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101.
There is limited research on trade-offs in demand between manual and voice interfaces of embedded and portable technologies. Mehler et al. identified differences in driving performance, visual engagement and workload between two contrasting embedded vehicle system designs (Chevrolet MyLink and Volvo Sensus). The current study extends this work by comparing these embedded systems with a smartphone (Samsung Galaxy S4). None of the voice interfaces eliminated visual demand. Relative to placing calls manually, both embedded voice interfaces resulted in less eyes-off-road time than the smartphone. Errors were most frequent when calling contacts using the smartphone. The smartphone and MyLink allowed addresses to be entered using compound voice commands resulting in shorter eyes-off-road time compared with the menu-based Sensus but with many more errors. Driving performance and physiological measures indicated increased demand when performing secondary tasks relative to ‘just driving’, but were not significantly different between the smartphone and embedded systems.

Practitioner Summary: The findings show that embedded system and portable device voice interfaces place fewer visual demands on the driver than manual interfaces, but they also underscore how differences in system designs can significantly affect not only the demands placed on drivers, but also the successful completion of tasks.  相似文献   

102.
DIDS: rapidly prototyping configuration design systems   总被引:3,自引:0,他引:3  
The domain independent design system (DIDS) provides a set of tools for rapidly constructing new configuration design systems from a library of reusable software elements called mechanisms. A DIDS user begins by creating a model of the problem domain and the task to be automated. This includes describing a library of parts from which new artifacts could be configured, optimization and preference criteria, and functionality constraints. DIDS analyzes this input and automatically builds an operational prototype system by selecting and combining mechanisms. DIDS' ability to automate this process is derived from its model of configuration design, which enables reusable mechanisms to be identified and automatically selected based on a problem's characteristics. The use of DIDS is illustrated by showing how DIDS solved an elevator-configuration problem.  相似文献   
103.
A simple thin-layer chromatographic procedure for the quantitative analysis of beer bittering substances is described. In the beers examined, 88–100% of the Brenner determination can be attributed to isohumulones A and B and the ratios of these two isomers show a real variation. Alpha-acids have been shown to be present in our beers. Thin-layer chromatography has also been adapted for analysis of hop resins and with fresh hops excellent agreement has been obtained with the conductometric method of analysis.  相似文献   
104.
The focus of this triple‐blind study was on evaluating the effect of chitosan combined with Dysphania ambrosioides (A) extract on the bone repair process in vivo. In total, 60 male Wistar rats (Rattus norvegicus albinus) weighing between 260 and 270 g were randomly selected for this study and distributed into four groups (n = 15). Group C (chitosan), Group CA5 (chitosan + 5% of D. ambrosioides), Group CA20 (chitosan + 20% of D. ambrosioides), and Group CO (Control‐Blood clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 7, 15, and 30 days, the animals were sedated and sacrificed using the cervical dislocation technique and the tissues were analyzed under optical microscope relative to the following events: inflammatory infiltrate, necrosis, osteoclasts, osteoblasts, fibroblasts, periosteal, and endosteal bone formation. The data were evaluated to verify distribution using the Kolmogorov–Smirnov test, and variance, using the Levene test; as distribution was not normal, data were subjected to the Kruskal–Wallis and Dunn nonparametric tests (p < .05). A significant inflammatory infiltrate was observed in Group CA5 (p = .008) in the time interval of 7 days, and in Group C at 15 (p = .009) and 30 (p = .017) days. Osteoblastic activity was more significant in Group CA20 (p = .027) compared with CA5 in the time interval of 7 days. Group CA20 demonstrated a significantly higher endosteal and periosteal bone formation value in the time interval of 7 (p = .013), 15 (p = .004), and 30 days (p = .008) compared with the other groups. The null hypothesis was refuted, bone regeneration was faster in spheres with an association of chitosan and 20% extract, and complete bone repair occurred clinically at 15 days and histologically at 30 days. The spheres proved to be a promising method for the biostimulation of alveolar bone repair and bone fractures.  相似文献   
105.
新一代微处理器和DSP需要以更低的工作电压提供更大的电流,因此电流检测元件的电阻需要尽可能小,以最大限度地降低电源传导损耗。然而,低电阻电流检测元件产生的斜坡电压较低,这在使用电流模式控制器时,不利于稳定运行。低斜坡电压导致采用电流模式控制方法的开关电源有显著抖动,在很多应用中,开关电源可能变得不稳定。因此,通常由电压模式控制器取而代之,尽管电压模式控制器也有不足之处,并可能出现可靠性问题。本文提出了一种新的电流模式双输出DC/DC降压型控制器,解决了此问题。  相似文献   
106.
One way of sustaining fuel cell technology is using renewable and sustainable energy means provided by biomass. This article explores switchgrass and poplar in a molten carbonate electrolyte direct carbon fuel cell. It investigates their electrochemical conversions and provides results of power density, current density, open circuit voltage (OCV) and other parameters. The biomasses were pyrolysed at 800°C to produce carbon fuels. Biomass carbon fuels were mixed with molten carbonate and subjected to different operating conditions (600–800°C) in the fuel cell. The electrochemical performances of the poplar fuel were better than those experienced with switchgrass fuel. At 800°C the OCV of poplar fuel (1.08?V) has higher output than switchgrass (0.87?V). The peak power density recorded for poplar fuel was 23.91?mW/cm2 while switchgrass fuel was lower at 21.60?mW/cm2. Poplar fuel (81.53?mA/cm2) gave a maximum current density with switchgrass fuel lower at 74.00?mA/cm2.  相似文献   
107.
The relative strength of positive and negative spillovers of urban development is a long-standing and contested issue in regional and development economics, and the search for spread and backwash effects of development in urban core economies goes back at least 50 years. Using data from IMPLAN and the Bureau of Economic Analysis to develop multiregional input–output models, we developed estimates of core–periphery economic interdependence (sales and purchases of goods and services and commuting of workers between the core and the periphery) of the Portland, Oregon, region for 1982 and 2006. We explored whether the changing flows of sales and purchases, spillovers and commuting between 1982 and 2006 suggested a dominance of spread effects or backwash effects. We found increased commuting between periphery and core, decreased core–periphery transactions, and smaller core-to-periphery spillovers and periphery-to-core spillovers in both goods and services. Our findings do not point to a clear dominance of spread or backwash effects. Results showing smaller core-to-periphery and periphery-to-core multipliers/spillovers suggest that spread effects related to trade in goods and services weakened between 1982 and 2006. Our findings of increased commuting are consistent with enhanced spread effects in labor markets.  相似文献   
108.
Various fibrous filter media, including surface filter media, depth filter media, woven and nonwoven filter media, were tested and particle loading capacity was calculated using bench‐scale setup via a new estimation approach which was proposed and experimentally verified with Novick‐Kozeny model. Multi‐element structured arrays (MESAs) developed by our research group were evaluated as well for particle loading capacity and filter lifetime on 24″ × 24″ full scale test rig (based on ASHRAE 52.2 Standard). Effects of varying filter media type, filter depth, pleat count and MESAs' element count on salt particle loading performance were experimentally investigated. The experimental studies showed that nonwoven activated carbon fiber filter media have allowed significantly higher salt particle loading capacity and longer useful lifetime compared to woven or nanofiber entrapped media. Furthermore, MESAs were able to significantly enhance loading capacity for salt particles and useful lifetime due to higher filtration area and lower filtration velocity. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3739–3750, 2016  相似文献   
109.
110.
The behavior of electrospun polyvinyl alcohol (PVA) and polyethylene oxide (PEO) nanofibers embedded with urea is studied as a function of various process parameters. Our results show that three‐dimensional nanofiber networks can be obtained when high concentrations of urea in the solution are used during electrospinning. The nanofibers are characterized using both scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The stability of the nanofiber as a function of electric field has also been studied. The successful formation of three‐dimensional nanofiber networks can open new trends toward applications in fertilizers containing nanofibers in the nanoagricultural field. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39840.  相似文献   
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