flow for both vertical and horizontal dipole transmitters. In anisotropic or 2D structures; however, the current flow is significantly distorted resulting in vertical current flow and nonsymmetric smoke rings.

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Zhao, Yumin, W. Lin, and D. S. Qian. "Numerical Simulation and Experimental Research on the Rolling Process of Large-Scale Aluminum Ring." Materials Science Forum 628-629 (August 2009): 629–34. http://dx.doi.org/10.4028/www.scientific.net/msf.628-629.629.

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In the current study, a 3D elastic-plastic FE model for rolling of large-scale aluminum ring on high-voltage switch is developed under the ABAQUS software environment. Based on the 3D FE model, lots of simulation calculations have been carried out. Through simulation, the internal energy and kinetic energy histories during the process are obtained and the optimal mass scaling factor is determined reasonably. Additionally, the stress and stain field-variables and metal flow laws have also been analyzed in detail. The ring rolling experiment was carried out and the experimental results are in good agreement with the simulation ones. The research results provide powerful guidelines for the rolling process design of large-scale aluminum ring on high-voltage switch.

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Zhou, Ping Zhen, Li Wen Zhang, Sen Dong Gu, Hong Tao Duan, and Li Hong Teng. "Effects of Mandrel Structure on Ring Rolling Process for Large-Scale T-Sectioned Ring with Numerical Simulation." Advanced Materials Research 690-693 (May 2013): 2307–10. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.2307.

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The process parameters including the mandrel structure of radial-axial ring rolling is in close relationship with the forming defects such as over-high axial spread and the folding defect in the connecting part of the big and small ring. In this paper, a 3D rigid-plastic and coupled thermal-mechanical finite-element model (FEM) of radial-axial ring rolling for large-scale T-sectioned ring was developed using commercial software of DEFORM-3D. By changing the chamfer radius of mandrel's work roll, the effects of mandrel structure on the height of axial spread which considerably affects the stability of the ring rolling process were investigated. The folding defect was also simulated. The numerical simulation results showed that with the decrement of the chamfer radius r, the metal increasingly accumulated in the big ring and the axial spread height increased. Consequently, the ring rolling process became unstable. Also, the folding angle augmented.

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Guo, L. G., He Yang, Mei Zhan, Heng Li, and L. Y. Li. "Simulation for Guide Roll in 3D-FE Analysis of Cold Ring Rolling." Materials Science Forum 471-472 (December 2004): 760–64. http://dx.doi.org/10.4028/www.scientific.net/msf.471-472.760.

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A simple and efficient method has been proposed in order to determine the dynamic speed boundary condition caused by the guide rolls for developing the 3D-FE model of cold ring rolling process rapidly. The concept of the motion track of guide rolls has been put forward firstly and an optimal motion track and track type are given by simulation. Meanwhile, an effect of the guide rolls on the ring tilting and ring circularity was simulated and analyzed. The result shows that the simulation results are in good agreement with experiment results from the literature.

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Kebriaei, Reza, Jan Frischkorn, Stefanie Reese, Heiko Moll, Werner Theisen, Tobias Husmann, and Horst Meier. "Coupled Thermo-Mechanical Analysis of Process-Integrated Powder Coating by Means of Hot Rolling." Key Engineering Materials 504-506 (February 2012): 193–98. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.193.

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In this paper, a new hybrid production technique is presented. It exploits the advantage of high temperatures and high forces in the ring rolling process. This manufacturing technique is not only suitable to increase the ring’s diameter but also to apply and compact powder metallurgical multi-functional coatings onto solid substrate rings with the same process. In order to design this new process parameterized 2D and 3D FE models are created in ABAQUS/EXPLICIT on the basis of a viscoplastic material model formulation. The control capability of the conventional control mechanisms are based on the assumption of volume consistency. However, this assumption is not well applicable for a ring furnished by multi-functional surfaces with non-isochoric plastic deformation behavior. Therefore, this paper deals with the implementation of a new control mechanism. Finally the paper is concluded with the integration of heat treatment of the rolled ring into the subsequent cooling process.

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Planelles, Josep, and Juan I. Climente. "Far-Infrared Absorption of Self-Assembled Semiconductor Rings." Collection of Czechoslovak Chemical Communications 70, no. 5 (2005): 605–20. http://dx.doi.org/10.1135/cccc20050605.

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A theoretical description of far-infrared spectroscopy experiments on self-assembled quantum rings in a magnetic field [Lorke A. et al.: Phys. Rev. Lett. 2000, 84, 2223] is reported which, for the first time, accounts for the full set of experimental resonances. In calculations a 3D effective-mass model with a realistic finite step-like confinement potential, including strain and Coulomb effects is used. A bimodal distribution of ring sizes is assumed.

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Qi, Liang Tao, Bao Shou Sun, and Xue Dao Shu. "Process Research on Cold Rolling of Gulley Ball Bearing Inner Ring." Advanced Materials Research 314-316 (August 2011): 477–81. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.477.

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3D model of 6006 gulley ball bearing inner ring is established in this paper. Based on the study of finite element numerical simulation on the cold rolling process of inner ring by Deform-3D software, the paper shows the influence of the feed rate of idle roller, rotational rate of driving roller as well as wide-diameter ratio on the rules of rolling forming of bearing inner ring. Through the research of numerical simulation, it is discovered that feed rate of idle roller and wide diameter ratio have a greater impact on the ring end surface quality larger than rotational rate of driving roller does. Thus, process parameters should be chosen reasonably according to mold parameters and material parameters, which will help improve the stability of the cold rolling process and the rolling production efficiency.

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Ahn, Tae Jun, and Yun Seop Yu. "Circuit Simulation Considering Electrical Coupling in Monolithic 3D Logics with Junctionless FETs." Micromachines 11, no. 10 (September 24, 2020): 887. http://dx.doi.org/10.3390/mi11100887.

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The junctionless field-effect transistor (JLFET) compact model using the model parameters extracted from the LETI-UTSOI (version 2.1) model was proposed to perform circuit simulation considering the electrical coupling between the stacked JLFETs of a monolithic 3D integrated circuit (M3DIC) composed of JLFETs (M3DIC-JLFET). We validated the model by extracting the model parameters and comparing the simulation results of the technology computer-aided design and the Synopsys HSPICE circuit simulator. The performance of the M3DIC-JLFET was compared with that of the M3DIC composed of MOSFETs (M3DIC-MOSFET). The performance of a fan-out-3 ring oscillator with M3DIC-JLFET varied by less than 3% compared to that with M3DIC-MOSFET. The performances of ring oscillators of M3DIC-JLFET and M3DIC-MOSFET were almost the same. We simulated the performances of M3DICs such as an inverter, a NAND, a NOR, a 2 × 1 multiplexer, and a D flip-flop. The overall performance of the M3DIC-MOSFET was slightly better than that of the M3DIC-JLFET.

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Brock, Christina, Romulus E. Lontis, Flemming H. Lundager, Peter Kunwald, Asbjørn M. Drewes, and Hans Gregersen. "Model for Electrical Field Distribution in the Human Esophagus during Stimulation with Patch and Ring Electrodes." Gastroenterology Research and Practice 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/562592.

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Introduction. Electrical stimulation is used in experimental human pain models. The aim was to develop a model that visualizes the distribution of electrical field in the esophagus close to ring and patch electrodes mounted on an esophageal catheter and to explain the obtained sensory responses.Methods. Electrical field distribution in esophageal layers (mucosa, muscle layers, and surrounding tissue) was computed using a finite element model based on a 3D model. Each layer was assigned different electrical properties. An electrical field exceeding 20 V/m was considered to activate the esophageal afferents.Results. The model output showed homogeneous and symmetrical field surrounding ring electrodes compared to a saddle-shaped field around patch electrodes. Increasing interelectrode distance enlarged the electrical field in muscle layer.Conclusion. Ring electrodes with 10 mm interelectrode distance seem optimal for future catheter designs. Though the model needs further validation, the results seem useful for electrode designs and understanding of electrical stimulation patterns.

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Ma, Qi, Lin Hua, and Dong Sheng Qian. "Coupled Thermo-Mechanical FEA of Three-Roll Cross Rolling Process for Rings with Small-Hole and Deep Groove." Advanced Materials Research 560-561 (August 2012): 846–52. http://dx.doi.org/10.4028/www.scientific.net/amr.560-561.846.

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Ring parts with small-hole and deep groove such as duplicate gear and double-side flange, are widely used in various engineering machineries. Three-roll cross rolling (TRCR) is a new advanced plastic forming technology for the processing of rings with small-hole and deep groove. In this paper, a 3D coupled thermo-mechanical FE model for TRCR of ring with small-hole and deep groove is established under ABAQUS software environment. By simulation and analysis, the evolution and distribution laws of strain and temperature in the forming process are revealed, and the effects of the key process parameters on the deformation uniformity are explored. The results provide valuable guideline for the technological parameter design and optimization.

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Giemza, Bolesław, Marek Domański, Maciej Deliś, and Dawid Kapica. "Tribological properties of 3D printed components." Journal of KONBiN 48, no. 1 (December 1, 2018): 447–63. http://dx.doi.org/10.2478/jok-2018-0066.

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Abstract Additive manufacturing technology is developing in many industries, including aviation, automotive and others. 3D printing offers new possibilities in the field of designing and manufacturing of machines and devices’ components. The paper presents the results of tribological investigations of components produced in FDM printing technology. The authors presented the evaluation of sliding properties of the model friction couple – block on ring type – of available thermoplastic polymers and polymers’ composites under dry friction conditions. The authors assessed the influence of material type and printed structure on resistance to motion of prepared samples.

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Yuan, Fang, Lingzhi Yue, Han Zhao, and Huifang Wu. "Study on the adsorption of polystyrene microplastics by three-dimensional reduced graphene oxide." Water Science and Technology 81, no. 10 (May 15, 2020): 2163–75. http://dx.doi.org/10.2166/wst.2020.269.

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Abstract In this paper, a study on the removal of imitated polystyrene (PS) microplastics in water was carried out based on the adsorption capacity of three-dimensional reduced graphene oxide (3D RGO). Scanning electron microscopy and X-ray diffractometry characterization showed that the freeze-dried 3D RGO formed a distinct porous spatial structure. Different experimental parameters, such as pH, ion concentration (C0), contact time (t), and temperature (T), were studied to investigate the PS microplastic adsorption performance of 3D RGO. The adsorption mechanism was mainly attributed to the strong π–π interaction between the carbon ring of 3D RGO and the benzene ring of PS microplastics. Sorption kinetic and isothermal data were obtained by the well-fitted Langmuir adsorption isotherm model and pseudo-second-order kinetic model. Furthermore, the result of thermodynamic analysis showed that the adsorption of PS microplastics was a spontaneous endothermic process. Under the optimal conditions of pH = 6, C0 = 600 mg/L, t = 120 min, and T = 26 °C, the maximum adsorption capacity of the prepared 3D RGO on PS microplastics was 617.28 mg/g. Furthermore, this method exhibited good feasibility in tap water and lake water.

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38

Bidone, Tamara C., Haosu Tang, and Dimitrios Vavylonis. "Dynamic Network Morphology and Tension Buildup in a 3D Model of Cytokinetic Ring Assembly." Biophysical Journal 107, no. 11 (December 2014): 2618–28. http://dx.doi.org/10.1016/j.bpj.2014.10.034.

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Zhang, Lei, and Xiukun Wang. "Numerical coffee-ring patterns with new interfacial schemes in 3D hybrid LB-LE model." Powder Technology 392 (November 2021): 130–40. http://dx.doi.org/10.1016/j.powtec.2021.07.012.

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Zhu, Juan, Long Qing Zou, and Shi Jie Han. "The Modeling of Rubber Sealing Ring of Fluid Dynamic Pressure and Finite Element Analysis about Stress Based on SolidWorks and ANSYS." Applied Mechanics and Materials 215-216 (November 2012): 1246–49. http://dx.doi.org/10.4028/www.scientific.net/amm.215-216.1246.

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Hydrodynamic seal ring is based on the hydrodynamic effect of rotary shaft seal, Kalsi sealing ring is the typical type of products, and the design of sealing lip adopts unique waveform structure. Based on geometry analysis of the sealing ring, the 3D model of the ring was established by using SolidWorks software, and then the model was introduced into finite element software ANSYS, which was used to analyse stress for the Kalsi of rubber sealing ring. Through the analysis of the stress of rubber ring, the position of the maximum stress value of the rubber seal in hydrodynamic pressure was wave crest (valley) in the edge of the wave side. When the pressure of seal was 10MPa, the maximum value of stress of rubber sealing was up to 6.54MPa.

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41

Xu, Hai Yong. "Numerical Analysis of Top Ring Beam for Foundation Pit." Applied Mechanics and Materials 166-169 (May 2012): 1137–40. http://dx.doi.org/10.4028/www.scientific.net/amm.166-169.1137.

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The research and application condition of top ring beam for the foundation pit engineering is introduced. A 3D finite element model of row piles and top ring beam is calculated and several major parameters of the beams are discussed. On the basic of the FEM results, a simplified method is proposed to calculate the equivalent stiffness of the beam in a typical design profile for practical engineering.

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42

Woraratsoontorn, Pattaraweerin, and Pitikhate Sooraksa. "Development of Tolerance Ring for Cleanliness in Assembly Process." Advanced Materials Research 677 (March 2013): 246–51. http://dx.doi.org/10.4028/www.scientific.net/amr.677.246.

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In arm hookup assembly process, the tolerance ring is commonly used for coupling a bearing cartridge to an arm hookup. This process often encounter cleanliness problem which is caused by metal scratch between the arm hookup and the tolerance ring. The main purpose is development the tolerance ring using finite element 3D model and validation of experimental result. The result shows that the simulation result corresponds to the experimental result, the vulnerable point effect less movement of the tolerance ring. Moreover, the cleanliness problem in process was eliminated also.

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Marinaro, Gianluca, Emma Frosina, Adolfo Senatore, Kim A. Stelson, and Yuhao Feng. "3D CFD numerical analysis of vane dynamic effects on the pressure ripple in a variable displacement vane pump." E3S Web of Conferences 197 (2020): 07001. http://dx.doi.org/10.1051/e3sconf/202019707001.

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A numerical three-dimensional CFD analysis of a variable displacement vane pump has been conducted, investigating the effects on the pressure ripple caused by the vane detaching from the pressure ring. The volume of the fluid over the vane tip has been re-meshed at every time step as a function of the forces acting on the bottom and the top of each vane. The numerical model has been developed using the commercial tool, Simerics MP+, including turbulence and cavitation models. The validation of the model has been done comparing numerical and experimental data. It has been observed that the detachment of the vane occurs during the transition zones when unwanted pressure spikes are generated by a nonoptimized valve plate design. The prediction of vane detachment is crucial for designing a quieter and more durable pump. Vane collision on the stator ring can be a source of noise producing premature wear of both components. Vane detachment from the stator ring has a large effect on pressure ripple even if the volumetric efficiency is only slightly influenced.

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44

Polamreddy, Prasanthi, Vinita Vishwakarma, and Manoj Kumar Mahto. "COMBINATORIAL PHARMACOPHORE MODELING AND ATOM BASED 3D QSAR STUDIES OF BENZOTHIADIAZINES AS HCV-NS5B INHIBITORS." International Journal of Pharmacy and Pharmaceutical Sciences 10, no. 3 (March 1, 2018): 43. http://dx.doi.org/10.22159/ijpps.2018v10i3.23734.

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Objective: The objective of the current study was to elucidate the 3D pharmacophoric features of benzothiadiazine derivatives that are crucial for inhibiting Hepatitis C virus (HCV) Non-structural protein 5B (NS5B) and quantifying the features by building an atom based 3D quantitative structure-activity relationship (3D QSAR) model.Methods: Generation of QSAR model was carried out using PHASE 3.3.Results: A five-point pharmacophore model with two hydrogen bond acceptors, one negative ionization potential and two aromatic rings (AANRR) was found to be common among a maximum number of benzothiadiazine based NS5B inhibitors. A statistically significant 3D QSAR model was obtained from AANRR.6 which had correlation-coefficient (R2) value of 0.924, cross-validated correlation-coefficient (Q2) of 0.774, high Fisher ratio of 138 and low root mean square standard error (RMSE=0.29). There is another parameter, Pearson’s R, its value emphasizes correlation between predicted and observed activities of the test set. For the current model, Pearson’s R-value is 0.90, hence underlining the good quality of the model. The present study suggests that nitrogen atom of benzothiadiazine sulfamide ring, oxyacetamide group attached to C7 carbon of benzothiadiazine and sulfonamide oxygens are crucial for NS5B inhibitory activity. Prediction of activities of hit drugs generated in earlier research suggests that Aprepitant (Phase predicted activity: 6.9) could be a potential NS5B inhibitor.Conclusion: This 3D QSAR model developed was statistically good and can be used to predict the activities of newly designed NS5B inhibitors and virtual screening as well. Predict the activities of newly designed NS5B inhibitors and virtual screening as well.

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45

Li, Hong Wei, He Yang, Zhi Chao Sun, M. Wang, and Lan Yun Li. "Simulation of Cold Ring Rolling Based on Rate Dependent Crystal Plasticity." Materials Science Forum 561-565 (October 2007): 1813–17. http://dx.doi.org/10.4028/www.scientific.net/msf.561-565.1813.

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Material behaviors of anisotropy and rate sensitivity affect cold ring rolling greatly. So, a self-developed incremental model of rate dependent crystal plasticity (RDCP) is utilized to forecast the deformation characteristics of this forming process based on a 3D FE model under ABAQUS/Explicit environment. The results show that the model of RDCP captures material behaviors of anisotropy and rate sensitivity better in this forming process by the comparison with the model of J2 plasticity; with the decrease of rate sensitivity coefficient, the forming process becomes more unstable with smaller rolling force and growth in ring radial direction; with the increase of feed rate of idle roll, the deformation of ring becomes more even while the rolling force becomes larger.

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46

Syed, Khajamohiddin, Aleksey Porollo, Ying Wai Lam, Paul E. Grimmett, and Jagjit S. Yadav. "CYP63A2, a Catalytically Versatile Fungal P450 Monooxygenase Capable of Oxidizing Higher-Molecular-Weight Polycyclic Aromatic Hydrocarbons, Alkylphenols, and Alkanes." Applied and Environmental Microbiology 79, no. 8 (February 15, 2013): 2692–702. http://dx.doi.org/10.1128/aem.03767-12.

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ABSTRACTCytochrome P450 monooxygenases (P450s) are known to oxidize hydrocarbons, albeit with limited substrate specificity across classes of these compounds. Here we report a P450 monooxygenase (CYP63A2) from the model ligninolytic white rot fungusPhanerochaete chrysosporiumthat was found to possess a broad oxidizing capability toward structurally diverse hydrocarbons belonging to mutagenic/carcinogenic fused-ring higher-molecular-weight polycyclic aromatic hydrocarbons (HMW-PAHs), endocrine-disrupting long-chain alkylphenols (APs), and crude oil aliphatic hydrocarbonn-alkanes. A homology-based three-dimensional (3D) model revealed the presence of an extraordinarily large active-site cavity in CYP63A2 compared to the mammalian PAH-oxidizing (CYP3A4, CYP1A2, and CYP1B1) and bacterial aliphatic-hydrocarbon-oxidizing (CYP101D and CYP102A1) P450s. This structural feature in conjunction with ligand docking simulations suggested potential versatility of the enzyme. Experimental characterization using recombinantly expressed CYP63A2 revealed its ability to oxidize HMW-PAHs of various ring sizes, including 4 rings (pyrene and fluoranthene), 5 rings [benzo(a)pyrene], and 6 rings [benzo(ghi)perylene], with the highest enzymatic activity being toward the 5-ring PAH followed by the 4-ring and 6-ring PAHs, in that order. Recombinant CYP63A2 activity yielded monohydroxylated PAH metabolites. The enzyme was found to also act as an alkane ω-hydroxylase that oxidizedn-alkanes with various chain lengths (C9to C12and C15to C19), as well as alkyl side chains (C3to C9) in alkylphenols (APs). CYP63A2 showed preferential oxidation of long-chain APs and alkanes. To our knowledge, this is the first P450 identified from any of the biological kingdoms that possesses such broad substrate specificity toward structurally diverse xenobiotics (PAHs, APs, and alkanes), making it a potent enzyme biocatalyst candidate to handle mixed pollution (e.g., crude oil spills).

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47

Hardy, Stuart. "The Internal Structural Evolution of Calderas: Results from 3D Discrete Element Simulations." Geosciences 9, no. 10 (September 26, 2019): 419. http://dx.doi.org/10.3390/geosciences9100419.

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The structural evolution of calderas is a key issue in volcanology and has profound implications for hazard analysis and the exploitation of geothermal energy and hydrothermal ores. However, their internal geometry at depth and the detailed fault and fracture distribution are unclear and debated. In order to better constrain the internal structural evolution of calderas, I have developed a 3D discrete element model of a frictional cover undergoing piston-like subsidence at its base, simulating magma chamber deflation and cover collapse. I examine two piston geometries, simulating magma chambers with roofs that are circular and rectangular in plan view, to investigate patterns of faulting and subsidence in three dimensions. In both models a complex arrangement of normal and reverse faults accommodates deeper subsidence at higher structural levels. Bell- to cone-shaped, outward-dipping ring faults are consistently the first structures to develop; these faults propagate upwards from the piston edges towards the surface. Later caldera growth is mainly the result of movement on vertical, or steeply inward-dipping, normal ring faults which enclose the earlier reverse faults. As a result, all calderas widen, in terms of their surface expression, with time. The final stage of caldera development includes significant collapse of the caldera walls and transport of this material towards the caldera center. The results confirm that the evolutionary patterns/stages proposed from 2D numerical and analogue models can be generalized to three dimensions, although significant differences between long- and short-axis geometries do occur when the piston is elongate. Compared to 2D simulations, however, 3D results show the geometric complexity of ring faulting, with variations in strain and fault activity at various stages of development demonstrating that often a simple, continuous ring fault structure is not developed.

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48

Abousleiman, V., P. Velex, and S. Becquerelle. "Modeling of Spur and Helical Gear Planetary Drives With Flexible Ring Gears and Planet Carriers." Journal of Mechanical Design 129, no. 1 (February 22, 2006): 95–106. http://dx.doi.org/10.1115/1.2359468.

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A model is presented which enables the simulation of the three-dimensional static and dynamic behavior of planetary/epicyclic spur and helical gears with deformable parts. The contributions of the deflections of the ring gear and the carrier are introduced via substructures derived from 3D finite element models. Based on a modal condensation technique, internal gear elements are defined by connecting the ring-gear substructure and a planet lumped parameter model via elastic foundations which account for tooth contacts. Discrete mesh stiffness and equivalent normal deviations are introduced along the contact lines, and their values are recalculated as the mating flank positions vary with time. A constraint mode substructuring technique is used to simulate the planet carrier as a superelement which is connected to the planet center. Planetary/epicyclic gear models are completed by assembling lumped parameter sun gear/planet elements along with shaft elements, lumped stiffness, masses and inertias. The corresponding equations of motion are solved by combining a time-step integration scheme and a contact algorithm for all simultaneous meshes. Several quasistatic and dynamic results are given which illustrate the potential of the proposed hybrid model and the interest of taking into account ring gear and carrier deflections.

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Yedan, Li, Pang Kunjing, Jiang Yong, and Wang Hao. "The Echocardiographic Analysis of Aortic Root Structure Based on Gaussian Process and Hidden Space Segmentation." Journal of Medical Imaging and Health Informatics 9, no. 6 (August 1, 2019): 1262–66. http://dx.doi.org/10.1166/jmihi.2019.2727.

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The significance of automatic measurement of transesophageal three-dimensional echocardiography in the selection of valve models for transcatheter aortic valve replacement (TAVR) was discussed. Selecting the imaginary TAVR valve model according to the aforementioned 2D-TTE, 2D-TEE, 3D-TEE esie valves' semi-automatic monitoring method and the monitoring data of the aortic valve ring obtained by the MDCT valve valve. The model selection criteria are based on the user manual taking SAPIEN 3 valves, Core Valve valves and Lotus valves as examples. The comparison of model selection results is carried out by using hidden space segmentation of Gauss process. The same result as that of the MDCT valve can be achieved when the TAVR valve model is selected according to the automatic measurement result of theesie Valves 3D-TEE.

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50

Wang, Min, and Chun Zhang. "Rolling Force in Hot Rolling of Large Rings." Advanced Materials Research 314-316 (August 2011): 539–42. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.539.

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For hot rolling of large rings, determination of rolling force plays an important role in designing, choosing and optimizing of processing plan and rolling mill. The average shape parameter of the deformation zone of ring rolling is presented, and a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for the process is developed. The effects of processing parameters on rolling force during hot rolling of titanium alloy large rings with different sizes are explored and the results obtained show that different rings follow a similar trend: increasing the relative reduction or rotational speed of the driver roll, or decreasing the feed rate of the idle roll is beneficial to a reduction in rolling force.

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Journal articles on the topic '3D ring model'

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