Modelling and Control of SCARA Manipulator

AbstractNowadays manipulators are getting more complex due to the development of the motor drives and the nonlinearities of the manipulator dynamics. Due to complexity of this system, the modeling process will become more complicated especially if modeled by using mathematical representation or white box approach. Therefore Computed Aided Design (CAD) modeling approach is more suitable to be applied in this system. In this paper presents the development of the CAD model of robot arm by using SolidWorks software. Then a controller based on Proportional-integral-derivative (PID) has been designed in simulation environment by using Matlab/Simulink platform. This paper shows the advantages of the combination of MATLAB and SolidWorks. SolidWorks is able to ease the modeling process. The performance of PID controller for 4 Degree of Freedom (DOF) of SCARA (Selective Compliance Articulated Robot Arm) manipulator has been assessed for first 2 DOF and shown good results

Fraud, investments and liability regimes in payment platforms

In this paper, we discuss how fraud liability regimes impact the price structure that is chosen by a monopolistic payment platform, in a setting where merchants can invest in fraud detection technologies. We show that liability allocation rules distort the price structure charged by platforms or banks to consumers and merchants with respect to a case where such a responsibility regime is not implemented. We determine the allocation of fraud losses between the payment platform and the merchants that maximises the platform's profit and we compare it to the allocation that maximises social welfare. JEL Classification: G21, L31, L42fraud, interchange fees, liability, Payment card systems, two-sided markets

Short-run forecasting of the euro-dollar exchange rate with economic fundamentals

Incluye bibliografíaWe propose a fundamentals-based econometric model for the weekly changes in the euro-dollar rate with the distinctive feature of mixing economic variables quoted at different frequencies. The model obtains good in-sample fi t and, more importantly, encouraging outof- sample forecasting results at horizons ranging from one week to one month. Specifi cally, we obtain statistically signifi cant improvements upon the hard-to-beat random walk model using traditional statistical measures of forecasting error at all horizons. Moreover, our model improves greatly when we use the direction-of-change metric, which has more economic relevance than other loss measures. With this measure, our model performs much better at all forecasting horizons than a naive model that predicts the exchange rate has an equal chance to go up or down, with statistically signifi cant improvementsSe propone un modelo econométrico basado en fundamentales para el cambio semanal del tipo de cambio del euro frente al dólar con la característica diferencial de mezclar variables con diferentes frecuencias. El modelo obtiene buenas predicciones en la muestra, y, lo que es más importante, mejoras en predicción fuera de la muestra a horizontes entre una semana y un mes. Específi camente, obtenemos mejoras estadísticamente signifi cativas frente al difícil de batir paseo aleatorio, usando las medidas tradicionales basadas en error de predicción cuadrático medio a todos los horizontes. Las ganancias son mayores cuando utilizamos la métrica basada en la dirección del cambio, que tiene más sentido económico en un modelo como este. Con esta medida, nuestro modelo predice los movimientos alcistas y bajistas del tipo de cambio mucho mejor que un modelo basado en igual probabilidad de bajadas y subida

An Investigation of Thresholds in Air Pollution-Mortality Effects

In this paper we introduce and implement new techniques to investigate threshold effects in air pollution-mortality relationships. Our key interest is in measuring the dose-response relationship above and below a given threshold level where we allow for a large number of potential explanatory variables to trigger the threshold effect. This is in contrast to existing approaches that usually focus on a single threshold trigger. We allow for a myriad of threshold effects within a Bayesian statistical framework that accounts for model uncertainty (i.e. uncertainty about which threshold trigger and explanatory variables are appropriate). We apply these techniques in an empirical exercise using daily data from Toronto for 1992-1997. We investigate the existence and nature of threshold effects in the relationship between mortality and ozone (O3), total particulate matter (PM) and an index of other conventionally occurring air pollutants. In general, we find the effects of our considered pollutants on mortality to be statistically indistinguishable from zero with no evidence of thresholds. The one exception is ozone, for which results present an ambiguous picture. Ozone has no significant effect on mortality when we exclude threshold effects from the analysis. Allowing for thresholds we find a positive and significant effect for this pollutant when the threshold trigger is the average change in ozone two days ago. However, this significant effect is not observed after controlling for PM.Threshold-air pollution mortality effects; Bayesian model; averaging; PM; O3

Fraud, Investments and Liability Regimes in Payment Platforms

In this paper, we discuss how fraud liability regimes impact the price structure that is chosen by a monopolistic payment platform, in a setting where merchants can invest in fraud detection technologies. We show that liability allocation rules distort the price structure charged by platforms or banks to consumers and merchants with respect to a case where such a responsibility regime is not implemented. We determine the allocation of fraud losses between the payment platform and the merchants that maximises the platform's profit and we compare it to the allocation that maximises social welfare

Subject strategies in music : a psychoanalytic approach to musical signification

This book develops psychoanalytic music criticism in the field of postmodern music analysis. It offers psychoanalytic listenings of various musics; from a Romantic symphony to alternative country music, from piano miniatures to TV-opera. The musical rhetoric of melancholy, uncanny, acoustic mirroring, alienation and other subjectivity mechanisms are tracked in the music of Chopin (Nocturne C minor Op. 48), k.d. lang (Constant Craving, Save me), Nordgren (Alex), Schubert (Der Lindenbaum), Sibelius (Kyllikki), and Tchaikovsky (Symphony No. 6, Pathétique). The book also outlines the history and current state of psychoanalytic music analysis and theorizes music as a site of subjectivity

Variety Gains of Trade Integration in a Heterogeneous Firm Model

The present paper studies the variety gains of regional integration in Asia. Applying a heterogenous firm model we are able to assess the gains arising from the increased product and consumer choice, which is not possible in trade models with representative firms. We analyse the impacts of the ongoing trade liberalisation in South East Asia in three scenarios: CIFTA, ASEAN+3, and ASEAN+6. We find that the gains from trade integration are substantial, particularly in the multilateral liberalisation scenario ASEAN+6. A multilateral reduction of fixed and variable trade barriers by 15 percent results in a trade growth of 34 percent, which due to the additional extensive margin of trade, is larger than in trade models with representative firms. Similarly, due to the additional gains from variety growth, the welfare gains of trade integration in Asia are up to 9 percent higher than trade models with representative firms would predict