1,285 research outputs found
Regression and bee optimization to select Colombia investment portfolio
La decisión de seleccionar la cartera de inversión es muy compleja y se basa en el riesgo y la rentabilidad. Existen múltiples estudios sobre cartera de inversión, sin embargo, es un campo de investigación abierto debido a la complejidad de la predicción del mercado. En este trabajo se comparan modelos de regresión de vectores de soporte y memoria a largo plazo-red neuronal artificial aplicados en una base de datos de la bolsa de valores de Colombia de 18 empresas con 2631 instancias para el período 2010-2020. Sus resultados se utilizan para obtener una cartera de inversión optimizada que se lleva a cabo utilizando la optimización del algoritmo de abeja para minimizar el riesgo y maximizar la ganancia con niveles de restricción basados en el rendimiento esperado. Los resultados demostraron la capacidad del sistema de apoyo a la toma de decisiones para seleccionar la carteraMaking decision to select investment portfolio is very complex and it is based on the risk and the profit. There are multiple studies about investment portfolio, however, itisanopenresearchfieldduetothecomplexityofthepredictionofthe market. In this paper are compared support vector regression models and Long short term memory- Artificial Neural network applied on a database of Colombia stock-exchange of 18 enterprises with 2631 instances for the period 2010-2020. Theirresultsareusedtoobtainanoptimizedinvestmentportfoliowhichiscarried out using bee algorithm optimization in order to minimize the risk and maximize theprofitwithconstrainlevelsbasedonexpectedreturn. Theresultsdemonstrated the capability of the decision support system to select portfoli
Traffic characterization in a communications channel for monitoring and control in real-time systems
The response time for remote monitoring and control in real-time systems is a sensitive issue in device interconnection elements. Therefore, it is necessary to analyze the traffic of the communication system in pre-established time windows. In this paper, a methodology based on computational intelligence is proposed for identifying the availability of a data channel and the variables or characteristics that affect the performance and data transfer, which is made up of four stages: a) integration of a communication system with an acquisition module and a final control structure; b) communication channel characterization by means of traffic variables; and c) relevance analysis from the characterization space using SFFS (sequential forward oating selection); d) Channel congestion classification as Low or High using a classifier based on Naive Bayes algorithm. The experimental setup emulates a real process using an on/off remote control of a DC motor on an Ethernet network. The communication time between the client and server was integrated with the operation and control times, to study the whole response time. This proposed approach allows support decisions about channel availability, to establish predictions about the length of the time window when the availability conditions are unknown
Mean reversion in monetary aggregates in Chile.
In this paper we examine the statistical properties of the monetary aggregates in Chile in order to know if the time series display mean reverting behavior. For this purpose, we use techniques based on fractional integration. Monthly data of various Chilean monetary aggregates from January 1986 until August 2019 are used, and the results indicate very weak evidence of mean reversion. In fact, this property is only found in the case of the currency on circulation and M1 for some of the series examined; however, for M2 and M3 the results clearly show high persistence with orders of integration substantially higher than 1. Thus, shocks are expected to have a permanent nature in these cases. Another remarkable feature observed in the results is that the level of persistence in the series seems to grow with the amount of the monetary aggregate. In a multivariate context, performing a FCVAR model, evidence of cointegration is found among the monetary aggregates, finding a long run equilibrium relationship between them.pre-print395 K
Mediterranean alcohol-drinking pattern, low to moderate alcohol intake and risk of atrial fibrillation in the PREDIMED study
[Background and aims] There is ongoing controversy about the effect of a low to moderate alcohol consumption on atrial fibrillation (AF). Our aim is to assess the association between adherence to a Mediterranean alcohol drinking pattern and AF incidence.[Methods and results] A total 6527 out of the 7447 participants in the PREDIMED trial met our inclusion criteria. A validated frequency food questionnaire was used to measure alcohol consumption. Participants were classified as non-drinkers, Mediterranean alcohol drinking pattern (MADP) (10–30 g/d in men and 5–15 g/day in women, preferably red wine consumption with low spirits consumption), low-moderate drinking (<30 g/day men y and < 15 g/day women), and heavy drinking. We performed multivariable Cox regression models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) of incident AF according to alcohol drinking patterns. After a mean follow up of 4.4 years, 241 new incident AF cases were confirmed. Alcohol consumption was not associated to AF incidence among low-moderate drinkers (HR: 0.96; 95%CI: 0.67–1.37), adherents to MADP (HR: 1.15 95%CI: 0.75–1.75), or heavy drinkers (HR: 0.92; 95%CI: 0.53–1.58), compared with non-drinkers.[Conclusions] In a high cardiovascular risk adult population, a Mediterranean alcohol consumption pattern (low to moderate red wine consumption) was not associated with an increased incidence of AF.[Clinical trials] URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.PREDIMED trial was supported by the official funding agency for biomedical research of the Spanish government (Instituto de Salud Carlos III) RTIC G03/140 (Coordinator: Dr Estruch) and RTIC RD 06/0045 (Coordinator: Dr Martínez-González). We also acknowledge grants from the National Institutes of Health, United States (1R01HL118264-01); Fondo de Investigación Sanitaria– Fondo Europeo de Desarrollo Regional (PI04/0233, PI05/0976, PI07/0240, PI10/01407, PI10/02658, PI11/00049, PI11/02505 and AGL2010-22319-C03-03); Consejería de Salud de la Junta de Andalucía (PI0105/2007), and by the Generalitat Valenciana, Spain (ACOMP/2013/165 and ACOMP/2013/159)
Mecanismo de cambio de contexto de tareas en una arquitectura PowerPC
El estudio se centra en la implementación de un mecanismo de cambio de contexto rápido de tareas en un Scheduler Preemptive para la arquitectura PowerPC, ya que se utiliza ampliamente en el área automotriz, desde pequeños de control de un actuador o monitoreo de un sensor hasta el desarrollo de un módulo de gran procesamiento como lo es un BCM (Body Controller Module).Consejo Nacional de Ciencia y Tecnologí
Using Large Language Models for Interpreting Autonomous Robots Behaviors
The deployment of autonomous robots in various domains has raised significant
concerns about their trustworthiness and accountability. This study explores
the potential of Large Language Models (LLMs) in analyzing ROS 2 logs generated
by autonomous robots and proposes a framework for log analysis that categorizes
log files into different aspects. The study evaluates the performance of three
different language models in answering questions related to StartUp, Warning,
and PDDL logs. The results suggest that GPT 4, a transformer-based model,
outperforms other models, however, their verbosity is not enough to answer why
or how questions for all kinds of actors involved in the interaction
Prospective associations between a priori dietary patterns adherence and kidney function in an elderly Mediterranean population at high cardiovascular risk
Purpose To assess the association between three diferent a priori dietary patterns adherence (17-item energy reduced Mediterranean Diet (MedDiet), Trichopoulou-MedDiet and Dietary Approach to Stop Hypertension (DASH)), as well as
the Protein Diet Score and kidney function decline after one year of follow-up in elderly individuals with overweight/obesity
and metabolic syndrome (MetS).
Methods We prospectively analyzed 5675 participants (55–75 years) from the PREDIMED-Plus study. At baseline and at
one year, we evaluated the creatinine-based estimated glomerular fltration rate (eGFR) and food-frequency questionnaires derived dietary scores. Associations between four categories (decrease/maintenance and tertiles of increase) of each dietary
pattern and changes in eGFR (ml/min/1.73m2
) or≥10% eGFR decline were assessed by ftting multivariable linear or logistic
regression models, as appropriate.
Results Participants in the highest tertile of increase in 17-item erMedDiet Score showed higher upward changes in eGFR
(β: 1.87 ml/min/1.73m2
; 95% CI: 1.00–2.73) and had lower odds of≥10% eGFR decline (OR: 0.62; 95% CI: 0.47–0.82)
compared to individuals in the decrease/maintenance category, while Trichopoulou-MedDiet and DASH Scores were not
associated with any renal outcomes. Those in the highest tertile of increase in Protein Diet Score had greater downward
changes in eGFR (β: − 0.87 ml/min/1.73m2
; 95% CI: − 1.73 to − 0.01) and 32% higher odds of eGFR decline (OR: 1.32;
95% CI: 1.00–1.75).
Conclusions Among elderly individuals with overweight/obesity and MetS, only higher upward change in the 17-item
erMedDiet score adherence was associated with better kidney function after one year. However, increasing Protein Diet Score
appeared to have an adverse impact on kidney health. Trial Registration Number: ISRCTN89898870 (Data of registration:
2014)
Contribución al conocimiento de la flora de Andalucía: citas novedosas e interesantes de la provincia de Almería
Contribution to the knowledge about Andalusian flora: new and interesting cites of the Almería province.Palabras clave. Corología, Isla de Alborán, sureste ibérico, xenófitas.Key words. Corology, Alborán Island, South-Eastern Iberian Peninsula, xenophytes
Strategic management of virtual education for quality of learning in university students, Covid-19, Peru
The objective of this review article is to describe the strategic management that was given to virtual education in such a way as to guarantee a quality standard of learning for university students in times of pandemic. For this, through a bibliographic review, the state of the art of university management provided during the COVID-19 pandemic is reviewed, in which higher-level educational institutions through their respective administrative areas in union with the state they looked for ways to be able to resume academic activities that had to cease due to the confinement decreed by the Peruvian state, due to this, virtual education was chosen, a model that allowed continuing academic activities, however this led to various new challenges that had to be faced as the model was implemented. It is concluded that, although virtual education in its initial implementation caused various problems, thanks to the strategic management provided by the different universities hand in hand with the Peruvian state, it is possible to provide a quality education taking advantage of the multiple benefits that education offers. virtual
Academic Directors Facing Internet Addictions, Learning and Health Promotion
The result that is presented is expressed from a bibliographic review of works published during the last two years 2020-2022 and, through which it was possible to verify the relationships that are established between the work of the Academic Directors, before the latent challenge and visible that is the crossroads of Internet addictions, by university students, increased in the stage already overcome of social isolation imposed by Covid 19 but, with emphasis on the achievement of learning at this high educational level, its risks and consequent decreases in the attacks that occur as a result of procrastination. All associated with the addictive phenomenon, in a projection of health promotion that the current, humanistic, modern and developing university should not give up in any way, being precisely in this direction an unavoidable pillar of social development, which lies precisely in the high professional qualification. of the new generations committed to a prosperous and sustainable social change
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