Analysis and implementation of decimal arithmetic hardware in nanometer CMOS technology

Scope and Method of Study: In today's society, decimal arithmetic is growing considerably in importance given its relevance in financial and commercial applications. Decimal calculations on binary hardware significantly impact performance mainly because most systems utilize software to emulate decimal calculations. The introduction of dedicated decimal hardware on the other hand promises the ability to improve performance by two or three orders of magnitude. The founding blocks of binary arithmetic are studied and applied to the development of decimal arithmetic hardware. New findings are contrasted with existent implementations and validated through extensive simulation.Findings and Conclusions: New architectures and a significant study of decimal arithmetic was developed and implemented. The architectures proposed include an IEEE-754 current revision draft compliant floating-point comparator, a study on decimal division, partial product reduction schemes using decimal compressor trees and a final implementation of a decimal multiplier using advanced techniques for partial product generation. The results of each hardware implementation in nanometer technologies are weighed against existent propositions and show improvements upon area, delay, and power

Reflexión sobre políticas nacionales de educación en ciudadanía de Colombia frente a la necesidad de pedagogías reflexivas

El documento plantea un horizonte normativo para entender la ciudadanía y los procesos de educación frente al particular, remontándose a diferentes disciplinas y perspectivas que se recogen en un órgano común; a partir de lo cual se hace una revisión documental de diferentes políticas nacionales de educación relacionadas con la ciudadanía y se observa el alcance de los procesos pedagógicos en el país, evidenciando a su vez la debilidad en dinámicas de implementación que bien pueden ser investigadas y reflexionadas de cara a proponer nuevos caminos de educación ciudadana en Colombia.The document proposes a normative horizon to understand the citizenship and the processes of education before the individual, going back to different disciplines and perspectives that are collected in a common organ; from which a documentary review of different national education policies related to citizenship is made and the scope of the pedagogical processes in the country is observed, demonstrating in turn the weakness in implementation dynamics that can be well researched and reflected in order to propose new paths of citizen education in Colombia

Multi-frequency backhaul analysis for UABS in disaster situations

When a disaster occurs, the land-based cellular network could go offline for some days. Using an Unmanned Aerial Base Station (UABS) network is a promising solution to serve unconnected ground users. In this article, we propose a multifrequency backhaul architecture, which considers power and capacity constraints, to support the UABS network in a realistic 3D scenario in the city of Ghent, Belgium. Simulations results show that at the optimal flight height (80 m), up to 87% of the users could be supported using the multifrequency scenario compared with single frequency scenarios where coverage is about 70%

System assessment of WUSN using NB-IoT UAV-aided networks in potato crops

Unmanned Aerial Vehicles (UAV) are part of precision agriculture; also, their impact on fast deployable wireless communication is offering new solutions and systems never envisioned before such as collecting information from underground sensors by using low power Internet of Things (IoT) technologies. In this paper, we propose a (Narrow Band IoT) NB-IoT system for collecting underground soil parameters in potato crops using a UAV-aided network. To this end, a simulation tool implementing a gateway mounted on a UAV using NB-IoT based access network and LTE based backhaul network is developed. This tool evaluates the performance of a realistic scenario in a potato field near Bogota, Colombia, accounting for real size packets in a complete IoT application. While computing the wireless link quality, it allocates access and backhaul resources simultaneously based on the technologies used. We compare the performance of wireless underground sensors buried in dry and wet soils at four different depths. Results show that a single drone with 50 seconds of flight time could satisfy more than 2000 sensors deployed in a 20 hectares field, depending on the buried depth and soil characteristics. We found that an optimal flight altitude is located between 60 m and 80 m for buried sensors. Moreover, we establish that the water content reduces the maximum reachable buried depth from 70 cm in dry soils, down to 30 cm in wet ones. Besides, we found that in the proposed scenario, sensors & x2019; battery life could last up to 82 months for above ground sensors and 77 months for the deepest buried ones. Finally, we discuss the influence of the sensor & x2019;s density and buried depth, the flight service time and altitude in power-constrained conditions and we propose optimal configuration to improve system performance

Coexistence for LTE-advanced and FSS services in the 3.5GHz band in Colombia

The 3.5GHz band is an optimal candidate for 5G networks due to its propagation characteristics and massive bandwidth. However, services like the Fixed Satellite Service (FSS) are using this band in several countries. Therefore, this paper presents a coexistence study of the Long Term Evolution - Advanced (LTE-A) and FSS services in the 3500-3700 MHz in Colombia. Simulations were done in realistic scenarios in the city of Bogota, Colombia. Preliminary results show that critical scenarios are the ones from the LTE eNodeB (eNB) and Users Equipment (UE) nodes to the FSS earth stations. The study includes the analysis of Guard Bands (GB) and arrival angles into the Protection Distances (PD). Results show that the PD is highly dependent on the angle of the interfering signal and the GB used. The PD for a cochannel interference in a suburban scenario is higher than 250km, in the worst-case scenario, and could be reduced down to 17.5 km if a 25 MHz GB is included and the angular difference of the interfering LTE-A signal is 42 square. Moreover, our results show that the PD needed for interference from UE are 100 times less compared to the eNB ones

Diseño e implementacion de una propuesta pedagógica y de gestión para mejorar el aprendizaje del idioma ingles en Iso estudiantes de ingles I de corporación Universitaria Unitec

Este trabajo de investigación busca colaborar con una problemática evidenciada en la corporación universitaria Unitec, que es el constante aplazamiento por parte de los estudiantes en los niveles de Ingles que deben cursar. Esta investigación propone unas estrategias didácticas desde la gestión de aula que permitan a los estudiantes mejorar en su aprendizaje del inglés como lengua extrajera, redundando estas como parte principal en el programa de ingles I de la corporación universitaria Unitec.This research seeks to work with a problem evident in the university corporation Unitec, which is the constant postponement of students at levels that are required to take English. This research proposes some teaching strategies for classroom management that allow students to improve their learning of English as a foreign language, resulting such as principals in the English program of the university corporation I Unitec

Design and set up of a pulverized panela machine

The panela is a food well known in the world for its benefits to humans since provides energy necessary and essential nutrients for the development of the body's metabolic processes. This is obtained from sugar cane, and a substance-free ingredient that can affect health. While, in culinary and gastronomic arts sector is used as a sweetener. The process of obtaining the panela is developed by successive and prolonged boiling, which causes moisture loss and then concentrates and forms a tiny mass that when cooled solidifies into blocks. The research work carried out focuses on the static and dynamic analysis of the designed parts that allow various processes (whipped, sifted, and dried) for large-scale panela production, analyzes the behavior under different loads (mechanical stress, displacement, and thermal study) based on Finite Element Analysis (FEA) using SolidWorks and Comsol Multiphysics software. Clearly, is important to mention that an appropriate size for the mesh was considered along with Von Mises criteria to be compared with the elastic limit of the selected material for the definition of the final prototype which was designed following the Pahl and Beitz design methodology respectively. A modal analysis of the panela pulverized machine was performed to verify natural process frequencies and vibration modes. Also, a friendly HMI interface for the user was implemented considering the characterization of the users (workers, farmers) and the nature of the process (artisanal).The start-up of the panela pulverizing machine showed a dependence on the consistency and origin of the molasses, depending on this the capacity and size of the pulverized panela

Analysis of the denitrification pathway and greenhouse gases emissions in Bradyrhizobium sp. strains used as biofertilizers in South America

Aims Greenhouse gases are considered potential atmospheric pollutants, with agriculture being one of the main emission sources. The practice of inoculating soybean seeds with Bradyrhizobium sp. might contribute to nitrous oxide (N2O) emissions. We analyzed this capacity in five of the most used strains of Bradyrhizobium sp. in South America. Methods and Results We analyzed the denitrification pathway and N2O production by B. japonicum E109 and CPAC15, B. diazoefficiens CPAC7, and B. elkanii SEMIA 587 and SEMIA 5019, both in free‐living conditions and symbiosis with soybean. The in silico analysis indicated the absence of nosZ genes in B. japonicum and the presence of all denitrification genes in B. diazoefficiens strains, as well as the absence of nirK, norC and nosZ genes in B. elkanii. The in planta analysis confirmed the N2O production under saprophytic conditions or symbiosis with soybean roots nodules. In the last case up to 26·1 and 18·4 times higher in plants inoculated with SEMIA5019 and E109 respectively, than in those inoculated with USDA110. Conclusions The strains E109, SEMIA 5019, CPAC15 and SEMIA 587 showed the highest N2O production both as free‐living cells and in symbiotic conditions in comparison with USDA110 and CPAC7, which do have the nosZ gene. Although norC and nosZ could not be identified in silico or in vitro in SEMIA 587 and SEMIA 5019, these strains showed capacity to produce N2O in our experimental conditions. Significance and Impact of Study This is the first report to analyze and confirm the incomplete denitrification capacity and N2O production in four of the five most used strains of Bradyrhizobium sp. for soybean inoculation in South America.Fil: Obando Castellanos, Dolly Melissa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Correa-Galeote, David. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Castellano-Hinojosa, Antonio. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Gualpa, José Luis. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hidalgo, Alba. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: de Dios Alché, Juan. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Bedmar, Eulogio. Consejo Superior de Investigaciones Científicas. Estación Experimental del Zaidín; EspañaFil: Cassan, Fabricio Dario. Universidad Nacional de Rio Cuarto. Facultad de Cs.exactas Fisicoquimicas y Naturales. Instituto de Investigaciones Agrobiotecnologicas. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Cordoba. Instituto de Investigaciones Agrobiotecnologicas.; Argentin