Flexible Multimodal Sensors Enhanced by Electrospun Lead-Free Perovskite and PVDF-HFP Composite Form-Stable Mesh Membranes for In Situ Plant Monitoring.

The pH and humidity of the crop environment are essential indicators for monitoring crop growth status. This study reports a lead-free perovskite/polyvinylidene fluoride-hexafluoropropylene composite (LPPC) to enhance the stability and reliability of in situ plant pH and humidity monitoring. The mesh composite membrane of LPPC illustrates a hydrophobic contact angle of 101.

Banana Pseudostem Width Detection Based on Kinect V2 Depth Sensor.

This study used Kinect V2 sensor to collect the three-dimensional point cloud data of banana pseudostem and developed an automatic measurement method of banana pseudostem width. The banana plant was selected as the research object in a banana plantation in Fusui, Guangxi. The mobile measurement of banana pseudostem was carried out at a distance of 1 m from the banana plant using the field operation platform with Kinect V2 as the collection equipment.

Detection of chlorophyll fluorescence parameters of potato leaves based on continuous wavelet transform and spectral analysis.

The tuber development and nutrient transportation of potato crops are closely related to canopy photosynthesis dynamics. Chlorophyll fluorescence parameters of photosystem II, especially the maximum quantum yield of primary photochemistry (Fv/Fm), are intrinsic indicators for plant photosynthesis. Rapid detection of Fv/Fm of leaves by spectroscopy method instead of time-consuming pulse amplitude modulation technique could help to indicate potato development dynamics and guide field management.

Development and Application of a Vehicle-Mounted Soil Texture Detector.

It is of great significance to obtain soil texture information quickly for the realization of farmland management. Soil with good particle condition can well regulate the needs of plants for water, nutrients, air, and temperature during crop growth, thereby promoting high crop yields. The existing methods of measuring soil texture cannot meet the requirements of time and spatial resolution.

Comparison of Soil Total Nitrogen Content Prediction Models Based on Vis-NIR Spectroscopy.

Visible-near-infrared spectrum (Vis-NIR) spectroscopy technology is one of the most important methods for non-destructive and rapid detection of soil total nitrogen (STN) content. In order to find a practical way to build STN content prediction model, three conventional machine learning methods and one deep learning approach are investigated and their predictive performances are compared and analyzed by using a public dataset called LUCAS Soil (19,019 samples). The three conventional machine learning methods include ordinary least square estimation (OLSE), random forest (RF), and extreme learning machine (ELM), while for the deep learning method, three different structures of convolutional neural network (CNN) incorporated Inception module are constructed and investigated.

Growth Stages Classification of Potato Crop Based on Analysis of Spectral Response and Variables Optimization.

Potato is the world's fourth-largest food crop, following rice, wheat, and maize. Unlike other crops, it is a typical root crop with a special growth cycle pattern and underground tubers, which makes it harder to track the progress of potatoes and to provide automated crop management. The classification of growth stages has great significance for right time management in the potato field.

Optimal fertigation for high yield and fruit quality of greenhouse strawberry.

Nitrogen (N), phosphorus (P), potassium (K), and water are four crucial factors that have significant effects on strawberry yield and fruit quality. We used a 11 that involved 36 treatments with five levels of each of the four variables (N, P, and K fertilizers and water) to optimize fertilization and water combination for high yield and quality. Moreover, we used the SSC/TA ratio (the ratio of soluble solid content to titratable acid) as index of quality.

Improving In-Situ Estimation of Soil Profile Properties Using a Multi-Sensor Probe.

Optical diffuse reflectance spectroscopy (DRS) has been used for estimating soil physical and chemical properties in the laboratory. In-situ DRS measurements offer the potential for rapid, reliable, non-destructive, and low cost measurement of soil properties in the field. In this study, conducted on two central Missouri fields in 2016, a commercial soil profile instrument, the Veris P4000, acquired visible and near-infrared (VNIR) spectra (343⁻2222 nm), apparent electrical conductivity (EC), cone index (CI) penetrometer readings, and depth data, simultaneously to a 1 m depth using a vertical probe.

[Rapid Detection of Trace Dimethoate Pesticide Residues Based on Colorimetric Spectroscopy].

In order to detect dimethoate pesticide residues rapidly and safely, a feasible method based on colorimetric spectroscopy was developed. Because dimethoate is one of organophosphorus pesticides containing sulfur, its sulfenyl can react with Pd2+ to produce a yellow complex named palladium sulfide. PdCl2 was used as the color agent, which was dissolved in acetic acid instead of the common concentrated hydrochloric acid.

[Research on maize multispectral image accurate segmentation and chlorophyll index estimation].

In order to rapidly acquire maize growing information in the field, a non-destructive method of maize chlorophyll content index measurement was conducted based on multi-spectral imaging technique and imaging processing technology. The experiment was conducted at Yangling in Shaanxi province of China and the crop was Zheng-dan 958 planted in about 1 000 m X 600 m experiment field. Firstly, a 2-CCD multi-spectral image monitoring system was available to acquire the canopy images.

[A novel vegetation index (MPRI) of corn canopy by vehicle-borne dynamic prediction].

Ground-based remote sensing system is a significant way to understand the growth of corn and provide accurate and scientific data for precision agriculture. The vehicle-borne system is one of the most important tools for corn canopy monitoring. However, the vehicle-borne growth monitoring system cannot maintain steady operations due to the row spacing of corn.

[Visible-NIR spectral feature of citrus greening disease].

Citrus greening (Huanglongbing, or HLB) is a devastating disease caused by Candidatus liberibacter which uses psyllids as vectors. It has no cure till now, and poses a huge threat to citrus industry around the world. In order to diagnose, assess and further control this disease, it is of great importance to first find a quick and effective way to detect it.

[Detection of chlorophyll content in water body based on two-dimensional correlation spectroscopy].

Twenty five samples were collected from 10 different ponds in Jiangsu Province of China. According to the different water status and surface area of each pond, different numbers of water samples were collected. The present paper aims to detect chlorophyll content in water body based on hyperspectrum.

[Grey analysis of NIR spectra and prediction of nitrogen content in jujube leaves].

Jujube was chosen as the object in the present research. Spectra data of jujube leaves were collected during the period of budding, branch leaf, flowering and coloring. The nitrogen contents of jujube leaf samples were determined by Kjeldahl analysis method.

[Detection of onion soluble solids content based on the near-infrared reflectance spectra].

Onion soluble solids content (SSC) was detected using near-infrared (924-1720 nm) reflectance spectra. Three cultivars of onions, harvested at different period, were selected for experiment and the total number of samples is 268. SSC reference value of onion juice was determined using the temperature compensated refractometer.

[Effect of soil moisture on prediction of soil total nitrogen using NIR spectroscopy].

As one of the most important components of soil liutrient, it is necessary to obtain the soil total nitrogen(STN)content in precision agriculture. It is a feasible method to predict soil total nitrogen content based on NIRS. However, the effect of soil moisture content (SMC) on the prediction of STN is very serious.

[Prediction of chlorophyll content of greenhouse tomato using wavelet transform combined with NIR spectra].

In quantitative analysis of spectral data, noises and background interference always degrade the accuracy of spectral feature extraction. The wavelet transform is multi-scale decomposition used to reduce the noise and improve the analysis precision. On the other hand, the wavelet transform denoising is often followed by destroying the efficiency information.

[The canopy and leaf spectral characteristics and nutrition diagnosis of tomato in greenhouse].

A green house experiment was conducted to research the characteristics of tomato canopy spectral reflectance and leaf spectral reflectance under different nutrition treatments, and the relationships between spectral reflectance and the water content, chlorophyll content, as well as nitrogen content were analyzed. Substrate cultivation method was used to grow the plants. The substrate was made from a mixture of peat and vermiculite.

[Development of a portable SOM detector based on NIR diffuse reflection].

A portable soil organic matter detector based on near infrared diffuse reflectance was developed. The detector uses a microprocessor 89S52 as the micro controller unit (MCU) and consists of an optical system and a control system. The optical system includes an 850 nm near-infrared LED lamp-house, a lamp-house driving-circuit, a Y type optical fiber, a probe, and a photoelectric sensor.

[Monitoring of Cnaphalocrocis medinalis Guenee based on canopy reflectance].

The canopy reflectance of rice was measured in the filed in order to monitor the damaged region caused by Cnaphalocrocis medinalis Guenee. The characteristics of canopy spectral reflectance were analyzed in contrast region and damaged regions. When rice plant was damaged by Cnaphalocrocis medinalis Guenee, the chlorophyll absorption was decreased in the band of 600-700 nm.

[Spectral characteristics of corn under different nitrogen treatments].

The canopy spectral reflectance and chlorophyll content of corn were measured and analyzed under different nitrogen treatments. The trends of chlorophyll content were discussed based on different growth stages and different nitrogen levels. It was observed that the chlorophyll content increased with the increase in nitrogen, and could be affected by the environment changes including the temperature, rain, fertilizer treatment and so on.

[Nitrogen content testing and diagnosing of cucumber leaves based on multispectral imagines].

Using CCD camera and special filters, the growth parameters of cucumber plants, the nitrogen content and the area of leaves, were investigated in an experimental greenhouse. In order to make nutrient stress to the plants, different nitrogen levels were prepared. The basic nitrogen content was 0.

[Characteristics of soil spectral reflectance and estimation of soil parameters in Fuxin opencast coal mine].

The surface soil samples of Fuxin opencast coal overburden dumps were collected in the field and the spectral reflectance and characteristic parameters of the soil samples, such as moisture content, pH, electrical conductivity (EC), available potassium (K+) content, and soil organic matter content (SOM), were measured. The Analysis results indicated that the curves of the soil spectral reflectance decreased with increasing the laid years. The possible reasons were the influences of soil texture and color.