The combination of machine vision and non-destructive testing can achieve multi-dimensional evaluation of welds. This paper proposes a weld evaluation method based on the combination of line structured light and weak magnetic detection technology. The weak magnetic detection technology is used to detect the internal defects of the weld; the line structured light sensing system is used to measure the lift-off of the weak magnetic sensor and the weld, the stability of the weak magnetic detection signal is ensured, and a relationship between lift-off and peak-to-peak value model is established to provide data support for defect size discrimination; during the automatic detection process, the line structured light system is used to reconstruct the three-dimensional morphology of the weld pool surface to obtain high-precision weld profile and detect weld surface defects. The experimental device was designed and the aluminum plate weld inspection experiment was carried out. The experimental results show that the proposed method can quickly and accurately represent the weld surface morphology, and the detection effect of weak magnetic sensor on weld defects can be improved, this provides a new idea for improving the weld detection technology in practical engineering applications.
KEYWORDS: Methane, Data modeling, Atmospheric modeling, Climate change, Climatology, Temperature metrology, Geographic information systems, Systems modeling, Data centers, Agriculture
Paddy field is a major source of methane (CH4) emission. Methane emission in paddy fields accounts for 31.5% of agricultural methane emissions in China. Double-rice cropping system is a part of the major paddy systems in China for rice production, accounting for only 27% of the national rice planting area while CH4 emission accounting for 60% of the national CH4 emission. Given the importance of reducing CH4 emission from double rice to mitigate climate warming, it is necessary to investigate the impact of climate change on CH4 emission of double cropping paddy field in the future. In this study, the denitrification–decomposition (DNDC-a process-based biogeochemistry model) model is employed to simulate the CH4 emission from double-rice cropping system in southern China based on the historical meteorological data of the past 50 years (1966-2015) and the observational data of rice agricultural stations in the study area. Then we combined the outputs with Geographic Information System (GIS) technology to analyze the impact of climate change on CH4 emissions from the double rice paddy. The results indicate that change of the average temperature is associated with the change of CH4 emission across the growing period of double rice paddy. Methane has increased by 8.4% in the main producing provinces of double cropping rice in southern China. Zhejiang has increased by up to 20.8%. Anhui, Hubei, Hunan has increased by 10.6%, 10.2% and 11.4%. The relatively small increase in Fujian and Yunnan is only 5%. However, in the low latitudes of Guangxi, and Guangdong province, there was a slight reduction in CH4 emission.
Chinese yam (Dioscorea opposita Thunb.) is consumed and regarded as medicinal food in traditional Chinese herbal medicine, Chinese medicinal yam especially is one of the most important Chinese herbal medicines and its medicinal needs have been increasing in recent decades1. Furthermore, Chinese medicinal yam is susceptible to climate conditions during the growth period. Therefore, a better understanding of the suitability regionalization of Chinese medicinal yam under the impact of climate change is of both scientific and practical importance to spacial development and reasonable layout of Chinese yam in China. In this study, based on the Coupled Model Inter-comparison Project, Phase 5 (CMIP5) climate model projections with 5 Global Circulation Models (GCMs) developed by the Inter-Sectoral Impact Model Inter-comparison Project (ISIMIP) driven by 4 Representative Concentration Pathways (RCPs), we assessed the changes of potential planting area of Chinese medicinal yam between the baseline climatology of 1981-2010 and the future climatology of the 2050s (2041-2070) under the RCP 4.5 scenario by the Geographic Information System (GIS) technology. Results indicate that regions with high ecological similarity to the Geo-authentic producing areas of Chinese medicinal yam include northeastern Henan, southeastern Hebei and western Shandong, mainly distribute in the lower reaches of the Yellow River basin and other major floodplains. In the future, the climate suitability of Chinese medicinal yam in these areas will be weakened, but that will still be the main suitable planting regions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.