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971.
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973.
Given that banner ad investment is huge and keeps increasing, the effectiveness of banners is important for advertising practitioners and is worth attention from academics. Banner properties (e.g. format and animation) may influence the overall effectiveness of banners. However, research on how banner formats (e.g. location and orientation) affect banner effectiveness is still in its early stage and studies on how animation influences banner effectiveness have also found controversial results. By conducting an experiment using eye-tracking technology, this study investigated the impacts of banner properties, especially animation speed and format, on users' attention, recall, and attitudes towards banners. In terms of attention, both the main effects and the interaction effect were significant and the patterns varied across time. However, no significant effects were found on recall and attitudes. 相似文献
974.
Energy‐Efficient Train Speed Profile Generator Combining Partial Energy‐Oriented Driving Approaches
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One way of reducing the energy consumption of trains is to drive them in an energy‐efficient manner. There can be various driving patterns between two adjacent stops, or various speed profiles, because there is a gap called the running time supplement between the planned running time set in a timetable and the shortest possible running time of the train. Previous studies have proposed using up the supplement by changing the driving operation from powering to coasting at optimal points in terms of energy consumption. Others have shown that full use of regenerative braking helps save energy. In this study, we developed an energy‐efficient speed profile generator by combining these partial energy‐oriented driving approaches when the planned running time is given. We added this generator to existing shortest running time calculation software, so that it works for various vehicle and train route data. Numerical experiments showed that our profile provided superior performance compared to manually created ones for artificial and real data. 相似文献
975.
结合莱钢焦化厂4#干熄焦的现场实际,介绍了4#干熄焦提升机控制系统的构成、主要功能、提升和走行速度曲线,重点对提升机控制系统的PLC构成和控制做了介绍,整套系统自动化程度高,控制稳定、可靠。从目前的生产情况看,4#干熄焦提升机控制系统的设计完全满足干熄焦系统工艺安全、自动、高效的设计要求。 相似文献
976.
A new wind turbine emulator (WTE) is presented, which is able to simulate the turbine power curves without using a closed loop control system. The state of the art emulators use DC or AC motors, closed loop controlled by processors with the turbine power curves recorded. The presented emulator has a DC voltage source, a power resistor and a DC motor with independent excitation. The motor power curve has a shape similar to a wind turbine power curve for a given wind speed; the wind speed variations can be emulated by the variations of the DC voltage source. The open loop emulator is completely different and new, because it works in open loop and does not require the presence of a processor.The following elements are included: the theoretical foundations of the emulator, the emulator power curves adjustment procedure to simulate a commercial wind turbine and the experimental tests. 相似文献
977.
本文对高转速水轮发电机组的动平衡试验进行了研究,提出了一种比较实用的动平衡试验方法,这种方法具有仪器设备简便,启动机组次数少,平衡精度高等优点。 相似文献
978.
979.
北满基地北兴公司80t转炉煤气回收及一次除尘采用PLC控制技术,实现了风机系统与PLC的信号交换,从而实现风机自动调速、煤气回收、CRT集中监控等功能。系统自运行以来,性能稳定,满足了工艺设备的要求,煤气回收更加安全有效。 相似文献
980.
Chi Zhang Zhenyu LiuYang Xu Guodong Wang 《Journal of Materials Processing Technology》2012,212(11):2183-2192
During hot rolling of ferritic stainless steels (FSSs), sticking can cause severe surface defects both on work rolls and strips especially for ultra purified FSSs with the total amount of carbon and nitrogen being less than 150 ppm. In the present paper, high temperature oxidization behavior of the ultra purified FSSs was characterized. A new experimental method was invented to simulate the sticking behavior of ultra purified 21%Cr FSS, by which specially designed specimens were hot compressed with different processing parameters to simulate hot strip rolling process. The specimens were surface conditioned prior to the simulation test, either by mechanically polishing or by pre-oxidization to form oxide scales with certain thickness. Observation on the cross-section of sticky regions indicated that cracks had been formed by cyclic heating and cooling during hot deformation had been acting as nucleation sites for sticking particles. The results indicated that oxide scale could avoid the direct contact between roll surfaces and rolled materials to help reducing the sticking occurrence. The temperature region for easy sticking occurrence in the ultra purified 21%Cr FSS has been measured to be from 900 to 1100 °C, which is enlarged as compared to other plain FSSs. The tendency for sticking occurrence decreased with increasing strain rate and decreasing the hammer or work roll surface roughness. 相似文献