Mitigation of Distortions in Radio-Over-Fiber Systems Using Machine Learning

Introducción: El constante crecimiento de usuarios conectados a internet por medio de dispositivos móviles ha conllevado a incrementar la investigación en el paradigma de las redes híbridas conocido como Radio-sobre-Fibra. Estas redes aprovechan las ventajas del ancho de banda de la fibra óptica y la movilidad de las transmisiones inalámbricas, evitando el cuello de botella que se da por la conversión óptico a eléctrico. No obstante, la dispersión cromática propia de la fibra óptica genera distorsiones en la señal de radiofrecuencia modulada ópticamente, lo cual limita su alcance.  Objetivo: Mejorar el desempeño de un sistema de radio sobre fibra en términos de la tasa de error de bit, usando demodulación no simétrica por medio del algoritmo de aprendizaje automático Máquina de Soporte Vectorial.  Metodología: Se simula un sistema de Radio-sobre-Fibra en el software especializado VPIDesignSuite. Se transmiten señales de radiofrecuencia moduladas en formatos 16 y 64-QAM con diferentes anchos de línea de láser sobre fibra óptica. Se aplica el algoritmo Máquina de Soporte Vectorial para la demodulación de la señal.  Resultados: La implementación del algoritmo de aprendizaje automático para la demodulación de la señal mejora significativamente el desempeño de la red permitiendo alcanzar los 30 km de transmisión por fibra óptica. Esto implica una reducción de la tasa de error de bit hasta en dos órdenes de magnitud en comparación con la demodulación tradicional.  Conclusiones: Se demuestra que con el uso de umbrales asimétricos usando algoritmo de Máquina de Soporte Vectorial se logran mitigar distorsiones en términos de la tasa de error de bit. Así, esta técnica se hace atractiva para futuras redes de acceso de alta capacidad.  Introduction: The ever-growing number of users connected to internet via mobile devices has driven to increase the research in the paradigm of hybrid optical networks called Radio-over-Fiber. These networks take advantages of the bandwidth given by the optical fiber and the mobility given by wireless transmissions, avoiding the bottleneck of optical-to-electrical conversion interfaces. However, the chromatic dispersion of the optical fiber generates distortions in the radiofrequency signals optically modulated, limiting the reach of transmission.  Objective: To improve the performance of a Radio-over-Fiber system in terms of bit-error-rate, using nonsymmetrical demodulation by means of the machine learning algorithm Support Vector Machine.  Methodology: A Radio-over-Fiber System is simulated in the specialized software VPIDesignSuite. The radiofrequency signals are modulated at 16 and 64-QAM formats with different laser linewidths and transmitted over optical fiber. The Support Vector Machine algorithm is applied to carry out nonsymmetrical demodulation.  Results: The implementation of the machine learning algorithm for signal demodulation significantly improves the network performance, reaching transmissions up to 30 km. It implies a reduction of the bit-error-rate up to two Introduction: The ever-growing number of users connected to internet via mobile devices has driven to increase the research in the paradigm of hybrid optical networks called Radio-over-Fiber. These networks take advantages of the bandwidth given by the optical fiber and the mobility given by wireless transmissions, avoiding the bottleneck of optical-to-electrical conversion interfaces. However, the chromatic dispersion of the optical fiber generates distortions in the radiofrequency signals optically modulated, limiting the reach of transmission.  Objective: To improve the performance of a Radio-over-Fiber system in terms of bit-error-rate, using nonsymmetrical demodulation by means of the machine learning algorithm Support Vector Machine.   Methodology: A Radio-over-Fiber System is simulated in the specialized software VPIDesignSuite. The radiofrequency signals are modulated at 16 and 64-QAM formats with different laser linewidths and transmitted over optical fiber. The Support Vector Machine algorithm is applied to carry out nonsymmetrical demodulation.  Results: The implementation of the machine learning algorithm for signal demodulation significantly improves the network performance, reaching transmissions up to 30 km. It implies a reduction of the bit-error-rate up to two orders of magnitude in comparison with conventional demodulation.  Conclusions: Mitigation of distortions in terms of bit-error-rate is demonstrated in a Radio-over-Fiber system using nonsymmetrical demodulation by using the Support Vector Machine algorithm. Thus, the proposed technique can be suitable for future high-capacity access networks. &nbsp

Managing and Deploying Distributed and Deep Neural Models Through Kafka-ML in the Cloud-to-Things Continuum

The Internet of Things (IoT) is constantly growing, generating an uninterrupted data stream pipeline to monitor physical world information. Hence, Artificial Intelligence (AI) continuously evolves, improving life quality and business and academic activities. Kafka-ML is an open-source framework that focuses on managing Machine Learning (ML) and AI pipelines through data streams in production scenarios. Consequently, it facilitates Deep Neural Network (DNN) deployments in real-world applications. However, this framework does not consider the distribution of DNN models on the Cloud-to-Things Continuum. Distributed DNN significantly reduces latency, allocating the computational and network load between different infrastructures. In this work, we have extended our Kafka-ML framework to support the management and deployment of Distributed DNN throughout the Cloud-to-Things Continuum. Moreover, we have considered the possibility of including early exits in the Cloud-to-Things layers to provide immediate responses upon predictions. We have evaluated these new features by adapting and deploying the DNN model AlexNet in three different Cloud-to-Things scenarios. Experiments demonstrate that Kafka-ML can significantly improve response time and throughput by distributing DNN models throughout the Cloud-to-Things Continuum, compared to a Cloud-only deployment.10.13039/501100004837-Spanish Projects “rFOG: Improving Latency and Reliability of Offloaded Computation to the FOG for Critical Services” (Grant Number: RT2018-099777-B-100). 10.13039/501100006461-“IntegraDos: Providing Real-Time Services for the Internet of Things through Cloud Sensor Integration” (Grant Number: PY20_00788). 10.13039/100009473-“Advanced Monitoring System Based on Deep Learning Services in Fog” (Grant Number: UMA18FEDERJA-215

Metodologia de adopcion de comercio electronico para las Pymes del pais.

129 p.De acuerdo a las necesidades actuales de búsqueda de herramientas que permitan a las empresas readecuarse al presente tecnológico, este proyecto plantea una metodología de adopción de Comercio electrónico enfocada a la pequeña y mediana empresa (Pymes), que es el sector que más requiere de métodos que le ayuden a utilizar de forma eficiente los recursos destinados al Comercio a través de Internet. En el estudio se pueden identificar tres actividades principales que se desarrollaron en forma paralela; éstas formaron la información base para el desarrollo de la metodología. La primera de estas tareas comprendió un análisis de las investigaciones de mercados que se han realizado a nivel nacional, cuyo objetivo fue identificar la percepción y la actitud de las Pymes con respecto al uso de Comercio electrónico. En forma paralela, se realizó un estudio de modelos de adopción de tecnologías, más específicamente modelos relacionados en referencia al Comercio electrónico, clasificándolos de acuerdo a las características más relevantes de éstos. Una tercera tarea comprendió un análisis de la situación actual respecto a la evolución del Comercio electrónico a nivel global y local, identificando factores de crecimientos y niveles de influencia en la estructura organizacional de las empresas. Las tres tareas anteriores ayudaron a identificar los principales parámetros, para discriminar entre los distintos modelos de adopción de tecnologías y sus componentes, así como también, generaron la información base para el desarrollo de la metodología. En las siguientes páginas, se encontrará con variada información de base teórica que respalda el diseño final de la metodología que se presenta en este documento, así como, información que permite obtener un acercamiento por parte de la Pyme al concepto Comercio electrónico. Así, se entenderá que la información que aquí presentada tiene un carácter teórico, dado que la finalidad será proponer una metodología de adopción de Comercio electrónico, que sea aplicable a futuro en la Pyme

Effects of the production of goods and services on latin american natural ecosystems

The following research has the purpose of analyzing the impact of the practices of production of goods and services on Latin American natural ecosystems. Thus, to denounce the exploitation techniques that involve the degradation of the resources that allow life. At the same time, we promote the production of merchandise together with operations of low impact and environmental recovery. In the Latin American case, we note the ecological damage that occurs when the State’s surveillance function is deregulated by allowing the predatory use of the environment. Thus, exercising environmental control goes through the political exercise of the communities. We identify assets that serve to diagnose the condition of the various ecological niches based on evaluating the relevance of the production procedures carried out in them. We advocate for the multiplication of technical regulations that favor life in conditions of dignity. It is a bibliographic investigation from the rationalist-deductive approach.La siguiente investigación tiene el propósito de analizar el impacto de las prácticas de producción de bienes y servicios sobre los ecosistemas naturales latinoamericanos. Así, denunciar las técnicas de explotación que involucran la degradación de los recursos que permiten la vida. A su vez, impulsamos la producción de mercancías junto con operaciones de bajo impacto y recuperación ambiental. En el caso latinoamericano advertimos las lesiones ecológicas que acontecen cuando se desregula la función de vigilancia del Estado al permitir la empleo depredador del medio ambiente. Así, ejercer control ambiental pasa por el ejercicio político de las comunidades. Identificamos haberes que sirven para diagnosticar la condición de los diversos nichos ecológicos en función de evaluar la pertinencia de los procedimientos productivos en ellas efectuados. Abogamos por la multiplicación de ordenamientos técnicos que favorezcan la vida en condiciones de dignidad. Es una investigación bibliográfica desde el enfoque racionalista-deductivo

Biological interactions and simulated climate change modulates the ecophysiological performance of Colobanthus quitensis in the Antarctic ecosystem

Most climate and environmental change models predict significant increases in temperature and precipitation by the end of the 21st Century, for which the current functional output of certain symbioses may also be altered. In this context we address the following questions: 1) How the expected changes in abiotic factors (temperature, and water) differentially affect the ecophysiological performance of the plant Colobanthus quitensis? and 2) Will this environmental change indirectly affect C. quitensis photochemical performance and biomass accumulation by modifying its association with fungal endophytes? Plants of C. quitensis from King George Island in the South Shetland archipelago (62°09′ S), and Lagotellerie Island in the Antarctic Peninsula (65°53′ S) were put under simulated abiotic conditions in growth chambers following predictive models of global climate change (GCC). The indirect effect of GCC on the interaction between C. quitensis and fungal endophytes was assessed in a field experiment carried out in the Antarctica, in which we eliminated endophytes under contemporary conditions and applied experimental watering to simulate increased precipitation input. We measured four proxies of plant performance. First, we found that warming (+W) significantly increased plant performance, however its effect tended to be less than watering (+W) and combined warming and watering (+T°+W). Second, the presence of fungal endophytes improved plant performance, and its effect was significantly decreased under experimental watering. Our results indicate that both biotic and abiotic factors affect ecophysiological performance, and the directions of these influences will change with climate change. Our findings provide valuable information that will help to predict future population spread and evolution through using ecological niche models under different climatic scenarios

Knowledge transfer and the challenges of engineering training in the face of globalization.

La transferencia de conocimiento es una máxima en la sociedad contemporánea. Ante este fenómeno, impulsado por la globalización neoliberal, se le impone a las instituciones de educación universitaria cambios radicales que apuntan a adecuar los planes de estudio a los requerimientos de la aldea global. La formación de ingenieros no puede situarse al margen de estas perspectivas curriculares, pero ha de imponer una visión humanista al quehacer científico y tecnológico. El presente trabajo se inscribe en la ruta de fortalecer la ética y la crítica en la formación de ingenieros.Knowledge transfer is a maximum in contemporary society. Faced with this phenomenon, driven by neoliberal globalization, university education institutions are required to make radical changes that aim to adapt the study plans, according to the requirements of the ‘global village’. The training of engineers cannot be placed outside of these curricular perspectives, but it must impose a humanistic vision on scientific and technological work. This work is part of the route to strengthen ethics and criticism in the training of engineers

Ludovico Silva: Ideology and Education

The purpose of this research is to analyze in the work of Ludovico Silva his contributions on the theme of ideology and its link to education, from a hermeneutical perspective that seeks to interpret circumstantially the reflections of this Venezuelan socialist intellectual of the late twentieth century. A criticism of all ideology is revealed in his texts for becoming a justification of social relations that dehumanize, for which he promotes the cultivation of critical consciousness through education away from dogmas.La presente investigación tiene como propósito analizar en la obra de Ludovico Silva sus aportes en torno al tema de la ideología y su vinculación a la educación, desde una perspectiva hermenéutica que procura interpretar circunstancialmente las reflexiones de este intelectual socialista venezolano de finales de siglo XX. Se devela en sus textos una crítica a toda ideología por devenir en justificación de relaciones sociales que deshumanizan, por lo que promueve el cultivo de la conciencia crítica a través de la educación alejada de dogmas

Identificación de las áreas aptas para la agricultura extensiva en el municipio del Espinal-Tolima

En la escuela de ciencias agrícolas, pecuarias y del medio ambiente, en el programa de agronomía de la universidad nacional abierta y a distancia UNAD en ejecución con el diplomado de sistemas de información geográfica para el ordenamiento agroambiental del territorio, se realizó varias actividades para el modelamiento y desarrollo territorial de tipo agrícola, ambiental y climático, empleando el análisis de datos y técnicas de modelamiento para proyectar un mapa con una finalidad que es el análisis de varios aspectos técnicos como las coberturas del territorio, la proyección geográfica,atributos. Recopilando a la información necesaria y empleando las herramientas que senecesitan para el diseño de un modelo de datos preciso y que se pueda interpretar, con la finalidad de identificar esas áreas que sean aptas para la agricultura extensiva ya que es una de las principales fuentes de trabajo y economía del municipio del Espinal.In the school of agricultural, livestock and environmental sciences, in the agronomy program of the national open and distance university UNAD in execution with the diploma in geographic information systems for the agro-environmental planning of the territory, several activities were carried out for modeling and territorial development of an agricultural, environmental and climatic type, using data analysis and modeling techniques to project a map with a purpose that is the analysis of various technical aspects such as territory coverage, geographic projection, attributes. Gathering the necessary information and using the tools needed to design an accurate and interpretable data model, with the aim of identifying those areas that are suitable for extensive agriculture since it is one of the main sources of work. and economy of the municipality of Espinal

Design and construction of tank-chassis and lifting structure for centrifugal pump HL260 M powered by a Diesel Engine

This article deals with the design, simulation and construction of a fuel storage tank-chassis and a lifting system coupled as a single unit to a Cummins QSK19 engine driven HL260m pump that can guarantee an operating autonomy of up to 12 continuous hours and can be transported to different locations by means of lifting systems. For the mechanical design the recommendations of the American Institute of Steel Construction (AISC) and the application of the failure criteria for Von Mises ductile materials or Maximum Energy Distortion were used. For the dimensioning of the storage tank, the average consumption stipulated by the manufacturer was used and the simulations were performed with SolidWorks®. A functional and safe system that can be used in on-site applications was achieved

Prevalence of Diabetes Mellitus and Its Associated Unfavorable Outcomes in Patients With Acute Respiratory Syndromes Due to Coronaviruses Infection: A Systematic Review and Meta-Analysis

Introduction: Only 3 types of coronavirus cause aggressive respiratory disease in humans (MERS-Cov, SARS-Cov-1, and SARS-Cov-2). It has been reported higher infection rates and severe manifestations (ICU admission, need for mechanical ventilation, and death) in patients with comorbidities such as diabetes mellitus (DM). For this reason, this study aimed to determine the prevalence of diabetes comorbidity and its associated unfavorable health outcomes in patients with acute respiratory syndromes for coronavirus disease according to virus types. Methods: Systematic review of literature in Pubmed/Medline, Scopus, Web of Science, Cochrane, and Scielo until April of 2020. We included cohort and cross-sectional studies with no restriction by language or geographical zone. The selection and extraction were undertaken by 2 reviewers, independently. The study quality was evaluated with Loney’s instrument and data were synthesized by random effects model meta-analysis. The heterogeneity was quantified using an I2 statistic. Funnel plot, Egger, and Begg tests were used to evaluate publication biases, and subgroups and sensitivity analyses were performed. Finally, we used the GRADE approach to assess the evidence certainty (PROSPERO: CRD42020178049). Results: We conducted the pooled analysis of 28 studies (n = 5960). The prevalence analysis according to virus type were 451.9 diabetes cases per 1000 infected patients (95% CI: 356.74-548.78; I2 = 89.71%) in MERS-Cov; 90.38 per 1000 (95% CI: 67.17-118.38) in SARS-Cov-1; and 100.42 per 1000 (95% CI: 77.85, 125.26 I2 = 67.94%) in SARS-Cov-2. The mortality rate were 36%, 6%, 10% and for MERS-Cov, SARS-Cov-1, and SARS-Cov-2, respectively. Due to the high risk of bias (75% of studies had very low quality), high heterogeneity (I2 higher than 60%), and publication bias (for MERS-Cov studies), we down rate the certainty to very low. Conclusion: The prevalence of DM in patients with acute respiratory syndrome due to coronaviruses is high, predominantly with MERS-Cov infection. The unfavorable health outcomes are frequent in this subset of patients. Well-powered and population-based studies are needed, including detailed DM clinical profile (such as glycemic control, DM complications, and treatment regimens), comorbidities, and SARS-Cov-2 evolution to reevaluate the worldwide prevalence of this comorbidity and to typify clinical phenotypes with differential risk within the subpopulation of DM patients.Revisión por pare