PEPT study of particle cycle and residence time distributions in a Wurster fluid bed

Particle cycle and residence time distributions are critical factors in determining the coating quality in the Wurster process. Positron emission particle tracking experiments are performed to determine the cycle and residence times of particles in different regions of a Wurster fluid bed. The results show that particles tend to recirculate in and sneak out below from the Wurster tube. The experiments also show that a larger batch size leads to a shorter cycle time and a narrower cycle time distribution (CTD). It is possible to avoid recirculations and obtain a shorter cycle time and a narrower CTD by selecting the operating conditions appropriately or via equipment design. Experiments using binary mixtures of particles with a diameter ratio of 1.5 show that large particles have a longer cycle time than small particles and that the cycle time is shorter for mixtures with approximately equal amounts of small and large particles. © 2014 American Institute of Chemical Engineers AIChE J, 61: 756–768, 2015     

形变量对冷轧高纯镍高温退火行为的影响

应用电子背散射衍射分析(EBSP)对形变量分别为90%、96%和98%的冷轧高纯镍在高温下完全再结晶退火后的微观组织和织构进行分析.结果表明,立方织构随着退火温度和形变量的增大而升高,98%形变量的镍试样在高温退火后可以得到集中的立方织构和较小的晶粒尺寸,是超导覆膜基带的较好选择.     

Oxidation with air of cyclohexanone to carboxylic diacids on carbon catalysts

Carbons derived from phenolic resins were used as catalysts for the aqueous phase oxidation of cyclohexanone at 140°C under air pressure. The reaction yielded mainly adipic, glutaric and succinic acids. The samples were modified by heat treatments in CO₂, air or N₂ at different temperatures and characterized to determine their surface area and porosity and to evaluate the functional groups on the surface. Treatments under CO₂ or air increased the oxidation activity. The selectivity to adipic acid was maximum (33%) after activation in air which greatly increased the surface concentration of oxygen-containing functional groups. However, it was not possible to attribute the selectivity to specific acidic, neutral or basic groups present at the surface of carbons. This revised version was published online in June 2006 with corrections to the Cover Date.     

智能屏幕在工业控制中的应用

智能屏幕人机界面的开发人员通过使用闪存和C／C＋＋组件，使产品达到了工业级的可靠性和实时性能。楼宇自动化系统的设计便是一个例子。     

Software Assumptions Lead to Preventable Errors

Undocumented assumptions are often the cause of serious software system failure. Thus, to reduce such failures, developers must become better at discovering and documenting their assumptions. In this article, we focus on common categories of assumptions in software, discuss methods for recognizing when developers are making them, and recommend techniques for documenting them.     

High performance GaAs MESFETs with molecular implanted and optimized lowly-doped drain structure for maximized speed, gain and breakdown performance

GaAs MESFETs with novel lowly-doped drain structures have been developed utilizing molecular implants of silicon trifluoride. Short-channel effects in the 1/4 μm enhancement- and depletion-mode transistors have been suppressed with drain-induced barrier height lowering of less than 70 mV/V and pinch-off voltage shifts of less than 220 mV as the gate length was scaled from 1.0 to 1/4 μm. The 3-terminal breakdown, the transconductance to output conductance ratio, and the unity current gain, cut-off frequency were simultaneously optimized. The E-mode device possessed breakdown of >10 V, G_m · R_ds > 9.5, F_t > 55 GHz, and nominal on-resistance of 2.1 Ω mm while the D-mode device had breakdown >10 V, G_m · R_ds > 6.0, F_t > 45 GHz, and nominal on-resistance of 1.9 Ω mm. These optimized transistors enabled the realization of a variety of low-power digital and high-power mixed signal circuits, using 3-level source-coupled transistor and common-mode logic, such as laser and electro-optic drivers, highly integrated transceivers, multiplexers, demultiplexers, and clock data recover circuits.     

Self‐help housing provision: Production,consumption, accumulation and policy in Atlantic Canada

Self‐help has been a neglected aspect of housing provision in industrialised nations, yet in many locations it accounts for a significant share of new production and can contribute to improved housing circumstances for those whose housing need is not too severe. This paper discusses self‐help housing provision in Atlantic Canada and argues that it reduces the profitability of the residential construction industry and for this and other reasons, self‐help is likely to continue as a major form of production. This paper also evaluates the impact on self‐help of several housing policy options.     

Metric and reference factors in minimum error rate training

In Minimum Error Rate Training (MERT), Bleu is often used as the error function, despite the fact that it has been shown to have a lower correlation with human judgment than other metrics such as Meteor and Ter. In this paper, we present empirical results in which parameters tuned on Bleu may lead to sub-optimal Bleu scores under certain data conditions. Such scores can be improved significantly by tuning on an entirely different metric altogether, e.g. Meteor, by 0.0082 Bleu or 3.38% relative improvement on the WMT08 English–French data. We analyze the influence of the number of references and choice of metrics on the result of MERT and experiment on different data sets. We show the problems of tuning on a metric that is not designed for the single reference scenario and point out some possible solutions.     

成功的因素与失败的教训

Andy：大家好，我是Andy Plata。 Julie：我是Julie Plata。很高兴今天能在这里为大家演讲。我和Andy共同拥有一些服务于全球印刷业的公司。我们也为全球许多印刷类刊物撰文，我想诸位应该已经读过我们在科印传媒《数码印刷》杂志上发表的文章。