Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Context: The most important macroscopic variable of pedestrian flow is walking speed, this analyzes the behavior and operating conditions of a facilitie. In the present study, we established whether there is a statistically significant difference between temporary mean speeds for three types of infrastructures and two types of users. Methodology: We measure the time it takes a pedestrian to travel a pre-established distance in each of the 3 contemplated facilities: stairs, platform of a pedestrian bridge and a sidewalk on a level grade located in the city of Tunja, Colombia, we classify to users according to gender and direction of circulation. Results: The mean temporal velocity on the stairs, for women, is 0.81 m / s upward and 0.72 m / s downward. As for men, the mean temporal velocity was 0.81 m / s in both directions of circulation. In relation to the platform and the sidewalk, we find that the temporal average speed of women is lower than that of men. Conclusions: In the upward movement direction, we find that there is no statistically significant difference between men and women, otherwise, to what is established for the downward movement direction. Comparing the temporal average speed determined for the two sections of the pedestrian bridge, with the temporary average speed of the sidewalk, we find that there is a statistically significant difference, which is why it is necessary to characterize the behaviors separately in each section at the time of designing. or do work at a pedestrian facility.

Context: Thomas Malone defined collective intelligence at the opening of the MIT Center for Collective Intelligence in 2006 as "groups of people who collectively do things that appear intelligent" (Glenn 2015). The center indicates that its mission is to investigate How can people connect? so that, collectively, they act smarter than individuals individually. This research designed a multiagent simulation model whose objective was to represent the collective intelligence (CI) genome proposed by (Malone et al. 2010), in an environment with emergent situations in which a hierarchical organization coexists, in order to explore different configurations of external variables. and internal to organizations that allow maximizing the use of resources. Methodology: A multiagent simulation model is proposed that includes stochastic elements to model the behavior of agents and their interactions, which are not known exactly. The proposed methodology presents five stages: 1) conceptualization, 2) definition of requirements, 3) analysis and design, 4) coding, and 5) testing and validation. For the verification, tuning and validation process of the simulation model designed, two of the genomes documented by (Malone et al. 2010) were represented in the Wikipedia case. The first corresponds to the edition of individual articles, this genome was used to adjust the variables that intervene in the model in order to maximize the use of resources in organizations; the second genome corresponds to how an article is included in the general collection of Wikipedia, this case was used to determine the degree to which the simulation model designed corresponds to the representation of the methodological model proposed by (Malone et al. 2010). Results: Considering that the Wikipedia cases documented by (Malone et al. 2010) are theoretical cases, it was defined that the situation to be analyzed in the contrasting of the methodological model with the designed simulation model was the intelligent collective behavior in the organization that contained the genome of CI, this in terms of making better use of available resources to take advantage of ideas-opportunities or mitigate threats. From the tests carried out to determine the degree of correspondence between the models, it was evidenced that in 70% of them the percentage of use and mitigation was above 50%, hence it was concluded that the simulation model designed corresponded to the representation of the methodological model of the CI genome proposed by (Malone et al. 2010), in accordance with the business case studies. Conclusions: The simulation model designed contributes to the understanding of the methodological model and to the exploration of different configurations of the CI genome that allow to evaluate characteristics that the intelligent behavior of a business organization grants. Methodology: A multiagent simulation model is proposed that includes stochastic elements to model the behavior of agents and their interactions, which are not known exactly. The proposed methodology presents five stages: 1) conceptualization, 2) definition of requirements, 3) analysis and design, 4) coding, and 5) testing and validation. For the verification, tuning and validation process of the simulation model designed, two of the genomes documented by (Malone et al. 2010) were represented in the Wikipedia case. The first corresponds to the edition of individual articles, this genome was used to adjust the factors of the model in order to achieve the intelligent behavior of the organizations, in terms of the use of resources; the second genome corresponds to how an article is included in the general collection of Wikipedia, this case was used to validate the simulation model developed and verify that it properly corresponds to the representation of the methodological model proposed by (Malone et al. 2010). Results: Of the 80 tests initially carried out to verify and tune the simulation model designed, it was evident that in 48% of the configurations, the organization that contains the CI genome has higher levels in terms of making better use of the available resources . From these results and taking into account that the eight variables involved were significant for the simulation model, it was determined to carry out new tests in which three of the variables were assigned different values or levels in order to maximize the variable of response, while the rest of the variables were kept constant. For this purpose, it was decided to configure an optimistic scenario, another with trends and a pessimistic one; the configuration of each of them was based on the factorial diagram of main effects obtained from an experimental design carried out initially. The tests carried out for each of the scenarios showed that in 70% of the optimistic scenario configurations, the organization that contains the CI genome has higher levels in the response variable, in the case of the pessimistic and On trend, this behavior occurs in 77% and 81% of the configurations, respectively. These results confirm that the organization configured with the CI genome faithfully represents a behavior that collectively seems intelligent in terms of making better use of available resources compared to the behavior of the hierarchical organization. Conclusions: Of the tests carried out in the optimistic scenario, the highest value of resource use reached by the organizations was 496 for the one configured with the CI genome and 270 for the hierarchical one; of those made in the trend scenario it was 572 and 168, respectively; and of the pessimistic scenario it was 240 and 133. These results allowed determining that the trend scenario was the one that provided the best results in terms of maximizing the response variable; therefore, the configuration proposed there was the one taken as the starting point for the validation of the designed simulation model. From the validation of the simulation model developed, in which one of the genomes documented by (Malone et al. 2010) was taken for the Wikipedia case and configured with the values defined for each variable in the trend scenario; It was shown that in 100% of the tests, the organization that contains the CI genome has higher levels in terms of making better use of the available resources to adapt to changes in the market and disturbing environments compared to those obtained by the organization. hierarchical; In addition, the maximum value reached by the response variable for the organization configured with the CI genome was 887, while for the hierarchical one it was 171. Based on the foregoing, it is stated that the developed multiagent simulation model faithfully represents organizations that operate under the collective intelligence genome model proposed by (Malone et al. 2010).

Objective: In the design of a robotic hand prosthesis, a variety of problems arise for which there are multiple solutions proposed in the literature. One of them is the selection of a strategy for the automatic control of the movement of the hand. Within the functionalities of a prosthesis, the power grip functionality is one of the most important. Given the wide variety of proposals in terms of control techniques for power grip, the designer is faced with the dilemma of which of them is the most suitable for his particular design. Although there are metrics to quantify the quality of the grip, those that have been proposed address various aspects independently, which does not allow making a decision about the best option for the particular case. In this work, a method is proposed to calculate a composite indicator that allows the evaluation of the performance of control techniques in the power grip based on the following individual metrics that evaluate different aspects in the execution of the power grip: finger strength, grip strength, grip efficiency, grip cycle time, slip resistance, following error, and transient response overshoot. Thanks to the method proposed in this work, the question is answered: of several control options to be tested, which one offers better functional performance? Methodology: A set of metrics are adopted with which to obtain quantitative data related to the quality of the power grip and to the performance of the control target to govern the prosthesis; subsequently, selected individual metrics are calculated for each of the grip control techniques to be evaluated on a virtual environment, consisting of a robotic hand and an object to be grasped; then two composite indicators are constructed to obtain a quantitative assessment of the quality of the grip based on a statistical analysis, and the results are contrasted against the individual metrics used. Results: A method is proposed for the construction of a composite indicator, which allows the evaluation of the performance of control techniques, in power grips in robotic hands. By implementing this method, the best performance values were found in hybrid controllers. Conclusions: In this work, a method has been proposed to facilitate the decision-making of the designer regarding the most adequate control technique, among several available, to achieve the power grip with a specific prosthesis. The method seeks to build a composite indicator that groups together various metrics to evaluate particular grip functionality, and also to quantify the achievement of following instructions, facilitating decision-making about the incidence of the control technique in the achievement of the final objective. Financing: This work was supported by University of Cauca under the Master of Science in Automation program.

Objective: This research aims to reduce Portland cement contents in concrete by using small amounts of additives as an Industry-University partnership strategy towards a circular economy of concrete in Medellín, Colombia. Methodology: Using a multilevel factorial statistical model, mortar mixes were prepared with two different super-plasticizers: additive 1, based on policarboxilate; and additive 2 based on naftalene. Samples were evaluated at 7, 14, 21, and 28 days of curing via compression tests. The aforementioned model was implemented in order to study the influence of additives on the cement mortar mix. The microstructure was analyzed with x-ray diffraction and scanning electron microscopy. Results: The results revealed that both additives improved workability. Additive 1 showed better overall properties, which is why this research focused on it. Conclusions: Additive 1 (based on polycarboxylate) reduces the water-to-cement from 0,485 to 0,38, which corresponds with a cement reduction of 7,3% and a water reduction of 27,3%.

Objective: To morphologically analyze, by means of scanning electron microscopy (SEM), agglomerated boards made from rice husk and Hidropul 400, as well as boards made from wood fibers and glue. Methodology: For each 7,3 x 3,6 x 1,5 cm test piece, two samples were taken from the external and internal sections of each one of the boards to be analyzed. Thin-layer graphite coatings were made to each one of them, and, by means of SEM, micrographic shots were obtained in the range from 50x to 2000x. Results: It was evidenced that the panel made from rice husk had damage to its internal structure due to its porosity, the waxy layers of its coating, the high presence of silica, and the presence of water inside the adhesive, showing irregularities in adhesion between particles and low mechanical properties. Conclusions: Although the studied rice husk panel did not achieve the adequate structural properties, it has great applications for interior design. Additionally, due to its porous structure, its potential as a sound-absorbing material is considered. In the same way, the material can be improved by pre-treating the husk or combining it with other, more woody plant fibers such as wood waste, bamboo, coconut fiber, among others. Metodología: Se tomaron dos muestras por probeta de 7.3 x 3.6 x 1.5 cm en las secciones externas e internas por cada uno de los paneles a analizar, se realizaron recubrimientos de capa fina de grafito a cada una de ellas; por medio del microscopio electrónico de barrido se realizaron tomas micrográficas en rangos de 50x a 2000x. Resultados: Se evidencio que el panel fabricado con cascarilla de arroz, presentaba afectaciones en su estructura interna, debido a la porosidad, a las capas cerosas de su recubrimiento, a la alta presencia de sílice y la presencia de agua dentro del adhesivo, mostrando irregularidades en adherencia entre partículas y bajas propiedades mecánicas. Conclusiones: Aunque el panel a base de cascarilla de arroz estudiado no obtuvo las propiedades adecuadas estructurales, tiene grandes aplicaciones para el diseño de interiores, además por estructura porosa se consideran su potencial como material absorbente del sonido. De igual forma se puede mejorar el material al hacer un pretratamiento de la cascarilla o combinar con diferentes fibras vegetales más leñosas como desperdicios de madera, bambú, fibra de coco entre otros.

Context: The magnetic properties of rocks may reflect the modal abundance, composition, and microstructure of the magnetic grains contained within them, usually in a very small proportion. Magnetic Barkhausen Noise (MBN) is a non-destructive technique applied to magnetic materials, and it is very sensitive to microstructure and residual stresses. In this work, measurements of MBN in samples of rocks extracted from nature and containing varying proportions of magnetite were studied and analyzed. Method: Measurements were taken by magnetically exciting the cylindrical samples, using a magnetic yoke and measuring the induced field inside the rock as a consequence of the excitation. For the detection, a sensor coil placed on the excited surface on one of the flat faces of each cylinder was used. The signals obtained from the MBN were digitized, and a digital 5-200 kHz Butterworth filter was applied, calculating the root mean square (RMS) values. Results: The linear fit of the MBN RMS values with the increasing percentage of ferromagnetic minerals showed an increasing trend with a moderate correlation. A correlation between coercive force and the MBN RMS values was observed only for samples with abundant magnetite (> 25 vol%). Conclusions: An increasing variation of the RMS values of the MBN signals was observed in relation with coercive force for abundant magnetite samples. This may be related to the geological processes involved in magnetite genesis. Method: The measurements were made exciting magnetically the samples (cylindrical shapes), using a magnetic yoke and measuring the induced field inside the rock as a result of the excitation. For the detection, a sensor coil placed on the excited surface on one of the flat faces of each cylinder was used. The signals obtained from MBN were digitized. A digital 5-200 kHz Butterworth filter was applied and the RMS (Root Mean Square) values were calculated. Results: The linear fit of the MBN RMS values with the increasing percentage of ferromagnetic minerals showed an increasing trend with moderate correlation. A correlation between coercive force and MBN RMS was observed only for samples with abundant magnetite (> 25 vol%). Conclusions: A variation of the RMS values of the MBN signals was observed in relation with coercive force for massive magnetite samples. This can be related to geological processes involved in magnetite genesis.   Keywords: Rocks, Magnetization, Barkhausen Magnetic Noise, Non-Destructive Test.  

Context: Today, the usage of large amounts of data acquired from various electronic, optical, or other measurement devices and equipment brings the problem of data analysis at the time of extracting the aimed information from the acquired samples. Where to correctly group the data is necessary to obtain relevant and accurate information to evidence the physical phenomenon that you want to address. Methodology: The work presents the development and evolution of a five-stage methodology for the development of a data grouping technique, using machine learning techniques and artificial intelligence. It consists of five phases called analysis, design, development, evaluation, and distribution, using open-source standards, and based on unified languages for the interpretation of software in engineering. Results: The validation of the methodology was developed through the creation of two data analysis methods, with an average execution time of 20 weeks, obtaining precision values 40% and 29% higher with the classic data grouping algorithms of k-means and fuzzy cmeans. Additionally, there is a massive experimentation methodology on automated unit tests, which managed to group, label, and validate 3.6 million samples accumulated in the total of 100 group runs of 900 samples in approximately 2 hours. Conclusions: Finally, with the results of the research was determined that the methodology intends to guide the systematic development in specific problems in quantitative databases, such as the channel parameters in a communication system or the segmentation of images using the RGB values of the pixels. Even when software is developed both hardware, the execution will be more versatile than in cases with theoretical applications.

Context: Small and medium enterprises (SMEs) are critic for economic development and job creation in Colombia, as a developing country. Specifically, those in the IT consulting subsector produced the highest profits in the technological area, according to the 2015 records (Ministerio de las Tecnologias de la Informacion y las Comunicaciones de Colombia, 2015). However, despite their growing rate and huge impact, one of the main factors that affects their problems is the selection of the project management method; actually, authors as Campanelli and Parreiras show a remarkable trend into the agile frameworks adaptation inside the companies (Silveira Campanelli & Silva Parreiras, 2015). Also, Whitney and Daniels, strengthen the idea of the potential that have the agile framework on IT projects due to its flexibility when changing situations appear with respect to predictive methods (Whitney & Daniels, 2013). Method: For the development of the research, it was proposed, to characterize and define the common critical aspects of the managed projects, correlate the common critical aspects identified, with agile frameworks in project management, design an agile model in project management for IT consulting SMEs in Bogotá and finally Validate the model developed. Result: As a result of the research carried out, the model for IT consulting SMEs in Bogotá was designed and validated, on a project developed by one of the companies in the representative sample, which met the characteristics of the study, on which a percentage was observed improvement of 77%, over time, 57% in costs and its scope was not affected, complying with what the client requires. Based on the results obtained when implementing the developed model. Conclusions: It is inferred that by implementing the model in the projects developed by IT consulting companies in Bogotá, they can have satisfactory results in the development of their projects, in terms of time, cost and scope.

Context: The present research is related to the number of publications and citations in computational science in South America in the last twenty years. The measurement of scientific production is of great impact in order to evaluate the production of a country, as well  research groups, authors and university centers, among other aspects. Method: The research is classified as a longitudinal descriptive comparative study. The information was collected from the SCImago Journal & Country Rank platform, where the variables evaluated correspond to the different topics related to the area of computer science. The statistical processing of the information was carried out by means of the cluster technique, multivariate analysis of variance (MANOVA), Biplot analysis by the Procrustes method, complemented with the nonparametric technique of Spearman. The SAS University statistical package was used. Results: Brazil is statistically different from the other nations of the southern part of the American continent in terms of scientific dissemination in the area of computer science. There is a directly proportional relationship between the different topics evaluated, the highest correlation between nations was between Argentina, Brazil, Chile and Venezuela. Conclusions: Brazil is the South American country with the highest number of publications and citations in the different areas of computer science, followed by Argentina, Colombia and Chile, where the topic with the highest impact corresponds to applied computational sciences and the lowest is related to human-computer interaction.

Objective: This paper presents a methodology to determine the zones and elevated structures with the highest number of lightning strikes (Hotspots) in Barrancabermeja and Yondó. Methodology: It starts from the division of the surface of these two municipalities into polygons of 600 meters. In this way, using the information of lightning activity (cloud-ground impacts) provided by the Colombian Network for Total Lightning Detection LINET between January 2016 and February 2020, the number of impacts per polygon was determined, which made it possible to identify the hotspots in the study areas. Likewise, elevated structures such as transmission towers, telecommunications antennas and buildings were identified and located and a radius of influence of 300 meters was established for each one of them taking into account the mean error of location of the LINET network. In this way it was possible to determine the twenty structures with the highest number of lightning strikes. Results: The polygones with the highest lightning activity were found, of which 34 are located in Barrancabermeja and 235 in Yondó, which is consistent with maps of Density of Discharges to land made in the area where there is an increase in the number of flashes per square kilometer per year in Yondó compared to Barrancabermeja. 616 elevated structures were located in the municipalities of Barrancabermeja and Yondó, of which the twenty with the highest number of lightning strikes were chosen, which correspond 50% to transmission towers, the structure with the highest number of impacts being a transmission tower of 70 meters high located on the border of the two study municipalities with a total of 68 impacts. Conclusions: Of the 27 elevated structures found in Yondó, only 6 are located in a hotspot, which shows that in this municipality the presence of an elevated structure does not guarantee a hotspot and that the sites with the highest lightning activity are not influenced by the presence of elevated structures. Now, in the case of Barrancabermeja, 10 elevated structures were found in one of the hotspots, of which 7 are located in the urban area where 9 hotspots were found, from which it is inferred that in this municipality the urban planning and the presence of elevated structures, indeed increases the lightning activity. Financing: Universidad Industrial de Santander.