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81.
Personalcasting: Tailored Broadcast News   总被引:1,自引:0,他引:1  
Broadcast news sources and newspapers provide society with the vast majority of real-time information. Unfortunately, cost efficiencies and real-time pressures demand that producers, editors, and writers select and organize content for stereotypical audiences. In this article we illustrate how content understanding, user modeling, and tailored presentation generation promise personalcasts on demand. Specifically, we report on the design and implementation of a personalized version of a broadcast news understanding system, MITRE’s Broadcast News Navigator (BNN), that tracks and infers user content interests and media preferences. We report on the incorporation of Local Context Analysis to both expand the user’s original query to the most related terms in the corpus, as well as to allow the user to provide interactive feedback to enhance the relevance of selected newsstories. We describe an empirical study of the search for stories on ten topics from a video corpus. By personalizing both the selection of stories and the form in which they are delivered, we provide users with tailored broadcast news. This individual news personalization provides more fine-grained content tailoring than current personalized television program level recommenders and does not rely on externally provided program metadata.  相似文献   
82.
There are countless beliefs about the power of music during driving. The last thing one would think about is: how safe is it to listen or sing to music? Unfortunately, collisions linked to music devices have been known for some time; adjusting the radio controls, swapping tape-cassettes and compact-discs, or searching through MP3 files, are all forms of distraction that can result in a near-crash or crash. While the decrement of vehicular performance can also occur from capacity interference to central attention, whether or not music listening is a contributing factor to distraction is relatively unknown. The current study explored the effects of driver-preferred music on driver behavior. 85 young-novice drivers completed six trips in an instrumented Learners Vehicle. The study found that all participants committed at-least 3 driver deficiencies; 27 needed a verbal warning/command and 17 required a steering or braking intervention to prevent an accident. While there were elevated positive moods and enjoyment for trips with driver-preferred music, this background also produced the most frequent severe driver miscalculations and inaccuracies, violations, and aggressive driving. However, trips with music structurally designed to generate moderate levels of perceptual complexity, improved driver behavior and increased driver safety. The study is the first within-subjects on-road high-dose double-exposure clinical-trial investigation of musical stimuli on driver behavior.  相似文献   
83.
Process waters obtained from hydrothermal carbonization (HTC) of wheat straw, a biogas digestate derived thereof, and four woody biomass feedstocks were quantified regarding the total organic carbon (TOC) and selected organic compounds. HTC runs revealed that TOC loads were largely unaffected by process severity or type of feedstock whereas the C2–C6 fatty acids, determined by GC, displayed clear effects of temperature and feedstock. HPLC demonstrated simultaneously the initial increase and subsequent consumption of cellulose‐derived furfural and 5‐hydroxymethylfurfural as well as the increase of the lignin‐derived 2‐methoxyphenol. 2‐Methylbenzofuran, an example for a substance potentially harmful to aquatic biota, was observed in high concentration in the HTC liquor from wheat straw‐based feedstocks.  相似文献   
84.
85.
Anecdotal accounts of water-filled containers starting fires by focusing sunlight occasionally appear in the popular press, typically as curiosity items. This paper demonstrates the use of optical modeling tools and methodologies to explore situations under which water-filled containers can concentrate sunlight sufficiently to start fires, and proves the existence of a real hazard with an experimental demonstration.  相似文献   
86.
Articular cartilage defects are a significant source of pain, have limited ability to heal, and can lead to the development of osteoarthritis. However, a surgical solution is not available. To tackle this clinical problem, non-degradable implants capable of carrying mechanical load immediately after implantation and for the duration of implantation, while integrating with the host tissue, may be viable option. But integration between articular cartilage and non-degradable implants is not well studied. Our objective was to assess the in vivo performance of a novel macroporous, nondegradable, polyvinyl alcohol construct. We hypothesized that matrix generation within the implant would be enhanced with partial digestion of the edges of articular cartilage. Our hypothesis was tested by randomizing an osteochondral defect created in the trochlea of 14 New Zealand white rabbits to treatment with: (i) collagenase or (ii) saline, prior to insertion of the implant. At 1 and 3-month post-operatively, the gross morphology and histologic appearance of the implants and the surrounding tissue were assessed. At 3 months, the mechanical properties of the implant were also quantified. Overall, the hydrogel implants performed favorably; at all time-points and in all groups the implants remained well fixed, did not cause inflammation or synovitis, and did not cause extensive damage to the opposing articular cartilage. Regardless of treatment with saline or collagenase, at 1 month post-operatively implants from both groups had a contiguous interface with adjacent cartilage and were populated with chondrocyte-like cells. At 3 months fibrous encapsulation of all implants was evident, there was no difference between area of aggrecan staining in the collagenase versus saline groups, and implant modulus was similar in both groups; leading us to reject our hypothesis. In summary, a porous PVA osteochondral implant remained well fixed in a short term in vivo osteochondral defect model; however, matrix generation within the implant was not enhanced with partial digestion of adjacent articular cartilage.  相似文献   
87.
ABSTRACT

Occupancy patterns are necessary to estimate energy demand and evaluate thermal comfort in households. Because of this, many European countries are developing representative domestic schedules to replace outdated criteria. This paper evaluates the state of knowledge of UK domestic occupancy patterns and develops new domestic occupancy profiles for England. The presented research (1) characterizes methods for collecting occupancy data and inferring patterns; (2) identifies and assesses the quality of categories of occupancy patterns used in building simulation; and (3) develops updated occupancy profiles. A systematic scoping review identified social and monitoring surveys as the most deployed data-collection methods. A systematic literature review also established that the occupancy categories most frequently used in UK building simulation are (a) a family with dependent children where the parents work full time; and (b) a retired elderly couple who spend most of their time indoors. The interview sample from the English Housing Survey 2014–15 was used to map household typologies. Results show that categories (a) and (b) combined amount to only 19% of England’s households, which suggest models are over-reliant on these groups. Considering this result, the paper develops occupancy patterns for England derived from 2015 UK Time Use Survey diaries for each household typology previously identified.  相似文献   
88.
The ADtree, a data structure useful for caching sufficient statistics, has been successfully adapted to grow lazily when memory is limited and to update sequentially with an incrementally updated dataset. However, even these modified forms of the ADtree still exhibit inefficiencies in terms of both space usage and query time, particularly on datasets with very high dimensionality and with high-arity features. We propose four modifications to the ADtree, each of which can be used to improve size and query time under specific types of datasets and features. These modifications also provide an increased ability to precisely control how an ADtree is built and to tune its size given external memory or speed requirements.  相似文献   
89.
ABSTRACT

This study sought to identify and quantify the effects of environmental test parameters on the mucoadhesivity of a propranolol tablet. Their effects on Maximum Detachment Force (MDF) measurements were evaluated using a Box-Behnken design matrix. Prehydration time (PT) had a statistically significant negative main effect while contact force (CF) had no significant effect on in vitro MDF measurements. While contact time (CT) had no significant main or quadratic effects, it had a positive interaction effect with PT. The mathematical model was statistically validated and a PT of 3.5 min and a CT of 5 min was proposed for mucoadhesion testing by the tensile method during formulation optimization.  相似文献   
90.
Single‐walled carbon nanotubes (SWCNTs) dispersed in N‐methylpyrrolidone (NMP) were functionalized by addition of polystyryl radicals from 2,2,6,6‐tetramethyl‐1‐piperidinyloxy‐ended polystyrene (SWCNT‐g‐PS). The amount of polystyrene grafted to the nanotubes was in the range 20‐25 wt% irrespective of polystyrene number‐average molecular weight ranging from 2270 to 49 500 g mol?1. In Raman spectra the ratios of D‐band to G‐band intensity were similar for all of the polystyrene‐grafted samples and for the starting SWCNTs. Numerous near‐infrared electronic transitions of the SWCNTs were retained after polymer grafting. Transmission electron microscopy images showed bundles of SWCNT‐g‐PS of various diameters with some of the polystyrene clumped on the bundle surfaces. Composites of SWCNT‐g‐PS in a commercial‐grade polystyrene were prepared by precipitation of mixtures of the components from NMP into water, i.e. the coagulation method of preparation. Electrical conductivities of the composites were about 10?15 S cm?1 and showed no percolation threshold with increasing SWCNT content. The glass transition temperature (Tg) of the composites increased at low filler loadings and remained constant with further nanotube addition irrespective of the length and number of grafted polystyrene chains. The change of heat capacity (ΔCp) at Tg decreased with increasing amount of SWCNT‐g‐PS of 2850 g mol?1, but ΔCp changed very little with the amount of SWCNT‐g‐PS of higher molecular weight. The expected monotonic decrease in ΔCp coupled with the plateau behavior of Tg suggests there is a limit to the amount that Tg of the matrix polymer can increase with increasing amount of nanotube filler. Copyright © 2012 Society of Chemical Industry  相似文献   
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