集成随机配置网络在养殖水质监测中的应用

2020-04-10 07:30王奕鹏
农业工程学报 2020年4期
关键词:氨氮水体神经网络

李 康,王 魏,王奕鹏

集成随机配置网络在养殖水质监测中的应用

李 康,王 魏※,王奕鹏

(大连海洋大学信息工程学院,大连 116023)

为解决集约化水产养殖过程水体氨氮浓度无法实时检测的问题,提出基于Bagging集成随机配置网络(stochastic configuration network,SCN)的建模方法,利用养殖过程采集的相关水质参数对养殖水体氨氮浓度进行软测量。该方法首先采用Bootstrap方式生成多个不同的训练子集,然后并行训练多个SCN模型,最后将各个SCN模型的输出结果取均值作为Bagging-SCN模型的输出。为验证方法的有效性,分别通过UCI标准数据库中的机翼自噪声数据集和集约化海水养殖过程数据集进行了仿真试验,将该研究提出的Bagging-SCN模型与单一SCN模型、以及目前应用最广泛的随机权向量函数连接网络(random vector functional-link net,RVFL)模型、Bagging-RVFL模型的测量效果进行了比较。试验结果表明:该文所提模型对机翼自噪声数据集中缩放声压级测量的均方根误差、平均绝对百分比误差和最大绝对误差分别为4.225 dB、2.599 %和17.500 dB;在对集约化海水养殖过程中水体氨氮浓度测量的均方根误差、平均绝对百分比误差和最大绝对误差分别为0.062 8 mg/L、27.851 mg/L和0.189 mg/L均优于其他测量模型;进一步说明该模型具有较高的测量精度和稳定性,更适合应用于集约化水产养殖水质监测过程。

软测量;集成学习;随机配置网络;氨氮浓度;水质监测

0 引 言

在水产养殖过程中,氨氮浓度是衡量养殖水体水质的重要指标[1-3]。养殖水体氨氮浓度过高,不仅对水生生物的生存状态造成巨大影响,还可能会对周边的生态环境造成严重破坏[4-5]。近年来,随着工业化、信息化技术的不断进步,水产养殖模式也朝着集约化、精细化的方向发展[6-9]。良好的水质环境,是保证水产养殖收益的基础,但高密度的养殖模式会加快养殖水质的恶化[10-11],因此在集约化养殖过程中实现对养殖水体氨氮浓度的实时有效测量显得尤为重要。

国内外学者利用数据驱动的软测量建模方法,对水体氨氮浓度的测量进行了大量的研究。如高艳萍等[12]基于BP神经网络对养殖水体氨氮浓度进行预测。Deng等[13]提出基于RBF的软测量方法在线测量水体氨氮浓度。于辉辉[14]采用极限学习机对养殖水体氨氮浓度进行软测量。乔俊飞等[15-16]分别基于RBF和递归RBF神经网络对污水处理过程出水氨氮进行预测。这些方法很好的解决了传统测量氨氮浓度(如纳氏试剂法)存在的测量过程复杂、测量周期长、成本高等问题。然而,这些软测量模型由于算法本身的局限性,很难实现快速高效的逼近性能,在处理大规模数据时具有一定的局限性。

近年来,随着随机权神经网络的不断发展,Wang等[17]提出的随机配置网络(stochastic configuration network,SCN)由于其特有的学习机制,在快速学习的情况下,很好的保证了网络较高的逼近性能,并因此得到了广泛应用[18-22]。王魏等[23]采用SCN模型对养殖水体氨氮浓度进行预测,并得到较好的效果。然而,在SCN模型建立的过程中,网络权重的随机初始化以及网络结构的不确定性会导致网络输出结果的不稳定。考虑到Bagging集成方法可以通过集成多个不同的子模型,在保证模型偏差不变的条件下,有效降低集成后模型的方差,进一步提高模型的泛化性能。因此,本研究提出基于Bagging集成的SCN建模方法,该方法首先利用Bootstrap的采样方式生成多个不同的训练集,然后基于不同的训练集训练生成不同的SCN模型,并将多个网络模型进行集成,通过UCI标准数据库中的机翼自噪声数据集验证了方法的有效性。最后,将所提模型应用于集约化养殖水体氨氮浓度的软测量。试验结果表明,该模型在测量水产养殖过程水体氨氮浓度时,不仅能够提高氨氮浓度的测量精度,还具有较高的稳定性。

1 随机配置网络(SCN)算法概述

随着工业信息化技术的不断发展,数据规模的不断增加,随机权神经网络在处理大规模数据时的有效性以及快速学习等优势逐渐显现[24]。与传统梯度类神经网络相比,随机权神经网络由于本身特有的学习方式,在保证模型逼近能力的情况下,很好的避免了网络参数迭代调整的过程,大幅度提高了模型的学习效率,而且很好的克服传统梯度类算法本身所固有的收敛速度慢,易陷入局部极小等问题,是近年来神经网络领域一个重要的研究热点[25]。然而,随机权神经网络在数据建模方面存在着一些问题。Tyukin等[26]通过实验表明,当随机参数的设置不合适时,随机权向量函数连接网络(random vector functional-link net,RVFL)不能以极高的概率逼近目标函数。Li等[27]揭示了增量式RVFL网络的不可行性,并且Wang和Li[17]提出了一种基于监督机制的SCN模型,保证了随机权神经网络在数据建模时的通用逼近能力,其基本的网络结构如图1所示。

图1 SCN基本网络结构图

SCN是一个典型的单隐含层前馈神经网络,与传统的单隐含层前馈神经网络相比,SCN可在人为很少干预的情况下,从一个小型网络开始,随机的选取输入权值和阈值,逐渐增加隐含层神经元节点的数量并利用最小二乘法求出输出权值和偏置,直到网络的训练精度满足终止条件。此外,SCN还针对随机参数增加了不等式约束条件,根据随机参数的大小,自适应的选择随机参数的取值范围,进一步确保随机化学习模型的通用逼近性[17]。

图2 SCN算法基本流程图

2 Bagging-SCN算法研究

集成学习是多种模型融合方法的统称,通过构建并结合多个学习器来完成任务[28]。虽然集成学习的具体算法和策略各不相同,但都具有相同的基本步骤。首先生成一组相互独立的基学习器,然后对基学习器进行训练并按照某种结合策略将多个基学习器进行集成[29]。本研究采用集成学习方法中常见的Bagging并行集成方法,该方法由Breiman[30]于1996年提出,从一个给定的数据集中采用Bootstrap的方式采样生成个样本集,然后基于每一个样本集训练出一种基学习器,最后将这些基学习器进行集成。这种方式能够降低模型输出的方差,提高模型的泛化性能,且并行训练的方式能节省大量的时间成本。

对于Bagging而言,基学习器的稳定性是能否有效提高模型性能的主要因素。要使模型通过Bagging集成后能够大幅提高模型的测量精度和泛化性能,最重要的一点是要保证Bagging算法中基学习器之间具有一定的独立性和差异性。由于SCN网络对于训练数据具有较强的逼近能力,其独特的训练方式给模型添加了不少的随机性。采用Bootstrap方式进行采样,使得不同的基学习器选用的训练集样本各不相同,进一步增加了SCN模型训练时的差异性,从而提高了模型的泛化性能。因此,综合2种算法的特点,提出基于Bagging-SCN的方法,流程如图3所示。

图3 Bagging-SCN基本流程图

训练集采用Bootstrap的方式进行采样,生成个训练子集,利用不同的训练子集训练生成不同的SCN模型,并将该子集中未被采集到的样本作为各基学习器的验证集,用于验证各个模型性能。最后将所有基学习器的输出取平均作为最终模型的输出,利用测试集来对最终模型进行评估。算法步骤描述如下:

输入:训练样本集、基学习器个数、基本SCN算法

输出:集成学习器()

方法:

1)For=1 to

2)利用Bootstrap的方式从训练集中有放回的抽取出与相同大小的训练子集

3)基于不相同的训练子集训练对应的SCN算法,得到基学习器r()

4)End for

5)组合个SCN模型,输出集成学习

3 仿真试验与结果分析

本部分主要对2个不同背景的数据集进行试验。采用SCN、Bagging-SCN、RVFL以及Bagging-RVFL方法进行仿真,并通过均方根误差(root mean square error,RMSE),平均绝对百分比误差(mean absolute percentage error,MAPE),最大绝对误差(maximum absolute error,MAE)3种不同的评价指标对上述不同模型的测量性能进行比较。

3.1 机翼自噪声数据集仿真

3.1.1 数据描述

选用University of California Irvine(UCI)数据库提供的机翼自噪声[31]数据集。该数据集通过在消声风洞中对二维和三维翼型叶片截面进行一系列空气动力学和声学测试获得,共包含1 503个数据样本,其中前5列作为网络的输入,分别是频率、迎角、弦长、自由流速度、吸入侧位移厚度,第6列为输出,即缩放声压级,单位dB。本研究随机取1 200个样本作为训练集,剩余303个样本作为测试集,部分历史数据如表1所示。

表1 机翼自噪声部分历史数据

3.1.2 仿真试验

利用本研究所提方法建立Bagging-SCN模型来对缩放声压级进行测量,该模型每个基学习器SCN模型的训练误差与隐含层神经元的个数关系如图4所示。

图4 SCN节点个数与训练误差下降关系曲线

基学习器个数与模型输出误差下降的关系曲线图,如图5所示。随着基学习器个数的增加,模型的输出RMSE逐渐下降并趋于平缓。为了避免网络模型过于复杂,本研究选取50个基学习器,其中每个基学习器的最大隐含层神经元个数为15,最大预选隐含层神经元个数为100,网络每次递增1个隐含层节点。Bagging-SCN模型对于机翼自噪声数据的缩放声压级的测量效果如图6所示。模型测量值与真实值关系的散点图如图7所示。

图5 基学习器个数与误差下降关系曲线

为验证所提方法的有效性,在输入特征数据与网络最大隐含层神经元节点个数完全相同的条件下,将其测量效果与SCN、RVFL、Bagging-RVFL的测量效果进行对比,其中Bagging-RVFL模型中基学习器的个数也为50个。

图6 Bagging-SCN模型测试结果曲线图

图7 Bagging-SCN测量值与真实值关系散点图

为方便对比不同模型对机翼自噪声数据的缩放声压级的测量效果,分别将Bagging-SCN模型,单一SCN模型,Bagging-RVFL模型以及单一RVFL模型对缩放声压级进行连续测量20次,统计各模型训练和测试结果如表 2所示。

3.1.3 试验结果分析

由表2可知,SCN模型的测量性能优于RVFL模型,Bagging-SCN和Bagging-RVFL 模型的训练和测试效果在精度和稳定性方面优于单一模型,说明集成后的模型具有更好的性能。

3.2 养殖水质氨氮浓度软测量仿真试验

3.2.1 数据采集预处理

利用实验室集约化循环养殖系统,以大菱鲆为养殖对象,通过养殖水箱安装的不同水质参数传感器采集数据,实现集约化养殖过程水质监测。基于王魏和郭戈[23]分析的结果,本研究将传感器采集到的溶解氧、水温、pH、电导率作为辅助变量,对氨氮浓度进行软测量建模,它们与氨氮浓度之间的相关性大小分别为0.681、0.306、0.274、0.132。试验采集到227组试验数据,其中氨氮浓度由化学测试方式获得。部分历史数据如表3所示。由于采集到的不同特征对应的数据值差别较大,因此首先将数据进行归一化处理,消除不同量纲对模型拟合效果的影响。

表2 缩放声压级测量结果比较

表3 所选水质参数的部分历史数据

3.2.2 仿真试验与结果分析

将采集到的数据进行预处理,随机选取前150组数据作为训练集,采用本研究提出的Bagging-SCN方法建立氨氮软测量模型,并将剩余的77组数据作为测试集评估模型的测量性能。如图8所示,为Bagging-SCN模型的水体氨氮浓度测量结果图。为了验证所提方法的有效性,将结果与单个SCN,Bagging-RVFL与单个RVFL网络对养殖水体氨氮浓度的测量效果进行对比。各模型的参数设置与3.1节模型参数设置完全相同。

图8 Bagging-SCN模型的氨氮浓度测量结果

同样将各种算法进行连续20次测量,统计各模型的测量结果,如表4所示。

表4 氨氮浓度测量结果比较

观察表4结果可知,单一的SCN比RVFL有较好的泛化性能,Bagging-RVFL比单一RVFL模型具有较高的测量精度和稳定性。与其他模型相比,Bagging-SCN模型的在测量集约化海水养殖水体氨氮浓度中具有最优的测量效果。

4 结 论

本研究利用Bagging集成算法能够有效降低模型方差的优点,将其与SCN模型结合,提出基于Bagging-SCN的集成模型。该模型解决了SCN模型在建立过程中因网络参数和结构的随机化,致使模型测量性能不稳定的问题。通过UCI平台的机翼自噪声数据集验证了所提模型的有效性。最后将该模型应用于集约化养殖水体氨氮浓度软测量。通过对比单一SCN、RVFL和Bagging-RVFL、Bagging-SCN模型的测量效果,可知Bagging-SCN模型在测量养殖水体氨氮浓度时的均方根误差和最大绝对误差都较小,表明本研究所提Bagging-SCN模型进一步提高了集约化养殖水体氨氮浓度模型的泛化性和稳定性,对养殖水体监测具有一定的指导意义。

[1]陈英义,成艳君,杨玲,等. 基于改进深度信念网络的池塘养殖水体氨氮预测模型研究[J]. 农业工程学报,2019,35(7):195-202. Chen Yingyi, Cheng Yanjun, Yang Ling, et al. Prediction model of ammonia-nitrogen in pond aquaculture water based on improved multi-variable deep belief network[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2019, 35(7): 195-202. (in Chinese with English abstract)

[2]刘双印. 基于计算智能的水产养殖水质预测预警方法研究[D]. 北京:中国农业大学,2014. Liu Shuangyin. Prediction and Early-Warning of Water Quality in Aquaculture Based on Computational Intelligence[D]. Beijing: China Agricultural University, 2014. (in Chinese with English abstract)

[3]李康,王魏,林少涵. 基于GA-SVR的海水养殖过程软测量建模[J]. 控制工程,2019,26(11):2047-2051. Li Kang, Wang Wei, Lin Shaohan. Soft sensor for intensive aquaculture process based on GA-SVR[J]. Control Engineering of China, 2019, 26(11): 2047-2051. (in Chinese with English abstract)

[4]蔡继晗,沈奇宇,郑向勇,等. 氨氮污染对水产养殖的危害及处理技术研究进展[J]. 浙江海洋学院学报:自然科学版,2010,29(2):167-172,195. Cai Jihan, Shen Qiyu, Zheng Xiangyong, et al. Advancement in researches of ammonia pollution hazards on aquaculture and its treatment technology[J]. Journal of Zhejiang Ocean University (Natural Science), 2010, 29(2): 167-172, 195. (in Chinese with English abstract)

[5]张卫强,朱英. 养殖水体中氨氮的危害及其检测方法研究进展[J] 环境卫生学杂志,2012,2(6):324-327. Zhang Weiqiang, Zhu Ying. Advances on the research of the hazard of ammonia nitrogen in aquaculture water and its determination method[J]. Journal of Environmental Hygiene, 2012, 2(6): 324-327. (in Chinese with English abstract)

[6]Martins C I M, Eding E H, Verdegem, M C J, et al. New developments in recirculating aquaculture systems in Europe: A perspective on environmental sustainability[J]. Aquacultural Engineering, 2010, 43(3): 83-93.

[7]董双林. 论我国水产养殖业生态集约化发展[J]. 中国渔业经济,2015,33(5):4-9. Dong Shuanglin. On the ecological intensification of aquaculture industry in China[J]. China Fisheries Economics. 2015, 33(5): 4-9. (in Chinese with English abstract)

[8]段青玲,刘怡然,张璐,等. 水产养殖大数据技术研究进展与发展趋势分析[J]. 农业机械学报,2018,49(6):1-16. Duan Qingling, Liu Yiran, Zhang Lu, et al. Analysis of research progress and development trend of big data technology in aquaculture[J]. Transactions of the Chinese Society for Agricultural Machinery. 2018, 49(6): 1-16. (in Chinese with English abstract)

[9]刘鹰. 海水工业化循环水养殖技术研究进展[J]. 中国农业科技导报,2011,13(5):50-53. Liu Ying. Research progress on marine industrial recirculating aquaculture technology[J]. Journal of Agricultural Science and Technology, 2011, 13(5): 50-53. (in Chinese with English abstract)

[10]McKenzie D J, Höglund E, Dupont-Prinet A, et al. Effects of stocking density and sustained aerobic exercise on growth, energetics and welfare of rainbow trout[J]. Aquaculture, 2012, 216-222.

[11]高霄龙,刘鹰,李贤,等. 鲍放养密度对循环水养殖水质的影响及生物滤器净化效果[J]. 农业工程学报,2017,33(21):244-252. Gao Xiaolong, Liu Ying, Li Xian, et al. Effects of stocking density on water quality of Haliotis discus hannai Ino in recirculating aquaculture and purification effect of biofilter[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2017, 33(21): 244-252. (in Chinese with English abstract)

[12]高艳萍,周敏,姜凤娇. 基于 BP 网络养殖水体氨氮预测模型及实现[J]. 农机化研究,2008(7):48-50. Gao Yanping, Zhou Min, Jiang Fengjiao. Prediction model and implementation of ammonia nitrogen in aquaculture water based on BP network[J]. Journal of Agricultural Mechanization Research, 2008(7): 48-50. (in Chinese with English abstract)

[13]Deng Changhui, Kong Deyan, Song Yanhong, et al. A soft-sensing approach to on-line predicting ammonia nitrogen based on RBF neural networks[C]. International Conferences on Embedded Software and Systems, 2009, 454-458.

[14]于辉辉. 基于机器学习的池塘养殖水质关键因子预测方法研究[D]. 北京:中国农业大学,2018. Yu Huihui. Prediction Research of Water Quality in Aquaculture Based on Machine Learning Method[D]. Beijing: China Agricultural University, 2018. (in Chinese with English abstract)

[15]乔俊飞,安茹,韩红桂. 基于RBF神经网络的出水氨氮预测研究[J]. 控制工程,2016,23(9):1301-1305. Qiao Junfei, An Ru, Han Honggui. Water ammonia nitrogen prediction research based on RBF neural network[J]. Control Engineering of China, 2016, 23(9): 1301-1305. (in Chinese with English abstract)

[16]乔俊飞,马士杰,许进超. 基于递归RBF神经网络的出水氨氮预测研究[J]. 计算机与应用化学,2017,34(2):145-151. Qiao Junfei, Ma Shijie, Xu Jinchao. Prediction of ammonia nitrogen based on recurrent RBF neural network[J]. Computers and Applied Chemistry, 2017, 34(2): 145-151. (in Chinese with English abstract)

[17]Wang Dianhui, Li Ming. Stochastic configuration networks: Fundamentals and algorithms[J]. IEEE Transactions On Cybernetics, 2017, 47(10): 3466-3479.

[18]王前进,杨春雨,马小平,等. 基于随机配置网络的井下供给风量建模[J/OL]. 自动化学报,2019,1-12. Wang Qianjin, Yang Chunyu, Ma Xiaoping, et al. Underground airflow quantity modeling based on SCN[J/OL]. Acta Automatica Sinica, 2019, 1-12. https://doi.org/ 10.16383/j.aas.c190602. (in Chinese with English abstract)

[19]盛智勇,曾志强,曲洪权,等. 基于随机配置网络的光纤入侵信号识别算法[J]. 激光与光电子学进展,2019,56(14):47-54. Sheng Zhiyong, Zeng Zhiqiang, Qu Hongquan, et al. Fiber intrusion signal recognition algorithm based on stochastic configuration network[J]. Laser and Optoelectronics Progress, 2019, 56(14): 47-54. (in Chinese with English abstract)

[20]Dai Wei, Li Depeng, Chen Qixin, et al. Data driven particle size estimation of hematite grinding process using stochastic configuration network with robust technique[J]. Journal of Central South University, 2019, 26(1): 43-62.

[21]代伟,李德鹏,杨春雨,等. 一种随机配置网络的模型与数据混合并行学习方法[J/OL]. 自动化学报,2019,1-12. Dai Wei, Li Depeng, Yang Chunyu, et al. A model and data hybrid parallel learning method for stochastic configuration networks[J/OL]. Acta Automatica Sinica, 2019, 1-12. https://doi.org/10.16383/j.aas.c190411. (in Chinese with English abstract)

[22]Li Ming, Wang Dianhui. 2-D stochastic configuration networks for image data analytics[J]. IEEE Transactions on Cybernetics, 2018, 1-14. https://arxiv.org/pdf/1809.02066v1.pdf

[23]王魏,郭戈. 基于随机配置网络的海水养殖氨氮浓度软测量模型[J/OL]. 农业机械学报,2020,51(1):214-220. Wang Wei, Guo Ge. Soft measurement model for ammonia nitrogen concentration in marine aquaculture based on stochastic configuration networks[J/OL]. Transactions of the Chinese Society for Agricultural Machinery, 2020, 51(1): 214-220. http://kns.cnki.net/kcms/detail/11.1964. S.20191112.0944.006.html. (in Chinese with English abstract)

[24]Scardapane S, Wang Dianhui. Randomness in neural networks: An overview[J]. Wiley Interdisciplinary Reviews: Data Mining and Knowledge Discovery, 2017, 7(2): e1200.

[25]乔俊飞,李凡军,杨翠丽. 随机权神经网络研究现状与展望[J]. 智能系统学报,2016,11(6):758-767. Qiao Junfei, Li Fanjun, Yang Cuili. Review and prospect on neural networks with random weights[J]. CAAI Transactions on Intelligent Systems, 2016, 11(6): 758-767. (in Chinese with English abstract)

[26]Tyukin I Y, Prokhorov D V. Feasibility of random basis function approximators for modeling and control[C]. IEEE Control Applications (CCA) & Intelligent Control (ISIC), 2009, 1391-1396.

[27]Li Ming, Wang Dianhui. Insights into randomized algorithms for neural networks: Practical issues and common pitfalls[J]. Information Sciences, 2017, 382: 170-178.

[28]周志华. 机器学习[M]. 北京:清华大学出版社. 2016.

[29]诸葛越. 百面机器学习[M]. 北京:人民邮电出版社. 2018.

[30]Breiman L. Bagging predictors[J]. Machine Learning, 1996, 24(2): 123-140.

[31]Dua D, Graff C. UCI machine learning repository[J]. Irvine, CA: University of California, School of Information and Computer Science. 2019.

Application of ensemble stochastic configuration network in aquaculture water quality monitoring

Li Kang, Wang Wei※, Wang Yipeng

(,,116023,)

Ammonia nitrogen concentration is an important parameter to evaluate the quality of aquaculture water, and it determines the yield and benefits of intensive aquaculture production. In order to solve the problems of high cost, high consumption and difficulty in real-time and effective detection of ammonia nitrogen concentration, a method combining bagging ensemble algorithm and stochastic configuration network (SCN) which called Bagging-SCN were proposed. In this method, according to the current development of ammonia nitrogen measurement methods and random neural networks technology, SCN was chosen as the base learner due to its advantages of fast learning speed and strong ability to approach training data. The bagging ensemble method was used to integrate multiple networks, which effectively reduced the variance of the integrated model under the condition of keeping the model deviation unchanged. Specifically, the bootstrap method was used to generate multiple different training subsets for parallel training of multiple SCN models, and then different SCN models were generated by training with different subsets, and the uncollected samples in this subset were used as the verification set of each base SCN model to verify the performance of each model. Finally, the outputs of all base SCN models were averaged as the output of the final model, and the test set was used to evaluate the final model. In the modeling process of base learners, the SCN model started from a small network with little human intervention and randomly selected input weights and thresholds based on inequality constraints. It adaptively selected the value range of the random parameters according to the size of the random parameters to further ensure the universal approximation of the randomized learning model. The bagging method solved the problem that the randomization of network parameters and the uncertainty of network structure lead to the instability of measurement effect in the process of SCN modeling, and improved the measurement accuracy and stability of the model. To verify the validity of the proposed method, the experiments were mainly performed using two data sets with different backgrounds. The first experiment was based on the airfoil self-noise data set in the UCI standard database, and the frequency, angle of attack, chord length, free-stream velocity, and suction side displacement thickness was chosen as the auxiliary variables for modeling of scaled sound pressure level. The soft sensing modeling method of Bagging-SCN, SCN, random vector functional link net (RVFL) and Bagging-RVFL were carried out respectively based on the data set, for 20 consecutive times, and the output results of each model were statistically analyzed. These algorithms were verified by comparing the mean of the root mean square error (RMSE), the mean of the maximum absolute error (MAE) and the mean of the average absolute percentage error (MAPE) of the output predicted by different models, and the experimental results showed that the proposed Bagging-SCN model had a certain improvement in measurement accuracy and stability and had the best measurement performance compared with other models. The data set in the second experiment was collected by our laboratory intensive aquaculture system, and the proposed method was applied to the soft-sensing of ammonia-nitrogen concentration in intensive aquaculture. The relevant water quality parameters such as water temperature, pH, dissolved oxygen, conductivity which collected by sensors in the laboratory system were used as auxiliary variables for modeling of ammonia nitrogen concentration. Experiments with comparisons on the prediction effect of Bagging-SCN, SCN, Bagging-RVFL and RVFL models were carried out as the first experiment. Results indicated that the proposed algorithm had higher prediction accuracy and better generalization performance when measuring the ammonia nitrogen concentration in intensive aquaculture water. It had certain guiding significance for the monitoring of aquaculture water bodies.

soft sensing; ensemble learning; stochastic configuration network; ammonia nitrogen concentration;water quality monitoring

李 康,王 魏,王奕鹏. 集成随机配置网络在养殖水质监测中的应用[J]. 农业工程学报,2020,36(4):220-226. doi:10.11975/j.issn.1002-6819.2020.04.026 http://www.tcsae.org

Li Kang, Wang Wei, Wang Yipeng. Application of ensemble stochastic configuration network in aquaculture water quality monitoring[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2020, 36(4): 220-226. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2020.04.026 http://www.tcsae.org

2019-11-26

2020-01-15

国家自然科学基金(61503054);大连市科技之星项目(2017RQ143);辽宁省教育厅青年科技人才“育苗”项目(QL201912)

李 康,从事水质参数软测量的研究。Email:1564028632@qq.com

王 魏,副教授,博士,从事复杂工业过程建模的研究。Email:ww_wangwei@dlou.edu.cn

10.11975/j.issn.1002-6819.2020.04.026

TP18

A

1002-6819(2020)-04-0220-07

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