HEGM: A hierarchical elastic graph matching for hand gesture recognition

A hierarchical scheme for elastic graph matching applied to hand gesture recognition is proposed. The proposed algorithm exploits the relative discriminatory capabilities of visual features scattered on the images, assigning the corresponding weights to each feature. A boosting algorithm is used to determine the structure of the hierarchy of a given graph. The graph is expressed by annotating the nodes of interest over the target object to form a bunch graph. Three annotation techniques, manual, semi-automatic, and automatic annotation are used to determine the position of the nodes. The scheme and the annotation approaches are applied to explore the hand gesture recognition performance. A number of filter banks are applied to hand gestures images to investigate the effect of using different feature representation approaches. Experimental results show that the hierarchical elastic graph matching (HEGM) approach classified the hand posture with a gesture recognition accuracy of 99.85% when visual features were extracted by utilizing the Histogram of Oriented Gradient (HOG) representation. The results also provide the performance measures from the aspect of recognition accuracy to matching benefits, node positions correlation and consistency on three annotation approaches, showing that the semi-automatic annotation method is more efficient and accurate than the other two methods.     

Assessing task understanding in remote ultrasound diagnosis via gesture analysis

Pattern Analysis and Applications - This work presents a gesture-based approach to estimate task understanding and performance during remote ultrasound tasks. Our approach is comprised of...     

An electrospray ionization source for integration with microfluidics

We have demonstrated a new electrospray ionization (ESI) device incorporating a tip made from a shaped thin film, bonded to a microfluidic channel, and interfaced to a time-of-flight mass spectrometer (TOFMS). A triangular-shaped thin polymer tip was formed by lithography and etching. A microfluidic channel, 20 microm wide and 10 microm deep, was embossed in a cyclo olefin substrate using a silicon master. The triangular tip was aligned with the channel and bonded between the channel plate and a flat plate to create a microfluidic channel with a wicking tip protruding from the end. This structure aided the formation of a stable Taylor cone at the apex of the tip, forming an electrospray ionization source. This source was tested by spraying several solutions for mass spectrometric analysis. Because the components are all made by lithographic approaches with high geometrical fidelity, an integrated array system with multiple channels can be formed with the same method and ease as a single channel. We tested a multichannel system in a multiplexed manner and showed reliable operation with no significant cross contamination between closely spaced channels.     

Molecular design of supported niobium oxide catalysts

The current investigation demonstrates that it is possible to molecularly design supported niobium oxide catalysts with the assistance of molecular characterization methods such as Raman spectroscopy. The formation and location of the surface niobium oxide species are controlled by the surface hydroxyl chemistry, and the surface niobium oxide species are located in the outermost layer of the catalysts as an overlayer. The catalyst composition is a critical parameter since it affects the presence of different niobium oxide species (several different surface species and crystalline phases), and the reactivity also varies somewhat with surface niobium oxide coverage. The preparation method is not a critical parameter since it does not appear to influence the structure or reactivity of the surface niobium oxide species. However, for silica supported niobium oxide catalysts the preparation method does affect the amount of niobium oxide that can be dispersed as a two-dimensional overlayer. Calcination temperature is an important parameter that controls the activation and deactivation of the supported niobium oxide catalysts, but calcination temperature is not critical if moderate temperatures, 400–500°C, are used. The specific oxide support is a critical parameter since it dramatically affects the reactivity of the surface niobium oxide species and determines if the surface niobium oxide site is active for redox or acid catalysis. Thus, the critical parameters that affect the catalytic properties of the supported niobium oxide catalysts are the specific oxide support and catalyst composition.     

PeliGRIFF,a parallel DEM-DLM/FD direct numerical simulation tool for 3D particulate flows

The problem of particulate flows at moderate to high concentration and finite Reynolds number is addressed by parallel direct numerical simulation. The present contribution is an extension of the work published in Computers & Fluids 38:1608 (2009), where systems of moderate size in a 2D geometry were examined. At the numerical level, the suggested method is inspired by the framework established by Glowinski et al. (Int J Multiph Flow 25:755, 1999) in the sense that their Distributed Lagrange Multiplier/Fictitious Domain (DLM/FD) formulation and their operator-splitting idea are employed. In contrast, particle collisions are handled by an efficient Discrete Element Method (DEM) granular solver, which allows one to consider both smoothly (sphere) and non-smoothly (angular polyhedron) shaped particles. From a computational viewpoint, a basic though efficient strategy has been developed to implement the DLM/FD method in a domain decomposition/distributed fashion. To achieve this goal, the serial code, GRIFF (GRains In Fluid Flow; see Comput Fluids 38:1608–1628, 2009) is upgraded to fully MPI capabilities. The new code, PeliGRIFF (Parallel Efficient Library for GRains in Fluid Flow) is developed under the framework of the fully MPI open-source platform PELICANS. The parallel computing capabilities of PeliGRIFF offer new perspectives in the study of particulate flows and indeed increase the number of particles usually simulated in the literature. Solutions to address new issues raised by the parallelization of the DLM/FD method and assess the scalable properties of the code are proposed. Results on the 2D/3D sedimentation of a significant collection of isometric polygonal/polyhedral particles in a Newtonian fluid with collisions are presented as a validation test and an illustration of the class of particulate flows PeliGRIFF is able to investigate.     

Quantitative determination of the number of surface active sites and the turnover frequency for methanol oxidation over bulk metal vanadates

The present work investigates the number and nature of the surface active sites, selectivity and turnover frequency towards methanol selective oxidation of a series of bulk metal vanadates. The catalysts were synthesized through an organic route and characterized by laser Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and specific surface area analysis (BET). The number of surface active sites (N_s) was determined by measuring the concentration of surface methoxy species adsorbed on the catalysts exposed to an atmosphere of 2000 ppm of methanol in helium at 100 °C. The specific activity values (TOFs) were calculated by normalizing the methanol oxidation reaction rate by the number of surface active sites probed by methanol chemisorption. The comparison of the methanol oxidation products distribution from bulk metal vanadates, pure V₂O₅ and corresponding metal oxides (NiO, MnO, etc.) strongly suggests that the metal vanadate catalysts consist of only surface vanadium oxide sites. The comparison of the TOF values demonstrated that bulk metal vanadates possess similar activity to monolayer vanadium oxide supported catalysts and are more active than bulk metal molybdates for methanol selective oxidation. Moreover, bulk metal vanadates are as active and selective as the commercial MoO₃/Fe₂(MoO₄)₃ catalysts at high methanol conversion.     

Die Bestandteile der Lebensmittel und deren Bestimmung

Ohne ZusammenfassungEinschließlich Beprechungen von Diplomarbeiten und Dissertationen.     

Sonstige organische verbindungen

Ohne Zusammenfassung