Exploiting ambient illumination to locate and recognise user behaviour in enclosed environments

Experiences in pervasive computing environments often rely on estimates of the location and/or behaviour of participants to tailor interaction and/or content to the particular user context. In this paper, we present a novel computer vision method for the indirect monitoring of user position and behaviour. The technique classifies activities based on measurements of the disruptions those activities cause in the surrounding ambient light field. The potential advantages of the method are increased privacy, an ability to recognise high level behaviours and events, and applicability in dimly lit environments. Initial experiments show the technique to be capable of recognising user position within an enclosed environment with at least 75% accuracy. A study of time-based events further shows it to be capable of discriminating between different paths taken through an enclosed space by different sized groups of users with 84% accuracy. We conclude by discussing possible applications of the technique in pervasive computing environments.     

天龙AVR—1802AV放大器

不知道大家是否领略过天龙旗舰影音放大器AVC-AlSE的迷人风采,多得让人眼花缭乱的功能设置,无坚不摧的强大功率输出,精益求精货真价实的制造工艺,这都无疑会引起发烧友的强烈关注.只是2万多的售价只会使这部参考级AV放大器叫好不叫座,价廉物美的走超值路线的机种才能成为市场的宠儿,才能成为具有竞争力的"战斗机".AVR-1802正是这样的产品.     

Poly(lactic acid) membranes containing bacteriocins and EDTA for inhibition of the surface growth of gram‐negative bacteria

Films containing antibacterial reagents, ethylenediamine‐tetraacetic acid disodium salt (EDTA) and Nisaplin^®, were produced by coextrusion with poly(lactic acid) in the presence of a pharmaceutical grade glycerol triacetate. The incorporation of EDTA‐Nisaplin^® particles resulted in a heterogeneous biphasic structure, as revealed by scanning electronic microscopy, confocal laser microscopy, and acoustic emission tests. The inclusion of glycerol triacetate reduced the Young's modulus and tensile strength, while enhancing the flexibility and the toughness of the resulting blends. The inclusion of the plasticizer also allowed the extrusion to occur at a temperature as low as 120°C to maintain the biological activity of Nisaplin^®, which in combination with EDTA, plays a synergistic effect on suppression of the growth of the Gram‐negative bacteria, E. coli O157:H7. The films thus obtained show potential as packaging materials with a wide spectrum of antimicrobial activity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Comparison of Activated Carbon and Hydrophobic Zeolite Efficiencies in 2,4-Dichlorophenol Advanced Ozonation

This study aims at comparing the removal of 2,4-dichlorophenol (2,4-DCP) by 3 methods; adsorption using hydrophobic zeolite (faujasite) or activated carbon (S-23 and L-27), conventional ozonation and hybrid adsorption/ozonation treatment. On the one hand, the three materials correctly adsorb 2,4-DCP; however the adsorption kinetics using zeolite is very low. On the other hand, ozonation totally removes 2,4-DCP after 1 h experiment and the simultaneous combination of adsorbent and ozone does not change the 2,4-DCP degradation. But, though ozonation and hybrid process appear to be equivalent for 2,4-DCP removal, activated carbons are able to decompose ozone and to improve chemical oxygen demand (COD) removal, whereas the zeolite does not show this catalytic effect. Similar results were also observed in a former study with nitrobenzene. Adsorbent degradation is evaluated by Brunauer, Emmet and Teller (BET) and differential thermogravimetric (DTG) analysis, which evidence that Faujasite and S-23 activated carbon are resistant to ozone exposure whereas the pore volume and the surface area of L-27 activated carbon decrease during ozonation.     

Problems Associated With Spray Drying Of Sugar-Rich Foods

ABSTRACT

Stickiness is a major reason that limits the spray drying of various sugar-rich food products.Higher hygrmopicity of amorphous powder, increase in solubility of sugars with temperature, and lower melting point and glass transition temperature, contribute to the aickiness problem. So far, the glass transition temperature has been widely accepted as a ben indicator for stickiness. There are various manawm that have been applied to spray dry such product. Some of them are the addition of drying aids, modilication of drier design and use of mild drying temperature conditions. This review paper highlights the major research works that deal with the stickiness property of sugar-rich foods.     

半导体激光器在塑料焊接中的应用

在形形色色的塑料加工工具中，ＣＯ２激光器在近些年被证实是塑料切割、钻孔以及雕刻的理想工具。激光技术的最新发展更引发了人们对使用高功率半导体激光器进行塑料焊接的兴趣。 半导体激光器在输出功率、转换效率、可靠性以及耗费等方面持续地改进和提高，是引发人们对使用高功率半导体激光器进行工业加工产生兴趣的原因，因为上述这些品质都是适合工业应用必不可少的关键品质。半导体激光器的体积紧凑是相比其他成熟激光器的另一个重要的优点，尤其适合于自动化生产和使用机器人的环境。小巧而耗电省的激光器可以被直接固定在机械手上，…