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51.
The main objective of this research was to evaluate two possibilities of material feed rate measurement of modern mowing machines equipped with conditioner. The machines are commonly used for harvest of grasses (Lolium multiflorum, Dactylus glomerata, Phleum pratense, etc.), clover (Trifolium pratense, etc.), alfalfa (Medicago sativa) etc.A mowing machine with finger conditioner was equipped with an electronic measuring unit for the purpose of our measurements. The mowing machine's conditioner shaft was supplied with strain gauges placed on a torque-meter and with a RPM optical sensor counter. Together with torque-meter the mowing machine was equipped with a curved impact plate mounted on the machine's material output.It was decided to arrange a laboratory measurement to obtain information about the dependence of conditioner power input and signals from the impact plate on material mass flow. A mixture of grass and alfalfa was used for our measurement.The measurements carried out proved that a very good linear relationship existed between the conditioner's power input, output frequency of the apparatus measuring impact force by means of the impact plate, and material feed rate through the mowing machine. The calculated coefficients of correlation were about 0.95. It is possible to differentiate a material feed rate difference of 0.5kgs–1 using both methods. This accuracy should be sufficient for practical utilisation such as creating yield maps. 相似文献
52.
原油罐金属底板的腐蚀与防护 总被引:1,自引:0,他引:1
针对原油罐区的腐蚀现状,分析了原油罐底板的腐蚀机理,通过对原油一罐的腐蚀调查、底板测厚,以及对罐底脱水中腐蚀介质及沉积物样的化学分析,提出了使用WF-50防腐涂料加阴极保护的方案,该方案可有效地防止原油罐金属底板的腐蚀。 相似文献
53.
54.
周绪红 《湖南农业大学学报(自然科学版)》1995,22(6)
采用半能量法对几种典型的卷边板件进行了弹性屈曲分析得到的解签揭示了卷边板件的三种新颖性屈曲模态和屈曲特征。 相似文献
55.
首先构造了一个完备的试函数,然后采用最小二乘配点法获得了不对称集中荷载作用下悬臂三角形板弯曲问题的解。 相似文献
56.
本文描述了落叶松脲醛树脂胶合板的开发试验,试验结果表明,落叶松胶合板比椴木胶合板,桦木胶合板,水曲柳胶合板和杨木胶合板的耐老化性能和耐水性能强,并且强度较高。 相似文献
57.
利用聚丙烯酰胺垂直板凝胶电泳技术对南农选系及16 个当前生产上应用较多的草地早熟禾品种的过氧化物酶同工酶进行了研究。结果表明,供试材料共在18 个位点表现酶带。南农选系表现出13条酶带,除与其它16个品种所共有的6 条主酶带外,还出现了其特有的7 条酶带。对不同品种POD同工酶酶谱信息进行相异性类平均聚类分析,17 个供试品种(系)聚为3 类,其中南农选系、美国品种“Merit”及其它15个品种分别各成一类。据此推测,南农选系与其它供试品种的亲缘关系相对较远,为一个相对独立的品系。 相似文献
58.
In this paper, based on Guyon''s and Massonnet''s method, the multi-span continuous curved girder bridge with the variable cross section is simulated as a thick-varied transversal|y sector plate. And then by means of the flexibility method, the middle suppo 相似文献
59.
美国NUCOR钢厂热轧板卷首次在国内卷管中应用,为了获得第一手资料,对其首批进口的板卷抽样进行了化学成分分析、力学性能试验和卷管后的爆破试验,分析结果表明,该厂生产的X65热轧板卷(首批进口)的各项性能均符合API标准规定和意大利斯南普吉提公司的设计要求。卷管将使用于库鄯输油管道。 相似文献
60.
van Klaveren NJ Suwankong N De Boer S van den Brom WE Voorhout G Hazewinkel HA Meij BP 《Veterinary surgery : VS》2005,34(5):450-456
OBJECTIVE: Using force plate analysis (FPA), determine ground reaction forces in dogs with degenerative lumbosacral stenosis (DLS) and evaluate the effects of lumbosacral decompressive surgery. STUDY DESIGN: Prospective clinical study. ANIMALS: Twelve dogs with DLS. METHODS: DLS was diagnosed by clinical signs, radiography, computed tomography, and/or magnetic resonance imaging. FPA was performed before surgery, and 3 days, 6 weeks, and 6 months after surgery. The mean peak braking (Fy+), peak propulsive (Fy-), and peak vertical (Fz+) forces of 8 consecutive strides were determined. The ratio between the total Fy- of the pelvic limbs and the total Fy- of the thoracic limbs (P/TFy-), reflecting the distribution of Fy-, was analyzed to evaluate any changes in locomotion pattern postoperatively. Ground reaction force data for DLS dogs were compared with data derived from 24 healthy dogs (control). RESULTS: In dogs with DLS, the propulsive forces (Fy-) of the pelvic limbs were significantly smaller than those of controls. P/TFy- was significantly smaller in dogs with DLS than in control dogs, and increased during the follow-up period, reaching normal values 6 months after surgery. CONCLUSIONS: Cauda equina compression in dogs with DLS decreases the propulsive force of the pelvic limbs and surgical treatment restores the propulsive force of the pelvic limbs in a 6-month period. CLINICAL RELEVANCE: In dogs with DLS, FPA is an effective method in evaluating the response to surgical treatment. Normal propulsive force in the pelvic limbs was restored during 6 months after decompressive surgery. 相似文献