The edition of scientific journals in Colombia is facing increasing challenges. Publindex has been generating spaces for editorial strengthening and changing its processes in order to tune the production of journals in Colombia with the highest quality international trends. This process faces the obstacles posed by the fact that the majority of scientific journals in Colombia, including ours, arose in a context and under a logic almost opposite to the current one.
Explosive Parameters for Coal Samples (Antioquia, Colombia)
Rafael Fuentes Chica, Jorge Molina Escobar, Astrid Blandón Montes
Through proximate analysis (residual moisture, RM, ashes, As, volatile matter, VM, fixed carbon, FC, total Sulphur, TS and calorific value, CV), granulometric, minimum cloud ignition temperature tests (TMIn), lower explosion limit (LEL) and explosion severity (Kmáx); it is proposed to identify which coal produces the most explosive dust.
For most samples, the highest amount of coal particle volume is between 100 μm and 200 μm. For the Amagá sample, the volume of particles smaller than 10 μm is the largest, which agrees with the results of the TMIn, which is the lowest (400 °C), the lowest LEL (30 g/m3) and the highest Kmáx value (176 bar, m/s). On the contrary, the Angelópolis sample presents a very skewed curve towards sizes between 60 μm and 300 μm, therefore, its TMIn is the highest (480 °C) of the Eastern Zone of the Sinifaná basin and its LEL is under 60 g/m3, and it also presents the lowest value of Kmáx (106 bar, m/s), thus, it is observed that there is a direct relationship between the granulometry and the results of severity and sensitivity to the explosion.
In general, there is a different behavior between the samples of the municipalities of Amagá and Titiribí, especially between the LIE and the results of the analyses of VM, FC and CV, with respect to the other samples, which is also in agreement with their greater susceptibility to inflammation and explosiveness.
Sustainable Housing, from a Theoretical and Public Policy Approach in Colombia
Diana Elizabeth Valencia
Social housing in Colombia does not include, as design parameters, environmental or social criteria, since financial closure is a priority. This is why the objective of this article is to propose guidelines for the design of prototypes of sustainable social housing (VIS), based on the application of the baseline matrix.
With respect to the methodology used, this research is based on the matrix elaborated in the research project called Proposal for Guidelines for the Architectural Design and Construction of a VIS Prototype for Medellín, which includes sustainability criteria in its design based on the baseline elaborated in phase II and applicable to Medellín and the Metropolitan Area. This matrix is composed of four thematic axes: site selection, rational use of water, materials and habitability. Once applied, the results served to define guidelines for intervention at the different scales.
The project resulted in intervention guidelines that can be applied in the design stage of this type of project or that can be used as a reference point to evaluate sustainability in VIS projects developed.
Study of Tensile Strength in Structural Anchors Post-Installed with Epoxy Adhesive
Diego Fernando Páez Moreno, Jeniffer Hamón Caicedo
Research carried out on post-installed structural anchors has shown a link between the embedded length and the diameter of the bore with maximum tensile strength. This paper, is the outcome of research funded by the research department of the Universidad Pedagógica y Tecnológica de Colombia, analyzes this link from the variation of resistance and failure type in structural anchor prototypes with variations in embedded length and drilling diameter, in particular compressive strength 28 MPa, epoxy adhesive, reinforcing bar, 15 graphite units of 0.007 m diameter, and 15 corrugated steel units of 0.0095 m diameter, for a total of 30 systems requested for direct traction in the universal machine. The results showed that tensile strength and failure type are a function of the embedded length and corrugated structure of the anchored reinforcing bar.
Use of Blast Furnace Slag and Steel in Asphalt Mixtures: Review
Hugo Alexander Rondón Quintana, Marcio Muniz de Farias, Fredy Alberto Reyes Lizcano
In the manufacture of asphalt mixtures, large quantities of natural stone aggregates are consumed, which has a negative impact on the environment. These aggregates can be partially or totally replaced by others that are disposed of in dumps and produced by steel companies, such as blast furnace slag (BFS) and steel (SS). These last two materials have chemical and physical properties that make them suitable for use in multiple applications such as road construction, maintenance and rehabilitation. The article presents a review of the state of knowledge of the use of BFS and SS in the production of asphalt mixtures, describes and defines both materials, presents the environmental problems, their toxicological risk of use, their chemical and physical properties, the advantages and limitations of use and the way they have been studied to be used as stone aggregates of asphalt mixtures. Based on the bibliographic review, the authors at the end of the article present some recommendations to continue the studies tending to substitute natural stone aggregates with BFS and SS in the manufacture of asphalt mixtures.
Floor Accelerations for the Design of Non-Structural and Structural Elements that are not Part of the Seismic Resistance System in Buildings
Ricardo E. Barbosa, José J. Álvarez E., Julian Carrillo León
The purpose is to evaluate the method used in the Colombian Earthquake Resistant Construction Regulations (NSR-10) to calculate the floor accelerations that are necessary to design non-structural elements and structural elements that are not part of the seismic resistance system. The study compares the maximum floor accelerations calculated with NSR-10, ASCE 7-10, UBC-97, Eurocode 8-04 and NZS 1170.5-04, with the maximum floor accelerations measured in specimens tested on a vibrating table, and in existing buildings during real earthquakes. The article also proposes a modification to the method currently used by NSR-10. The proposed modification generates a more accurate estimate of the accelerations needed to design these elements in medium and high-rise buildings. The proposed recommendations are based on the results of the evaluation of the method currently used in NSR-10, the procedure used in other seismic-resistant standards, experimental results measured in reinforced concrete structure models and accelerations recorded in instrumented buildings.
VS.Net Add-on for Optimal Definition of Black Box Software Testing Using Covering Arrays
Jaime Herney Meneses Ruiz, Eduar Alexis Peña Velasco, Carlos Alberto Cobos Lozada, Jimena Adriana...
Software testing can exceed 50% of the total cost of a software project, which is why companies need an alternative to reduce their cost and time of implementation. This research proposes the use of combinatorial structures known as Covering Arrays (CA) and Mixed Covering Arrays (MCA), which guarantee the detection up to 100% of errors with a minimum amount of testing. With this approach, a Visual Studio.NET add-on was developed for the optimization of the tests and its use was evaluated with students of last academic term of Computer Science Engineering and of a software company. The results obtained are promising and motivate the research group to disseminate its work at the national level. The research project was funded by the Vice-Principal Office of Research of the Universidad del Cauca.
Learning Methodology of Binary Number System Based on Discovery Learning Theory
Omar Ivan Trejos Buriticá
This article examines the possible changes in the autonomous learning of first academic term students of Computer Science Engineering from the application of the theory of learning by discovery, specifically in the assimilation, appropriation, application and feedback of the binary numerical system. The methodology used corresponds to the framework of qualitative educational research, articulated with a simple, individual and multiple case study. The research begins with the announcement of the learning theory to be used and ends with the evaluation and feedback between teacher and students based on the quality-quantitative results obtained. The Excel spreadsheet was used as a support tool and the group was segmented so that comparative criteria could be established between the traditional teaching methodology of the binary system and the methodology based on learning by discovery. The results show a more significant and meaningful learning on the part of the group to which the theory of learning by discovery was applied. In the same way, it was noted greater academic independence on the part of this subgroup of students and a greater confidence in relation to the approach of unknown topics but framed within the disciplinary knowledge proper to Computer Science Engineering.
Predictive/Adaptive Control of Complex Systems Using Neural Engineering Techniques
José Gallardo Arancibia, Claudio Ayala Bravo, Rubén Castro Castro
The design and implementation of a predictive/adaptive control system is presented, using neural engineering techniques to control a non-linear MIMO system in order to control, at a later stage, the temperature and level in a non-linear conical plant. Preliminarily, conventional control structures were tested, which gave rise to the need to test intelligent control structures that allow the control objectives to be met more effectively. The process begins with the experimentation of different neuronal control structures, and then escalates to a predictive/adaptive neuronal control system. The results achieved at the simulation level, testing the proposed design on mathematical models of non-linear MIMO systems, were satisfactory and met the control objectives established, therefore, in the next stage of the project, the experimentation is estimated in the real plant under study.
Prioritization of Deliveries in Manufacturing Companies Using Fuzzy QFD
Juan Carlos Osorio Gómez, Mayra Alejandra Peña Vega, Deysi Yulieth Arias Giraldo
The restrictions of installed capacity and distribution resources to which medium and large manufacturing companies are normally subject, make it necessary to establish methods that serve as a tool to make decisions regarding the prioritization of each of their warehouses at the time of supplying them. the importance that the distribution center assigns to each of these, is closely related to the conditions and particularities that characterize them, being these factors of a qualitative, quantitative or a mixture between the two. This article presents a fuzzy QFD multi-criteria method which, in addition to using quantitative variables to establish the order of dispatch of the finished product, considers qualitative variables, the result of the opinions that experts can offer about the particular situations of each winery by means of linguistic variables that are finally quantified through fuzzy triangular numbers.
The “Blame-Blame” Syndrome from a Systemic Perspective and Its Implications for Problem Solving in a Company
Jorge Iván Pérez-Rave, Favián González Echavarría
The objectives of the study are: to explore systemic structures of the “blame-blame” syndrome in a company, to describe methodologically a playful tool that helps to recognize and mitigate it, and to discuss its implications for causing analysis and problem solving. The ludic exposition includes case description, work team and location, observation scenarios (with and without blaming) and deployment in three test groups. Results are compared for both scenarios and causes of defective orders; percentage of defects and productivity are analyzed. Play can be used by teachers, consultants and trainers in general to confront learners in a simulated environment with and without the syndrome. It makes it easier to systemically reflect on the subject, to identify its signals and intervene before carrying out the cause analysis. This work provides theoretical and empirical elements about the benefits of eradicating the “blame-blame” syndrome in cause analysis, and proposes to consider it as a contingent factor in future studies.