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18

Authors: Andrés Roberto Díaz Pascuas, David Leonardo Torres Rodríguez, Astrid Rubiano Fonseca

Bone age estimation is a procedure used in radiology and endocrinology for diagnostic purposes regarding malnutrition and growth abnormalities. Its effective implementation requires professional experience and time in the field; therefore, it is very useful to develop computer-assisted tools to help automate the estimation of bone age. This paper is a literature review of models, methodologies and developments presented as aids to professionals in estimating bone age. It is organized chronologically, emphasizes the innovations made by each author to implement this process and presents the techniques that each of them applied in their development.

18

Authors: Carlos Felipe Urazán Bonells, Edder Alexánder Velandia Durán, Germán Alfonso Prieto Rodríguez

The increasing travel times in Bogota, resulting from a significant population increase and greater financial facilities for the acquisition of cars and motorcycles, has gradually complicated traffic in the city. This fact encourages the public to consider, in each particular case, the mode of urban transport that represents the best travel speed, based on the day, time, the urban area of origin and destination, the path length, the speed requirement due to work demand and the availability of means of transport. Depending on the above, the motorcycle is the fastest method, followed by the car and bicycle. In another group with average travel speeds under 15 km/h, we find collective public transport (CPT), the bus rapid transit (BRT) system and on foot. As travel distance increases, the motorcycle and car improve travel time, due to a higher driving speed. The motorcycle’s travel speed reaches 43 km/h during off-peak hours for travels between 5 and 10 km in length and global values indicate that its speed is 1.3 times that of the car.

20

Authors: Dayan Lizeth Parra Astudillo, Luis Javier Carrillo Puerto, Edder Alexánder Velandia Durán

Although citizens are guaranteed water supply in Bogota, it is important to develop strategies to encourage a reasonable use of the resource and thus prevent future shortage problems. This is a significant event for the future, if the alarming changes reported in the sources of water in the region are taken into consideration. Seeking to provide a savings strategy in water consumption, this paper proposes to install, in new residential buildings belonging to socioeconomic strata 3 and 4, a system for the use and reuse of greywater, in terms of ensuring a reliable supply in physicochemical and biological quality for users, as well as an investment in infrastructure for easy operation and economic viability. The purpose with this strategy is to obtain a lower price per cubic meter of greywater compared to the conventional aqueduct rates and, at the same time, reduce the monthly demand for drinking water per user.

22

Authors: Pedro Fernando Martín Gómez, Oscar Saúl Hernández Mendoza, Juan Sebastián Toquica Arenas

For the past few years, agriculture has had a special development of new technologies for the welfare and sustenance of human beings. New technologies in agricultural automation have been developed through multiple investigations based on the efficiency and effectiveness of common agricultural practices, together with modern production equipment and methods. In this vein, this paper describes the design and simulation of an autonomous vehicle for smart irrigation of fertilizers in test crops, reason why a specialized software is used. Thus, a new perspective is generated about how robotics and automation can provide a different and effective solution to the way crops are handled as rows in Colombia, depending on whether they are more technically advanced and consistent with our topography and production characteristics. This vehicle seeks to facilitate the application of modern technology in agriculture, adapted to small and medium size crops, which represent a high percentage of agricultural production in the country.

34

Authors: Ana Sofía Figueroa Infante, Elsa Fonseca Santanilla

The article stems from the Sustainable Mobility project carried out at the Research Center for Sustainable Development and Climate Change (Cidescac)from La Salle University. Some nonbiodegradable materials were studied that could be recycled and reused as fissure sealants in asphalt pavements. The recycled materials were rubber from the used tires of vehicles and polystyrene (styrofoam) to improve the physical, mechanical and chemical properties of the asphalt mix. The tests performed included the physicochemical characterization of materials to find the optimum proportions of field application. Tests were analyzed in order to find chemical stability, plastic deformation, fatigue and the dynamic module of the designed mix. The scope of this phase of the research is the production, placement and follow-up of the new material to repair surface damage in flexible pavement, for which a test stretch granted by the Urban Development Institute was carried out.

10

Authors: Edgardo Jonathan Suárez Domínguez, Yolanda Guadalupe Aranda Jiménez, Elena Izquierdo Kulich

In this paper we determine the compressive strength of a type of poured earth made from mixtures of clay soil, loam soil and sand, stabilized with cement and lime. A mathematical model describing the resistance-time variation is proposed. It may be noted that two parameters are important for validating the compressive strength model: the final resistance at xx days, and, second, a constant related to the hardening rate of ground concrete

16

Authors: Milder Moisés Mengual Velásquez, Fabián Augusto Lamus Báez, Jenny Magaly Pira Ruiz, Sandra Elodia Ospina Lozano

Rigid polyurethane foam is a material that shows an excellent relationship between compressive strength and density. Besides, it can be mixed on-site, changing rapidly from liquid to solid, interesting characteristics that can be exploited in the construction of structural fills. This work studies the compressive behavior of composite materials in a matrix of rigid polyurethane in which segments of materials like Guadua angustifolia and rubber tire chips are embedded. Initially, different mixtures were designed, varying the content of each of the materials. Samples for each mixture were constructed to determine their resistance to simple compression and confined compression. Finally, the filler’s contribution to the resistance to radial compression was observed in cylindrical PVC elements. It was found that the addition of particulate Guadua to the polyurethane matrix allows to obtain a filler with higher resistance to compression than the matrix, which reduces by 95% the amount of polymer needed to obtain the same volume.

20

Authors: Fabián Augusto Lamus Báez, Carlos Felipe Urazán Bonells, Sofía Andrade Pardo

This paper proposes structural modules of Guadua angustifolia for the construction of pedestrian bridges as a solution to the lack of infrastructure in village roads and even in suburban areas.The proposed module can be used in the construction of arch bridges, suspension bridges, and floating steps. However, in this work, the module was designed to be used in straight truss bridges, since this is the configuration in which the bridge elements would be exposed to internal forces of greater magnitude. Element resistance was analytically determined by the method of allowable stresses. Subsequently, load tests were performed on full-scale specimens of the modules and structural elements. Using a numerical model, it was found that, following load specifications by the Colombian Code of Bridges, a bridge with a clear span of up to 21 meters could be constructed.

21

Authors: Luis Efrén Ayala Rojas, Cristian Rodrigo Bolaños, Cristian Camilo Jiménez

This paper presents the results obtained according to a comparison between the hydraulic capacities of ditches designed using Chezy-Manning and Darcy-Weisbach equations. For this purpose, efficiency and hydraulic performance of triangular-shaped ditches were determined using these two mathematical expressions in a physical model. This allowed to determine the criteria and tools for the design of an optimal structure, meeting the parameters required by existing regulations.

22

Authors: Jair Eduardo Rocha González, César Fernando Gómez Triana, Pedro José Sánchez Caimán3

This paper presents the methodology and partial results of the study to establish a model of the Shortest Path Problem (SPP) for terrestrial connection between geographical points of economic importance in Cundinamarca in order to improve tactical routing decisions. For this purpose, significant differences are established in terms of the computational performance of some mathematical techniques, which arise from a systematic review of similar problems in national and international contexts, through a contrast analysis between different techniques.

15

Authors: Fabián Augusto Lamus Báez, Sofía Andrade Pardo, Nancy Torres Castellanos

One of the limitations structural engineers face when designing a building and, in general, any structure in Guadua angustifolia Kunth is the lack of technical information related to the parameters needed for a proper numerical model of the same. The degree of embedding that can provide support to its structural element is an important variable during structural modeling, because the judgment of the engineer in the selection of this parameter for modeling can influence the rigidity of the structure and, therefore, its period of vibration. This paper presents the experimental results of the constant of rigidity of a connection between a Guadua angustifolia Kunth column and a concrete element that is part of the foundation, when the column is under monotonic lateral loads. Additionally, the impact of each component of the connection on the rigidity of the structure has been evaluated.

18

Authors: Guillermo Armando Briceño Vanegas

In 2010, we carried out a comprehensive ecological characterization of landscape units present at the San José de Matadepantano Ranch, in the Casanare foothills. Landscape units were divided into natural and cultural. Natural units were classified into five categories: savannah, flooded savanna and marsh, gallery forest, palm field, and relict forest. Cultural units were classified into four categories: changes in land area, vector changes, low impact constructions, and constructions with high impact. All units were mapped based on aerial photography, and coverage area was calculated by analyzing the dynamic trends of each. Natural landscape units with more coverage area were savannah and gallery forest, while the construction of the university campus of the Utopia project constituted the major cultural transformation of the land. In regional context, gallery forest showed a high degree of structural continuity and ecological integrity, compared to the surrounding farms, although with some sections affected by anthropogenic disturbances. The two main water currents running through the farm, the brooks named Tiestal and Güio, does not appear to have disturbances that jeopardize their ecological integrity, but it is necessary to await the outcome of detailed ecological surveys, currently under the way, to confirm the findings of this comprehensive study.

21

Authors: Nathaly Murcia Sepúlveda, Jenny Andrea Suárez Barbosa, Salvador Pacheco, Jaime G. Barrero Pérez

This paper presents the design and implementation of two adaptive filters (Wiener filter and LMS [least mean square] filter), in order to remove unwanted signals in a desired or reference signal. These adaptive filters were programmed in the PSoCTM (programmable system on chip) development system; and a virtual generator was developed by the LabView™ computational tool. The data generated were used as inputs to the filter system and formed the basis of the process carried out. Similarly, the article describes the tests and the analysis of each filter type under different noise conditions for a final comparison of the results

25

Authors: Diana Milena Díaz Hernández, Andrés José Alfaro Castillo

This paper presents seismic hazard maps of Colombia for a return period of 475 years. These maps are evaluated with probabilistic seismic hazard methodology, with a seismic catalog for 1960-2012, for which five equations of the 2008 Next Generation Attenuation Relation Project (NGA) were used. The NGA equations generate results with large variations, despite using the same relation scheme and the same PEER database, which was filtered depending on the criteria of each group. Additionally, standard deviations play an important role in the evaluation, because, in some cases, the value exceeds the average. Although we did not perform an analysis of completeness, the values obtained for the cities of Cali, Ibagué, Medellín, Pasto, Pereira, Popayán and Quibdó are greater than the current seismic standard.

28

Authors: Diana Jimena López, Juan Martín Velasco, Óscar Amaury Rojas

The Enterprise Actor Model (MADE) is the product of five years of research by the research group in development in Industrial Automation at the University of Cauca, Colombia. It is a model of enterprise integration developed specifically for production-sector businesses. It aims to represent the structure, behavior, organization and integration of the components of a production business, while establishing the information that flows among them. Achieving a successful application of this model to a particular production business would become a major contribution to the field of automation and enterprise integration. A series of works has developed around MADE that gradually allowed to add new features, definitions and concepts; however, the degree of formalization required to initiate the process of developing a methodology for implementation has not yet been achieved. This article focuses on formalizing the existing components of the Enterprise Actor Model which results in three basic elements of MADE: entities, nomenclature of entities, and models.

12

Authors: Rodrigo Buitrago, Luis Carlos Belalcázar

The present study shows the lifecycle analysis (LCA) for the production chain of bioethanol as a fuel (E100) in Colombia, using the OpenLCA free software. Data from bibliographic references and emissions stock from the Ecoinvent V2.2 database was used in order to carry out the emissions stock for the present study. The Global Warming Potential (GWP) was quantified using the IPCC 2007 impact methodology, and the demand of non-renewable energy was quantified using the cumulative energy demand (CAE) method. The activity that represents the greatest contribution to GWP is the production of fertilizers and its release to the environment as they are used in agriculture. As for the CAE, the process with greatest demand corresponds to the preparation of land and the production of fertilizers.

15

Authors: Linda Victoria Ariza, María Alejandra Sánchez, Juan Felipe Franco

The purpose of the present pilot study was to determine the citizens’ perception of the impact of air quality in Bogota in the health and quality of life of the population. For this, a citizen perception survey instrument was designed and conducted in 4 neighborhoods of the city, selected according to their air pollution conditions. Each survey was made up of 23 questions; 50 surveys were conducted in each neighborhood, for a total of 200 surveys. In general, more than 80% of the surveyed population perceives poor air quality in the city and acknowledge the negative impacts of this problem. In all neighborhoods and socio-economical levels, more than 50% of the population believes public transportation is the main source of air pollution, which evidences the importance of this emission source due to its closeness to people. Likewise, results show that the empowerment of citizens towards the city’s air pollution problem is limited, as the majority of the population does not identify the authority in charge of this matter in the city and does not recognize follow-up and control actions. This is a key element, taking into account that citizen participation in public policy processes can lead to the generation of collective actions towards a better environmental condition in Bogota

16

Authors: Claudia Patricia Dávila Pinzón, Aura Liliana Rojas Pérez, Néstor Yezid Rojas Roa

The purpose of the project was to estimate the emission of criteria pollutants generated by mobile sources in the Bogota-Facatativá road, using a bottom-up approach, for the vehicle fleet registered and quantified in the second semester of 2012, categorized in light vehicles, buses, trucks and motorcycles. Two methods of emission estimation were used: the IVE model and emission factors obtained in route for Bogota. Both methods show that the CO emissions mostly come from light vehicles and trucks, whereas NOX and PM mainly come from buses and trucks. The emission values are significantly different between the two estimation models, which suggests the need to refine the emission factors.

26

Authors: Diana Marcela Romero Cárdenas, Hugo Sarmiento Vela, Jorge E. Pachón

The present research assessed the presence of polycyclic aromatic hydrocarbons (PAH) and heavy metals resulting from the burning of sugar cane in the Cauca River valley. For this purpose, a subset of 240 samples was considered, integrated over 24 hours, of particulate matter of less than 10 microns (PM10), collected from October 2010 to February 2011 in the villages of Bolo San Isidro (highly exposed zone) and Ricaurte (control zone) located in the municipalities of Palmira and Bolivar. A chemical characterization related to the identification of HAPs belonging to the list of priority contaminants of the United States Environmental Protection Agency was carried out for part of the subset, following EPA T0-13A. In addition, the chemical characterization of metal compounds in 108 of these samples carried out was taken into account, in accordance with the EPA IO-3.1 method. The application of the principal components analysis (PCA), the factorial analysis with varimax rotation and a series of statistical correlations allowed the identification of the possible metals and PAH tracers of the burning of sugar cane. Results of the study show that the PAH associated with the PM10 originated in the Cauca River valley, possibly attributed to the burning of sugar cane in the high exposure zone, are: Pyr, Phe, and Flt, whereas the metals associated directly and indirectly with this source of emission are: Fe, Mn, Si and Cu.

28

Authors: Jorge E. Pachón

The Colombian Congress and International Conference on Air Quality and Public Health (CASAP) is the most important event in the country in regards to air pollution, a problem that represents high costs to the Colombian society, represented in morbidity and mortality episodes. The CASAP brings together scholars, researchers and public policy managers from around the country, making it a sample of the current level of investigation related to air quality (and related topics) and an opportunity to identify new fields of action. The document presents an assessment of the research on air quality in the country and some themes for consideration, with the aim to provide ideas that allow moving towards a comprehensive system for air quality management that guarantees a resource of adequate conditions for society at large.

14

Authors: Andrés José Alfaro Castillo

This article presents a probabilistic and deterministic assessment of a seismic threat in Neiva as of 2013, using the recent and robust attenuation equations corresponding to the Next Generation Attenuation (NGA) developed in the United States. These equations were proposed by Abrahamson and Silva, Boore and Atkinson, Campbell and Bozorgnia, Chiou, Youngs and Idriss. Regarding the deterministic assessments, conservative scenarios are presented, and considering a total rupture of the fault, the PGA would be of 550, 355, 305, 400 and 375 Gal due to the La Dina fault. These values are considered as the maximum credible seism. For the probabilistic analysis, due to the fact that the NGA equations are applicable to earthquakes with magnitudes between 5 and 8, the catalogue was drastically reduced. Therefore, a statistical analysis was performed with data of magnitudes between 4 and 7.2 and the catalogue was completed, assuming a Poisson distribution. The assessed accelerations (average plus a standard deviation) were 280, 230 280, 305 and 320 Gal, respectively.

18

Authors: Laura Marcela Zárate Polanco, Nury Alejandra Otálora Santamaría, Laura Ramírez Suárez, Lena Prieto Contreras, María del Socorro Cerón Lasso, Juan Carlos Poveda Pisco

Potato starch provides high functional characteristics in the elaboration of meat products. For this reason, three native starches of promising clones of a native Colombian yellow potato (S. tuberosum Phureja group) supplied by Corpoica and harvested in the town of Sibaté (Department of Cundinamarca) were evaluated in the elaboration of standard bologna. First, the starches from the three clones were extracted and functionally characterized. Then, three bolognas were produced using a total substitution of the starch in the formula by native starches, and a standard bologna with commercial potato starch. Then, three series of physicochemical tests were performed on the bologna, two series of texture tests and a sensory evaluation control test. The extracted starches showed an average gelatinization temperature of 70.7 °C, which guaranteed a stable emulsion during the scalding process. The bologna with native starches showed average protein (15.22%), fat (13.88%), starch (4.44%) and syneresis (8.83%) values, which were aligned with Colombian Technical Standard No. 1325. The texture test resulted in 2.37 kgf of hardness and 71.96 N/mm of chewiness for the bologna that contained native starch from promising clone number 2, which showed a similar texture to the standard bologna. At a sensory level, the panelists noticed that the bolognas showed similar organoleptic characteristics, that is, native starch did not affect the flavor, color or smell of the standard bologna. Statistically, the results evaluated by a random ANOVA and multiple Tukey comparisons showed significant differences (p > 0.05) for moisture and pH content of the bolognas.

20

Authors: Carlos Felipe Urazán Bonells, Yeimi Johanna Pérez Hernández, Zulma Lorena Rey Sierra

For many years, mobility in big cities has faced ongoing issues represented in greater delays in travel times. These are more apparent when the route includes main and secondary roads, where intersections play an important role, particularly if a turn to the left is required. The projection of future main roads layout and corresponding intersections implies reviewing the impact that leftturn options, such as direct traffic light turn, turn after a u-turn, loop turn and turn going around the block, among others, would have on travel times. However, it becomes clear that there will be restrictions in some circumstances in which road infrastructure improvements are foreseen for already developed areas, mainly due to the fact that it is difficult to modify land occupied by buildings. Therefore, it is important to understand the impact that it generates in travel times. Out of 31 left turns, analyzed in 10 intersections, the conclusion is that the average time of a direct left turn with a traffic light is 23 seconds, whereas left turns going around the block increase to 219 seconds and left turns after a u-turn take up to 427 seconds. There is a considerable difference among the times, and these values can become critical when projected to a significant flow of vehicles.

22

Authors: Alejandro Mejía Sierra, Álvaro Antonio Patiño Forero

In order to showcase the impact of the technical development of micro and small entrepreneurs in Colombia regarding automation of their machines, the present article describes the landscape of the metal-mechanic industry development in Colombia, in contrast with the outstanding countries of the region, with aims to present the reasons that have driven countries like Mexico to be a production and manufacturing center for leading vehicle brands. This interest arises from the achieved competitiveness and, among others, the massive importation of numerical control machines, which makes Mexico the tenth country that imports the most machines. It is also important to highlight the relation that the Colombian manufacturing industry currently holds with the automobile industry. Finally, the article describes the process to design and build a numerical control machine required by a Colombian micro-entrepreneur dedicated to modeling pieces for the car sector.

23

Authors: Andrés Ríos, Edwin Rodríguez, Mauricio Ramírez, Jorge E. Pachón

Currently, the world’s vehicle transportation system is based on the internal combustion engine, characterized by its ineffective use of energy and constant emission of polluting gases into the atmosphere, decreasing the quality of air and affecting the population and the environment. However, private transport offers alternative technologies that have both economic and environmental advantages capable of entering the national transportation system. The present article assesses and analyzes these alternatives for the private transport system in Bogota, based on a linear model. This model compares the emission of polluting and greenhouse gasses, energy consumption, autonomy and associated costs of four different technologies (electric, hybrid, hydrogen and conventional fuel cars) in order to highlight the most critical aspects of each technology and define the best alternative for potential buyers and a future model of private transport in the capital city. Results show that there are alternatives capable of decreasing the environmental and health impacts associated to the use of conventional vehicles; said options also have the potential to mitigate the dependence on price and availability of oil at a cost that supports the feasibility of a future technology transition.

29

Authors: Adolfo Camilo Torres Prada, Fabián Augusto Lamus Báez, Sebastián Bahamón Blanco, Juan Sebastián Vesga Medina

One of the current issues in the mechanics of materials field is to perform an analytic determination of the stress state of non-deformable disc-type specimens subject to diametral compression. The present approach searches to contribute to the accurate design of new tests that allow a mechanic characterization of materials, tests required in sectors such as the concrete industry, rock mechanics and mechanics of other construction materials. One of the latest analytic proposals to solve the problem is found in the work of Markides, Kourkoulis and Chatzistergos, which shows an equation system with which to obtain the distribution of internal stress within a non-deformable disc. The present article illustrates the development of a calculation program built in Fortran programming language, with aims to study the change of stress states within the disc as the distribution of the compression varies in the perimeter of the sample, an area related to the internal angle ω0 measured from the center of the disc and reaches the limit of the contact area. Specifically, this experimental numerical stage seeks to establish the range of values of ω0 in which the stress of the disc presents primarily a compression state. The results show the distribution of radial σrr, tangential σθθ and shear τrθ stress for the geometrical case established in the present investigation. Moreover, it highlights that the state of the disc is controlled in particular by compression stress for a value of ω0 = 30º.