158 research outputs found

    Spatial and temporal analysis of the seasonal and interannual variability in the tropical Pacific simulated with a coupled GCM

    Get PDF
    In the first part of this work, the dominant time scales that explain the tropical variability of the first SINTEX simulation (ECHAM4(T30)-ORCA) are identified through a spectral analysis. Higher order spectral analysis is used to examine the interactions among these time scales. The time series analyzed are an average of sea surface temperature over the Niño3 region. The time scales obtained are compared with those identified in another coupled GCM simulation (ECHAM4(T42)-OPYC3). The higher importance of the biannual time scale in this last is explained partly by the strength of the coupling between the annual and the biannual time scales. There is no such strong coupling in the SINTEX simulation. Important differences among the generation of the simulated warm (or cold) event suggest the need of a systematic classification to isolate their relevant features. Therefore in the second part of this work, we address this problem. A space-time cluster analysis is performed on a data set built by collecting the values of the heat content anomalies in the tropical Pacific region, in the fifteen months previous to a peak in the Niño3 Index that has been identified as a ‘warm’ (or ‘cold’) event. In the case of the warm events, three types of generation schemes are found. In two of them, there are anomalies of heat content in the west, north and south of the equator, more than nine months before the events start. In the third case, the anomalies appear and grow in the central equatorial Pacific. Only two types are needed to classify the generation of cold events. Negative sea level height anomalies appear six months before the Niño3 Index reaches the (local) minimum. They are located north of the equator in one of the groups, and south of it in the other. Some of these characteristic traits also appear in observations of warm and cold events

    Scale interactions in the tropical Atlanticvariability simulated with a coupled GCM

    Get PDF
    Warm and cold events in the Gulf of Guinea are an important feature in the interannual variability of the tropical Atlantic Ocean, and partly a manifestation of the equatorial Atlantic system's intrinsic variability. Due to the relatively reduced zonal extension of this ocean, the latter variability is comparatively weak and thus strongly modified by other factors at play, either local or remote, like the seasonal cycle or ENSO. We present here an analysis of the tropical Atlantic variability in a 100-year-long chunk of the output of a coupled GCM. Through it, we obtain a better understanding of this variability and of its interactions with the seasonal cycle and with the ENSO signal. Following hints in the observations, we separate warm or cold events of the simulation in a few types, according to their similarities and differences. This classification is carried out as a spatio-temporal cluster analysis of the values, from nine months before up to the peak of the event, of the heat content anomalies. This is an optimal variable to monitor the generation of the events. One of the warm event classes can be explained by ENSO interactions. One of the cold event types can be explained by this influence as well, while the seasonal interactions might explain the characteristics of another of them

    Spatial and temporal analysis of the seasonal and interannual variability in the tropical Pacific simulated with a coupled GCM

    Get PDF
    In the first part of this work, the dominant time scales that explain the tropical variability of the first SINTEX simulation (ECHAM4(T30)-ORCA) are identified through a spectral analysis. Higher order spectral analysis is used to examine the interactions among these time scales. The time series analyzed are an average of sea surface temperature over the Niño3 region. The time scales obtained are compared with those identified in another coupled GCM simulation (ECHAM4(T42)-OPYC3). The higher importance of the biannual time scale in this last is explained partly by the strength of the coupling between the annual and the biannual time scales. There is no such strong coupling in the SINTEX simulation. Important differences among the generation of the simulated warm (or cold) event suggest the need of a systematic classification to isolate their relevant features. Therefore in the second part of this work, we address this problem. A space-time cluster analysis is performed on a data set built by collecting the values of the heat content anomalies in the tropical Pacific region, in the fifteen months previous to a peak in the Niño3 Index that has been identified as a ‘warm’ (or ‘cold’) event. In the case of the warm events, three types of generation schemes are found. In two of them, there are anomalies of heat content in the west, north and south of the equator, more than nine months before the events start. In the third case, the anomalies appear and grow in the central equatorial Pacific. Only two types are needed to classify the generation of cold events. Negative sea level height anomalies appear six months before the Niño3 Index reaches the (local) minimum. They are located north of the equator in one of the groups, and south of it in the other. Some of these characteristic traits also appear in observations of warm and cold events

    Implementation of AMI Systems in CFE-Distribution, Mexico

    Get PDF
    The Smart Grid concept has been conceived as the integration of the electrical grid (generation, transmission and distribution) and the communications network of an electric utility. Although, traditional communications interfaces, protocols and standards has been used in the electrical grid in an isolated manner, modern communications networks are considered as the fundamental enabling technologies within a Smart Grid environment. Emerging communications technologies, protocol architectures and standards can help to build a common communications network infrastructure for data transport between customer premises, power substations, power distribution systems, utility control centers and utility data centers. The Smart Grid will support traditional applications such as supervisory control and data acquisition (SCADA), distribution automation (DA), energy management systems (EMS), demand site management (DSM) and automated meter reading (AMR), etc., as well as new applications like advanced metering infrastructure (AMI), substation automation (SA), microgrids, distributed generation (DG), grid monitoring and control, data storage and analysis, among others. To make this possible, the Smart Grid requires a two-way wide area communications network between different dispersed areas, from generation to consumer premises. An AMI system uses communication technologies for smart meter reading several times a day to get data consumption of electricity, as well as sending outage alarm information and meter tampering almost in real time, from the meter to the control center. Currently, there are various communication technologies to implement AMI systems. This paper presents an overview of the most relevant communications technologies that can be used to implement AMI communications infrastructure such as neighborhood area networks (NAN), field area networks (FAN) and wide area networks (WAN) using different transmission media such as fiber optics, spread spectrum radio frequency, microwave, WiMax, Wi-Fi, ZigBee, cellular, and power line carrier. In addition, a review of the current state of various AMI projects around the world, including the progress in the implementation of AMI systems in Mexico, besides the evaluation performance of CFE´s AMI networks

    Caracterización y cuantificación de los productos de oxidación del colesterol de la grasa intramuscular del lomo de cerdo (fresco y adobado) con diferentes irradiaciones y empaquetados durante el almacenamiento

    Get PDF
    A study of the effect of E-beam (1 and 2 kGy) on the cholesterol oxidation product (COP) composition of fresh and marinated pork loin stored at 4 and 8 °C under different atmospheres (air, vacuum and carbon dioxide enriched ) has been carried out for the first time. The combined statistical treatment of the distinct variables showed that minor differences were found in some cholesterol oxidation products of fresh loin due to storage temperature, packaging method and storage time. No effect of irradiation (up to 2 KGy) on the COP amount was found, concluding that E-beam can be a useful tool to extend the shelf-life of fresh and marinated loin without changes in the COP fraction.Se ha realizado un estudio sobre el efecto de la radiación de electrones (E-beam) (1 y 2 kGy) sobre los compuestos de oxidación del colesterol (COPs) del lomo de cerdo almacenado a 4 y 8 °C bajo diferentes atmósferas (aire, vacío y dióxido de carbono). Este tipo de estudio ha sido llevado a cabo por primera vez en este tipo de muestras. El tratamiento estadístico combinado de distintas variables muestra que se producen cambios menores en algunos COPs en el lomo fresco debido a la temperatura de almacenamiento al método de empaquetado y al tiempo de almacenamiento. No hubo efecto de la dosis de radiación (hasta 2 KGy) en los COPs, por lo que la radiación E-beam puede ser una herramienta útil para prolongar la vida útil del lomo fresco y adobado sin producir cambios en la composición de los COPs

    Technical Efficiency of Dairy Farms in Sierra Andina Using Neural Network Modeling

    Get PDF
    The aim of this paper was to estimate the efficiency of milk production of 1 168 cases in Ecuadoran Sierra Sur Andina, with the implementation of a neural network model with multilayer perceptrons. These cases were collected from secondary samples provided by the Official Institute of National Statistics of Ecuador, in 2016. The variables chosen for the model were total milk production on the previous day (P), as dependent variable, and total cattle heads (CH), total laborers in the field (E), and total area attended by laborer (S), as independent variables. The data from individual cases and their impact on the dependent variable were used as the variable selection criteria. The average efficiency was 8.11%, from which the total efficient cases detected (>0.70) were 11 (0.9% of the sample). Later, the cases studied were classified into three groups, depending on the estimated efficiency: Group 1 (≤ 0.4 efficiency); Group 2 (>0.4-≤0.7 efficiency); and Group 3 (>0.7 efficiency). A comparison produced several statistical differences (P<0.01) for variables total milk production/year on the farm, total field laborers, farm size, total cows, total cattle heads, calvings, pregnant cows, and served cows.The aim of this paper was to estimate the efficiency of milk production of 1 168 cases in Ecuadoran Sierra Sur Andina, with the implementation of a neural network model with multilayer perceptrons. These cases were collected from secondary samples provided by the Official Institute of National Statistics of Ecuador, in 2016. The variables chosen for the model were total milk production on the previous day (P), as dependent variable, and total cattle heads (CH), total laborers in the field (E), and total area attended by laborer (S), as independent variables. The data from individual cases and their impact on the dependent variable were used as the variable selection criteria. The average efficiency was 8.11%, from which the total efficient cases detected (>0.70) were 11 (0.9% of the sample). Later, the cases studied were classified into three groups, depending on the estimated efficiency: Group 1 (≤ 0.4 efficiency); Group 2 (>0.4-≤0.7 efficiency); and Group 3 (>0.7 efficiency). A comparison produced several statistical differences (P<0.01) for variables total milk production/year on the farm, total field laborers, farm size, total cows, total cattle heads, calvings, pregnant cows, and served cows

    Empatía en estudiantes de medicina de la universidad del norte, Colombia. Comparación de dos grupos (2012 y 2015)

    Get PDF
    Indexación: Scopus.Introduction: Empathy is an important component of the doctor-patient relationship, so the provision of empathy training to medical students must be a permanent goal of MD programs. Objective: To determine whether the academic medical empathy training activities implemented at Universidad del Norte in 2013 resulted in significant changes in medical students enrolled in 2015 compared to those enrolled in 2012. Materials and methods: Cross-sectional study conducted on 934 medical students (426 men and 508 women) enrolled at Universidad del Norte in 2015 who were administered the Spanish version of the Jefferson Scale of Empathy. The comparison group consisted of 345 medical students (106 men and 239 women) enrolled in 2012 at the same university. An analysis of variance (ANOVA) was performed and differences between academic years and between genders were evaluated, as well as the interactions between these two factors. Results: Although, in general, there were no significant differences between both groups in the three dimensions that were evaluated (p>0.05), statistically significant differences were observed in questions 4, 17 and 20, which are part of the Perspective Taking dimen-sion, and in question 6, included in the Walking in Patient’s Shoes dimension (p<0.05), since scores medias were higher in the 2012 cohort. Conclusions: The empathy training activities implemented in the medical program did not produce significant changes. Therefore, it is necessary to assess and improve both the con-tents and the teaching-learning processes related to empathy training in the medical program offered at Universidad del Norte.https://revistas.unal.edu.co/index.php/revfacmed/article/view/7049

    Participación comunitaria y procesos de comunicación en la implementación de programas de reasentamiento de familias dentro del contexto del desarrollo urbano en Barranquilla (Colombia)

    Get PDF
    Planning processes of development and growth of the city of Barranquilla have required the relocation of the population living in areas of intervention actions. As part of the implementation of the New Management Plan Territorial (POT), the city plans to revitalize an area around the Magdalena River with a view to improving the quality of life of citizens and to increase competitiveness of the city. The revitalization project is known as project “La Loma “. Under the current Land Use Plan of Barranquilla (POT), the urban development project “La Loma” includes, among other activities, the transfer of a large number of people currently living in this area. For this reason, this article aims to review the current POT and documents from City Council and the Mayor’s office associated with the POT and “La Loma” project, in order to identify and analyze the component of community participation and communication related to the implementation of this project. The results of the documents revealed the presence of regulatory elements associated with community participation. The results also showed potentially useful spaces for the implementation of inclusive communication processes. Therefore, this article proposes a guide for the formulation of a strategic communication plan with a focus on participatory communication and dialogue facilitator to be used during the execution of urban projects that include the relocation of families. © 2016, Universidad del Norte. All rights reserved
    corecore