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This article presents the results of the carried out experimental investigation on the hydrotransport of mixtures in open channels. The author investigated non settling mixtures composed of pulp of paper and water in an open channel of circular cross section. The object of the investigation was to determine the energy losses due to the flow of water and pulp of paper and to propose a methodology for the design of open channels for mixtures. For the experimental development an assembly of laboratory was built in which a circular channel with variable slope was adapted. As a result it was possible to obtain new equations for the coefficient of friction of Darcy-Weisbach and the coefficient of friction of Manning, which relate these coefficients with the properties of the water, those of the mixture and the slope of the channel. With the equations obtained in the investigation the author it proposed a new methodology for the design of channels that they transport mixtures of water and paper pulp. [ABSTRACT FROM AUTHOR]

To improve diesel engine conditions, parameters such as fuel load conditions (low, high and partial), which influence the stability and speed of combustion, and the generation of emissions, should be analysed; in addition to the ideal blend of biodiesel and injection time. The effect of the injection when applying biodiesel, can generate increased consumption, with its higher viscosity causes a greater injection delay, alternatives are recommended to solve this and other mishaps. In the case of the compression ratio in the diesel engine is another factor that influences the reduction of emissions when applying biodiesel, as well as engine performance. In this paper we study the result of the dual function when applying biodiesel as pilot fuel and biogas as main fuel; with the latter, the use of bio-diesel can be made more competitive, positioning it as a main fuel or as a pilot fuel for the engine. Finally, the phenomenon of the hit and the emissions generated from biodiesel in the diesel engine are analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the design of a tuned mass damper (TMD) for vibration control of a simply supported metal beam. Considering the mechanical properties of commercial springs and magnetic dampers, and applying the finite element method, the feasibility of couple a TMD that allow to reduce vibrations in the beam was evaluated. This paper describes the beam mechanical properties, as well as the characteristics of the tuned mass damper. These results can be used in construction of dynamic models that promote the experimental study of structures. The equations proposed by Deng Hartog were used to identify adequate stiffness and damping. Finally, it was evaluated the performance of the TMD in vibration control under impact excitation conditions. With the implementation of this device, were obtained reductions of more than 90%. [ABSTRACT FROM AUTHOR]

We calculate emissions of criteria pollutants (VOC's, PM10, CO, NOx and SOx) from point sources for the year 1997 in Cali-Yumbo (Colombia). Data were obtained from 108 emission declarations to environmental authorities. We applied the method of emission factors for most of the sources which had no direct measurements and reported type and amount of fuel used. We find that paper manufacturing and printing/publishing industries generate the most pollutants overall, followed by non-metallic minerals and textile/apparel industries. While the sources in the city of Cali were responsible for most of the volatile organic compounds (VOC's), emissions of sulfur oxides and particulate matter originate mostly from sources in the industrial town of Yumbo. [ABSTRACT FROM AUTHOR]

The main goal of ontologies in computing is related to the definition of a common vocabulary for describing basic concepts and relationships on a specific domain. Main components of ontologies are classes -- concepts--, instances, properties, relations, and axioms, among other elements. The ontology population process is intended to receive an ontology as input in order to extract and relate the instances of each ontology class from heterogenous information sources. In this paper we perform a systematic state-of-the-art review about ontology population. We select papers from specialized databases and we create a research question for driving paper search. The results of our review points out ontology population as an interesting topic for researchers. Even though we have several techniques for driving the process, fully automated tools are still missing and we also miss high levels of precision and recall. [ABSTRACT FROM AUTHOR]

This paper aims to expose the state of the art about the Last Planner System (LPS), production planning and control system that has transformed construction industry at operational and management level. After doing a systematic literature research in international databases, 116 papers from different countries were selected, whose content focuses on the theoretical framework of the methodology, case studies, support tools, integration with other methodologies and implementation in design. [ABSTRACT FROM AUTHOR]

This paper considers the problem of determining the best inventory management policy for perishable products on fish trading companies. The main objective is to determine the inventory management policy with safety stock for a probabilistic model, which maximizes the expected daily profit by considering the product, by considering that the products are perishables and only could be stored for a maximum number of days. This paper proposes a methodology based on Montecarlo simulation. Computational experiments using real world data from a fish trading company in the Colombian market shows the efficiency and the effectiveness of the proposed methodology based on the maximization of the average net profit. [ABSTRACT FROM AUTHOR]

Basic wind velocity for civil engineering purpose is determinant for structural design under wind action. Basic wind velocity is obtained from data measurements at meteorological stations supposedly placed in ideal terrain conditions, and it is estimated by different statistical methods. Not all stations accomplish the ideal conditions, therefore, correction of the wind velocity values must be done. The main objective of this paper is to define a roughness correction factor for wind velocity in not ideal conditions, and to compare basic wind velocity obtained with proposed basic wind velocity for the Cuban territory at international studies. Two meteorological stations with different terrain roughness were selected, and the basic wind velocity for each one was obtained by applying the Method of Independent storms (MIS). Roughness was found through the Method of Classifications and the Morphometric Method, with the use of satellite LandSat8 images. Results show that modified basic wind velocities are similar for the two methods. The comparison with international studies proved a good correspondence only with one of the stations, hence it is recommended to extend the study to a greater number of stations. [ABSTRACT FROM AUTHOR]

This paper presents the development of a gamification-based mobile app to support the implementation of an ISO 55000 asset management system in Codensa. The Energy Assets mobile app, proposed as a strategy to introduce the concepts of the ISO 55000 asset management systems and the CREG 015 resolution, which gives the mandate for the implementation of the standard, is shown. The methodology, from which the eight (8) levels of the game were designed, is presented, and the basic concepts of asset management systems, the life cycle of an asset, and the general provisions of CREG resolution 015 are discussed. For the development of the different questions included in each level, multiple strategies were applied, such as single selection, multiple selection, association of concepts, and completing definitions. Finally, gamification as a digital strategy to support Codensa's ISO 55000 certification objective, and in general to involve its collaborators in projects of general interest, is highlighted. [ABSTRACT FROM AUTHOR]

This document presents the development of a cybersecurity platform for unmanned aerial vehicles (UAV), or drones, based on cyber-deception technology. This technology is based on the deliberate creation of easily accessible and detectable decoys (or honeypots) to detect potential intruders at the perimeter of a critical infrastructure. This document contains an explanation of the conceptual model of the proposed solution, and a detailed description of each of the developed procedures. A technological development methodology was implemented in this paper. Also, procedures were developed for the creation of honeypots in Wi-Fi wireless networks and in radio frequency bands, and the approach to the development of a GPS spoofing procedure was included. The latter was explored using software defined radio equipment (SDR) for the impersonation of GPS signals, which allows for the implementation of defense strategies against attacking drones. Finally, a web platform to monitor active decoys, and to register penetration attempts, is described. These penetration attempt records are stored in a blockchain, developed with basis on Ethereum technology. It was found that Wi-Fi and radio frequency wireless networks have vulnerabilities that can be exploited by potential attackers. Also, that the GPS spoofing procedure is much more complex than procedures by wireless networks, but it would allow to take action on attacking drones. [ABSTRACT FROM AUTHOR]

This paper presents an application of the AHP methodology to select a waste electrical and electronic equipment (WEEE) to be considered in the design of a reverse logistics chain for the integrated management of the solid waste that those appliances generate. This work is the first step for the design of the logistics chain and has been addressed through the multicriteria viewpoint due to the importance of the WEEE environmental and economic impacts. The paper includes a broad and detailed characterization of the electrical and electronic equipment with the greatest presence in Colombian homes. The exposed methodology can be easily replicated for any other type of equipment or solid waste in the configuration process of the reverse supply chain. For the specific case presented here, cathodic ray and LCD TVs have been selected. [ABSTRACT FROM AUTHOR]

Wood is considered a versatile and valuable material. It is used as an energy source or as a structural material -for its mechanical properties and visual appearance- and also for the production of non-food consumer products, such as pharmaceutical products, adhesives, textile products, polymeric compounds, cosmetics, papers and various basic products. Motivated by the diversity of wood species and the increasing availability of wood residues, the following investigation is intended to characterize the residues of three timber species that predominate in Colombian industry: Tectona grandis, Pinus patula and Acacia mangium, in order to promote their transformation into industrial products of greater value than the waste product. Sample wood was subjected to physical, chemical and thermal characterization by means of tests of: density, pH, last analysis, proximal analysis, lignocellulosic content, extractive and calorific value. The results obtained allowed the evaluation of wood waste as a resource of greater value to generate recycled products such as particle boards, fibers or laminated and other materials such as biopulps, composite materials, bioadsorbents and activated carbon, and also the production of fuels type biochar, syngas and bio-oil. [ABSTRACT FROM AUTHOR]

Software Defined Radio (SDR) is a technology with recognition in Telecommunication industry because of its capacity of developing reconfigurable communication systems. This paper presents the implementation and field-testing evaluation for a low-cost radar system using the gr-radar toolbox created into the version 3.7.4 of GNU Radio. Tests allowed to measure distances and velocities of a target in movement. Velocity estimation errors were obtained with 1.8% and 3.22% in a round trip. Range estimation errors were also obtained with 1.56% and 2.75% in a round trip. Radar system was configured to transmit at 2.4 GHz with Multiple CW technique. The test scenario was the Nueva Granada Military University Campus in Colombia. The results are oriented toward using this tools for deepening on basic Radar principles with low-cost devices. [ABSTRACT FROM AUTHOR]

Telecommunication towers and other structures composed of steel sections are particularly susceptible to the action of wind loads that need to be quantified for a correct design of these sections. In the obtaining of wind loads, the determination of the drag (CD) and lift (CL) coefficients of the elements that compose the lattice, is vitally important because, from these coefficients, the separation and the permeability of the lattice is estimated the acting wind load. This paper studies the influence of the blockage ratio on the CD and CL coefficients in an equal-leg angle section, widely used in this kind of structure. To obtain these coefficients, computational fluid dynamics (CFD) was used through OpenFOAM software. As part of the experiment, three blockage ratios were simulated: 5, 10 and 20%, using as a comparison pattern the CD and CL values provided by the NBR 6123 1988, NC 285 2003, NBCC 2005 and ASCE 7-10 2010 standards [1]-[4]. The best results were obtained for a 5% blockage. [ABSTRACT FROM AUTHOR]

In this paper results from a research in micromachining of biocompatible polymers are presented. The paper describes the fabrication process for biocompatible polymers components and shows the accuracy levels and the dimensional scales that can be achieved with a Kern Evo micromachining center. Furthermore the paper also shows the results obtained from a microcutting test using carbide end mills of 100 microns diameter on medical-grade PMMA (Polymethyl methacrylate) specimens to determine the parameters that minimize the burrs size. To characterize the final surfaces state and the condition of the tools, optical and electronic microscopy techniques were used. The results for the first machining tests show that to control the dimensional characteristics of the component, aspects like the setting depth of cut, the selected fastening method and the alignment tolerance must be watched over; even the environmental conditions of the place where the machining center operates must be also controlled. [ABSTRACT FROM AUTHOR]

This paper presents a literature review about alternatives for determination of requirements in software development projects. The literature searching begins from a fundamental principle, request information about methods of determination of requirements that do not need a high percentage of interaction with users or customers. This usually happens because users or customers don't have time as it happens when traditional methods are used. The search for information was made taking into account the low interaction with the user or customer and in this vein, it was needed to expand the search horizon until 2000 and it includes classic texts in the study area. The search results provided insights about the techniques of requirements engineering, whose main characteristic is to minimize the interaction with users, such as, prototyping, document analysis and legacy software which are the closest ones to the search condition. [ABSTRACT FROM AUTHOR]

The objective of this paper was to compare the incidence of dynamic difficulty adjustment (DDA) in a in a motor skill rehabilitation game, compared to a manual configuration. To achieve that, a virtual tool called "Bug catcher" was developed, which is focused in upper limb rehabilitation. This tool uses a DDA based in fuzzy logic. The population involved for the present study were made by two users, an 18-year-old patient with a hemiparesis that limits her motor ability in her left upper limb, and a 37-year-old patient with motor monoparesis in his right upper limb. This tool was used in both users, each one with a different configuration (automatic or manual), and the motor ability from both participants was objectively measured using Box and Blocks Test, applied before, during and after each session; additionally, a performance index (percentage of success) was defined in order to determine the progress of the participants in the virtual tool. As a result, it was obtained that user number one using the game with DDA, managed to obtain not only a better performance in the sessions but also an important advance in her motor skill in comparison to the user 2 with the manual configuration. [ABSTRACT FROM AUTHOR]

The passing sight distance (DVA) required for a stretch of road is obtained from the geometric design manuals of roads and road signs of each country; in Colombia there are the road geometric design Manual of the 2008 [1] and The 2015 [2] road signs Manual to get it. The objective of this paper is to apply and compare the methodologies established in each one of them to calculate the required DVA and to measure the DVA available in planes. When comparing these last two are indicated the sections where it is permissible to advance to signal the axis of the road with discontinuous line. When calculating the required DVA in each one of the Colombian's manuals, different values are obtained. To understand the effect of these and the differences on road signs, the values and methodology of each of them are applied to the Tunel de Occidente Road-San Jerónimo, which is a two-lane representative road and located in Antioquia department, Colombia. After having the respective road sign, gaps and contradictions were detected In the Colombian regulation of road design and signposting. [ABSTRACT FROM AUTHOR]

The tourist destination Cayo Santamaría in the province of Villa Clara, Cuba, has a constructive accelerated development. Currently does not have interconnection with the national electrical system that ensures the autonomy of the electrical system, and there is a great difference in the electric power circulating through of the distribution circuits that feed the loads. An analysis that would deliver these loads evenly for connection to the distribution channels became necessary. Therefore, it is necessary an analysis that allows to distributing these loads in a uniform way for their connection to the distribution circuits. This paper realize a study on the possible connection variants of the load groups of hotel centres to the distribution circuits, concluding which optimal variant to perform. It was analyzed system response from faults in the circuits, proposing solutions to extend the post-failure stability. The results obtained are a starting point for an optimal operation and more reliable of Cayo Santa María isolated system. [ABSTRACT FROM AUTHOR]

In this paper, a study about the mechanical behavior of mortar modified with sawdust fibers under compression load was performed. Density, compressive strength and dynamic elastic modulus of mortar modified with 0%, 0,5%, 1% and 3% of sawdust were estimated. Composites were evaluated after seven, 30 and 90 days of curing. In addition, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to chracterize the morphology and to find elemental composition for both, fibers and cement matrix. The results show that compressive strentgth, elastic modulus and density decreases as sawdust percentage increases. It is suggested to use 1% of sawdust fiber mortars in order to avoid an important reduction of the mortar mechanical properties. [ABSTRACT FROM AUTHOR]

Fatigue cracking is one of the most common damage mechanisms on the pavement structures. This phenomenon is associated to the damage produced by repetitive load application, whose load magnitude is lower than the maximum admissible resistance that the material may resist. Because of this, the continuous application of loads generated by the traffic creates a progressive damage in the pavement layers. Currently, there are different methodologies that allow predicting the fatigue cracking, but most of these methodologies are complex procedures which may not guarantee the failure of some types of mixtures and may not relate the applied load conditions to those suffered in the pavement. For this reason, to understand the fatigue cracking behavior of asphalt mixtures is essential to develop effective fatigue tests. In this context, the main goal of this paper is to propose a test methodology to evaluate fatigue cracking by using a notched cylindrical asphalt concrete specimen. The proposed method allows reproducing the pavement tensional state, avoiding the stress dissipation, and focusing the strains in the middle of the previously groove carved specimen. A semi-dense asphalt mixture gradation, used in asphalt pavement surface layer, was chosen. Three types of aggregates were evaluated, determining their fatigue laws. Besides, an analysis of durability of asphalt mixtures was presented. [ABSTRACT FROM AUTHOR]

This paper presents a novel methodology to solve the problem of Optimal Reactive Power Flow (ORPF) in interconnected multi-area power systems. The main contribution of this paper is the use of a coordinated-decentralized strategy that allows keeping autonomy and confidentiality in the operating processes of each area. In the proposed model of multi-area ORPF the Transmission System Operators (TSOs) of each area operate independently, and do not need explicit information regarding neighbor areas, being only necessary to exchange border information related to the interconnection lines between areas. The proposed methodology is based on the application of Successive Linear Programming (SLP) and the decomposition scheme by areas is developed through the Dantzing-Wolfe method. To show the robustness and efficiency of the proposed approach a three-area system is used, in which each area corresponds to an IEEE118-bus test system. The problem is solved in a centralized and decentralized fashion obtaining identical results. [ABSTRACT FROM AUTHOR]

This paper considers the three-echelon uncapacitated facility location problem (TUFLP), which consists on both defining the flow of products from manufacturing plants to clients via a set of warehouses and the location of such warehouses. The objective function is to minimize the total cost of warehouse location and production and distribution. Since the problem is NP-hard, this paper proposes a Greedy Randomized Search Procedure (GRASP) to solve the single-item case. Computational experiments are conducted using known instances from the literature. Results show that the proposed algorithm performs well obtaining very good solutions (and even optimal values) in less computational time than an exact method based on mixed-integer linear programming. [ABSTRACT FROM AUTHOR]

There are many equipments that work the most part of their time in transient regime; therefore, in the design of their drive systems must be employed different methodologies to when, they work in stationary regime. In this paper is shown the application of two distinct methods to the design and selection of the components of an drive system for rapid movements. The Transient Power - Double Kinetic Energy Method and Torque - Time Constant Method were applied to select the drive system of a axis to linear guidance in a punch machine, this case was developed within a project founded by Colciencias. It was necessary to use MATLAB and information obtained from catalogs in order to carry out the required simulations in the evaluation process of the convenience of distinct drive kinds. Also, in this paper is analyzed the complementariness of the referenced methods. [ABSTRACT FROM AUTHOR]

Characterizing physical phenomena existing in rotodynamic pumps has open a new field of study for these machines, where the efficiency on the operating point is being investigated, without significantly affecting other parameters. Research in the peripheral pump made have experimentally proved that Euler's equation does not model its hydraulic behavior because of the toroidal flow that is developed on them, which causes flow recirculation. Due to the above points, this paper develops a methodology for modeling the behavior of peripheral pumps, using a new criterion that was developed for predicting the characteristic curve of the pump and it is based on Euler's equation, which includes two correction factors. The proposed model was validated experimentally to verify that it describes the phenomenon according to the mechanical, geometrical and hydraulic variables involved of the pump. An optimizing process was realized using the corrected Euler's model, and the results are compared to actual pump curve thus is proved that the obtained hydraulic power is improved. The previous statement will allow predicting the gain on the performance of peripheral pumps without realizing expensive experimental test. [ABSTRACT FROM AUTHOR]

This paper stands the results for a systems dynamics model, which allows to evaluate the carbon footprint behavior from ureic and nitrogen fertilizers applications on sugarcane crop fields located at Valle del Cauca on a 5 years simulation. As a research methodology, both dynamics Nitrogen Cycle and the IPCC Guidelines were studied in order to estimate GHG emissions. The main result presented that transition and organic sugarcane crops have a lower level of GHG emissions than a commercial sugarcane crop, with a decrease of 71% and 36% respectively. Through Sensitivity Analysis, since fractional fertilization doses into two times, it is not possible to observe GHG emissions reduction on both medium and long terms. However, considering the suggested doses due to soil characteristics under study and the sugarcane crop cycle, significant levels of emissions reductions were obtained in commercial and organic crops, corresponding on average 21% (plant crop) and 32% (second ratoon crop). Finally, we conclude on the significance of adopting strategies for fertilization in order to increase productivity and to reduce environmental impact. [ABSTRACT FROM AUTHOR]

An approach to recycle lead from spent lead-acid batteries by using citric acid and EDTA has been studied in this paper. This novel method would provide an alternative way to treat the Colombian national resources and contribute to the mitigation of the environmental impact generated by Pyrometallurgical processes currently implemented in the lead acid battery recycling industry. The methodology followed to achieve the project objective was the following: selection and preparation of the material coming from recycled batteries; characterization of the material to be leached; Thermodynamic analysis of the possible reagents or leaching agents and finally a stage of leaching of the material from the lead batteries. The results indicate that the solid material of batteries of lead-acid, is constituted in its great majority by PbSO4 and PbO2. With the thermodynamic stability analysis of the formed lead complexes it is determined that the conjugate base of the citric and ethylenediaminetetraacetic acids (EDTA) form stable lead complexes in the water stability region. In the leaching tests, lead extractions of 77 % were achieved with the citrate ion and 99% with the EDTA ion. [ABSTRACT FROM AUTHOR]

This paper presents a performance analysis of decoupling methods considering its effect in the global system and the control system performance. The system performance was studied using static gain (DGE), approximation dead time (DTM) and feedforward (DAA) decoupling methods. As study case a multivariable (2x2) first order plus dead time model of a Wood and Berry distillation column was used. The performance of the decoupling methods were analyzed for modelling errors in the parameters: static gain (K), time constant (τ) and dead time (t). Decoupling techniques were evaluated using a PID control scheme strategy, testing the control system robustness against modelling errors and set point changes. It was proved that for static gain (K) and time constant (τ) parameter changes, the feedforward decoupling (DAA) presents better performance using the IAE criteria. The effects for dead time changes are not significative, showing IAE variations of 0,05% for distillation column set point changes. [ABSTRACT FROM AUTHOR]

This paper shows the design of spur gears that uses special features in the layout of the job profile of the teeth. The special profiles are defined by mean of potential functions, while the conjugates profiles are calculated by polynomial functions, to ensuring compliance with the basic law of meshing. The designs of the gears with special profiles are compared to an equivalent standardized modular gear. The Ansys Software is used for modeling the equivalent Von Mises maximum stress, in order to perform the estimation of fatigue life in the gears. The main results of this research is found that the use of special profiles can reduce the equivalent von Mises maximum stress in the transmission system by up to 5.4 %, which is an element that enhances the safety factor in the couple of special profiles, compared with the profile of normal module system; it becomes in a prolongation of life to being gear damaged. [ABSTRACT FROM AUTHOR]

The recording of brain electrical activity has led to a greater understanding of different neurophysiological states, has even made possible the diagnosis of some neuronal disorders, hence the importance of characterization and understanding of the different morphologies that may have electroencephalography signals (EEG). The mathematical modeling of biomedical signals facilitates the development of simulators that can be useful as medical training tools on computers or mobile devices. This paper presents the autoregressive (AR) modeling and simulation of EEG signals in different physiological states: seizures, resting with eyes open and eyes closed, and also under the presence of some of the most common artifacts: muscle, eye blinking, electrode “pop”, and 60-Hz. The performance of the models has been validated in the time domain using the percentage of fitting (FIT), which was always above 70%, and in the frequency domain through energy of the characteristic frequency bands of the EEG. The modeling methodology, figures of simulated signals and the values of the parameters evaluated are presented. The wide variety of EEG signals modeled allow the development of brain signals simulators for training of medical personnel, and also for the analysis and characterization of EEG signals. [ABSTRACT FROM AUTHOR]

This paper present the results of corrosion resistance of commercial coatings of chromium oxide Cr2O3 deposited by thermal spray on phosphor bronze substrates with three methods of surface preparation: shot blasting with sand, blasting metal with alumina and polishing with abrasive disc, the three surfaces were prepared with and without base layer. The roughness of the deposited coatings was determined by confocal microscopy and the surface morphology was assessed by scanning electron microscopy (SEM); the crystal structure was determined by X-ray diffraction (XRD) and the corrosion resistance was evaluated via electrochemical impedance spectroscopy (EIS). The results of confocal microscopy showed that the surface roughness has a maximum value of 19,831 µm; XRD analysis showed that the coatings have the same crystal structure of the powders; SEM analysis shows that the surface is porous and inhomogeneous. Finally, the EIS results, reveal that prepared surface with blasting had the best corrosion resistance. [ABSTRACT FROM AUTHOR]

This paper presents a fault diagnosis for opening phase in the stator of a synchronous permanent magnet motor (MSIP) using the finite element method (FEM) in 2D. The analysis was based on the behavior of the responses of the motor variables in steady state under normal operation of the machine, as well as their behavior in transitional and post-failure state. This analysis is done with the aim of categorizing the type of fault according to the content of harmonics in the currents of the stator. Five diagnostic methods known in the literature were used to determine the type of fault just observing the content of harmonics in the stator currents. The diagnostic methods used were: 1-Fast Fourier Transform, 2-Geometric place of the Park Vector, 3-spectral density of energy, 4- Multiple Signal Classification and 5-Method of the Impedance of Reverse Sequence. The results found were consistent for the same fault. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a group of neurological disorders caused by a deficiency of dopamine in a brain structure called substance nigra reticulata (SNr). Deep Brain Stimulation (DBS) of subthalamic nucleus has proved to be a successful treatment for this pathology. DBS modulates the neuronal activity with electrical fields. However, the distribution of the voltage generated in the brain by the stimulating electrodes is not well known. Knowledge of the electrical potential generated by DBS is necessary to find optimal stimulation parameters that deliver the best clinical results and minimal side effects. In this paper, we propose a methodology for estimating the electrical potential based on processing of magnetic resonance image with diffusion tensor (MRI-DT) for specific patient analysis and the finite element method for solution of model equation, in contrast to another similar works where it is employed generic and homogeneous models. Results are consistent with previously outcomes reported in the state of the art and they allow to establish that tensorial model for electrical conductivity is more accurate and detailed to perform DBS simulations, in comparison to generic models with homogenous conductivity. [ABSTRACT FROM AUTHOR]

Elicitation is an activity of requirements engineering that retrieves relevant information about the problem domain and stakeholder's needs to form the software product requirements. to evaluate the elicitation effectiveness is necessary to know and model the influence of the context in which this process is carried out. this paper presents the state of art about the requirements elicitation process, especially on how contextual factors and participants are represented or modeled. to do this, we conducted a systematic mapping of research articles and related books on any methodology or elicitation process model. The study identified thirteen proposals presenting little empirical validation. In general, these works do not include contextual aspects such as characteristics, needs and expectations of stakeholders, characteristics of the problem and solution domain, organizational culture and domain experience of analysts. This situation prompts the authors to develop, as future work, a unified model to address these issues in the elicitation and guide to requirements engineers. [ABSTRACT FROM AUTHOR]

This paper proposes the identification parameter for a human migration model among five Colombian regions. For the identification of parameters an optimization approach is employed where we propose two objective functions. The results obtained with the objective functions are statistically analyzed. The methodology for data analysis employs parametric or non-parametric tests depending on the fulfillment of the assumptions of normality and homoscedasticity (equal variance). To adjust the model, two approaches to the objective function are used. The first considers the total number of population and the second uses the number of inhabitants in each region. By carrying out statistical analyzes, a better adjustment model is observed when considering the number of inhabitants in each region. [ABSTRACT FROM AUTHOR]

The main purpose of this paper is to develop a hybrid genetic algorithm in order to determine the lot sizes and their production scheduling in a single machine manufacturing system for multi-item orders, the objective function minimizes the sum of holding costs, tardy costs and setup costs. The problem considers a set of orders to be processed each one with its own due date. Each order must be delivered complete. In the scheduling are considered sequence dependent setup times. The proposed hybrid genetic algorithm has embedded a heuristic that is used to calculate its fitness function. The heuristic method presents a modification on the optimal timming algorithm in which are involved sequence dependent set up times. A design of experiments is developed in order to assess the algorithm performance, which is also tested using random-generated data and results are compared with those generated by an exact method. The results show that the algorithm achieves a good performance in both solution quality and time especially for large instances. [ABSTRACT FROM AUTHOR]

This paper presents the development of an antenna with circular polarization and double resonance using a substrate of low dielectric constant and low price, showing comparable results in front of conventional designs. The design is made up of two rectangular patches isolated by an air gap including two triangular cuts and two parasitic patches located in the opposite direction giving a certain degree of additional freedom which allows a suitable axial ratio and an acceptable coupling to the desired frequencies. The antenna was optimized by means of parametric analysis carried through diverse variables which belong to geometry. The implemented prototype allows the simultaneous operation of the antenna in the GPS (Global position systems) bands of 1,227 GHz (band L2) and 1,575 GHz (band L1). The antenna shows a measured impedance bandwidth of about 18,03MHz (fc1 = 1,227GHz) and 17,66MHz (fc2 = 1,575GHz), for VSWR ≤ 2:1 (Voltage Standing Wave Ratio), the simulated results for antenna gain were of 5,4dBi and 6,8dBi and axial ratio of 8,1MHz and 10,2MHz in the L1 and L2 bands respectively. The numeric simulations agree well with the measurements on the experimental prototype proving the antenna behaves according to what was expected. [ABSTRACT FROM AUTHOR]

This paper presents a method of approaching business process integration, by taking into account contextual information related to architectural scenarios and levels of integration. The approach is validated through a case study related to the coffee industry. Based on this work, it can be concluded that the more information related to the context and its relationship to the domain and processes, it is possible to avoid unnecessary updates on processes and their variants are made. [ABSTRACT FROM AUTHOR]

In this paper, the refrigerant condensing system in the plastic bottles blowing area at Rum industry is presented. Target values of temperature and water quality should be obtained for a good process. Rejected heat at the blowing machine and the water low at the condenser were calculated. Refrigeration cycle COP was 2.44, with 51% relative efficiency. Refrigeration cycle was simulated using HYSYS. Influences of pressure and refrigeration on the cycle parameters were analyzed. Three variants were evaluated in order to improve the refrigeration cycle: a plastic forced-draft cooling tower, 2.5 m² diameter and 6 m height; a cooling pond, 100 m and the substitution of the refrigerant. The best variant was number 2, with $21 508 as investment with IRR 44.9%, higher than 12%, and ROI 53.2%, higher than 30%. The investment is recovered in a year. [ABSTRACT FROM AUTHOR]

The industrial development linked to the growing addiction to consumption, obsession with fossil fuels, and general desire for short term proit, cause a certain insensitivity to more sustainable alternatives. The construction industry is a sector in which the incorporation of various types of waste presents as favorable. Three types of waste with different characteristics and origins have proved attractive and advantageous for many developing countries. They are incinerated municipal solid waste, bagasse ash from sugar-cane and sisal fiber. The aim of the paper was to realize a literature review of the characteristics, use and importance of these residues as application in construction. The interest in the re-use of these waste materials as raw material in mortar and concrete allows for proper disposal and minimizing the generation of waste, moreover, would no longer be the primary cause of problems relating to public health and the environment. Fortunately, there is a tendency among researchers to stimulate the search for new raw materials that come from cleaner and renewable sources. All studies referenced in the article showed the feasibility of using sisal fiber and residual ash for the manufacture of concrete and mortar. [ABSTRACT FROM AUTHOR]

This paper presents the design, implementation and validation of a laser system for 2D detection of obstacles, indoors and outdoors, using laser radar of Allen Bradley Company (Scanner Safe Zone Laser Multizone). A method for deduction of data frames between the laser radar equipment and proprietary software Safety Coniguration & Diagnostic is proposed. We communicate the laser radar with Player software, enabling its use for robotic applications. We design and implement a software system that lets you use the obstacles 2D coordinates scanned by the laser radar, both text and graphics form, allowing to use it in other applications without limitation. The system is validated tests to measure distances in indoor and outdoor, outdoor obtaining as results, between 94 cm and 5120 cm, an average error of 3.32 cm and interior, between 30 cm and 1500 cm, an error through 0.93 cm. [ABSTRACT FROM AUTHOR]

This paper presents the results of statistical analysis of network traffic (in bits per second) from and to one university web server. Statistical analysis allows to know the hourly traffic trends and to establish a baseline for normal behavior. It documents, in addition, statistical goodness-fit tests results and analysis of variance, which provide elements that enhance the definition of the baseline. Finally, the outcomes are analyzed to determine its usefulness as intrusion detection mechanism or situations or behaviors that could suggest anomalies or atypical traffic. [ABSTRACT FROM AUTHOR]

Among the technologies for clean energy generation, wind turbines are one of the most advanced. Due to stochastic behavior of the wind, a proper control action must be exerted over these turbines in order to get a better use of the output power. A propel control action usually implies the knowledge of the system dynamics, and that is why the identification stage is also crucial. In this paper, the authors propose a robust statistics dual Kalman filter for identification of a wind generator. Although dual Kalman filter (DKF) has been used in system identification, its performance heavily depends on the absence of outliers in the measured data. However, outliers might be easily produced during the data acquisition stage. In this study, the authors show how by combining the DKF and the robust statistic Kalman filter, the problem of outliers in systems identification can be avoided. The method was implemented in Matlab R2009a®. Results for the identification of a wind generator working online are shown and compared to the performance of dual Kalman filter. [ABSTRACT FROM AUTHOR]

This paper proposes an alternative linear control technique to maximize the energy capture in a horizontal-axis wind turbine. The proposed strategy is based on Generalized Proportional Integral (GPI) controllers supported by the active disturbance rejection approach, which allows asymptotic tracking of a rotor speed reference trajectory without exact wind turbine model knowledge. The proposed methodology controls the tip-speed ratio, via the rotor angular speed, to an optimum point at which power coefficient is maximum. Several simulations are performed on a 4.8MW wind turbine benchmark model in order to validate the proposed control strategy and to compare it to a classical controller. The simulation results show that the proposed control strategies are effective in terms of power capture and robustness. [ABSTRACT FROM AUTHOR]

This paper presents the development of an information system for the collection and management of relevant information about vital signs such us blood pressure, heart and respiratory frequency, and oxygen saturation in the blood of a patient. The implementation of this system is based on a Web platform, allowing expert medical specialists to monitor their patients remotely via Web in real time in order to give indications to the medical personal who are with patient. [ABSTRACT FROM AUTHOR]

The purpose of this article is to present a reference framework in the models and configurations of agricultural supply chains, specifically in perishables. The review was based on information research in the databases "ISI Web of Science", "Scopus" and "Science Direct", and the selection criterion of topics of interest. The paper presents some approaches to modeling and configuration of supply chains and the impact of the territory in their planning. The exploration established that the issue requires further study about configurations and their implications, for the design of models to improve logistic processes in agricultural supply chains of multiple producers, with diverse geographic locations in rural areas and needs to decrease operating costs. [ABSTRACT FROM AUTHOR]

Emerging applications in the area of wireless sensor networks that include a wide variety of scenarios typically involve a signiicant number of nodes deployed in a wide area. To ensure proper communication between the network nodes to the base station, the messages are propagated by intermediate nodes, so a route with multiple links is established. In general, sensor nodes are characterized by limited resources; therefore it is essential to use protocols that ensure not only communication but also that save the most energy while providing scalability. Different routing protocols have been proposed for WSNs, but the reactive routing algorithms have shown be more energy eficient, which makes them suitable for wireless sensor networks. In this paper the performance of the reactive type protocol (Ad-Hoc On Demand Distance Vector) is evaluated under the simulation platform OMNeT++ through different scenarios. The AODV protocol has been chosen by the performance superiority comparing with other reactive protocols reported in the literature. The protocol has been evaluated under the following metrics: packet delivery rate, average end-to-end delay, routing overhead and energy consumption. The results show that AODV reduces their performance when the number of nodes increases, consequently it restricts the network scalability, further results show that the spatial distribution of the nodes affect on the performance of the protocol, speciic in our work, the uniform distribution shows better results. [ABSTRACT FROM AUTHOR]

This paper reviews the literature on the statistical design of control charts for autocorrelated data and presents approaches proposed by several authors over the last 20 years, according to three categories. The first one relates to residuals-based control charts, the second corresponds to modified control charts and models based on original observations that aim at reducing the complexity of residuals-based control charts. The last category briefly reviews data mining techniques applied to correlated statistical processes. In addition, future research areas are identified to support researchers interested in this line of knowledge. [ABSTRACT FROM AUTHOR]

This paper reviews the literature on the statistical design of control charts for autocorrelated data and presents approaches proposed by several authors over the last 20 years, according to three categories. The first one relates to residuals-based control charts, the second corresponds to modified control charts and models based on original observations that aim at reducing the complexity of residuals-based control charts. The last category briefly reviews data mining techniques applied to correlated statistical processes. In addition, future research areas are identified to support researchers interested in this line of knowledge. [ABSTRACT FROM AUTHOR]

This paper presents the advantages of a pseudo-periodic surrogate data method to determine whether there exists an additional dynamics (nonlinear correlations) in a pseudo-periodic time series, since classic surrogate data methods used to detect nonlinearity are limited to stochastic-like data. Likewise, Lempel-Ziv complexity and Sample Entropy are introduced as discriminating statistics for null hypothesis testing. The first is based on the counting of different sub-sequences in a time series while the latter is based on a measure of signal irregularity. According to this, an effective methodology is proposed for speech signal processing using the KayPENTAX database. Experimental results showed that both statistics are able to reject the null hypothesis for the signal under analysis. Therefore, it is possible to conclude that there is an additional dynamics in the speech signals other than the pseudo-periodic behavior. Particularly, it was found that the Lempel-Ziv complexity is able to differentiate between signals with slightly different dynamics. [ABSTRACT FROM AUTHOR]