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In this paper, new models for credit risk prediction in Colombia are proposed by using different artificial intelligence techniques. These models can be used to support the risk management area in banks, and they aim to identify clients that could be in default, generating a possible credit risk for financial institutions. Three techniques are used to obtain the models (neuronal networks, decision trees, and support vector machines) that predict the next payment of a client's fee based on basic data from the client and previous recorded installment payments. Decision trees turns out to be more accurate than the other techniques that have been used when predicting credit risk with a ROC area of 88.29%. The proposed models reach accuracies that are like some other papers in the state of the art and in some cases, they overcome models in other studies. [ABSTRACT FROM AUTHOR]

This paper introduces the design, construction, and static testing of a solid rocket motor. The design was based on the solid rocket motor design methodology (SRM). The rocket motor included the igniter system, the combustion chamber, the solid propellant, and the nozzle. The internal diameter of the combustion chamber and the total length of the rocket motor were 27,67 mm and 230 mm, respectively. The rocket motor nozzle was of the convergent-divergent Laval type. The propellant was based on the mixture of potassium nitrate (KNO3) (oxidant) and high purity sugar (or sucrose: C12H22O11) (fuel), whose synthesis was achieved through a thermal fusion process (150-170 °C for 20-25 min). The performance of the rocket motor was evaluated using a static combustion test; resulting in a maximum thrust force (load) of 227 N, a total impulse of 98,69 Ns and a specific impulse of 65,8 s, thus allowing its classification as a class G rocket motor. The results obtained are considered of great importance in the development and characterization of solid rocket motors, necessary to promote the experimental rocketry in Colombia. [ABSTRACT FROM AUTHOR]

With the technological advance in electricity generation techniques and the prevailing need for sustainable development of countries, the massive use of alternative energies has been in force for the last 15 years, with clear goals towards 2020 for sustainable development. At the regulatory level, Colombia cannot be left behind in the regulation, and progress has already been made on the subject with law 1715 of 2014 and several decrees of incentives in the promotion of renewable energies. The objective of this paper is to show the state of the art on the way in which the net balance and residential energy self-consumption by DER is handled by several tax regulations in different countries of Europe; moreover, it will also go into detail about the advantages offered by using a selected methodology to consider fair charges of support for the use of the electrical network by generators distributed from photovoltaic solar energy, all this as a contribution to advances already made in this field. This is provided from a network planning approach, in which a long-term methodology is selected that efficiently integrates the distributed generation into the interconnected system and allows transition periods in its implementation to avoid disruption of network operators (ORs). Likewise, this analysis is supported by the simulated operation of a system with DER together with the changes in load flows due to decongestion and surplus injection that the electric system has in the scenario of massive use of these resources. [ABSTRACT FROM AUTHOR]

Natural stone has been an important element in Colombian construction since the hispanic period, especially in Bogotá city capital from Colombia. Sandstone and limestone rocks are ornamental and structural elements on heritage buildings and new constructions, and their use is important to revitalization of urban spaces for the enjoyment of the population. This paper shows the results of some technological characterization tests of two rock types widely used in construction, commonly known as Piedra Muñeca or Piedra Bogotana and Marmol Royal Bronce, used in historical buildings as well as modern ones. Petrophysical and mechanical properties of these rocks identified in a preliminary way were: Petrographic analysis, physical properties (bulk density, bulk porosity and water absorption), compressive strength, flexural strength, weathering resistance and impact resistance, as shown in the Brazilian technical standard ABNT NBR15845. The obtained results allows to determine, in an early way, that the two varieties (yellow and pink) of the Piedra bogotana stone can be used as a structural element (walls, columns, beams and foundations) and also as a dimension stone for buildings, floors and squares. It´s recommended the use of yellow variety specially on interior spaces. Marmol Royal Bronce can be used in finishes and also in any type of facing, floor and as a structural element in highly traffic streets. [ABSTRACT FROM AUTHOR]

This paper presents a mechanism to cooperation in large scale resource social dilemmas. The mechanism was developed considering the Colombian electricity crisis (1992-1993). The paper offers a dynamic hypothesis as extension of the small scale resource social dilemmas theory to large scale situations that integrates the effects of delays, expectations, and perceptions about cooperation. This work also presents simulations that suposes the dynamic hypothesis as explanation of the variation of the electricity demand in the 1992 1993 Colombian electricity crisis. The results explain also the variation of demand after and before shortages in that crisis. As a conclusion, we suggest that perception, and expectations in dynamic complexity situations should be considered as a fundamental issue for explaining cooperation [ABSTRACT FROM AUTHOR]

In Colombia, try closing the digital divide has demanded incorporation perform various ICT strategies, "Computers for Schools" is one of them. ICT Ministry This program provides technology infrastructure to educational institutions and training for teachers to incorporate ICT pedagogical use, creating more favorable conditions for changing teaching practices, while promoting improvements in education and learning students. However, after years of intervention, is still in question: how evaluate "whether and to what extent" teaching practices changed in a "desirable"? This paper proposes an alternative idea for the evaluation of teacher training processes in ICT using a model that applied to extract evidence to answer that question and then promoted beyond mere appreciation of indicators, a deeper reflection on initial ICT training to teachers. [ABSTRACT FROM AUTHOR]

This paper presents the results of a research on Information and Communication Technology -ICT; it specifically focuses on computer use and knowledge of the Internet existence by vulnerable population. La Escuela Busca al Niño (EBN-Santa Marta) Project was selected as a context of research. This was operated by Universidad del Magdalena and was supported by Ministry of National Education, UNICEF, ECOPETROL and Santa Marta Council. The project aim was to provide care for children and adolescents in vulnerable conditions, outside the education system, and their families. In this study, a characterization of 2481 persons of family cores beneficiaries of project was done. The results showed that access levels to computers and knowledge of Internet existence was very low, highlighting that 94% of the population under study has not access to a computer and do not know about Internet existence. [ABSTRACT FROM AUTHOR]

Business intelligence is used to bring answers to problems related to access, availability and utility of information. This paper presents the process and results obtained in the construction of a business intelligence solution to support decision making in educational projects to vulnerable childhood population in the Colombian Caribbean region. The application context is the execution of a project named "Learning Circles", educational model operated by University of Magdalena since 2006, whose fundamental objective is to bring back to school to refugee and vulnerable children. To develop the solution we used as methodological guidelines Moss and Atre's model and the agile method named Extreme Programming. The main practical implication of this work is to show the usefulness of these technologies in different context to business. [ABSTRACT FROM AUTHOR]

This paper presents the results of stated-preference, discrete selection experiments designed to obtain quality indicators in the urban public transport service in the town of Barrancabermeja, which was raised to two alternatives that contain the attributes : fare, walking distance from origin to fate, waiting time at bus stop, travel time in vehicle, availability of seats, driver and vehicle, generating a Multinomial Logit model, which allows the city to complete study attributes most relevant to the quality of the service are: 32.6% rate, walking distance from the origin to the whereabouts 18.0% and 14.3% travel time. [ABSTRACT FROM AUTHOR]

In this paper, the authors present the most important considerations, achievements and contributions that they achieve through the experimental and theoretic analysis that they did about the methodologies to estimate the Ampacity Rating in Overhead Conductors propose to IEEE and CIGRÉ investigation groups. Additionally the authors present an analysis about the application of these methodologies in the Colombian's electrical service. [ABSTRACT FROM AUTHOR]

The methods for enhanced recovery of heavy oil by steam injection, present great inconvenience in reservoirs of over three thousand feet deep. This is due to the high losses of energy from the generator on surface to the wellbore, so, the oil can not reach a temperature at which it is mobile and can be produced. This paper proposes the use of steam generators at bottom, with the goal of inject wet steam into deep reservoirs. Subsequently, is proposes the application of the technique steam assisted gravity drainage (SAGD), and that because it uses short distances between wells, requiring low rates of injection, such as those that provide these generators. Finally, is assessed the feasibility of implementing enhanced recovery processes in deposits of heavy crude oil with characteristics similar to those of the Colombian Llanos Orientales. [ABSTRACT FROM AUTHOR]