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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 high levels of waste cellulose mud in paper production represent a severe environmental problem regarding its final disposal as a waste by-product. The accumulation of paper sludge and its possible recycling should be focused on its reuse in primary materials or those of continuous use that mitigate its environmental impact. This research was developed to characterize a clay material used in civilian construction with Eco-Efficient properties (hollow ceramic bricks), incorporating waste from paper factories (paper sludge or cellulose sludge) without affecting its mechanical response in comparison with traditional materials, but with the use and advantages of the utilization of residual materials. For this purpose, a physical-chemical characterization of the paper sludge was carried out, accompanied by a physical-mechanical characterization for the Non-structural block obtained with the inclusion of the sludge, in accord with dosages of 0%, 11.1%, 12.5%, 14.3% 16.7% and 20%. As a result, the organic and inorganic byproducts present in the paper waste byproducts were obtained, and the hollow ceramic bricks showed an increase in their mechanical compression capacity under considerable variations in coloration and size. [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]

In humankind's history, many natural and man-made disasters have happened and will continue to happen. In a post-disaster scenario, many processes and actors must be organized to provide the needed supplies to the affected people. Although it is similar to a supply chain, it is called Humanitarian Logistics in a disaster context. Many papers present centralized approaches to organizing different aspects of humanitarian logistics. However, a centralized approach is not always appropriate due to the dynamics and uncertainty present in a post-disaster scenario. This paper describes a distributed approach based on Multiagent Systems (MAS) to organize the elements of humanitarian logistics in a post-disaster scenario (MAS-HL). Intelligent agents in the MAS-HL, represent real-world elements, such as affected zones, distribution centers, donors, and trucks. The agents negotiate among themselves using a Contract-Net Protocol (CNP) to organize the operations of the elements represented. Due to dynamics and uncertainty in a post-disaster scenario, the agents must reorganize the operations of the elements. The MAS-HL is evaluated by simulating and evaluating a case study focused on bottled water delivery in post-disaster scenarios, they represent when major changes occur. The computational results confirmed that the MAS-HL quickly generates plans to organize the elements of humanitarian logistics and reorganize the plans when the environment changes. [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]

The rapid growth of the renewable energy market has provoked pressing challenges because of the significant financial resources required, highlighting the need for marketing of the electricity sector. The role of brand identity influences on customer image that affects demand changes and financial resources used by SMEs in the electricity sector. This paper presents a dynamic model-based analysis to understand better the role of brand identity in creating value in SMEs. The simulation model aims to assess alternative strategies of brand identity to support SMEs in the electricity sector to promote efficiently value creation. Simulation results show that the high customer value perception allows aligning the electricity utility industry to create more value. This dynamic perspective presents a new point of view that contributes to managers and policymakers in analysing the relationships of stakeholders. Thus, the paper will give some insights on the design of an alternative business model based on non-conventional renewable energy. [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 provides a numerical assessment of the ductile fracture of the AA6101 and AISI 4340 alloys using the Lemaitre and Gurson models. The simulations were carried out to verify the evolution of the accumulated plastic strain at fracture, assuming the high range of the triaxiality ratio, applying monotonic tensile loads on smooth and notched cylindrical specimens. The numerical strategy was structured for the Lemaitre and Gurson models, from establishing a non-linear system of equations using an implicit integration algorithm and solving the non-linear equation system using the Newton-Raphson method. When assessing the numerical and experimental results, it was observed that the cumulative plastic strain at the fracture decreases with the increasing levels of the triaxiality ratio for both alloys and models. On the one hand, the Lemaitre model was more optimistic than the experimental results. On the other hand, Gurson's model proved to be more conservative in its prediction of ductile fracture. Regarding determining the fracture onset, in general, both models showed good predictive capacity. However, the numerical results for the aluminum alloy presented more in agreement with experimental data than for the AISI 4340 alloy. In the end, assuming the determination of the level of displacement at fracture, the Gurson's model has the best performance. In this sense, for a high level of triaxiality ratio, the Gurson porous material can be recommended to describe the mechanical behavior of the material at fracture. [ABSTRACT FROM AUTHOR]

The Ball Mill Abrasion Test (BMAT) is a laboratory experiment used to measure the resistance of materials under high-stress abrasion conditions. This test, however, has yet to be standardized. In this work, statistical theory determines the optimal number of spheres per material to be included in BMAT. This theory and the optimization method presented in this paper show that the optimal number of spheres for the usual experimental conditions is six. Finally, it is shown that if the optimization process is extended over a broader range of experimental conditions, the optimum number of spheres per material is also six. [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]

Enterprise resource planning systems (ERPs) have become an essential management tool for large and small companies alike. Although several papers on ERPs have been published in recent decades, only some studies have focused on user satisfaction during post-implementation. Based on the theories of technological acceptance and task-technology fit, we examine how the interrelationship of individual attitudes and matching between task and ERP affects user satisfaction in a public university that adopted an SAP-ERP. We distributed a questionnaire and analyzed the responses of 126 users using a partial least squares structural equation modeling (PLS-SEM model). Results show that perceived utility and overall benefits significantly predict user satisfaction. Moreover, overall benefits are influenced by the perception of efficiency in the task, improvements in coordination, and strategic alignment. Customization of the system had no statistical effect on the model. [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]

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]

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 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]

Queuing theory is a set of mathematical models that explain systems where customers wait in a row to receive service under specific selection criteria. The models allow analyzing the system's behavior and finding a "solid-state" that achieves an optimal use of resources. However, there are no models developed for each type of behavior of the distribution of customer arrival times or customer service times in the system in many real situations. In these cases, it is recommended to work the queuing systems through simulation by discrete events. This paper proposed applying the queue system principles in a container loading and unloading process in the port of Barranquilla (Colombia). For this, the entry and exit elements of the import and export processes of goods were identified. Each process's actual loading and unloading times were consolidated and analyzed to identify the most adjusted probability distributions for these times. The simulation process included the random generation of the times between arrivals and the service times to 30 simulations made in each process to study the evolution of the queuing system over time. The results demonstrated the utility of the proposed approach to obtain and analyze the performance measures of the processes. [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 progress of Information and Communication Technologies has significantly promoted the relationships among people of different geographical regions. Under this novel context, new settings of software development teams arise, known as virtual teams. The objective is to identify, evaluate and synthesize reported research about the measurement of interpersonal trust (IpT) in virtual software teams (VST). We conducted a systematic review of the peer-reviewed literature published in the research area until July 2019. We reviewed 747 papers, of which 11 primary studies were considered relevant for the investigation. Most studies (8 of 11) use instruments of direct measurements (interviews and questionnaires) to measure interpersonal trust. Studies that use indirect measurements focus on different characteristics of the virtual software team (agreeableness, affective lexicon, delegation, positive tone, acceptance of knowledge, etcand others). Recomiendo: Most studies (10 of 11) report that interpersonal trust measurements improve performance aspects of virtual software teams. Among them the willingness to share information, goodwill towards others, motivation, collaboration, and effectiveness. Most studies use questionnaires or interviews, but we believe that software repository mining to obtain IpT levels will be an auspicious research trend in the future. The attribute more used to assess IpT is the developer opinion. Other attributes used are emotions, interactions between developers, biography, acceptance of knowledge, and assignment of tasks. IpT measurement is a useful tool for decision-making in VTS management, especially in agile software processes, but there is little evidence of its use. [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]

Software programming for concurrent execution is not a simple task. The main issue related to this work is the lack of visibility of the multiple and parallel execution over the threads. Multi-core processor technology is a reality nowadays, and the only way to use modern hardware at its full capacity lies in the use of concurrent software. In this paper, a new 3D framework is presented, based on hand gestures that manipulate multiple threads of execution and deal with the visibility issues, using a 3D programming environment, including a set of experiments to evaluate the methodology's performance. [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]

This paper aims to present a Business Intelligence dashboard with a goal-oriented approach. A case study was developed taking as context of analysis a Cuban college. The requirements of the dashboard were modeled by using aspects of social modeling and the language i*. The models obtained allowed analyzing the goals, tasks and resources necessary to accomplish the requirements of the dashboard, as well as to align the metrics of the dashboard with the goals of the decision-maker. The resulting dashboard allowed visualizing and monitoring the performance of students to support decision-making at a tactical level. The contribution of this paper is a goal-oriented approach for modeling the requirements of dashboards and for extracting the metrics of dashboards aligned with the goals of decision-makers. [ABSTRACT FROM AUTHOR]

This paper presents the development of a modular mobile robot platform for multiple purposes and its adaptation into a beach cleaner setup. The robot has a robust construction allowing it to endure several sorts of environments. In the presented configuration, the developed robot is able to autonomously collect cans using an excavator-like claw. In addition to detailing the system's design and construction, this paper presents the description of the developed embedded electronics modules, a motor closed-loop speed control system and the optical flow algorithms that allows the computer vision system to detect and avoid obstacles and track the cans to be collected. [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, 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]

Hospital readmission is considered a key research area for improving care coordination and achieving potential savings. This is important because hospital readmissions can have negative consequences in terms of good health and recovery for patients. It is thus important to significantly reduce such readmissions. Unfortunately, there isn't a one-size-fits-all solution to preventing hospital readmissions. There are many variables outside of hospitals' direct control, such as social determinants and patient lifestyle factors, impacting readmissions. Although several studies have been undertaken to investigate 30-day readmissions, predicting revisits in shorter intervals (e.g., within 15 days after discharge) is highly needed to capture hospital-attributable returns better and develop more effective improvement plans. Hence, the aim of this paper is three-fold: i) to develop a comprehensive experimental study for identifying factors affecting 15-day readmission risk, ii) to classify patients according to the risk of 15-day readmission using logistic regression, and iii) provide general recommendations to reduce the 15-day readmission risk considering different predictors. To this end, the patients' characteristics were first described. Then, the significance of potential predictors, their interactions, and their effects were assessed. After this, a logistic regression model was derived to predict the likelihood of 15-day readmission in each patient. Finally, general recommendations were provided to reduce 15-day revisits. A real case study in Colombia was considered to validate the proposed methodology. [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]

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]