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Ralph Barthel Kerstin Leder Mackley Andrew Hudson-Smith Angelina Karpovich Martin de Jode Chris Speed 《Personal and Ubiquitous Computing》2013,17(2):321-333
The interdisciplinary Tales of Things and electronic Memory (TOTeM) project investigates new contexts for augmenting things with stories in the emerging culture of the Internet of Things (IoT). Tales of Things is a tagging system which, based on two-dimensional barcodes (also called Quick Response or QR codes) and Radio Frequency Identification (RFID) technology, enables the capturing and sharing of object stories and the physical linking to objects via read and writable tags. Within the context of our study, it has functioned as a technology probe which we employed with the aim to stimulate discussion and identify desire lines that point to novel design opportunities for the engagement with personal and social memories linked to everyday objects. In this paper, we discuss results from fieldwork with different community groups in the course of which seemingly any object could form the basis of a meaningful story and act as entry point into rich inherent ‘networks of meaning’. Such networks of meaning are often solely accessible for the owner of an object and are at risk of getting lost as time goes by. We discuss the different discourses that are inherent in these object stories and provide avenues for making these memories and meaning networks accessible and shareable. This paper critically reflects on Tales of Things as an example of an augmented memory system and discusses possible wider implications for the design of related systems. 相似文献
64.
A. Ern I. Mozolevski L. Schuh 《Computer Methods in Applied Mechanics and Engineering》2010,199(23-24):1491-1501
We design and investigate a sequential discontinuous Galerkin method to approximate two-phase immiscible incompressible flows in heterogeneous porous media with discontinuous capillary pressures. The nonlinear interface conditions are enforced weakly through an adequate design of the penalties on interelement jumps of the pressure and the saturation. An accurate reconstruction of the total velocity is considered in the Raviart–Thomas(–Nédélec) finite element spaces, together with diffusivity-dependent weighted averages to cope with degeneracies in the saturation equation and with media heterogeneities. The proposed method is assessed on one-dimensional test cases exhibiting rough solutions, degeneracies, and capillary barriers. Stable and accurate solutions are obtained without limiters. 相似文献
65.
Which objects and animals are children willing to accept as referents for words they know? To answer this question, the authors assessed early word comprehension using the preferential looking task. Children were shown 2 stimuli side by side (a target and a distractor) and heard the target stimulus named. The target stimulus was either a typical or an atypical exemplar of the named category. It was predicted that children first connect typical examples with the target name and broaden the extension of the name as they get older to include less typical examples. Experiment 1 shows that when targets are named, 12-month-olds display an increase in target looking for typical but not atypical targets whereas 24-month-olds display an increase for both. Experiment 2 shows that 18-month-olds display a pattern similar to that of 24-month-olds. Implications for the early development of word comprehension are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
The order of an electromagnetics algorithm or code is defined by the rate at which the CPU time, and memory requirements CCPU=O(fα) and Cm=O(fβ ), respectively-grow with frequency. Knowledge of this information helps in the prediction of computer-run times and memory requirements for problems of interest. This paper presents a methodology for determining the computational and memory orders of a code. These results are presented for a finite-volume time-domain (FVTD) code and for a method-of-moments (MoM) code. Computer-resource requirements are plotted for computer runs that calculate the bistatic radar cross section (RCS) for spheres of different electrical sizes, within a set error level from the Mie-series solution. These plots are used to calculate the computational and memory orders of the codes 相似文献
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Inverse-synthetic-aperture-radar (ISAR) images of radar targets are useful for target identification, visualization, and the analysis of scattering centers. The major advantage of bistatic over monostatic-ISAR imaging is the reduction, in the number of computed incident angles, from hundreds to one. This advantage has already been demonstrated for a physical theory of diffraction (PTD) code, XPATCH. The bistatic-imaging technique can be extended to scattering data obtained from any time-accurate or iterative method, including low-frequency algorithms. This paper presents images from data obtained with a finite-volume time-domain (FVTD) code. It also provides relations between (1) the range and resolution of the bistatic scattering data in the Fourier domain, and (2) the pixel resolution and image extent in the physical domain for the down-range and cross-range directions. A tapering function is applied in the Fourier domain, to dampen ringing effects. Results are shown for a trapezoidal plate, a cone-sphere, and a square-aperture cavity 相似文献
69.
Kerstin Hannemann Volker Puchta Ernst Simon Herta Ziegler Gunter Ziegler Gerhard Spiteller 《Lipids》1989,24(4):296-298
The observation that F-acids (1) occur in rat chow initiated a search for F-acids in human diet. We observed that the amount
of F-acids with a pentyl side chain in α-position taken up with a one-day diet correlates well with the amount of excreted
degradation products, the pentyl urofuran acids (2), (3) and (4). Therefore it can be concluded that F-acids with a pentyl
side chain are not produced in the human body but are introduced through the diet. The origin of F-acids carrying an α-propyl
side chain is less clear. The amount of propyl-urofuran acids (2) and (3) excreted in urine was found in one case out of three
to be five times higher than the amount of F-acids carrying a propyl group in α-position taken up by the diet. Therefore,
it can presently not be excluded that a portion of the propyl F-acids is produced by the body.
F-acids found in human food are mainly introduced into the body by vegetables and fruits. F-acids were found also in birch
leaves in considerable amounts, as well as in grasses, dandelion and clover leaves. Thus, we can conclude that F-acids are
common constituents of plants. 相似文献
70.
Matt Harrington Michael Lin Kerstin N. Nordstrom Wolfgang Losert 《Granular Matter》2014,16(2):185-191
Many recent advances in the study of granular media have stemmed from the improved capability to image and track individual grains in two and three dimensions. While two-dimensional systems readily yield both translational and rotational motion, a challenge in three-dimensional experiments is the tracking of rotational motion of isotropic particles. We propose an extension of the refractive index matched scanning technique as a method of measuring individual particle rotation. Initial measurements indicate that shear-driven rotational motion may stem from gear-like motion within the shear zone. 相似文献