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91.
Ben Shneiderman Catherine Plaisant Rodrigo Botafogo Don Hopkins William Weiland 《New Review of Hypermedia and Multimedia》2013,19(2):101-117
Since browsing hypertext can present a formidable cognitive challenge, user interface design plays a major role in determining acceptability. In the Unix workstation version of Hyperties, a research-oriented prototype, we focussed on design features that facilitate browsing. We first give a general overview of Hyperties and its markup language. Customizable documents can be generated by the conditional text feature that enables dynamic and selective display of text and graphics. In addition we present: — an innovative solution to link identification: pop-out graphical buttons of arbitrary shape. — application of pie menus to permit low cognitive load actions that reduce the distraction of common actions, such as page turning or window selection. — multiple window selection strategies that reduce clutter and housekeeping effort. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and actions could be done rapidly, allowing users to concentrate on the contents. 相似文献
92.
The effects of conventional heating (C) or ohmic heating (O) treatment on the degradation of sugar and ascorbic acid (AA) were evaluated in chunky fruit desserts prepared with apple puree (Golden Delicious var.) and chunky peach (Panavi var.) pieces. Concentrations of 5-HMF, furfural (F), 3-hydroxy-2-pyrone (3H2P) and 2-furoic acid (FA) were determined to assess the importance of oxidative and/or thermal reactions during processing. Depending on the thermal processing, 5-HMF and F levels in samples ranged from not detected to 3260 and from not detected to 570 μg/100 g FW respectively. Production of 3H2P and FA ranged from 480 to 2670 and from 84 to 420 μg/100 g FW respectively. Results showed that the impact of final heating treatment on the formation of AA degradation products (3H2P and FA) was minor, if any. Thus, AA degradation during apple products processing mainly depended on oxidative reactions pathway. Likewise, ohmic heating processing had very little effect on the formation of 5-HMF and F, in opposite to conventional heating. 相似文献
93.
Yi-Ming Zhao Shikha Ojha Catherine M. Burgess Da-Wen Sun Brijesh K. Tiwari 《International Journal of Food Science & Technology》2021,56(2):721-732
This study aimed to evaluate the influence of plasma treatment time, bacterial exposure time to PAW and bacterial species on the inactivation efficacy of plasma-activated water (PAW), with additional investigation of the inactivation mechanisms of PAW. Six bacterial species, including Listeria innocua, Staphyloccus aureus, Escherichia coli, Pseudomonas fluorescens, Shewanella putrefaciens and Aeromonas hydrophila were selected as the representative bacteria. The initial bacterial concentration was around 7 log CFU ml−1 after mixing with PAW, and the inactivation efficacy was measured after different exposure times during the 4 °C storage. Scanning electron microscopy (SEM) images of the bacteria after PAW treatment were carried out to inspect the cell structure damage, and physicochemical properties of PAW, including pH, conductivity and long-living reactive species of H2O2, , and , were examined. The results showed that the inactivation efficacy of PAW was positively correlated with plasma treatment time and bacterial exposure time, and for the species examined in this study, the Gram-negative species were more sensitive to PAW than the Gram-positive species. Cell structure damage, including shrinkage, distortion, or holes, was observed after PAW treatment. The pH of PAW was acidified to 2.5–2.9, and conductivity was significantly increased to 518.0 μs cm−1. and H2O2 were reduced during the 48 h storage, while an increased concentration was observed for . This study demonstrated that the processing parameters of plasma treatment time, exposure time and characteristics of bacteria can significantly affect the inactivation efficacy of PAW. 相似文献
94.
Joo Hee Kim Seok Hyun Nam Catherine W. Rico Mi Young Kang 《International Journal of Food Science & Technology》2012,47(6):1176-1182
The antioxidative and anti‐allergic activities of fresh and aged black garlic extracts were investigated. The garlic samples were extracted with 70% ethanol (v/v) and the total phenolic content was measured. The antioxidant capacity of extracts was assessed by determining the scavenging activities on 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals, ferricyanide reducing power, ferrous ion‐chelating ability and inhibitory effect on linoleic acid peroxidation. The anti‐allergic activity of extracts was analysed by measuring their inhibitory effects against β‐hexosaminidase release. The aged black garlic exhibited significantly higher phenolic content and greater antioxidative activity than fresh garlic. Both garlic extracts showed strong antioxidant capacity in a dose‐dependent manner. On the other hand, a considerably higher suppression of β‐hexosaminidase release was found in fresh garlic extract at lower concentration compared with that of the black garlic. Results of this study illustrate that ageing of garlic could enhance its antioxidant capacity, but could decrease its anti‐allergic activity. 相似文献
95.
96.
Andrew Wallace 《国际生产研究杂志》2013,51(4):709-726
Automated Guided Vehicle (AGV) systems are complex to design and to implement. Inefficiencies become difficult to avoid or even to control. This paper presents the theory behind a novel agent based AGV controller that aims to control the flow of AGVs in an effective manner and, therefore, overcome the inefficiencies that can be found in complex designs. Agents are simple entities that interact with other agents to produce an emergent behaviour that is not explicitly programmed into them. The AGV controller presented uses agents as traffic managers to allow access to points and segments in the guide path. Each agent has a rule base that it uses to assess the enquiries that it receives from an AGV. Each enquiry is evaluated only at the smallest possible part of the guide path rather than the entire guide path. AGVs are then able to allocate segments and points on their paths depending on the result of each enquiry. Simulation experiments were used to test the controller and an overview is presented. 相似文献
97.
Christopher Hahn Melissa A. Fardy Catherine Nguyen Michelle Natera-Comte Sean C. Andrews Peidong Yang 《Israel journal of chemistry》2012,52(11-12):1111-1117
Recently, (Ga1-xZnx)(N1-xOx) has gained widespread attention as a comparatively high efficiency photocatalyst for visible-light-driven overall water splitting. Despite significant gains in efficiency over the past several years, a majority of the photogenerated carriers recombine within bulk powders. To improve the photocatalytic activity, we used an epitaxial casting method to synthesize single-crystalline, high surface area (Ga1-xZnx)(N1-xOx) nanotubes with ZnO compositions up to x=0.10. Individual nanotubes showed improved homogeneity over powder samples due to a well defined epitaxial interface for ZnO diffusion into GaN. Absorption measurements showed that the ZnO incorporation shifts the absorption into the visible region with a tail out to 500 nm. Gas chromatography (GC) was used to compare the solar water splitting activity of (Ga1-xZnx)(N1-xOx) nanotubes (x=0.05–0.10) with similar composition powders. Cocatalyst decorated samples were dispersed in aqueous solutions of CH3OH and AgO2CCH3 to monitor the H+ reduction and H2O oxidation half reactions, respectively. The nanotubes were found to have approximately 1.5–2 times higher photocatalytic activity than similar composition powders for the rate limiting H+ reduction half reaction. These results demonstrate that improvements in homogeneity and surface area using the nanotube geometry can enhance the photocatalytic activity of GaN:ZnO for solar water splitting. 相似文献
98.
Vuchinich Rudy; Wallace Dennis; Milby Jesse B.; Schumacher Joseph E.; Mennemeyer Stephen; Kertesz Stefan 《Canadian Metallurgical Quarterly》2009,17(3):165
Clinical trials with cocaine-dependent outpatients have found a strong relation between in-treatment and follow-up abstinence, and the strength of this relation is constant across treatment conditions with variable efficacy in generating abstinence. The authors conducted secondary analyses of data from 3 clinical trials to determine whether this relation generalizes to cocaine-dependent homeless persons. The 3 trials (total N = 543) were conducted in a community health care facility for homeless people. The 7 treatment arms across the 3 trials were combinations of day treatment, abstinence-contingent housing, and vocational training. Drug use was measured with urine toxicology testing. Consecutive weeks of abstinence during treatment were strongly related to abstinence at the 12-month follow-up, whether or not missing 12-month data were included in the analysis. The treatment arms differed in their efficacy in generating abstinence, but the relation between in-treatment and follow-up abstinence did not differ across treatment arms. These results replicate earlier reports of these relations and extend them to a population of homeless people. The lack of differences between treatment arms in the in-treatment–follow-up abstinence relation implies that that relation is independent of the treatment-specific intervention components that generate group differences in abstinence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
100.
So‐called ‘dynamic'or ‘counterflow'insulation systems have already been installed in buildings in France and Sweden for which significant improvements over ‘classic’ insulation methods have been reported. Here, the authors describe a French study, including full‐scale laboratory tests, into the actual efficiency of a ‘permeodynamic’ version. A theoretical model has been developed from which to derive thermal efficiency values, and is compared with the test results. The limits of such dynamic systems, and their most feasible applications, are then discussed. The main conclusion is that conventional insulation techniques remain competitive for houses, but permeodynamic systems offer greater possibilities for industrial buildings. 相似文献