3D garment positioning using Hermite radial basis functions

Virtual Reality - Fitting an elegant 3D garment model onto a target 3D human model is crucial for garment design industry and virtual try-on systems. The alignment of the garment onto virtual...     

Nonlocal PDEs on Graphs: From Tug-of-War Games to Unified Interpolation on Images and Point Clouds

In this paper, we introduce a new general class of partial difference operators on graphs, which interpolate between the nonlocal \(\infty \)-Laplacian, the Laplacian, and a family of discrete gradient operators. In this context, we investigate an associated Dirichlet problem for this general class of operators and prove the existence and uniqueness of respective solutions. We show that a certain partial difference equation based on this class of operators recovers many variants of a stochastic game known as ‘Tug-of-War’ and extends them to a nonlocal setting. Furthermore, we discuss a connection with certain nonlocal partial differential equations. Finally, we propose to use this class of operators as general framework to solve many interpolation problems in a unified manner as arising, e.g., in image and point cloud processing.     

In-situ thermoset polyurethane coating of glass beads dispersed in polystyrene by reactive extrusion

The condensation reaction between hydroxyl terminated polybutadiene and an uritonimine modified 4, 4 diphenylmethane diisocyanate (liquid MDI) was carried out by reactive extrusion in the presence of propyl trietoxy amino silane treated glass-beads and polystyrene. Reactants were selected having a surface tension favoring the glass bead coating using the spreading coefficient concept. FTIR, SEC (size exclusion chromatography) and rheological analysis of the resultant material showed that condensation reaction had occurred leading to crosslinked Polyurethane located principally around the glass beads.     

Multimedia Multicast in Mobile Computing: Handoff Management

With rapid technological advances being made in the area of wireless communications it is expected that, in the near future, mobile users will be able to access a wide variety of services such as multicast distribution of multimedia streams. These services are characterized by the integrated processing of different media types, such as audio and video. Different multimedia streams must be played out in a synchronized way. However, due to the asynchronous nature of the communication (packets or radio), some problems can disrupt the synchronization such as delay jitter. In this paper, we present a synchronization protocol for multicast of multimedia streams. It allows a mobile host to playback continuously a multimedia stream. When a mobile host moves from cell to cell, the scheme allows continuous playback. The mechanism used is based on the pre-buffering of media units. We present a computation of the handoff time and a mechanism for the restoration of the initial buffer size. Simulation results show that, when resources are already reserved, the handoff time is bounded and the buffer takes again its initial size.     

Effect of the Fiber Size on the Physicochemical and Mechanical Properties of Composites of Epoxy and Date Palm Tree Fibers

Lignocellulosic fibers from date palm trees were employed to reinforce an epoxy matrix. Two fiber sizes were used, with the length and diameter in the range of 20–30 and 1.5–3 mm, respectively, for the so‐called long fibers, and in the range of 5–15 and 0.25–0.75 mm, respectively, for the so‐called short fibers. The morphologies of the resulting composites, as well as their thermal, mechanical, and water sorption properties were evaluated. Strong interactions between both components and etherification reactions may occur between the hydroxyl groups of the fibers and the epoxy groups of the epoxy‐amine reactive mixture. These effects are emphasized when decreasing the size of the fibers.

     

Human platelet antigens polymorphisms and susceptibility of thrombosis in hemodialysis patients

To investigate the association between the polymorphisms of human platelet antigen (HPA)-1,2,3,4,5 and susceptibility to develop thrombosis accident in arteriovenous fistula (AVF), genomic DNA of 112 hemodialysis (HD) patients and 100 healthy blood donors were genotyped by PCR-SSP. The patients were classified into 2 groups: G1 included 54 HD patients presented at least one thrombotic episode on the level of the AVF, and G2 included 58 HD patients without any episode of thrombosis. The allelic frequencies of HPA-1, 2, 3, and 5 among patients and controls did not reveal significant differences. However, the HPA-4b allele was significantly more frequent in G1 than in controls or in G2 patients (23.1% vs. 11.5% and 0.9%, respectively), p<0.01 and p<0.001. The genotype distribution of HPA-4 polymorphism reveals that the HPA-4a4b genotype was more frequent in G1 patients (23/54: 42.6%) than in all HD patients (25/112: 22.3%) or in G2 patients (1/58: 1.72%) (p<0.001, odds ratio: 45.6). Among 24 HD patients with HPA-4a4b genotype, 23 (96%) developed at least 1 or more thrombotic episode on the level of their AVF. However, 30 patients (34.5%) among 87 HD patients with HPA-4a4a genotype presented thrombotic episode (p<0.001). These results reveal a significant association between HPA-4a4b and thrombosis, and it is likely that HPA polymorphisms could be useful markers for potential risk of thrombosis in hemodialysis.     

Generalized differential quadrature analysis of electro-magneto-hydrodynamic dissipative flows over a heated Riga plate in the presence of a space-dependent heat source: The case for strong suction effect

The importance of including an electromagnetic actuator as a moving boundary on the dissipative flows of weakly conducting fluids had led to many published facts. But, nothing is known on the generalized differential quadrature analysis of magnetohydrodynamics over a Riga plate with emphasis on the case of viscous dissipation and space-dependent heat source. After deriving the simplified boundary layer equation that models the transport phenomenon, appropriate variables were used to non-dimensionalize and parameterize the partial differential equations. Thereafter, the resulting set of ordinary differential equations was solved numerically by applying a powerful differential quadrature algorithm. Based on the outcome of the simulation, it can be concluded that the viscous frictional effect can be minimized at the Riga plate either by weakening the suction process or by heightening the magnetic parameter. Moreover, the Lorentz forces have a hastening effect on the fluid motion, in the case when those magnetic causes are directed in the same sense of the developed flow.     

Machine learning methods to forecast temperature in buildings

Efficient management of energy in buildings saves a very important amount of resources (both economic and technological). As a consequence, there is a very active research in this field. One of the keys of energy management is the prediction of the variables that directly affect building energy consumption and personal comfort. Among these variables, one can highlight the temperature in each room of a building. In this work we apply different machine learning techniques along with other classical ones for predicting the temperatures in different rooms. The obtained results demonstrate the validity of these techniques for predicting temperatures and, therefore, for the establishment of optimal policies of energy consumption.     

Large amplitude free vibration of a shear deformable laminated composite parabolic plate with parabolically orthotropic plies

The large amplitude free vibration of a laminated composite parabolic plate with parabolically orthotropic plies is investigated for the first time. The effects of out-of-plane shear deformations, rotary inertia, and geometrical nonlinearity are taken into account. The geometry of the plate is described, and the analysis performed in the parabolic coordinate system. The problem is solved numerically using a new parabolic hierarchical finite element. The nonlinear equations of free motion are mapped from the time domain into the frequency domain using the harmonic balance method. The resultant nonlinear equations are solved iteratively using the linearized updated mode method. Results for the fundamental linear and nonlinear frequencies are obtained for symmetric and antisymmetric laminates with clamped and simply supported edges. Comparisons are made with the finite element method for clamped and free isotropic parabolic plates and show excellent agreement. The aspect ratio, thickness ratio, moduli ratio, number of plies, layup sequence, and boundary conditions are shown to affect the hardening behavior.