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971.
972.
We present an interactive illustrative visualization method inspired by traditional pen‐and‐ink illustration styles. Specifically, we explore how to provide context around DTI fiber tracts in the form of surfaces of the brain, the skull, or other objects such as tumors. These contextual surfaces are derived from either segmentation data or generated using interactive iso‐surface extraction and are rendered with a flexible, slice‐based hatching technique, controlled with ambient occlusion. This technique allows us to produce a consistent and frame‐coherent appearance with precise control over the lines. In addition, we provide context through cutting planes onto which we render gray matter with stippling. Together, our methods not only facilitate the interactive exploration and illustration of brain fibers within their anatomical context but also allow us to produce high‐quality images for print reproduction. We provide evidence for the success of our approach with an informal evaluation with domain experts.  相似文献   
973.

Introduction  

Eddy currents induced by switching of magnetic field gradients can lead to distortions in short echo-time spectroscopy or diffusion weighted imaging. In small bore magnets, such as human head-only systems, minimization of eddy current effects is more demanding because of the proximity of the gradient coil to conducting structures.  相似文献   
974.
Selecting individuals for teams is only rarely supported by IS. Existing systems only consider whether a person has the required technical skills and abilities for a job. Another important aspect is neglected — the match between the person and the team members in terms of interpersonal compatibility. We present a decision support system based on a relational recommendation approach for providing an automated pre-selection of candidates that fit best with future team members. The relational recommender contributes to theory by proposing an IS-supported relational approach to team staffing and to practice by offering time and cost savings for HR professionals.  相似文献   
975.
In this article, the failure behavior of DMOS switches under repetitive clamping stress is shown to be dominated by thermomechanical deformation of the metallization. Electromigration stress is not a significant factor in the failure. This was verified with special stress tests, and the thermomechanical characteristics were furthermore highlighted by FEM simulation. Based on these findings, a novel metallization system that significantly improves the fast temperature cycle reliability is described.  相似文献   
976.
Mesogenic fluids (MFs) may have a great potential for technical applications to increase the energy efficiency and to prevent wear. Aim of the present work was to study a homologous series of mesogenic-like fluids to evaluate the influence of the chemical structure on the tribological behavior. Rheological measurements were additionally performed to correlate the tribological properties with the viscosity and flow behavior. Raman spectroscopy and differential scanning calorimetry measurements were used to characterize the MFs. Furthermore, the surface topography of the wear scar was studied by profilometry. The results were summarized and hence an approach was made to describe the several mechanisms which may lead to the observed tribological results. This work shows that a better understanding of the tribological behavior of these MFs is essential to develop new lubricants.  相似文献   
977.
We discuss the basic concepts of computer vision with stochastic partial differential equations (SPDEs). In typical approaches based on partial differential equations (PDEs), the end result in the best case is usually one value per pixel, the “expected” value. Error estimates or even full probability density functions PDFs are usually not available. This paper provides a framework allowing one to derive such PDFs, rendering computer vision approaches into measurements fulfilling scientific standards due to full error propagation. We identify the image data with random fields in order to model images and image sequences which carry uncertainty in their gray values, e.g. due to noise in the acquisition process. The noisy behaviors of gray values is modeled as stochastic processes which are approximated with the method of generalized polynomial chaos (Wiener-Askey-Chaos). The Wiener-Askey polynomial chaos is combined with a standard spatial approximation based upon piecewise multi-linear finite elements. We present the basic building blocks needed for computer vision and image processing in this stochastic setting, i.e. we discuss the computation of stochastic moments, projections, gradient magnitudes, edge indicators, structure tensors, etc. Finally we show applications of our framework to derive stochastic analogs of well known PDEs for de-noising and optical flow extraction. These models are discretized with the stochastic Galerkin method. Our selection of SPDE models allows us to draw connections to the classical deterministic models as well as to stochastic image processing not based on PDEs. Several examples guide the reader through the presentation and show the usefulness of the framework.  相似文献   
978.
The paper presents a Continuous-Wave(CW)-Radar sensor for high accuracy distance measurements in industrial applications. The usage of radar sensors in industrial scenarios has the advantage of a robust functionality in wet or dusty environments where optical systems reach their limits. This publication shows that accuracies of a few micro-meters are possible with millimeter-wave systems. In addition to distance measurement results the paper describes the sensor concept, the experimental set-up with the measurement process and possibilities to increase the accuracy even further.  相似文献   
979.
980.
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