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This research identifies the technological competencies of Colombian public officials in the municipality of Riohacha to detect the digital divide that prevents the approach of these officials to citizens. With a qualitative-quantitative methodological approach based on a study case, a questionnaire is applied to 35 representatives of the mentioned municipality. The quantitative results are located at the low level, showing that they almost never use the potential of ICT to meet the needs of the population in terms of the services offered by the government, while the qualitative data responds to the socio demographic characteristics of sampling. Consequently, a government school is proposed in this paper for the training these officials in Information and Communication Technologies, so they can offer better service to the citizens. [ABSTRACT FROM AUTHOR]

This paper describes how multicore parallelism is implemented in the Haskell and Java programming languages, using two different programming paradigms, functional and object oriented. The starting point is an existing implementation of the sudokus solver algorithm, developed in Haskell with a functional approach, to which elements of basic parallelization were incorporated. After that, an equivalent version was constructed from object-oriented programming in the Java language. Finally, different measurements were taken to analyze and contrast the performance of the two implementations. According to the analysis, it was concluded that Haskell makes a more optimal use than Java of multicore architecture. [ABSTRACT FROM AUTHOR]

In this paper the particle swarm optimization (PSO) along with some of its variants is explored to give solution to the optimal reactive power dispatch problem (ORPD). This problem consists of the optimal use of reactive power resources in a power system, usually with the aim of minimizing power loses and improving voltage profile. The ORPD is a non-lineal and non-convex problem that involves continues and discrete variables and features multiple sub-optimal solutions. Besides the PSO technique, the variants known as Turbulent PSO (TPSO) and Turbulent Crazy (PSO) were implemented. Several tests were performed on IEEE 57 and 118 bus test systems comparing results with other reported in the technical literature. It was found that the performance of PSO is considerably improved when the variants TPSO and TCPSO are applied. [ABSTRACT FROM AUTHOR]

A model of multi-objective linear programming for reverse logistics sector of plastic polypropylene is presented in this paper. For this, a review of the theoretical framework related to the recovery process of polypropylene plastic from municipal solid waste and waste of industrial processes was done. Next, a multi-objective linear programming model which incorporates the variables and parameters identified in the design of the reverse logistics process was defined. Finally, a comparative analysis of a case study is done to determine the impact of the model on the results of the program logistics planning. An improvement of 12.6% was found in the costs associated with the program planning. At the same time, the Degradation to Processability Index is optimized which generates good quality recycled polypropylene. [ABSTRACT FROM AUTHOR]

This paper presents the development of two sensor networks as initial stage for the design of a prototype electronic tongue. One of these sensor networks was joined by commercial screen printed electrodes and the other sensor network was assembled from modified electrodes with pyrrole and different dopants. The capacity of discrimination and classification of different types of samples of commercial milk to two sensor networks was analyzed. The results show that the use of modified sensors with conductive polymers allows obtaining more complete information, classifying correctly samples of milk with different organoleptic and physico-chemical properties by the use of two main components that reproduced the 67,6% of information. On the contrary, the commercial sensor network evaluated on the same group of samples and equal conditions, obtaining 56,5% of the variability of information, showing in this way lower classifying capacity of the samples analyzed. [ABSTRACT FROM AUTHOR]

This paper presents a study done to find an interior point in the feasible region of linear programming problems is an aspect that should be solved in the initial stage of the implementation of the interior point algorithms used to optimize them. Consequently, it is proposed a methodology that starts with a formulation that does not require adding surplus or slack variables. It only includes an additional variable to generate a polyhedron in a new expanded space and with simple projections finds an interior point in the same polyhedron. It is demonstrated that the optimal solution of the extended linear programming problem allows obtaining a feasible point of the original problem or concluding that it has no feasible solutions. [ABSTRACT FROM AUTHOR]

In the Ecuadorian State there is no Social Education as a profession. Would it be necessary? Are there social or professional practices that fulfill their function, that being the case? The objective of this paper is to state initial questions that later allow understand the possible importance of this profession in Ecuador. This is an exploratory research which includes firstly a bibliographical revision about such broad issues. Secondly, it describes the brief experience of the profession in Ecuador, which establishes a link with Spanish Social Education. It makes a revision of Spanish Social Education development as a profession and it exposes its most basic characteristics. Finally, the document tries to clarify the situation of the profession in Latin America in order to raise questions that guide future lines of investigation. Perhaps, seek of Ecuadorian experiences regarding the issues related to Pedagogy and Social Education could contributes to start new actions to develop its own social professions. [ABSTRACT FROM AUTHOR]

The paper presents a model to analyse the production process of a large international milk-processing company, with the main objective of minimizing total production costs. Process optimization is an important task that must be solved during the strategic and operating steps of the company planning. The proposed methodology visualizes the situations as a linear blending optimisation problem and the model is based on goal programming methodology. The model was implemented using an original software application that is currently used in the company as an operational decision making tool. This system is a MS Excel add-in application written in VBA (Visual Basic for Applications). The experience of the users that are currently using the software is positive and the company shows interest to continue using the application. [ABSTRACT FROM AUTHOR]

This paper presents a comparison between different low-semantic descriptive algorithms coupled with a support vector machine and the deep learning algorithm, for the task of recognition and classification of aerial images. For this task, a database composed of 1200 images is used to fulfill the supervised trainings. The objective consists on classifying images in six categories that are commonly found on urban areas, in order to be used in any part of the world. The results show that with 150 samples of each class, the deep learning algorithm is capable of classifying images of avenues, buildings, industries, natural areas, residential areas and water bodies with an 87% of accuracy. Experimental results also prove that the labeled images as industry and buildings are the most complex ones to distinguish among these two classes, both for low-level descriptors and deep learning techniques. [ABSTRACT FROM AUTHOR]

This paper proposed a methodology based on an intelligent technique to analyze the failures in the different machines of a production line, in order to establish and identify the main variables that generate the greatest fraction of idle times in the system and to propose possible solutions. The development of the methodology was carried out in five steps. The first corresponds to the collection of information in a database; the second is the standardization of the description of the faults; the third is the application of data mining from the information collected; the fourth is the determination of the mathematical model to be applied; the fifth is to conclude from the results obtained. The tool used was WEKA (Waikato Environment for Knowledge Analysis) with the classification tree J48. The result of the proposed methodology in comparison with the current methodology, is positive, because it is achieved increase of 3.58 percentage points is achieved in the overall efficiency indicator. It is concluded that the tool is useful to identify and reduce idle times of a line of production. [ABSTRACT FROM AUTHOR]

This paper presents the study of the behavior of a stirred tank with hydrofoil impeller, used to mix water with polymetallic particles in the mining industry, through numerical simulation with CFD software. The mixture has an average density of 1.623 kg / m³ and an apparent viscosity of 0.065 kg / m-s, and was modeled as a non-newtonian homogeneous liquid. The homogeneous Euler-Euler model for free surface biphasic flow in steady state is solved in the simulation, using the k-ε turbulence model. The power curve, which correlates the power number (Np) with the Reynolds number (Re), was obtained from the torque curve of the impeller versus its angular velocity between 200 and 700 rpm. It was found that Np asymptotically converges to 0.32 in turbulent regime, a value that is in agreement with experimental results obtained in the present study and those available in the literature. [ABSTRACT FROM AUTHOR]

This paper presents an integration of the process of environmental licensing applied to Rio de Janeiro (Brazil) through the document Study and Report of Environmental Impact (EIA/RIMA). Also, the study analyzes the structuring of the recommendations of project management practices according to the Project Management Institute in the stages of initiation, planning, execution, control and closure. This is done to identify the efficiency in integration processes, stakeholders, scope, time, quality, cost and communication in the document project management plan EIA/RIMA. The contextualization of the national, state and local environmental licensing policies in Brazil was done. These are crucial in the making of the Environmental Impact Study. The integration of project management and environmental management documents contributes to form teams that are more committed with environmental responsibilities present in the work plans of environmental projects. [ABSTRACT FROM AUTHOR]

The objective of the study presented in this paper was evaluating the educational software Agroforestry World (Mundo Agroforestal) by rural young men and women from the educational institution Francisco de la Villota in Nariño, Colombia. Information and Communication Technologies are widely used for facilitating educational processes. The relatively new educational software Agroforestry World has not been assessed regarding the learning outcomes that might result from its application. Analyses were done through a TStudent test and a general linear model. After some time, significant learning processes in agroforestry were obtained. It was observed that the use of the software facilitated students' comprehension of the different topics, improving self-learning. [ABSTRACT FROM AUTHOR]

In this paper the reaction of enzymatic hydrolysis of the erythrocyte fraction of bovine blood was optimized through the response surface methodology. The effects of substrate concentration (S0: 8-12 %), enzyme/substrate ratio (E0/S0: 4-12 g/100 g protein) and pH (8-10), on degree of hydrolysis (DH) working to constant temperature of 55° C in a batch reactor, by 2 h were determined. The optimization of the statistical model obtained gave a maximum DH of 38.08 %, with pH 8.16; S0: 6.6 and E0/S0: 14.7, which was experimentally proved giving a DH of 36.25 ± 0.3 with negative bias of 5 %. At the optimal conditions samples were taken at three hydrolysis times to evaluate the antioxidant capacity, which was analyzed with ORAC, ABTS and FRAP methods. Greater antioxidant capacity was obtained at long hydrolysis time. After in vitro digestion it was confirmed that the antioxidant capacity of hydrolyzate remained. [ABSTRACT FROM AUTHOR]

Considering that there are electromagnetic, mechanical and thermal constraints that determine the design of high-speed electrical machines, the criteria that lead to adequate selection of the machine are established in this work. Moreover, taking into account the current state of technology, the critical values in the ratio (output power)/(rotation speed), are presented. The paper focuses on the high-speed synchronous generators, especially in permanent magnet generators, inductor alternators and flux switching alternators, emphasizing their constructive fundamentals and their advantages and disadvantages. The analysis is completed with a critical assessment that classifies them according to previously defined requirements. Although the decision of the final choice is largely determined by the application of interest, it can be said that, in general, synchronous generators with permanent magnets in the rotor are the best option. [ABSTRACT FROM AUTHOR]

This paper presents a study on the electrical performance of ceramic (ANSI 52-1, ANSI 55-2) and polymeric (ANSI DS-15) insulators used in medium voltage electrical systems (between 7kV y 35 kV) when fungi growth of Phanerochaete chrysosporium and Penicillium Sp. on their surface is presented. Biological contamination of electrical insulators is a problem that has been reported in tropical areas in Europe, Asia and Oceania and it may reduce the reliability of electric power systems. The biocontamination was conducted in Bogota, Colombia for 50 consecutive days (for each microorganism) using a chamber that controls light, moisture and temperature. Laboratory tests of flashover voltages and leakage currents were performed. After fungus biocontamination reductions in flashover voltages about 21% and 8% were reported for ceramic and polymeric insulators, respectively. In all cases, the leakage currents increased by 20% or higher. [ABSTRACT FROM AUTHOR]

In this paper the removal of total organic carbon (TOC) present in an effluent generated by the rendering industry was evaluated, by photocatalysis (photo-Fenton) and activated carbon adsorption. The effluent considered in the study was the condensed steam cooking that has high environmental burdens so conventional biological and chemical treatments are insufficient or are economically unviable. To evaluate the effect of process variables, concentration of Fe (II) and dose of oxidizing agent (H2O2), the response surface methodology was used. In the adsorption study, the effect of pH, adsorbent dose and contact time was considered. For photocatalytic treatment the TOC removal percentage obtained was 69.2%, while for the adsorption process was 77.9%. After that, the TOC removal of two coupled systems was evaluated. For one of the systems, the effluent was pretreated by adsorption and subsequently subjected to photocatalytic treatment, reaching an overall degradation of 91.9%. This synergy between adsorption and photo-Fenton processes appears as a viable option for the treatment of this type of industrial effluents. [ABSTRACT FROM AUTHOR]

This paper presents an iterative method for solving the power flow equations, starting from the establishment of non-linear functions on each node. With the proposed method, N-1 nonlinear functions are generated, which are iteratively solved to achieve convergence at voltages of each node in the power system. The convergence analysis showed that the two-step iterative method is fourth order. The original formula of Newton-Raphson method in the first step and Halley-type method in the second step is used in this work. Test systems with 14, 30 and 57 nodes are simulated to determine the characteristics of the proposed method. Among the strengths of the method it may be mentioned that it does not require sophisticated programming and that it represents an additional method for calculating power flows. [ABSTRACT FROM AUTHOR]

The aim of the study presented in this paper was to analyze the use of a mobile application, to facilitate the learning process of reading of illiterate adult population. The study fits in a more global concept promoted by UNESCO that recommends the provision of quality education for all people, using present technology. Additionally, the Mexican government is interested in reducing illiteracy and educational backwardness. The instrument used was a mobile application in Tablets operating under Android that was applied to 143 participants. The application was designed under an intuitive environment with audio instructions, selecting colors and images. The results found a high impact on teaching-learning, as the average time was reduced and users were highly satisfied. [ABSTRACT FROM AUTHOR]

The paper analyzes the kinds of management performed by Chilean listed companies located in geographical government spaces in Chile. The guide of the analysis done in this work considers the cultural factor of the region where Chilean companies are located affects the kind of management done by companies. The development of this hypothesis is made applying the accounting methodology of radar charts. The tensions existing between average period of maturation, which are represented on a radar chart, assumes that there exists a cultural factor on transactions made by companies in a region, and that the making-decision process on a management area has multidimensional effects. On this way, the decisions on general economy in a sector as well as the contrast of business activities respect to the mean values of a sector indicator are questionable. [ABSTRACT FROM AUTHOR]

This paper proposed the application of data mining to identify the psychosocial risk level in teaching elementary, middle y high school education in Colombia. A sample of 1100 data records corresponding to individual assessments were analyzed and processed. The samples were used as input data to the data mining tool called WEKA. Results were compared to assess the performance when applying data mining techniques and classification trees J48 and Naive Bayes. Finally, the application of this predictive tool allows the accuracy 91% compared to the clinic diagnostic. It is concluded that the method can be used tool for preventing the occurrence of psychosocial risk factors in Colombian public school teachers. [ABSTRACT FROM AUTHOR]

In this paper, the compressive strength, the resistance to carbonation and the chloride ion penetration of concrete mixes blended with high volume ground granulated blast furnace slag (GGBS) with water-to-binder ratios of 0.4 and 0.5 were determined. The study also investigated the effect of curing on the mentioned properties. Two methods of curing were evaluated: (1) air-dry curing, and (2) wet curing. The results showed that the dry curing conditions have an adverse effect on the properties studied, especially at high volume of GGBS. In contrast, wet-cured blended samples showed similar or even superior performance than the mixes using only the common Portland cement. [ABSTRACT FROM AUTHOR]

Se desarrolla y valida un metaheurístico para la conformación de lotes de acomodo del mínimo tiempo posible considerando k equipos de manejo de materiales homogéneos. El método debe servir también para la ubicación del depósito (depot, punto de inicio y finalización de la preparación de pedidos), y para determinar el tamaño de la lista de productos a acomodar, entre otros factores. La validación experimental fue realizada usando diseño estadístico de parcelas dividas. Como resultado de la experimentación se obtuvo que el metaheurístico denominado Búsqueda Inteligente en la Vecindad (INS) produjo ahorros de tiempo entre 24 y 50 min/lote respecto a la regla "el Primero que llega es el primero en ser servido (FCFS). Se muestra que el metaheurístico propuesto no solo contribuye al avance en el tema logístico sino también a la eficiencia operacional de la gestión de almacenes. This paper presents the development and validation of a metaheuristic for minimum time order batching in put away operations considering k material handling equipment. The method also serves to locate the depot and to determine the put away list size, among other factors. Experimental validation was performed by a statistical design named split plot. As a result of the experiment it was obtained that metaheuristic INS (Intelligent Neighborhood Search) generated time savings between 24 and 50 minutes per batch compared with the classical rule FCFS (First Come, First Served). It is demonstrated that the proposed metaheuristic not only contributes to logistic but also to the operational efficiency of warehouse management. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for measuring the export potential of business organizations. The literature related to orientation exporting was reviewed to identify the key factors in export competitiveness. With this information a measurement test was designed and validated. After this, metrics for the evaluation of export competitivity were defined. Following this, an application of the methodology in a business sector was done. The results show 16 key factors integrated in the financial, internal processes, customers, learning and growth, and markets. These results are validated by a content validity rate of 0.91 and a reliability coefficient Cronbach's alpha of 0.97. Based on the results of this work, it is concluded that the proposed methodology is capable of measuring export competitive conditions for enterprises which can identify and prioritize opportunities for improvement. [ABSTRACT FROM AUTHOR]

The aim of this paper is the presentation of the relationship between organizational culture and competencies for knowledge management of Small and Medium Size Enterprises (SMEs) in Colombia. The study initiates with the application of an evaluation model of knowledge management to 321 companies. For the study, analysis and synthesis methods were employed and a type of exploratory and correlational descriptive study was used. It is concluded that culture moderates positively and significantly competencies for knowledge management. This study is expected to contribute to the development of small and medium enterprises in the country to formulate actions to enhance their growth. [ABSTRACT FROM AUTHOR]

In this paper an innovative focus to programming Job Shop systems, based on sustainability, is presented. The following sustainability variables are evaluated: carbon dioxide emissions (environmental variable), sound intensity, accident rate and handled weight (social variables: occupational health) and finally, makespan time and direct labor costs (economic variables). The methodology is structured in fourteen steps that cover aspects such as multiobjective method design, description of genetic algorithms, and comparison with other methods. It is determined that the designed method shows greater performance for the variable weighted factor P(Xj) when they are compared with results from other methods such as programming rules and mobile bottle neck method. [ABSTRACT FROM AUTHOR]

This paper analyzes road connection of the city of Manizales (Caldas) with the municipality of Mariquita (Tolima) in Colombia. This route has steep topography, causing an inappropriate geometric design of the current road, such as minimum curvature radius and limited length between curves, making the trip uncomfortable for users. To solve the above problem were proposed four road alternatives, three made by the National Institute of Roads and one by a Public Private Partnership. None of them considered the geographic accessibility of the territories that belong to the area of influence. The methodology applied is an analysis of accessibility, which has as result the isochrones curves. After that, the economic and demographic variables are crossed obtaining as a result that the best alternative is that in which the road design includes more population and higher gross domestic product of the region, being then a solution that benefits to a higher number of people of the region studied. [ABSTRACT FROM AUTHOR]

This paper presents the results of a systematic mapping review about the recovery of architectural views from a software system, which was carried out using a methodological proposal found in the literature. Existing studies on the subject were identified, specifying the type of research, its purpose, the used recovery techniques, the aspects and architectural elements that is recovered, and the models used to represent the recovered architectural views, among others. It is concluded that it would be useful to have a unified and consistent mechanism for representing the results obtained by architectural recovery techniques, which facilitates their interpretation, analysis and reuse. [ABSTRACT FROM AUTHOR]

In this paper, the deterioration of a generator that suffered an overheating of 150 °C is presented. The thermal stress caused the separating of the conductive paint from the surface of the insulation, in some areas of the winding, because of the conductive paint did not meet the requirements of the Class F. This caused internal cavities under the conductive paint, which generated great magnitude sporadic pulses of partial discharges at low test voltage. This mechanism was monitored through the time. Partial discharges were eroding to the conductive paint, leaving ungrounded areas on the surface of the coils. Finally, partial discharges eroded to the insulation system, causing a failure to ground over a period of twelve years. The objective is to provide this experience to the present technical knowledge about deterioration mechanisms of high voltage generator insulation systems. [ABSTRACT FROM AUTHOR]

This article presents a comparison of the performance of the tools Hadoop y Giraph for the analysis and processing of large volumes of information or Big Data, with the aim of showing their usefulness for Big Graph processing. The analysis and processing of large volumes of information represents a real challenge nowadays. There already exist Big Data methodologies and free processing tools such as those mentioned above: Hadoop for processing large volumes of data, mainly non-related data, and recently Giraph for processing large graphs or Big Graph. In this comparison, this paper presents an analysis of the execution time cost for the practical implementation of the PageRank algorithm, which classifies Web pages according to their relevance, and of algorithms to find the minimum spanning tree in a graph. Experiments show that the use of Giraph for processing Big Graphs reduces the execution time by 25% with respect to the results obtained using Hadoop. [ABSTRACT FROM AUTHOR]

This paper presents the analysis of the environmental impact caused by the use of mortar whose binder is made with waste glass powder. Within the concept of sustainability, civil engineering should develop their ability to use building materials reusing waste products, whose final destination are controlled landfills and secondly to minimize the negative impact on the environment when they are put into work. To this end, tests have been conducted on specimen's filtration mortars containing waste glass powder as binder migration to identify potentially dangerous emission of harmful elements. The realization of these trials has resulted in that sodium is the only element liberated in detectable amounts (principally from the glass). All other elements are released in quantities lower than one mg/l, which represent no hazard to the environment. [ABSTRACT FROM AUTHOR]

This paper presents a technology surveillance process that takes into account activities associated with the process of conducting systematic literature reviews. Technology surveillance is a part of the research and innovation management system in industrial contexts. The aim of the proposal is to provide access, management and contextualization of scientific and technical knowledge to be at the forefront of technologies for supporting business strategy. Systematic literature reviews consider a detailed process to study the state of the art in a particular field of knowledge. This type of reviews constitutes a facilitator of effective technology surveillance processes. The innovative nature of the process is two-fold. On the one hand, integrates best practices to carry out technology forecasting and systematic literature reviews and on the other, a support tool (LOXO) is proposed for the execution of technology surveillance processes. [ABSTRACT FROM AUTHOR]

In this paper experimental results for a linear generator with different end-effect constraints to obtain a qualitative comparison for adjusting the linear generator geometry (windings length and stator length), are presented. The use of linear generators in energy harvesting systems is very common nowadays. One of the problems of this kind of electric generators is an induced voltage distorted due to end-effects. The end-effect is produced by the rotor speed change at the borders of the electric generator and impacts directly on the induced voltage waveform and in the energy flux to the load. However, is not included usually on the methodology design of linear generators. The proposal presented in this work allows obtaining a sinusoidal induced voltage waveform instead of a pulsing induce voltage waveform as has been reported in literature. [ABSTRACT FROM AUTHOR]

In this paper, the effect of the Motif Transform to design and develop texture-based descriptors for the Content Based Image Retrieval (CBIR) task is analyzed. The Motif transform assigns a number of limited range to local region of 2x2 or 3x3 pixels, to summarize texture feature and reduce the dimension of the descriptor. To analyze and evaluate the retrieval performance of the Motif-transform based descriptors, the performance of four descriptors based on the Motif Transform and four commonly used texture descriptors in the literature are compared. The performance of each descriptor is assessed by means of the Recall- Precision curve and the Average Normalized Modified Retrieval Rank (ANMRR) using four texture databases. The experimental results show that the descriptors based on Motif transform provide acceptable performance, keeping sufficiently small dimension, which is an indispensable requirement for any CBIR system. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of internal innovation projects with the aim of developing the innovation process of industrial products. To this end a methodology for improving the innovation model of a private company for innovation and technology services, named National Service of Industrial Learning (SENAI), located in Manaus, Amazonas (Brazil) is presented. To achieve this we conducted a literature review on the topic of innovation and to modify the innovation strategy a study with fifteen projects presented by SENAI in the year 2014 using the open innovation model was used. The analysis of the open innovation model and case studies allowed detecting the main problems, which allowed the creation of a new model with fifteen stages of innovation to work on innovation. It is concluded that the proposed model has allowed improving the management of innovation projects and that the model can be used by any company. [ABSTRACT FROM AUTHOR]

This paper presents a new temporal data envelopment analysis model that overcomes some weaknesses of the window analysis and Malmquist Index models reported in the literature. Time series are constructed with manufacturing data from the National Administrative Department of Statistics. For each series the best of a set of ARIMA models is selected, and a forecast for two periods is established. Changes in efficiency of the five largest industrial centers of Colombia are analyzed. For that, variables are located at different time positions including forecasts. The implementation of the new model shows the benefits of considering more than two periods. It also shows how classical Malmquist method is improved by changing deterministic univariate variables by time-series. Based on the results it is concluded that the method is close of being a data envelopment analysis in real time. [ABSTRACT FROM AUTHOR]

The development of a shorted annular ring (SAR) antenna with left hand circular polarization (LHCP), improving the axial ratio by means of slits and stubs is presented in this paper. The whole structure dimensions are 76mm x 76mm x 1.6mm, therefore it can be integrated into one side of a CubeSat 1U satellite. The proposed design shows an impedance bandwidth of 3.32 % from 2.37GHz to 2.45GHz frequency band, with reflection coefficient inferior to -10dB and maximum gain of 6.2dBi at a central frequency of 2.41 GHz. The results of the measurements, compared with simulation results are similar. However, a small difference in the measurements of the radiation diagram and of the reflection coefficient was observed. [ABSTRACT FROM AUTHOR]

This paper presents a model for analyzing knowledge management in the dairy productive chain in Colombia. Enabling elements, the process of creating and storing knowledge and competitiveness in 349 companies, were evaluated. This was done by using a measuring instrument with a Likert scale with scores from 1 to 5. The model shows that the concept of productive chain is more than a linking between the actors of the productive sector, the state and academia. To ensure effective management of knowledge it is necessary to be clear about the enabling elements and the functionality of the process of knowledge management as a strategy to enhance the competitiveness of the chain. The model contributes to generate deeper analysis in the area of knowledge management. It also supports decision making in the colombian dairy chain and can serve as a model for other sectors with similar conditions. [ABSTRACT FROM AUTHOR]

This work proposes a simple method named AbaniCO2 to unify the concept internationally used for estimating carbon footprint (CFP) a concept that does not have a universal accepted definition. The method organizes the different existing views in three major perspectives simplifying the understanding of the conceptual framework of the CFP and the analysis of the methodological complexities to consider in the process of adoption. First, the paper clarifies certain concepts that show the many factors that provoke the present situation of confusion and the lack of interest for adopting the CFP in the sustainable management of emissions of a company or a product, mainly in the Latin-American countries and in medium and small size enterprises. AbaniCO2 is the result of the systematization of previous works by the authors is in a simplified representation, in the form of a hand fan, of the different methodological streams that are nowadays available to quantify the CFP. The methodology consists of six clearly defined steps, starting with the definition of the objective behind the decision of adopting the CFP and ending with the algorithm of calculation to obtain a value for the CFP. It is concluded that AbaniCO2 simplifies the methodological complexities and reduces the existing barriers for the comprehension and managerial decision making about CFP adoption for the sustainable management in enterprises, organizations, and products. [ABSTRACT FROM AUTHOR]

The paper presents the development and implementation of an application for smartphones, which monitors and controls a real-time industrial process through an embedded system based on Raspberry, connected to the Internet using the Secure Shell protocol. The system integrates the advantages of virtual instrumentation with mobility for optimizing production processes and competitiveness in enterprises. The app was done using the mobile app development methodology, which consists of five stages: analysis, design, development, performing testing and delivery. Furthermore, the app was used in a pilot plant to verify its adequate operation and performance in a real environment, to evaluate its usability. It is concluded that the app has potential success for being implemented on a large scale, being easy to handle, attractive and efficient. [ABSTRACT FROM AUTHOR]

This paper presents the dielectric analysis of the stator insulation system of four 25 MW generators in a Geothermal Plant in Mexico. Since the first maintenance procedures white powder was detected on the stator windings, indicating that there were high partial discharges. Partial discharges erode the insulation system and eventually lead to failure. It was decided to investigate both the origins and the level of involvement of the insulation system to make maintenance actions. The evaluation was conducted in two stages. The first step consisted of on-line monitoring of partial discharges and the second step involved offline tests. The first step allowed establishing an initial classification of the machine with the least favorable dielectric conditions. In the second step, the mechanisms of deterioration of the windings were identified and corrective maintenance actions were applied. These actions provided reliability and availability of the four generators. [ABSTRACT FROM AUTHOR]

This paper proposes the control of an AC/DC boost converter with power factor correction using input and output power balance. The operation of the AC/DC converter is presented and the firing sequence of the converter is set is established. As a main contribution, the power balance is presented to obtain the amplitude of the input reference current that allows controlling the DC voltage output. Hysteresis band control for the input current is used, allowing the quick functioning of the control strategy. The proposed hysteresis band control works quickly and allows working in a wide operating range. Experimental results which validate the proposed control are presented. [ABSTRACT FROM AUTHOR]

This paper presents an optimal budget assignment model for improving quality service in distribution systems. The model consists on a multi objective problem which aims at minimizing maintenance costs in distribution systems while maximizing the reduction of faults rate. This last objective is measured through the SAIFI indicator (System Average Interruption Frequency Index). To solve the proposed model two algorithms were implemented: NSGAII (Non-Dominated Sorting Genetic Algorithm II) and a Memetic Algorithm. Several tests were performed with two real electrical systems of 100 and 200 nodes in the Department of Antioquia in Colombia, showing the applicability of the proposed approach. The optimal Pareto fronts obtained in the problem solution show a set of available options that represent a trade-off between both objectives and provides the system operator with an estimate of how much to invest in maintenance to achieve a desired value of the SAIFI indicator. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study aimed to obtain performance indicators in a public transport system, from three approaches, analytical, simulation and urban accessibility. For the study the Air transport Cable type of the city of Manizales in Colombia is taken as a case of study. The theoretical model of open networks of Jackson was applied, from the perspective of discrete simulation. The supply models are addressed through the analysis of urban accessibility, for which the data obtained by the Mobility Plan of the city, using the TransCad and Surfer software. The results show that for performance measures, a low rate of use of the transport system is obtained, which clearly confirms the results obtained by the analysis of urban accessibility. [ABSTRACT FROM AUTHOR]

This paper presents a procedure to formalize the information requirements to support the decision making process for a medium-size productive timber plant. The procedure is based on the principles of Constructivist Multicriteria Decision Aid Approach to capture, from those are involved with the process of maintenance, the lack of information, to organize and obtain the hierarchical structure, and from the principles of systems theory to define the functions and the information groups. As an additional result of this procedure the basis for an administrative system was obtained. This is obtained by defining the information network, the procedures to execute each function and the data structure for each group of information. [ABSTRACT FROM AUTHOR]

The present paper presents the design and application of a methodology that integrates three approaches, usually applied in an independent way, to enhance the quality of products by reducing their functional variability. The three methods are Quality Loss Function (QLF), Multivariate Statistical Process Control (MSPC) and Engineering Process Control (EPC). Improving product quality is achieved by the detection and control of the common and assignable causes of variation affecting the process. The methodology also allows integrating qualitative and quantitative perspectives for the selection of the critical-to-quality characteristics. By applying the methodology in a food company, a variability reduction of 52.49% was achieved. [ABSTRACT FROM AUTHOR]

The aim of this paper is to propose a methodology for selecting VoIP applications to be implemented in small and medium size enterprises. The methodology was applied to a representative SME such as a travel agency. To achieve this the following phases were developed: Identification of offered services, identification of providers in the geographic area, study VoIP application, study communication processes of SMEs and development of the matrix for the selection of applications and providers. The results of each phase provide data necessary for the implementation of the following step. To validate the usefulness and applicability of the proposed methodology, tests were conducted to analyze the quality of VoIP applications. Finally on the basis of the results obtained, it was found that the proposed methodology is useful to facilitate the selection of VoIP applications, according to the convenience of each SME and of their communication processes and economic conditions. [ABSTRACT FROM AUTHOR]

This paper presents a new heuristic called Snake and future possibilities for improving the indicators of blocking probability and data transport networks utilization. For this, the algorithms of Simulated Annealing, Genetic Algorithms, Tabu Search Algorithm and the proposed Snake are simulated in the WDM optical network NSFNET. The results show the new algorithm improves the blocking probability but not the display network utilization. The results show that there is a high consumption of network resources which negatively acts to meet future demand. This implies that changes are needed to improve the process and that it is also necessary to develop the algorithms that allow an improvement in both indicators. [ABSTRACT FROM AUTHOR]

This paper presents the aqueous synthesis of cadmium selenide quantum dots (CdSe QDs) with two types of capping agents: thioglycolic acid (TGA) and mercaptosuccinic acid (MSA). Optical band gap energy (Eg op), mean diameter of particle and growth curves of nanocrystals were obtained from the absorption spectra. The width associated with the size distribution of the nanoparticles (FWHM) was found using the photoluminescence spectra. Finally, photochemical water splitting was evaluated using suspended QDs in aqueous solution (50 mg on 0.1 L) and sodium sulfite (Na2SO3: 0.1 M) as sacrificial electron donor. The QDs capped with MSA showed H2 evolution limited by diffusion and a maximum rate of 1.126 µmol H2/h for QDs of 2.1 nm. On the other hand, QDs capped with TGA did not show hydrogen evolution. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of various nonlinear estimation techniques when is applied on a bioprocess. Extended Luenberger observer, Extended Kalman filter and Sliding Mode observer were evaluated for a microbial growth process. The performance of the nonlinear estimators is evaluated in terms of error indicators and their ability to cope with process uncertainties such as measurement errors and uncertain initial conditions. The simulation results suggest that the extended Kalman filter provide accurate estimates of the states and that the Extended Luenberger observer is not recommended for this type of bioprocesses. [ABSTRACT FROM AUTHOR]