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Zheng S.,South China Agricultural University | Wang W.,South China Agricultural University | Wang W.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | Wang W.,Applied Technology Internet | And 3 more authors.
Journal of Networks | Year: 2014

This paper designs a WSN gateway for environmental monitoring of paddy field, which includes the hardware structure and the software program. We use the MSP430F149 as the core of the gateway node and the nRF905 as the peripherals equipment for node communication. We choose TDR-3, a soil moisture sensor, and DHT22, a temperature-humidity sensor, to collect and process the environmental information of the paddy field in real time. The MC55 is used as the GPRS module to achieve communication between the gateway and the Internet. We write programs of hardware drivers, communication protocol, abnormal SMS alarm and time synchronization protocol based on the hardware platform. The communication distance, power consumption and data storage rate of the gateway are tested in paddy field. Tests results show that, in open area, the maximum distance of effective communication can reach 331.18m, the longest working hour without charging is 32days, the maximum storage rate is 849.7kbps, the packet loss rate is 0.686% under local network and 0.712% between local network and the internet. The gateway has the characteristics of stable operation, long-time-low-power consumption, long distance transmission and automatic alarm. It can meet the requirement of information acquisition of environmental monitoring in paddy field. © 2014 ACADEMY PUBLISHER. Source


Dai F.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | Dai F.,South China Agricultural University | Dai F.,National University of Singapore | Bergholt M.S.,National University of Singapore | And 4 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2014

Potato is one of the most important food in the world. Rapid and noninvasive identification of potato cultivars plays an important role in the better use of varieties. In this study, The identification ability of optical spectroscopy techniques, including near-infrared (NIR) Raman spectroscopy and NIR fluorescence spectroscopy, for invasive detection of potato cultivars was evaluated. A rapid NIR Raman spectroscopy system was applied to measure the composite Raman and NIR fluorescence spectroscopy of 3 different species of potatoes (98 samples in total) under 785 nm laser light excitation. Then pure Raman and NIR fluorescence spectroscopy were abstracted from the composite spectroscopy, respectively. At last, the partial least squares- discriminant analysis (PLS-DA) was utilized to analyze and classify Raman spectra of 3 different types of potatoes. All the samples were divided into two sets at random: the calibration set (74samples) and prediction set(24 samples). the model was validated using a leave-one-out, cross-validation method. The results showed that both the NIR-excited fluorescence spectra and pure Raman spectra could be used to identify three cultivars of potatoes. The fluorescence spectrum could distinguish the Favorita variety well (sensitivity: 1, specificity: 0.86 and accuracy: 0.92), but the result for Diamant (sensitivity: 0.75, specificity: 0.75 and accuracy: 0.75) and Granola (sensitivity: 0.16, specificity: 0.89 and accuracy: 0.71) cultivars identification were a bit poorer. We demonstrated that Raman spectroscopy uncovered the main biochemical compositions contained in potato species, and provided a better classification sensitivity, specificity and accuracy (sensitivity: 1, specificity: 1 and accuracy: 1 for all 3 potato cultivars identification) among the three types of potatoes as compared to fluorescence spectroscopy. Source


Dai F.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | Dai F.,China Agriculture Research System | Dai F.,South China Agricultural University | Cai B.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | And 6 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

In order to provide a scientific basis for litchi quick and nondestructive detection and classification based on litchi internal quality, the nondestructive testing approach of litchi soluble solids content was studied. First, in the light of litchi hard and rough pericarp, results of diffuse reflectance and transmission experimental methods were compared. And then a variety of pretreatment methods were used to process diffuse transmission spectroscopy. The successive projections algorithm combined with correlation coefficient method was used to select optimal modeling wavelength. At last, partial least squares model and neural network model were built to predict the SSC of litchi. The results showed that diffuse transmission method was better than diffuse reflectance method for litchi spectrum acquisition; After variable compression, 11 preferred wavelengths were extracted, only accounts for 2.2% of the total 500 wavelengths; Based on the 11 wavelengths, the correlation coefficient of the BPNN model for predicted SSC of litchi was 0.867, and the root mean square error was 0.370%. The results indicate that the nondestructive detection for litchi soluble solids content based on diffuse transmission method is feasible. Source


Wen T.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | Wen T.,Machinery Laboratory of China Agriculture Citrus Research System | Wen T.,South China Agricultural University | Hong T.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | And 8 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2011

The number of Bactrocera Dorsalis in occurring period is the important parameter which threats the growth situation for fruit trees and is the basis of implementing variable rate technology. In order to realize detecting the occurrence of Bactrocera Dorsalis real-time and fasting in large-scale orchard, machine vision technologies based on moving object trace tracking were employed to trace Bactrocera Dorsalis behavies around traps real-time, so as to achieve statistics of their number into the hole precisely. The fore 50000 video image were selected as evaluation samples which collected in feed room of Resource and Environment College in South China Agricultural University using vision monitoring platform for Bactrocera Dorsalis. Through comparison of results with methods of artificial and machine vision detecting, the experiment indicated that the number of Bactrocera Dorsalis detected by artificial and machine vision were 85 heads and 78 heads, respectively. The loss rate of detecting using machine vision was 9.4%, which can meet the demands of pests' monitoring. Source


Wen T.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | Wen T.,Machinery Laboratory of China Agriculture Citrus Research System | Wen T.,South China Agricultural University | Hong T.,Key Laboratory of Key Technology for South Agricultural Machinery and Equipment | And 10 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

China Nowadays, solar photovoltaic energy applications has been penetrated into all areas of industrial and agricultural manufacturing in China. Due to fluctuation and randomness of solar radiation, solar efficiency was not fully utilized and operation devices were vulnerable to damages because of unstable power supplies. In this paper, regular silicon solar batteries were studied and the intelligent detection technology based on perturbation and observation was employed to track maximum power point of silicon solar battery and applied to the solar power equipment. By comparing the traditional method and the (maximum power point tracking) MPPT method, the experiment indicated that power outputs using MPPT method improved 11% compared with that by traditional method and suppressed power supply fluctuation effectively. Source

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