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为对脱籽后原棉的短纤指数进行预测,采用遗传优化BP神经网络预测法,设计了原棉短纤指数预测的遗传优化BP神经网络模型。以南疆地区原棉为研究对象,选择籽棉回潮率和轧花速度频率2个因素作为BP神经网络模型的输入量,利用遗传算法优化神经网络的权值与阈值,建立原棉短纤指数的遗传BP神经网络预测模型。结果表明,遗传BP神经网络模型能较好地表达原棉短纤指数与主控因素之间的非线性关系,预测结果与实测值之间误差小,测试样本的网络输出值与网络目标值的相关系数达0.999 8,模型预测效果较佳。 相似文献
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为了降低机采棉清理工序对纤维品质的损伤程度,通过比较不同清理加工工序间纤维品质的差异,分析了籽棉清理和皮棉清理工序对纤维品质的损伤程度,探讨了最大限度降低纤维品质损伤的适宜机采棉清理道数。研究表明:机采棉每道清理工序均会对纤维品质造成损伤;籽棉清理对纤维断裂比强度的影响较大,较清理加工前平均降低了1.0 c N/tex,且以第2、3道工序的损伤最大;皮棉清理工序使纤维长度和整齐度下降了0.8 mm和1.7%,短纤维率增加了2.0%;第1道皮棉清理工序(含轧花工序)对纤维的损伤最大;籽棉清理工序可根据机采籽棉叶杂的清除难易程度,选择使用1~2道;皮棉清理可选择1道气流式皮棉清理机,或尝试不使用皮棉清理机。 相似文献
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棉花性能指标对成纱质量的预测模型研究 总被引:1,自引:0,他引:1
《棉纺织技术》2016,(6)
探讨基于遗传算法和主成分分析法与BP神经网络相结合的棉花性能指标对成纱质量的预测模型。分别采用单一BP神经网络(模型1)、主成分分析加BP神经网络(模型2)、主成分分析加遗传算法优化隐层节点数后的BP神经网络(模型3),依据实测原棉数据对成纱品质作预报,并以平均相对误差百分率指标最小为原则,对比了三种模型的优劣。结果表明:模型3的平均相对误差百分率值最小;主成分分析表面上在降维,但对神经网络来说仍是高维的计算,最优结果的隐层节点数均高于经验公式确定的隐层节点数,接近于13个原始变量数。认为:基于遗传算法和主成分分析法与BP神经网络相结合进行预报,能够使预测精度得到明显提高。 相似文献
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为保障大米质量安全,提出一种基于BP神经网络的大米品质检测方法。方法以大米水分含量作为大米品质指标,通过结合粒子群优化算法(PSO)和遗传算法(GA)优化BP神经网络的阈值和权值,实现了BP神经网络的改进,提高BP神经网络的收敛速度,解决BP神经网络容易陷入局部最优的问题。然后,将改进的BP神经网络应用于大米水分含量预测中,实现了大米水分含量的准确预测。仿真结果表明,所提的改进BP神经网络模型相较于标准BP神经网络模型和LSTM-BP神经网络模型,在预测集和验证集上的均方根误差更小,分别为0.007和0.005,其大米水分含量预测值与真实值接近,可准确检测大米水分含量,为大米品质检测奠定了理论基础。 相似文献
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新疆机采棉与手摘棉的成本质量对比研究 总被引:3,自引:0,他引:3
对比新疆生产建设兵团机采棉与手摘棉的成本和质量。介绍了机采棉的发展现状及发展趋势,从棉花品质、构成成本、经济效益等方面对机采棉与手摘棉进行了对比。指出:机采棉品质稍差;机采棉成本构成共8项,合计13 305元/hm2,折合到籽棉成本2.53元/kg;手摘棉成本构成共5项,合计15 840元/hm2,折合到籽棉成本3.02元/kg;机采棉比手摘棉节约成本0.49元/kg。认为:机采棉综合成本明显偏低,具有竞争优势。建议新疆生产建设兵团应积极选育机采棉新品种、扩大种植面积,提升加工水平、原棉品质,从而进一步提高机采棉的经济效益。 相似文献
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为研究南美白对虾品质指标与货架期之间的关系及南美白对虾在贮藏过程中的品质变化过程,精确预测其剩余货架期,通过检测277,272.2,255K温度下南美白对虾的感官指标、理化指标和微生物指标,分别针对南美白对虾品质检测的综合指标和部分关键指标,以支持向量机模型和BP神经网络模型为基础,建立南美白对虾货架期预测模型。结果表明:基于综合指标构建的货架期预测模型的预测精度(支持向量机为97.71%,BP为91.41%)比基于关键指标的(支持向量机为84.08%,BP为83.76%)高;基于支持向量机的预测模型的预测精度(关键指标为84.08%,综合指标为97.71%)比BP预测模型的(关键指标为83.76%,综合指标为91.41%)高;基于综合指标的支持向量机预测模型的预测精度是4种模型中最高的,为97.71%。该结论也可为支持向量机方法和预测指标选择在其他食品领域货架期的应用研究提供一定的参考。 相似文献
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使用HVI测试原棉指标和USTER TENSOJET 4测试成纱指标.分别用标准BP、LMBP算法建立断裂伸长预测的神经网络模型,进行纱线的断裂伸长预测,结果表明LMBP算法建立的模型预测速度和精度明显高于标准的BP算法. 相似文献
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Kym Anderson 《Journal of Wine Research》2016,27(3):173-192
In an ever-more-competitive global market, vignerons compete for the attention of consumers by differentiating their product while responding to technological advances, climate changes and evolving demand patterns. In doing so, they increasingly highlight their regional and varietal distinctiveness. This paper examines the extent to which the mix of winegrape varieties in Australia differs from the rest of the world and differs across wine regions within the country, and how that picture has altered over the first decade of this century. It reports varietal intensity indexes for different regions, indexes of similarity of varietal mix between regions and over time, and quality indexes across regions and varieties within Australia. The study is based mainly on a new global database of vine bearing areas circa 2000 and 2010, supplemented by a more detailed database for Australia back to the 1950s. It reveals that the varietal distinctiveness of Australia vis-à-vis the rest of the world, and varietal differentiation between regions within the country, is far less than for most other countries – a pattern that has become even more pronounced since 2000. It concludes that there is much scope for Australia’s winegrape plantings to become more diversified as producers respond to market and climate changes. 相似文献
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研究了在体重过多人群的食生活里导入杂粮的有效性以及杂粮食谱的营养价值。营养价值参考了日本厚生劳动省发表的"日本人食事摄取基准",这资料标示了目标热量、各种营养成分的目标摄取量以及许多项目的极限程度。因为极限程度与年龄、性别和生理状态有关,在此我们以普通生活的成人作为基准。杂粮中的营养成分,苋的热量358kcal、蛋白质12.7g、脂肪6.0g、糖质64.9g、食物纤维7.4g、Na 1.0mg、P540mg、Fe 9.4mg、Ca 160mg、K 600mg、Cu 0.92mg、Zn 5.8mg、Mn 6.14mg、维生素A 2.0ug以及微量的维生素C。经过研讨设计了营养平衡最佳的食谱为:糙米200g、苋50g、andeskinua50g、大豆110g、甘薯200g、绿黄色蔬菜(小青菜)300g、鸡蛋55g以及泥鳅100g。食用这个食谱可以摄取热量2007 kcal(是基准摄取量的100%),其他营养成分的摄取量与基准摄取量相比分别为:蛋白质173%、脂肪72%、碳水化物105%、K 332%、Ca262%、Mg 267%、P 250%、Fe 420%、Zn 183%、Cu 343%、VA 126%、VD 100%、VE 142%、VK 940%、VB1237%、VB2174%、烟碱酸201%、VB6218%、VB12375%、叶酸350%、泛酸160%、VC 176%、食物纤维185%、盐分5%以及Mn 273%。不足的盐分可以使用调味料来补充。氨基酸的摄取量推测是基准值的100%。蛋白质:脂肪:碳水化物的比例是19.0∶18.0∶63.0,与理想的平衡比接近。 相似文献
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讨论纺纱纤维混和问题.通过分析纺纱纤维混和的理念、纤维混和的方法、纤维微观混和指标、纤维宏观混和指标的概念和测试方法,指出了纤维堆混和、纤维束混和、筵棉多仓立体混和及纤维条混和的特点;介绍了组分纤维混和指标及测试分析方法的作用和意义.举例说明了低比例称重混和的计算方法. 相似文献
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Background and Aims: We investigated the effectiveness of shoot topping and 2-chlorethyltrimethyl-ammonium chloride (CCC) application on the control of fruitset and other yield components on the grapevine varieties Cabernet Sauvignon, Chardonnay and Tempranillo at two sites over two or three seasons.
Methods and Results: Treatments were applied before and during the flowering period. Fruitset and yield per vine increased in response to both shoot topping and CCC treatment, especially when shoot topping was applied between E–L stages 19 and 23, and when CCC was applied 1 week before flowering. All varieties at both locations responded to shoot topping to some degree: from 20 to 57% relative to the control for fruitset and from 16 to 97% for yield per vine.
Conclusions: Fruitset, and, thus, yield, can be improved by cultural practices in all seasons, but the magnitude of the response may be greatest in those seasons when fruitset is lower than the average. Neither berry number per bunch nor the visual appearance of the bunches were reliable indicators of fruitset performance.
Significance of the Study: Optimal timing of shoot topping and CCC application as cultural practices is critical to maximise the response. The 'Coulure Index' and the 'Millerandage Index', which are described for the first time, are novel and useful indicators of fruitset that have been developed to quantify the reproductive performance of grapevines. 相似文献
Methods and Results: Treatments were applied before and during the flowering period. Fruitset and yield per vine increased in response to both shoot topping and CCC treatment, especially when shoot topping was applied between E–L stages 19 and 23, and when CCC was applied 1 week before flowering. All varieties at both locations responded to shoot topping to some degree: from 20 to 57% relative to the control for fruitset and from 16 to 97% for yield per vine.
Conclusions: Fruitset, and, thus, yield, can be improved by cultural practices in all seasons, but the magnitude of the response may be greatest in those seasons when fruitset is lower than the average. Neither berry number per bunch nor the visual appearance of the bunches were reliable indicators of fruitset performance.
Significance of the Study: Optimal timing of shoot topping and CCC application as cultural practices is critical to maximise the response. The 'Coulure Index' and the 'Millerandage Index', which are described for the first time, are novel and useful indicators of fruitset that have been developed to quantify the reproductive performance of grapevines. 相似文献
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浅议甘蔗糖蜜酒精生产技术考核指标 总被引:2,自引:0,他引:2
不同地区糖蜜酒精生产厂采用的生产技术考核指标差别较大,每种考核指标各有优劣,要结合各厂实际情况灵活选择,对配备有糖蜜计量设备的厂,最好采用标蜜单耗或吨酒耗糖分来考核酒精生产。 相似文献
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通过测定绝对电导率、接触电导率和饱和温度实验,研究了4种葡萄酒快速冷处理前后的酒石稳定性变化。结果发现,由于生态条件的差异,快速冷处理后进口设备商提供的酒石稳定性评判标准不适合我国葡萄酒生产的实际;多糖对红白葡萄酒的酒石稳定影响明显,红葡萄酒中的另一些组分(如酚类物质)对酒石沉淀也有重要影响作用;冷稳定处理除沉淀了较多的酒石酸和钾离子外,还沉淀了少量的钙离子,甜白葡萄酒钙离子的减少量比干红葡萄酒显著。 相似文献
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