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A study on the alignment process of data of human morphology obtained by laser acquisition devices is presented in this paper. A three-dimensional latest generation digitizer is used and a methodology of alignment for the human morphology data is established. Also, guides on how to solve problems of this alignment are discussed and a comparative study of point clouds processing programs is carried out. RapidForm™, the standard software used for editing data acquired by the scanner 3D is compared with Polyworks™, the alternative to RapidForm™ software used due to its good characteristics for the alignment mechanical parts. Results of the comparison of some software applications are showed. [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]

The objective of this paper is to review the unified modeling language UML sequence diagrams, presenting STAIRS as an alternative way of formalizing UML interaction diagrams, especially sequence diagrams. STAIRS is a formal language for modeling interactive UML diagrams, especially sequence diagrams. The inherent problems of ambiguity that UML models have, including the production of models that are not necessarily corrected, are analyzed. It is demonstrated that STAIRS contributes to reducing this ambiguity. It is concluded that although there are new approaches for software development, such as aspect-oriented development, UML is capable of adapting to these developments. The review and analysis presented in this article could be especially useful for clarifying these aspects. [ABSTRACT FROM AUTHOR]

This paper presents the construction of a model based on system dynamics for describing the behavior of pig market. This with the objective of anticipating possible events, creating scenarios about assumptions and determine whether it is feasible or not to invest in this market in a short to medium term. The proposed model consists of seven cycles considering the different variables involved in the pig market, establishing relationships and the cycles formed between them. The model variables were set using historical data of the market. The results show a high dependence of raw material costs over the earnings and show the stage of breeding as the most profitable scenario. [ABSTRACT FROM AUTHOR]

In this paper the advances done by the research groups of the University of La Serena and University of Concepción on thermodynamic consistency tests of low to high pressure phase equilibrium data of binary mixtures are presented. The main advances of the group consist of the extension of a thermodynamic consistency test previously proposed by the Group of La Serena to mixtures containing an ionic liquid. The method has been especially designed to analyze data sets that do not cover the whole concentration range and is based on the Gibbs-Duhem equation and an appropriate application of equations of state, mixing rules and combining rules. The proposed method allows analyzing single data from an experimental data set and determining thermodynamic consistency or inconsistency of the equilibrium data in all cases. [ABSTRACT FROM AUTHOR]

This paper describes a solution method to the problem of processing n jobs on m non-related parallel machines. It is a linear and combinatorial generalized allocation problem that considered a sequencedependent setup time and dynamic job entry. A genetic algorithm with integer coding and random generation of population, parent selection, crossover and mutation is proposed. There are two descendants per generation that are compared against the worst existing element to enter to population. After a number of generations that is proportional to the product of nxm the solution is generated. The jobs are sequenced on each machine by due date and computational times are acceptable. It is concluded that the proposed genetic algorithm is an effective and efficient solution that focuses on reducing processing time and on meeting deadlines. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to predict functional states in complex processes from the estimation of fuzzy membership degrees. The proposal integrates a static measure, such as the result of a fuzzy classifier trained with historical process data, and an estimation algorithm based on Markov theory for discrete events. The proposal, which can be integrated to the monitoring of complex systems, provides two stages: an off-line training stage to define the fuzzy classifier and the estimator; and an online stage where the classification of the current process situation and the estimation of the next functional state are performed. The proposal for the estimation of functional states allows using any fuzzy clustering method that provides the information required by the methodology. The proposed methodology was successfully tested on a monitoring system for a power transmission line and in the monitoring of a boiler system. [ABSTRACT FROM AUTHOR]

This paper proposes a video watermarking algorithm based on image normalization, motion estimation and perceptual information performed in the baseband domain. The proposed algorithm is designed to survive legitimate operations and malicious attacks, focused on the robustness against multiple video format conversion. Watermark embedding and detection are carried out in the Discrete Cosine Transform domain, and image normalization is used to get geometric invariant feature of video frames. The watermark energy is adapted using perceptual information and motion vectors to get higher imperceptibility and robustness. Computer simulation results show the watermark robustness to the most common video codec conversions, geometric distortions, as well as common signal processing and intentional frame-based attacks. [ABSTRACT FROM AUTHOR]

This paper proposes the implementation of an optimum academic agenda to solve the problem of scheduling a school day in Colombia. This is done by taking into account not only the appropriate assignment of rooms and professors but considering the cognitive rhythms of the students as the most relevant factor in the optimization. The Non-dominated Sorting Genetic Algorithm, NSGA-II is proposed as a solution method. The results show a higher efficiency of the algorithm when compared to other algorithms applied to the same problem and evaluated in the same form. At the experimental level the methodology shows a reduction in academic mortality rates in the groups where the methodology was implemented compared to groups that did not considered the cognitive rhythms of the students. [ABSTRACT FROM AUTHOR]

This paper presents a study and analysis of air pollutants in an area of permanent industrial and agricultural development in Chile. The study considers the watershed of the Aconcagua river including several cities of the provinces of Valparaiso, Quillota, San Felipe and Marga Marga. The information obtained from monitoring networks of air quality that are regulated by the Chilean health and environmental authorities, during the period 1998 to 2008, was used to develop a qualitative method to assess the risk of contamination to human health and vegetation. The method showed areas of high risk to vegetation and human life and other areas that should be declared as saturated zones. It was also demonstrated that it is necessary to establish primary and secondary standards, particularly for some trace elements considering the importance of the area as an exporter of agricultural products. [ABSTRACT FROM AUTHOR]

In this paper, an analysis of structural integrity to the repair of a gas pipeline is presented. The study is based on a simplified two-dimensional finite elements model. The residual stresses of thermal origin caused by the welding process are evaluated considering the pipeline flowing fluid and the pressure exerted by the fluid. Pipelines in Argentina are periodically inspected following the standards of the American Petroleum Institute (API) and specifications, criteria and experiences developed by each plant. The modeling allows determining weakened areas caused by corrosion or by different types of defects or cracks. This allows planning and prosecuting a localized repair within acceptable safety margins. [ABSTRACT FROM AUTHOR]

In this paper the analysis of the impact of Information and Communication Technology (ICT) especially for the Internet service in the area of Ciudad Bolivar in Bogota-Colombia, one of the sectors with the highest poverty rates in the city. The main objective of the study is to gather relevant information to identify the characteristics of the area in terms of technology and basic needs that can be supplied or improved through ICT. To properly characterize the needs of the population, three kinds of surveys were done: household, environment and enterprise. Then, the statistical results of this study are presented, taking into account the permissible error and the estimated confidence level. [ABSTRACT FROM AUTHOR]

This paper presents the design of an expert controller applied to voltage level control in a power system. The use of pilot node concept allows to keep stable the list of controllers against topological changes in the network. To achieve the optimal voltage profile, the Alberta Electric System Operator regulations are used. The controller validation is performed by simulating a case library and the solution is compared with results provided by an optimal power flow and a genetic based algorithm. The main advantage of the propose model is the unified treatment of the voltage profile and the reactive dispatch without the need of a two-step algorithm. The proposed controller is suitable for online real-time applications and it is flexible when dealing with problems that present a complex analytical formulation. [ABSTRACT FROM AUTHOR]

This paper shows the exergy analysis applied to the gasification process of residual biomass with the purpose of obtaining useful energy. A model for the biomass gasification based on chemical equilibrium of the reactions is proposed. The model allows predicting the syngas composition as a function of temperature, pressure and ultimate analysis of palm oil and grapevine pruning waste (determining hydrogen, oxygen, carbon and nitrogen). It was found that the carbon monoxide and hydrogen concentration significantly increase at high pressure and temperature independently of the gasifying agent. Furthermore, it was also noticed that the exergy efficiency increases as temperature increases, and decreases as the relative fuel/air ratio increases. [ABSTRACT FROM AUTHOR]

This paper presents an extension of AspectZ to model the requirements of software that manages a system of electronic health records in Chile: SYSFIC 1.0. AspectZ is an aspect-oriented language that preserves the basic characteristics of language Z and that aims to encapsulate cross-cutting concerns of a system into separate and independent entities. The application includes the use of Unified Modeling Language (UML) diagrams and a formal modeling of the system using AspectZ. The main features of the aspect-oriented modeling paradigm, such as the separation of concerns and the reduction and elimination of scattered and tangled code, are discussed. The results of this study show that the combination of aspect-oriented modeling and a formal method of software development allow obtaining more reliable solutions for critical information systems such as SYSFIC. [ABSTRACT FROM AUTHOR]

In this paper, the instantaneous power theory of the Institute of Electrical and Electronics Engineers (IEEE, Std. 1459 of 2010) used for single-phase electric systems is expanded to threephase electric systems. A general instantaneous power expression is obtained through instantaneous voltages and currents. This expression is useful to explain the phenomena in electrical systems. This expression is also verified through experimental tests relating power flow and its causes. There are numerous instantaneous power expression reported in the literature, but these expressions do not relate physically and mathematically the electrical phenomena and its causes. For this reason, it is proposed to use the instantaneous power theory to explain physical phenomena in electrical systems contributing with a power theory that can be simultaneity used for measuring or monitoring to revenue purposes, for evaluating the power quality, for designing active filters, and for detecting sources of harmonic distortion. [ABSTRACT FROM AUTHOR]

In this paper, a character reference model, based on its perception and reasoning, with the objective of achieving visual realism in an Intelligent Virtual Environment (IVE) is proposed. The necessary steps for obtaining the model are: i) to identify the characteristics of the objects and of the virtual character of the IVE; ii) design of the IVE model; iii) specification of the Artificial Intelligence technique (AI); iv) defining the physical level and semantic system for the integration of the character with the environment; v) validation of the proposed model in a prototype; and vi) evaluation of the results. The proposed model allows generating an appropriate dynamics between the character en the elements of the virtual environment, which is required in several applications. [ABSTRACT FROM AUTHOR]

The concept of Carbon Footprint, its origin, its relation with greenhouse gases and the methods to quantify it are presented and analyzed. The so-called greenhouse effect causes that the energy that reaches the earth at a certain rate is returned to a slower rate, increasing the temperature of the earth surface. Additionally, it is nowadays accepted that this effect is produced by some gases that are naturally emitted or produced by human actions. The Carbon Footprint is considered to be one of the most important tools for quantifying greenhouse emissions and in a general form it represents the quantity of gases emitted to the atmosphere and that is produced by human activities, and by goods and service consumption. Since there is no consensus about the definition of Carbon Footprint or the forms of quantifying it, this first part of the paper series analyzes the main concept and the main present views on the Carbon Footprint. [ABSTRACT FROM AUTHOR]

This paper determines the tractor stock and aggregate adoption growth of agricultural tractors in Chile. A logistic model was applied to determine the adoption growth and the adoption speed of agricultural tractors. Model parameters were determined by a non-linear algorithm. The tractor stock balance and the tractorization curve were used to estimate variation rate between t and t-1. This variation was associated with the introduction of tractors and those units removed from the stock. The logistic model showed a significant adjustment level and allowed estimating the rate of adoption and the adoption saturation level. It is concluded that the methodology can be applied to study technological adoption in other regions and other countries. [ABSTRACT FROM AUTHOR]

In this paper, a review for threshold-based visual cryptography (VC), a visual representation of the secret sharing scheme is presented. The VC has potential applications in the electronic banking system, as well as in personal identification systems. En la VC a binary image such as letters, logotypes or halftone images are shared among a group of participants using a set of images, so called shares. Until now several VC schemes, such as threshold-based VC, the general access VC and the extended VC, have been proposed. The conditions that must be satisfied for a correct recovery of the secret message, as well as the most relevant security issues of this scheme are also analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the design of air-heaters made of bimetallic thermosyphons to recover the energy contained in the flue gases of industrial boilers. A computer program written in Visual Basic that performs the thermal calculation of different compact air-heaters was used. With the program it was possible to obtain several configurations of air-heaters that satisfy the operating conditions of a Cleaver-Brooks CB 250 boiler. A compact air-heater was designed with dimensions of only the fifth part of the boiler dimension. With this design efficiency increase of 5% was obtained. [ABSTRACT FROM AUTHOR]

In this paper the computational implementation of a model for the administrator of industrial maintenance, the person who must decide about the priority in which the productive equipments in a company should be replaced. The system takes into account the level of importance in the evolution of new products that the company wants to produce and to satisfy the ones already in the market. The program gives priority to the replacement of equipment based on its impact on productivity, the level of adaptability with the evolution of the product and the replacement cost of the new equipment. All of the data introduced on the spreadsheet reflect the appreciation that of the piece of equipment has on its surrounding. The results are analyzed and graphically presented. [ABSTRACT FROM AUTHOR]

This paper presents a proposal for using the latent heat of the steam condensed in an economizer used to preheat the feeding water to the steam generator, with the aim of increasing the efficiency of thermal power plants. A novel methodology applied to power plants producing over 350 MW power plants and that use natural gas is developed. Also, a detailed study of the different alternatives proposed is presented and their direct effects on the economic feasibility have been evaluated. Increases up to 0.6 % in the global efficiency are obtained, besides short return investment periods, depending on the annual effective working hours of the power plant. [ABSTRACT FROM AUTHOR]

The objective of this paper is to show an alternative for the coexistence with the salinity problem of irrigation water caused by underground dams. The quality of irrigation water is analyzed by comparing the vegetative growth of Capim Vetiver, Sempre Verde, Cana-de-Açúcar, Capim Elefante cv. Napier and Capim Elefante cv. Mercker, upstream and downstream of the underground dam located in Ibicuitinga, Ceará state in Brazil. The analysis of groundwater samples upstream and downstream of the dam have shown that both have high salinity for irrigation, recommending the use of halophytes crops. The study includes an analysis of variance for height growth variable and the Tukey test was applied. From this test it was verified that among the gramineous plants tested, only the Capim Elefante cv. Mercker was found statistically different. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study on the formation of NOx in a 350 MW steam generator that burns fuel oil. The objective of this work was to determine the NOx formation applying two different constructions of recirculation gases. The first construction has the introduction of recirculation gases in the bottom of the furnace and the second one involves injection of recirculation gases in the hot air duct. In both cases, the study was developed at different thermal loads, maintaining constant the fractions of recirculation gases for each thermal load. The results show that the introduction of recirculation gases in the hot air duct reduces NOx formation by 58 % compared to those obtained with the traditional method of injection of gases in the bottom of the furnace. [ABSTRACT FROM AUTHOR]

This paper proposes a modification to the traditional process for obtaining boric acid with the addition of acid leaching split, to get a highly soluble product, as sodium pentaborate. In this way the mineral can be dissolved without heating, decreasing the amount of leaching reagent, thus saving energy. The pH of the clarified liquid is decreased leading to the precipitation of boric acid. The gangue runs out at different stages of precipitation and filtration, with its successive washes, improving process performance. The produced boric acid has characteristics, such as texture and purity, comparable with that obtained by traditional processes. [ABSTRACT FROM AUTHOR]

The aim of the work presented in this paper was to reduce makespan time and idle time, and to increase machine utilization, in Job Shop-Open Shop environment, using a new methodology based on evolutionary algorithms. The study was done in an enterprise of the metal-mechanics sector. The proposed methodology is easy to implement and apply and the results are highly consistent, as shown by a variance analysis. The methodology allows reducing the total processing time by 33% and idle time by 51% with 99% approximation with respect to the optimum solution. [ABSTRACT FROM AUTHOR]

The main objective of the work presented in this paper is the evaluation of different methods for the extraction of almond oil (Anacardium occidentale L) and the characterization of its physicochemical properties. The procedure involves subjecting the sample to mechanical extraction process, or pressing and solvent extraction using two methods, immersion and immersion-percolation. The most efficient method was the immersion-percolation using n-hexane as solvent. The yield obtained is (97.78 ± 1.12)%. The fatty acid analysis by HPLC revealed high content of oleic acid (61.36%). From these results solvent extraction is recommended for the soap industry, for cosmetics and extraction by pressing in the food industry. [ABSTRACT FROM AUTHOR]

In this paper, the analysis, statistical characterization and modeling of a video on demand (VoD) service running on a cable network HFC (Hybrid Fiber Coaxial) is presented. Audio and video services produce a high consumption of resources on the network infrastructure. Thus, it is necessary to perform detailed studies that allow evaluating the impact of implementing these services and their effect on other services running on the same network. The audio and video service uses the RTMP protocol for multimedia traffic transmission between clients and server. With the objective of evaluating the service performance on cable network, several scenarios with different configurations of the media access control protocol in HFC networks have been analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the process used for the adaptation of an e-learning application to a t-learning application from the point of view of graphic interfaces, including usability aspects and technical restrictions of interactive digital television. The process was evaluated through a study case in which an application of e-learning was adapted to a digital television environment. With the proposed process a guide with defined activities has been created which allow to systematically adapting the applications of t-learning in the TDi context. This implies that the contents of t-learning can be enriched in a quicker manner. [ABSTRACT FROM AUTHOR]

This paper presents a system for detecting angular position of targets, using feature extraction techniques in digital imaging and artificial neural networks. Military ships images graphically generated by three-dimensional solid modeling software are used. Several tests using artificial neural networks applied to the set of geometric features were performed. The results show the important contribution of recognition algorithms in determining the ship angular position, regardless of their distance from the observer. The results encourage future applications for tracking targets using infrared images. [ABSTRACT FROM AUTHOR]

This paper presents design and construction of an experimental test to determine the thermal resistance of a hollow concrete blocks wall, according to the international standard known as guarded hot plate. The construction procedure and implementation of the device are described, reproducing operations conditions for buildings located in warm dry climate, and the thermal resistance was experimentally and numerically determined. The results were found by applying controlled temperature differences on both sides of the wall between heating and cooling temperature zones, in steady state conditions. Experimental and numerical results show variations in the value of thermal resistance, ranging from 0.15 to 0.19 °C m2/W. Values of the thermal resistance were fitted to an empirical expression as function of the temperature difference between the walls and the average temperature of the wall. [ABSTRACT FROM AUTHOR]

The objective of this paper was the proposal of a business process model for the management of patents resulting from ideas or projects developed in universities. For the design of the model, several actions were developed: surveys, interviews, and analysis of web sites, with the aim of determining the set of activities followed in other institutions from the original idea until patent exploitation. This information and its analysis were done using the process modelling by regulation, later translated into a model in BPMN (Business Process Modeling Notation). It is shown that the proposed model facilitates the management of patents in universities. [ABSTRACT FROM AUTHOR]

The effect of certain simplifications in calculations of alcoholic distillation columns, such as to consider ethanol and water as the only components and to neglect heat losses is analyzed. The effect of reducing the number of components in the wine, from nine to the binary ethanol+water, over the enthalpy of the streams is discussed. The analysis was done from a nine components solution to the binary system ethanol-water. Three models for estimating the required properties were used showing that results are not significantly affected. The effects of heat losses by convection and radiation were estimated on both rectifying and purifying columns for insulated and non insulated cases were evaluated. The paper shows that the simplifications introduced to the HYSYS simulator are correct. [ABSTRACT FROM AUTHOR]

This paper presents the design to get a beam-to-column connection stiffer using steel glued-in rods. Some parametric finite element models, which could comprise all the possibilities, were developed to carry out the work. From the analysis of the results, it can be observed the need for the glued-in rods, specially the exterior ones, when it is necessary that the joint resists great loads and moments without overcome the yielding strength limits of the timber. The transverse glued-in rods are necessary to resist the tangential and the perpendicular to the grain stresses in the border between the beam and the column. The interior glued-in rods seem to have a non important role, because the greater part of the compression forces in this area are transmitted by contact between the column and beam surfaces. [ABSTRACT FROM AUTHOR]

This paper presents the use of the finite elements method to study the flanking transmission through the use of the vibration reduction index, for the case of constructive solutions that use floating floors. On one side, the insertion of elastic interlayer in new building solutions is now a very common practice. On the other side, the test procedures for the acoustic study of this kind of sets (concrete floor with elastic interlayer) are very laborious and the existing empirical equations do not match reality in many cases. For this reason, the study of the problem using finite elements would allows giving numerical solution to a wide range of different constructive solutions and numerical prediction for the acoustical isolation could be improved. [ABSTRACT FROM AUTHOR]

The author presents the conference that van der Waals delivered when he received the Nobel Prize for Physics in 1910. This work is a contribution to the several commemorating activities that are being organized around the world to celebrate the 100 years since van der Waals was awarded the maximum prize. The conference summarizes some of the main achievements and in particular the equation of state, the principle of corresponding states and the theory of mixtures. These pioneering ideas of van der Waals have influenced several areas of physics and thermodynamics but in particular these three concepts, which motivated his merited Nobel Prize. The paper concludes that even after a hundred years since the Nobel and more than 125 years since the doctoral thesis, and despite of many other extraordinary advances in physics and thermodynamics, the concepts of van der Waals continue more valid than ever. [ABSTRACT FROM AUTHOR]

This paper presents a method to solve the ambipolar diffusion equation for modeling and simulating the PiN diode in silicon carbide, using an empirical approximation. Through this methodology a set of differential equations that simulate the main physical phenomena associated to the power semiconductor device are obtained. The equations, implemented in Pspice, model in a more actual form the charges behaviour in the N- region of a PiN diode in silicon carbide for the static and dynamic phases. For the verification and validation of the model, the simulation results were compared with experimental data reported in the literature, obtaining accurate results for application in power electronic. [ABSTRACT FROM AUTHOR]

This paper presents a multiobjective analysis including variables of the environment of the energy system which is conditioned by the use of solid fuels, for this reason the analysis includes the external characteristics of the resource (fuel) of residue (ash) and the product (electricity/steam). The energy system used is Termocesar, a Colombian process for generating electricity from carbon. Three functions named thermoeconomic objective function, technology objective function and environmental objective function, are analyzed to establish the best location of the energy The genetic algorithm method is used for the optimization of the system. The results were analyzed for nine combinations of weights and show that for most of the cases the optimum includes coals from the Department of Cesar in Colombia. [ABSTRACT FROM AUTHOR]

In this paper a theoretical analysis of magnetic three-phase induction machine is presented, including an identification parameter from its equivalent circuit. The approach has become an outstanding model for the mechanical part in the same equivalent circuit, and the machine as a whole. The equations obtained have been raised as state variables. Then, the differential equations can be expressed in function of the first derivative, obtaining a unified method for the simulation and numerical analysis. Through programs developed in C++, a complete sensitivity analysis for the steady state and dynamic models was developed. This allowed to observe and to study the influence and relationship between these parameters. [ABSTRACT FROM AUTHOR]

In this paper the finite element method is applied to the analysis of a three-phase magnetic induction motor squirrel-cage. Different geometries have been applied in the design of the rotor. These geometric variations of the rotor create an electromagnetic profile for each type of geometry. To study the rotor motion, a frequency analysis of the model has been done. The identifying parameters deduced from the finite element method, are adjusted by evolutionary genetic algorithms. Thus, the parameters in the circuit model were identified for each geometry under consideration. A check of the torque was done to validate the model, verifying the accuracy of the method. [ABSTRACT FROM AUTHOR]

This paper presents a study that compares operative results for three technological alternatives to produce electricity and compress gas in offshore crude oil processing facilities to be installed in Mexico. The comparison of alternatives is made based on system reliability estimations by using the "reliability block diagram" method. The fundamental concepts of the systems reliability theory are pointed out, and the reliability model is defined as a parallel arrangement with redundancy in passive reserve and without maintenance for any component. Likewise, the alternatives, and the analyzed operative scenarios are described, including the block diagrams and reliability results for each option. The results of the study show that using electrical motors to compress gas and internal combustion engines to produce electricity is more reliable than using gas turbines. [ABSTRACT FROM AUTHOR]

This paper presents a heat transfers study in a hollow concrete blocks wall to know its thermal resistance. A one dimensional steady-state model was developed, which includes conduction, radiation and convection. The model was solved numerically using Gauss-Seidel iterative method. The simulation was run hourly for two days in climatic extreme conditions. The thermal resistance average value obtained was 0.18 °Cm²/W with variations of 2.3% to 23%. The average contribution to the total heat flow for every transfer mechanism is: 25%, 19% and 56% by conduction, convection and radiation respectively. The wall presents thermal resistance values which tend to decrease with the increase of temperature differential. This aspect presents disadvantages for thermal behavior in warm climate and the radiation into the block cavity is the most important heat transfer process across the wall. [ABSTRACT FROM AUTHOR]

In this paper is presented a validated and implemented model in Excel, to evaluate the state of maturity, understanding for that the organization is well conditioned to deal with their projects, based on aspects of commitment to change, organizational culture, communication inside and outside the department, use of tools for project management and conflict resolution. The results are given in a graphic-narrative form which is a starting point to implement strategies for innovation in maintenance management process. One of the principal points of the methodology is the use of a questionnaire, elaborated under the MCDA procedure, designed to characterize the aspects named in the form of quantifiable variables, that is, assimilate a value or a well-defined concept for each state in which the variables that modeling the system under study may arise. [ABSTRACT FROM AUTHOR]

This paper uses the discretization estimator error Z2, proposed Zienckiewz and Zhu, for implementing the refinement by subdivision in hexahedrons elements. Obtaining improved tension field is based on techniques of smoothing tensions by zones, developing three procedures for evaluating the error. The procedures developed in this work were applied to two problems with known solution, in order to evaluate and define the characteristics of each proposed technique. In was observed that in the problem with smooth solution the technique that considers the presence of fictitious nodes and reduced integration could be used. However, in the problem with singularities it is better to consider the nodes with full integration for error estimation. [ABSTRACT FROM AUTHOR]

The design and evaluation of several configurations of evaporative cooling systems for air conditioning of a dwelling for low-income sectors in Mexicali, Mexico using simulation with TRNSYS 16.A is presented in this paper. The configurations studied include direct as well as indirect evaporative cooling with heat exchange and also systems with solid desiccant. The main rating parameters to classify the different configurations are the internal comfort conditions, the efficiency and the number of required equipments. The results show that the best configuration is one that includes a heat exchanger that pre-cools the air inlet stream with a cooling stream delivered by air coming from the dwell, but there is a small fraction of the time during the day that comfort is not met. If thermal comfort is to be met during the whole day, solid desiccant systems are the best choice. [ABSTRACT FROM AUTHOR]

This paper presents the properties of high temperature superconductor (HTS) materials in the construction of electrical machines. A disc type configuration synchronous generator with high specific power for future wind power applications is described. The generator is excited by means blocks of HTS ceramic materials. The mechanism to trap the magnetic flux in HTS blocks is explained. To decrease the weight of the generator on the top of the tower, the cryogenic system used consists of a liquid nitrogen storage container located on the ground to reduce weight on the tower. A flux plot per two poles of the machine calculated using the finite element method is presented and the flux density distribution in the air gap of the superconducting disc generator is also displayed. A high efficiency wind park with this type of generators is proposed. [ABSTRACT FROM AUTHOR]

This paper deals with the application of six sigma methodology (DMAIC) and Taguchi methods to solve the problem of low resistance of the pulling test of a light emitting diode (LED), which is used in the assembly of cellular telephones in a northwest Mexican electronic company. After finishing this project a significant improvement was achieved that made possible to increase process capability from 0.56 to 1.45 and the impact in cost reduction only by the elimination of waste was of 130 thousand US dollars in savings per year. This achievement did not require additional investment, it was only necessary to control each of the most important factors in the process. [ABSTRACT FROM AUTHOR]

In this paper a study on the impact of Foreign Direct Investment on Economic Growth in 14 Latin American countries is presented. With this purpose the relationship of Foreign Direct Investment per capita with Gross Domestic Production per capita variation (as a proxy for Economic Growth) and Private Capital per capita variation during the period 1996-2003 were analyzed. A model with two simultaneous equations that are solved using fixed-effects panel for both analysis of countries and the study of the time effect. The results allows concluding that for those countries studied the Foreign Direct Investment boosts both the Private Capital per capita accumulation and the Income per capita growth. The Institutional Quality, mainly that related to private property rights protection and individual freedom, are determining factors for Growth. It was finally found that Public Investment also boosts Growth and the countries considered in the analysis show conditional convergence, which is consistent with the mainstream literature. [ABSTRACT FROM AUTHOR]

This paper describes the development of a novel synthesis of mesoporous silica based on a twostep process, in acidic media (pH = 2), using renewable raw materials. The first stage was the formation of stable hybrid micelles, product of the interaction between the porogen and silicates, and the second was the polycondensation of silicates to produce silica. Two sources of silicon were used: tetraethylortosilicate (TEOS) and sodium metasilicate (MSiNa). Glycerol monostearate was used as oleochemical porogen and sodium fluoride was used as initiator for the reaction of condensation of silica. The silica obtained with the best textural properties have interesting surface characteristics for potential applications in heterogeneous catalysis, with BET surface area of 727.4 m2 / g, total volume of pores of 0.50 cm3/g and pore size distribution of about 46.2 Å. [ABSTRACT FROM AUTHOR]