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梳针刺辊与锯齿刺辊分梳差异的研究   总被引:4,自引:4,他引:0  
为研究刺辊类型、速度对纤维损伤和去除结杂的影响,用Uster AFIS单纤维测试系统,分别对三种梳针刺辊和一种锯齿刺辊在二档道夫速度和四档刺辊速度条件下所加工的生条进行了检测.结果显示:梳针刺辊在减少纤维损伤方面明显优于锯齿刺辊;梳棉机产量低时,梳针剌辊去除棉结的效果好一些,梳棉机产量高时,锯齿刺辊去除棉结的效果要好于梳针剌辊;梳棉机产量低时,大都以锯齿和梳针Ⅲ刺辊去除杂质效果好些,梳棉机产量高时,锯齿和梳针Ⅱ刺辊去除杂质效果好些.  相似文献   
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仪器缺少维修及养护直接影响测报工作的完成,以 S L1 型翻斗式遥测雨量计为例,从仪器的结构原理出发,介绍仪器的维修和养护方法,并简单论述仪器维护的重要性,提出一些搞好仪器维护的建议。  相似文献   
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As an important part of water level warning in water conservancy projects, often due to the influence of en-vironmental factors such as light and stains, the acquired water gauge images have sticky, broken and bright spot conditions, which affect the identification of water gauges. To solve this problem, a water gauge image denoising model based on improved adaptive total variation is proposed. Firstly, the regular term exponent in the adaptive total variational equation is changed to an inverse cosine function; secondly, the differential curvature is used to distinguish the image noise points and increase the smoothing strength at the noise points; finally, according to the characteristics of the gradient mode and adaptive gradient threshold after Gaussian filtering, the New model can adaptively denoise in the smooth area and protect the edge area, so as to have the characteristics of both edge-preserving denoising. The experimental results show that the new model has a great improvement in image vision, higher iteration efficiency and an average increase of 1.6 dB in peak signal-to-noise ratio, and an average increase of 9% in structural similarity, which is more beneficial to practical applications.  相似文献   
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首先对国内外梳棉机针布研究应用计算机的发展状况做了概述,之后评述针布配套研究现状,认为:国内在以往针布配套研究中,主要存在以下一些不足:(1)在针布配套中没有考虑到针布使用寿命这个参数;(2)由于选择样本数和搜集资料有限,因而建立的针布配套模型并不能代表当今世界针布配套实际,与生产实际有一定的差距;(3)建立针布专家系统所应用软件滞后于当今软件的发展。最后提出了开发针布配套专家系统的设想。  相似文献   
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基于IGA的板形板厚神经网络分散解耦PID控制   总被引:1,自引:0,他引:1  
王莉  王学秀  马云 《计算机仿真》2003,20(12):82-85,57
针对板带材轧制是一个复杂的非线性过程,板形控制(AFC)和板厚控制(AGC)又是相互耦合的一个综合系统等特点.该文首先采用神经网络分散解耦方法,对此板形板厚多变量耦合系统进行解耦,而后再应用基于免疫遗传算法的PID控制对解耦后的已近似成为两个独立的SISO系统的广义对象进行控制。从而建立了基于免疫遗传算法的板形板厚神经网络分散解耦PID控制系统。仿真结果证明了此AFC—AGC控制系统具有良好的自适应跟随和抗扰性能,其控制效果优于传统的解耦PID控制。  相似文献   
8.
张进之 《冶金设备》2004,14(1):7-11
武钢、宝钢两套冷连轧机代表了冷连轧技术发展水平 ,用连轧张力理论对这两套冷连轧机的厚控系统作了深入的分析、讨论 ,给出了其中最主要厚控环节 -连轧AGC和张力AGC的数学模型。对宝钢厚控系统提出了改进方案 ,利用DAGC可以简便地实现穿带、正常轧制、抛尾 ,而不用分别采用APC、恒压力、压力AGC三种控制方式 ,并且DAGC实现恒压力控制有更高的稳定性。  相似文献   
9.
Imetrum Video Gauge is a commercial image-based two-dimensional displacement measurement system which has been widely used. Its uncertainty analysis is presented in this paper. First, the procedure to use Video Gauge is introduced. Then, based on the measurement model, two major sources of uncertainty are identified: (1) the uncertainty associated with the calibration procedure u(C) which is composed of the uncertainty of the known length used in calibration u(L) and the uncertainty of the projection of the known length in the image u(D) and (2) the uncertainty associated with the measurement system itself u(P). Following the Guide to the Expression of Uncertainty in Measurement, the uncertainties can be quantified. In the end, 60 experiments are performed to analyze the relationship between the measurement uncertainty and the working parameters, which are working distance, acquisition frequency and focal length of the lens. In order to ensure the validity of the calculation, two calculation methods are used. The main results of this paper are as follows: (1) the displacement measurement uncertainty increases along with working distance and decreases with the increase of focal length. At the same time, the results indicate that using a longer known length in calibration can also reduce the measurement uncertainty. (2) u(C) is greatly influenced by the known length used in the calibration procedure. It can be reduced when u(L) is reduced. (3) Under the laboratory circumstances, reducing u(C) can greatly reduce the total measurement uncertainty. (4) The displacement measurement uncertainty is more sensitive to the measurement uncertainty of the known length used in calibration than the projection of the known length in the image. (5) As the working distance grows, the sensitivity to the known length is getting weaker and the sensitivity to the projection of the known length in the image is getting stronger. (6) When a longer focal length lens is used, the influence of the working distance to the sensitivity gets weaker. The reported results can help people better understand the characteristics of this system and better use the system for their own purposes.  相似文献   
10.
In this paper, we deal with some magnetostatic models considered in vector potential formulations and solved by a Finite Element solver. In order to ensure the uniqueness of the solution, a gauge condition has to be imposed, and several possibilities occur. Moreover, the source term has to be correctly defined to ensure a physically admissible solution. We show the equivalence between some of these choices for several kinds of boundary conditions. Moreover, we highlight their characteristic behaviors on some numerical benchmarks to illustrate our theoretical results.  相似文献   
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