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931.
Scientometrics - Technology is a complex system with technologies relating to each other in a space that can be mapped as a network. The technology network’s structure can reveal properties...  相似文献   
932.
933.
Journal of Materials Science - TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl)-oxidized cellulose nanofibrils (T-CNF) and silver nanowires (Ag NWs) were formulated as active inks. Their rheological...  相似文献   
934.
A possible way of improving the activity and selectivity profile of antitumor agents is to design drug carrier systems employing soluble macromolecules. Thus, four resorcinarene-PAMAM-dendrimer conjugates of chlorambucil with different groups in the lower part of the macrocycle and different length dendritic arms showed a good stability of the chemical link between drug and spacer. Evaluation of the cytotoxicity of the resorcinarene-PAMAM-dendrimer–chlorambucil conjugate employing a sulforhodamine B (SRB) assay in K-562 (human chronic myelogenous leukemia cells) demonstrated that the conjugate was more potent as an antiproliferative agent than chlorambucil.  相似文献   
935.
Santos  João M.  Horta  Hugo  Li  Huan 《Scientometrics》2022,127(7):3719-3747
Scientometrics - This study analyzes the association between the strategic research agendas of researchers in the social sciences and their research performance. Based on a worldwide sample of 604...  相似文献   
936.
In this paper, we prove the interior approximate controllability of the impulsive semilinear heat equation with delay in control and in state by proving first that the linear heat equation with delay in control is approximately controllable. After that, we add impulses and a nonlinear perturbation with delay in state, and using Rothe's fixed point theorem, we prove that the interior approximate controllability of the impulsive semilinear system. Finally, we present some open problems and a possible general framework to study the controllability of impulsive semilinear diffusion process in Hilbert spaces with delay in control and in state.  相似文献   
937.
The problem of robust control applied to adjust the configuration of an ankle prosthesis based on disturbance estimation has been addressed in this study. Active disturbance rejection control was the paradigm used for controlling the robotic prosthesis by means of a direct active estimation. Based on this active estimation, the robust controller implemented the disturbance cancellation providing a fast converge to the origin of the tracking error. The uncertainties affecting the prosthesis dynamics were identified by a high‐order extended state high gain observer. This identification was used to force the tracking between the actual position and force needed in the ankle prosthesis and some reference values obtained by a biomechanical gait cycle analysis. Therefore, the estimated states were used to implement a robust output feedback controller that was effective to reject actively the perturbations. This rejection implemented within the controller forced the trajectory tracking to a small vicinity of the origin. A strategy based on composite Lyapunov function served to prove that tracking problem for the prosthesis was successfully solved despite the switching nature of the gait cycle. The controller was implemented in numerical simulations for showing the convergence of the tracking error. The convergence of this tracking error to the region around the origin was obtained within the first second of simulation.  相似文献   
938.
Water Resources Management - The nonlinear Muskingum model is a leading method for hydrologic routing. The efficiency of the nonlinear Muskingum model for routing of hydrograph outflow has been...  相似文献   
939.

To tackle the complex problem of providing business intelligence solutions based on business data, bioinspired deep learning has to be considered. This paper focuses on the application of artificial metaplasticity learning in business intelligence systems as an alternative paradigm of achieving a deeper information extraction and learning from arbitrary size data sets. As a case study, artificial metaplasticity multilayer perceptron applied to the automation of credit approval decision based on collected client data is analyzed, showing its potential and improvements over the state-of-the-art techniques. This paper successfully introduces the relevant novelty that the artificial neural network itself estimates the pdf of the input data to be used in the metaplasticity learning, so it is much closer to the biologic reality than previous implementations of artificial metaplasticity.

  相似文献   
940.
Neural Computing and Applications - Missing values in a dataset is one of the most common difficulties in real applications. Many different techniques based on machine learning have been proposed...  相似文献   
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