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1.
基于递归神经网络的传感器非线性动态建模   总被引:2,自引:1,他引:2  
根据动态校准实验结果建立传感器的动态数学模型,以研究传感器的动态性能,是动态测试的一个重要内容。讨论了递归神经网络模型在传感器动态建模中的应用,给出了递归神经网络模型的结构及相应的训练算法。由于其反馈特征,使得递归神经网络模型能获取系统的动态响应。该方法特别适用于传感器非线性动态建模,而且避免了传感器模型阶次的选择的困难。试验结果表明,应用递归神经网络对传感器进行动态建模是一种行之有效的方法。  相似文献   

2.
双剪切梁式力传感器的动态建模   总被引:1,自引:0,他引:1  
本文介绍了一种双剪切梁式测力传感器的工作原理及对其进行动态校准的实验方法,在时域内用基于沃尔什函数的最小二乘法对系统的校准数据进行了动态建模,获取了系统的连续传递函数。并在频域内将直接由校准数据获取的幅频谱与连续传递函数的仿真幅频谱进行了对比,两者结果是令人满意的。  相似文献   

3.
受爆炸场中寄生效应的影响,需要采取相应抑制措施对冲击波压力传感器进行改造。为研究冲击波压力传感器组件的动态特性,基于双膜激波管对冲击波压力传感器组件进行动态校准,获得了阶跃响应信号;采用微分法求取了传感器组件动态特性非参数模型;根据冲击波压力传感器组件动态特性非参数模型变化规律,在频域内对其进行合理分段,并基于BP神经网络分段建模方法得到传感器组件动态特性模型;通过实例分析与比较,证明了基于BP神经网络的分段建模方法能够有效提高模型精度和建模效率。  相似文献   

4.
对遗传算法(CA)的交叉和变异操作进行改进,提出利用改进遗传算法(ICA)和函数连接型人工神经网络(FLANN)相结合实现加速度传感器的动态建模的新方法。该方法利用加速度传感器的动态标定数据,采用IGA和FLANN相结合搜索和优化动态模型参数。文中介绍动态建模原理以及算法,给出用IGA和FLANN相结合建立的加速度传感器动态数学模型。结果表明:上面提出的动态建模方法既保留了CA的全局搜索能力和FLANN结构简单的特点,又具有网络训练速度快、实时性好、建模精度高等优点,在动态测试领域具有重要应用价值。  相似文献   

5.
针对利用单次动态校准数据建立的压力传感器动态数学模型可信度不高的问题,提出了一种估计压力传感器最优动态数学模型及评定模型不确定度的方法.首先,对同一支压力传感器进行多次动态校准、建模得到多个模型参数向量.然后,对多个模型参数向量等概率可放回地随机抽取求均值,重复抽取过程模拟大量的建模结果,以此估计压力传感器的最优动态数学模型及评定模型不确定度.最后,对该压力传感器进行多次动态校准,建模验证时域和频域模型是否落在评定的不确定度区间内.实验结果表明:该方法得到的压力传感器最优动态数学模型合理,模型不确定度符合实际且小于运用贝塞尔法、蒙特卡洛法评定的模型不确定度.  相似文献   

6.
采用静态非线性函数与动态线性环节的块连接模型来描述热线式空气质量流量(MAF)传感器的动态特性,非线性环节用多项式表示,动态线性环节采用OE模型结构.基于静、动态标定实验数据,分别建立了热线式MAF传感器在正、负阶跃激励下各校准点的Hammerstein模型,并利用非建模数据对其进行了相互验证.通过合理选择分段区间,确定出热线式MAF传感器各工作区域的最佳局部动态数学模型.模型检验结果表明:基于Hammerstein模型的分段模型比由任意一组动态数据所建模型具有更高的预测精度.  相似文献   

7.
为了提高传感器的动态测量精度,提出了一种基于改进烟花算法的动态补偿器设计方法。依据传感器输入输出的动态标定数据,运用改进后的烟花算法逆向建模获取动态补偿滤波器,以改善原传感器系统的动态性能。经仿真实验测试,验证了该方法的可行性。将方法应用于科氏质量流量计变送器的动态补偿测试。实验结果表明,基于改进烟花算法的动态补偿方法可以有效提高科氏质量流量计变送器的动态特性,动态响应时间减小了将近90%。  相似文献   

8.
腕力传感器动态补偿与解耦方法的研究   总被引:3,自引:1,他引:2  
徐科军  殷铭 《计量学报》1998,19(4):275-280
本文提出一种动态补偿与解耦方法,并解决了腕力传感器动态响应速度和各通道之间动态干扰这两个关键问题。推导出补偿解耦环节的设计公式,给出处理过程的步骤。分别对构造模型和传感器实验数据进行补偿与解耦。结果表明,这一新方法十分有效。  相似文献   

9.
姚尚金  蔡锦达 《包装工程》2015,36(13):101-103
目的 研究色标传感器的动态响应特性。方法 采用相位法测试色标传感器的动态响应特性;以嵌入式工业触摸屏为控制核心, 与色标传感器、 富士伺服电机、 伺服驱动器和编码器组成测试装置, 间接测试动态响应时间; 用MATLAB软件处理实验数据, 分析其动态特性。结果 在动态响应时间内, 根据基于触摸屏的相位法, 测得动态响应时间为2 ms, 其系统为一阶系统。结论 该测试方法简单可靠, 可以测出各种传感器的动态响应时间, 并可以判断其系统特性。  相似文献   

10.
改进PSO算法结合FLANN在传感器动态建模中的应用   总被引:4,自引:1,他引:3       下载免费PDF全文
将改进的粒子群优化(PSO)算法和函数联接型神经网络(FLANN)相结合,实现传感器的动态线性建模。利用传感器的动态标定实验数据,首先训练FLANN神经网络,网络训练结束后的权值作为粒子群中某个粒子的初始值,而后利用改进的PSO算法继续寻优,得到的全局最优值即为所求的传感器动态模型的系数。实验结果表明,该方法结合了PSO和FLANN两者的优点,建模精度高。  相似文献   

11.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

12.
13.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.  相似文献   

14.
On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……  相似文献   

15.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

16.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

17.
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill.  相似文献   

18.
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...  相似文献   

19.
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...  相似文献   

20.
Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.  相似文献   

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