基于有限元的连杆优化设计   总被引：7，自引：1，他引：7  

张继春  李兴虎  孙刚 《拖拉机与农用运输车》2006,33(1):27-30,33

首先对连杆进行有限元分析,确定了连杆的应力集中点和最大变形量,然后对连杆的应力点及其相关尺寸参数进行灵敏度分析,找出对其影响最大的尺寸参数。利用优化设计和有限元计算相结合的技术,以连杆质量最小作为目标函数对连杆进行优化设计。  相似文献   

Neural network prediction of performance parameters of an inclined plate seed metering device and its reverse mapping for the determination of optimum design and operational parameters   总被引：2，自引：0，他引：2  

M. Anantachar  T. Guruswamy 《Computers and Electronics in Agriculture》2010,72(2):87-98

Seed planting equipment with inclined plate seed metering devices is the most commonly used equipment for planting of peanut crop in India. For obtaining the high yield, it is very essential to drop the peanut seeds in rows maintaining accurate seed rate and seed spacing with minimum damage to seeds during metering. This mainly depends on forward speed of the planting equipment, rotary speed of the metering plate and area of cells on the plate. The relationship between these factors and the performance parameters viz., seed rate, seed spacing and percent seed damage can be established using regression analysis. But they may not be very accurate and may pose difficulty in the determination of inputs for a set of desired outputs (reverse mapping). Hence, an attempt has been made in this paper to develop the feed forward artificial neural network (ANN) models for the prediction of the performance parameters of an inclined plate seed metering device. The data were generated in the laboratory by conducting experiments on a sticky belt test stand provided with a seed metering device and an opto-electronic seed counter. The generated data was used to develop both statistical and neural network models. The performance of the developed models was compared among themselves for 4 randomly generated test cases. The results show that the ANN model predicted the performance parameters of the seed metering device better than the statistical models. In order to determine the optimum forward speed of the planting equipment, peripheral speed of the metering plate and the area of cells on the plate to obtain the recommended seed rate of 33.33 seeds/m², seed spacing of 100 mm and percent seed damage of 0.2% with 100% fill of the cells, a novel technique of reverse mapping using ANN model was followed. It was observed that the optimum forward speed of the planting equipment and optimum area of cells on the metering plate had good correlation with size of seed. Linear regression equations were developed to predict the optimum forward speed of the planting equipment and optimum area of cells on the metering plate using the size of seeds as independent parameter. The peripheral speed of the metering plate of 0.237 m/s was found to be optimum for the size of seeds in the range of 95.42-123.01 mm². However, the results need to be verified by conducting planting operation under actual field conditions.  相似文献   

安徽农村信息环境优化对策研究——基于对安徽省部分农村的调研   总被引：1，自引：0，他引：1  

郑家欢  吴志祥 《安徽农学通报》2011,17(17):152-153,177

农村信息的开发利用在新农村建设过程中起着至关重要的作用。而农村信息资源开发的程度又往往局限于信息环境,优化农村信息环境对于提高农村信息化程度日趋重要。通过对安徽省部分农村的调研,分析了安徽农村信息环境的现状,并针对存在的问题提出了优化对策与建议。  相似文献   

规范土地收储管理,优化土地资源配置——2005～2009年苍溪县城镇土地收储调查     

李锦德  侯甫礼 《农机具之友》2010,(11):36-36,42

在城市建设中,土地的收购、储备、出让行为,对城市建设和发展的影响非常直接,极其关键。因此,要规范土地收储管理,优化土地资源配置。  相似文献   

苇状羊茅与多年生黑麦草内生真菌菌丝基因组DNA提取的优化及PCR初步检测     

廖芳  刘跃庭  崔铁军  黄国明  罗家凤  尹旭芳 《植物检疫》2006,20(5):265-268

感染内生真菌的禾草在牧草和草坪业上具有重要的生态和经济意义，家畜采食感染Neotyphodium coenophialum和N.lolii的苇状羊茅和多年生黑麦草会发生中毒。本研究收集天津口岸1998年以来进境的部分苇状羊茅和多年生黑麦草种子，对经镜检确认带有内生真菌的种子进行分离培养，对疑似菌株的菌丝用改进的Moiler等方法进行基因组DNA抽提，测定浓度及纯度，对照原方法，DNA的纯度有较大提高，浓度略有上升。Tubulin2基因的引物IS1-IS3扩增结果显示为单一的条带，结合形态学和序列比对，分离培养得到的菌株可以基本确定为N．coenophialum和N。lolii。根据Genbank中N.coenophialum和N.lolii的NC25基因序列设计出引物F1-R1，扩增得到能区分开N.coenophialum和N．lolii的单一条带（相差160bp），建立了N．coenophialum和N．lolii的PCR检测方法，结果准确可靠。  相似文献   

灵芝多糖液体发酵条件优化   总被引：3，自引：0，他引：3  

王慧杰  李宇伟  连瑞丽  王志强  马爱民 《食用菌学报》2007,14(1):37-41

从一系列灵芝(Ganoderma sp.)菌种中筛选出多糖产量高、生长快的紫灵芝菌株(G.japoncium),研究了不同氮源、碳源及金属离子对紫灵芝产多糖的影响。结果表明,以2%的蔗糖为碳源,0.2%的豆饼粉为氮源,0.2%的FeSO4为培养基可获得较高多糖。发酵罐放大实验表明,采用同样的培养基,每100mL发酵液胞外粗多糖含量可高达181.7mg,每100mL发酵液菌丝体含量可高达151.0mg,发酵过程中pH值的变化比较缓和,相对摇瓶生长,发酵生产可获得更多的灵芝多糖。  相似文献   

用发酵罐制备嗜水气单胞菌疫苗用菌液培养条件的优化   总被引：5，自引：0，他引：5  

范红结  陈怀青  陆承平 《中国兽药杂志》1998,32(2):11-13

本试验探讨了用发酵罐培养嗜水气单胞菌灭活疫苗生产菌株Ｊ－１株菌液的最佳条件。分别以发酵罐和摇床在不同的培养条件下培养Ｊ－１株制备菌液,前者１２个批次,后者６个批次。比较不同的培养条件对细菌菌体数量及ＨＥＣ毒素产量的影响。结果表明：发酵罐培养优于摇床培养,以产毒素培养基于２８℃发酵罐通气培养Ｊ－１株,培养２８小时效果最佳,培养菌液含菌量达２．９×１０１０ｃｆｕ／ｍｌ,培养液上清的溶血价达２７,发酵液中残糖为０．１２ｇ／Ｌ,符合发酵工艺要求。  相似文献   

Bacillus subtilis SPB1 biosurfactant: Production optimization and insecticidal activity against the carob moth Ectomyelois ceratoniae     

《Crop Protection》2013

Bacillus subtilis SPB1 was shown to produce a lipopeptide biosurfactant. The insecticidal activity of this biosurfactant was evaluated against Ectomyelois ceratoniae Zeller, a moth pest of stored dates in Tunisia. The LC₅₀ and LC₉₀ values after six days of contact were 152 μg/g and 641 μg/g, respectively. To promote an economical production of this highly effective bioinsecticide, statistical experimental designs and response surface methodology were employed to optimize the concentrations of agro-industrial residues and humidity, for lipopeptide biosurfactant production by B. subtilis SPB1 under solid state fermentation. The optimal medium leading to a production yield near to 28 mg of crude lipopeptide preparation per g of wet solid material was composed of a mixture of 4.34 g of tuna fish flour and 5.66 g of potato waste flour with a moisture content of 76%.  相似文献   

石化污泥脱水工艺优化研究     

杨瑞洪  刘丹 《安徽农业科学》2010,38(30):17015-17016

[目的]确定污泥最佳絮凝剂种类及其最佳的投加量和脱水工艺参数。[方法]针对石化企业污泥脱水工艺中存在的问题，以污泥沉降性能、污泥比阻和滤饼含水率为指标筛选出最佳絮凝剂，并通过正交试验对污泥脱水工艺进行优化。[结果]各因素对滤饼含水率的影响顺序为：搅拌水平〉投加量〉抽滤压力〉絮凝剂。最佳操作条件为絮凝剂K6728投加量2．0ml；搅拌水平150r／min 10s，50r／min 10min：过滤压力0．05MPa。各因素对污泥比阻的影响顺序为：搅拌水平〉抽滤压力〉投加量〉絮凝剂。最佳操作条件为絮凝剂K6728投加量2．5ml；搅拌水平150r／min 10s，50r／min 10min；过滤压力0．03MPa。综合分析得出最佳工艺参数为：K6728絮凝剂投加量2．0ml；搅拌水平150r／min 10s，50r／min 10min；过滤压力0．03MPa。此时，污泥脱水效果最佳。[结论]优化了石化污泥脱水工艺。  相似文献   

Protein extraction from defatted wheat germ by reverse micelles: Optimization of the forward extraction   总被引：4，自引：1，他引：3  

Xiao-Hong Sun  Ke-Xue Zhu  Hui-Ming Zhou   《Journal of Cereal Science》2008,48(3):829-835

In this work, the forward extraction of defatted wheat germ protein (DWGP) by reverse micelles was studied. The reverse micellar systems were formed by sulphosuccinic acid bis (2-ethylhexyl) ester sodium salt (AOT), isooctane and KCl solution. The effects of AOT concentration, pH, KCl concentration, extraction time, the amounts of defatted wheat germ flour (DWGF), W₀ (the molar ratio of water to surfactant, i.e. W₀ = [H₂O]/[AOT]) and temperature on the forward extraction efficiency of DWGP were tested. On the basis of single-factor experiments, the optimum extraction was achieved by response surface methodology (RSM). The experimental results lead to the conclusion that the highest forward extraction efficiency of DWGP was reached at the AOT concentration 0.06 g/mL, pH 8, KCl concentration 0.1 mol/L, time 30 min, the amounts of DWGF 0.500 g, W₀ 25 and temperature 36 °C. Under these conditions, the forward extraction efficiency of DWGP achieved 37%.  相似文献