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This paper evaluates economically build a new cogeneration plant with clean energy from forest biomass company Norske Skog Bio Bio (NSBB). This is to show that this plant-based forest biomass for electricity generation is a viable option in Chile from the economic and environmental perspective. For this evaluation, we propose an approach that uses “real options theory" based on the application of log-transformed binomial method with six steps. Also, comparing the results obtained with this approach, the results using traditional methods. It is found that for all cases studied, the value yielded by the real options method was higher than estimated by traditional methods. It is concluded that this alternative profitable investment. [ABSTRACT FROM AUTHOR]

The objective of this paper is to present, to those neophyte researchers, a set of hints that facilitate manuscript writing and publishing processes needed for high class scientific journals. In the scientific community, a research would only be completed when the results are shared through papers in peer-reviewed journals that guarantees the originality, importance and scientific validation of reported contributions. Consequently, researchers have the necessity to develop skills and abilities in scientific writing. However, the manuscript preparation process from the initial phase to the final publication is usually slow and difficult, due to some key factors having infiuence over its quality. In this paper, we present general guidelines about manuscript preparation and we give some hints about good scientific writing practices. The aim of these hints is easing the review done by the peer-reviewers in the evaluation process. In this sense, this work contributes to the newcomers in scientific research socialization. [ABSTRACT FROM AUTHOR]

The modeling and prediction of time series is an arduous and essential task for financial optimization procedures. Numerous studies have been carried out to reduce investor uncertainty, by forecasting the price of currencies and shares. However, the emergence of a new type of coins with their own characteristics, known as cryptocurrencies, present additional challenges. In this sense, the paper seeks to understand up to what extent comments in social networks can capture the collective expectations of investors, and affect the future value of the currency. The objective is to predict the daily performance of a market based on two components: those that define the behavior of the cryptocurrency itself (volume, opening value, closing value, maximum value and minimum value) and the expectations and interactions of the environment, through the collected tweets. For this, the use of a type of recurrent neural network known as "Long Short Term Memory" (LSTM) is proposed. The methodology used for the preprocessing of the data and the application of this time series forecasting technique allows obtaining a prediction with a Mean Absolute Percent of 34.92%; This indicates that the representation of the perception variable in social networks has not been that relevant and, therefore, motivates new works for better representation using other NLP techniques. [ABSTRACT FROM AUTHOR]

Project Management Office (PMO) design and use have been mainly based on praxis; nowadays, there is a demand for more scientific support. Additionally, the scientific work on the subject has been focused on business scenarios. This article develops a conceptual model of the main functions of the PMO in educational scenarios and a validated instrument at the content level that makes them measurable. The methodology consists of four stages (identify, describe, deepen, disseminate), which incorporate the general protocol of a systematic review, the critical incident method, inter-judge agreement, and content validation with experts. The initial sample obtained by the search algorithm, implemented in Scopus and Web of Science, consisted of 26 papers in educational contexts. Of these, fourteen passed the inclusion/exclusion criteria. These papers were analyzed, described, and characterized, which allowed the compilation of 167 critical incidents (specific functions of PMOs in educational settings), which were the input for the deployment of the consensus among judges. This article discovers and describes seven dimensions that synthesize the main functions of PMO in educational settings and 47 items that reflect their empirical manifestations and meet properties of clarity and relevance. The model and the instrument clarify what PMO functions are, what they represent and how they can be measured in educational settings. They are valuable for teaching, auditing, planning, intervention/control, and research on the topic. [ABSTRACT FROM AUTHOR]

This paper presents a review of the Demand-Side Management mechanism proposed for some utilities for residential load management. Also, this paper shows some Smart Appliances applications and Home Energy Management strategies developed and shown by some authors in the available literature that could be adequate strategies for improving Demand Respond inside the Smart Home context. Also, it is shown how Home Energy Management based on different Demand-Side Management strategies, could reduce peak load demand and save costs of power for end-users. Finally, the conclusions are presented. [ABSTRACT FROM AUTHOR]

In software development, smells are parts of source code that suggest a deeper problem in the system such as duplicated code. Specific knowledge and skills are required for identifying, correcting, and preventing bad code (smells) in the software development process. Such knowledge and skills can be learned, trained, and tuned. Some researchers have evidence about the usage of educational games for motivating, teaching, training, and improving several skills. By using principles of educational games, some authors propose strategies for software development teams to adopt good practices, but these proposals suffer to show different types of code smells and strategies to correct them. In this paper we propose Smellware as a game for teaching best practices in the software development process. The paper describes the game structure and the results of its app. ication in students of software engineering. This proposal aims to strengthen the skills of software developers for identifying and addressing several types of bad code smells and raise awareness about the effects of these bad practices in software development. [ABSTRACT FROM AUTHOR]

In lithium mining in the Argentine Northwest, mining companies are located strategically, depending on the availability of brines, but far from urban centers. Therefore, when selecting the right provider, it is necessary to consider multiple criteria. This paper presents the first multi-criteria decision model for the selecting suppliers in the lithium industry in the Argentine Northwest, in which a criterion of great importance for the region is considered and which is novel for the sector. From it, companies can select the best supplier through a ranking of qualifications without the variation that the preference of the person making the decision supposes. Fuzzy Analytical Hierarchy Process (FAHP) methods were integrated with Fuzzy Logic and the SCOR model. Therefore, it can be used in environments of uncertainty and ambiguity, combining quantitative and qualitative information. 6 criteria were defined with 3 levels of assessment: Quality, Price, Financial Solidity, Performance, After-sales Service, and Belonging. 729 combinations with possible selection results were obtained. This model was applied to four local suppliers by evaluating the input criteria. The result of the output variable Supplier Preferability was obtained, and from this, it was established which of them should be selected. This model it is expected to contribute to the decision-making of mining companies in the area. [ABSTRACT FROM AUTHOR]

The combination of marketing and production integrates functions that generate profits in the business environment and provide organizational value toward a competitive advantage in the sector. Identifying opportunities in the design of new products corresponds to a task consistent with studying the factors involved in the strategies of participation and competitiveness in the different markets. The challenge is to determine the incidence factors in the productive processes and marketing activities, for which the objective of this study was to identify and analyze the most outstanding scientific publications between 2000 and 2021 in the Scopus database to establish the attributes of the most significant scientific relevance called research perspectives. Methodologically, a scientific mapping and network study was carried out to determine the documents and essential characteristics such as number of publications, most relevant authors, H index, institution of belonging, and countries of origin. Likewise, the tree metaphor and the R-studio software were applied to identify basic articles, structure, current articles, and research perspectives. The results suggest the existence of three lines of research that relate to the success of marketing and production: theories of production and marketing, optimal control of systems, and relationship models. Finally, an agenda of papers concerning future lines of research is presented. [ABSTRACT FROM AUTHOR]

This paper presents a State Estimation Algorithm for Distribution Networks based on the Unscented Kalman Filter (UKF). Instead of nodal voltages, this method uses nodal active and reactive power as state variables in the dynamic model. Different demand forecast algorithms to assist the prediction step were tested and compared. In addition, the algorithm includes the software package OpenDSS as a calculation engine. We used the 13-node IEEE distribution network to test the methodology by simulating several scenarios of measurement generation. These simulations were based on the measured values of a local energy distribution company. The results exposed different performance levels depending on the nature of the scenario and the selected forecast method. [ABSTRACT FROM AUTHOR]

This paper proposes several techniques for simultaneous localization and mapping of the environment, which allow mobile robots to self-reference themselves in a navigation environment with reduced accessibility by external means, such as the Global Position System (GPS). The methodology consists of implementing four unsupervised machine learning algorithms, using data sets generated based on a cloud of range points delivered by LiDAR sensor measurements. The proposed approach identifies characteristics from a navigability map, whereas an additional method based on Extended Kalman Filter (EKF) allows to find the robot positioning in conjunction. The proposed approach identifies navigability map features and an additional method based on EKF. EKF allows finding the robot positioning that is conjugated with each of the proposed algorithms. The first proposed method consists of estimating the features of the environment using heuristic methods and shaping the map using geometric principles. The second method is based on K-Means to incorporate the uncertainty in the sensor measurement, while the third solution uses the Gaussian Mixture Model (GMM). The fourth method focuses on Density-Based Spatial Clustering (DBSCAN). An odometry error is induced in the robot to include uncertainty within the test environment, which propagates into the positioning readings. The results show that DBSCAN presents a better execution time for the proposed localization system than the other comparative methods. Additionally, the robot's localization is more accurate with this method, showing a 5% reduction of the error compared to the result obtained from the other proposed algorithms. Finally, with the results achieved, it is expected that the consumption of robot resources can be reduced with the reduction of localization error and automatic mapping. [ABSTRACT FROM AUTHOR]

Learning curves have been frequently applied in production/operations management and various logistics processes in many manufacturing and service organizations. However, studies on their integral use in the supply chain are recent. This paper contributes to filling this knowledge gap by measuring the impact of learning on lead time in logistics management systems. The empirical study was used as a methodological tool to demonstrate this. The logarithmic-linear models, with their terminology and calculation equations, were applied to three case studies representatives of the logistics systems proposed by the Supply Chain Operations Reference (SCOR) model: make-to-order, make-to-stock, and engineer-to-order. As a result, the first two were adjusted to the Stanford model and the third to De Jong's model. Their learning curve, mathematical equations, and a sensitivity analysis were determined. This approach demonstrated its relevance and difference compared to previous publications, which mainly analyze links or parts of the CS. [ABSTRACT FROM AUTHOR]

This work shows a technical-economic procedure to determine the adapted network in a low voltage (LV) residential electrical system with photovoltaic distributed generation (PVDG). A network is adapted when it is designed to minimize the total fixed and variable costs and optimize the equipment to adequately satisfy the demand (both the current demand and its expected growth). The study will consider that the decision to install PVDG is exogenous. The method is based on the concept of Hosting Capacity (HC). This paper analyzes four typical LV networks in the city of Buenos Aires, Argentina. A statistical power flow solves the networks. We take the following statistical variables: residential load, PV penetration, PV power, and location. We obtain the statistical HC for each network, and the HC is used to carry out the technical-economic study of the network. Finally, we establish the adapted network for each level of penetration. The results show that, without PVDG penetration, there are different network options with different costs per km2. When PVDG penetration increases, the networks with the lowest cost per km2 are discarded (due to their FCE), and only the networks with the highest cost per km2 survive. Once 70% penetration of PVDG has been exceeded, none of the studied networks is considered an option.. [ABSTRACT FROM AUTHOR]

The society of the 21st century requires training of engineers capable of solving problems in applications of the limit of real functions. In this paper, the mathematical skills of three engineering degrees belonging to the 2019 cohort of a public university is analyzed. The objectives of this study are to investigate the skills of undergraduate students in solving of mathematical problems, defined according to their nature in routine and non-routine, and according to their context, in real, realistic, fantasist and purely mathematical. Also, identify and characterize the types of problems addressed, and to solicit the opinion about the level of difficulty of the problems involving the limit of real functions and on the prior knowledge that they need to achieve a better performance in their resolution. Students from three different engineering programs volunteered to participate in the study. The evaluation tool used consisted of a function limit application problem solving test, which was content validated by eight experts in the field, and an open-ended opinion questionnaire. The results favor the performance of the students in solving routine problems in fantasist contexts, and even are guarantee development the mathematical skills necessary to solve non-routine problems of application of limits. [ABSTRACT FROM AUTHOR]

This paper presents a study of magnetic flux density in a large synchronous large size machine when it is working as a generator. Finite elements software has been used to obtain the same physical and electrical characteristics of the real machine. From the results conveyed from the simulations, it is possible to find the optimal points where the magnetic flux sensors will be placed and to determine short-circuit faults in the rotor coils. The work results are also a reference to evaluate and compare the magnitudes taken by the sensors without creating short-circuits in the actual machine coil. Besides that, the proposed model based on finite elements can be used to make simulation tests of new kinds of sensors. [ABSTRACT FROM AUTHOR]

Knowledge transfer in software development teams allows their members' non-externalized knowledge to be collected, to form the organizational knowledge from a repository and share it among them. During this process, difficulties may arise in making this knowledge available, which may be associated with the lack of collaboration and motivation of the team, as well as poor communication and little support from the organization. Given these difficulties, the GamifiK strategy, supported by gamification, was proposed to foster collaboration in the transfer of knowledge in software development teams. This paper used an empirical research approach with a quasi-experimental design in an academic context to evaluate the collaboration of agile team members in sharing their knowledge and contributing to knowledge transfer. A statistically significant increase in team productivity was perceived, reflected in the ability to perform more user stories per sprint and complete incidents in less time. GamifiK is a promising strategy for fostering collaborative knowledge transfer across software development teams. [ABSTRACT FROM AUTHOR]

This paper presents the modelling and simulation of a complex system applying the hierarchical coloured Petri nets method to represent the failure and repair processes, as well as obtaining statistical data indicating its performance. The simulation was performed on the model of a mechanical system characterized by the FAMAE SG 542-1 war rifle, commonly used in the Chilean Army, through the CPN Tools and Python software representing how components perform of operation of this weapon. This behaviour is recorded through both software, obtaining the simulation data so that it will be possible to predict the condition of a component and the system in the future to generate corresponding action plans. [ABSTRACT FROM AUTHOR]

In this paper, the structural seismic performance is evaluated by nonlinear analysis according to the ASCE/SEI 41-17 methodology, and the probability of collapse of structures subjected to 11 ground movements, scaled to hazard levels corresponding to serviceability, design, and maximum considered earthquakes, is determined. Three-dimensional Finite Element Models (FEM) of one, two, and threestory frame structures are evaluated subject to eleven different ground motions, selected and scaled to represent these hazard levels. Following the methodology mentioned earlier, collapse probabilities are estimated for RC frames typical of Ecuador. Structures in this study are divided into two categories: Those designed according to seismic-resistant engineering practice and those built without engineering design. For each category, infilled and non-infilled frames are distinguished. Infill masonry negatively impacts structural performance and the collapse probability of frame structures. Damages observed during previous earthquakes are consistent with the results of this study. [ABSTRACT FROM AUTHOR]

The present article proposes a system of a quantitative assessment of the ability of inspectors to make correct decisions, applying an R&R study by attributes, with the method of risk analysis, supported by contingency tables and the Cohen Kappa index. Additionally, it establishes a tool to simplify the required calculations and a proposed inspection method that seeks to reduce the variability associated with the inspection process. In this paper, a simulation study is made. We simulate several quality inspectors and three sceneries. Results show a quality level between 95% and 99% was obtained. It is possible to show that reducing the variability of inspection processes results through standardized methods, criteria equalization, and staff training improves the quality level process. The procedure presented and simulated in this article can be applied in the qualitative inspection, such as manufacturing processes as services processes. [ABSTRACT FROM AUTHOR]

Due to the constant growth of global environmental pollution, the sectors related to the electrical industry have focused on finding solutions to achieve efficient energy consumption. Among the devices that have been incorporated to carry out improvements in electricity consumption are smart sockets. This paper presents a prototype for a general-purpose smart socket. The design considers the main components of a smart plug: measurement unit, control unit, processing unit, and communication interface. The prototype is based on free hardware, with easy access, low cost, and consumption. This work successfully developed a device capable of measuring, controlling, and monitoring the electrical behavior of equipment connected to the power grid. Additionally, it incorporates temperature, light, and humidity sensors to complement the electrical measurements. The prototype presented offers the possibility of developing many functionalities and services aimed at energy efficiency on the topic of the Internet of Things (IoT). [ABSTRACT FROM AUTHOR]

Games for educational purposes have been used in different areas as supplementary strategies to the traditional teaching-learning process. Software Engineering-applying methods and techniques for building high-quality software products-also includes games in the professional training process. In order to provide a tool for teacher guidance about their use in their teaching-learning process, several game classifications have been proposed. However, existing classifications consider the game purpose and the target audience, but they omit variables associated with the structure of the game-e.g., rules or materials. This paper proposes a classification of games for teaching software engineering considering purpose, scope, and fun components. This proposal defines the key features of any game for teaching software engineering and provides alternatives to professors for incorporating this teaching tool in their training process. The proposed classification was applied to a set of 17 games oriented to software engineering teaching, showing its potential as a support tool in the analysis, comparison, and selection of games for teaching this discipline. [ABSTRACT FROM AUTHOR]

There are multiple technologies for transporting info-communications between objects and machines for the internet. Two of the most robust and with the highest coverage and support for multiple users are 4G and WiMax IEEE 802.16x. This paper presents a simulation of land coverage of both wireless communication technologies as a broadband communication alternative for new free, private, or supported operators by public institutions, such as municipalities or regional cooperatives. The cases of the cities of Riga, Bucharest, Florianópolis, Santiago, Concepción, and Copiapó were studied. The study uses Radio Mobile GLOBE-BIL software, obtaining propagation coverage graphs on digital SRTM terrain elevation maps released by NASA. This simulation determines the number of antennas required for millions of users in the context of the Internet of Things. It quantifies the square kilometers of wireless propagation coverage that can be technically achieved for each project city. The results show that WiMax supports a more significant number of connected users, has better coverage, and requires fewer antennas. On the other hand, for the propagation coverage indicator, the results for 5 cities are better for WiMax technology than 4G, except for Santiago (Chile), where the best performance is achieved for 4G over WiMax. [ABSTRACT FROM AUTHOR]

This paper presents multitasking programing of a three-phase speed variator development. This focus has not been reported in technical literature, although it is relevant for engineering power electronics developers, students, and researchers. Hybrid multitasking programing is proposed for the implementation of task that speed variator must carry out. Needed tasks in the speed variator are described and programed in a microcontroller (dsPIC30F4012) using state machines, considering times and priorities with preemptive and cooperative multitasking. This paper proposes a programing form for speed variator that allow software develop since its early stage. The programing structure enables the use of microcontrollers with lower performance. Thus reduction of production costs could be achieved. A three-phase speed variator is presented that can change output-voltage frequency and amplitude without stops or interrupts. Validation of multitasking programming is done on an experimental prototype developed in the laboratory, evaluating the execution times of tasks. [ABSTRACT FROM AUTHOR]

This paper analyzes three path planning techniques to solve a ball-maze system with a two-degree-offreedom platform. The system's objective focuses on the ball traveling a path from an initial point to a final point (defined by the user) in the maze. The RRT algorithms (Rapidly Exploring Random Trees), PRM (Probabilistic Roadmap), and Voronoi diagrams were implemented using the A* search algorithm. The system architecture consists of four subsystems called mechanical, vision, planning, and control. The main contribution of this work is the evaluation of the algorithms on a physical system and a complete results analysis (graphical and analytical). The experimental tests were performed based on analyzing four different maze configurations, the run time, and path length metrics. In this context, 20 algorithm executions were developed for each configuration, then the meantime and mean length and their 95% confidence intervals were determined. The main results show that the RRT algorithm presents a more significant variation in its data, the longest path length, and the best performance in terms of run time. Moreover, the PRM algorithm generates the path with the shortest length but has the worst performance concerning run time. Finally, the Voronoi diagrams' technique takes less time to execute, has less variation in its data, and presents the smoothest and equidistant path between the maze walls. [ABSTRACT FROM AUTHOR]

Balancing methods for mechanisms have been used over the years to extend the lifespan of machinery by reducing vibration, wear, and fatigue on their components. These techniques have grown in effectiveness but also in mathematical complexity. Nowadays most balancing methods use Cartesian coordinates, which generate complex equations involving trigonometric functions that are difficult to simplify. This paper presents the use of natural coordinates to obtain the balancing parameters of a simplified crankconnecting rod-slide mechanism avoiding the use of trigonometric functions. The balancing optimization of the mechanism is carried out by using a stochastic optimization algorithm based on populations allowing to reduce the Shaking Moment (ShM) by 97.76% and the Shaking Force (ShF) by 94.58%. [ABSTRACT FROM AUTHOR]

The Lean construction philosophy has been welcomed by numerous companies in Colombia for a little more than a decade. The Last Planner System (LPS) is among the implemented tools found, a planning and control system that seeks to accomplish a continuous workflow. The system implementation results vary from one company to another, and there is no investigation to date that shows the diagnosis of the adoption of this tool in the country. This paper aims to illustrate the degree of implementation and functioning of the LPS from different perspectives found in sixteen Colombian construction companies. Data collection was carried out through non-participant observation during the weekly planning meetings, surveys conducted to construction professionals, supervisors, subcontractors and labor, and a semi-structured direct interview with the managers of the Lean area in the companies. Analysis of compiled information shows multiple ways of applying this tool, conceptual and practical failures, and a lack of training and permanent feedback that does not allow to be a part of the corporate culture were all identified. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the relationship between leadership and performance in teams of higher education students. For this, first, we conceptualize leadership as an influence process between team members and, second, we model this team process using social network analysis. To study the proposed relationship between leadership and performance, we conducted a study at 164 students of 41 teams of industrial engineering students of two universities in Chile. We analyzed our data using linear regression analysis, and our results showed that leadership network density is positively related to performance, and leadership network centrality is negatively related to performance. These results help teachers, and higher education institutions have a reliable statistical tool to track student leadership development throughout the curriculum. [ABSTRACT FROM AUTHOR]

The benefits of implementing Demand Response (DR) programs in large consumers have been widely documented. However, it is still necessary to explore in more detail the impacts of the implementation of these programs in residential users on the benefits of the distribution system operators. In this paper, we determine the effects of Demand Response (DR) on the reconfiguration of a distribution system considering the consumption characteristics of residential users in Colombia. For this purpose, the demand curve of a typical residential user was constructed for Bogotá D.C., and measurements were taken to estimate the participation of this user in a DR program. In addition, an algorithm based on Particle Swarm Optimization is used as a solution strategy for the reconfiguration problem. The results show that a distribution system reconfiguration could significantly increase the revenues obtained by a Network Operator. However, it is shown that the reduction of energy losses obtained from the DR would not provide sufficient incentives for them to promote the participation of residential users in this kind of programs. [ABSTRACT FROM AUTHOR]

Proportional-integral-derivative (PID) controllers are widely used in industrial control systems and control theory academia, mainly due to their functional simplicity and robust performance. This paper presents the performance comparison of a PID controller, implemented with two different technologies, (i) a SIEMENS SIMATIC S7-1200 programmable logic controller and (ii) an embedded system based on RASPBERRY PI. The parameters were set with the same conditions for both technologies. The control was performed on a level system on the platform located in the process control room and computerized systems at the Electricity and Industrial Automation Center (CEAI), SENA in Valle del Cauca, Colombia. The results obtained indicate that, for both technologies under the same conditions, the controllers have the same performance in terms of settling time, rise time, delay time, peak time (time where the maximum overshoot occurs), and steadystate error. Makeover, they differ in the control effort where the PLC performs 2.10% less control effort than the embedded system and a signal overshoot of 2.05% compared to 4.32% of the embedded system. These results show that controller implementation with an embedded system is an excellent low-cost alternative for industrial processes with similar results as a controller implemented in a PLC. [ABSTRACT FROM AUTHOR]

In this paper, a computer vision inspection methodology is presented for the detection and segmentation of areas of wear by electric arc on the surface of electrical contacts using segmentation by instances. Cadmium is a toxic metal frequently used in the manufacture of alloys for electrical contact, so efforts have been made to replace or eliminate this element from the industry. Our work proposes an approach oriented to the automation of the inspection process, which reduces the subjectivity of the repetitive task of inspecting electrical contacts, allowing to compare two different alloys, such as one with Cadmium (Cd) and the other with Copper (Cu)., subjected to the same conditions and determine which of them presents less wear by electric arc. In this way you can know if the new part is better, equal or worse in terms of performance. Initially, an adaptation was made of the source code hosted in a github repository of mask R-CNN of the Matterport corporation, where variables, classes were modified, and directories were created according to our needs. The results obtained show that the masks generated by the algorithm adjust very well to contact wear, despite the irregular shape of the damage. However, the "charred" edge was probably not considered, because in training images it was a feature that few images presented, so segmentation may not be considering this factor. [ABSTRACT FROM AUTHOR]

The purpose of this paper has been to investigate the relationship between intellectual capital (IC) and financial performance, based on two constructs, human capital (HC) and relational capital (RC), measured in financial terms. The methodology was applied to a sample of Universities of Chile. This was done at public and private universities during the 2014-2018 periods. In this investigation, we used descriptive statistics, level of correlation, and panel data analysis to demonstrate the existence of a positive relationship between each component of IC and the performance of universities, measured in terms of financial performance. The panel results confirm the hypothesis that HC and RC positively impact the university financial performance (return on equity, ROE, and return on assets, ROA). The article contributes to improving the conceptualization of Intellectual Capital and its relationship with the financial performance of Universities. [ABSTRACT FROM AUTHOR]

In this paper, a conceptual model for technical microgrids conception applied to a case study in Colombia is presented. The model considers aspects as: medium voltage electrical system topology setting, preselection of generation technologies, electrical demand prioritization, generators location employing the voltage Stability Index (SI), operation strategies and capacity sizing of distributed generators, components modeling and the evaluation of microgrid performance in aspects as voltage profiles and optimal power management. The conceptual model developed was applied in a case study for the Valle del Cauca region, Colombia, which presents urban and agroindustry areas suitable for the research requirements. For the microgrid steady-state performance evaluation, the computational tool of power systems analysis Neplan® was used. [ABSTRACT FROM AUTHOR]

This paper presents comparison of Standardization and Scaling methods in cost predicting. Four methods were used for pre-processing dataset; after that, data was processed through artificial neural network (RNA). The first step was to build common variables in information projects based on opinions of some project managers. Second step was to simulate dataset based on information provided by CRConsulting. Third one was process data with machine learning according to the four methods proposed, RNA algorithms were the same in four cases. Last, the comparison results were presented through adjustment models according to the applied method. [ABSTRACT FROM AUTHOR]

This paper presents a particular case of the facility location problem. The characteristic of this problem is that it contains a set of clusters or nodes that represent the accumulation of clients who demand a single product. It is desired to locate P distribution centers (DC) where the demand of clusters is only satisfied if we located a distribution center in this cluster. Moreover, the number of capacitated plants and its location must be determined in order to supply the different distributions centers. The objective is to maximize the utility by considering, in one hand, the incomes that are obtained for satisfying the demand of different clusters and in the other hand, the installation costs incurred when locating the Distribution Centers and the plants as well as the costs of material transport from the plants to the distribution center. Other applications of this problem are appreciated in telecommunications networks, electrical networks, etc. The paper also present a new model of integer programming that allows to solve small instances, up to 300 clusters, in an acceptable CPU time, the problems were programmed with AMPL and solved with CPLEX 11.0. For two larger instances the authors present heuristics, which allow obtaining solutions with a GAP least than 1%. [ABSTRACT FROM AUTHOR]

This paper describes the generation of signals for radio over fibre system based on electrical combination of baseband and radiofrequency components. In these systems, the radio frequency carriers are conveyed as optical subcarriers over an optic fiber link in a point-to-point or point-tomultipoint connectivity paradigm. Radio over fiber systems are considered as the cornerstone over which next generation networks will be founded by allowing a single physical platform to supports the information exchange from both fixed and mobile users. The paper analytically describes the signal generation process by defining the electrical field as a function of the baseband and radiofrequency signals modulation depth. By means of modeling an electrical field, it was found a trade-off between the modulation depths of both signals; as well as the their optimum value in order to assure a good signal a the transmitter output. [ABSTRACT FROM AUTHOR]

This paper presents the evaluation of oxidation of organic matter in water via the determination of kinetic rate indicating the frequency at which the stream loses or gains oxygen and nitrification rates and the decay of pathogens. The fee calculation defines the process of auto purification and assimilative capacity of the organic load on the Frio River, the main source of potable and irrigation of the municipalities of Floridablanca and Girón in the Department of Santander, Colombia. 26.6 km of river were modeled, ie, the entire main channel basin, which characteristic is to be a highly oxygenated mountain river in its upper part, but in the low polluted area, which capture 26.2 Ton.d-1 of biodegradable material from household waste. The calculation of these rates is developed through correlations and numerical analysis of concentrations in each of the (7) reach of the river. The model of behavior of: Oxigen, carbon, nitrogen, pathogens and suspended solids through QUAL2K, in order to corroborate the behavior of the calculated rates: studies of dispersion coefficient, morphometric and hydraulic analyzes were developed. Knowing the auto purification of water sources is critical to establishing sustainability strategies.This paper presents the evaluation of oxidation of organic matter in water via the determination of kinetic rate indicating the frequency at which the stream loses or gains oxygen and nitrification rates and the decay of pathogens. The fee calculation defines the process of auto purification and assimilative capacity of the organic load on the Frio River, the main source of potable and irrigation of the municipalities of Floridablanca and Girón in the Department of Santander, Colombia. 26.6 km of river were modeled, ie, the entire main channel basin, which characteristic is to be a highly oxygenated mountain river in its upper part, but in the low polluted area, which capture 26.2 Ton.d-1 of biodegradable material from household waste. The calculation of these rates is developed through correlations and numerical analysis of concentrations in each of the (7) reach of the river. The model of behavior of: Oxigen, carbon, nitrogen, pathogens and suspended solids through QUAL2K, in order to corroborate the behavior of the calculated rates: studies of dispersion coefficient, morphometric and hydraulic analyzes were developed. Knowing the auto purification of water sources is critical to establishing sustainability strategies. [ABSTRACT FROM AUTHOR]

Circuit breakers serve to connect and disconnect electric circuits under any operation conditions. Improving circuit breaker reliability is important for the correct operation of electric power systems. In this paper, we use one of the existing methods for the analysis of reliability in devices and components according to Norsok Standard Z-013. The criticality level of the circuit breakers in a substation is determined from the quantity of operational failures, the power flow through the circuit breaker, and the circuit breaker incidence in the electric power system stability. The paper includes the analysis of historical data over a five-year period and shows the results of the obtained mathematical expression. These results will allow developing maintenance strategies directed towards the most critical circuit breakers to improve their reliability. [ABSTRACT FROM AUTHOR]

In this paper is addressed how in the literature of Mechanic of Materials and Machine Elements Design only few authors address the subject of welded joints, among those can be mentioned Shigley Hall, Reshetov, and Faires [1, 3, 4-5]; although they provide expressions to calculate stress in complex geometric configurations of welded joints, they do not analyze calculation for butt welded joints subject to torsion, neither take into account characteristics of thin-walled side faces for the calculations. Only in the General Treaty of Schimpke Welding, Horn and Ruge [7] are mentioned these features without addressing the expressions for the calculation of stresses in cases of complex cases. Similar case is seen in articles and specialized literature wheredelves into research on the technological parameters in welding, materials and other subjects without addressing the improvement of calculation expressions to determine the stresses in such joints. In this paper new expressions are shown for the calculation of tangential stresses arising on the welds on butt joints of open profiles under free torsion, taking into account thin-wall side faces. [ABSTRACT FROM AUTHOR]

University dropout is a problem related to the student, as a direct responsible, and with the university institution, knowing the possibilities of attrition is relevant for the institution. In this paper, it is proposed to use classification models to find patterns and predict possible dropouts in university students. An application has been implemented that uses information provided by the university and that generates classification models from different algorithms (neural networks, ID3, C4.5), and uses the most significant attributes within the available information. The performance of these models was compared to define the one that provided the best results and that will be used to classify the students. The results show that the algorithm of C4.5 presented improvements in performance with respect to the neural network and the ID3 and that the relation of credits approved by a student related to the credits that he should have taken is the most significant variable in the construction of the model, followed by the qualifications, while the modality of the admission exam through which the student entered the university did not turn out to be significant, since it does not appear in the generated decision tree. [ABSTRACT FROM AUTHOR]

This paper presents the review of three main existing agile approaches: Scrum, Lean Software Development and Kanban, which served as the basis for the development of a proposal for a new approach in Agile development. To achieve this, a description of each agile approach to software development and a comparison of their strengths and weaknesses are made. Then, the new proposal is established based on the integration of the three approaches, defining a set of metrics and developing a case study to evaluate the integration and obtain quantitative and qualitative data. The results obtained from the case study proved to be quite positive because it allowed us to comprehensively evaluate the new approach. These results represent a promising start to continue working in this line of research. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study, which compares the effect of the sensitivity against the cementation in the recovering of the stress-strain properties in clayey soils from "Sabana de Bogotá". The work methodology included three phases: (i) extraction of samples; (ii) properties assessment of the undisturbed samples; and (ii) stabilization and analysis of the resistance of the stabilized samples with cemented materials. An experimental plan, which included physical and mechanical tests, was developed. The plan had an emphasis on the assessment of the undrained shear strength and the elastic modulus through unconfined compression tests. The samples were compacted and stabilized with the addition of two solid chemical products, calcium carbonate and iron oxide. Results between natural, remoulded and stabilized were compared by means of statistical methods. Therefore, it was found that the use of iron oxide in this kind of soil allows obtaining stress-strain parameters close to the undisturbed state after the compaction process. [ABSTRACT FROM AUTHOR]

Maintenance approaches have been evolving from reactive to a preferred proactive conception with operational reliability as a new implemented strategy. This scenario suggests that a review of conceptual basis is needed. The paper resumes the study carried out with the main objective of building a new concept of operational reliability. Bibliographic research and poll methods were used. Selected specialists with remarkable profiles in Microsoft Academic Search, Google Schoolar and Research Gate were consulted in order to validate the formulated concept. A poll instrument based on Likert Method was designed whereas for analyzing the confidence, Cronbach Alpha Method was used. As a result, a novel concept of operational reliability was built and validated. This concept sets up a synergic based relationship among equipment, human resources and technological processes and, for the first time, provides support to obtain an indicator as a numerical representation of operational reliability. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the influence of the cutting speed, feed per tooth and machining strategy; on geometric quality of the machined surface, in the ball milling tool of the surgical grade titanium Ti6Al4V (In this paper, geometrical quality, is considered; parameters of surface roughness, dimensional accuracy and shape tolerance). The samples were machined by means of ball milling tool. Analysis of the influence of the factors was performed by means of a 2³ factorial experimental design. Further, an ANOVA (analysis of variance) was performed between concave and convex spherical geometries of the same radius, to determine the influence on the machined surface geometric quality geometric quality of the machined surface. Additionally, an ANOVA was performed; between convex spherical geometries different radius to determine the influence on the geometric quality of the machined surface. The factorial experimental design results showed that machining strategy factor on surface roughness parameters Ra. Furthermore, On the other hand, the ANOVA for the concave and convex spherical surfaces shows that the change from concave to convex surface influences geometric tolerance. Finally, ANOVA for convex spherical geometries shows that the radius changes influences surface roughness Ra, Rq and Rz, geometric tolerance and the dimensional accuracy. [ABSTRACT FROM AUTHOR]

The purpose of the performance evaluation is to measure the degree in which an employee of an organization adjusts or complies with the desired profile. The results of this measurement allow generating recommendations to improve the performance of the functions by the employee. Moreover, the results favor the human talent management, related to professional growth, bonuses, compensations, and candidate selection. In this paper, an analysis, comparing, and characterization process of the performance evaluation methods are presented. This process was realized to take advantage of the benefices of performance evaluation and identify which methods of performance evaluation are most used in software development teams. This analysis allows us to characterize these methods and identify the factors that determine their usage, as well as the criteria that allow them to specify and differentiate their application in the software industry. A methodology is integrated into three phases to carry out the purpose of this work. Through this methodology, it was possible to conduct the characterization of performance evaluation methods for software development teams. We identified 11 conventional performance evaluation methods and 10 approaches to performance evaluation for software development teams. We included conventional methods because the particular proposals for software development teams use some of them. From this set of studies, the analysis of characterization and comparison factors was established. This characterization shows that the evaluation of technical competences takes precedence, over generic, psychological, or experience competences. [ABSTRACT FROM AUTHOR]

The growing worldwide energy demand requires the design and construction of increasingly efficient generation systems. In satisfying this need, control schemes play an essential role. Having a system that allows experimental evaluation of their performance is key. In the case of wind energy, one possible control strategy is pitch regulation, which is used in variable pitch wind turbine systems. This paper presents the results of the design and construction of a testing bench for carrying out the experimental evaluation of control strategies for pitch regulated small wind turbines. Rotor operation and pitch regulation were ascertained through wind tunnel testing. Rotors start moving with winds of 3.5 m/s. PI and fuzzy controllers were implemented and tested. [ABSTRACT FROM AUTHOR]

This paper presents the design, simulation and implementation of a small scale battery charger with low harmonic distortion in current. It was proposed a design composed of two boost converters in cascade, the first operating as PFC and second as a regulator of the injected current to the batteries. Additionally, it was presented the procedure for the controllers design of each stage. In the first stage was used a control in average current mode and in the second stage were used two controls that enable you to employ the method of constant current - constant voltage in order to charge the batteries. In both stages were used the PI controllers and with the power electronic circuit were simulated in the PSIM® and MATLAB® software and validated experimentally In this tests, power factors close to 0.98 and harmonic distortion in current below 10% were obtained, complying with the requirements of the IEC 61000-3-2 standard. Finally, the conclusions are presented. [ABSTRACT FROM AUTHOR]

Currently, the software development industry presents challenges for processing business information, specifically that contained in textual documents. In the process of software requirements elicitation, a potential source of relevant information is business documents, since they can facilitate the knowledge understanding about a domain, as well as know the evolution of a product. Despite its usefulness, requirements engineers do not always use it for their work because of time and costs involved. In this paper this problem is addressed and it is recognized through a systematic literature review, the potentiality of using Natural Language Processing (NLP) techniques to extract relevant textual information from business documents, and the utility of its representation in conceptual models. Starting from this, a semiautomatic method of extracting information from business documents written in natural language in Spanish and its representation in a conceptual model is proposed. The method is supported in a reference methodological framework for Text Analytics projects, is based on NLP techniques, and the output is represented in a class diagram. The method was evaluated through a case study with software analysts in Medellin-Colombia, taking as input telecommunications resolution documents. The evaluation allows us to conclude that the model is a satisfactory approach to solving the problem, and some lines of work are identified to generalize a solution. [ABSTRACT FROM AUTHOR]

Falls are the second cause of death in the world. This is the reason why systems of falls detection, framed in the telemedicine field, are widely investigated nowadays. However, these systems often result in false positives. In this paper we propose the development of a fall detection system for people. The system is based on the use of a Kinect 2.0 sensor that allows monitoring from one to six patients and an alarm system that sends both a message and an image to the e-mail of the person who is taking care of the patient. The biomechanical analysis of the fall, carried out using iPi Mocap Studio program, and the fall detection algorithm, developed in LabVIEW graphic programming software, allowed measuring the position and velocity values of a selected point in the skeletonization of the person. Different actions were simulated, including walking, sitting, bending and falling. From the position of the point-selected point (spinebase) of the skeleton of the person, the velocity was calculated with the derivative. This characteristic allowed defining the linguistic variables and fuzzy sets to classify the type of movement. The system was validated with 3 people, of different ages and heights, in a controlled environment, achieving an effectiveness of 95.8% and the activation of the alarm system, creating a technological assistant of adequate and reliable aid that guarantees the integrity of the patient. [ABSTRACT FROM AUTHOR]

This paper presents a structural equations model (SEM) that measure the Urban Quality of Life (UQoL), taking as reference Cienfuegos's city (Cuba). The objective is to determine the variables that influence the UQoL, to develop a procedure that allows the design of two models: one from the objective dimension and the other from the subjective dimension of this concept. As main results a model of relations of management indicators, given by local decision makers and another model that relates perception indicators, given by citizens is showed. The comparison between these models makes it possible to generalize that variables such as health, housing and income are determining factors in the UQoL of Cienfuegos's city. [ABSTRACT FROM AUTHOR]

This paper aims to build a set of scenarios for its use in the solution of a stochastic two-stage optimization model for the redesign of the plastics recycling supply chain in Cuba and thus minimize the effect of uncertainty in this strategic decision-making process. The statistical information collected in the characterization of the supply chain is scarce and it is not enough to conform scenarios through the quantitative methods found in the literature. To solve this problem a diffuse inference system is used, which allows the linking of statistical information about the system and the knowledge of experts in recycling and supply chain management in a robust way. This methodology, applied to the plastics recycling in Cuba, makes it possible to increase the number of solutions of the model which, integrated to the twostage solution method, evaluates the solutions to find the most promising ones. A total of nine scenarios are obtained and the optimization of the proposed model is carried out with which a set of 225 solutions is obtained, finding as the best, for all scenarios, the opening of three recycling plants. [ABSTRACT FROM AUTHOR]

The shape memory alloys are metals that belong to a class of shape-memory materials. These kinds of materials can memorize their previous form when they are subject to stimuli such as electric, magnetic, and thermic variations. The metal alloys that exhibit this characteristic are commonly named "muscle wires" because their main objective is to generate motion without electric motors or coils. Published studies have demonstrated that, in the case of the muscle wires, their durability and reliability can decrease due a material overheating as a consequence of overcurrent. The design of a buck converter based electric energy supply system for muscle wires is presented in this paper. A control stage based on fuzzy logic is included in the system to regulate the current through the muscle wire. The electrical current adaptation to a maximum magnitude, specified by the muscle wire manufacturer, is achieved in the presence of disturbances, according to the simulation results of the proposed system. [ABSTRACT FROM AUTHOR]