Journal articles: 'Geometrical configuration'

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Destainville, N., R. Mosseri, and F. Bailly. "Configurational entropy in random tilings: A geometrical analysis in configuration space." Mathematical and Computer Modelling 26, no. 8-10 (October 1997): 313–14. http://dx.doi.org/10.1016/s0895-7177(97)00214-8.

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Chen, F.-C. "On the structural configuration synthesis and geometry of machining centres." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 215, no. 6 (June 1, 2001): 641–52. http://dx.doi.org/10.1243/0954406011524018.

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The purpose of this paper is to synthesize all possible structural configurations of three-, four- and five-axis machining centres and to investigate the geometrical characteristics of five-axis machining centres. Based on the definition of coordinate systems and the configuration code of machine tools, it was found that there are 24, 96 and 288 feasible configurations for three-, four- and five-axis machining centres respectively. The geometric characteristics of five-axis machining centres were analysed and summarized by using the method of coordinate transformation. The results of this paper are beneficial to engineers in the design and evaluation of machining centres.

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Azlan Musa, Mohd, Mohammad Fadhli Ahmad, Nor Aieni Mokhtar, and Ahmad Jusoh. "Investigation of Wave Overtopping from Various Geometrical Configurations of Coastal Breakwater Ramps." International Journal of Engineering & Technology 7, no. 3.28 (August 17, 2018): 24. http://dx.doi.org/10.14419/ijet.v7i3.28.20959.

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Breakwater is often required for erosion protection. The effectiveness of breakwater structure as a coastal defence could be determined through overtopping wave surpass onto its crest freeboard structure. The common design practice of breakwater structure is using a linear ramp configuration. There is still a limited knowledge on the contribution of various configuration ramps shape into breakwater efficiency. Thus, this study attempts to investigate a few other's configuration of ramp geometries through overtopping discharge rate performance and identified its relationships with the crest freeboard. Three configurations of ramp geometries (convex, concave and cubic) have been investigated using numerical simulation of CFD-Flow 3D software. The result indicates that, there are significant influences of ramp configuration parameters on the overtopping rate and the highest overtopping rate is contributed from cubic shape ramp geometry. It is recommended that the detail study on cubic ramp shape geometry for determining its capability in increasing overtopping rate.

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De Queiroz, João Pedro T. P., Marcelo L. Cunha, Ana Pavlovic, Luiz Alberto O. Rocha, Elizaldo D. Dos Santos, Grégori da S. Troina, and Liércio A. Isoldi. "Geometric Evaluation of Stiffened Steel Plates Subjected to Transverse Loading for Naval and Offshore Applications." Journal of Marine Science and Engineering 7, no. 1 (January 7, 2019): 7. http://dx.doi.org/10.3390/jmse7010007.

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This work searched for the optimal geometrical configuration of simply supported stiffened plates subjected to a transverse and uniformly distributed load. From a non-stiffened reference plate, different geometrical configurations of stiffened plates, with the same volume as the reference plate, were defined through the constructal design method. Thus, applying the exhaustive search technique and using the ANSYS software, the mechanical behaviors of all the suggested stiffened plates were compared to each other to find the geometrical configuration that provided the minimum deflection in the plate’s center when subjected to this loading. The optimum geometrical configuration of stiffeners is presented at the end of this work, allowing a reduction of 98.57% for the central deflection of the stiffened plate if compared to the reference plate. Furthermore, power equations were adjusted to describe the deflections for each combination of longitudinal and transverse stiffeners as a function of the ratio between the height and the thickness of the stiffeners. Finally, a unique equation for determining the central deflections of the studied stiffened plates based only on the number of longitudinal stiffeners without significantly losing accuracy has been proposed.

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Dijksman, E. A. "Assembling Complete Pole Configurations for (Over)Constrained Planar Mechanisms." Journal of Mechanical Design 116, no. 1 (March 1, 1994): 215–25. http://dx.doi.org/10.1115/1.2919350.

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The complete pole configuration of a planar n-link mechanism having one instantaneous degree of mobility, possesses (3n−4)/2 independent poles determining (n−2)2/2 remaining poles of the configuration. The dependency is demonstrated through Desargues’ Theorem and her generalizations. Simultaneously, pole configurations have been “elated” into three-dimensional point-lattices intersected by a plane. The insight obtained in these configurations allows the designer to find clues in building overconstrained linkage mechanisms meeting certain geometrical properties.

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SEGEV, REUVEN. "A GEOMETRICAL FRAMEWORK FOR THE STATICS OF MATERIALS WITH MICROSTRUCTURE." Mathematical Models and Methods in Applied Sciences 04, no. 06 (December 1994): 871–97. http://dx.doi.org/10.1142/s0218202594000480.

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A geometrical framework for the formulations of the invariant mechanical theories of materials with microstructure is presented. The suggested framework is based on the construction of an infinite-dimensional manifold containing the configurations of the body. Each configuration includes both the macro- and the micro-states of the body. The notions of forces, stresses, balance laws and latent microstructure are discussed. Liquid crystals are used as an example.

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KUPRIKOV, Mikhail Yu, and Leonid V. MARKIN. "Methods of the automated aircraft configuration." INCAS BULLETIN 11, S (August 1, 2019): 125–34. http://dx.doi.org/10.13111/2066-8201.2019.11.s.12.

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Aircraft are great and comprehensive technical systems, which are characterised by the great configuration density. This article presents formation of the geometrical conceptual design of the aircraft on the basis of the formal heuristic procedures within the framework of the infrastructural constraints. In addition, this article includes description of influence of the aerodynamic configuration and the volume-weight configuration upon formation of the geometrical conceptual design of the aircraft, as well as description of other mass/inertia characteristics of the aggregates, which are to be installed within the specific aircraft. This article also states that in the case of the "very strict" infrastructural constraints, it is necessary to solve "the inverse" problem of configuration, that is the problem, where initial data for formation of the geometrical conceptual design of the aircraft are determined by the necessary configuration space, which is determined by the infrastructural constraints. The article presents the project problem (in aggregate) of finding rational values for parameters of the geometrical conceptual design of the aircraft as the problem of the multiple criteria discrete optimisation. This article states that it is possible to formulate this problem as the search of the vector of structural parameters (that is, search of the multitude of the admissible alternatives of the drawing and designing solutions).

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Ali, Nicholas, and Kamran Behdinan. "OPTIMAL GEOMETRICAL DESIGN OF AIRCRAFT USING GENETIC ALGORITHMS." Transactions of the Canadian Society for Mechanical Engineering 26, no. 4 (December 2003): 373–88. http://dx.doi.org/10.1139/tcsme-2002-0022.

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With the advent of computers and search and optimization tools such as the genetic algorithm, the ability to manipulate numerous aircraft design parameters in a reasonable amount of time is feasible. From this angle, the lengthy time and effort spent creating and integrating aerodynamics codes, sizing routines, and performance modules, can be mitigated by the use of a genetic algorithm. Consequently, a genetic algorithm has been created and employed as a cost effective tool to explore possible aircraft geometries in the conceptual design process of the aircraft. A program has been developed to address most aspects of aircraft design such as aircraft sizing and configuration, performance, and propulsion, to name a few. These codes have been integrated into a genetic algorithm, which performs the task of searching and optimizing. The adaptive penalty method has been employed to handle all constraints imposed on the design. In addition, adjustments for varying degrees of selection and crossover intensities and types have been studied. A design study has also been carried out to compare an existing aircraft shape with the genetic algorithm optimized aircraft shape and configuration. Results indicate that the genetic algorithm is a powerful multi-disciplinary optimization and search tool, capable of simultaneously managing and varying numerous aircraft design parameters. Moreover, the genetic algorithm is capable of finding aircraft geometries and configurations that are both efficient and cost effective.

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Jirout, Tomáš, and Dita Jiroutová. "Application of Theoretical and Experimental Findings for Optimization of Mixing Processes and Equipment." Processes 8, no. 8 (August 8, 2020): 955. http://dx.doi.org/10.3390/pr8080955.

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The homogenization of the agitated batch and ensuring the suspension of particles are the most frequently encountered requirements in terms of mixing applications. These operations are affected by the flow of the agitated batch. The geometrical parameters of the mixing system, especially the shape of the agitator blade, affect flow and circulation in the agitated batch. The present work provides a general description of the most common processes in the agitated batch (blending and particle suspension), hydrodynamic parameters (flow in agitated batches, pumping and circulation capacity of impellers) and the geometrical configurations of the mixing equipment (shape of vessel, baffle and impeller, and their mutual arrangement) that influence the process. The dimensionless process characteristics of the agitator were derived by theoretical analysis. These characteristics were applied to evaluate an extensive set of experimental data with various geometric configurations of the mixing equipment. This study shows how the flow in the agitated batch, caused by the pumping and circulating effects of the agitators, affects the parameters and energy efficiency of these processes, depending on the geometric configuration of the mixing equipment. Moreover, the benefits of the hydrofoil impellers used for these mixing processes are presented.

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BUENO, J. R., and D. D. LORIGGIO. "Analysis of second order effects: case study." Revista IBRACON de Estruturas e Materiais 9, no. 4 (August 2016): 494–501. http://dx.doi.org/10.1590/s1983-41952016000400002.

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Abstract This paper presents a nonlinear static analysis of a reinforced concrete plane frame. It has as main objective is to realize a global stability verification of a plane frame, by using geometric stiffness matrix. In order to obtain first and second order combined effects, equilibrium and kinematic relations were studied in the deformed geometric configuration. These results were obtained by using geometric stiffness matrix and multiplying horizontal forces by Gamma-Z coefficient. Both procedures disclosed very similar results in the study, indicating that Gamma-Z can be used to study equilibrium and kinematic relations in deformed geometrical configuration of the structure.

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LIANG, J. Q. "QUANTUM ANHOLONOMY AND GEOMETRICAL PHASE INTERFERENCE." International Journal of Modern Physics A 07, no. 20 (August 10, 1992): 4747–55. http://dx.doi.org/10.1142/s0217751x92002143.

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Dragged wave functions are suggested for description of quantum geometrical phase interference. It is shown that the nontrivial topology of configuration space and Wess-Zumino type interactions are responsible for the nontrivial quantum anholonomy. The Aharonov-Bohm and Aharonov-Casher effects are unified under our framework.

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Lelyukhin, Vladimir Egorovich, and Olga Valeryevna Kolesnikova. "Geometry of real objects in shipbuilding and ship repair." Vestnik of Astrakhan State Technical University. Series: Marine engineering and technologies 2020, no. 1 (February 17, 2020): 31–44. http://dx.doi.org/10.24143/2073-1574-2020-1-31-44.

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The article considers the modern engineering practice of designing and manufacturing that uses various analytical and graphic forms representing geometric objects. Both of these forms are characterized by the presence of two problems in terms of production practice: 1 - tools of modern geometry cannot operate with non-ideal forms and configurations of material objects; 2 - lack of methods and tools for describing patterns of generating geometric objects, from production lines to the structure that characterizes the relative location of surfaces. The generalized provisions of the geometry of non-ideal objects theoretically justified for formal synthesis and their elements have been presented, which avoids problems of geometric configuration in the practice of designing and developing manufacturing technologies in shipbuilding and ship repair. A special toolkit based on discrete mathematics is proposed for the formal description of the geometric configuration of non-ideal objects. The principles of geometry of real objects describe the structural-parametric representation of objects in a six-dimensional space that is defined by linear and angular vectors. The concepts of linear and angular vectors are analyzed. It has been stated that the presence of an angular vector simplifies the perception and makes easier calculating the processes of geometric transformations. A geometrical object refers to a closed subspace bounded by a single surface, a set of mating or intersecting surfaces. The examples of the real plane deviations from its reference, location of the planes for creating the ideal geometric configuration, variants of real images, forming the basis for six-dimensional space, structure of geometric configurations have been illustrated. It has been found that any specific part acting as a geometric object can be represented by a set of surfaces and the structure of their relationships, which contributes to the correctness of its manufacture. The use of six-dimensional space allows to describe the spatial geometric configurations of parts of various mechanisms with mathematical accuracy.

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Massa, Enrico, Stefano Vignolo, Roberto Cianci, and Sante Carloni. "A new geometrical look at Ostrogradsky’s procedure." International Journal of Geometric Methods in Modern Physics 15, no. 08 (June 22, 2018): 1850128. http://dx.doi.org/10.1142/s0219887818501281.

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Making use of the modern techniques of non-holonomic geometry and constrained variational calculus, a revisitation of Ostrogradsky’s Hamiltonian formulation of the evolution equations determined by a Lagrangian of order [Formula: see text] in the derivatives of the configuration variables is presented.

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Lizón-Nordström, A., and Félix Yndurain. "Geometrical configuration of interstitial oxygen in silicon and in germanium." Solid State Communications 89, no. 9 (March 1994): 819–22. http://dx.doi.org/10.1016/0038-1098(94)90740-4.

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Schmah, Tanya, and Cristina Stoica. "On the n -body problem in R4." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2158 (September 30, 2019): 20190018. http://dx.doi.org/10.1098/rsta.2019.0018.

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Using geometric mechanics methods, we examine aspects of the dynamics of n mass points in R 4 with a general pairwise potential. We investigate the central force problem, set up the n -body problem and discuss certain properties of relative equilibria. We describe regular n -gons in R 4 , and when the masses are equal we determine the invariant manifold of motions with regular n -gon configurations. In the case n = 3, we reduce the dynamics to a 6 d.f. system and we show that for generic potentials and momenta, relative equilibria with equilateral configuration are unstable. This article is part of the theme issue ‘Topological and geometrical aspects of mass and vortex dynamics’.

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Bruot, Nicolas, and Pietro Cicuta. "Emergence of polar order and cooperativity in hydrodynamically coupled model cilia." Journal of The Royal Society Interface 10, no. 87 (October 6, 2013): 20130571. http://dx.doi.org/10.1098/rsif.2013.0571.

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As a model of ciliary beat, we use two-state oscillators that have a defined direction of oscillation and have strong synchronization properties. By allowing the direction of oscillation to vary according to the interaction with the fluid, with a timescale longer than the timescale of synchronization, we show in simulations that several oscillators can align in a direction set by the geometrical configuration of the system. In this system, the alignment depends on the state of synchronization of the system, and is therefore linked to the beat pattern of the model cilia. By testing various configurations from two to 64 oscillators, we deduce empirically that, when the synchronization state of neighbouring oscillators is in phase, the angles of the oscillators align in a configuration of high hydrodynamic coupling. In arrays of oscillators that break the planar symmetry, a global direction of alignment emerges reflecting this polarity. In symmetric configurations, where several directions are geometrically equivalent, the array still displays strong internal cooperative behaviour. It also appears that the shape of the array is more important than the lattice type and orientation in determining the preferred direction.

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Ito, Makoto, and Tsu-Wei Chou. "An Analytical and Experimental Study of Strength and Failure Behavior of Plain Weave Composites." Journal of Composite Materials 32, no. 1 (January 1998): 2–30. http://dx.doi.org/10.1177/002199839803200101.

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This paper analyzes the strengxth and failure behavior of plain weave composites. First, the geometrical characteristics of yarn shape, laminate stacking configuration, fiber volume fraction, and yarn packing fraction are investigated using three-dimensional geometrical models. Based on the geometrical characteristics, iso-strain approach is developed to predict elastic properties, stress distributions, and strengths under tensile loading. The laminate stacking configuration and fabric waviness ratio have significant influence on the composite failure behavior. Specimens of iso-phase, out-of-phase and random-phase laminate composites are prepared. The mathematical models developed are evaluated by microscopic observation and tensile tests.

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Hu, Yuan-Chao, Yan-Wei Li, Yong Yang, Peng-Fei Guan, Hai-Yang Bai, and Wei-Hua Wang. "Configuration correlation governs slow dynamics of supercooled metallic liquids." Proceedings of the National Academy of Sciences 115, no. 25 (June 4, 2018): 6375–80. http://dx.doi.org/10.1073/pnas.1802300115.

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The origin of dramatic slowing down of dynamics in metallic glass-forming liquids toward their glass transition temperatures is a fundamental but unresolved issue. Through extensive molecular dynamics simulations, here we show that, contrary to the previous beliefs, it is not local geometrical orderings extracted from instantaneous configurations but the intrinsic correlation between configurations that captures the structural origin governing slow dynamics. More significantly, it is demonstrated by scaling analyses that it is the correlation length extracted from configuration correlation rather than dynamic correlation lengths that is the key to determine the drastic slowdown of supercooled metallic liquids. The key role of the configuration correlation established here sheds important light on the structural origin of the mysterious glass transition and provides an essential piece of the puzzle for the development of a universal theoretical understanding of glass transition in glasses.

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Pandolfi, Anna, and Andrea Montanino. "On the recovery of the stress-free configuration of the human cornea." Modeling and Artificial Intelligence in Ophthalmology 2, no. 4 (June 16, 2020): 11–33. http://dx.doi.org/10.35119/maio.v2i4.106.

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Purpose: The geometries used to conduct numerical simulations of the biomechanics of the human cornea are reconstructed from images of the physiological configuration of the system, which is not in a stress-free state because of the interaction with the surrounding tissues. If the goal of the simulation is a realistic estimation of the mechanical engagement of the system, it is mandatory to obtain a stress-free configuration to which the external actions can be applied. Methods: Starting from a unique physiological image, the search of the stress-free configuration must be based on methods of inverse analysis. Inverse analysis assumes the knowledge of one or more geometrical configurations and, chosen a material model, obtains the optimal values of the material parameters that provide the numerical configurations closest to the physiological images. Given the multiplicity of available material models, the solution is not unique. Results: Three exemplary material models are used in this study to demonstrate that the obtained, non-unique, stress-free configuration is indeed strongly dependent on both material model and on material parameters. Conclusion: The likeliness of recovering the actual stress-free configuration of the human cornea can be improved by using and comparing two or more imaged configurations of the same cornea.

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Dedkov, George, and Arthur Kyasov. "Dynamically and thermally nonequilibrium fluctuation-electromagnetic interactions: Recent results and trends." Modern Physics Letters A 35, no. 03 (January 16, 2020): 2040013. http://dx.doi.org/10.1142/s0217732320400131.

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Our recent theoretical developments related to the nonrelativistic and relativistic fluctuation-electromagnetic interactions of bodies with different temperatures moving translationally and (or) rotationally relative to each other are briefly summarized. Three basic geometrical configurations and physical systems are discussed: “a small particle and a thick plate” (i); “a small particle in a radiative vacuum background” (ii) and “two thick plates in relative motion” (iii) — classical Casimir-Lifshitz configuration with allowance for relative motion and different temperatures of plates. For configuration 3, it is shown that the theory of friction and heat exchange by Levin-Polevoi-Rytov proves to be quite adequate contrary to the settled point of view of many authors.

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ELLICOTT, P., G. KUNSTATTER, and D. J. TOMS. "GEOMETRICAL DERIVATION OF THE FADDEEV-POPOV ANSATZ." Modern Physics Letters A 04, no. 24 (November 20, 1989): 2397–407. http://dx.doi.org/10.1142/s0217732389002689.

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A geometrical derivation of the Faddeev-Popov measure is presented. This derivation is valid in any gauge for a general class of gauge theories, including Yang-Mills theory, gravitation and non-linear sigma models, and can easily be generalized to include supersymmetric theories. We stress the role of a non-trivial, finite contribution to the effective action from the invariant measure on the orbit over each point in the physical configuration space.

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Zinka, S. R., Il-Bong Jeong, Jong-Hoon Chun, and Jeong-Phill Kim. "A Novel Geometrical Technique for Determining Optimal Array Antenna Lattice Configuration." IEEE Transactions on Antennas and Propagation 58, no. 2 (February 2010): 404–12. http://dx.doi.org/10.1109/tap.2009.2026920.

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Villarroel, J., O. Caballero-Calero, M. Carrascosa, A. García-Cabañes, and J. M. Cabrera. "Influence of the Geometrical Configuration on Optical Damage of LiNbO3Planar Waveguides." Ferroelectrics 390, no. 1 (October 28, 2009): 36–40. http://dx.doi.org/10.1080/00150190902993432.

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Goodall, Colin R., and Kanti V. Mardia. "A geometrical derivation of the shape density." Advances in Applied Probability 23, no. 03 (September 1991): 496–514. http://dx.doi.org/10.1017/s0001867800023703.

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The density for the shapes of random configurations of N independent Gaussian-distributed landmarks in the plane with unequal means was first derived by Mardia and Dryden (1989a). Kendall (1984), (1989) describes a hierarchy of spaces for landmarks, including Euclidean figure space containing the original configuration, preform space (with location removed), preshape space (with location and scale removed), and shape space. We derive the joint density of the landmark points in each of these intermediate spaces, culminating in confirmation of the Mardia–Dryden result in shape space. This three-step derivation is an appealing alternative to the single-step original derivation, and also provides strong geometrical motivation and insight into Kendall's hierarchy. Preform space and preshape space are respectively Euclidean space with dimension 2(N–1) and the sphere in that space, and thus the first two steps are reasonably familiar. The third step, from preshape space to shape space, is more interesting. The quotient by the rotation group partitions the preshape sphere into equivalence classes of preshapes with the same shape. We introduce a canonical system of preshape coordinates that include 2(N–2) polar coordinates for shape and one coordinate for rotation. Integration over the rotation coordinate gives the Mardia–Dryden result. However, the usual geometrical intuition fails because the set of preshapes keeping the rotation coordinate (however chosen) fixed is not an integrable manifold. We characterize the geometry of the quotient operation through the relationships between distances in preshape space and distances among the corresponding shapes.

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Goodall, Colin R., and Kanti V. Mardia. "A geometrical derivation of the shape density." Advances in Applied Probability 23, no. 3 (September 1991): 496–514. http://dx.doi.org/10.2307/1427619.

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The density for the shapes of random configurations of N independent Gaussian-distributed landmarks in the plane with unequal means was first derived by Mardia and Dryden (1989a). Kendall (1984), (1989) describes a hierarchy of spaces for landmarks, including Euclidean figure space containing the original configuration, preform space (with location removed), preshape space (with location and scale removed), and shape space. We derive the joint density of the landmark points in each of these intermediate spaces, culminating in confirmation of the Mardia–Dryden result in shape space. This three-step derivation is an appealing alternative to the single-step original derivation, and also provides strong geometrical motivation and insight into Kendall's hierarchy. Preform space and preshape space are respectively Euclidean space with dimension 2(N–1) and the sphere in that space, and thus the first two steps are reasonably familiar. The third step, from preshape space to shape space, is more interesting. The quotient by the rotation group partitions the preshape sphere into equivalence classes of preshapes with the same shape. We introduce a canonical system of preshape coordinates that include 2(N–2) polar coordinates for shape and one coordinate for rotation. Integration over the rotation coordinate gives the Mardia–Dryden result. However, the usual geometrical intuition fails because the set of preshapes keeping the rotation coordinate (however chosen) fixed is not an integrable manifold. We characterize the geometry of the quotient operation through the relationships between distances in preshape space and distances among the corresponding shapes.

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Rodrigues, José A. "Isogeometric Analysis for Fluid Shear Stress in Cancer Cells." Mathematical and Computational Applications 25, no. 2 (April 3, 2020): 19. http://dx.doi.org/10.3390/mca25020019.

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The microenvironment of the tumor is a key factor regulating tumor cell invasion and metastasis. The effects of physical factors in tumorigenesis is unclear. Shear stress, induced by liquid flow, plays a key role in proliferation, apoptosis, invasion, and metastasis of tumor cells. The mathematical models have the potential to elucidate the metastatic behavior of the cells’ membrane exposed to these microenvironment forces. Due to the shape configuration of the cancer cells, Non-uniform Rational B-splines (NURBS) lines are very adequate to define its geometric model. The Isogeometric Analysis allows a simplified transition of exact CAD models into the analysis avoiding the geometrical discontinuities of the traditional Galerkin traditional techniques. In this work, we use an isogeometric analysis to model the fluid-generated forces that tumor cells are exposed to in the vascular and tumor microenvironments, in the metastatic process. Using information provided by experimental tests in vitro, we present a suite of numerical experiments which indicate, for standard configurations, the metastatic behavior of cells exposed to such forces. The focus of this paper is strictly on geometrical sensitivities to the shear stress’ exhibition for the cell membrane, this being its innovation.

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Xiu, Shi Chao, Zhi Jie Geng, and Guang Qi Cai. "Study on Edge Contact Area and Surface Integrity of Workpiece in Point Grinding Process." Key Engineering Materials 407-408 (February 2009): 577–81. http://dx.doi.org/10.4028/www.scientific.net/kem.407-408.577.

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During cylindrical grinding process, the geometric configuration and size of the edge contact area between the grinding wheel and workpiece have the heavy effects on the workpiece surface integrity. In consideration of the differences between the point grinding and the conventional high speed cylindrical grinding, the geometric and mathematic models of the edge contact area in point grinding were established. Based on the models, the numerical simulation for the edge contact area was performed. By means of the point grinding experiment, the effect mechanism of the edge contact area on the ground surface integrity was investigated. These will offer the applied theoretic foundations for optimizing the point grinding angles, depth of cut, wheel and workpiece speed, geometrical configuration and size of CBN wheel and some other grinding parameters in point grinding process.

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Wu, Li Jun, Lin Zhang, and Yang Qi. "Structures and Electronic Properties of a Si₅₅ Cluster on DFTB Calculations." Materials Science Forum 815 (March 2015): 49–53. http://dx.doi.org/10.4028/www.scientific.net/msf.815.49.

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The lowest-energy geometrical structures of a cluster containing 55 atoms were searched by using the Density Functional Tight Binding (DFTB) combined with unbiased global optimization genetic algorithms (GAs) method. Two lowest-energy structures were obtained for the Si55 cluster with the appearance of “Y shape” and “like-spherical shape” configurations. The configuration dependence average energy, highest occupied and lowest unoccupied molecular (HOMO-LUMO) gap, electron transfer and molecular dipole moment were also discussed in details for this cluster.

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Rambousky, R., J. Nitsch, and S. Tkachenko. "Application of transmission-line super theory to classical transmission lines with risers." Advances in Radio Science 13 (November 3, 2015): 161–68. http://dx.doi.org/10.5194/ars-13-161-2015.

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Abstract. By applying the Transmission-Line Super Theory (TLST) to a practical transmission-line configuration (two risers and a horizontal part of the line parallel to the ground plane) it is elaborated under which physical and geometrical conditions the horizontal part of the transmission-line can be represented by a classical telegrapher equation with a sufficiently accurate description of the physical properties of the line. The risers together with the part of the horizontal line close to them are treated as separate lines using the TLST. Novel frequency and local dependent reflection coefficients are introduced to take into account the action of the bends and their radiation. They can be derived from the matrizant elements of the TLST solution. It is shown that the solution of the resulting network and the TLST solution of the entire line agree for certain line configurations. The physical and geometrical parameters for these corresponding configurations are determined in this paper.

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Knorr, Lukas, Robert Setter, Dominik Rietzel, Katrin Wudy, and Tim Osswald. "Comparative Analysis of the Impact of Additively Manufactured Polymer Tools on the Fiber Configuration of Injection Molded Long-Fiber-Reinforced Thermoplastics." Journal of Composites Science 4, no. 3 (September 15, 2020): 136. http://dx.doi.org/10.3390/jcs4030136.

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Additive tooling (AT) utilizes the advantages of rapid tooling development while minimizing geometrical limitations of conventional tool manufacturing such as complex design of cooling channels. This investigation presents a comparative experimental analysis of long-fiber-reinforced thermoplastic parts (LFTs), which are produced through additively manufactured injection molding polymer tools. After giving a review on the state of the art of AT and LFTs, additive manufacturing (AM) plastic tools are compared to conventionally manufactured steel and aluminum tools toward their qualification for spare part and small series production as well as functional validation. The assessment of the polymer tools focuses on three quality criteria concerning the LFT parts: geometrical accuracy, mechanical properties, and fiber configuration. The analysis of the fiber configuration includes fiber length, fiber concentration, and fiber orientation. The results show that polymer tools are fully capable of manufacturing LFTs with a cycle number within hundreds before showing critical signs of deterioration or tool failure. The produced LFTs moldings provide sufficient quality in geometrical accuracy, mechanical properties, and fiber configuration. Further, specific anomalies of the fiber configuration can be detected for all tool types, which include the occurrence of characteristic zones dependent on the nominal fiber content and melt flow distance. Conclusions toward the improvement of additively manufactured polymer tool life cycles are drawn based on the detected deteriorations and failure modes.

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Yan, J. F., W. J. Meng, Z. Chen, H. Guo, and X. G. Yan. "Numerical Determination of Critical Configuration for Mechanical Properties of Metallic Glasses with Notches." Science of Advanced Materials 13, no. 2 (February 1, 2021): 235–44. http://dx.doi.org/10.1166/sam.2021.3866.

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A numerical study based on a revised free-volume theory was carried out to determine the critical configuration for mechanical properties in metallic glass with notches. Firstly, parameters being used in constitutive laws were developed and validated to quantitatively describe the asymmetry of tension and compression. Then, systematical simulations under compressive loadings were performed on samples where different horizontal width and vertical distance of two adjacent notches were designed. Engineering stress-strain curves, global strength and uniform elongation were plotted against individual geometrical configuration. Analyses were carried out to reveal the shear banding process of different samples by means of free-volume distribution obtained by simulations. Conclusive illustration recommended a geometrical configuration by which notched samples could display a remarkable plasticity and high strength. It is helpful to material fabrication for metallic glass based porous materials.

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32

Obata, Tsuneshi, and Hiroaki Ishii. "A METHOD TO EVALUATE GEOMETRICAL CONFIGURATION OF CANDIDATES FROM RANKED PREFERENCE DATA." Journal of the Japanese Society of Computational Statistics 19, no. 1 (2006): 27–43. http://dx.doi.org/10.5183/jjscs1988.19.27.

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Kim, Do-Hyun, Min-Seok Kim, and Hong-Dae Kim. "Geometrical and electronic structures of graphene under different vacancy density and configuration." Applied Surface Science 359 (December 2015): 55–60. http://dx.doi.org/10.1016/j.apsusc.2015.10.055.

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Atherton, Harry, Yuying Xia, and John Kamalu. "The mechanical properties and geometrical configuration efficiency of multiple resistance spot welds." Advances in Materials and Processing Technologies 3, no. 3 (June 12, 2017): 449–62. http://dx.doi.org/10.1080/2374068x.2017.1338880.

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Kajikawa, K., M. Iwakuma, K. Funaki, M. Wada, and A. Takenaka. "Influences of geometrical configuration on AC loss measurement with pickup-coil method." IEEE Transactions on Appiled Superconductivity 9, no. 2 (June 1999): 746–49. http://dx.doi.org/10.1109/77.783402.

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Bo, Zheng, Jian Hua Yan, Xiao Dong Li, Yong Chi, Bruno Chéron, and Ke Fa Cen. "The Dependence of Gliding Arc Gas Discharge Characteristics on Reactor Geometrical Configuration." Plasma Chemistry and Plasma Processing 27, no. 6 (September 1, 2007): 691–700. http://dx.doi.org/10.1007/s11090-007-9102-2.

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Deli, Jo´zsef, Pe´ter Molna´r, Gyula To´th, Jo´zsef Szabolcs, and Lajos Radics. "Determination of the geometrical configuration of naturally occurring mono-cis-lutein epoxides." Phytochemistry 27, no. 2 (January 1988): 547–49. http://dx.doi.org/10.1016/0031-9422(88)83139-x.

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38

Hatanaka, S., T. Tuziuti, T. Kozuka, and H. Mitome. "Dependence of sonoluminescence intensity on the geometrical configuration of a reactor cell." IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control 48, no. 1 (January 2001): 28–36. http://dx.doi.org/10.1109/58.895902.

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Cipitì, F., L. Pino, A. Vita, M. Laganà, and V. Recupero. "Model-based analysis of reactor geometrical configuration on CO preferential oxidation performance." International Journal of Hydrogen Energy 34, no. 10 (May 2009): 4463–74. http://dx.doi.org/10.1016/j.ijhydene.2008.07.081.

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40

Wong, C. K., and Yi Liu. "Lane-based optimization for signalized network configuration designs." MATEC Web of Conferences 272 (2019): 01048. http://dx.doi.org/10.1051/matecconf/201927201048.

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Lane-based traffic signal design has been developed for designing signal-controlled intersections. Conventional designs take on fixed configurations as exogenous inputs to design traffic signal settings. The proposed study will be an extension to merge geometrical junction arrangement and signal controls together for network configuration designs. Design methodology would be directly extended from existing lane-based design method. New Path flows variables and new flow conservation constraints are required to ensure the users’ input OD flows could be assigned onto network paths through different signal-controlled intersections. This problem is new that involves binary variables and related linear constraints which is formulated as a BMILP. Standard technique could solve the optimum solution. A four-intersection network with two approach lane settings is optimized for demonstration purposes.

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Choi, Chun Kit K., Xiaolu Zhuo, Yee Ting Elaine Chiu, Hongrong Yang, Jianfang Wang, and Chung Hang Jonathan Choi. "Polydopamine-based concentric nanoshells with programmable architectures and plasmonic properties." Nanoscale 9, no. 43 (2017): 16968–80. http://dx.doi.org/10.1039/c7nr05451c.

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MATONE, MARCO. "THE HIGGS MODEL FOR ANYONS AND LIOUVILLE ACTION: CHAOTIC SPECTRUM, ENERGY GAP AND EXCLUSION PRINCIPLE." Modern Physics Letters A 09, no. 18 (June 14, 1994): 1673–80. http://dx.doi.org/10.1142/s0217732394001519.

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The requirements of geodesic completeness and self-adjointness imply that the Hamiltonian for anyons is the Laplacian with respect to the Weil-Petersson metric. This metric is complete on the Deligne-Mumford compactification of moduli (configuration) space. The structure of this compactification fixes the possible anyon configurations. This allows us to identify anyons with singularities (elliptic points with ramification q−1) in the Poincare metric implying that anyon spectrum is chaotic for n≥3. Furthermore, the bound on the holomorphic sectional curvature of moduli spaces implies a gap in the energy spectrum. For q=0 (punctures) anyons are infinitely separated in the Poincare metric (hard core). This indicates that the exclusion principle has a geometrical interpretation. Finally we give the differential equation satisfied by the generating function for volumes of the configuration space of anyons.

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Yadmellat, Peyman, and Rajni V. Patel. "Frequency response analysis of magneto-rheological clutch designs." Journal of Intelligent Material Systems and Structures 29, no. 5 (August 4, 2017): 905–23. http://dx.doi.org/10.1177/1045389x17721058.

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This article presents the frequency response analysis performed on two different geometrical configurations of magneto-rheological clutches including disk-based and drum-based configurations. For each configuration, two sub-configurations with inner coil and outer coil designs are studied. The configurations are thoroughly studied with respect to the effect of design parameters on the bandwidth of magneto-rheological clutches using finite element analysis and by considering the effect of eddy currents and the skin effect in the magnetic circuit. The N-way analysis of variance is used to study the effect of the main parameters as well as interaction between the parameters on the bandwidth. Furthermore, trade-offs between the effect of the main parameters and the torque capacity are discussed.

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Cheng, Chin-Hsiang, and Mei-Hsia Chang. "Shape Identification by Inverse Heat Transfer Method." Journal of Heat Transfer 125, no. 2 (March 21, 2003): 224–31. http://dx.doi.org/10.1115/1.1560152.

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The aim of this study is to investigate the performance of the inverse heat transfer method in application to the shape identification problem. The approach is constructed by combining the curvilinear grid generation scheme, the direct problem solver, the conjugate gradient optimization method, and the redistribution method. A number of practical cases are considered, in which shape identification for an inner void within a solid body based on the data of the outer surface temperature of the solid body is performed. These cases are divided into five kinds of geometrical configurations. Results show that the profile of the inner void can be identified by using the inverse heat transfer approach, and the accuracy of the shape identification is dependent on the uncertainty of the outer surface temperature data, the Biot number, size of the inner void, and the geometrical configuration as well.

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Zaiter, Mohammad Ali, Régis Lherbier, Ghaleb Faour, Oussama Bazzi, and Jean-Charles Noyer. "Extrinsic LiDAR/Ground Calibration Method Using 3D Geometrical Plane-Based Estimation." Sensors 20, no. 10 (May 16, 2020): 2841. http://dx.doi.org/10.3390/s20102841.

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This paper details a new extrinsic calibration method for scanning laser rangefinder that is precisely focused on the geometrical ground plane-based estimation. This method is also efficient in the challenging experimental configuration of a high angle of inclination of the LiDAR. In this configuration, the calibration of the LiDAR sensor is a key problem that can be be found in various domains and in particular to guarantee the efficiency of ground surface object detection. The proposed extrinsic calibration method can be summarized by the following procedure steps: fitting ground plane, extrinsic parameters estimation (3D orientation angles and altitude), and extrinsic parameters optimization. Finally, the results are presented in terms of precision and robustness against the variation of LiDAR’s orientation and range accuracy, respectively, showing the stability and the accuracy of the proposed extrinsic calibration method, which was validated through numerical simulation and real data to prove the method performance.

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Anselmo, G., and A. Fandella. "Detubularization and/or reconfiguration." Urologia Journal 63, no. 4 (August 1996): 487–90. http://dx.doi.org/10.1177/039156039606300414.

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Technical variants of reservoir construction can develop from in-depth knowledge of the important physiopathological implications involved in the choice of whole intestinal segments and especially the aperture and reconfiguration of the segment. The physical geometrical and physiological principles applied to clinical practice are therefore described, represented by the configuration or geometrical capacity, the accommodation, the visco-elasticity or compliance and the contractility.

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Dobias, Peter, and John C. Samson. "Nonlinear instabilities in magnetized plasmas: a geometrical treatment." Canadian Journal of Physics 82, no. 8 (August 1, 2004): 593–608. http://dx.doi.org/10.1139/p04-033.

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The objectives of this paper are four-fold. The first, and main concern, is the development of an alternative approach to the description of plasma physics using methods of differential geometry. These methods have long been used in many other areas of physics, such as general relativity, or quantum field theory, but do not seem to have seen extensive application in plasma physics, and in particular in magnetohydrodynamics (MHD). The second objective is to employ this formalism for perturbation calculations, particularly to nonlinear processes in MHD. The use of differential geometry for variational calculations in ideal MHD allows a self-consistent, and compact calculation of the Lagrangian, and yields results valid for arbitrary topologies of the magnetic field. The third objective is to outline the use of this formalism in analyzing several plasma processes that occur in systems with complex magnetic-field topologies. We specifically focus on the nonlinear stability of plasmas in the magnetotail-like configuration of the magnetic field, such as found in the Earth's magnetosphere. Finally, we utilize previous results to present a self-consistent method for the investigation of the nonlinear stability of magnetized plasmas and for the investigation of the transition between linear and nonlinearbehavior for systems close to equilibrium. This method is based on the analysis of potential energy density, using results for plasma displacement from a linear model to calculate the second- andthird-order energies. We demonstrate this method on an example of a force-free field with magnetic-field lines stretched from dipolar configuration. In this example, we can clearly identify the transition between linear and nonlinear instability. PACS Nos.: 52.30.g, 52.35.g

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ANAZAWA, MASAHIRO, and ATUSHI ISHIKAWA. "GEOMETRICAL CONSTRUCTION OF HETEROGENEOUS LOOP AMPLITUDES IN 2D GRAVITY." International Journal of Modern Physics A 17, no. 28 (November 10, 2002): 4069–80. http://dx.doi.org/10.1142/s0217751x02011448.

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We study a disk amplitude which has a complicated heterogeneous matter configuration on the boundary in a system of the (3,4) conformal matter coupled to two-dimensional gravity. It is analyzed using the two-matrix chain model in the large N limit. We show that the disk amplitude calculated by Schwinger–Dyson equations can be completely reproduced through purely geometrical consideration. From this result, we speculate that all heterogeneous loop amplitudes can be derived from the geometrical consideration and the consistency among relevant amplitudes.

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Pianko-Oprych, Paulina, and Zdzisław Jaworski. "3D CFD fluid flow and thermal analyses of a new design of plate heat exchanger." Polish Journal of Chemical Technology 19, no. 1 (March 28, 2017): 17–26. http://dx.doi.org/10.1515/pjct-2017-0003.

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Abstract The paper presents a Computational Fluid Dynamics (CFD) numerical study for a new design of a plate heat exchanger with two different flow patterns. The impact of geometric characteristics of the two studied geometries of exchanger plates on the intensification process of heat transfer was considered. The velocity, temperature and pressure distributions along the heat exchanger were examined. The CFD results were validated against experimental data and a good agreement was achieved. The results revealed that geometrical arrangement of the plates strongly influence the fluid flow. An increase in the Reynolds number led to lowering the friction factor value and increasing the pressure drop. The configuration II of the plate heat exchanger resulted in lower outlet hot fluid temperature in comparison with the configuration I, which means improvement of heat transfer.

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Madhusudhan, K., M. V. Narasimhan, and R. V. Ravikrishna. "A new cyclone separator-based pre-filter design for internal combustion engine applications. Part 2: Parametric study and optimization." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 220, no. 12 (December 1, 2006): 1755–64. http://dx.doi.org/10.1243/0954406jmes171.

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In a previous paper a new design was presented of a cyclone separator based pre-filter along with validation of a numerical model with experimental data. The validated model is used to evaluate certain designs with varying inlet air entry configurations. Furthermore, several cases as part of a detailed parametric study on the new pre-filter design are simulated in terms of geometrical parameters to optimize the performance with respect to overall pressure drop and dust collection efficiency. The results of the parametric study are used to derive a final optimized pre-filter configuration. In addition, based on the results of some of the simulations, a new concept of air filtration which could potentially replace the conventional air filter plus pre-filter configuration is introduced and assessed numerically. This design utilizes the high swirl velocities of air to separate particles as small as 4-5 μm with almost 100 per cent efficiency. More importantly, it offers much lower pressure drop than the total pre-filter plus main filter configuration.

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Journal articles on the topic 'Geometrical configuration'

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