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In this paper, the design of a computer-based training (CBT) system for low-functioning autistic children is addressed. The emphasis is on ease-of-use and learning efficiency of CBT systems with different interaction styles, namely the WIMP (Window Icon Menu Pointing Device) and TUI (Tangible User Interface) interaction styles. Two WIMP-based CBT systems with different pointing devices were involved in the study. The first system applied a standard computer mouse as a pointing device, while the second one employed a touch screen instead. For the TUI-based CBT system, a tabletop setting was adopted. Based on the known characteristics of TUI and children with autism, as well as related cognitive and learning theories, the benefits of TUI for low-functioning autistic children have been investigated. Elementary skill teaching was chosen as a case study for performance evaluation of these CBT systems. Empirical results show that the touch-based and TUI-based systems offered much better ease-of-use performance than that of the mouse-based system. Regarding learning efficacy, experimental results show that the TUI-based system achieved higher skill improvement, as compared with the WIMP-based system and a non-computer training method. Some guidelines and suggestions for the design of a TUI-based system for children with autism are summarized.  相似文献   
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ICP-AES法测定废水中七种元素   总被引:3,自引:0,他引:3  
叶林 《铜业工程》2004,(2):54-56
取废水 5 0ml,加入 1mlHNO3 ,在电炉上消化之后 ,过滤进 5 0ml比色管中 ,直接用ICP -AES法对Cu、Pb、Fe、Mn、As、Be等元素进行定量分析  相似文献   
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Hierarchical carbon scaffold (HCS) with multi-porous structures, favoring hydrogen diffusion and physisorption is doped with 2–10 wt % Ni for storing hydrogen at ambient temperature. Due to N- and O-rich structure of melamine-formaldehyde resin used as carbon precursor, homogeneous distribution of heteroatoms (N and O) in HCS is achieved. 2 wt % Ni-doped HCS shows the highest hydrogen capacity up to 2.40 wt % H2 (T = 298 K and p (H2) = 100 bar) as well as excellent reversibility of 18.25 g H2/L and 1.25 wt % H2 (T = 298 K and p (H2) = 50 bar) and electrical production from PEMFC stack up to 0.7 Wh upon eight cycles. Computations and experiments confirm strong interactions between Ni and heteroatoms, leading to uniform distribution small particles of Ni. This results in enhancing reactive surface area for hydrogen adsorption and preventing agglomeration of Ni nanoparticles upon cycling. Ni K-edge XANES spectra simulated from the optimized structure of Ni-doped N/O-rich carbon using DFT calculations are consistent with the experimental spectra and suggest electron transfer from Ni to hydrogen to form Ni–H bond upon adsorption. Considering low desorption temperature (323 K), not only chemisorbed hydrogen is involved in adsorption mechanisms but also physisorption and spillover of hydrogen.  相似文献   
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Biofilms are complex bacterial communities have a mechanism for antibiotic resistance leading to human health problems. It remains challenging to treat and eradicate biofilms. In this work, the use of d-maltose synthesized silver nanoparticles (AgNPs) was investigated in an effort to eradicate a biofilm. AgNPs were synthesized using a modified Tollen’s method. d-maltose was used in synthesizing AgNPs with different concentrations of d-maltose (0.01, 0.05 and 0.1 M), referred to as NP1, NP2 and NP3, respectively. TEM images revealed that the particles were polygon shaped. The particle sizes were found to be 86.81?±?13.39, 54.94?±?11.63 and 31.43?±?31.76 nm depending on their sugar concentrations. UV–Vis, ATR–FTIR, and XRD patterns were employed to characterize the AgNPs. Then, these AgNPs were investigated for their anti-bacterial effects against Escherichia coli and Staphylococcus aureus. Evaluation of the minimum inhibitory concentration and minimal bactericidal concentration revealed that S. aureus was inhibited by all AgNPs and killed by NP1 and NP3, and E. coli was inhibited and killed at all AgNPs doses. Furthermore, anti-biofilm activity against these two bacteria was observed using SEM and confocal laser scanning microscopy. This sugar coated AgNPs is a promising material for use in eradication of biofilms.  相似文献   
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The goal of this study was to sequential fermentation of hydrogen and methane from sugarcane bagasse (SCB). Steam explosion conditions for pretreating SCB were optimum at 195 °C and 1.5 min, which yielded 36.35 g/L of total sugar and 2.35 g/L of total inhibitors. Under these conditions (all in g/L): glucose, 11.33; xylose, 24.41; arabinose, 0.61; acetic acid, 2.33; and furfural, 0.02 were obtained. The resulting hydrolysate was used to produce hydrogen by anaerobic mixed cultures. A maximum hydrogen production rate of 396.50 mL H2/L day was achieved at an initial pH of 6 and an initial total sugar concentration of 10 g/L. The effluent from the hydrogen fermentation process was further used to produce methane. Response surface methodology with central composite design was used to obtain the suitable conditions for maximizing methane production rate (MPR). An MPR of 185.73 mL/L day was achieved at initial pH, Ni and Fe concentrations of 7.59, 3.61 mg/L and 8.44 mg/L, respectively. Total energy of 304.11 kJ/L-substrate was obtained from a sequential fermentation of hydrogen and methane. This approach will not only add value to SCB, in the form of safe and clean energy, but also provide a solution for making use of this abundant waste.  相似文献   
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Reduced graphene oxide (rGO) nanosheets were produced using a modified Hummers method. Antifungal activity of rGO nanosheets was tested against three fungi i.e., Aspergillus niger (A. niger), Aspergillus oryzae (A. oryzae) and Fusarium oxysporum (F. oxysporum). The rGO inhibits the mycelial growth of the fungi and it is believed that this is due to its sharp edges. The half maximal inhibitory concentration (IC50), a measure of the effectiveness of the rGO in inhibiting the fungi, was investigated. IC50 values of the rGO against F. oxysporum, A. niger, and A. oryzae are 50, 100, and 100 μg ml?1, respectively.  相似文献   
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The authors in this study examined the function and public reception of critical tweeting in online campaigns of four nationalist populist politicians during major national election campaigns. Using a mix of qualitative coding and case study inductive methods, we analyzed the tweets of Narendra Modi, Nigel Farage, Donald Trump, and Geert Wilders before the 2014 Indian general elections, the 2016 UK Brexit referendum, the 2016 US presidential election, and the 2017 Dutch general election, respectively. Our data show that Trump is a consistent outlier in terms of using critical language on Twitter when compared to Wilders, Farage, and Modi, but that all four leaders show significant investment in various forms of antagonistic messaging including personal insults, sarcasm, and labeling, and that these are rewarded online by higher retweet rates. Building on the work of Murray Edelman and his notion of a political spectacle, we examined Twitter as a performative space for critical rhetoric within the frame of nationalist politics. We found that cultural and political differences among the four settings also impact how each politician employs these tactics. Our work proposes that studies of social media spaces need to bring normative questions into traditional notions of collaboration. As we show here, political actors may benefit from in-group coalescence around antagonistic messaging, which while serving as a call to arms for online collaboration for those ideologically aligned, may on a societal level lead to greater polarization.  相似文献   
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