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In this paper the effect of a microencapsulant binary system composed by sodium alginate (SA) and high acyl gellan (HAG) in the protection of Lactobacillus delbrueckii under simulated gastric conditions was evaluated. Microencapsulation is a technique that involves wrapping an active ingredient in order to protect them against deleterious environmental conditions. The results indicated that it is possible to maintain the viability of Lactobacillus delbrueckii at 50% after 4 h exposure to simulated gastric juices when AS and HAG are used as wall system. The free microorganisms completely lose their viability at 180 minute exposure. Therefore, microencapsulation can be a useful technique in the production of functional foods maintaining therapeutic levels of probiotic bacteria. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of optimal location and sizing of distributed generation in distribution systems. For such an assessment the following search techniques were implemented: i) simulated annealing, ii) variable neighborhood search, iii) genetic algorithm and iv) hybrid genetic algorithm. Two objectives have been considered in the optimal location and sizing problem: the minimization of electric power losses and the improvement of voltage profile. To compare the effectiveness of the methodologies a 34 bus distribution test system is used. The correct location and sizing of the distributed generation allowed substantially improving the voltage profile of the network and reducing in 80% the power losses in the test system. [ABSTRACT FROM AUTHOR]

In this paper we present a new algorithm for finding the convex hull C(P) for P sets of n points in R2. This problem has been widely studied in computational geometry and has important applications in engineering and other fields of knowledge. The proposed algorithm is based on a directional search of supporting hyperplanes and a variant which includes separating hyperplanes to reduce the number of evaluated points, ignoring the interior ones. The application of the proposed algorithm is illustrated using an example. The complexity of the algorithm obtained is O(max (nvo; nvo)), vo ≤ v ≤ n y vo ≤ v ≤ n, where v is the number of vertices of the convex hull. [ABSTRACT FROM AUTHOR]

This paper presents a methodological proposal to motivate and facilitate the construction of learning environments for the formation and training about decision-making, management and research of agriculture and livestock processes. The methodology is supported by simulation models which, by using non-linear mathematics and computing supported by System Dynamics, allow the generation of different scenarios for approaching, the dynamic complexity of the phenomena under study. The proposal is useful and convenient for non-expert and researchers that in interdisciplinary groups decide to study the complexity of real productive systems. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to obtain a global index of safety in airport runways, with criteria based on safety events. Events were weighted based on the cardinal data extracted from the perception of an expert on safety risks, using the Swing Weights method. The multi-attribute value theory to group the different criteria in a global index was employed to analyze the evolution of the safety levels. This approach was applied to the operations of the São Paulo-Guarulhos International Airport. Trend analyses were done to highlight the most urgent indicators to carry out actions to increase the safety levels. The results were considered to be consistent, contributing to the continuity of its practical application in the management of airport safety. [ABSTRACT FROM AUTHOR]

In this paper a study of some mechanical properties of two varieties of sweet potato (yellow and red) is presented. This with the aim of obtaining data required in process engineering calculations, and in handling and storage of the product. Different tests were used (penetration, compression and bending), to estimate parameters of maximum penetration stress, stress and strain at fracture and modulus of deformability. The texture analyzer TA.XT plus Stable Micro Systems was used. It is concluded that the red and yellow variety have very similar values of compression stress (0.77 and 0.75 MPa) and that the deformation that must be applied to cause fracture are also very similar (21.5 and 20.5%). With respect to the fracture stress, significant differences between the two varieties were observed. [ABSTRACT FROM AUTHOR]

This paper presents the mathematical derivation of the power losses by conduction in single phase H-bridge inverters controlled by Sinusoidal Pulse Width Modulation (SPWM). The development of the mathematical equations for voltage and current through the semiconductor in its conducting state is presented and the power dissipation is calculated. The power loss equations found depend on the characteristics of the modulation used and on the parameters of the load. Through simulations and experimental validation, curves showing the validity of the equations and their approaches in accordance with the conditions of the test were obtained. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for optimal Distributed Generation (DG) allocation using a hybrid genetic algorithm. In this case, the objective function is the minimization of power losses. The proposed algorithm involves an artificial neural network to evaluate the fitness function and a local search subroutine that allows the algorithm to explore a wider search space, and eventually, escape from local optimal solutions. The proposed approach was tested on a 34-bus system showing that the proper allocation of DG units allows the reduction of active power losses and the improvement of voltage profile. [ABSTRACT FROM AUTHOR]

This paper shows the behavior of the energy of normal modes of vibration, which constitute an elastic wave, when it undergoes dispersion in a granular media. For this, scattered radiation patterns between different pairs of modes are plotted and analyzed, highlighting the main directions of dispersion. For this, cross sections of modal dispersion W(iki, jkj) obtained by Trujillo and coworkers in 2013 was used. The normal modes implemented are the solutions of the problem of free vibrations of an elastic, homogeneous and isotropic plate, namely, horizontal shear modes and Lamb, which in turn can be symmetric or antisymmetric. This work aims to contribute to the understanding of the behavior of the internal structure of granular media, as well as potential applications in fields such as, soils mechanics, geophysics, seismology, and oil exploration, among others. [ABSTRACT FROM AUTHOR]

This article provides a methodology for calculating the health index for oil-paper insulation system in power transformers with rated voltage between 69kV and 230kV, using fuzzy logic. The article also provides a detailed review of the existing limits of acceptance, according to the present standards and for each of the six input variables: moisture content, acidity, dielectric strength, dissipation factor oil, dissolved gas and furan content. With this information, the membership functions are obtained and the six input values are related to the output value, which represents the health index of the transformer. Using data provided by a company of the Colombian electricity sector for 18 power transformers the health index is calculated and the results are analyzed. The health index could be useful for establishing a ranking of the state of power transformers with the aim of better assigning resources and maintenance activities. [ABSTRACT FROM AUTHOR]

In this paper the erosion rate of ceramic coating using a software application which includes parameters related to the erosive wear process is determined. The application was done using SharpDevelop 4.2, a free and open integrated development environment in C# language. Moreover, the program makes use of the open source libraries MySql to manage the data containing the erosion parameters and ZedGraph to plot the data. Erosion of layers of titanium nitride (TiN) and chromium nitride (CrN) deposited on AISI 4140 steel substrates was experimentally studied and results compared with the software results. Results show that the erosion rate reaches its maximum value when the angle of incidence is 90° and that experimental and calculated values of erosion rate are well correlated. [ABSTRACT FROM AUTHOR]

This paper proposes a geometric strategy for generating optimal navigation paths for robots in static and observable environments. As design principles for the algorithm, robustness, simplicity and low computational cost were established. The algorithm uses image segmentation into regions as architecture support. These regions are constructed from the vertices of the obstacles, which define two independent sets of regions. From the boundaries between regions we build a set of secure navigation points, points that are the basis for generating a bank of secure paths. Finally, a search algorithm selects, from this bank, the path that the robot will follow. The algorithm has been successfully evaluated by simulation on over 30 environments, finding a suitable path in 100% of the cases. [ABSTRACT FROM AUTHOR]

This paper presents the development of an information system using XML retrieval, as a tool to support the management of work orders in small and medium size enterprises (SME) from Cartagena to generate information to support decision making in the process outlined. The methodology used was the development of a structure of the general process of software engineering. The usefulness of the software was determined by the design, construction and implementation in the SME, validating its use through a usability test. This allowed measuring the level of acceptance of end users, thus saving costs in managing archived files and facilitating decision making. Based on the results it was possible to conclude that the process of work order management was improved by implementing the information system. [ABSTRACT FROM AUTHOR]

The main objective of this paper was the development of software to contribute to the control of documents generated during the implantation process of an Information Security Management System (ISMS). The software allows receiving, managing and organizing the documents generated on the process of implantation of ISMS. To support this software, a model that defines the management actions that are necessary for approval, review, update, states and readability of documents through the life cycle of the ISMS was designed and implemented. As a result, a document management module that allows the control on documents during the implementation process, working under the standard ISO 27001 was developed. [ABSTRACT FROM AUTHOR]

This paper proposes a new procedure for the design of snubber RCD in power electronic circuits to reduce the peak transient voltage when the power switch is turned off. The procedure involves a method for the determination of parasitic elements in the switching circuit and the mathematical deduction of design equations. The proposed procedure is a useful tool for the analysis and design of snubber RCD circuits, used in the majority of power electronic circuits. The design equations obtained in this work allow the theoretical calculation of the value of the capacitor and of the resistance of the snubber RCD based on the parasitic reactances of the implemented circuit and the maximum operating voltage of the switch, allowing the verification through simulation of the dynamic performance of the circuit before the experimental implementation. The procedure and the design equations are verified in the laboratory, corroborating the consistency of the theoretical analysis with the experimental results. [ABSTRACT FROM AUTHOR]

In this paper a numerical index for quantifying state controllability for continuous and smooth nonlinear systems is proposed. With information obtained from the reachable and controllable sets, a reversible set at time t for a given system is defined. Size and shape measurements of a reversible set in an n-dimensional space are proposed allowing state controllability on a scale from zero to one. Procedures to compute such indexes are detailed. State controllability index is computed for three study cases verifying its correspondence with real controllability. The inclusion of time and admissible input constraints for state controllability analysis of nonlinear systems showed to be a useful tool for real control system implementation. [ABSTRACT FROM AUTHOR]

In this article three methods (multiple replications, non-overlapping batches and spaced batches) to estimate the expectation, the variance and the 90%-quantile of the steady-state waiting time in an M/M/1 queue are compared. Our comparison is based on the empirical coverage, bias and relative error of 90% asymptotic confidence intervals from 1000 independent replications of a simulation-based estimation. Experimental results show that all three methods provide similar (and valid) empirical coverage for the estimation of the expectation, variance and quantile; and the method of non-overlapping batches provided smaller bias and relative errors than the other two methods. In addition to this, an example of a continuous state-space Markov chain that is ergodic but non-geometric, is presented. For this case asymptotically valid confidence intervals by using the methods considered in this paper are also obtained. [ABSTRACT FROM AUTHOR]

This paper provides an introduction of the fractional Fourier transform (FRFT) and describes the process of implementing the discrete fractional Fourier transform (DFRFT) based on the spectral decomposition of the discrete Fourier transform (DFT) matrix operator. In the last decade, the FRFT has been considered as a useful tool for signal processing applications. In the theoretical evolution of FRFT, many definitions of the DFTFT have been proposed in the literature. However, few definitions of the DFRFT present similar results to those provided by the FRFT without losing its most important properties. Therefore, some theoretical clarifications are made with respect to previous works. Moreover, the relationship between the FRFT and the DFRFT is also shown. Finally, in order to promote the use of this transform in the signal processing community, some algorithms of the DFRFT with low computational costs are described. [ABSTRACT FROM AUTHOR]

The aim of this paper is to propose a customized recommendation model of educational resources for virtual courses that incorporates the benefits of ubiquitous computing and intelligent agents. This model is intended to provide relevant and personalized information to students about their virtual courses planning, online assessment, search and retrieval of learning objects. The methodology used for the construction of the system is MAS-CommonKADS which offers useful models for the phases of conceptualization, analysis and design expressed through artifacts provided by the Agent Unified Modeling Language (AUML). The prototype developed exhibits intelligent proactive and deliberative agents that allow the search and recommendation of information adapted to the student's profile. To validate the system a testing phase on a learning scenario was performed which demonstrate the effectiveness of using this kind of technology within ubiquitous virtual learning environments. [ABSTRACT FROM AUTHOR]

This paper proposes a biometric system using stereo images to improve the security performance of conventional face recognition systems, by discriminating between 3D real and forged 2D faces images, using the tridimensional information provided by the stereo images. Once the system determines that the face under analysis is an authentic 3D image, each stereo image is characterized and independently processed using three feature extraction methods. Then a fusion method is required to combine the information of both images. To this end three fusion methods are analyzed to achieve a more robust face recognition system. The experimental results show that by performing the fusion of the data extracted by wavelet transform, before going to the classification step, better results are obtained. [ABSTRACT FROM AUTHOR]

This paper discusses a Back to Back (BTB) power converter based solution for the management of power flow between two interconnected AC systems. The main objective of this work is to show the advantages of the BTB converter to manage the active and reactive power between two interconnected AC systems. The active and reactive current components are decoupled through a linear control strategy allowing the active and reactive powers are independently controlled. The control strategy is developed on the direct- quadrature synchronous reference frame (DQ) considering a balanced three-phase three wire system. The performance of the BTB converter for power flow control is demonstrated through simulation and experimental results using a 3kVA power converter. [ABSTRACT FROM AUTHOR]

This study analyzes the scientific production in the field of business studies in Chile and Brazil. The methodology is based on scientometric tools, using as sources 7955 papers published in Scopus indexed journals between 2004 and 2013. In summary, the results indicate that although in both countries the scientific production has significantly increased, a reduction of the impact of these articles is detected. In addition, there are differences between Chile and Brazil associated to cooperation with other countries, the variety of journals where studies are published, and the structure of the ranking of the institutions that publish. The main conclusions indicate that research in this area is carried out in universities, cooperation between countries is significant in this scientific production, and dissemination is carried out mainly through regional journals. [ABSTRACT FROM AUTHOR]

In this paper the basic structure and design of a torque controller for an electric vehicle driven by induction motor is presented. The basic structure of the electric vehicle in question and its mathematical model is presented first. After that, the operation principle of the conventional direct torque control is analyzed and from this a new controller with fixed constant switching frequency is designed. To generate the switching pulses sine PWM is used instead of the hysteresis comparator and switching table commonly used in direct torque control. Finally, simulation comparison was performed. This shows that better performance was achieved with the proposed controller with lower torque and flux errors, and lower torque and stator current ripple. [ABSTRACT FROM AUTHOR]

In this paper the influence of Lactobacillus acidophilus microencapsulation using a gelling binary system, in obtaining of soft yogurts, was studied, evaluating bromatological and rheological parameters. The results show that L. acidophilus microencapsulation increases viscosity and viscoelastic yogurt characteristics. However, the sensory analysis conducted did not show differences between yoghurt elaborated with L. acidophilus microencapsulated and yoghurt in free state. With respect to the physicochemical analysis, changes in the lactose, fat and protein values suggest an increase in the metabolic activity by L. acidophilus microencapsulated, which is evidenced by the increasing number of bacterial cells obtained at the end of the incubation period. Therefore, bacterial microencapsulation can be an interesting technique to perform the inclusion of probiotic bacteria in acidic food systems, without causing loss of the sensory attributes of the food product. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize the physicochemical properties, texture and microbiological quality of sausages sold in the city of Cartagena (Colombia). The street food vending in Latin America and the Caribbean is a phenomenon of great sociocultural, economic and health importance in the region, so the subject deserves a study like the one presented ion this paper. Proximal, microbiological and textural analysis of 30 samples from supermarkets Bazurto market and street vendors located in the city of Cartagena were performed. The sausages sold in supermarkets only meet the premium quality according to their physico-chemical content, and they are the only ones that meet the microbiological criteria set by the Colombian Technical Standard. The sausages evaluated have a profile similar to those reported by other authors for this type of product texture. [ABSTRACT FROM AUTHOR]

In this paper, it is proposed to apply the discrete cosine transform (DCT) and the compressive sampling (CS) techniques to audio signal compression. Using spectral analysis and the properties of the DCT, audio signals can be treated as sparse signals in the frequency domain. This is especially true for sounds representing tones. Thus, it is proposed using the DCT as a preprocessor to obtain a sparse representation in the frequency domain, combined with CS to obtain an efficient representation of the signals. It is shown that the subsequent application of CS represents the signals with less information than the well-known sampling theorem. [ABSTRACT FROM AUTHOR]

This paper summarizes the results on the modeling and simulation of an industrial rotatory kiln for clinker production. The proposed one-dimensional model includes several sub-models for simulating the variation of the bed height in the kiln, the reactive mass and energy balances in the solid and gas phases and the coal combustion. The shooting method was chosen for iteratively solving the coupled models. The model predictions of both reactant and products concentrations and gas and solid phase temperatures are in good agreement with the industrial data within deviations lower than 7%. Additionally, it was possible to quantify the thermal inversion phenomena, which occurs when the melt gets colder after having passed the peak temperature. Based on the results, it can be concluded that the proposed model is a useful tool for analyzing the performance of the rotatory kiln. [ABSTRACT FROM AUTHOR]

In this paper an interpolation method based on (k,n)-threshold secret image sharing (SIS) scheme is proposed, in which the secret data are any binary data, such as images, audio, video, document and even executable files. The proposed scheme uses Lagrange polynomial in the Galois Field GF(28) to encode and decode the secret data in a lossless manner. The shared data are hidden into n camouflage images. In the decoding stage, at least k (≤n) camouflage images are required to reveal the secret data. To increase the payload of the secret data, Lagrange interpolation is solved in an iterative manner under GF(28). The experimental results show a higher payload of the secret data compared to those of other methods previously reported. Also, the quality of the camouflage images is higher than that of the conventional algorithms when the same amount of secret data is shared. [ABSTRACT FROM AUTHOR]

This paper presents a study and analysis of the importance and implications of the imbalance regulation, by the insertion of distributed generation, on a medium voltage electricity distribution network. The imbalance represents a problem of energy efficiency in electric power systems since it generate additional demands and energy losses For this study, and actual distribution system of the company EPEC in the province of Cordoba, Argentina, was considered. The modeling of the actual behavior by using the ATP/EMTP software. The results show that the effect of the distributed generation is positive in terms of reducing the imbalance in the network. The derating coefficient obtained is a good indicator of the energy performance. It is concluded that it is possible to regulate and reduce the imbalance with the inclusion of distributed generation. [ABSTRACT FROM AUTHOR]

This paper proposes a new adaptive hybrid filter scheme based on the least mean square and the recursive least square algorithms for uniform linear antenna arrays to generate radiation beam patterns. The individual adaptive blocks used to form the new filter are interconnected by the linear array factor to simulate a virtual antenna array and to set the desired direction of the main beam pattern. The completed formulation of the new filter is detailed and its capability to minimize interference signals and adaptive white gaussian noise is evaluated by simulation and compared with other filters. The simulation results showed that the convergence speed and the filtering characteristics of the new model are better or similar to those that make it. In conclusion, the new scheme can generate the main beam pattern to the desired signal direction. [ABSTRACT FROM AUTHOR]

In this paper the modular approach of aspect-oriented programming named join point interfaces or JPI for the Java programming language is discussed. Also, the main differences and advantages of JPI over the classical methodology of aspect-oriented programming for Java (AspectJ) are analyzed with the aim of achieving a modular aspect-oriented programming. In addition, an extension of UML class diagram for the structural and conceptual design of JPI applications is proposed. As a study case, a programming example in AspectJ and JPI, along with a UML class diagram model of the study case, using the modeling proposed in this work, is presented. It is concluded that the proposed class diagram UML JPI allows defining an ingenuous class, an essential element for achieving a complete adaptation and transformation of aspectoriented programming into JPI solutions. [ABSTRACT FROM AUTHOR]

This paper presents the machining strategy implemented in a modular system developed for the conversion of conventional lathes to a numerical control machine. The objective is to make the system simple to install and cheap enough to make it affordable to the local small and medium-sized Enterprise. General characteristics of the developed system are exposed. This work emphasizes in the mechanical and software systems. The machining strategy, implemented in the software, is deeply studied. This strategy makes it easy to manufacture solids of revolution, just with a previous 2D design made in any computer-aided design software. No G code is used. Finally, other chess pieces (a rook and a bishop) are manufactured, and obtained results are compared with those obtained in the previous version of the system. The better performance is verified. [ABSTRACT FROM AUTHOR]

The growth of world food production and the poor distribution of them is analyzed and discussed. The subject is treated considering that the appropriate distribution of food is of paramount importance and proposes a methodology based on mechanics of materials to assist in the decision making process. Food production has increased in many countries, but the number of people has also increased and food distribution has not improved according to the increase in people and foods. Additionally, the food chain is nowadays more vulnerable to environmental pollution. The proposed methodology is based primarily on the establishment of the necessary measures to ensure access to an adequate amount of food, in this chain of humanitarian logistics. The paper concludes with a description of challenges and opportunities for better distribution of food in the world, today and in the future. [ABSTRACT FROM AUTHOR]

In this paper compares studies over routing and wavelength assignment for better some services indicators, such as blocking probability and network utilization. In modern telecommunications are gradually subjected to increased demand, which results in higher requirements in photonic transport networks. This phenomenon forces us improve routing systems, in order to better serve current demand and have capacity of attention of future demand. The comparison is made between the algorithms Genetic Algorithms and Simulated Annealing, both simulated in the optical network NSFNET using wavelength division multiplexing WDM. The results showed that heuristic algorithms are better in dynamic demand and high charge, functioning better under stress. It is concluded that genetic algorithms provide the best solution for future demand. [ABSTRACT FROM AUTHOR]

This paper studies the user satisfaction of a representative sample of urban elderly who receive hearing aids via the GES program (Explicit Health Guarantees). We used the operational construct of the Health Ministry of Chile, MINSAL clinical guideline No. 56 of 2007, named "Bilateral hearing loss in people of 65 years and older who require earphones", and that defines the items to be evaluated. The so-called "International Survey of Use of Earphones CIRUA" was applied. The sample considered in the study was defined as elderly people who have used the device for more than one year since its delivery. Finally, elderly people value the fact of receiving their hearing aids, recognize its usefulness, and appreciate how it has changed their life and their normal routines. They also indicate that falls have reduced falls and indicate that they have at present a better quality of life. [ABSTRACT FROM AUTHOR]

This paper presents the simulation and thermodynamic analysis of an absorption cooling advanced system of the type air-cooled GAX. The study of the system is focused on the thermal conditioning of residential spaces located in regions with extreme hot weather. The mathematical model of the system is solved using a computational algorithm called backtracking. A simulator was developed to evaluate the operational behavior of the system, under different environmental conditions. It was found that the ambient temperature has an important influence on the operating behavior of the system, since efficiency decreased by 20.4% when the temperature changed from 40 to 50° C. It is concluded that the GAX cooling system operated in hot extreme weather is a good alternative option for the thermal conditioning of spaces since it maintains a high performance coefficient compared to conventional systems. [ABSTRACT FROM AUTHOR]

The aim of this paper is to define the test procedures to be followed in dowel-type joints of timber structures, in order to identify their resistant behavior in real situations. A new methodology is developed according to the new European regulations guidelines on real-size specimens, reflecting the main parameters to take into account during the tests and the evolution of the stress-strain relationships. Factors such as wood crushing, dowel bending and rope effect have been taken into account. From the analysis of prototypes, specific fittings and several series of tests on specimens have been prepared to develop the tests with three options. These are: joint with threaded bolt, joint with glued-in rod and joint with washers and nuts, all this with the objective of analyzing the behavior of the different types of connection. [ABSTRACT FROM AUTHOR]

This paper presents a new technique for vulnerability analysis in power systems under multiple contingencies. The model under study is known as the "Terrorist Problem". The main contribution of this work is the formulation and solution of the AC version of this problem, which allows identifying the most critical elements of the power system and gives early signals to the system operator regarding the vulnerability of the system. Furthermore, the AC version of the model allows obtaining more realistic results than the traditional DC model, due to the fact that such version considers the effect of reactive power and voltage magnitudes in the system buses. The proposed model is solved by means of a hybrid metaheuristic technique that combines genetic algorithms with local search. The results obtained using the IEEE RTS - 24 bus test system show the relevance and applicability of the proposed methodology. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of inefficient power flows caused by power converters. Based on the power theory of the IEEE standard 1459 (2010) and starting from the power caused by harmonic currents (DeI), the power DeI_low and DeI_high are proposed for quantifying the inefficient power flows caused by power converters. The power DeI_low is because the existence of low-frequency harmonic currents, while the power DeI_high depends on the number of pulses used in the modulation. An exchange power analysis between the converter, the load, and the semiconductors is presented. There are also included simulation results for a single-phase converter controlled by a Sinusoidal Pulse Width Modulation (SPWM) taking into account the voltage drop in the semiconductors of power switches and changing the number of pulses in the modulation. [ABSTRACT FROM AUTHOR]

This paper shows a method for normal vectors estimation and outlier reduction for point cloud surfaces. This method is based on Robust Principal Component Analysis applying to a sizable neighborhood, estimated according to local geometric featuring. First, outlier reduction is applied by means of a Mahalanobis distance based procedure. Subsequently, a variable size neighborhood is estimated calculating local geometric features. The resizable neighborhood showed to give a more accurate tangent plane estimation than a size fixed neighborhood, allowing accurate normal estimation. The method permits normal vector estimation that is robust to noise, outliers and border and sharp features. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the main technologies for energy storage and use in electrical microgrids. Use of renewable energy sources in electric energy distribution increases instrumentation, management and control requirements, due to the high degree of intermittency and variability that these sources present. Storage systems provide reliability, availability and quality that are required. However, storage system selection must be part of microgrid design, taking into account the goals and the desired characteristics. The analysis shows that the implementation of energy storage systems on a microgrid improves transient response and capacity, increases instantaneous power and allows renewable energy integration. [ABSTRACT FROM AUTHOR]

In this paper definitions for time constraints of steps of a real-time task (RTT) are presented. These definitions were constructed using set theory and functions theory and provided the basis for formalizing the concept of scheduler of tasks as a function that maps from the arrival times set to the start times set on a set of concurrent RTT. This definition is valid for any scheduler and its description does not depend of the scheduling algorithm or of the arrival time of the tasks. As an application, a study on the Rate Monotonic scheduler in which a specific case with time constraints is presented. The set of definitions will allow performing studies of stability, functionality, optimization, feasibility and comparison with other schedulers. [ABSTRACT FROM AUTHOR]

The aim of this paper was to develop a methodology to diagnose the use of personal software process in software industry of Cartagena de Indias, Colombia. In this work, Personal Software Process related model based on a systemic methodology variables were used taking as reference the Humphrey's model in which each subsystem had input and output variables to other subsystems. This work tends to improve the techniques of Personal Software Process taking the first step on a path to the required quality and detected in a previous work presented in the literature. The results showed good practice in companies with defined methodologies for software development in contrast to others who lacked standards for managing of established routines. [ABSTRACT FROM AUTHOR]

In this paper the necessary equations for considering existing network reconfiguration in the disjunctive linear model used to solve the problem transmission expansion planning. In the traditional methods used for solving this problem new transmission lines and two-winding transformers are commonly used as expansion candidates. However, reconfiguration of existing network has not been considered as a valid solution in the classical models. The Garver test system and a Colombian system are used to show that considering network reconfiguration can reduce investment costs of the transmission expansion planning problem. This work shows that an optimization model that includes conventional candidates and reconfiguration produces better expansion signals in the transmission lines of electric power systems. [ABSTRACT FROM AUTHOR]

This paper shows a methodology for evaluating the immunity of a single-phase induction motor to voltage sags by simulations in Matlab/Simulink. For this, a model of a single-phase voltage sag generator was designed and algorithms were implemented, to obtain, model and improves the sensitivity curve of the induction motor with respect to the voltage drop. The implemented methodology is a simple guide to estimate the impact of voltage sags on induction motors. Additionally, the proposed method reduces the amount of voltage sags to which the motors are usually subjected in lab test using other methodologies. [ABSTRACT FROM AUTHOR]

This paper evaluates the fundamental characteristics of the delivering of on-demand television and video contents (packet loss, delay, jitter or delay variation) over an IPTV-IMS platform using real time streaming protocol (RTSP) and hypertext transfer protocol (HTTP) at small scale. This is done with the objective of determining which of these presents the best performance. For this, several cases were analyzed in which the delivered service and the structure of the network were changed and also the data flow. The analysis of the results allowed concluding that for the given conditions, the HTTP protocol presented a better performance, showing lower losses and delay and jitter values within the standards for IPTV. [ABSTRACT FROM AUTHOR]

In this paper, RSVP-TE and CR-LDP signaling protocols in the Generalized Multiprotocol Label Switching (GMPLS) are evaluated based on the design parameters of the physical layer, and packets and wavelength switching. In the simulations, of the signaling protocols the results do not present important discrepancies. The use of the UDP segmentation in RSVP-TE and of TCP in CR-LDP, present differences in the so-called LSP state. Additionally, some characteristics of each of the objects in RSVP that add other functionalities to each protocol. The results show the delay, throughput and jitter, for each signaling protocol, using the GLASS simulation tool. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of proposals for the conceptual modeling of Extraction- Transformation-Loading processes (ETL) and proposals that incorporate security in data warehouses and ETL processes. The method used considers the characteristics of the proposals and their principal activities in the ETL process modeling. Furthermore, considers proposals that incorporate security in the modeling of data warehouses and ETL processes. Considering the lack of existing proposals, it is concluded that is necessary to incorporate security in the ETL processes modeling to assist in obtaining secure data warehouses. [ABSTRACT FROM AUTHOR]

In this paper, the performance of the variables: makespan time, defective fraction due to operator fatigue and direct labor cost, in a job shop manufacturing system is presented. Two methods are compared; the first one blends elements from VEGA and MOGA algorithms (V&M), while the second one corresponds to a weighted sums method (WSM). Applying these methodologies, it was found that the method V&M has a better performance than the WSM. Comparing he variable makespan time (in hours) the first is better by 7.0 %; comparing the variable makespan time (in weeks) by 6.7 %; and comparing the variable defective fraction by 1.4 %. Regarding the variable labor costs, both methods have the same performance. [ABSTRACT FROM AUTHOR]

The objective of the work presented in this paper was to identify predictors of excellence from the employee's point of view (EPV) in a medical center. To do so, a questionnaire with 84 items was designed and applied to a 115 employees of the center. Reduction of scale using Alpha Cronbach test and factors analysis was done and multiple regression analysis to identify the factors significance on the EPV was also used. A reliable and valid scale was achieved with 23 of the items, composed by six factors that explained 77% of the total variance. In the case of study, three of the factors were significant in the regression analysis, in which the model passing through the origin explained a 98.8% of the EPV: director's leadership (34.8%), medical technology (35.4%) and deployment of the training processes (29.8%). The other factors were: nonmedical resources, social support and human resources management. The proposed model offers possibilities to be used in other contexts. [ABSTRACT FROM AUTHOR]