Study On Identification And Damage Mechanism Of Primary Drug Plants Under Low Contrast Conditions

At present,the problem of drugs at home and abroad is still very serious.Monitoring and eradicating the original plants of drugs is an important means to combat drug crime and curb the spread of drugs.In recent years,China’s use of satellites and flight platforms to monitor the illegal cultivation of the original plant drugs has reached the international advanced level,but the technical research and development work on the eradication of the original drug plants lags behind,it is still rely on time-consuming and laborious manual removal in the actual work of drug eradication.With the increase in the intensity of the fight against drugs in recent years,the cultivation of opium poppy has become a trend of secrecy,and the illicit cultivation of opium poppy has also been more in the deserted mountainous regions.Therefore,the means of killing opium poppy should be combined with poppy identification to complete the killing task.In this paper,from the perspective of physically eliminating the opium poppy,the identification of poppy seedlings under the low contrast condition and the laser-killing of poppy seedlings were studied.The specific research contents and their innovations include:1.Taking into account the influence of atmospheric optical properties on the identification and extermination of poppy,especially in the natural environment,the effects of atmospheric absorption has great effect on the spectral reflectance detection of poppies and turbulence on the laser transmission.Therefore,a brief introduction and analysis of atmospheric optical properties and turbulence effects in laser atmospheric transmission are presented.2.The reflectance spectra of the poppy leaves and the absorption spectra of the leaves at different times were studied.In order to study the spectral characteristics of poppy leaves,the average spectral reflectance of poppy seedlings at different periods was measured.Then,the reflectance spectra of opium poppy,corn poppy,wheat,and green bristlegrass were measured.Stepwise discriminant analysis methods in SPSS software were used to screen out the characteristic wavelengths for identifying poppies.Through the analysis of the absorption spectrum of poppy,and considering the factors such as plant growth characteristics,laser thermal efficiency and cost,the selected laser wavelength was 980 nm.3,Using 980nm wavelength laser,the laser extermination experiment on various organs of poppy were designed and carried out.The experiment uses a fixed distance and exposure time to obtain different power densities by varying the laser’s input current.The laser irradiation thresholds that act on the leaves,flowers,main stems,and fruits of the poppy were obtained.Based on the analysis of the experimental results and the analysis of the growth characteristics of poppy,we determined the strategy of extermination on poppy seedlings.4.Comparative analysis of popular deep learning algorithms in recent years,such as R-CNN,Fast R-CNN,Faster R-CNN,etc.,as the number of network layers increases,the gradient will be lost first,and the information of small target is likely to be covered up in the pooling process,so it is not appropriate for Poppy identification.In this study,the spectral identification method was applied to the improvement of the algorithm.According to the spectral reflectance characteristics of poppy,the candidate regions were screened out.DenseNet networks,which can effectively prevent loss of gradients,were used to identification at last.