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981.
桉树营养状况与叶片营养诊断研究 总被引:24,自引:2,他引:24
本文研究了雷林1号桉、尾叶桉和柠檬桉一年和三年生植株养分浓度及养分积累量;叶片营养诊断的采样时间、诊断方法,并用临界值法和系统综合诊断法诊断桉树施肥“中试”区的营养状况。 相似文献
982.
人工神经网络技术在变速箱故障诊断中的应用 总被引:1,自引:0,他引:1
阐述了人工神经网络技术在变速箱故障诊断中的一般方法,重点介绍了人工神经网络模型训练参参数数的选择和机械故障信息的提取方法,实验结果表明,人工神经网络技术可以快速、准确地诊断出机械故障类型。 相似文献
983.
984.
Containerized red pine (Pinus resinosa Ait.) seedlings were grown over a 16-week rotation at different irrigation treatments to assess moisture stress on plant growth and nutrition, and to evaluate container capacity as a guide for irrigation. Wet, moist and dry moisture regimes were induced by watering trees to the container capacity weight of the growing medium after declining to respective 92, 73 and 57% of this reference weight. The seedlings received the same amount of fertilizer over the growth period. Maximum shoot and root growth was attained under the wet moisture regime, but biomass was reduced 21 and 43% for the moist and dry regimes. Plant nutrient concentrations were not significantly affected by watering treatment, and vector diagnosis of dry matter production and element composition indicated that macronutrients were non-limiting. Seedling nutrient uptake however, was significantly diminished by moisture stress which was attributed to decreased root growth and lower mass flow and diffusion of nutrients when moisture availability was reduced in the peat rooting media. Container capacity was found to be a sensitive reference for judging the watering requirements of greenhouse-grown containerized seedlings. The method can be relatively easily applied on an operational basis. 相似文献
985.
INTRODUCTIONAccordingtOstatlshcs,w1enanewtrtlckhastraveledoverlOo,OOOkn1,tl1egear-sluftlllechanisl11ingearboxisoftel1outoforder,andaftertWohundredandtwenty-fivekilo11le-ters,thehalfofthepartsinthetrans111issionsyst6mareall11ostchanged.Tl1etrUckofte11travelsontheabnon11alcondihon.ForlogProduchon'tllelognl1gtrtlckge11erallytravelsinmaintainousareaandtl1etfansPOrtanontasksaremalnlydoneinwinter.IfaloapngtrUckisoutoforderinmohon,thetransPOrta-honisdifficultytobecol11pleteda11dtl1edriver'S… 相似文献
986.
987.
Erosion Optimized Diagnosis of Brand Grounding Grid 总被引:1,自引:0,他引:1
To find the corrosion of the grid ,large area cutting has been adopting in practice for a very long time. But this method is blind, difficult and influences the system operating. The erosion diagnosis method in the past is effective for the smaller grid. To the brand ones, it can not take effect. The method of separating the grounding grid into several parts and diagnosing step by step is discussed by lots of simulation about middle or brand grounding grid erosion diagnosis. This method makes the brand grounding grid erosion diagnosis quick and truly without power cut and digging large area, satisfies the demand in practice. Putting this optimized diagnosis method into practice , the result is good. 相似文献
988.
989.
This paper presents a modulation phenomenon of complex vibration which occured when gear teeth broke or shaft seriously bent in gearbox. Based on the mechanism of gear vibration and modulation sideband,the peper analyzes this complex modulation phenomenon. 相似文献
990.
The governing system of hydraulic turbine generator plays an important role in power system. It is significant to find out the faults of governing system and remove them quickly. This paper sets up a new fault diagnosis model of the hydraulic turbine generator governing system with the advanced ANN (artificial neural net). This 17-in-13-out model consists of three layers. It is proved that this model can find the fault accurately. 相似文献