Search results for " surface"
showing 10 items of 2838 documents
A multi-objective Pareto design approach for simultaneous control of thinning and springback in complex stamping operations.
2009
Abstract In sheet metal forming operations design, optimization problems have to be solved in order to reach optimal process conditions. In these problems, there are some crucial issues to be taken into account: - most of the problems are multi objective problems, generally characterized by conflicting objectives: the definition of proper parameters aimed to prevent both springback and fracture is a typical example of an optimization problem in sheet metal forming characterized by conflicting goals; - in an industrial environment a great interest would be focused on the availability of a cluster of possible optimal solutions instead of a single “almost optimal” solution. Taking into account…
The Essential Oil of
2019
Many chemicals used nowadays for the preservation of cultural heritage pose a risk to both human health and the environment. Thus, it is desirable to find new and eco-friendly biocides that can replace the synthetic ones. In this regard, plant essential oils represent effective alternatives to synthetic substances for the preservation of historical monuments. Thymbra capitata (syn. Thymus capitatus) is a medicinal and aromatic plant growing in the Mediterranean area and endowed with important pharmacological properties related to its essential oil. Among them, the antimicrobial ones make the T. capitata essential oil an ideal candidate for industrial applications; for instance, as biocide f…
Reverse Catmull-Clark Subdivision
2006
Reverse subdivision consists in constructing a coarse mesh of a model from a finer mesh of this same model. In this paper, we give formulas for reverse Catmull-Clark subdivision. These formulas allow the constructing of a coarse mesh for almost all meshes. The condition for being able to apply these formulas is that the mesh to be reversed must be generated by the subdivision of a coarse mesh. Except for this condition, the mesh can be arbitrary. Vertices can be regular or extraordinary and the mesh itself can be arbitrary (triangular, quadrilateral…).
Ositusmetodit reaaliaikaisessa renderöinnissä
2017
Tietokonegrafiikka ja siihen liittyvät menetelmät ovat nopeasti kehittyvä tutkimuksen ala. Tämän tutkimuksen tavoitteena on pohtia eri ositusmenetelmien toimintaa reaaliaikaisessa käytössä sekä vertailla näitä menetelmiä. Nykyaikaiselle käytölle tehokkaimmaksi osoittautui kolmesta tutkitusta menetelmästä tuorein (Brainerd ym. 2016). Tulevassa tutkimuksessa laitteistointegraatioon keskittyminen voisi tuoda ositusmenetelmät nopeammin kuluttajien saataville. Computergraphicsanditsmethodsarearapidlydevelopingfieldinresearch.The purpose of this study is to discuss and compare the functionality of several subdivision methods in real-time use. The latest of the three studied methods turned out to be…
The Radó–Kneser–Choquet theorem for $p$-harmonic mappings between Riemannian surfaces
2020
In the planar setting the Rad\'o-Kneser-Choquet theorem states that a harmonic map from the unit disk onto a Jordan domain bounded by a convex curve is a diffeomorphism provided that the boundary mapping is a homeomorphism. We prove the injectivity criterion of Rad\'o-Kneser-Choquet for $p$-harmonic mappings between Riemannian surfaces. In our proof of the injecticity criterion we approximate the $p$-harmonic map with auxiliary mappings that solve uniformly elliptic systems. We prove that each auxiliary mapping has a positive Jacobian by a homotopy argument. We keep the maps injective all the way through the homotopy with the help of the minimum principle for a certain subharmonic expressio…
Joint Subcarrier and Phase Shifts Optimization for RIS-aided Localization-Communication System
2022
Joint localization and communication systems have drawn significant attention due to their high resource utilization. In this paper, we consider a reconfigurable intelligent surface (RIS)-aided simultaneously localization and communication system. We first determine the sum squared position error bound (SPEB) as the localization accuracy metric for the presented localization-communication system. Then, a joint RIS discrete phase shifts design and subcarrier assignment problem is formulated to minimize the SPEB while guaranteeing each user’s achievable data rate requirement. For the presented non-convex mixed-integer problem, we propose an iterative algorithm to obtain a suboptimal solution …
Competition of electron-phonon mediated superconductivity and Stoner magnetism on a flat band
2018
The effective attractive interaction between electrons, mediated by electron-phonon coupling, is a well-established mechanism of conventional superconductivity. In metals exhibiting a Fermi surface, the critical temperature of superconductivity is exponentially smaller than the characteristic phonon energy. Therefore, such superconductors are found only at temperatures below a few kelvin. Systems with flat energy bands have been suggested to cure the problem and provide a route to room-temperature superconductivity, but previous studies are limited to only BCS models with an effective attractive interaction. Here we generalize Eliashberg's theory of strong-coupling superconductivity to syst…
The Role of Surface Acting in the Relationship between Job Stressors, General Health and Need for Recovery Based on the Frequency of Interactions at …
2022
The aim of the study was to verify whether the frequency of face-to-face interactions with the public at work can reveal differences in how people react to emotional regulation demands. In particular, we investigated the mediating role of surface acting (a strategy of dealing with emotional dissonance) in the relationship between two typical job stressors (workload and mental load) and two outcomes closely related to work-related well-being: employees’ general health and the need for recovery. Prior studies investigating the detrimental effects of emotional dissonance mostly focused on service workers. However, in light of a survey conducted by the European Agency for Safety and Health at W…
Saddle index properties, singular topology, and its relation to thermodynamic singularities for aϕ4mean-field model
2004
We investigate the potential energy surface of a ${\ensuremath{\phi}}^{4}$ model with infinite range interactions. All stationary points can be uniquely characterized by three real numbers ${\ensuremath{\alpha}}_{+},{\ensuremath{\alpha}}_{0},{\ensuremath{\alpha}}_{\ensuremath{-}}$ with ${\ensuremath{\alpha}}_{+}+{\ensuremath{\alpha}}_{0}+{\ensuremath{\alpha}}_{\ensuremath{-}}=1$, provided that the interaction strength $\ensuremath{\mu}$ is smaller than a critical value. The saddle index ${n}_{s}$ is equal to ${\ensuremath{\alpha}}_{0}$ and its distribution function has a maximum at ${n}_{s}^{\mathrm{max}}=1∕3$. The density $p(e)$ of stationary points with energy per particle $e$, as well as…
Methods for estimating forest stem volumes by tree species using digital surface model and CIR images taken from light UAS
2012
In this paper we consider methods for estimating forest tree stem volumes by species using images taken from light unmanned aircraft systems (UAS). Instead of using LiDAR and additional multiband imagery a color infrared camera mounted to a light UAS is used to acquire both imagery and the DSM of target area. The goal of this study is to accurately estimate tree stem volumes in three classes. The status of the ongoing work is described and an initial method for delineating and classifying treetops is presented.