23 research outputs found
Meta Learning MPC using Finite-Dimensional Gaussian Process Approximations
Data availability has dramatically increased in recent years, driving
model-based control methods to exploit learning techniques for improving the
system description, and thus control performance. Two key factors that hinder
the practical applicability of learning methods in control are their high
computational complexity and limited generalization capabilities to unseen
conditions. Meta-learning is a powerful tool that enables efficient learning
across a finite set of related tasks, easing adaptation to new unseen tasks.
This paper makes use of a meta-learning approach for adaptive model predictive
control, by learning a system model that leverages data from previous related
tasks, while enabling fast fine-tuning to the current task during closed-loop
operation. The dynamics is modeled via Gaussian process regression and,
building on the Karhunen-Lo{\`e}ve expansion, can be approximately reformulated
as a finite linear combination of kernel eigenfunctions. Using data collected
over a set of tasks, the eigenfunction hyperparameters are optimized in a
meta-training phase by maximizing a variational bound for the log-marginal
likelihood. During meta-testing, the eigenfunctions are fixed, so that only the
linear parameters are adapted to the new unseen task in an online adaptive
fashion via Bayesian linear regression, providing a simple and efficient
inference scheme. Simulation results are provided for autonomous racing with
miniature race cars adapting to unseen road conditions
Efeito da fonte de nitrogênio e teor de proteína bruta da dieta sobre o balanço de nitrogênio e o desempenho produtivo de vacas leiteiras
The aim of the present study was to evaluate the effect of two crude protein contents (CP) and two main nitrogen sources in the diet of dairy cows, using sugarcane as forage, on intake, total apparent digestibility, milk yield and composition, and nitrogen balance. Twelve Holstein cows in late lactation were assigned in three contemporary square, in a Latin Square design 4 × 4, with 2 × 2 factorial treatment arrangement, in 21-day trial by period, 14 for diet adaptation and the last seven for sampling and analysis. Cows were housed in individual stalls and fed a total mixed ration (TMR) "ad libitum" composed of two main nitrogen sources (cottonseed meal or whole raw soybean grain) and two levels of CP (130g or 148g/kg dry matter - DM) in the diet. In the present study, there was an interaction effect between nitrogen source and crude protein on DM intake (DMI). Cows fed whole raw soybean had higher DMI when the CP content of the diet was 130 g CP/kg DM, while cows fed cottonseed meal had higher DMI when the CP content of the diet was 148 g CP/kg DM. A similar result of DMI was observed for organic matter intake, whereas there was no interaction effect between dietary nitrogen source and crude protein content on intake of other nutrients. Total apparent digestibility of NDF and TDN was higher when soybean was used as the main diet nitrogen source; whereas the digestibility of dietary CP was not changed by the nitrogen sources. Although there were changes in the DMI and the apparent digestibility coefficient, in the current study, there was no effect of dietary crude protein content and nitrogen source on milk yield. In conclusion, the use of low dietetic concentrations of crude protein (130 g/Kg of DM) does not change the lactating performance of dairy cows and may reduce diet cost, while the choice between whole raw soybean grain or cottonseed meal as a protein ingredient may depends only on the availability and/or price, as both ingredients result in similar performance.O objetivo do presente estudo foi avaliar o efeito de dois teores proteicos (PB) e duas fontes nitrogenadas na dieta de vacas leiteiras, utilizando cana-de-açúcar como forragem, sobre o consumo, digestibilidade aparente total, produção e composição do leite, e o balanço de nitrogênio. Doze vacas leiteiras Holandesas em estágio intermediário de lactação foram distribuídas em três quadrados contemporâneos, em um delineamento em quadrado latino 4 × 4, com arranjo fatorial de tratamentos 2 × 2, em períodos de 21 dias, onde os primeiros 14 dias foram destinados para a adaptação às dietas e os últimos sete para as coletas de dados e análises. As vacas foram alocadas em baias individuais em um sistema free-stall, e alimentadas com dietas totalmente misturada (TMR) “ad libitum” compostas por duas fontes nitrogenadas principais (farelo de algodão ou grão de soja crú integral) e dois níveis de proteína (130 g ou 148 g/kg de matéria seca- MS). No presente estudo, houve efeito de interação entre a fonte nitrogenada e o teor de PB sobre o consumo de MS (CMS). As vacas alimentadas com grão de soja crú integral tiveram maior CMS quando o teor de PB da dieta foi de 130 g CP/kg MS, enquanto que as vacas alimentadas com farelo de algodão apresentaram maior CMS quando o teor de PB da dieta foi de 148 g PB/kg MS. Resultado semelhante ao CMS foi observado para o consumo de matéria orgânica, enquanto que não houve efeito de interação entre fonte nitrogenada e teor de PB sobre o consumo dos demais nutrientes dietéticos. A digestibilidade aparente total da FDN foi maior quando grão de soja crú integral foi utilizado como principal fonte nitrogenada da dieta; enquanto que a digestibilidade da PB não foi alterada pelas fontes nitrogenadas. Apesar de haver alterações no CMS e na digestibilidade aparente total, no presente estudo, não houve efeito de teor de PB e fonte nitrogenada sobre a produção de leite. Como conclusão, o uso de baixo teor dietético de PB (130 g PB/kg de MS) não altera o desempenho produtivo de vacas leiteiras e pode reduzir os custos da dieta, enquanto que a escolha entre grão de soja cru integral e farelo de algodão como principais fontes nitrogenadas da dieta pode depender apenas da disponibilidade e custo, uma vez que ambos ingredientes apresentam desempenhos semelhantes
Development of hypogammaglobulinemia in patients treated with imatinib for chronic myeloid leukemia or gastrointestinal stromal tumor
Imatinib mesylate is a tyrosine kinase inhibitor used as first line treatment in chronic myeloid leukemia and gastrointestinal stromal tumor patients. Although several in vitro and animal studies demonstrated that imatinib affects immune response, few immune alterations are described in humans. We retrospectively studied hematologic and immunological parameters in 72 chronic myeloid leukemia and 15 gastrointestinal stromal tumor patients treated with imatinib at standard dosage and in 20 chronic myeloid leukemia patients treated before the introduction of imatinib in clinical practice. Both chronic myeloid leukemia and gastrointestinal stromal tumor patients developed a significant reduction of gammaglobulin and immunoglobulin serum levels. No significant hypogammaglobulinemia was observed in chronic myeloid leukemia patients in the pre-imatinib era. These data demonstrate that imatinib treatment induces hypogammaglobulinemia that can reach a severe entity in 10% of cases, both in chronic myeloid leukemia and in gastrointestinal stromal tumor patients. Prospective studies are needed to evaluate immune humoral alterations and to define the real incidence of infectious events, including viral reactivations
Type A Insulin Resistance Syndrome- Novel insulin receptor gene mutation and familiar phenotypic variability
Type A Insulin Resistance Syndrome is due to heterozygous mutations in the insulin receptor (INSR) gene or its signaling pathway. We present a premenarcheal 14 year-old girl with normal BMI, severe hirsutism, acanthosis nigricans, clitoral hypertrophy, deep voice, enlarged polycystic ovaries, severe hyperinsulinemia and biochemical hyperandrogenism.We identifi ed a novel heterozygous missense variant in the tyrosine kinase domain of INSR(p.Leu1150Pro) and an heterozygous missense variant in SH2B adapter protein 1 involved in the insulin pathway (p.Ala663Val). Interestingly, the patients? mother and brother had the same INSR mutation although of a milder phenotype, reason why their IR went undiagnosed.The novel heterozygous p.Leu1150Pro mutation in the INSR gene appears to be the cause of the type A insulin resistance syndrome; the SH2B1 mutation, likely to synergistically affect the insulin pathway, may contribute to explain the more severe presentation of the phenotype in the patient and the phenotypic variability of the syndrome within this family.Fil: Freire, Analia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Scaglia, Paula Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Gryngarten, Mirta Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Gutiérrez, Mariana Lilián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Arcari, Andrea Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Suarez, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Ballerini, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Valinotto, Laura Elena. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Natale, Mónica Inés. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; Argentina. Universidad de Buenos Aires; ArgentinaFil: Del Toro Camargo, Kenny. No especifíca;Fil: Bergada, Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Rey, Rodolfo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Ropelato, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; Argentin
A Fast Method for Real-Time Chance-Constrained Decision with Application to Power Systems
ISSN:2475-145
Salt Lake City, 1950: Sheet 254
300 East; Third East; 400 East; Fourth East; 300 South; Third South; 400 South; Fourth South; Amos Villa; Laroda Court; Owen Plac
Error Analysis of Regularized Trigonometric Linear Regression With Unbounded Sampling: A Statistical Learning Viewpoint
The effectiveness of non-parametric, kernel-based methods for function estimation comes at the price of high computational complexity, which hinders their applicability in adaptive, model-based control. Motivated by approximation techniques based on sparse spectrum Gaussian processes, we focus on models given by regularized trigonometric linear regression. This letter provides an analysis of the performance of such an estimation set-up within the statistical learning framework. In particular, we derive a novel bound for the sample error in finite-dimensional spaces, accounting for noise with potentially unbounded support. Next, we study the approximation error and discuss the bias-variance trade-off as a function of the regularization parameter by combining the two bounds.ISSN:2475-145
Old Santa Fe, a magazine of history, archaeology, genealogy and biography, volume 2, no. 5 (July 1914): Creation of the Zunis
Pages 79-83, 86-87 from an article by Florence Bartlett in "Old Santa Fe, a magazine of history, archaeology, genealogy and biography," volume 2, no. 5 (July 1914), an account of the Zuni creation story, including the importance of "Koh-thlou-wala-wa," the sacred site near the confluence of the Zuni and Little Colorado river