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The loop-mediated isothermal amplification (LAMP) primers were designed for the conserved region of the selected Nicotiana-specific gene Ntsp151 sequence, and a visual LAMP detection method for tobacco materials based on the SYBR Green I was established. The genomic DNA extraction method and reaction conditions were optimized in the detection process. Furthermore, the specificity and sensitivity of the LAMP reaction system were evaluated. The results showed that the genomic DNA extracted by Chelex-100 could be directly amplified and fluorescently colored by LAMP; the optimal reaction conditions of the LAMP primers were amplification temperature 63 °C, reaction time 60 min, Mg2+ concentration 6 mmol/L; LAMP detection method had good specificity and the results of chromogenic amplification and fluorescence detection of 17 non-tobacco materials and 1 tobacco material were consistent and had good specificity. The sensitivity test showed that the minimum detection limit of the LAMP reaction system was 102 copies/μL. The LAMP detection based on Nicotiana-specific gene Ntsp151 was result-visualized, highly sensitive, and specific, which was suitable for field inspection. [ABSTRACT FROM AUTHOR]

Visibility analysis is one of the most important parts of the spatial analysis in geographic informa⁃ tion system, which is calculated based on the measurable models. However, it is hard to construct accurate models for the huge number of objects automatically because there is a mess of various objects in the urban area. Mobile laser scanning can acquire accurate three⁃dimensional information together with other physical properties (such as reflected intensity, echo waveform, etc.) on road and along roadside flexibly and effi⁃ ciently, which provides an alternative data source for visibility analysis of the large⁃scale road scenes. This paper proposes a fast and robust depth ⁃ buffering method to analyze visibility based on point cloud data in road scenes efficiently and robustly. To achieve the goal, an adaptive spatial index construction strategy is firstly introduced based on the viewpoint and the corresponding field of view. Then the viewshed between the viewpoint and the field of view is analyzed efficiently using the depth⁃buffering method. The visualizing degree from the road to the traffic sign and the illuminated region on road of the street lamps are estimated respectively to verify the feasibility as well as the flexibility of the proposed method. The performance of the experiments shows that the proposed method can assist in monitoring the infrastructure health and deci⁃ sion support for the municipal planning department. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of solar street lamp system, the maximum power point tracking (MPPT) method was applied to its controller. After the analysis of MPPT principle, specific methods to implement MPPT and drive Buck circuit were proposed. Also, by using AVR Studio program and Multisim and Proteus as the platform, a control system based on ATmega16 was finally built. On the basis of a simulation test that was passed, the experiment was conducted. The results show that the duty cycle of PWM waves is in accordance with the empirical value, which indicates that the solar panel charges the storage battery with maximum power, and the controller charges and discharges the battery in a scientific way. [ABSTRACT FROM AUTHOR]