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Introduction-- In Colombia, periods of intense rainfall are frequently associated with landslides. Since these processes are one of the phenomena that cause the most economic losses worldwide, it is necessary to study and model rainfall to establish its relationship with instability, using GIS tools and specialized software for this purpose. Objective-- Model the precipitation corresponding to the period from 2010 to 2019, for the municipality of Santa María in the department of Boyacá, in order to determine the effect of rainfall as a trigger of the mass movements presented during that time. The object of the study focused on the generation of the hydrological model of rainfall between the years 2010-2019, for the municipality of Santa María, to determine the effect of rain as a trigger for the mass movements presented during that time. Methodology-- Rainfall can facilitate the displacement of material, either by reducing resistance or increasing pore pressure. This paper presents a rainfall model developed from GIS tools, a quantitative multitemporal analysis and a probabilistic distribution method of the precipitation triggering factor, to determine periods of exceedance and non-exceedance of the rainfall threshold. Results-- From the rainfall models for the period 2010-2019 and their correlation with the mass movement inventory, the relationship between the rainfall trigger and landslides could be evidenced. Conclusions-- It is evident within the study area the incidence of precipitation and climatic factors in the increased possibility of occurrence of landslides. The model generated can be an input for the generation of the hazard map and municipal risk management. [ABSTRACT FROM AUTHOR]

Introduction: This paper introduces the design and the construction of an electromechanical slider that allows obtaining the instantaneous speed and acceleration of a platform that holds a scientific camera to take photos for the study motion-blurred images. The mechanical and electrical design requirements are given based on the conditions of presentation of the phenomenon. The system was calibrated concerning a standard instrument for the estimation of the uncertainty and error. Objective: the design, the making, and the calibration of an electromechanical slider system for the study of motion-blurred images. Objective: In this paper, the design, construction and calibration of an electromechanical system for the study of images with uniform motion blur is presented. Method: The development of the system is split into the following steps: the design and construction of an aluminum electromechanical slider built with a mobile platform that moves at constant speed, the calibration of the speed of the mobile platform using the Guide to Estimate Uncertainty in the Measurement, the design and construction of the electromechanical aluminum slider mounted with a mobile platform at constant acceleration and the calibration of the mobile platform for the acceleration applying the Guide for Estimation of Measurement Uncertainty. Results: Maximum uncertainties of 0,031 푚/푠 were obtained for speed and 0,029 푚/푠2 for acceleration of the system. Conclusions: The developed system corresponds to an electromechanical system that allows to move a cart along a pair of parallel bars, of low uncertainty with the possibility of measuring instantaneous speed and acceleration for the study of motion blurred images and teaching of motion physics. [ABSTRACT FROM AUTHOR]

Introduction--An Unmanned Aircraft UAV or UAVS, for its acronym in English, is one capable of performing a flight without the need for a pilot on board. The control techniques applied in unmanned aircraft systems are used to improve the performance and stability of these systems. Several control techniques have been created to automate systems, aiming to improve the performance of these looking for optimal performance conditions. Quadrotors are a type of unmanned aerial vehicle that is currently used due to its ease of Vertical Take-Off and Landing (VTOL), it is an ideal system to apply control laws because of its non-linearity and its unstable behavior in the face of external disturbances, usually environmental variables. Objective--Establish the advantages of the implementation of a robust control based on linear matrix inequalities, compared to a state feedback controller implemented in a quadrotor type unmanned aerial vehicle. Methodology--Two linear control strategies were designed and implemented: control by location of poles and zeros, and control based on Linear Matrix Inequalities LMI; therefore, in this work a linear model of the quadrotor represented in state variables was used. Results--The controllers are stable against external disturbances and disturbances caused by the environment. For the Pitch and Roll angles, the set point was adjusted to 0 degrees, and for the yaw angle, the set point was adjusted to 100 degrees. This paper shows the performance of the control strategy based on LMIs, short response times and maintains an equilibrium point between -2 and 2 degrees on each axis, allowing the quadrotor to stabilize at each angle of rotation. Conclusions--The controller based on LMIs has multiple advantages compared to the state feedback control strategy, since it allows the inclusion of several controller design criteria such as: the control input, the poles location, the definition of the infinite H norm, uncertainties, and disturbances. In addition, the LMIbased controller is presented as a solution to be implemented in a real system as it significantly improved the maximum overshoot, the response to external disturbances, the response time and quadrotor stabilization in the tests carried out. [ABSTRACT FROM AUTHOR]

Introduction-- In recent years, researchers have been evaluating the potential use of a wide range of raw materials in the production of geopolymers. This paper reports the convenience of using a natural puzzolan of pumice type from Paipa (Colombia) as a substitute material for cement (100% puzzolan) in the production of geopolymeric mortars. Objective-- The objective of this research focuses on the use of pumice stone as raw material in the production of geopolymeric cements in order to establish its mechanical behavior and durability. Method-- Type I Portland cement, natural puzzolan and sand were used as starting materials in the preparation of geopolymeric mortars from the alkaline activation of natural puzzolan. The geopolymeric mortars were prepared and tested according to the standards of the Colombian Institute of Technical Standards and the National Institute of Roads. Results-- The tests in geopolymers offer encouraging results and show a good potential in the preparation of cement with puzzolan exhibiting an adequate durability and resistance to relatively high compression at 28 days to be accepted in the development of new cementitious materials. Conclusions-- The use of natural puzzolan in the production of geopolymers becomes important for its role in the durability of the mortar under extreme and aggressive environmental conditions. [ABSTRACT FROM AUTHOR]

Introduction-- A mathematical model for flexible electrical loads and energy storage system scheduling is presented in this paper, leveraged by the hourly rates according to resolution CREG 015/2018 and analyzed at the residential sector in the context of new demand curves resulting from measures against the COVID-19 pandemic. Objectives-- Three mathematical optimization models are proposed, aiming to find the lowest billing cost for the end-user through flexible load characteristics and seeking optimization through mixed-integer linear programming models. Methodology-- For the calculation of hourly rates, the mathematical formulation described in resolution CREG 015 is implemented and hourly rates are obtained in three different levels following a logic similar to the demand response schemes called Time of Use. Results-- The results obtained show that a demand response program with hourly rates effectively introduces an economic incentive during the evaluated period, through the possibility of modifying consumption patterns that reduce the payment of the electricity bill. Conclusions-- The proposed model of energy demand through scheduling selected flexible loads model and the opportunity to use the energy stored in electric vehicles generates economic benefits for the user by minimizing the cost of energy during the teleworking period in COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Introduction- This paper presents the results of a research project. The objective was the creation of a model and simulation of the cocoa production chain in Colombia. It was funded by the Universidad Nacional Abierta y a Distancia. Objective- The purpose of this paper is to present a simulation model of the cocoa production chain in Colombia. Methodology- For the approach to this research, authors such as Absalón Machado --who offers a theoretical framework to present the understanding of agri-food systems--, were taken into account. A systemic perspective was also implemented for the research. In fact, it was modelled using system dynamics, which is based on the notion of feedback, delays in time, the idea of accumulation and reason for change, typical of differential and integral calculation. In this way, field work was carried out in terms of direct observation of international cocoa crops and processing plants. Results- A mathematical model that recreates the behavior of the cocoa production chain was obtained and was adjusted to the behavior of the chain for the time horizon studied. The model can be used to understand the dynamics of the chain as a whole based on the flows of information and material in the system. Conclusions- It is concluded that the use of system dynamic models, which represent a productive chain, can be used to promote decision-making processes based on simulated experimentation. This allows us to gain an understanding of the dynamics of the productive chain. Furthermore, it is evident that in situ perception of the phenomena to be modelled promotes a better representation of them. [ABSTRACT FROM AUTHOR]

Introduction- In recent years, the use of renewable energies and eco-friendly fuels has increased, among which one of the best performance is biodiesel, the paper shows an upgrade in the efficiency and effectiveness laboratory level's biodiesel obtaining. Objective-Evaluating the production of biodiesel employing ultrasound is presented, leading to improve the response time and efficiency of the reaction, concerning the conventional method using only temperature. Methodology-. In the transesterification process, castor oil, methanol, and potassium hydroxide are used, obtaining biodiesel and glycerin. A factorial design with two levels for transit time, mixing temperature, and ultrasound intensity were applied in an instrumented scale reactor to control these variables. Results- In the tests, values close to the reference stoichiometric value of the reaction were obtained. The statistic indicates a normal behavior of data, and identifies it as a factor of incidence in the efficiency of the reaction to the intensity of the ultrasound, concerning the response time of the reaction, the mixing temperature and the intensity of ultrasound. Conclusions- The efficiency of the reaction concerning the studied factors, it only depends on the ultrasound obtaining up to 95.7% of the stoichiometric value; and the response time of the reaction depends on the temperature and ultrasound, obtaining times of formation of product four times faster. [ABSTRACT FROM AUTHOR]

Introduction: There is a problem in the city of Barranquilla regarding the ignorance of the generation of used tires and their treatment at the end of their life cycle. This difficulty also occurs in Colombia, even globally. It is known that tire sales have a directly proportional relationship with the increase in the car fleet. Barranquilla shows a vehicle increase of 6% in 2015, 5% in 2016 and 4% in 2017. To date, the number of registered vehicles continues growing. As of December of 2018, the date on which this project is being carried on; there is no official system regulating the generation and proper disposal of used tires. While there are laws that oversee this issue, and preliminary projects that formulate systems for the proper collection and disposal of waste tires [1], most of them made in the capital city of Bogotá, are not duly reinforced by environmental authorities. Being the ignorance of generation is one of the main problems, a survey was applied to a sample of establishments that handle used tires in Barranquilla, where the existence of the problem was diagnosed and validated, and the number of used tires generated was estimated. Additionally, a forecast was made to analyze the behavior in later years. Following this, the most appropriate final disposal strategy for the treatment of this special solid waste was identified. Objective: analyze the current status of the generation, disposition and environmental effects of used tires in the city, focusing on the Riomar and Northern Historic Centre, as the field data on which the analysis is based on was collected there, due most concentration of establishments. This paper provides a starting point for an estimate of the used tires generated and forecasts the size of the environmental impact generated. Further, explores existing alternatives and processes for handling the disposed of used tires enabling the use of the materials and compounds within its structure for efficient uses of this resource while diminishing its impact on the environment. Method: Initially, 91 surveys were applied to establishments that handle used tires selected by sample size. The result of the study, whose consistency was verified through a Cronbach's Alpha analysis, shows in numbers the generation of weekly used tires at these active points. Then, the current factors that influence the generation of used tires are identified and expanded with a forecast for the generation of used tires in the next 5 years, covering the range of years from 2019 to 2023. Following the forecast, it will be in the foreground the existing methods for handling discarded tires, selecting the most appropriate by means of AHP method to contribute to the reduction of the environmental impact generated by improper disposal. Results: The results show that the problem of used tires is indisputable since most of these are eliminated in landfills. On the other hand, it's evident that there is a strong correlation between economic growth and registered vehicles. In the same way, the influence of the factors shows that there is a growing positive relationship between the registered vehicles and the number of used tires generated in the year. To give solution to the generation of used tires, it is found that the best final disposal strategy is the mechanical crushing of tires since, in addition to mitigating the environmental impact of the waste treatment, it also eliminates the possibility of contributing with pollutants. Conclusion: According to the results of the surveys and the forecasts made, it's evident that in 2023 the number of vehicles in Barranquilla will reach near that 231.918, which means an exponential growth in the generation of used tires; therefore, the importance of controlling the disposal of used tires is highlighted. Through the AHP methodology, it's established that the best practice to reduce or eliminate used tires is mechanical crushing due to its zero-carbon dioxide emission factor, and its products can be applied for rubber road asphalt and rubber coating for public playgrounds, among others. [ABSTRACT FROM AUTHOR]

Introduction- There is a great interest in reducing the use of fossil fuels due to the variation of prices and strong regulatory controls, which is why methods are being sought to reduce fuel consumption in internal combustion engines, such as the supply of products from the Hydrolysis of the water in the engine manifold. Objective- The objective of this paper is to present the results of an experimental methodology applied to estimate the mechanical and environmental performance of a vehicle fueled with gasoline and natural gas, when the engine is supplied with products resulting from the hydrolysis of water. Methodology- For the supply of said products to the vehicle, an external hydrolysis device was installed, and the vehicle has been instrumented with a fifth wheel, temperature and engine revolutions speed sensors, to perform acceleration tests on a flat road and a road with longitudinal slope angle. Additionally, torque and power tests with a chassis dynamometer, and pollutant emissions and fuel consumption tests were carried out. The tests were conducted in the outskirts of the city of Bogotá DC - Colombia, located at 2650 m above sea level. Results- The results show that the products of hydrolysis do not improve the mechanical performance of the vehicle, since they increase the time to arrive at the speeds defined in the acceleration tests up to 18% in the engine with gasoline and 7% in the engine with natural gas, and the torque and power are increase by around 1%. On the other hand, the results of the polluting emissions tests indicate that fuel consumption is reduced by about 7%. Conclusions- The results indicate that the performance of the vehicle does not improve, although fuel consumption decreases, the environmental performance does not decrease. [ABSTRACT FROM AUTHOR]

Given that transient overvoltage is a phenomenon that affects power systems, different methodologies to characterize this phenomenon in a practical and non-invasive way using its main features (peak value, duration and frequency of oscillation) are required. Therefore, the authors of this paper proposed an investigation project: the development of a prototype for the registration of these parameters in 11,4 kV networks using a capacitive electric field sensor, the initial stage for the research carried out for the above mentioned project was the state of the art regarding surges in medium voltage networks; then, the most important parameters of the surge that wanted to be studied and recorded were established. Afterwards, different options for the design of the electric field sensor were analyzed and, then, the detailed design, construction and testing of the prototype was carried out. This paper aims to present the methodology for measuring voltages in distribution networks 11.4 kV developed as part of the investigation previously outlined. Hence, the most important concepts and effects of the phenomenon, the methodology developed and the key findings of the investigation are presented. [ABSTRACT FROM AUTHOR]

Introduction- Early childhood is the pert of life that determines the development of the individual as a person. Undoubtedly, experiences influence the development of children. This paper analyzes the factors that have affected negatively the satisfaction index of the ICBF Community Welfare Homes users of the that work in favor of the infants, due to this, the SERVQUAL model emerges as a solution that allows the measurement of the quality of the service, to know the perceptions and expectations of the customers, and to identify the factors that affect the quality of the service. Objective- The purpose of this study is to determine the factors that affect the satisfaction of users in children's homes, through the application of a SERVQUAL model. Methodology- The article consists of 3 phases: Collection of information relevant to the case under study, Evaluation of the importance, expectation and perception of the user against the components of quality and Determination of quality components that affect user satisfaction. Results- The complete application of the statistical model was obtained, obtaining that the components "health and nutrition" are the ones that most affect the perception of the service quality, followed by the factors "Family community, pedagogical process and human talent" that also have an important index of incidence. Conclusions- The company is in continuous improvement, however, it is necessary to work responsibly to attend to the components that influence the perception of its service, to obtain a higher quality index. [ABSTRACT FROM AUTHOR]

Introduction- This paper sets forth the design and implementation of an anti-collision system for visually-impaired people using evolutionary artificial neural networks (EANNs). Objective- Present the implementation of evolutionary neural networks in a guide system for the visually-impaired people for the detection of static and moving obstacles. Methodology- The methodology is based on the creation of artificial neural networks from the cooperative co-evolutionary genetic algorithm (CCGA), which is responsible for structuring, modifying and training neural networks. It uses the network definition matrix (NDM). The NDM is based on a chromosome which is "part of the genetic algorithm". Once the NDM is generated, an artificial neural network is created in order to be trained. Results- The program accomplished several neural networks, generating 10 chromosomes in each execution. When the artificial neural networks were trained with the CCGA and the cooperation was included, the best anticollision neural networks were obtained considering a definite time. Hence, the anti-collision neural networks worked effectively for the detection of physical obstacles whether static or in motion. Conclusions- In this anti-collision system for the visually impaired, the effectiveness of neural networks used to provide a suitable answer when detecting both static and moving objects was observed, thus, delivering security to visually impaired people by avoiding them collisions with objects. [ABSTRACT FROM AUTHOR]

Introduction- This paper presents the study of the operational failure of a hydro-pneumatic system for the supply of water to a hospital facility. Objective- Determine the cause or causes for the interruption of the water supply of the hydro-pneumatic system to the building. Methodology- The hydraulic characteristic of the pipe system was drawn and compared with the hydraulic characteristic of the hydro-pneumatic system, verifying that it fully satisfied the load and flow requests demanded by the building. Given the presence of noises and vibrations in the suction pipe, the comparison of the required NPSH vs. the available NPSH determined that the current design of the suction pipe is the cause for the hydro-pneumatic system failure. Results- Three variants for the modification of the design of the suction pipe in order to eliminate the phenomenon of cavitation are proposed. This avoids putting into operation an auxiliary pump that increases energy consumption by 8,760 kWh/year with a cost of 1,839.6 $/year and the insecurity in the water service. Conclusions- The selected hydro-pneumatic equipment satisfactorily meets the requirements of the installation, except for the design of the suction pipe where the available NPSH is lower than the NPSH required at flow rates higher than 900 l/min, hence, producing the cavitation phenomenon and causing the output of system's service. [ABSTRACT FROM AUTHOR]

Introduction- This article is based on the interest of configuring tools to diagnose capacities and reference the needs and different criteria to integrate resources and routines so that Higher Education Institutions achieve systemic innovation objectives as a result of the strategic and operative management of capacities for the creation and dissemination of knowledge. For this reason, this article sets forth the approximation to a categorization model of innovation capacity indicators for Higher Education Institutions. It also concerns about its relationship with knowledge transfer processes based on the generation and classification of indicators regarding the resources and necessary routines in order to manage this transference. All this to influence business development from a knowledge management perspective. Objective- The purpose of this paper is to design a rubric model based on criteria and indicators in order to facilitate the evaluation of innovation capacities in Higher Education Institutions. Methodology- The development of the project used a documentary qualitative method of descriptive character in which the following phases were defined: Search for sources and bibliographic data to support the methodology developed; analysis of studies conducted by authors on measurement models and their results to weigh the indicators that were required to analyze the capacities proposed by the functional approach of innovation capabilities; and finally, ponder resources and routines to present a diagnostic scheme of innovation capabilities in two Higher Education Institutions. Results- The results lead to the analysis of innovation dynamics in Higher Education Institutions under a model of innovation capabilities. Conclusions- The identification and adequate management of innovation capabilities will allow obtaining the necessary competitive advantages for organizational sustainability, differentiation and strengthening of the university-company relationship. [ABSTRACT FROM AUTHOR]

Introduction- The use of composites made of vegetable origin materials has gained importance in some areas of engineering, mainly in civil construction. Objective- The objective of this paper is to analyze the physical and mechanical behavior of panels made with caña brava fibers and vegetal resin. Methodology- For the elaboration of the panels, the fibers were extracted using a mechanical crusher. The fibers were treated with a sodium hydroxide solution. The effect of the chemical treatment was evaluated by scanning electron microscopy. The roughness of the fibers was determined using the atomic force microscopy technique. For the manufacture of the composite, a compression method was used. The physical characterization of the panels was focused on the evaluation of the effective absorption, density, and percentage of swelling. To evaluate the mechanical behavior, static bending and mechanical fracture tests were performed. To evaluate the degradation of the material with the temperature, a thermogravimetric test was executed. Results- From the results, it is possible to verify that panels made with caña brava fibers and vegetal resin can present an increase in their dimensional stability when compared to panels made with Guadua Angustifolia Kunth fibers and show higher values of strength and stiffness than panels elaborated with coconut and bamboo fibers. Conclusions- Considering that caña brava is an invasive plant, its application as reinforcement of composite panels is a viable option to promote the development and application of new materials in civil construction. [ABSTRACT FROM AUTHOR]

Introduction- The use of unified power quality conditioners UPQC in the electric systems can correct waveform distortions in a steady state, like harmonics, flicker, and the power factor. Objective: This paper presents a novel approach for active compensation of overvoltage with a UPQC in dual topology or iUPQC. Methodology: The study it is presented in five stages, the section I shows an introduction and the state of the art, section II presents the unified power quality conditioner UPQC, section III describes the generalized reactive power theory applied to the iUPQC (dual topology), section IV shows the numerical simulations and the results and section V presents the conclusions of the study. Results: The results for the application of the iUPQC to the compensation of overvoltage are proved and compared with the more representative theory related to compensation of harmonics and low power factor. Conclusions: The control algorithm presented for the unified power quality conditioner in dual topology allows to compensate the overvoltage in threephase systems as well as voltage and current harmonics and the low power factor. [ABSTRACT FROM AUTHOR]

Introduction- The present article is aimed to present a brief introduction of the issues related to the low frequency vibrations, by indicating human walking as its relevant source which affecting structures of the footbridges and are turned into inconveniences to the pedestrian traffic. Objective: The main objective of this research paper is to explains the most common methods used by engineers for the evaluation of the vibrations and their effects as well as their limitations, furthermore a computer modeling technique was developed in order to approach it to the reality of the phenomenon of vibrations in pedestrian bridges. Methodology: The present work was divided into main phases: The first phase was a conceptual bibliographical review of the subject of floor vibrations by focusing on the use of the Design Guide No. 11 of the American Institute of Steel Constructions, with regard to the second phase it had to do with the developing of a computer model which included a definition of variables, the elaboration of a dynamic model of the structure, the calibration of the model, the evaluation of the parameters under study and the analysis of results and conclusions. Results: Consequently, and according to the preliminary stages, the results of the acceleration were obtained to different frequencies and to different degrees of damping by observing that the chosen sample was potentially susceptible between four and eight Hz ranges, hence when resonances took place the mentioned structure presented a peak acceleration above the threshold recommended by human beings comfort related to pedestrian bridges. Conclusions: To conclude it can be said that through the appropriate modeling techniques and finite elements convenient and reliable results should be accomplish that leading the design process of structures as pedestrian bridges. [ABSTRACT FROM AUTHOR]

This paper describes the development process and the results of a research project in which was made a purchase system through a mobile application based on NFC, incorporating an algorithm that implements the k–neighbors technique that allows the system to make personalized recommendations for each client. The development process includes the selection of technologies to be used, the design of the system's architecture, testing and detailed description of the design and implementation of the algorithm, based on the contrast between the different techniques used in recommender systems. Inferring that the design of the algorithm allows greater accuracy by including various important parameters for the business logic, such as the average rating of the users, visits, and purchases of each product. [ABSTRACT FROM AUTHOR]

It is known the contribution of SMEs in the economy as well as its management problems. One solution is the use of performance metrics in order to quantitatively understand their behavior. For this purpose, is really helpful the operations reference model (SCOR) designed by the Supply Chain Council. The research methodology of this paper presents a mixed approach with a non-experimental method, whose design is descriptive transversal. The aim is to define the different parts that make up the SCOR model for metalworking SMEs from Olavarria, Argentina, in order to identify the supply chain and category of each process, as well as define indicators and best practices for each conFig. tion. The sector has been divided into four subgroups and it was found that all of them work with design products, except of the manufacturing of aluminum apertures that also makes customized products and stock products [ABSTRACT FROM AUTHOR]

This paper shows a robust control strategy to address the inter-area oscillations in power systems using PSS's. The approach is based on the well-known Δω strategy of Kundur, and it was modified to take into account remote signals of the whole power system. The control center computes control signals for each generator in the system weighting the different measurements of each active generator. The robustness of the approach allows to face the communications delays due to remote measures. The strength of the proposed technique is validated through simulations over the Kundur two-areafour- machines test case power system, here it was used the complete model for the generators. The inter-area oscillations after a three-phase fault were successfully damped; also, the latencies which add instability in closed loop were faced. [ABSTRACT FROM AUTHOR]

This article classifies Spanish ports using a number of indicators that characterize the port activity. These indicators are treated with statistical analysis tools. Cluster analysis has been chosen to perform groupings among the selected ports. A methodology that covers all phases of research: environment, characterization, data source, cluster analysis, results and analysis of results has been followed in this paper. The results show that the Spanish ports are correctly characterized by physical and exploitation indicators, and that cluster analysis is a valid and useful tool for the port environment. [ABSTRACT FROM AUTHOR]

This paper studies the problem related to the variation of measured properties of a bituminous coal, fired in a Colombian electric power plant. The strategy was to implement a DOE methodology to find the causes of these variations, changing the storage conditions and relating it to the weather and different ways of handling the samples. The study contemplates the design, deployment and analysis of three experiments in order to trace the influence of such parameters as time and deplete of storage, weather evolution prior to consumption and some sampling procedures and in this way explain the divergence of coal properties between the reception inthe yards and its medium grinding just before firing. The results had shown that stocking time in yards and the automatic system´s performance, as the main cause of the problem. [ABSTRACT FROM AUTHOR]

Actually, transmission and interconnection systems have several vulnerabilities including the facility to analyze traffic that allows a high rate of attacks own IPv4 protocol, therefore it is necessary for services such as FTP, DHCP and SSH seek Migration and Deployment to IPv6 networks. It has characteristics of computer security by IPSEC protocol, regardless of the free operating system or own end customers. This paper analyzes by testing the functionality of the standard settings or IPv6 protocol and its security features in the implementation and setting in a controlled environment to mitigate attacks on authentication, integrity and confidentiality of information, allowing to determine which scenario services analyzed guarantee a higher level of own native IPSEC reliability through regardless of the medium on which data travel. [ABSTRACT FROM AUTHOR]

This paper aims to show the design and construction of a used oil rapid test kit. The kit allows evaluating used oil degradation and contamination by crepitation, oil blot, viscosity and particle content test. It consists of four units: oil blot maker, heating plate, falling ball viscometer and ferrous particle detector. The main contribution of the work are the devices and methods developed to accurately measure both the viscometer ball falling time and to detect wear ferromagnetic particles. The kit has produced satisfactory results compared to those obtained in laboratory tests. [ABSTRACT FROM AUTHOR]

This paper presents the redesign of an assembly line in the manufacturing of UAVs used in various missions that take place at high altitudes for the Research and Development Center of the Ecuadorian Air Force (CIDFAE). The methodology that was applied consists of three phases: the first one involves the analysis of the current strategic situation; the second one estimates the capacity of production, time standards based on the MTM-2 system; and the third one performs a distribution study of the plant facilities through simulation. As result a mixed distribution is chosen since it guarantees a production batch of UAVs. The parts are produced in manufacturing cells and the final assembly in workstations. Furthermore, strategies for strengthening the operational capacity of the plant will be established in order to manufacture three UAVs every two months. [ABSTRACT FROM AUTHOR]

This paper presents the design and development of a Virtual Learning Object. The aim is to achieve a computational teaching tool that facilitates the understanding of the course topics and allows the assistance of students during their independent study hours of the Basic Electronics course offered by the Computer Science program at the Universidad Cooperativa de Colombia. To develop this tool, the MEC (Computarized Educational Material) methodology proposed by Galvis Panqueva was used; this method includes the phases of analysis, design, development, testing and deployment. Pedagogical components were analyzed by identifying learning styles; for this, a survey of the Felder and Silverman type was conducted to a group of students. The Virtual Learning Object permits three types of user, for whom specific roles were defined and controlled by login features that enable or disable the options for each role, contributing to fulfill the tasks of the course. [ABSTRACT FROM AUTHOR]

This paper is focused on the identification and elimination of waste in building construction process in the city of Bogota so as to increase productivity. The methodology for gathering information was direct observation supported by digital images. Common causes of construction waste were identified, such as insufficient materials, inefficient material distribution, rework, and weather, among others. The data collection method also included construction workers interviews to identify motivational aspects and other general issues that affected productivity. Factors like salaries, workplace environment and mood were identified. Finally, discrete event simulation models were created for the real scenario and different scenarios were proposed. [ABSTRACT FROM AUTHOR]

This paper presents prospective methods implemented during the development of Surveillance Technology in Electrical Vehicles and Prospective Technologies in Colombia. These methods are developed for identifying related lines of research and emerging technologies which foster innovation. Methodologies are Delphi rounds and the planning of future scenarios. Both methodologies are implemented as tools to identify research topics that revolve around EVs in Colombia. The topics selected following the development of technology forecasting, were discussed by a group of experts who contextualized the information obtained from Colombia. From this analysis, scenarios were constructed. Technologies hampering the incursion of EVs in Colombia were determined, as well as the technologies with the greatest trend to be consumed and the most influential regulatory aspects. [ABSTRACT FROM AUTHOR]

This paper presents the application of Borda's multi-criteria decision-making method for stock portfolio in the Colombian stock exchange. The research question addresses the design of a methodology for investment decision- making in variable return markets by considering return and risk criteria. The approach used includes the integration of traditional and modern techniques with Borda's multi-criteria method; in this way, it allows assessing a number of choices under several criteria by assigning a determined score according to their relative position. The methodology set forth is adapted for the problem of selecting a portfolio in the Colombian stock exchange. The results obtained show the efficiency of the Borda method to find a suitable balance between return and risk. [ABSTRACT FROM AUTHOR]

One way to evaluate the internal problems of companies and to know the sources of their competitive advantages is studying its resources and capabilities. Resources are the basis of capabilities, which can be developed and converted into strategic capabilities that lead to obtain a competitive advantage or equality. This paper proposes a methodology to identify and assess the current capabilities of industrial SMEs in a region in Argentina in order to find its competitive effect. In this way, four main capabilities called management, innovation, marketing and integration are defined. At the same time, capabilities are divided into "sub-capabilities" comprised of resources. They are evaluated to determine if they are present in the companies studied. Subsequently, the VRIO test is used to define the competitive effect of the capabilities. The developed methodology systematizes the evaluation of strategic capabilities in the framework of the theory of resources. [ABSTRACT FROM AUTHOR]

Contrary to "productivity paradox" assertions, this reflection paper aims to show that ICTs have contributed to the growth of the productive sectors of companies and Nations, encouraging at the same time, the constant increase of processors' capabilities, as stated by "Moore's law". It will also address concepts such as ICT, Technological convergence, and Digital divide. It is based mainly on an official documentation study of both national and international authorized entities. As a conclusion, it was identified that "Moore's law" remains in force whereas the "productivity paradox" is just a myth, since, thanks to the use of ICT in their activities, companies and Nations have achieved not only to increase their productivity, but to keep it at a constant growth in all sectors that, at its utmost extent, affect domestic and global economies. [ABSTRACT FROM AUTHOR]

This paper describes the restructuring of an inverted pendulum prototype in order to recover its functional capacity and perform local control to uphold pendulum's arm upright position. Regarding control, state-feedback control feasibility for the experimental prototype using a low-cost process device was studied. For this, the design and implementation of signal conditioning circuitry for measurement, performance, and control devices was accomplished. An experimental procedure was performed to validate the mathematical model proposed for the system, and therefore, the state-feedback controller was designed based on this. State regulation towards zero was obtained on both simulations of the model and the experimental rig when trying to keep the vertical position of the pendulum. Ongoing tasks include the analysis of advanced state-space control techniques and considerations regarding nonlinearities in the model of the system. [ABSTRACT FROM AUTHOR]

Industrial processes are usually the major contaminants of the planet either by gas emissions produced during their processes or by the waste they generate. One of the most polluting industries is brick production since it uses a lot of coal and supplies such as tires to generate energy. In this paper, the design and construction of a cement and PET-flake (Polietiline terephthalate) brick is expounded. For this purpose, various compositions were studied through different resistance and compression tests using a PCEMTS500 tensile testing machine. The results show a resistant product comparable to the commercial one -according to the Colombian Technical Standard NTC 673, regarding compression resistance tests for normal concrete cylinders-; this standard sample presented an optimal compressive stress of 5600 kgf, whereas commercial bricks have a maximum stress of only 4480 kgf. Comparative costs were also analyzed to those of the current market, offering an excellent cost benefit option as well. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to present a methodological reference for the creation of Virtual Learning Objects, which is based on the analysis of the current pedagogical model of the University of Boyacá, Colombia, the definition of a learning object, the conceptualization of the methodology, its objectives and structure, and the different phases that it comprises. UBoa, hence, becomes a mediator supporting a quality control phase, which allows the organization of processes and validates the information to publish VLOs that meet the educational requirements and techniques of a virtual pedagogical model. This reference is the result of a collaborative and multidisciplinary work to support the construction of both b-learning and e-learning modules. [ABSTRACT FROM AUTHOR]

Transformation loss calculation is the main objective in this paper. A new method that considers load asymmetry and variability, as well as the presence of power quality (PQ) problems - like unbalance and voltage variations - is proposed. The method takes advantage of existing data from measurement systems installed in substations and it is based on probabilistic methods. It was applied to primary distribution transformers in the municipality of Cumanayagua. This method was compared with the so called "fast calculation method" employed nowadays; its advantage is demonstrated. The method can be generalized for industrial threephase power transformers to evaluate its energetic behavior. [ABSTRACT FROM AUTHOR]

This paper analyzes the possible impact of a massive replacement of incandescent lamps for power saving lamps -standing out CFLs (Compact Fluorescent Lamps) and LEDs (Light Emitting Diode) among them- on electric distribution networks. It is expected that, in a short or medium term, these emerging technologies will replace the incandescent lamps, inasmuch that since June 1, 2011, Argentina, following rules implemented in other countries, started banning the sale of incandescent lamps of 25 W or greater. A residential distribution network was modeled and simulated, and the influence on the power quality indices of the progressive increase of lamps with high harmonic components was investigated. Distortion levels could exceed the limits established by the regulations in force, but would not reach very excessive values. [ABSTRACT FROM AUTHOR]