Combination of Multivariate Standard Addition Technique and Deep Kernel Learning Model for Determining Multi-Ion in Hydroponic Nutrient Solution
Abstract
:1. Introduction
2. Materials and Methods
2.1. Experiment Preparation
2.1.1. Sensor Array and Apparatus
2.1.2. Sampling Preparation
2.2. Development of Models for Determining Multi-Ion
2.2.1. Neural Network Model
2.2.2. Gaussian Process Model
2.2.3. Deep Kernel Learning Model
2.2.4. Model Performance Metrics
3. Results
3.1. Responses of the Ion Selective Electrodes
3.2. Determination of the DKL Architecture
3.3. Evaluation of the Performance of Proposed Models
3.4. Validation of the Proposed Models with Real Hydroponic Samples
4. Discussion
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sensor | Measurement Range | Membrane Type | Response Time (s) | Manufacturer |
---|---|---|---|---|
Nitrate ISE: REX972123 | 0.6–60000 | PVC | ~50 | Shanghai INESA, China |
Ammonium ISE: REX 972,122 | 0.02–14000 | PVC | ~50 | Shanghai INESA, China |
Potassium ISE: Orion 9719BNWP | 0.04–39000 | PVC | ~50 | Thermo Fisher, USA |
Calcium ISE: Orion 9720BNWP | 0.02–40000 | PVC | ~50 | Thermo Fisher, USA |
Sodium ISE: pNa 701 | 0.03–23000 | Glass | ~50 | Shanghai INESA, China |
Chloride ISE: pCl 202 | 0.35–3500 | PVC | ~50 | Shanghai INESA, China |
pH electrode: E-201F | 2–14 | - | ~50 | Shanghai INESA, China |
EC electrode: DJS-1C | 0–10000 | - | - | Shanghai INESA, China |
Temperature probe: Pt100 | 0–100 | - | - | Yuace, China |
Ions | Level 1 | Level 2 | Level 3 | Level 4 | Level 5 | Level 6 | Level 7 | Level 8 | Level 9 | Level 10 |
---|---|---|---|---|---|---|---|---|---|---|
Nitrate () | 44 | 88 | 177 | 221 | 332 | 442 | 553 | 769 | 1106 | 1328 |
Ammonium () | 6 | 10 | 15 | 20 | 25 | 35 | 45 | 55 | 75 | 120 |
Potassium () | 15 | 50 | 75 | 100 | 150 | 175 | 200 | 225 | 350 | 500 |
Calcium () | 10 | 25 | 50 | 75 | 100 | 125 | 175 | 225 | 250 | 350 |
Sodium () | 5 | 12 | 25 | 35 | 50 | 100 | 150 | 175 | 250 | 300 |
Chloride () | 5 | 15 | 35 | 50 | 80 | 125 | 175 | 200 | 300 | 350 |
Sample | Grown Plant | Growing Period | Nutrient Standard | Sampling Sites |
---|---|---|---|---|
S1 | Lettuce 1 | Three weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S2 | Perilla | Five weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S3 | Lettuce 2 | Four weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S4 | Purple bok choy | Five weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S5 | Chinese cabbage | Six weeks | Yamazaki’s solution | Experimental Plant Factory, CIEE, CAU |
S6 | Strawberry | Eight weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S7 | Gynura bicolor DC | Five weeks | Hoagland’s solution | Experimental Plant Factory, CIEE, CAU |
S8 | Amaranth | Four weeks | Yamazaki’s solution | Experimental farm, CIEE, CAU |
S9 | Eggplant | Twelve weeks | Yamazaki’s solution | Experimental farm, CIEE, CAU |
S10 | Tomato | Six weeks | Yamazaki’s solution | Experimental farm, CIEE, CAU |
Parameters | Values |
Number of hidden layers | 1, 2, 3, 4, 5, 6 |
Hidden layer size | 1 to 1000 |
Hidden layer transfer function f(x) | tansig, logsig, linear, ReLU |
Output layer transfer function | ReLU |
Optimization algorithm | Stochastic gradient descent (SGD), Broyden–Fletcher–Goldfarb–Shanno (BFGS), Adam |
Dropout rate | 0.5 to 0.99 |
Learning rate | 0.001 to 0.1 |
Max number of epochs | 1000 |
Prior whitenoise level | 0.001 to 1 |
Kernel | Radial basic function (RBF), Dotproduct, Spectral mixture (SM) |
Training goal | 10−6 |
ISEs | DCM | MSAM | ||
---|---|---|---|---|
Calibrating Equation | Calibrating Equation | |||
Nitrate | 0.93 | y = −22.04ln(x) + 202.62 | 0.95 | y = −22.86ln(x) + 208.47 |
Ammonium | 0.90 | y = 22.856ln(x) − 255.01 | 0.92 | y = 22.92ln(x) − 253.87 |
Potassium | 0.95 | y = 23.39ln(x) − 240.07 | 0.97 | y = 23.07ln(x) − 237.03 |
Calcium | 0.94 | y = 11.419ln(x) − 79.31 | 0.96 | y = 11.06ln(x) − 76.90 |
Sodium | 0.91 | y = 18.227ln(x) − 178.31 | 0.93 | y = 19.76ln(x) − 186.22 |
Chloride | 0.94 | y = −23.28ln(x) + 186.54 | 0.96 | y = −23.02ln(x) + 192.33 |
Layer 1 | Layer 2 | Layer 3 | Layer 4 | Layer 5 | Opt | LR | N.o.E | KF | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
N.o.N | AF | DR | N.o.N | AF | DR | N.o.N | AF | DR | N.o.N | AF | DR | N.o.N | AF | DR | Adam | 0.005 | 250 | RBF |
580 | Tanh | 0.99 | 580 | Tanh | 0.99 | 100 | ReLU | 0.99 | 100 | ReLU | 0.99 | 8 | ReLU | 0.99 |
Species | Models | Predicting Equation | RMSE | Coefficient of Performance () |
---|---|---|---|---|
Nitrate | ANN | y = 0.95x + 18.11 | 91.5 | 0.95 |
GP | y = 0.94x − 10.93 | 102.7 | 0.94 | |
DKL | y = 1.01x + 17.81 | 58.5 | 0.98 | |
Ammonium | ANN | y = 0.92x + 4.54 | 10.9 | 0.92 |
GP | y = 0.90x + 3.80 | 13.1 | 0.90 | |
DKL | y = 0.95x + 5.13 | 7.4 | 0.95 | |
Potassium | ANN | y = 0.94x + 7.33 | 33.5 | 0.95 |
GP | y = 0.95x + 11.50 | 31.2 | 0.96 | |
DKL | y = 0.99x + 5.59 | 25.2 | 0.978 | |
Calcium | ANN | y = 0.98x + 4.20 | 23.6 | 0.96 |
GP | y = 0.85x + 22.30 | 35.3 | 0.92 | |
DKL | y = 0.99x + 5.27 | 18.8 | 0.97 | |
Sodium | ANN | y = 0.94x − 1.97 | 22.5 | 0.94 |
GP | y = 0.86x + 14.11 | 29.3 | 0.92 | |
DKL | y = 0.97x + 1.08 | 18.9 | 0.96 | |
Chloride | ANN | y = 0.97x + 1.22 | 25.0 | 0.95 |
GP | y = 0.95x + 5.67 | 27.2 | 0.94 | |
DKL | y = 0.99x + 2.68 | 20.3 | 0.97 | |
Phosphate | ANN | y = 0.71x + 31.59 | 122.5 | 0.76 |
GP | y = 0.62x + 20.27 | 135.8 | 0.61 | |
DKL | y = 0.85x + 17.82 | 76.2 | 0.86 | |
Magnesium | ANN | y = 0.82x + 11.43 | 21.3 | 0.75 |
GP | y = 0.63x + 10.64 | 25.2 | 0.62 | |
DKL | y = 0.88x + 2.11 | 13.1 | 0.89 |
Considered Ions | Range of Concentration ) | Models | Accuracy (RMSE, ) | Precision (CV, %) |
---|---|---|---|---|
Nitrate | 150–1150 | ANN | 83.8 | 7.2 |
GP | 86.1 | 8.4 | ||
DKL | 63.8 | 3.5 | ||
Ammonium | 6–120 | ANN | 10.3 | 9.2 |
GP | 12.2 | 10.3 | ||
DKL | 8.3 | 7.0 | ||
Potassium | 15–500 | ANN | 36.3 | 9.2 |
GP | 35.2 | 8.8 | ||
DKL | 29.2 | 5.4 | ||
Calcium | 10–305 | ANN | 25.2 | 7.7 |
GP | 29.1 | 9.6 | ||
DKL | 18.5 | 5.5 | ||
Sodium | 6–175 | ANN | 14.8 | 9.2 |
GP | 17.1 | 9.9 | ||
DKL | 11.8 | 6.8 | ||
Chloride | 1.6–128 | ANN | 11.7 | 9.5 |
GP | 12.8 | 10.5 | ||
DKL | 8.8 | 6.9 | ||
Phosphate | 5–275 | ANN | 50.5 | 22.3 |
GP | 55.8 | 23.6 | ||
DKL | 29.6 | 13.9 | ||
Magnesium | 10–80 | ANN | 16.9 | 21.3 |
GP | 18.1 | 23.5 | ||
DKL | 8.7 | 14.8 |
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Tuan, V.N.; Khattak, A.M.; Zhu, H.; Gao, W.; Wang, M. Combination of Multivariate Standard Addition Technique and Deep Kernel Learning Model for Determining Multi-Ion in Hydroponic Nutrient Solution. Sensors 2020, 20, 5314. https://doi.org/10.3390/s20185314
Tuan VN, Khattak AM, Zhu H, Gao W, Wang M. Combination of Multivariate Standard Addition Technique and Deep Kernel Learning Model for Determining Multi-Ion in Hydroponic Nutrient Solution. Sensors. 2020; 20(18):5314. https://doi.org/10.3390/s20185314
Chicago/Turabian StyleTuan, Vu Ngoc, Abdul Mateen Khattak, Hui Zhu, Wanlin Gao, and Minjuan Wang. 2020. "Combination of Multivariate Standard Addition Technique and Deep Kernel Learning Model for Determining Multi-Ion in Hydroponic Nutrient Solution" Sensors 20, no. 18: 5314. https://doi.org/10.3390/s20185314
APA StyleTuan, V. N., Khattak, A. M., Zhu, H., Gao, W., & Wang, M. (2020). Combination of Multivariate Standard Addition Technique and Deep Kernel Learning Model for Determining Multi-Ion in Hydroponic Nutrient Solution. Sensors, 20(18), 5314. https://doi.org/10.3390/s20185314