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1.
针对海洋溶菌酶(Marine Lysozyme,ML)发酵过程菌体浓度在线检测难以实现,离线测量不能反映发酵过程当前变化等问题,提出了一种基于改进磷虾群—自适应模糊神经网络软测量(HLKH-ANFIS)建模方法。首先利用自适应莱维飞行策略对传统KH进行改进,从而提升算法的全局搜索能力;同时利用跳变技术(HOT)对KH算法位置更新公式进行改进,提高算法的局部寻优能力,然后利用改进的KH算法对自适应模糊神经网络反馈进行优化,改善其过度修正和计算量大的问题;最后建立基于HLKH-ANFIS的海洋溶菌酶发酵过程菌体浓度软测量预测模型,仿真分析表明:相较于KH-ANFIS预测模型,HLKH-ANFIS模型的误差较小,具有更好的预测能力,能够满足ML发酵关键参量的在线预测需要。  相似文献   

2.
提出一种动态调整学习率和附加梯度变化量与动量项相结合的权值优化方法,同时引入绝对误差函数用于对多层感知器中BP算法的改进,并将改进算法用于旋转机械故障诊断实例样本的学习。仿真结果表明,改进的BP算法可显著加速网络训练速度,学习过程具有较好的收敛性,并能正确地诊断出存在的故障,具有一定的实用价值。  相似文献   

3.
利用标准BP神经网络建立短期电力负荷预测模型,其算法存在最终解过于依赖初值和过学习现象,并且训练过程中存在局部极小问题且预测精度低等缺点。为了提高电力负荷模型的预测精度,通过阅读相关文献,构建了基于改进BP神经网络的短期电力负荷预测模型,该模型采用遗传算法对权值和阈值进行初始化,以相对误差和附加动量法相结合的方式去计算权值修正量。比较改进后的BP算法和标准BP算法在短期电力负荷预测的效果,从实验仿真的效果表明改进后的模型提高了预测精度。  相似文献   

4.
针对发酵过程中生物参数难以实时在线测量的问题,建立了用于生物参数状态预估的PSO-BPNN软测量模型。鉴于标准BP神经网络收敛太慢的缺点,运用PSO算法来优化网络权值,在此基础上,以饲料用β-甘露聚糖酶为对象,建立其基于PSO-BPNN的发酵过程产物浓度状态预估模型。发酵罐控制结果表明:该模型具有很好的学习精度和泛化能力,可实现对β-甘露聚糖酶产物浓度的实时在线预估。  相似文献   

5.
针对生物发酵过程中一些生物参量难以测量的问题,提出一种基于改进极限学习机(IELM)的软测量建模方法。该方法通过最小二乘方法和误差反馈原理计算出最优的网络输入到隐含层的学习参数,以提高模型的稳定性和预测精度。通过双对角化方法计算出最优的输出权值,解决输出矩阵的病态问题,进一步提高模型的稳定性。将所提方法应用于红霉素发酵过程生物量浓度的软测量。结果表明,与ELM、PL-ELM、IRLS-ELM软测量建模方法相比,IELM在线软测量建模方法具有更高的预测精度和更强的泛化能力。  相似文献   

6.
针对发酵过程中一些难以或者无法在线测量的关键物化参数和生物参数等变量,提出了改进的PSO-FNN软测量建模方案。通过改进的粒子群优化算法(PSO)寻优算法与模糊神经网络(FNN)相结合,建立发酵过程的软测量模型,再结合实际数据进行仿真研究。仿真结果表明,与传统PSO-FNN软测量相比,改进的模型测量精度更高,可以满足实际工程中的要求。  相似文献   

7.
谢丽霞  王志华 《计算机应用》2017,37(7):1926-1930
针对现有基于神经网络的网络安全态势评估方法效率低等问题,提出基于布谷鸟搜索(CS)优化反向传播(BP)神经网络(CSBPNN)的网络安全态势评估方法。首先,根据态势输入指标数和输出态势值确定BP神经网络(BPNN)的输入输出节点数,根据经验公式和试凑法计算出隐含层节点数;然后,随机初始化各层的连接权值和阈值,使用浮点数编码方式将权值与阈值编码成布谷鸟;最后,使用CS算法对权值和阈值进行优化,得到用于态势评估的CSBPNN模型并对其进行训练,将网络安全态势数据输入到CSBPNN模型中,获取网络的安全态势值。实验结果表明,与BPNN和遗传算法优化BP神经网络方法相比,基于CSBPNN的网络安全态势评估方法的迭代代数分别减少943和47且预测精度提高8.06个百分点和3.89个百分点,所提方法具有较快的收敛速度和较高的预测精度。  相似文献   

8.
支持向量机(SVM)是一种基于结构风险最小化原理(SRM)的学习算法,也是一种具有很好的泛化性能的回归方法.针对青霉素发酵过程中的菌体浓度进行软测量建模,提出了一种新的基于距离的模糊支持向量机,并用序列最小优化算法(SMO)求解优化问题.仿真实例说明能够对青霉素发酵过程中不可在线测量的变量进行软测量,达到了较高的测量精度.  相似文献   

9.
针对海洋微生物发酵过程中关键生物参量(基质浓度、菌体浓度、产物浓度等)在线测量困难,离线化验滞后大,难以实现实时控制的问题,提出了一种基于核主元分析(KPCA)与动态模糊神经网络(DFNN)相结合的软测量方法。以典型的海洋微生物-海洋蛋白酶发酵过程为例,通过KPCA提取输入数据空间中的非线性主元,将提取的主元作为DFNN的输入,基质浓度、菌体浓度、相对酶活作为DFNN的输出,建立了基于KPCA-DFNN的海洋蛋白酶发酵过程生物参量软测量模型。仿真结果表明,KPCA-DFNN模型比DFNN和PCA-DFNN建模的测量精度高,跟踪性能强,能很好地满足发酵过程中生物参量的测量要求。  相似文献   

10.
针对生物发酵过程中一些生物参量难以用仪表进行在线检测的问题,提出一种基于连续隐Markov模型(CHMM)的发酵过程软测量建模方法.为减少建模过程的计算量,提出了改进最小分类误差准则,用于CHMM软测量模型参数估计.为避免软测量结果在发酵过程监测与控制实际应用中存在的盲目性,提出了在线评价软测量结果可靠性的可信度评价指标.实验结果表明了所提出方法的有效性以及可信度评价指标的实际意义.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.  相似文献   

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