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91.
Keerthy Kusumam Tomáš Krajník Simon Pearson Tom Duckett Grzegorz Cielniak 《野外机器人技术杂志》2017,34(8):1505-1518
This paper describes a 3D vision system for robotic harvesting of broccoli using low‐cost RGB‐D sensors, which was developed and evaluated using sensory data collected under real‐world field conditions in both the UK and Spain. The presented method addresses the tasks of detecting mature broccoli heads in the field and providing their 3D locations relative to the vehicle. The paper evaluates different 3D features, machine learning, and temporal filtering methods for detection of broccoli heads. Our experiments show that a combination of Viewpoint Feature Histograms, Support Vector Machine classifier, and a temporal filter to track the detected heads results in a system that detects broccoli heads with high precision. We also show that the temporal filtering can be used to generate a 3D map of the broccoli head positions in the field. Additionally, we present methods for automatically estimating the size of the broccoli heads, to determine when a head is ready for harvest. All of the methods were evaluated using ground‐truth data from both the UK and Spain, which we also make available to the research community for subsequent algorithm development and result comparison. Cross‐validation of the system trained on the UK dataset on the Spanish dataset, and vice versa, indicated good generalization capabilities of the system, confirming the strong potential of low‐cost 3D imaging for commercial broccoli harvesting. 相似文献
92.
To allow efficient and user‐friendly development of a component‐based application, component systems have to provide a rather complex development infrastructure, including a tool for component composition, component repository, and a run‐time infrastructure. In this paper, we present and evaluate benefits of using meta‐modeling during the process of defining a component system and also during creation of the development and run‐time infrastructures. Most of the presented arguments are based on a broad practical experience with designing the component systems SOFA and SOFA 2; the former designed in a classical ad hoc ‘manual’ way, whereas the latter with the help of meta‐modeling. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
93.
We describe a new approach to the application of stochastic search in Inductive Logic Programming (ILP). Unlike traditional
approaches we do not focus directly on evolving logical concepts but our refinement-based approach uses the stochastic optimization
process to iteratively adapt the initial working concept. Utilization of context-sensitive concept refinements (adaptations)
helps the search operations to produce mostly syntactically correct concepts. It also enables using available background knowledge
both for efficiently restricting the search space and for directing the search. Thereby, the search is more flexible, less
problem-specific and the framework can be easily used with any stochastic search algorithm within ILP domain. Experimental
results on several data sets verify the usefulness of this approach. 相似文献
94.
95.
Štefan Černák 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(5):453-462
A convergence with a fixed regulator v in lattice ordered groups is applied to MV-algebras. For each Archimedean MV-algebra A there exists a v-Cauchy completion A
* and it is uniquely determined up to isomorphisms over A. The relation between the Dedekind completion A
∧ of A and A
* is established. There is solved a question of the existence of the greatest v-Cauchy complete ideal of A. 相似文献
96.
Using a new design of helium-methane gas-flow detector of conversion electrons for Mössbauer spectroscopy, non-uniform nucleation of the primary -Fe-Co phase on both contact and free surfaces of the Ar(+H2) annealed amorphous Fe75Co9B16 alloy was observed in its early crystallization stage. In this state the amount of crystalline phase on the contact ribbon side surpasses that on the free one by a factor of three, whereas no traces of volume crystallization were observed in the transmission spectra. By applying ion implantation to both ribbon surfaces, a slight reduction of the crystalline phase contribution was found. Magnetic domain structure observations were performed in order to evaluate the influence of surface crystallization on magnetic properties. 相似文献
97.
98.
99.
100.
P. Novk 《Electrochimica acta》1985,30(12):1687-1692
Discharge mechanisms of the cathode of Li-CuO cells proposed in the literature are discussed. On the basis of a comparison of the behaviour of the systems Li-CuO, Na-CuO and Li-Cu2O it is concluded that the discharge reaction involves intercalation of Li+ ions into the CuO lattice according to CuO + xe− + xLi+ → CuOLix. 相似文献