CN116151121B - Neural network-based effluent NH4-N soft measurement method - Google Patents

Neural network-based effluent NH4-N soft measurement method Download PDF

Info

Publication number
CN116151121B
CN116151121B CN202310181946.1A CN202310181946A CN116151121B CN 116151121 B CN116151121 B CN 116151121B CN 202310181946 A CN202310181946 A CN 202310181946A CN 116151121 B CN116151121 B CN 116151121B
Authority
CN
China
Prior art keywords
network
sub
echo state
weight
constructing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202310181946.1A
Other languages
Chinese (zh)
Other versions
CN116151121A (en
Inventor
杨翠丽
乔俊飞
王明星
刘阳
王明
顾明珠
白冉
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Beijing University of Technology
Original Assignee
Beijing University of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Beijing University of Technology filed Critical Beijing University of Technology
Priority to CN202310181946.1A priority Critical patent/CN116151121B/en
Publication of CN116151121A publication Critical patent/CN116151121A/en
Application granted granted Critical
Publication of CN116151121B publication Critical patent/CN116151121B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/20Design optimisation, verification or simulation
    • G06F30/27Design optimisation, verification or simulation using machine learning, e.g. artificial intelligence, neural networks, support vector machines [SVM] or training a model
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06NCOMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
    • G06N3/00Computing arrangements based on biological models
    • G06N3/02Neural networks
    • G06N3/08Learning methods
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16CCOMPUTATIONAL CHEMISTRY; CHEMOINFORMATICS; COMPUTATIONAL MATERIALS SCIENCE
    • G16C20/00Chemoinformatics, i.e. ICT specially adapted for the handling of physicochemical or structural data of chemical particles, elements, compounds or mixtures
    • G16C20/20Identification of molecular entities, parts thereof or of chemical compositions
    • GPHYSICS
    • G16INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16CCOMPUTATIONAL CHEMISTRY; CHEMOINFORMATICS; COMPUTATIONAL MATERIALS SCIENCE
    • G16C20/00Chemoinformatics, i.e. ICT specially adapted for the handling of physicochemical or structural data of chemical particles, elements, compounds or mixtures
    • G16C20/70Machine learning, data mining or chemometrics

Landscapes

  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Evolutionary Computation (AREA)
  • Computing Systems (AREA)
  • Artificial Intelligence (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Software Systems (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Bioinformatics & Computational Biology (AREA)
  • Health & Medical Sciences (AREA)
  • Medical Informatics (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Chemical & Material Sciences (AREA)
  • Data Mining & Analysis (AREA)
  • General Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Molecular Biology (AREA)
  • Mathematical Physics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Computational Linguistics (AREA)
  • Biophysics (AREA)
  • Geometry (AREA)
  • Computer Hardware Design (AREA)
  • Databases & Information Systems (AREA)
  • Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)

Abstract

The invention provides a neural network-based effluent NH4-N soft measurement method, which comprises the following steps: initializing a network structure and network parameters of the constructed echo state network; constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; optimizing the sub-pool according to the condition number and the differential evolution algorithm; updating the optimized weight, input weight and state matrix of the sub-reserve pool, judging whether the iteration times are smaller than a preset iteration threshold, if so, jumping to the step of constructing the sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight; testing the echo state network according to the output weight and the test sample to obtain a determined effluent NH4-N detection model; and inputting the data to be detected into a determined effluent NH4-N detection model to obtain a detection result. The invention provides a high-efficiency and rapid solution for measuring key water quality parameters in the sewage treatment process.

Description

Neural network-based effluent NH4-N soft measurement method
Technical Field
The invention relates to the technical field of water treatment, in particular to a neural network-based effluent NH4-N soft measurement method.
Background
With the rapid development of urban and industrialized production in the current society, the water environment in China is seriously destroyed. The sewage discharge not only seriously affects the daily life of residents, but also destroys the ecological balance of the nature. In order to reduce the discharge amount of sewage and realize the recycling of the water, sewage treatment plants are established in various places nationwide. In the sewage treatment process, the NH4-N concentration is an important parameter for measuring the performance of a sewage treatment process (WWTP), however, the sewage treatment process is a complex system with the characteristics of high nonlinearity, large hysteresis, large time variation, multivariable coupling and the like, and the maintenance cost is high, so that the prediction of the sewage treatment process is still a pending problem. Therefore, it is necessary to predict the concentration of NH4-N in the effluent at low cost and high efficiency for the quality of the effluent to be checked and for the sewage treatment plant to be stably operated.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a neural network-based effluent NH4-N soft measurement method, and the method can predict the ammonia nitrogen concentration in the sewage treatment process by combining a differential evolution algorithm with condition number analysis to construct a novel echo state network.
In order to achieve the above object, the present invention provides the following solutions:
a neural network-based effluent NH4-N soft measurement method comprises the following steps:
constructing an echo state network, and initializing a network structure and network parameters of the echo state network; the input variables of the echo state network comprise water inlet temperature, total solid suspended matters, dissolved oxygen concentration, pH value and water outlet oxidation-reduction potential; the output variables of the echo state network comprise ammonia nitrogen concentration;
constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
optimizing the sub-pool according to condition numbers and a differential evolution algorithm;
updating the optimized weight, input weight and state matrix of the sub-reserve pool, judging whether the iteration times are smaller than a preset iteration threshold, if so, jumping to the step of constructing the sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight;
testing the echo state network according to the output weight and the sample to be tested to obtain a determined effluent NH4-N detection model;
and inputting the data to be detected into a determined effluent NH4-N detection model to obtain a detection result.
Preferably, initializing a network structure and network parameters of the echo state network includes:
determining the initial structure of the echo state network to be 5-N-1; wherein N represents the number of sub-pool nodes; the size of N is gradually increased;
using a sigmoid function as a network activation function G (·), determining an initial iteration number i=1 and a maximum iteration number i max Training samples less than or equal to 30Wherein u is k Represents the k-th set of input samples, t k Represents the k-th set of actual output values, +.>Representing the dimension of the input samples as n, and L as the total number of samples;
randomly initializing network input weight W in And the pool internal weight W is between (0, 1).
Preferably, the constructing the sub-pool according to the singular value decomposition method based on the initialized echo state network includes:
randomly generating a diagonal matrixTwo orthogonal matrices U i And V i The method comprises the steps of carrying out a first treatment on the surface of the Wherein,for randomly generated values between (0, 1), n k The number of nodes of the sub reserve pool;
constructing sub-reserves Chi W using the diagonal matrix and two of the orthogonal matrices i =U i S i V i
Preferably, said optimizing said sub-pool according to condition number and differential evolution algorithm comprises:
construction of fitness function fitness (ΔW i )=κ(H i )-κ(H i-1 ) The method comprises the steps of carrying out a first treatment on the surface of the Wherein, kappa (H) i ) Representing the condition number of the state matrix corresponding to the pool after the new sub-pool is added;
initializing an initial population np=50, mutating operator f=0.7, crossing operator cr=0.5, and initializing the populationWherein n is {1,2 …, NP }, and a maximum iteration number G is set;
according to the formulaObtaining variant individual mu n The method comprises the steps of carrying out a first treatment on the surface of the Wherein r is 1 ,r 2 ,r 3 ∈[1,NP]Are three mutually different integers;
by passing throughFinishing the crossover operation for each individual +.>Obtaining cross subject->Wherein j e {1,2 …,10}, rand e (0, 1) is randomly generated;
and after the algorithm reaches the maximum iteration times, terminating the algorithm flow, returning to the optimal individual, and constructing a new sub-storage pool by using the optimal individual.
Preferably, the optimized weight, input weight and state matrix of the sub-reservoir are updated, and whether the iteration number is smaller than a preset iteration threshold is judged, if yes, the step is skipped to the step of constructing the sub-reservoir according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight, including:
updating the weight of the reserve pool to be
Updating the input weight to
Updating the state matrix to h= [ H ] 1 ,…,H i ];
If i is more than or equal to i max Executing the next step, otherwise returning to the step of constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
by the formula W out =H Γ T calculates the output weight W out The method comprises the steps of carrying out a first treatment on the surface of the Wherein Γ represents pseudo-inverse computation, and T is target output data.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects:
the invention provides a neural network-based effluent NH4-N soft measurement method, which comprises the following steps: constructing an echo state network, and initializing a network structure and network parameters of the echo state network; the input variables of the echo state network comprise water inlet temperature, total solid suspended matters, dissolved oxygen concentration, pH value and water outlet oxidation-reduction potential; the output variables of the echo state network comprise ammonia nitrogen concentration; constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; optimizing the sub-pool according to condition numbers and a differential evolution algorithm; updating the optimized weight, input weight and state matrix of the sub-reserve pool, judging whether the iteration times are smaller than a preset iteration threshold, if so, jumping to the step of constructing the sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight; testing the echo state network according to the output weight and the sample to be tested to obtain a determined effluent NH4-N detection model; and inputting the data to be detected into a determined effluent NH4-N detection model to obtain a detection result. The invention provides a high-efficiency and rapid solution for measuring key water quality parameters in the sewage treatment process.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a method according to an embodiment of the present invention;
fig. 2 is a topology structure diagram of a neural network according to an embodiment of the present invention;
FIG. 3 is a graph showing the absolute value distribution of output weights according to an embodiment of the present invention;
FIG. 4 is a graph of the predicted NH4-N concentration result of the effluent provided by the embodiment of the invention;
FIG. 5 is a chart of the prediction error of the NH4-N concentration of the effluent provided by the embodiment of the invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.
The terms "first," "second," "third," and "fourth" and the like in the description and in the claims of this application and in the drawings, are used for distinguishing between different objects and not for describing a particular sequential order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, inclusion of a list of steps, processes, methods, etc. is not limited to the listed steps but may alternatively include steps not listed or may alternatively include other steps inherent to such processes, methods, products, or apparatus.
The invention aims to provide a neural network-based effluent NH4-N soft measurement method, which can provide a high-efficiency and rapid solution for measuring key water quality parameters in the sewage treatment process.
In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.
Fig. 1 is a flowchart of a method provided by an embodiment of the present invention, and as shown in fig. 1, the present invention provides a method for soft measurement of NH4-N in effluent based on a neural network, including:
step 100: constructing an echo state network, and initializing a network structure and network parameters of the echo state network; the input variables of the echo state network comprise water inlet temperature, total solid suspended matters, dissolved oxygen concentration, pH value and water outlet oxidation-reduction potential; the output variables of the echo state network comprise ammonia nitrogen concentration;
step 200: constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
step 300: optimizing the sub-pool according to condition numbers and a differential evolution algorithm;
step 400: updating the optimized weight, input weight and state matrix of the sub-reserve pool, judging whether the iteration times are smaller than a preset iteration threshold, if so, jumping to the step of constructing the sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight;
step 500: testing the echo state network according to the output weight and the sample to be tested to obtain a determined effluent NH4-N detection model;
step 600: and inputting the data to be detected into a determined effluent NH4-N detection model to obtain a detection result.
Preferably, initializing a network structure and network parameters of the echo state network includes:
determining the initial structure of the echo state network to be 5-N-1; wherein N represents the number of sub-pool nodes; the size of N is gradually increased;
using a sigmoid function as a network activation function G (·), determining an initial iteration number i=1 and a maximum iteration number i max Training samples less than or equal to 30Wherein u is k Represents the k-th set of input samples, t k Represents the k-th set of actual output values, +.>Representing the dimension of the input samples as n, and L as the total number of samples;
randomly initializing network input weight W in And the pool internal weight W is between (0, 1).
Specifically, in the method for soft measurement of effluent NH4-N based on the CNEESN neural network in this embodiment, the network is a continuously growing network, and the main operation flow is as follows: firstly, a small-scale reserve pool is generated, corresponding weights are initialized, singular values randomly generated by a Singular Value Decomposition (SVD) method are optimized and utilized according to condition number analysis and differential evolution algorithm, a new sub-reserve pool is built by utilizing the optimized singular values, and then the new sub-reserve pool is added into a network, as shown in figure 2. In the embodiment, after each sub-reserve tank is added into the network by using condition number analysis and differential evolution algorithm, the condition number of the reserve tank of the network is as small as possible, so that a better output weight is obtained through training, and then the ammonia nitrogen concentration in the sewage treatment process is predicted. The embodiment comprises the following steps:
step 1: initializing network structure and parameters
Step 1.1: initializing a network structure
And taking the water inlet temperature, the total solid suspended matters, the dissolved oxygen concentration, the pH value and the oxidation-reduction potential of the water outlet as input variables, and the ammonia nitrogen concentration as output variables, and determining the initial structure of the echo state network to be 5-N-1, wherein N represents the number of nodes of the sub-reserve pool. The number N of the pool nodes of the typical echo state network is equal to or more than 50 and equal to or less than 1000, but the model proposed by the method is a growth model, and the size of N is gradually increased. The initial N in the network takes 10, namely the network contains 5 input nodes, 10 reserve pool nodes and 1 output node.
Step 1.2: initializing network parameters
Using a sigmoid function as a network activation function G (·), determining an initial iteration number i=1 and a maximum iteration number i max Training samples less than or equal to 30u k Represents the k-th set of input samples, t k Represents the k-th set of actual output values, +.>Representing the dimension of the input samples as n, and L as the total number of samples; randomly initializing network input weight W in And the pool internal weight W is between (0, 1).
Preferably, the constructing the sub-pool according to the singular value decomposition method based on the initialized echo state network includes:
randomly generating a diagonal matrixTwo orthogonal matrices U i And V i The method comprises the steps of carrying out a first treatment on the surface of the Wherein,for randomly generated values between (0, 1), n k The number of nodes of the sub reserve pool;
constructing sub-reserves Chi W using the diagonal matrix and two of the orthogonal matrices i =U i S i V i
Alternatively, step 2 of the present embodiment is to construct sub-reservoirs from singular value decomposition. The present embodiment randomly generates a diagonal matrixTwo orthogonal matrices U i And V i Using three matrices, a sub-store Chi W can be constructed i =U i S i V i . By this means ΔW can be ensured i And S is i With the same singular values, thus guaranteeing ESP characteristics.
Preferably, said optimizing said sub-pool according to condition number and differential evolution algorithm comprises:
construction of fitness function fitness (ΔW i )=κ(H i )-κ(H i-1 ) The method comprises the steps of carrying out a first treatment on the surface of the Wherein, kappa (H) i ) Representing the condition number of the state matrix corresponding to the pool after the new sub-pool is added;
initializing an initial population np=50, mutating operator f=0.7, crossing operator cr=0.5, and initializing the populationWherein n is {1,2 …, NP }, and a maximum iteration number G is set;
according to the formulaObtaining variant individual mu n The method comprises the steps of carrying out a first treatment on the surface of the Wherein r is 1 ,r 2 ,r 3 ∈[1,NP]Are three mutually different integers;
by passing throughFinishing the crossover operation for each individual +.>Obtaining cross subject->Wherein j e {1,2 …,10}, rand e (0, 1) is randomly generated;
and after the algorithm reaches the maximum iteration times, terminating the algorithm flow, returning to the optimal individual, and constructing a new sub-storage pool by using the optimal individual.
Specifically, step 3 in this embodiment is to optimize the sub-pool according to the condition number and the differential evolution algorithm, and specifically includes the following steps:
step 3.1: the design fitness function is based on the theoretical analysis of the condition number of the matrix, and it is known that the larger the condition number is, the more easily the problem of pathological solution is generated when the operation of the matrix is performed. The present embodiment therefore designs a fitness function to measure the performance of the newly created sub-reservoirs. The specific calculation mode is as follows:
fitness(ΔW i )=κ(H i )-κ(H i-1 ) (1)
wherein kappa (H) i ) Representing the condition number of the state matrix corresponding to the pool after the addition of the new sub-pool.
Step 3.2: optimizing SVD generated singular values using differential evolutionary algorithm
Initial population np=50, mutation operator f=0.7, crossover operator cr=0.5. Initializing a populationWhere n ε {1,2 …, NP } and set the maximum number of iterations G.
Obtaining variant individuals through a formula (2)μ n
Wherein r is 1 ,r 2 ,r 3 ∈[1,NP]Are three mutually different integers.
Performing a crossover operation by equation (3), σ for each individual j n gives the crossover individual gamma j n
Where j ε {1,2 …,10}, rand ε (0, 1) is randomly generated.
The selection operation is completed by the formula (4)
fitness (·) represents fitness function calculation in equation (1).
And after the algorithm reaches the maximum iteration times, terminating the algorithm flow, and returning to the optimal individual. The individual is used to construct a new sub-pool.
Preferably, the optimized weight, input weight and state matrix of the sub-reservoir are updated, and whether the iteration number is smaller than a preset iteration threshold is judged, if yes, the step is skipped to the step of constructing the sub-reservoir according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight, including:
updating the weight of the reserve pool to be
Updating the input weight to
Updating the state matrix to h= [ H ] 1 ,…,H i ];
If i is more than or equal to i max Executing the next step, otherwise returning to the step of constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
by the formula W out =H Γ T calculates the output weight W out The method comprises the steps of carrying out a first treatment on the surface of the Wherein Γ represents pseudo-inverse computation, and T is target output data.
Further, step 4 in this embodiment is to update the structure and parameters of the network. The embodiment updates the weight of the reserve pool asThe input weight is updated to->The state matrix is updated to h= [ H ] 1 ,…,H i ]。
If i is more than or equal to i max Step 5 is executed, otherwise step 2 is returned.
Further, as shown in fig. 3, step 5 in this embodiment: and calculating an output weight. The output weight can be calculated by equation (5):
W out =H Γ T(5)
where Γ represents the pseudo-inverse, and T is the target output data.
In addition, step 6 of the present embodiment is a test network, and the output weight W obtained by the above steps is used out And inputting a test sample to test the network. In this example, the tested network was applied to the prediction of NH4-N concentration in the effluent, and the results and errors are shown in FIGS. 4 and 5, respectively.
The data samples in this example are shown below, with tables 1-12 being experimental data for the present invention. Tables 1-5 are training input samples: the water inlet temperature, the aerobic end dissolved oxygen, the total solid suspended matters at the aerobic end, the pH value of the water outlet and the oxidation-reduction potential of the water outlet are shown in a table 6, the concentration of ammonia nitrogen in the water outlet of a training sample, and tables 7-11 are test input samples: the water inlet temperature, the aerobic end dissolved oxygen, the total solid suspended matters at the aerobic end, the pH value of the effluent, the oxidation-reduction potential of the effluent, and the concentration of ammonia nitrogen in the effluent of the test sample are shown in Table 12.
TABLE 1 auxiliary variable inlet Water temperature (. Degree.C.)
TABLE 2 auxiliary variable dissolved oxygen (mg/L)
TABLE 3 auxiliary variable total solids suspension (mg/L)
/>
TABLE 4 auxiliary variable pH
/>
TABLE 5 oxidation-reduction potential of auxiliary variables
/>
Table 6 shows the NH4-N concentration (mg/L)
/>
The test samples were as follows:
TABLE 7 auxiliary variable inlet temperature (. Degree. C.)
26.6664 25.5925 26.0751 26.8655 24.9307 24.9436 25.2516 25.8255 24.9177 25.4691
25.6463 23.6239 26.7961 23.3835 25.5664 25.6231 23.6806 24.1833 25.5388 25.7410
25.9991 25.5576 24.9465 24.9725 24.7418 27.2087 25.8663 26.7136 24.9061 25.6696
24.6813 23.2770 23.8631 24.9667 26.8065 24.4801 24.8874 25.4850 22.9625 25.2472
25.9962 27.1094 25.6289 25.4081 24.2291 25.4720 27.2028 25.3994 25.5649 24.6698
24.9018 24.5476 25.3617 23.7378 24.3022 24.9840 22.8098 25.0100 25.2979 25.0303
27.0784 24.2721 24.4198 24.9826 25.6667 23.0559 23.7307 25.4778 25.3893 25.5126
25.6725 25.4067 25.0534 23.1565 25.0881 24.9119 24.9667 24.9480 24.8686 26.9098
25.9305 23.2841 25.3486 25.2993 24.5188 25.4371 24.9480 27.2933 25.9845 25.4618
25.2212 27.0562 23.1027 24.8614 25.0852 24.5591 25.4153 25.6260 26.9349 25.3501
25.3486 24.3796 25.2936 23.6253 24.5404 24.2047 26.7917 24.6051 25.6158 24.6368
22.9115 24.9047 25.2559 26.5046 27.1331 25.9641 24.9999 26.0429 23.6295 24.6698
24.7908 24.7490 26.0283 23.0630 25.4952 25.1589 23.2032 23.5598 25.6522 23.3310
25.5402 23.1551 23.8745 24.6152 26.7858 25.1633 25.9436 23.6295 25.1532 25.8255
24.8052 25.2950 25.1778 23.9902 27.3334 27.1880 23.4745 26.9556 25.3399 23.4048
25.9539 26.8153 25.6740 25.4458 26.0400 25.1315 24.8225 24.9494 23.4318 25.5053
26.6723 26.8212 23.0956 25.4981 25.2299 23.5769 23.6096 23.1381 23.7006 25.5068
23.5114 25.6405 25.1488 23.8717 26.9763 27.2147 26.9526 25.1040 23.6422 25.1285
25.1300 23.8477 23.4190 23.0191 24.9595 24.1218 23.6338 25.2849 23.6295 26.7652
Table 8 auxiliary variable dissolved oxygen (mg/L)
0.0562 0.0366 0.0480 0.0492 0.0497 0.0355 0.0298 0.0680 0.0501 1.4971
0.0307 0.9334 0.0395 0.3574 0.0322 0.0480 1.1828 0.4821 0.0792 0.0507
0.0692 0.0401 4.8300 0.0371 0.0606 0.0518 0.0811 0.0602 0.0542 0.0325
0.0450 0.3821 0.8550 0.0382 0.0559 0.3764 5.7695 1.5715 1.0503 0.0367
0.1061 0.0507 0.0311 0.2692 0.4867 0.0310 0.0581 0.0504 0.0509 0.0501
0.0457 0.3747 0.0375 0.2519 0.4357 0.0396 0.2746 0.0319 0.0336 3.3770
0.0644 0.4701 5.4844 0.0391 0.0305 0.5861 0.2103 0.0344 0.5381 0.3484
0.0391 2.2688 0.0882 0.2611 0.0321 0.0716 0.0659 0.0359 0.0427 0.0656
0.0531 0.3268 0.0311 0.0296 5.3460 0.1882 0.0288 0.0394 0.0860 0.1166
0.0336 0.0735 0.3412 0.0423 0.0567 0.1819 0.0303 0.0308 0.0654 0.0301
0.5169 0.4193 0.0911 0.8742 0.1841 0.4882 0.0972 0.1170 0.0318 0.0765
0.3444 0.0666 0.0340 0.0582 0.0585 0.0609 0.0339 0.0683 0.9117 5.2513
0.0416 0.0291 0.0689 0.2962 0.0333 0.0450 0.2693 0.2476 0.0603 0.3696
0.0374 0.3343 0.5440 0.4043 0.0587 0.0342 0.0633 0.2651 0.0380 0.0793
0.0307 0.0460 0.0352 0.8274 0.0383 0.0382 0.3765 0.0484 0.0438 0.9111
0.0425 0.0411 0.0398 2.0565 0.0398 0.0739 0.0663 0.0301 0.3594 0.4145
0.1327 0.0987 0.2734 1.1829 0.0315 0.4537 0.2459 0.3024 0.5110 1.2652
0.3495 0.0317 0.0395 0.4844 0.0470 0.0514 0.0417 0.0336 1.2551 0.0351
0.0843 0.2665 0.7375 0.7197 0.0962 0.7756 0.2465 0.1265 0.8817 0.0793
TABLE 9 auxiliary variable total solids suspension (mg/L)
TABLE 10 auxiliary variable pH
TABLE 11 oxidation-reduction potential of auxiliary variables
Table 12 shows the NH4-N concentration (mg/L) of water
The beneficial effects of the invention are as follows:
according to the invention, condition number analysis and a differential evolution algorithm are combined to optimize the ESN network structure, so that the problem of pathological solution is avoided, the robustness of the network is improved, and the anti-interference performance of the network is improved.
In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to assist in understanding the methods of the present invention and the core ideas thereof; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.

Claims (2)

1. The water outlet NH4-N soft measurement method based on the neural network is characterized by comprising the following steps of:
constructing an echo state network, and initializing a network structure and network parameters of the echo state network; the input variables of the echo state network comprise water inlet temperature, total solid suspended matters, dissolved oxygen concentration, pH value and water outlet oxidation-reduction potential; the output variables of the echo state network comprise ammonia nitrogen concentration;
constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
optimizing the sub-pool according to condition numbers and a differential evolution algorithm;
updating the optimized weight, input weight and state matrix of the sub-reserve pool, judging whether the iteration times are smaller than a preset iteration threshold, if so, jumping to the step of constructing the sub-reserve pool according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight;
testing the echo state network according to the output weight and the sample to be tested to obtain a determined effluent NH4-N detection model;
inputting data to be detected into a determined effluent NH4-N detection model to obtain a detection result;
initializing the network structure and network parameters of the echo state network, including:
determining the initial structure of the echo state network to be 5-N-1; wherein N represents the number of sub-pool nodes; the size of N is gradually increased;
using a sigmoid function as a network activation function G (·), determining an initial iteration number i=1 and a maximum iteration number i max Training samples less than or equal to 30Wherein u is k Represents the k-th set of input samples, t k Represents the k-th set of actual output values, +.>Representing the dimension of the input samples as n, and L as the total number of samples;
randomly initializing network input weight W in And the weight W inside the reservoir is between (0, 1);
the method for constructing the sub-reserve pool based on the initialized echo state network according to the singular value decomposition method comprises the following steps:
randomly generating a diagonal matrixTwo orthogonal matrices U i And V i The method comprises the steps of carrying out a first treatment on the surface of the Wherein (1)>For randomly generated values between (0, 1), n k The number of nodes of the sub reserve pool;
constructing sub-reserves Chi W using the diagonal matrix and two of the orthogonal matrices i =U i S i V i
The optimizing the sub-pool according to condition numbers and differential evolution algorithms comprises:
construction of fitness function fitness (ΔW i )=κ(H i )-κ(H i-1 ) The method comprises the steps of carrying out a first treatment on the surface of the Wherein, kappa (H) i ) Representing the condition number of the state matrix corresponding to the pool after the new sub-pool is added;
initializing an initial population np=50, mutation operatorF=0.7, crossover operator cr=0.5, and initializing populationWherein n is {1,2 …, NP }, and a maximum iteration number G is set;
according to the formulaObtaining variant individual mu n The method comprises the steps of carrying out a first treatment on the surface of the Wherein r is 1 ,r 2 ,r 3 ∈[1,NP]Are three mutually different integers;
by passing throughFinishing the crossover operation for each individual +.>Obtaining crossed individualsWherein j e {1,2 …,10}, rand e (0, 1) is randomly generated;
and after the algorithm reaches the maximum iteration times, terminating the algorithm flow, returning to the optimal individual, and constructing a new sub-storage pool by using the optimal individual.
2. The neural network-based effluent NH4-N soft measurement method of claim 1, wherein the method updates the optimized weights, input weights, and state matrices of the sub-reservoirs, and determines whether the iteration number is less than a preset iteration threshold, and if so, jumps to the step of constructing a sub-reservoir according to a singular value decomposition method based on the initialized echo state network; if yes, calculating an output weight, including:
updating the weight of the reserve pool to be
Updating the input weight to
Updating the state matrix to h= [ H ] 1 ,...,H i ];
If i is more than or equal to i max Executing the next step, otherwise returning to the step of constructing a sub-reserve pool according to a singular value decomposition method based on the initialized echo state network;
by the formula W out =H Γ T calculates the output weight W out The method comprises the steps of carrying out a first treatment on the surface of the Wherein Γ represents pseudo-inverse computation, and T is target output data.
CN202310181946.1A 2023-02-21 2023-02-21 Neural network-based effluent NH4-N soft measurement method Active CN116151121B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310181946.1A CN116151121B (en) 2023-02-21 2023-02-21 Neural network-based effluent NH4-N soft measurement method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310181946.1A CN116151121B (en) 2023-02-21 2023-02-21 Neural network-based effluent NH4-N soft measurement method

Publications (2)

Publication Number Publication Date
CN116151121A CN116151121A (en) 2023-05-23
CN116151121B true CN116151121B (en) 2024-03-26

Family

ID=86356179

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310181946.1A Active CN116151121B (en) 2023-02-21 2023-02-21 Neural network-based effluent NH4-N soft measurement method

Country Status (1)

Country Link
CN (1) CN116151121B (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104104629A (en) * 2014-05-27 2014-10-15 温州大学 Rapid signal detection method based on echo state network
CN110837886A (en) * 2019-10-28 2020-02-25 北京工业大学 Effluent NH4-N soft measurement method based on ELM-SL0 neural network
CN115660165A (en) * 2022-10-23 2023-01-31 北京工业大学 Modular neural network effluent ammonia nitrogen concentration multi-step prediction method based on double-layer PSO

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104104629A (en) * 2014-05-27 2014-10-15 温州大学 Rapid signal detection method based on echo state network
CN110837886A (en) * 2019-10-28 2020-02-25 北京工业大学 Effluent NH4-N soft measurement method based on ELM-SL0 neural network
CN115660165A (en) * 2022-10-23 2023-01-31 北京工业大学 Modular neural network effluent ammonia nitrogen concentration multi-step prediction method based on double-layer PSO

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
An ammonia nitrogen concentration online soft measure method based on the neural network;Ge Zhao 等;《Proceedings of the 36th Chinese Control Conference》;3994-3999 *
回声状态网络优化设计及应用研究;王磊;《中国博士学位论文全文数据库 信息科技辑》(第3期);I140-16 *
改进K-means算法优化RBF神经网络的出水氨氮预测;乔俊飞 等;《控制工程》;第25卷(第3期);375-379 *

Also Published As

Publication number Publication date
CN116151121A (en) 2023-05-23

Similar Documents

Publication Publication Date Title
US11346831B2 (en) Intelligent detection method for biochemical oxygen demand based on a self-organizing recurrent RBF neural network
US10570024B2 (en) Method for effluent total nitrogen-based on a recurrent self-organizing RBF neural network
CN109408774B (en) Method for predicting sewage effluent index based on random forest and gradient lifting tree
CN102854296B (en) Sewage-disposal soft measurement method on basis of integrated neural network
CN108469507B (en) Effluent BOD soft measurement method based on self-organizing RBF neural network
CN111354423B (en) Method for predicting ammonia nitrogen concentration of effluent of self-organizing recursive fuzzy neural network based on multivariate time series analysis
CN110824915B (en) GA-DBN network-based intelligent monitoring method and system for wastewater treatment
CN109657790A (en) A kind of Recurrent RBF Neural Networks water outlet BOD prediction technique based on PSO
CN112989704A (en) DE algorithm-based IRFM-CMNN effluent BOD concentration prediction method
CN112765902A (en) RBF neural network soft measurement modeling method based on TentFWA-GD and application thereof
CN109978024B (en) Effluent BOD prediction method based on interconnected modular neural network
CN109408896B (en) Multi-element intelligent real-time monitoring method for anaerobic sewage treatment gas production
CN116151121B (en) Neural network-based effluent NH4-N soft measurement method
CN113111576B (en) Mixed coding particle swarm-long-short-term memory neural network-based effluent ammonia nitrogen soft measurement method
CN110705752A (en) Sewage BOD real-time prediction method based on ANFIS and mechanism model
CN110837886A (en) Effluent NH4-N soft measurement method based on ELM-SL0 neural network
CN112000004B (en) Sewage treatment concentration control method utilizing iterative quadratic heuristic programming
CN110991616B (en) Method for predicting BOD of effluent based on pruning feedforward small-world neural network
CN110909492A (en) Sewage treatment process soft measurement method based on extreme gradient lifting algorithm
CN115905821A (en) Urban sewage treatment process state monitoring method based on multi-stage dynamic fuzzy width learning
CN111832873B (en) Pipe diameter determining method and system for water supply pipeline in old urban area
CN111177971B (en) Sludge volume index distributed soft measurement method
CN111815151A (en) Sewage treatment plant methane yield prediction method based on data mining
CN113222324A (en) Sewage quality monitoring method based on PLS-PSO-RBF neural network model
CN113221436B (en) Sewage suspended matter concentration soft measurement method based on improved RBF neural network

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant