Abstract-In many applications, the location information should be necessary. This paper propose a cheap multiplane 3D localization solution, which based on the existing 2D localization system, a perpendicular 2D plane is added to achieve 3D localization. The algorithm is intended for applications which require information of the height, but remain less sensitive to the location accuracy. At the same time, this paper also introduces symmetrical double-sided two-way ranging (SDS-TWR) and dynamic power consumption intensity searching algorithm into localization system, which can effectively lessen the influence of time synchronization and ease internet traffic congestion of wireless localization network.
Abstract. The presence of salt-and-pepper noise in speckle image prevents the precise measurement of deformation and displacement fields in the traditional digital image correlation (DIC) technique. Spearman's rho (SR) has been introduced as a kernel correlation function in the DIC. The robustness of SR is quantitatively analyzed in following two cases: one is speckle images contaminated by same distribution salt-and-pepper noise, and the other is contaminated by random distribution noise. Theoretical and simulation results suggest that the DIC using SR is robust to about 10% salt-and-pepper noise. SR is suitable for measurement deformation and displacement fields.
Global warming might expand crop growth areas for the prevailing single and double rice cropping systems in Southern China. Based on historical weather and crop data from 1981 to 2015, we evaluated the economic benefit and environmental cost for single and double rice cropping systems (SRCS and DRCS) in areas that are sensitive to climate variability in the middle and lower reaches of the Yangtze River. The five chosen indices were: net profit, agronomic nitrogen use efficiency (ANUE), water use efficiency (WUE), total amount, and global warming potential (GWP) of greenhouse gas (GHG). The goal of this study is to provide scientific evidence for local policymakers to use in selecting the most suitable rice cropping systems to maximize economic profits while adapting to climate change. The results showed that net profit was $171.4 per hectare higher for DRCS than for SRCS in the study region. In addition, output per unit nitrogen usage was $0.25 per kg N higher for DRCS than for SRCS. Net profit would increase if DRCS replaced SRCS, and the maximum amplitude of increase in net profit for this replacement occurred under the settings of 150 kg ha−1 nitrogen fertilizer level and continuous irrigation when the paddy water layer started to fade. On the other hand, annual variation in net profit for SRCS was consistently smaller than DRCS, regardless of changes in nitrogen fertilizer level and irrigation regime settings. SRCS showed better WUE than DRCS in both rainfed and irrigated situations, as well as lower seasonal CH4 and N2O emissions during the study period. Therefore, we conclude that SRCS is superior to DRCS for the sake of maximizing economic profit while maintaining sustainable agriculture in areas that are sensitive to climate variability in the middle and lower reaches of the Yangtze River.
The robustness and computational efficiency of digital image correlation (DIC) are two key influencing factors for displacement field measurement applications. Especially when the speckle images are contaminated by salt-and-pepper noise, it is difficult to obtain reliable measurement results using traditional DIC methods. Digital image Spearman’s Rho Correlation (DISRC), as a new DIC technique, has certain robustness to salt-and-pepper noise, but incurs a high computational load when computing subset ranks. It is found that the DISRC can tolerate up to 15% noise level theoretically by analyzing the mean character of Spearman’s Rho. Meanwhile a fast scheme is proposed in which parallelization is adopted for precomputing subset rank and computing for displacement field to accelerate the DISRC. The simulation results indicate that the fast DISRC is about 60 times faster than the original one, and the displacement field results are almost the same between them. The DISRC not only gives as well results as zero-mean normalized cross-correlation (ZNCC) without any noise, but also can tolerate 20% noise level in simulations. A case study also verifies that the result by DISRC is better than ZNCC when contaminated by smaller amounts of noise. The conclusion is that the DISRC is a strong anti-interference DIC technique, which is very important in application under complex environment, and the fast scheme is an effective way to accelerate the DISRC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.