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71.
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A paraffin wax formulation releasing pheromone for mating disruption of insects was tested during 2005 and 2006 in Vitis labrusca vineyards infested by grape berry moth, Paralobesia viteana (Lepidoptera: Tortricidae). In early May of each year, 1-ml droplets of SPLAT-GBM wax containing 3% sex pheromone of P. viteana were applied to every wooden post at a rate of 400/ha in replicated 1.3-ha plots. Moth captures in sex pheromone baited traps placed at the vineyard borders and interiors revealed significant disruption of male moth captures in treated plots, with activity of one application lasting over 10 weeks during both years. Treatment with SPLAT-GBM did not affect the proportion of clusters infested until the end of the second growing season, when infestation was 27% lower in the treated plots than in the control plots. Comparisons of moth captures in traps placed inside 15.2 x 16.5 m vine plots that were untreated or received varying densities of 0.2-ml wax drops or Isomate-GBM hand-tied dispensers at the recommended rate of 450/ha indicated that orientational disruption increased with droplet density. Similar numbers of moths were captured in plots that received 10 or 30 drops per vine as were trapped in plots with twist ties spaced at 0.4 per vine. Moth captures in monitoring traps baited with increasing sizes of wax droplets (0.2, 0.5, or 1-ml drops) or red septa containing P. viteana sex pheromone suggest decreasing ability of male moths to reach traps with increasing pheromone loading. This study indicates that wax-deployed pheromone can reduce crop infestation by P. viteana after 2 years of deployment, and that the increasing of pheromone release by using application of greater droplet densities or by using larger droplets will improve the level of disruption achieved. 相似文献
73.
简述了交流调速理论和电子电力器件的发展,利用TMS3202407 DSP以及第四代电子电力元件IPM,实现了矢量控制变频算法,提出了一种高性能通用变频器的设计方法。 相似文献
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75.
介绍了采用TI公司32位工业控制专用数字信号处理器TMS320F2812作主控制器的电力机车用直流110V高频大功率开关电源全数字化系统设计方案,详细描述了系统的硬件结构与软件控制算法。实验与样机装车实际考核证明,该方案技术先进,性能优良,值得继续深入研究与推广。 相似文献
76.
This paper presents new path planning algorithms for bipedal robots without a trunk. The proposed methods can be regarded as an extension to the concept of the inverted pendulum mode (IPM). Further, they fill the gap between the IPM and concepts, based on general dynamic modeling. The swing leg motion is adjusted almost arbitrarily and the torso motion is calculated analytically in order to ensure stability. The proposed methods show a higher gait stability compared to literature approaches. This improvement is verified by measurement of the foot reaction forces during the walk of the existing biped BARt-UH and simulations. 相似文献
77.
介绍了用于马达控制的电力变换器和电力半导体开关变换元件 ,包括各种电力变换器型式及方式、新型电力半导体元件 IGBT和 DUGMOT。 相似文献
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79.
据估计,电动机消耗了中国一半以上的电能,传统的机械式控制方法用电效率不到50%,而基于逆变器的变速驱动设计可以节约大部分被浪费掉的电能。要提高基于逆变器的调速驱动器的使用牢,必须找到一种可以简化结构同时保持高效性能的设计方法。新型iMOTION^TM芯片组包括一个特殊的运动控制引擎(MCE,Motion Control Engine)和一个永磁电动机驱动专用的高压集成电路(IC)。本文介绍了该芯片组在空调设计中的应用,并给出了相关的测试数据。 相似文献
80.
Hiroyasu Hagino Tomihisa Yamada Akio Uenishi Yoshifumi Tomomatsu 《Electrical Engineering in Japan》1995,115(8):95-108
It is important to remove the transitional peak current in sense-emitter current which is due to dynamic current-sharing during turn-on for a design of IGBTs with current-sense used protection against overcurrent and short circuit. But this analysis has been scarcely investigated. This paper clarifies generation mechanisms of the transitional peak current by simulations and experiments using a parallel operation model and reports on techniques to remove it. The following results were obtained. (1) In the two paralleling devices model which consists of a sense cell and main cells, the transitional peak current occurs during turn-on when a sense cell turns on faster than main cells. In this case, the main parameters that effect dynamic currents imbalance are gate resistance (Rg) and gate threshold voltage (Vth). (2) In dynamic currents imbalance based on individual Rg and Vth among main cells, it may be treated as a two-paralleling devices model which consists of a sense cell with Rgs and Vths, and main cells with average values Rgm and Vthm. (3) The transitional peak current can be removed by the design of Rgs and Vths in a sense cell are larger than average values of Rgm and Vthm in main cells. (4) On trial IGBTs with current sense Vths in a sense cell is different from the average-value Vthm in main cells to change impurity concentrations of each channel. It was confirmed that the transitional peak current in sense-emitter current can be removed by the design that Vths in a sense cell is larger than average value Vthm in main cells. 相似文献