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51.
An augmented reality interface to contextual information   总被引:1,自引:0,他引:1  
In this paper, we report on a prototype augmented reality (AR) platform for accessing abstract information in real-world pervasive computing environments. Using this platform, objects, people, and the environment serve as contextual channels to more information. The user??s interest with respect to the environment is inferred from eye movement patterns, speech, and other implicit feedback signals, and these data are used for information filtering. The results of proactive context-sensitive information retrieval are augmented onto the view of a handheld or head-mounted display or uttered as synthetic speech. The augmented information becomes part of the user??s context, and if the user shows interest in the AR content, the system detects this and provides progressively more information. In this paper, we describe the first use of the platform to develop a pilot application, Virtual Laboratory Guide, and early evaluation results of this application.  相似文献   
52.
The aim of this study was to investigate in vitro bioactivity of different thermoplastic biodegradable barrier membranes. Three experimental GBR membranes were fabricated using Poly(epsilon-caprolactone-co-D: ,L-lactide) P(CL/DL-LA) and particulate bioactive glass S53P4 (BAG; granule size 90-315 microm): (A) composite membrane with 60-wt.% of BAG, (B) membrane coated with BAG; and (C) copolymer membrane without BAG. Membranes were immersed in simulated body fluid (SBF), and their surfaces were characterized with SEM, XRD and EDS after 6 and 12 h and after 1, 3, 5, 7, and 14 days. Calcium phosphate (Ca-P) surface formation was observed on both composite membranes (A and B) but not on the copolymer membrane without bioactive glass (C). The Ca-P precipitation appeared to be initiated on the bioactive glass followed by growth of the layer along the polymer surface. In 6-12 h ion dissolution of the bioactive glass led to formation of the silica rich layer on the surface of the exposed glass granules on composite membrane B whereas only small amounts of silica was observed on the polymer surface of the composite membrane A. At 24 h nucleation of Ca-P precipitation was observed, and by 3-5 days membrane surface was covered with a uniform Ca-P layer transforming from amorphous to low crystalline structure. At 7 days composition and structure of the apatite surface resembled the apatite in bone. Once nucleated, the surface topography seemed to have significant effect on the growth of the apatite layer.  相似文献   
53.
Transient receptor potential ankyrin 1 (TRPA1) is a membrane-bound ion channel found in neurons, where it mediates nociception and neurogenic inflammation. Recently, we have discovered that TRPA1 is also expressed in human osteoarthritic (OA) chondrocytes and downregulated by the anti-inflammatory drugs aurothiomalate and dexamethasone. We have also shown TRPA1 to mediate inflammation, pain, and cartilage degeneration in experimental osteoarthritis. In this study, we investigated the role of TRPA1 in joint inflammation, focusing on the pro-inflammatory cytokine interleukin-6 (IL-6). We utilized cartilage/chondrocytes from wild-type (WT) and TRPA1 knockout (KO) mice, along with primary chondrocytes from OA patients. The results show that TRPA1 regulates the synthesis of the OA-driving inflammatory cytokine IL-6 in chondrocytes. IL-6 was highly expressed in WT chondrocytes, and its expression, along with the expression of IL-6 family cytokines leukemia inhibitory factor (LIF) and IL-11, were significantly downregulated by TRPA1 deficiency. Furthermore, treatment with the TRPA1 antagonist significantly downregulated the expression of IL-6 in chondrocytes from WT mice and OA patients. The results suggest that TRPA1 is involved in the upregulation of IL-6 production in chondrocytes. These findings together with previous results on the expression and functions of TRPA1 in cellular and animal models point to the role of TRPA1 as a potential mediator and novel drug target in osteoarthritis.  相似文献   
54.
Generative encodings have the potential of improving the performance of evolutionary algorithms. In this work we apply parametric L-systems, which can be described as developmental recipes, to evolutionary topology optimization of widely studied two-dimensional steady-state heat conduction problems. We translate L-systems into geometries using the turtle interpretation, and evaluate their objective functions, i.e. average and maximum temperatures, using the Finite Volume Method (FVM). The method requires two orders of magnitude fewer function evaluations, and yields better results in 10 out of 12 tested optimization problems (the result is statistically significant), than a reference method using direct encoding. Further, our results indicate that the method yields designs with lower average temperatures than the widely used and well established SIMP (Solid Isotropic Material with Penalization) method in optimization problems where the product of volume fraction and the ratio of high and low conductive material is less or equal to 1. Finally, we demonstrate the ability of the methodology to tackle multi-objective optimization problems with relevant temperature and manufacturing related objectives.  相似文献   
55.
Management of safety is always based on underlying models or theories of organization, human behavior and system safety. The aim of the article is to review and describe a set of potential biases in these models and theories. We will outline human and organizational biases that have an effect on the management of safety in four thematic areas: beliefs about human behavior, beliefs about organizations, beliefs about information and safety models. At worst, biases in these areas can lead to an approach where people are treated as isolated and independent actors who make (bad) decisions in a social vacuum and who pose a threat to safety. Such an approach aims at building barriers and constraints to human behavior and neglects the measures aiming at providing prerequisites and organizational conditions for people to work effectively. This reductionist view of safety management can also lead to too drastic a strong separation of so-called human factors from technical issues, undermining the holistic view of system safety. Human behavior needs to be understood in the context of people attempting (together) to make sense of themselves and their environment, and act based on perpetually incomplete information while relying on social conventions, affordances provided by the environment and the available cognitive heuristics. In addition, a move toward a positive view of the human contribution to safety is needed. Systemic safety management requires an increased understanding of various normal organizational phenomena - in this paper discussed from the point of view of biases - coupled with a systemic safety culture that encourages and endorses a holistic view of the workings and challenges of the socio-technical system in question.  相似文献   
56.
Abstract

Particle deposition in the human respiratory tract is considered to have negative effects on human health. The lung deposited surface area (LDSA) is an important metric developed to assess the negative health effects of particles deposited in the alveolar region of the human respiratory tract. The measurement of the LDSA is frequently based on the detection of the electrical current carried by diffusion charged particles. Various conversion factors can be used to convert the electric current into LDSA concentration with relatively good accuracy up to the size about 300-600?nm. In this study, we introduce stage-specific LDSA conversion factors for electrical low pressure impactor (ELPI+) data, which enable accurate and real time LDSA concentration and LDSA size distribution measurements in the particle size range from 6?nm to 10?µm. This wide size range covers most of the alveolar deposition of particles, which has not been possible previously by electrical methods. Also, the conversion factors for tracheobronchial and head airways particle surface area deposition were determined, and the stage-specific conversion factors were compared with the single-factor data conversion method. Furthermore, the stage-specific calibration was tested against real-world particle size distributions by simulations and against laboratory-generated aerosols. Particles larger than 300?nm were observed to significantly affect the total LDSA concentration. Stage-specific conversion factors are especially required while measuring aerosols containing larger particles or when considering the surface area deposition in the tracheobronchial region and head airways. The method and the conversion factors introduced in this study can be used to monitor LDSA concentrations reliably in various environments containing particles in different size ranges.

Copyright © 2020 American Association for Aerosol Research  相似文献   
57.
There is a considerable amount of discussion, but still no consensus, about which indicator should be used to measure innovation. To participate in this debate, a unique innovation database, SFINNO, is introduced. Innovation counts from the database are used as the baseline, to which individual proxy indicators (patent- and research and development statistics) of innovation and innovation indexes, constructed here with principal component analysis, are compared. The local administrative units of Finland serve as the regional units benchmarked. The study results show that innovation is a complex phenomenon which cannot be entirely explained through the use of proxy statistics, as the linkages between innovation input- and output-indicators are fuzzy. We also show that the strength of these linkages varies by field of technology. Furthermore, different innovation measures produce highly divergent rankings when they are used as benchmarking tools of regional innovative performance. Although the produced innovation indexes perform slightly better, their superiority is marginal. Therefore, caution should be taken before drawing too drastic policy conclusions depending on a single measure of regional innovative performance.  相似文献   
58.
Human tankyrases are attractive drug targets, especially for the treatment of cancer. We identified a set of highly potent tankyrase inhibitors based on a 2‐phenyl‐3,4‐dihydroquinazolin‐4‐one scaffold. Substitutions at the para position of the scaffold′s phenyl group were evaluated as a strategy to increase potency and improve selectivity. The best compounds displayed single‐digit nanomolar potencies, and profiling against several human diphtheria‐toxin‐like ADP‐ribosyltransferases revealed that a subset of these compounds are highly selective tankyrase inhibitors. The compounds also effectively inhibit Wnt signaling in HEK293 cells. The binding mode of all inhibitors was studied by protein X‐ray crystallography. This allowed us to establish a structural basis for the development of highly potent and selective tankyrase inhibitors based on the 2‐phenyl‐3,4‐dihydroquinazolin‐4‐one scaffold and outline a rational approach to the modification of other inhibitor scaffolds that bind to the nicotinamide site of the catalytic domain.  相似文献   
59.
Laminated steel has been implemented in vehicle structures by several automotive manufacturers to reduce in-cabin noise. This study provides an understanding of how the adhesion between the steel skin and the viscoelastic polymer core affects laminate formability. Material properties, including peel strength, shear strength, and tensile strength were determined. The presence of the viscoelastic core was found to slightly reduce tensile properties of the laminate compared to the skin sheet. Forming limit diagrams were also determined. These indicated that the viscoelastic core properties can significantly affect formability of laminated steel compared to that of solid steel sheet. In general, the formability of laminated steel was found to be similar to or less than that of the much thinner skin sheet material, which indicates that its formability should be less than that of solid steel of the same gauge. This article was presented at Materials Science & Technology 2007, Automotive and Ground Vehicles symposium held September 16-20, 2007, in Detroit, MI.  相似文献   
60.
Software defined radios (SDR) wideband mobile terminals must be capable of data processing while consuming low power and keeping the design and manufacturing costs as low as possible. SDR can combine high performance signal processing and flexibility, but power efficiency of SDR nodes is an issue that needs to be addressed. Analysis of power consumption for various target technologies is challenging, since each technology typically contains its own benchmarking tools and thus, results are not comparable. In this paper, we illustrate how the GroundHog2009 benchmark suite, designed to be platform independent, can be used to evaluate power dissipation of four modern FPGAs and one microcontroller. We also introduce a generic RTL library for the GroundHog2009 design cases and test bench infra-structure to make the toolset usage easy. In addition, we show that power can be saved by using clock management, available on one of the FGPA-boards. The power savings range from 38 to 1,150?%.  相似文献   
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