Electrical conductivity study of defects in zirconium doped yttrium aluminium garnet ceramics

High temperature measurements of conductivity as f(T) of Y3Al5O12 (YAG) doped with 50 ppm Zr in CO/CO2 and H2/H2O gas mixtures show a significant difference in the activation energy (3.54 resp. 1.91 eV) at constant oxygen partial pressure. The sign of the Seebeck coefficient indicates that a H2/H2O atmosphere introduces protons as conducting species into the garnet lattice. Impedance spectroscopy revealed that this is a bulk effect, while the grain boundaries are nearly unaffected by ambient atmosphere. Ionic and electronic conductivity as f(pO2) show that ionic conductivity dominates in the high pO2 regime, while at low pO2 electronic conductivityincreases with pO2-1/5 indicating that either singly or doubly ionised oxygen vacancies or defect clusters appear as prevailing ionic defects

Spectroscopy of Hadrons with b Quarks from Lattice NRQCD

Preliminary results from an extensive lattice calculation of the B, B_c, and \Upsilon spectrum at quenched \beta = 6.0 are presented. The study includes radially and orbitally excited mesons, and baryons containing b quarks. The b quarks are formulated using NRQCD; for light and c quarks, a tadpole-improved clover action is used.Comment: talk given at LATTICE98(heavyqk), 3 pages LaTeX, 2 Postscript figure

Reuse of motion processing for camera stabilization and video coding

The low bit rate of existing video encoders relies heavily on the accuracy of estimating actual motion in the input video sequence. In this paper, we propose a video stabilization and encoding (ViSE) system to achieve a higher coding efficiency through a preceding motion processing stage (to the compression), of which the stabilization part should compensate for vibrating camera motion. The improved motion prediction is obtained by differentiating between the temporal coherent motion and a more noisy motion component which is orthogonal to the coherent one. The system compensates the latter undesirable motion, so that it is eliminated prior to video encoding. To reduce the computational complexity of integrating a digital stabilization algorithm with video encoding, we propose a system that reuses the already evaluated motion vector from the stabilization stage in the compression. As compared to H.264, our system shows a 14% reduction in bit rate yet obtaining an increase of about 0.5 dB in SN

Generalized coordinates on the phase space of Yang-Mills theory

We study the suitability of complex Wilson loop variables as (generalized) coordinates on the physical phase space of $SU(2)$-Yang-Mills theory. To this end, we construct a natural one-to-one map from the physical phase space of the Yang-Mills theory with compact gauge group $G$ to a subspace of the physical configuration space of the complex G^\C-Yang-Mills theory. Together with a recent result by Ashtekar and Lewandowski this implies that the complex Wilson loop variables form a complete set of generalized coordinates on the physical phase space of $SU(2)$-Yang-Mills theory. They also form a generalized canonical loop algebra. Implications for both general relativity and gauge theory are discussed.Comment: TeX, 11pp, revised version (minor clarifications added, Comment after (2.9) inserted); to appear in Class. Quant. Grav

Optimal packages: binding regular polyhedra

Strings on the surface of gift boxes can be modelled as a special kind of cable-and-joint structure. This paper deals with systems composed of idealised (frictionless) closed loops of strings that provide stable binding to the underlying convex polyhedron (‘package’). Optima are searched in both the sense of topology and geometry in finding minimal number of closed loops as well as the minimal (total) length of cables to ensure such a stable binding for simple cases of polyhedra

The influence of CMMI on establishing an architecting process

A large IT company is creating a generic architecting process. Since the company has set an objective to achieve Maturity Level 3 of the Capability Maturity Model Integration (CMMI), the process needs to comply with the relevant requirements set by the CMMI. This paper presents the elicitation of such requirements, and the resulting set of requirements. It analyzes their potential impact on generic architecting processes found in literature. It turns out that many key architectural concepts are at best loosely defined in the CMMI. CMMI is strong in support of the development-related architecting activities, but gives only indirect support for other architecting activities, particularly in a product development context

On creating depth maps from monoscopic video using structure from motion

The depth-image-based rendering technique is a promising technology for three-dimensional television (3D-TV) systems. For such a system, one of the key components is to generate a high-quality per-pixel depth map, particularly for already existing 2D video sequences. This paper proposes a framework for creating the depth map from uncalibrated video sequences of static scenes using the Structure From Motion (SFM) technique. This paper describes the architecture and the main components of the proposed framework. The initial experimental results show that SFM can be an effective way for creating the depth map, or it can be used to refine the depth map created by other methods, for example, the Depth From Cues (DFC) technique

Performance-Efficiency Comparisons of Channel Attention Modules for ResNets

Attention modules can be added to neural network architectures to improve performance. This work presents an extensive comparison between several efficient attention modules for image classification and object detection, in addition to proposing a novel Attention Bias module with lower computational overhead. All measured attention modules have been efficiently re-implemented, which allows an objective comparison and evaluation of the relationship between accuracy and inference time. Our measurements show that single-image inference time increases far more (5–50%) than the increase in FLOPs suggests (0.2–3%) for a limited gain in accuracy, making computation cost an important selection criterion. Despite this increase in inference time, adding an attention module can outperform a deeper baseline ResNet in both speed and accuracy. Finally, we investigate the potential of adding attention modules to pretrained networks and show that fine-tuning is possible and superior to training from scratch. The choice of the best attention module strongly depends on the specific ResNet architecture, input resolution, batch size and inference framework.</p

Adhesion of electrolessly deposited Ni(P) layers on alumina ceramic II. Interface characterization

The interface microstructure and interface chem. of electrolessly deposited Ni(P) on alumina ceramics is studied to obtain insight into the influence of mol. interactions upon the adhesion. Detailed static secondary-ion-mass spectrometry, XPS, Auger electron spectroscopy, and transmission electron microscopy (TEM) analyses have been carried out with samples with various roughness, of which the mech. analyses are described in a companion article. TEM cross-section micrographs showed a close contact between the two phases on a nanometer scale for all sample types. In addn., a 1-2-nm-thick interfacial layer was obsd. This layer consists of nucleation material and compds. from the metalization soln. Fracture surface analyses showed that fracture takes place through this layer, which is therefore considered to be the weak boundary layer in this system. The presence of this weak boundary layer explains the importance of substrate surface roughness and mech. interlocking for the fracture energy. [on SciFinder (R)