Genome-wide association mapping for root traits in a panel of rice accessions from Vietnam

Background: Despite recent sequencing efforts, local genetic resources remain underexploited, even though they carry alleles that can bring agronomic benefits. Taking advantage of the recent genotyping with 22,000 single-nucleotide polymorphism markers of a core collection of 180 Vietnamese rice varieties originating from provinces from North to South Vietnam and from different agrosystems characterized by contrasted water regimes, we have performed a genome-wide association study for different root parameters. Roots contribute to water stress avoidance and are a still underexploited target for breeding purpose due to the difficulty to observe them. Results: The panel of 180 rice varieties was phenotyped under greenhouse conditions for several root traits in an experimental design with 3 replicates. The phenotyping system consisted of long plastic bags that were filled with sand and supplemented with fertilizer. Root length, root mass in different layers, root thickness, and the number of crown roots, as well as several derived root parameters and shoot traits, were recorded. The results were submitted to association mapping using a mixed model involving structure and kinship to enable the identification of significant associations. The analyses were conducted successively on the whole panel and on its indica (115 accessions) and japonica (64 accessions) subcomponents. The two associations with the highest significance were for root thickness on chromosome 2 and for crown root number on chromosome 11. No common associations were detected between the indica and japonica subpanels, probably because of the polymorphism repartition between the subspecies. Based on orthology with Arabidopsis, the possible candidate genes underlying the quantitative trait loci are reviewed. Conclusions: Some of the major quantitative trait loci we detected through this genome-wide association study contain promising candidate genes encoding regulatory elements of known key regulators of root formation and development

Genome-wide association study of a panel of vietnamese rice landraces reveals new QTLs for tolerance to water deficit during the vegetative phase

Background: Drought tolerance is a major challenge in breeding rice for unfavorable environments. In this study, we used a panel of 180 Vietnamese rice landraces genotyped with 21,623 single-nucleotide polymorphism markers to perform a genome-wide association study (GWAS) for different drought response and recovery traits during the vegetative stage. These landraces originate from different geographical locations and are adapted to different agrosystems characterized by contrasted water regimes. Vietnamese landraces are often underrepresented in international panels used for GWAS, but they can contain original genetic determinants related to drought resistance. Results: The panel of 180 rice varieties was phenotyped under greenhouse conditions for several drought-related traits in an experimental design with 3 replicates. Plants were grown in pots for 4 weeks and drought-stressed by stopping irrigation for an additional 4 weeks. Drought sensitivity scores and leaf relative water content were measured throughout the drought stress. The recovery capacity was measured 2 weeks after plant rewatering. Several QTLs associated with these drought tolerance traits were identified by GWAS using a mixed model with control of structure and kinship. The number of detected QTLs consisted of 14 for leaf relative water content, 9 for slope of relative water content, 12 for drought sensitivity score, 3 for recovery ability and 1 for relative crop growth rate. This set of 39 QTLs actually corresponded to a total of 17 different QTLs because 9 were simultaneously associated with two or more traits, which indicates that these common loci may have pleiotropic effects on drought-related traits. No QTL was found in association with the same traits in both the indica and japonica subpanels. The possible candidate genes underlying the quantitative trait loci are reviewed. Conclusions: Some of the identified QTLs contain promising candidate genes with a function related to drought tolerance by osmotic stress adjustment

Is the Broad-Line Region Clumped or Smooth? Constraints from the H alpha Profile in NGC 4395, the Least Luminous Seyfert 1 Galaxy

The origin and configuration of the gas which emits broad lines in Type I active galactic nuclei is not established yet. The lack of small-scale structure in the broad emission-line profiles is consistent with a smooth gas flow, or a clumped flow with many small clouds. An attractive possibility for the origin of many small clouds is the atmospheres of bloated stars, an origin which also provides a natural mechanism for the cloud confinement. Earlier studies of the broad-line profiles have already put strong lower limits on the minimum number of such stars, but these limits are sensitive to the assumed width of the lines produced by each cloud. Here we revisit this problem using high-resolution Keck spectra of the H alpha line in NGC 4395, which has the smallest known broad-line region (~10^14 cm). Only a handful of the required bloated stars (each having r~10^14 cm) could fit into the broad-line region of NGC 4395, yet the observed smoothness of the H alpha line implies a lower limit of ~10^4-10^5 on the number of discrete clouds. This rules out conclusively the bloated-stars scenario, regardless of any plausible line-broadening mechanisms. The upper limit on the size of the clouds is ~10^12 cm, which is comparable to the size implied by photoionization models. This strongly suggests that gas in the broad-line region is structured as a smooth rather than a clumped flow, most likely in a rotationally dominated thick disk-like configuration. However, it remains to be clarified why such a smooth, gravity-dominated flow generates double-peaked emission lines only in a small fraction of active galactic nuclei.Comment: 12 pages, including 3 figures, accepted for publication in The Astrophysical Journa

El Dilema de la Escala Productiva frente a Ciclos de Abundancia: La Pesca Industrial en Chile

A menudo la escala productiva de diversas pesquerías en el mundo muestra escasa flexibilidad frente a caídas en la abundancia de la pesca, lo que en ocasiones ha generado situaciones de colapso pesquero. Aquí estudiamos las dos pesquerías con mayor volumen de desembarques en Chile y que se caracterizan por enfrentar variabilidad en su abundancia. Analizamos aspectos productivos que afectan los incentivos para ajustar a la baja el esfuerzo pesquero. Para ello estimamos funciones de captura para las flotas industriales que operan en cada pesquería usando datos de panel. Los resultados plantean dos áreas de conclusión. Primero, evidencia que avala la relevancia empírica de tecnologías de captura Translog. Esto contradice una práctica habitual en modelos bioeconómicos, cual es considerar elasticidades captura-insumos constantes e independientes de la escala de producción. Segundo, identificamos un conjunto de efectos productivos que debilitan los incentivos para ajustar a la baja el esfuerzo pesquero: economías de escala en el uso de insumos variables, economías externas asociadas al esfuerzo agregado de búsqueda de cardúmenes, y rendimientos de pesca sensibles a cambios en la abundancia, pero donde la fuerza de este efecto disminuye al caer la abundancia.

Characterization of the K2-18 multi-planetary system with HARPS: A habitable zone super-Earth and discovery of a second, warm super-Earth on a non-coplanar orbit

The bright M dwarf K2-18 at 34 pc is known to host a transiting super-Earth-sized planet orbiting within the star's habitable zone; K2-18b. Given the superlative nature of this system for studying an exoplanetary atmosphere receiving similar levels of insolation as the Earth, we aim to characterize the planet's mass which is required to interpret atmospheric properties and infer the planet's bulk composition. We obtain precision radial velocity measurements with the HARPS spectrograph and couple those measurements with the K2 photometry to jointly model the observed radial velocity variation with planetary signals and a radial velocity jitter model based on Gaussian process regression. We measure the mass of K2-18b to be $8.0 \pm 1.9$ M$_{\oplus}$ with a bulk density of $3.7 \pm 0.9$ g/cm$^3$ which may correspond to a predominantly rocky planet with a significant gaseous envelope or an ocean planet with a water mass fraction $\gtrsim 50$%. We also find strong evidence for a second, warm super-Earth K2-18c at $\sim 9$ days with a semi-major axis 2.4 times smaller than the transiting K2-18b. After re-analyzing the available light curves of K2-18 we conclude that K2-18c is not detected in transit and therefore likely has an orbit that is non-coplanar with K2-18b. A suite of dynamical integrations with varying simulated orbital eccentricities of the two planets are used to further constrain each planet's eccentricity posterior from which we measure $e_b < 0.43$ and $e_c < 0.47$ at 99% confidence. The discovery of the inner planet K2-18c further emphasizes the prevalence of multi-planet systems around M dwarfs. The characterization of the density of K2-18b reveals that the planet likely has a thick gaseous envelope which along with its proximity to the Solar system makes the K2-18 planetary system an interesting target for the atmospheric study of an exoplanet receiving Earth-like insolation.Comment: 13 pages, 8 figures including 4 interactive figures best viewed in Adobe Acrobat. Submitted to Astronomy & Astrophysics. Comments welcom

Diseño e implementación de un sistema electrónico de alarma e inmovilización vehicular controlado por un teléfono inteligente con comunicación Bluetooth

This project of Electrical-Electronic Engineering in Telecommunications consists in the implementation of an electronic alarm and vehicle immobilizer technologically innovative because it employs Bluetooth technology and the use of smartphone. The purpose of this work lies in the replacement of the radio frequency device "traditional Remote Control" for an application installed on the smartphone of the vehicle´s owner. This thesis was developed in three segments. The creation of an intuitive and invulnerable smartphone application; the establishing of an autonomous and indecipherable Bluetooth connection between the smartphone and the microcontroller; and, the implementation of a microcontroller and an electronic circuit that is multitasking, low power consuming, compact and resistant to climatic factors. Once completed the process described above, the results are integrated to check if the objectives set at the beginning of this research were achieved with satisfaction. The hardware and software used in this thesis were: Microsoft Visual Studio 2008 IDE, the Samsung i637 smartphone with Windows Mobile 6.5, the RN-41 Bluetooth module, the ATMEGA8 microcontroller, the compiler Bascom, Proteus simulator and a professional electronic circuit.Este proyecto de Ingeniería Eléctrica Electrónica en Telecomunicaciones consiste en la implementación de un sistema electrónico de alarma e inmovilización vehicular tecnológicamente innovador ya que emplea tecnología Bluetooth y el uso de smartphone. El propósito de este trabajo reside en la sustitución del dispositivo de radiofrecuencia “Control Remoto tradicional” por una aplicación instalada en el smartphone del dueño del vehículo. Esta tesis se desarrolló en tres segmentos. La creación de una aplicación smartphone intuitiva e invulnerable; el establecimiento de una conexión Bluetooth autónoma e indescifrable entre el smartphone y el microcontrolador; y, la implementación de un microcontrolador y un circuito electrónico que sea multitarea, de bajo consumo eléctrico, compacto y resistente a factores climáticos. Una vez concluido el proceso anteriormente descrito, los resultados se integran para verificar si los objetivos planteados al inicio de esta investigación fueron alcanzados con satisfacción. El hardware y software utilizados en esta tesis fueron: el IDE Microsoft Visual Studio 2008, el smartphone Samsung i637 con Windows Mobile 6.5, el módulo Bluetooth RN-41, el microcontrolador ATMEGA8, el compilador Bascom, el simulador Proteus y un circuito electrónico profesional

Active management in mutual funds with concentrated benchmarks: A major dilemma to fulfill the EU directive on portfolio concentration limits.

his doctoral thesis is focused on the increasing importance of mutual funds as saving vehicles for the finances of individuals in the economies of developed countries over the last half of the twentieth century. Among them, the equity funds that take the form of open-end funds like mutual funds are becoming one of the most relevant instruments. Mutual funds collect money from investors and invest it in stocks, bonds, other funds, and so on, and their performance depends on the mix of the allocated securities. Its main objectives were to contribute to the topic of the Active Share (AS) as applied to mutual funds in Eurozone countries. This investigation was mainly motivated by the need to analyse how both the level of concentration of the benchmarks and the level of concentration of the mutual fund industries in the Eurozone affect active management. Due to the scarce number of studies focused on this topic in Europe our results have relevant implications to investors, market supervisors, and policymakers. In Chapter 1, we analysed how article 52 in Directive 2009/65/EC (UCITS IV) on risk of portfolio diversification could distort the accuracy of AS due to the higher level of concentration in Eurozone domestic benchmarks. In this chapter, we were able to identify truly active management in Eurozone mutual funds. Thus, we developed an algorithm to capture the spurious AS (sAS), which is defined as the minimum AS, that is not a consequence of active decisions made by equity fund managers. The results provide evidence that the Directive negatively influences the accuracy of the AS shown for managers who work with very concentrated domestic Eurozone benchmarks such as the PSI 20 (Portugal), ATX 20 (Austria), and IBEX 35 (Spain). In contrast, the evidence from the sAS for the least concentrated domestic Eurozone benchmarks shows that AS reported by managers who work in France, Germany, and Finland are much more accurate. Hence, these results prove that direct AS comparisons in the Eurozone are not feasible and lead us to obtain three AS thresholds per domestic equity benchmark, which are the minimum values of AS needed to confirm that domestic equity funds are significantly active at 90%, 95%, and 99% confidence levels.We also analysed the level of active management in the domestic equity funds registered in each Eurozone country. Our findings also show that the high concentration level and the heterogeneity present in the domestic equity funds in the Eurozone prevent the direct comparability of the AS. Therefore, we had to consider the level of AS over the spurious level and the characteristics of each market that produces significant and different styles of active management. For that, we formulated an actual active share (aAS) that considered the level of concentration in the domestic equity funds of the Eurozone markets and the limits of the portfolio concentration on European regulation. We define aAS as the difference between the monthly AS obtained for each domestic equity fund minus its monthly AS threshold obtained previously at 90%, 95%, and 99% confidence levels. Focusing on the most relevant mutual fund industries in the Eurozone countries, we find that France is the most active domestic equity fund market. Spanish and Italian markets also show high levels of actual active management despite the large concentration in their domestic benchmarks. Conversely, domestic equity funds registered in Germany show lower levels of active management. Our research results support the hypothesis that aAS corrects the potential bias in the original AS caused by both the domestic benchmark concentration and the EU portfolio diversification rules.In summary, our study is the first to evaluate the consequences of both the assorted characteristics of domestic Eurozone benchmarks and the European regulation that prevents portfolio concentration (UCITS IV) in the appropriate estimation of AS. Furthermore, our study identifies truly active management in domestic equity funds in the Eurozone markets. This chapter has important implications for policymakers and practitioners of the domestic equity funds in the Eurozone. In the strongly regulated European markets, our unbiased approach allows both investors and market supervisors to identify the accurate levels of active management of each industry after considering both the regulation of portfolio diversification and the concentrated domestic equity benchmarks. Market supervisors will have a better picture of the active management map to develop appropriate regulations for the mutual fund industry. In addition, our approach should help practitioners and investors to effectively find out the level of active management of domestic equity funds and therefore provide information for fund management companies to replace actual performing managers. Further, our results should help to reduce the opacity in the management fees that funds charge by providing accurate measures of active management. In Chapter 2, we analysed how some market and fund characteristics play a crucial role in explaining the portfolio concentration default on Directive 2009/65/EC (UCITS IV). This chapter should help market supervisors to improve the monitoring process of defaults by domestic equity funds in the Eurozone mutual fund industries. On the one hand, the origin of UCITS directives was considered the beginning towards market protection and increased transparency in the Eurozone. On the other hand, the structure of mutual funds allows retail investors to access sophisticated active strategies that comply with liquidity and transparency restrictions protected by regulatory oversight. Their rules are based on a certain degree of portfolio diversification with the goal of reducing their vulnerability to portfolio risks. This chapter is the first to analyse how concentrated strategies could lead to non-compliance with article 52 in UCITS IV. First, we analysed several market characteristics that may influence the probability of a fund manager failing to meet the portfolio concentration limits. Using a logic panel data model (fixed effects), we estimated the probability of incurring defaults. Our findings provide evidence that should lead market supervisors to pay attention to concentrated fund industries with concentrated domestic benchmarks to prevent defaults on Eurozone concentration limit. The level of concentration of the domestic equity benchmarks would make the defaults almost twice as likely to occur. The level of concentration of the domestic fund industry also has positive and significant effects on the likelihood of incurring defaults. That is, defaults are approximately 12% to 17% more likely to occur when the level of concentration in the domestic fund industry increases. This evidence is consistent with the findings in the literature that link competition with active management strategies such as concentrated portfolios (see Dyck et al., 2013). Second, in the same line of Chapter 1, we analysed several funds characteristics that may influence the probability of a fund manager failing to meet the portfolio concentration limits. In Eurozone markets, market supervisors should especially monitor the most experienced funds that are solo-managed to prevent portfolio weights over the 10% limit. This finding is in accordance with Goldman et al., (2016) who shows that individual managers have much more concentrated portfolios than management teams. The fund’s age has a positive and significant influence on the likelihood of defaults. That is, the probability of incurring defaults is approximately 18% to 26% higher among older funds. Thus, this evidence is in accordance with the literature that links older funds with higher levels of idiosyncratic risk as a consequence of having more concentrated portfolios (see Amihud and Goyenko, 2013). Further, we analysed the characteristics of those stocks that were especially subject to more concentrated strategies and, therefore, more vulnerable to mutual funds’ investment policies. For that, we applied a multinomial logic panel data model (fixed effects) and found that the weight of the stocks in their benchmarks had a positive and significant effect on default on the EU portfolio concentration limit. The results show how the probability of a stock being subject to default is approximately 8% to 25% higher when the stock weight in the domestic benchmark increases. Thus, market supervisors should monitor stocks with large weights in domestic equity benchmarks.In addition, we also find how the stocks of domestic benchmarks that have been held longer are likely to be subject to concentration defaults. That is, defaults are approximately 13% to 24% more likely to occur when choosing stocks that belong to the benchmarks during the last 24 months. Thus, this result is consistent with the literature that argues the local advantage of reducing information asymmetry problems.Thus, we find how stocks that present low volatility have a greater likelihood of being subject to non-compliance with EU portfolio concentration limits. In terms of percentages, the probability approximately lowers between 19% to 27% when stock volatility increases. This finding is in accordance with the commitment to controlled risk strategies (see Huang et al., 2011). Therefore, market supervisors should pay more attention to these stock characteristics to monitor stocks that are more frequently overweighted above EU concentration limits. In summary, this chapter is the first to both analyse and identify the determinants of domestic equity funds’ failure to comply with the portfolio concentration limits of EU Directive 2009/65/EC. Furthermore, our study also determines the characteristics of the stocks subject to these non-compliant portfolios in domestic equity funds in the Eurozone. This chapter has important implications for market supervisors and policymakers in the mutual fund industries of the Eurozone. Our approach allows market supervisors with limited resources to identify and control non-compliant domestic equity funds by monitoring only some fund-specific characteristics. The improvement of this monitoring process should contribute to the financial stability of the EU asset management industry in terms of investor protection and market transparency. That is, mutual fund unitholders should be completely certain that their money is allocated to portfolios fulfilling the concentration limits required by the EU. Our findings also show a tool to assist EU market supervisors in identifying some explanatory mechanisms for stock weights that are over the EU concentration limits. Thus, our results may help supervisors identify what kind of domestic equity funds are more inclined to default and what kind of stocks are likely overweighted by these funds. Market supervisors could especially monitor these stocks to verify that domestic equity funds are meeting the concentration limits. Market supervisors should focus their limited resources on these types of stocks held by domestic equity funds to prevent defaults in portfolio concentration. Finally, our approach could also help retail investors control their risk profiles in terms of exceeding portfolio concentration limits. This application is in line with the reinforcement of investor protection of portfolio concentration. Investors could be sure that domestic equity funds fully follow the diversification requirements and market transparency provided by the UCITS directives.Chapter 3 presents a new perspective in the analysis of active management. We introduced dynamism by proposing a new version of AS that considers how the managers deviate their portfolios in two consecutive periods. We define dynamic Active Share (dAS) as a measure to capture over time the actual level of activity by comparing the differences against the benchmark in two consecutive periods. Our measure captures not only the long and short static positions in each stock included in the benchmark but also the previous long (short) positions that have been overweighted (underweighted) in the next period. Thus, dAS allows us to divide between investment decisions driven to spread portfolio weights closer to the benchmark (i.e., decisions that lead to a lower differentiation to the benchmark) and the other which is further from the benchmark (i.e., decisions that lead to a higher differentiation). Focusing on the most relevant fund industries in the Eurozone, we analysed the predictive power of AS first. The best results were found in the Spanish industry and, with less robustness, in Germany, the Netherlands, Austria, and Belgium. France only shows this relationship in the long term when we consider the CAPM alpha; while Italy, Finland, Portugal, and Greece fail to offer significant results or even present negative relationships. These results indicate that the prediction ability of AS presents assorted results as this relation is less clear than that presented in the literature (Cremers and Petajisto, 2009) Second, we examined the influence on the prediction power for performance of AS by splitting stocks in the portfolios of our sample into benchmark and non-benchmark . The results allow us to identify how the high proportion of prediction ability for performance of AS is explained by the investment in non-benchmark stocks. Although the AS’s share of overweight or underweight benchmark stocks is really related to stock picking ability, investing in overweighted stocks may mean distortions in their performance evaluations that can lead to spurious contributions to portfolio performance.Third, we applied and analysed the predictive power of dAS. The results provided evidence that the performance of non-benchmark stocks in high AS funds did not extend to mutual funds with high dAS. Thus, this measure is less sensitive to the weight of the portfolio that is invested in non-benchmark securities that is very relevant in Eurozone countries where domestic benchmarks are highly concentrated. The main advantage of the dAS compared to the AS is that our measure provides more information and can be split according to different investment decisions. For that reason, we proposed splitting up the dAS to examine which trading decisions add value to the portfolio. Our most interesting results showed that German funds presents a robust relationship between selling investment decisions and subsequently better performance. This relationship was also found for Dutch, Austrian, and Portuguese funds but with actual limited significance. This finding is in accordance with the level of activity showed by these industries in Chapter 1.Further, we analysed the contributions to dAS that was generated by those trading decisions that might be considered as managers’ bets. These bets could be those decisions that increased holdings that were already overweighted (buy bets) or decrease those holdings that were already underweighted (sell bets). Our findings show as in Germany and in some cases in the Austrian and Portuguese industries that there is subsequent significantly better performance in buying decisions. Focusing on selling decisions, only Finnish funds show positive and strong beliefs and performance. The results for predicting performance show that those portfolios with a higher concentration of these bets offer subsequent abnormal returns as this prediction ability is even higher than the seminal AS in some of the markets in this study.Accordingly, the results shown in this chapter are an interesting addition to Cohen et al. (2010) who try to identify the trades in which the managers have more confidence. The empirical findings show that those mutual funds with trading decisions with a stronger belief from the manager (i.e., decisions that lead them to deviate even more from the benchmark) outperform the remaining funds, especially when buying decisions are considered. This evidence is consistent with Karoui and Patel (2020) who show that the benefit of AS lies in the selection decision rather than the weighting decision.In summary, Chapter 3 is the first to introduce a dynamic perspective on AS to capture managers’ activity and skill. This chapter is relevant for investors who should be interested in knowing whether their fund manager is active and whether their decisions on new investment opportunities add value to the portfolio (i.e., undervalued assets) or on the contrary, the fund manager is passive. The common argument is related to the fees because the management fees charged by these two types of funds should be different. In addition, the chapter is also relevant to regulators in order to adjust the management fees charged by management companies to the actual level of activity carried out by mutual funds. Several fields for further investigation have been identified in this dissertation. Regarding the EU Directive, an extensive test of the level of enforcement that the UCITS IV has implemented in each Eurozone country (including emerging markets) could be useful for making decisions about possible changes in the regulation. Furthermore, a complementary analysis of chapter VII in UCITS IV in terms of its appropriateness with the characteristics of each Eurozone country could allow a more complete assessment of the limits of portfolio concentration and the implementation of the protection to investors. In addition, this dissertation makes an important advance in the topic of active management to help further an analysis in other areas or regions with similar characteristics that could be relevant to the financial literature. <br /

Balanced approach for optimizing marketing networks in tourism

The article links the theory of marketing networks developed in tourism with the established Balanced Scorecard approach, offering a new balanced approach for their optimization. To this end, the formulations of the marketing network theory and their specificity in the tourism sector are briefly clarified and the Marketing Balanced Scorecard in Tourism concept is introduced as an optimization tool of the operational management of these networks.Теорія маркетингових мереж, розроблених у сфері туризму, пов'язана з підходом збалансованої системи показників, що пропонують новий метод їх оптимізації. З цією метою здійснено спробу коротко пояснити положення теорії маркетингових мереж, їх специфіку в секторі туризму. Для цього пропонується ввести поняття маркетингу збалансованої системи показників у сфері туризму як інструменту оперативного управління та оптимізації цих мереж.Теория маркетинговых сетей, разработанных в сфере туризма, увязана с подходом сбалансированной системы показателей, предлагающим новый метод их оптимизации. С этой целью предпринята попытка кратко объяснить положения теории маркетинговых сетей, их специфику в секторе туризма. Для этого предлагается ввести понятие маркетинга сбалансированной системы показателей в сфере туризма как инструмента оперативного управления и оптимизации этих сетей

Diseño de una interfaz en LabVIEW para el análisis de vibraciones mecánicas en máquinas rotativas.

In recent years, the study of mechanical vibrations has been increasing due to the enormous advantages that can be obtained with the measurement of variables related to this field, allowing significant savings in the area of maintenance and production. With the use of sensors, data acquisition cards, LabVIEW® software, guided by the international standards that regulate vibration analyzer devices, as well as simple programming, it is possible to design these meters at lower costs than commercial ones. The work consists of the use of an Arduino UNO card, which is programmed and linked as a data acquisition card, whose connection with accelerometer sensors such as the MMAl7631 and ADXL335 through LabVIEW® software. The processes and the results obtained are presented, as well as the analysis of its efficiency. The work carried out included the measurement of important variables for the timely measurement of mechanical vibrations such as rpm (revolutions per minute), mm/s (millimeter per second), phase, rps (revolutions per second), rms (rms value), etc., which allow to know the state of an alternating current rotating machine operating under load conditions.En los últimos años, el estudio de las vibraciones mecánicas ha ido en aumento debido a las enormes ventajas que se pueden obtener con la medición de las variables relativas a este campo, permitiendo ahorros significativos en el área del mantenimiento y producción. Con el uso de sensores, tarjetas de adquisición de datos, el software LabVIEW®, guiándose con las normas internacionales que regulan los dispositivos analizadores de vibraciones, así como una programación sencilla es posible diseñar estos medidores a costos más bajos que los comerciales. El trabajo consiste en la utilización de una tarjeta Arduino UNO, la cual se programa y vincula como tarjeta de adquisición de datos, cuya conexión con sensores acelerómetros como el MMA7631 y el ADXL335 mediante el software LabVIEW®. Se presentan los procesos, así como los resultados obtenidos, de igual manera el análisis de su eficiencia. Dentro del trabajo realizado se llevó a cabo la medición de variables importantes para la oportuna medición de las vibraciones mecánicas tales como los rpm (revoluciones por minuto), mm/s (milímetro sobre segundo), fase, rps (revoluciones por segundo), rms (valor eficaz), etc. los cuales permiten conocer el estado de una máquina rotativa de corriente alterna que funciona bajo condiciones de carg

Entorno de simulación basado en Marilou y MATLAB para control antibalanceo de puentes grúa

Dentro del marco del proyecto TechnoFusión se plantea el estudio de sistemas de control remoto, como el desarrollo de puentes grúas de gran tonelaje que incluyan técnicas de posicionamiento preciso y de sistemas antibalanceo. En este sentido, se ha desarrollado en este proyecto un modelo de una grúa puente sobre el que probar algoritmos de control antibalanceo. Se ha elegido la herramienta Marilou para desarrollar el modelo y la simulación de la grúa puente. Esta herramienta permite la construcción del modelo de la grúa a través de formas sencillas y dispone, además, de sensores y actuadores predefinidos que se pueden utilizar para llevar a cabo el control de la grúa y la obtención de medidas de oscilación. Para evaluar la herramienta de simulación se ha elegido un algoritmo de control antibalanceo basado en “Input Shaping” que se desarrolla, a modo de prueba, en sus modos más básicos. Este algoritmo se ha desarrollado con funciones programadas en Matlab, donde también se ha diseñado una interfaz gráfica para el control de la grúa y la visualización de las oscilaciones que se obtienen como resultado. __________________________________________________________________________________________________________Within the framework of the TechnoFusión project it is considered the study of remote control systems such as the development of large overhead cranes including anti-swinging systems and precise positioning techniques. In this regard, it has been developed in this project a model of overhead crane on which anti-swinging algorithms can be tested. For the development of the model and the simulation of the overhead crane it was chosen the tool Marilou. This tool allows the construction of the crane model through simple shapes and it also has predefined sensors and actuators that can be used to carry out the control of the crane and for the obtention of oscillation measurements. To evaluate the simulation tool, it has been chosen an anti-swinging control algorithm based on Input Shaping which has been developed, in a trial version, with the most basic functions. This algorithm has been developed with functions programmed in Matlab, where it has also been designed a graphical interface for the control of the crane and the visualization of the resulting oscillations.Ingeniería Industria