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71.
A taxonomy for and analysis of multi-person-display ecosystems 总被引:2,自引:2,他引:0
Interactive displays are increasingly being distributed in a broad spectrum of everyday life environments: they have very
diverse form factors and portability characteristics, support a variety of interaction techniques, and can be used by a variable
number of people. The coupling of multiple displays creates an interactive “ecosystem of displays”. Such an ecosystem is suitable for particular social
contexts, which in turn generates novel settings for communication and performance and challenges in ownership. This paper
aims at providing a design space that can inform the designers of such ecosystems. To this end, we provide a taxonomy that
builds on the size of the ecosystem and on the degree of individual engagement as dimensions. We recognize areas where physical
constraints imply certain kinds of social engagement, versus other areas where further work on interaction techniques for
coupling displays can open new design spaces. 相似文献
72.
Many time-critical applications require predictable performance in the presence of failures. This paper considers a distributed system with independent periodic tasks which can checkpoint their state on some reliable medium in order to handle failures. The problem of preemptively scheduling a set of such tasks is discussed where every occurrence of a task has to be completely executed before the next occurrence of the same task can start. Efficient scheduling algorithms are proposed which yield sub-optimal schedules when there is provision for fault-tolerance. The performance of the solutions proposed is evaluated in terms of the number of processors and the cost of the checkpoints needed. Moreover, analytical studies are used to reveal interesting trade-offs associated with the scheduling algorithms.This work has been supported by grants from the Italian Ministero dell'Università e della Ricerca Scientifica e Tecnologica and the Consiglio Nazionale delle Ricerche-Progetto Finalizzato Sistemi Informatici e Calcolo Parallelo. 相似文献
73.
Qi Jiyang Gao Yan Hu Yao Wang Xinggang Liu Xiaoyu Bai Xiang Belongie Serge Yuille Alan Torr Philip H. S. Bai Song 《International Journal of Computer Vision》2022,130(8):2022-2039
International Journal of Computer Vision - Can our video understanding systems perceive objects when a heavy occlusion exists in a scene? To answer this question, we collect a large-scale dataset... 相似文献
74.
Joan C. Lo Gerald J. Beck George A. Kaysen Christopher T. Chan Alan S. Kliger Michael V. Rocco Glenn M. Chertow for the FHN Study 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(2):190-196
Introduction: End‐stage renal disease is associated with elevations in circulating prolactin concentrations, but the association of prolactin concentrations with intermediate health outcomes and the effects of hemodialysis frequency on changes in serum prolactin have not been examined. Methods: The FHN Daily and Nocturnal Dialysis Trials compared the effects of conventional thrice weekly hemodialysis with in‐center daily hemodialysis (6 days/week) and nocturnal home hemodialysis (6 nights/week) over 12 months and obtained measures of health‐related quality of life, self‐reported physical function, mental health and cognition. Serum prolactin concentrations were measured at baseline and 12‐month follow‐up in 70% of the FHN Trial cohort to examine the associations among serum prolactin concentrations and physical, mental and cognitive function and the effects of hemodialysis frequency on serum prolactin. Findings: Among 177 Daily Trial and 60 Nocturnal Trial participants with baseline serum prolactin measurements, the median serum prolactin concentration was 65 ng/mL (25th–75th percentile 48–195 ng/mL) and 81% had serum prolactin concentrations >30 ng/mL. While serum prolactin was associated with sex (higher in women), we observed no association between baseline serum prolactin and age, dialysis vintage, and baseline measures of physical, mental and cognitive function. Furthermore, there was no significant effect of hemodialysis frequency on serum prolactin in either of the two trials. Discussion: Serum prolactin concentrations were elevated in the large majority of patients with ESRD, but were not associated with several measures of health status. Circulating prolactin levels also do not appear to decrease in response to more frequent hemodialysis over a one‐year period. 相似文献
75.
76.
Unraveling Unprecedented Charge Carrier Mobility through Structure Property Relationship of Four Isomers of Didodecyl[1]benzothieno[3,2‐b][1]benzothiophene 下载免费PDF全文
Yusuke Tsutsui Guillaume Schweicher Basab Chattopadhyay Tsuneaki Sakurai Jean‐Baptiste Arlin Christian Ruzié Almaz Aliev Artur Ciesielski Alan R. Kennedy Vincent Lemaur Yoann Olivier Rachid Hadji Lionel Sanguinet Frédéric Castet Silvio Osella Dmytro Dudenko David Beljonne Jérôme Cornil Paolo Samorì Shu Seki Yves H. Geerts 《Advanced materials (Deerfield Beach, Fla.)》2016,28(33):7106-7114
77.
Étude O'Neel‐Judy Dylan Nicholls John Castañeda John G. Gibbs 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(32)
Using a dynamic fabrication process, hybrid, photoactivated microswimmers made from two different semiconductors, titanium dioxide (TiO2) and cuprous oxide (Cu2O) are developed, where each material occupies a distinct portion of the multiconstituent particles. Structured light‐activated microswimmers made from only TiO2 or Cu2O are observed to be driven in hydrogen peroxide and water most vigorously under UV or blue light, respectively, whereas hybrid structures made from both of these materials exhibit wavelength‐dependent modes of motion due to the disparate responses of each photocatalyst. It is also found that the hybrid particles are activated in water alone, a behavior which is not observed in those made from a single semiconductor, and thus, the system may open up a new class of fuel‐free photoactive colloids that take advantage of semiconductor heterojunctions. The TiO2/Cu2O hybrid microswimmer presented here is but an example of a broader method for inducing different modes of motion in a single light‐activated particle, which is not limited to the specific geometries and materials presented in this study. 相似文献
78.
Percutaneous US guided nephrostomy is the simplest and most direct technique to drain an obstructed kidney. The indications are included in two groups: temporary drainage and permanent drainage; the former is indicated in the non endoscopically superable ureteral obstruction, in pyonephrosis, in pregnant women and in transplanted kidneys (due to the easier access), the latter is exclusively reserved to neoplastic obstructions. The only real contraindication to the method, besides a documented allergy to local anaesthetics, is represented by a severe coagulopathy. Positioning techniques are the "one shot" technique, in which dilation and positioning are synchronous (it can avoid fluoroscopy but it is more traumatic) and angiographic derived Seldinger's technique, that utilizes fluoroscopy and an instrumentation including a guidewire and a set of Amplatz dilators. Complications are due to the access route; the choice of an intercostal access is always inadvisable, due to the risk of pneumothorax or pulmonary injury; the most frequent complications are vascular (hemorrhage, retroperitoneal hematoma) and usually well controlled; more severe lesions (renal artery laceration and arteriovenous fistula) may require intervention or embolization, but the incidence of nephrectomies due to vascular injury accounts for one per thousand. 相似文献
79.
We demonstrate a microfluidic continuous-flow protein separation process in which silica-coated superparamagnetic nanoparticles
interact preferentially with hemoglobin in a mixture with bovine serum albumin, and the resulting hemoglobin-nanoparticle
aggregates are recovered online using magnetophoresis. We present detailed modeling and analysis of this process yielding
quantitative estimates of the recovery of both proteins, validated by experiments. While several previous studies utilize
an average particle size in modeling magnetophoretic particle trajectories or process design, in this study we emphasize the
importance of accounting for particle size distributions in calculating particle recovery, and therefore in estimating separation
efficiency. We combine experimentally measured size distributions of protein-nanoparticle aggregates with simulations of particle
trajectories and provide a simple analytical method to calculate the efficiency of separation at various flow speeds, which
fully accounts for heterogeneity in particle sizes. Our method can potentially be used for affinity based biomolecular separations
at both analytical and preparative scales by exploiting well-established techniques to functionalize nanoparticle surfaces
with selective ligands. Further, the modeling methodology presented here may be applied to provide better estimates of particle
recovery in a broad range of magnetophoretic separation processes involving heterogeneity in particle sizes. 相似文献
80.
Anush?Krishna?MoorthyEmail author Alan?Conrad?Bovik 《Multimedia Tools and Applications》2011,51(2):675-696
Creating algorithms capable of predicting the perceived quality of a visual stimulus defines the field of objective visual
quality assessment (QA). The field of objective QA has received tremendous attention in the recent past, with many successful
algorithms being proposed for this purpose. Our concern here is not with the past however; in this paper we discuss our vision
for the future of visual quality assessment research. We first introduce the area of quality assessment and state its relevance.
We describe current standards for gauging algorithmic performance and define terms that we will use through this paper. We
then journey through 2D image and video quality assessment. We summarize recent approaches to these problems and discuss in
detail our vision for future research on the problems of full-reference and no-reference 2D image and video quality assessment.
From there, we move on to the currently popular area of 3D QA. We discuss recent databases, algorithms and 3D quality of experience.
This yet-nascent technology provides for tremendous scope in terms of research activities and we summarize each of them. We
then move on to more esoteric topics such as algorithmic assessment of aesthetics in natural images and in art. We discuss
current research and hypothesize about possible paths to tread. Towards the end of this article, we discuss some other areas
of interest including high-definition (HD) quality assessment, immersive environments and so on before summarizing interesting
avenues for future work in multimedia (i.e., audio-visual) quality assessment. 相似文献