Reconfiguration Algorithm to Reduce Power Losses in Offshore HVDC Transmission Lines

The race to increase the efficiency and reduce the power losses in transmission systems has resulted in the substantial growth of high-voltage direct current (HVDC) transmission systems. Moreover, the interconnection of these transmission systems significantly increases their reliability. However, the control of these meshed grids is a key problem that usually is managed through the control of the VSCs in those grids, but the control of the VSC can be complemented with a reconfiguration algorithm. This paper proposes the use of the particle swarm optimization algorithm, in order to reconfigure meshed HVDC transmission systems and reduce losses. The proposed algorithm has been tested in the CIGRE benchmark grid, which comprises of several offshore wind farms that generate energy sent to the grid through several HVDC transmission lines. The results show that as the energy generation changes due to wind changes, the grid topology must be reconfigured in order to achieve the maximum efficiency. Doing this reconfiguration, power savings around 18–19% could be achieve

Population Interest in Information on Obesity, Nutrition, and Occupational Health and Its Relationship with the Prevalence of Obesity: An Infodemiological Study

Objective: To identify and analyze population interest in obesity, nutrition, and occupational health and safety and its relationship with the worldwide prevalence of obesity through information search trends. Method: In this ecological study, data were obtained through online access to Google Trends using the topics "obesity", "nutrition", and "occupational health and safety". Obesity data were obtained from the World Health Organization (WHO) website for crude adult prevalence and estimates by region. The variables studied were relative search volume (RSV), temporal evolution, milestone, trend, and seasonality. The temporal evolution of the search trends was examined by regression analysis (R2). To assess the relationship between quantitative variables, the Spearman correlation coefficient (Rho) was used. Seasonality was verified using the augmented Dickey-Fuller (ADF) test. Results: The RSV trends were as follows: obesity (R2 = 0.04, p = 0.004); nutrition (R2 = 0.42, p < 0.001); and occupational health and safety (R2 = 0.45, p < 0.001). The analysis of seasonality showed the absence of a temporal pattern (p < 0.05 for all terms). The associations between world obesity prevalence (WOP) and the different RSVs were as follows: WOP versus RSV obesity, Rho = -0.79, p = 0.003; WOP versus RSV nutrition, Rho = 0.57, p = 0.044; and WOP versus RSV occupational health and safety, Rho = -0.93, p = 0.001. Conclusions: Population interest in obesity continues to be a trend in countries with the highest prevalence, although there are clear signs popularity loss in favor of searches focused on possible solutions and treatments, with a notable increase in searches related to nutrition and diet. Despite the fact that most people spend a large part of their time in the workplace and that interventions including various strategies have been shown to be useful in combating overweight and obesity, there has been a decrease in the population's interest in information related to obesity in the workplace. This information can be used as a guide for public health approaches to obesity and its relationship to nutrition and a healthy diet, approaches that are of equal utility and applicability in occupational health.S

Selection of CSI-based precoding techniques in the HF channel

Multi-carrier modulations are widely employed in ionospheric communications to mitigate the adverse effects of the HF channel. In this paper we show how performance achieved by these modulations can be further increased by means of CSIbased precoding techniques in the context of our research on interactive digital voice communications. Depending on communication constraints and channel parameters, we will show which of the studied modulations and precoding techniques to select so that to maximise performance

Influence of Nutrition, Food and Diet-Related Interventions in the Workplace: A Meta-Analysis with Meta-Regression

Objective: To review the scientific literature on the influence of verified nutrition, food and diet interventions on occupational health. Method: This study involved a critical analysis of articles retrieved from MEDLINE (via PubMed), Embase, Cochrane Library, PsycINFO, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature (LILACS) and Medicina en Español (MEDES) using the descriptors “Diet, Food, and Nutrition” and “Occupational Health” and applying the filters “Clinical Trial”, “Humans” and “Adult: 19+ years”; the search was conducted on 29 May 2021. Results: A total of 401 references were retrieved from the bibliographic databases, with an additional 16 identified through a secondary search; among the studies retrieved, 34 clinical trials were selected after applying the inclusion and exclusion criteria. The interventions were grouped into seven categories: (1) dietary interventions associated with exercise or educational programs; (2) individual environmental interventions or other educational actions; (3) educational interventions oriented toward lifestyle, dietetics, physical activity and stress management; (4) economic incentives; (5) multicomponent interventions (combination of mindfulness, e-coaching and the addition of fruits and vegetables); or dietary interventions (facilitating greater food supply in cafeterias); or interventions focused on physical exercise. Conclusions: Given that most people spend a large part of their time in the workplace and, therefore, eat at least one of their daily meals there, well-planned interventions—preferably including several strategies—have been demonstrated, in general, as useful for combating overweight and obesity. From the meta-regression study, it was observed that the interventions give better results in people who presented high Body Mass Index (BMI) values (obesity). In contrast, intervention 2 (interventions related to workplace environment) would not give the expected results (it would increase the BMI)

Optimization of Arq Parameters of Stanag 5066 for the HFDVL Modem

The reliability of bidirectional communication link can be guaranteed with Automatic Repeat Request Procedures (ARQ). The standard STANAG 5066 describes the ARQ procedure for HF communications that can either be applied to existing HF physical layers modems or adapted to future physical layer designs. In this contribution the physical layer parameters of an HF modem (HFDVL), developed by the authors over the last decade, are chosen to optimize the performance of the ARQ procedure described in STANAG 5066. Besides the interleaving length, constellation size and coding type, the OFDM-based HFDVL modem permits the selection of the number of receiver antennas. It will be shown that this parameter gives additional degrees of freedom and permits reliable communication over low SNR HF communication links

Dime de dónde vienes y te diré qué recibes. Un abordaje multidimensional de la movilidad social. CABA 2012-2013

Production of INCASI Project H2020-MSCA-RISE-2015 GA 69100

Aproximaciones a la imputación de ingresos desde los estudios de análisis de clase. Una propuesta a partir del uso de técnicas de análisis factorial

Production of INCASI Project H2020-MSCA-RISE-2015 GA 691004El propósito del trabajo es analizar las implicancias de la utilización de distintos métodos de imputación de datos en relación a la variable sobre ingresos. En particular, interesa describir y aplicar diferentes métodos y dar cuenta de las similitudes y diferencias entre ellos. De esta manera, se espera contribuir a la problemática de la falta de respuesta por parte de los informantes a las preguntas sobre ingresos de las encuestas. Específicamente, se parte del análisis de la estructura de clases, por lo cual, se consideran los siguientes métodos de imputación: por un lado, la asignación de la mediana de ingresos de la clase social a la que pertenece el encuestado y por el otro, la técnica multivariada de análisis de correspondencias múltiples. Ésta última permite observar la distribución y ubicación en el "espacio social multivariado" de aquellas unidades de análisis sin información sobre ingresos en relación a diversas dimensiones tales como la clase social, el nivel educativo, el consumo, la zona de residencia y también en relación al ingreso declarado por los restantes informantes. Se utilizará como fuente de información la encuesta "Movilidad social y opiniones sobre la sociedad actual" realizada entre 2012 y 2013 en la Ciudad Autónoma de Buenos Aires, llevada a cabo por el grupo de estudios sobre "Desigualdad y movilidad social", del Instituto de Investigaciones Gino Germani, Universidad de Buenos Aires

¿Quiénes y cómo se mueven en la estructura social? : análisis de la movilidad absoluta y relativa en la CABA

Production of INCASI Project H2020-MSCA-RISE-2015 GA 69100

Approaches to imputation of income from the perspective of class analysis. A proposal using factor analysis techniques

RC55 Social Indicators Imputation and Social Indicators: The Use of Factor Analysis for Imputing Missing DataBackground of INCASI Project H2020-MSCA-RISE-2015 GA 691004. WP1: CompilationThe purpose of the paper is to analyze the implications of using different methods to imput missing income data from the perspective of structure and class analysis. In particular, the interest is to describe and apply different methods and to examine the similarities and differences between them. In this way, it is expected to contribute to the problem of the lack of response in questions about income in household survey