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The effect of non-pharmacological interventions to contain the spread of SARS-CoV-2 have caused negative impacts, especially in education. Re-opening schools and universities is regarded as a high risk scenario. This paper seeks to understand, with the help of mathematical modeling, possible mechanisms through which the virus could spread in an academic environment and to quantify contagions attributable to participating in academic activities. To simulate the dynamics of contagion at the University, an agent-based mathematical model that incorporated stochastic differential equations was built using academic data for the University's 2020-2 semester. The model suggests that hybrid-attendance combined with epidemiological surveillance can produce very safe operating conditions without significantly contributing towards more COVID infections in the city of Bogotá. [ABSTRACT FROM AUTHOR]

For almost a year, humanity has been threatened by the new coronavirus known as SARS-CoV-2, which originated in China, and from there has spread to almost all regions around the globe. The incidence and mortality of this dangerous virus, which have recently increased in countries like Colombia, has overwhelmed public health systems and has created enormous difficulties and challenges at the economic, social, and political levels. With the aim of quickly finding treatment alternatives, running parallel to prevention initiatives spurred by the arrival of an effective vaccine, computational biology and computer-aided technologies have now been playing a booming role and have rapidly positioned themselves as key players in the pharmaceutical industry. This paper presents the main findings of a study focused on designing and discovering new agents with inhibitory capacity against the new coronavirus, describing the methodological strategy employed and presenting the implications, challenges, and future perspectives associated with finding a molecule with promising therapeutic potential. [ABSTRACT FROM AUTHOR]

This paper presents the results of four electromagnetic compatibility (EMC) tests carried out in the anechoic chamber of Universidad de los Andes (Bogotá, Colombia) on mechanical ventilators manufactured by different Colombian initiatives responding to the COVID-19 emergency. The four tests were carried out in accordance with the IEC 60601-1-2 product standard. The tests were the following: radiated immunity in the 80 MHz to 1000 MHz frequency, according to generic standard IEC 61000-4-3; radiated immunity at specific frequencies of 385 MHz, 450 MHz, 710 MHz, 745 MHz, 780 MHz, 810 MHz, 870 MHz and 930 MHz, in accordance with generic standard IEC 61000-4-3; conducted emissions, in accordance with the CISPR 11 standard; and radiated emissions, in accordance with the CISPR 11 standard. It describes the standards used to carry out the tests, the experimental setup used in each test, the observed results and the mitigation measures required to pass the tests. The results are discussed and necessary measures are suggested to promote the development of electromagnetic compatibility in Colombia. [ABSTRACT FROM AUTHOR]

Natech refers to a conjoint natural and technological hazard or accident. This paper is concerned with Natechs involving hazards arising from the handling, processing and/or storage of hazardous materials, as well as the transportation, of oil and gas by pipeline. Risk management of chemical accident hazards has generally been carried out using industrial risk management regulations and practices, engineering safety codes and standards, environmental regulations, and land use planning. However, there is evidence that existing regulations and practices may not be sufficient if the particular conditions associated with Natechs have not been factored in. Awareness of the need to better address Natech risk has been on the rise; nevertheless, this is not reflected sufficiently in the laws and regulations of individual countries, and a general framework for the governance of Natech risk is lacking. This paper provides an overview of Natechs, their characteristics, and the problems associated with Natech risk management. [ABSTRACT FROM AUTHOR]

The production of biogas is positioned as energy which can not only generate a source of renewable energy but also which recycles waste. In the context of sustainable development, the place of biogas is therefore essential. Several questions about safety issues, the harmonization of the regulations and the need to develop standards are discussed in this paper, based on the results of a workshop on biogas safety and regulation organized in November 2010 and the activities of the European Working Group on Biogas Safety and Regulation created after the workshop. The risks corresponding to the biogas production and use have been framed using iNTeg-Risk method and tools. Several deficits for risk management have been identified and a strategy to improve risk management proposed by the working group is presented at the end of the paper. [ABSTRACT FROM AUTHOR]

This paper presents UnaGrid/UnaCloud: an opportunistic computing infrastructure solution, which provides fundamental computing resources (processing, storage and networking) on demand and at lower cost, to support academic and e-Science projects. The proposed computing infrastructure is provided through the opportunistic use of idle computing resources available in a university campus. This paper describes the architectures defined, implementations deployed and test cases. The results obtained evidence high efficiency in result generation, improving limitations of projects depending on the agile provision of large computational capabilities, including scientific and academic initiatives. [ABSTRACT FROM AUTHOR]

This paper presents the design and implementation of an isolated microgrid developed in La Guajira, north of Colombia. It was designed through the collaboration and capacity building of the community itself. Several activities were developed by the research group in order to improve the technical design. With the objective of reaching a consensus in terms of the final desgin, several visits were made to the community. During the implementation, some new ideas on how to improve the design appeared. In any case, if the microgrid (that uses both solar and wind energy) would be replicated in any other location, we strongly recommend to include, from the beginning, the community needs and the ideas of its inhabitants. [ABSTRACT FROM AUTHOR]

Housing policy in Latin America cannot be regarded as having been a huge success. Official figures show that the housing deficit is rising in most countries. Of course, solving the housing problem is difficult and complicated further by rapid urban growth and too much poverty. Nonetheless, there are many failings in current housing policy and the current paper identifies ten myths that have infiltrated the housing policy lexicon. This paper is an invitation to the region's governments to consider whether any or all of the identified myths persist within their own policies and whether those myths are as damaging as will be suggested here. [ABSTRACT FROM AUTHOR]

This paper studies a series of practices and experiences taken from massive regional infrastructure projects sponsored by the IDB (Inter-American Development Bank). In an effort to contextualize the idea of a megaproject, it describes what one is, demonstrates its importance to the community where one is built, and investigates the relationship between the community and the megaproject itself. In addition, the paper takes a deep look at regional experiences, the training required to execute large projects, and other associated needs. Furthermore, insight is given on key elements of project preparation, types of organic changes that take place in project execution, and how these changes can be anticipated. Lastly, a few brief case studies of regional experiences are given to emphasize various lessons learned. [ABSTRACT FROM AUTHOR]

The Electrified Mass Rapid Transit Systems (EMRTS) are one of the possible alternatives in solving mobility problems in urban and interurban areas. In this paper, we present the theory which allows modeling and determination of the EMRTS electric load, which serves as a base for the development of a computing model. The paper presents two examples of application: a tramway line and a subway line, from which we can observe the energy supply requirements of these EMRTS to the electric distribution system. [ABSTRACT FROM AUTHOR]

UML, SysML, and WebML are graphical modeling languages (GML). Despite their similarities, these languages cannot be jointly interpreted, since they exhibit different kinds of models and diagrams. Some studies for examining the features of some GML are proposed in the state of the art, but applied to individual languages, avoiding the common features among such languages. In this paper, we propose an ontology design and implementation for summarizing GML concepts and relations. We use a methodology created in the Stanford University. The developed ontology can successfully answer 35 competence questions, some of them exemplified in this paper. [ABSTRACT FROM AUTHOR]

This paper describes the development of a computer application for production planning and scheduling in a Colombian auto part company. Such an application integrates sales forecasts and firm orders, to calculate a Master Production Schedule which is validated with a detailed shop floor scheduling plan. A case study illustrates the functionality of the proposed application and compares the computer-calculated production plans with the current practices. The results show that the implementation of the application can improve service levels and customer satisfaction, given some prerequisites described in the paper are met. [ABSTRACT FROM AUTHOR]

In the dynamic systems a fail can occur in any moment, the fail can be present for variations in one or more parameter of the dynamic system. This paper present a fail detection in a non linear system compose by two tanks in parallel one with constant transversal area and the other one with variable area, the work is develop with adaptive observers and LAMDA classification. The application on this paper is in a non linear system, the level control in the two tank system. [ABSTRACT FROM AUTHOR]

This paper shows the evaluation and design of traditional traverse flute through experimental and computational engineering analysis. This work required the study of the dynamic and acoustic parameters that govern the behavior of this type of instrument. A flute, as a musical instrument, must have certain sonorous and anatomical qualities for a pleasant performance by the player, as well as to the listener. The study of vortex generation caused by air entrainment in the tube is found to be of great importance, as it is shown in this paper. Basic engineering design criteria are presented for the improvement and construction of wind musical instruments, such as pipe-organs, quenas, ocarinas, to quote just a few. [ABSTRACT FROM AUTHOR]

One of the major construction systems in Colombia, and in general throughout Latin America, consists of multistory moment resisting reinforced concrete (RC) frames filled with unreinforced masonry (URM) walls. These non-structural masonry walls are conventionally built using clay tiles. Due to the high seismic activity in Colombia, this kind of masonry wall is prone to damage. One of the alternatives being explored in Colombia to prevent the failure or lessen the damages in clay tile URM walls is to strengthen them with Glass Fiber Reinforced Polymer (GFRP) laminates. This paper presents promising results of experimental tests conducted on twenty-six wallettes of 9x70x70 cm and 9x120x120 cm, which were strengthened with different layouts of GFRP laminates. In addition, a full-scale wall was tested to validate the technology. The paper discusses the effect of GFRP laminates on the failure mechanisms, capacity and ductility parameters as well as on the overall reduction of earthquake damage for clay tile URM walls. [ABSTRACT FROM AUTHOR]

Performance evaluation of communications systems is usually done by analytical techniques or simulation. The analytical approach is normally based on a probabilistic description of the system operations in terms of Markovian processes or queuing systems, but only is directly applicable for simple systems, or simplistic models of complex systems. Simulation is a powerful tool but requires enormous computations to yield accurate performance estimators. In this paper we present an alternative technique: Petri Nets, a graphical and mathematical modeling tool applicable to many systems. We used Stochastic Petri Nets to model and evaluate queuing systems and some protocols. Simple and accurate models were developed. The main definitions relating Petri nets in general, and to the particular classes of Petri nets are summarized in Section 1. The following sections contains queuing models (Section 2), Stop and Wait and Aloha protocols (Section 3), DSP protocol (Section 4). Section 5 concludes the paper. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study that evaluates the incorporation of FACTS technologies in the expansion planning process of the Colombian National Transmission System (NTS). The application methodology uses as starting point the optimization of the exploitation of the existing system by increasing its transmission capacity and it is based on steady-state analysis. This paper presents the results of the feasibility study for a wide application of FACTS systems in the Colombian Transmission System for improving transmission capabilities and reliability and security levels after year 2005. [ABSTRACT FROM AUTHOR]

This paper describes some approaches for the water balance modeling of fluvial and coastal wetland systems, where one or more water bodies are interconnected, interacting with a river and/or the sea. The modeling methodology is based on the continuity equation and the hydraulic behavior of the connection channels. In this paper, the models for four wetland systems located in the Lower Magdalena River floodplain are presented. Typical results are included to illustrate the type of information these models can give to contribute to the knowledge of the dynamics of these fragile ecosystems, their recuperation, preservation, exploitation and sustainable management. [ABSTRACT FROM AUTHOR]

The execution of the programs directed to the improvement of the tertiary road network depends to a large extent on four entities: the ANI, the INVIAS and the Ministries of Transportation and Postconflict. In this article, which is an adaptation of his paper in the Forum Tertiary Paths for Peace, Luis Fernando Andrade, President of the ANI, says that innovation is necessary in paving methods, in the efficient use of materials that once Have been ignored and the role that academia has in this goal. And, on the other hand, the importance of linking communities in the construction and maintenance of the roads they use daily for the development of their family economies and access to basic services. [ABSTRACT FROM AUTHOR]

The National Federation of Coffee Growers (FNC) is the largest coffee growing organization in the country, and it assembles coffee growers from departments including Caldas, Antioquia, Quindío, and Risaralda. It has spent the past ninety years ensuring improvement in the quality of life for the people living in these areas. One of the FNC's many undertakings that should be emphasized is the construction of road infrastructure that allows for coffee to transported and therefore sold and the social development of the communities in its areas of influence. This paper is written by Mauricio Medina, the leader of the FNC's Social Development Unit, who emphasizes that if the projects are to be successful, it is necessary to turn to these types of experiences for post-conflict investments. [ABSTRACT FROM AUTHOR]

The long-standing conflict in Colombia has inflicted substantial costs on the population and the economic development of the country. Since conflict occurs mainly in the country's rural areas, the economic impacts of violence are higher for these territories. The purpose of this paper is to describe the impact of armed conflict on Colombia's rural population and the current conditions of rural areas as well as discuss whether the peace agreements with FARC may contribute to improve these conditions. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the role of engineering and research in the environmental licensing process in the light of institutional changes made in Chile since 2010: the creation of the Ministry of Environment and the Environmental Assessment Service. To do this, we will show the challenges posed by these new institutions, the opportunities identified and the work undertaken to address those changes. Finally, the results will be presented taking the Punta Alcalde project as a model. [ABSTRACT FROM AUTHOR]

Satisfaction is a dimension of usability for which quantitative metrics cannot be calculated during user interactions. Measurement is subjective and depends on the ability to interpret questionnaires and on the memory of the user. This paper represents an attempt to develop an automatic quantitative metric of satisfaction, developed using a Brain Computer Interface to monitor the mental states (Attention/Meditation) of users. Based on these results, we are able to establish a correlation between the state of Attention and the users' level of satisfaction. [ABSTRACT FROM AUTHOR]

Advanced gas leak detection methods in industrial environments are of vital importance as they may translate into a reduction of accidents and increased economic efficiency. This paper proposes the use of different sensors for detecting and localizing leakages remotely, based on the measurement of variables involved when a leak is present. The processing and fusing of thermal, depth and visual images, as well as gas concentration scanning technique, is the proposed method in this article. [ABSTRACT FROM AUTHOR]

Colombian amazon has a wide biologic diversity, with silvester and cultured species which use potential and abundance identified them as an important bioactive compounds source. That represents a wide opportunity to innovate and develop processes and technologies in different engineering fields (chemical, mechanical and food engineering). This paper presents experiences when the problem of sustainable use of biodiversity is tackled from engineering in the Colombian amazonic region. [ABSTRACT FROM AUTHOR]

The aim of this paper is to generate photogrammetrie products and to automatically map buildings in the area of interest in vector format. The research was conducted Bogotá using high resolution digital vertical aerial photographs and point clouds obtained using LIDAR technology. Image segmentation was also used, alongside radiometric and geometric digital processes. The process took into account aspects including building height, segmentation algorithms, and spectral band combination. The results had an effectiveness of 97.2% validated through ground-truthing. [ABSTRACT FROM AUTHOR]

This paper will address the components of the International Code Council (ICC) as one of the most important organizations in terms of developing the model building codes for the US: the international codes. This membership-driven organization has the task of providing the building industry and all its stakeholders with the necessary regulatory documents, training, certification, plan check, product evaluation, and accreditation services to achieve safer and more sustainable building construction. This article provides an overview of the building codes in the U.S., the ICC and its subsidiaries, and ICC's systems designed to support the codes and the regulatory industry. [ABSTRACT FROM AUTHOR]

The last stage of classical transport modelling, known as the sequential model of the four steps, estimates the flow pattern of the system. Then, in a post-processing phase all measures of system performance such as the level of service and externalities are estimated. This paper compares the estimated BPR and conical volume-delay with data taken in six multilane roads in Bogota, finding ranges of recommended function parameters values. We concluded that the values traditionally used for these functions are not the best for explaining the congestion that occurs in the environment studied. [ABSTRACT FROM AUTHOR]

This paper presents a literature review analyzing four topics concerning wind systems for micro-generation: system topologies, system modeling, power converters design, and power converter controllers. The review also reveals the open research problems in the literature, and the opportunities to improve commonly adopted solutions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to apply the MUSA method to the information gathered in periodic surveys monitoring student satisfaction (ESAT, for its acronym in Spanish). The surveys serve to diagnose the level of undergraduate students' current satisfaction at Universidad de los Andes (Colombia), and to identify the importance and the current performance of each of the aspects assessed by the institution. In addition, it sheds light on the elements that students consider most valuable as part of their satisfaction, taking the results issued by a significant sample of respondents. Finally, the study presents aspects that require the University's attention in order to improve student satisfaction. [ABSTRACT FROM AUTHOR]

In this paper, we present a forecast of Colombia's hydrocarbons reserves and production for the 2013 to 2015 period. These results are the product of an adjustment conducted by Unidad de Planeación Minero Energética (UPME) of the scenarios generated by Arthur D'Little. This study is based on a methodology of scenario analysis which considers the impact of internal and external factors according to different uncertainty levels and their incidence on the future development of the sector. For these scenarios, the corresponding required investments for their realization are calculated. The analysis results make evident the importance of Colombia's potential in hydrocarbons. The incorporation of more than 9 billion barrels of oil and 6 tera-cubic feet of natural gas has been forecast. These achievements will depend on the investments in exploration and the development of oil prices as well as on a more efficient management of the associated environmental and social issues. [ABSTRACT FROM AUTHOR]

Residential water networks (RWN) are the last segment of a water distribution system. These networks must supply the users with the correct amount and quality of water at any point in time. To achieve this, the correct design of RWN's implies a sound understanding of the future water demands and the way in which it will present itself. This paper proposes a methodology for calculating the parameters that define the water demand pulses and the calibration realized for a case study. [ABSTRACT FROM AUTHOR]