Search results for "Principle"
showing 10 items of 1023 documents
The flex end-to-end simulator: From concept phase (A/B1) to ground segment and operations (C/D)
2018
ESA's FLEX/Sentinel-3 tandem mission aims at mapping Sun-induced fluorescence (SIF) as a proxy to quantify photosynthetic activity of terrestrial vegetation. Due to the complexity of the mission concept and stringent requirements for the data processing algorithms, ESA developed a Phase A/B1 End-to-End Mission Performance Simulator (E2ES) tool to reproduce the expected mission performance and check the mission and instrument concepts. In the current Phase C/D, the E2ES concept must evolve to consolidate the whole data processing chain, providing an accurate figures of the whole mission error budget and serving as a roadmap for the future development of FLEX Ground Segment. This paper gives …
Gauge theory of the long-range proximity effect and spontaneous currents in superconducting heterostructures with strong ferromagnets
2017
We present the generalized quasiclassical theory of the long-range superconducting proximity effect in heterostructures with strong ferromagnets, where the exchange splitting is of the order of Fermi energy. In the ferromagnet the propagation of equal-spin Cooper pairs residing on the spin-split Fermi surfaces is shown to be governed by the spin-dependent Abelian gauge field which results either from the spin-orbital coupling or from the magnetic texture. This additional gauge field enters into the quasiclassical equations in superposition with the usual electromagnetic vector potential and results in the generation of spontaneous superconducting currents and phase shifts in various geometr…
Smart urbanism
2020
A characteristic of intelligent cities is urban development where local and national governments regulate land use plans in order to efficiently plan and control urban and real state growth.This article describes the case of use in urban licensing in the government of Colombia in which a digitalization system was designed and developed in the public administration where data collection, storage and analysis are carried out to control urban licensing in 37 cities of Colombia. The system allows visual and statistical analysis of the urban growth of the cities.The results obtained by the system have allowed to improve the control and legality of the construction licenses in Colombia and has co…
Robustness with Respect to Delay Uncertainties of a Predictor-Observer Based Discrete-Time Controller
2006
This paper focuses on the delay-dependent stability problem of a discrete-time prediction scheme to stabilize possible unstable continuous-time systems. The delay-dependent stability condition is expressed in terms of LMIs. The separation principle between the proposed predictor and a state observer is also proved. The closed-loop system is shown to be robust with respect to uncertainties in the knowledge on the plant parameters, the delay and the sampling period. The proposed scheme has been tested in a real-time application to control the roll angle in a prototype of a quad-rotor mini-helicopter.
Periodic Controls in Step 2 Strictly Convex Sub-Finsler Problems
2020
We consider control-linear left-invariant time-optimal problems on step 2 Carnot groups with a strictly convex set of control parameters (in particular, sub-Finsler problems). We describe all Casimirs linear in momenta on the dual of the Lie algebra. In the case of rank 3 Lie groups we describe the symplectic foliation on the dual of the Lie algebra. On this basis we show that extremal controls are either constant or periodic. Some related results for other Carnot groups are presented. peerReviewed
A predictive learning approach to optimal load sharing in energy management systems
2019
Given the total power demand, $P_{d}$ , current practice of equal load sharing in the process industry is to distribute the load among power supply units and machines (e.g., diesel/aas/wind turbines) in proportion to the maximum power, i.e., $P_{i}=\frac{p_{\max}^{i}}{\sum_{j}P_{\max}^{j}}P_{d}$ , where $P_{\max}^{i}$ denotes the maximum power of the ithunit. However, the efficiency of power supply units, vary in time and are highly individual, even in the case of units from same brand and model. Thus, by considering and utilizing these individual differences, it is possible to share the load in a more fuel/cost/energy optimal manner. To capture this potential, the work presented in this pa…
Application of modern computer algebra systems in food formulations and development: A case study
2017
Abstract Background Nutritional security determines the level of public health within a population while inadequate nutrition is one of the major factors in development of various health problems. This can be alleviated with sufficient and affordable access to currently available or newly designed nutritious foods. Scope and approach Formulation of new foods can be very costly, so methods able to lower design expanses are of utmost importance to the industry. Hence, the purpose of this work was to rationalize utilization of modern computerized algebraic systems (CAS) in solving traditional problems for formulating food mixtures by food combinatoric principles (FCP). Key findings and conclus…
Objective Assessment of Nuclear and Cortical Cataracts through Scheimpflug Images: Agreement with the LOCS III Scale.
2016
Purpose To assess nuclear and cortical opacities through the objective analysis of Scheimpflug images, and to check the correlation with the Lens Opacity Classification System III (LOCS III). Methods Nuclear and cortical opacities were graded according to the LOCS III rules after pupil dilation. The maximum and average pixel intensity values along an elliptical mask within the lens nucleus were taken to analyse nuclear cataracts. A new metric based on the percentage of opaque pixels within a region of interest was used to analyse cortical cataracts. The percentage of opaque pixels was also calculated for half, third and quarter areas from the region of interest’s periphery. Results The maxi…
Modified Vitrectomy Technique for Phakic Rhegmatogenous Retinal Detachment with Intermediate Break
2018
Purpose. To evaluate the effects of a modification of the traditional 25-gauge pars plana vitrectomy technique in the treatment of uncomplicated macula-on rhegmatogenous retinal detachment (RRD) with intermediate retinal break(s) and marked vitreous traction in the phakic eye. Methods. Prospective, noncomparative, and interventional case series. All consecutive phakic eyes with primary uncomplicated macula-on RRD with intermediate retinal break(s) and marked vitreous traction, with at least 1 year of postoperative follow-up, were enrolled. In all eyes, “localized 25-gauge vitrectomy” under air infusion with localized removal of the vitreous surrounding the retinal break(s), in association w…
Food Processing at a Crossroad
2019
Recently, processed foods received negative images among consumers and experts regarding food-health imbalance. This stresses the importance of the food processing—nutrition interface and its relevance within the diet-health debates. In this review, we approach the related questions in a 3-fold way. Pointing out the distinguished role food processing has played in the development of the human condition and during its 1.7 million year old history, we show the function of food processing for the general design principles of food products. Secondly, a detailed analysis of consumer related design principles and processing reveals questions remaining from the historical transformation from basic…