4,073 research outputs found

    Controlling Urban Air Pollution Caused by Households: Uncertainty, Prices, and Income

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    We examine the control of air pollution caused by households burning wood for heating and cooking in the developing world. Since the problem is one of controlling emissions from nonpoint sources, regulations are likely to be directed at household choices of wood consumption and combustion technologies. Moreover, these choices are subtractions from, or contributions to, the pure public good of air quality. Consequently, the efficient policy design is not independent of the distribution of household income. Since it is unrealistic to assume that environmental authorities can make lump sum income transfers part of control policies, efficient control of air pollution caused by wood consumption entails a higher tax on wood consumption and a higher subsidy for more efficient combustion technologies for higher income households. Among other difficulties, implementing a policy to promote the adoption of cleaner combustion technologies must overcome the seemingly paradoxical result that efficient control calls for higher technology subsidies for higher income households.efficiency, urban air pollution, nonpoint pollution, environmental policy, uncertainty

    STIM map: detection map for exoplanets imaging beyond asymptotic Gaussian residual speckle noise

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    Direct imaging of exoplanets is a challenging task as it requires to reach a high contrast at very close separation to the star. Today, the main limitation in the high-contrast images is the quasi-static speckles that are created by residual instrumental aberrations. They have the same angular size as planetary companions and are often brighter, hence hindering our capability to detect exoplanets. Dedicated observation strategies and signal processing techniques are necessary to disentangle these speckles from planetary signals. The output of these methods is a detection map in which the value of each pixel is related to a probability of presence of a planetary signal. The detection map found in the literature relies on the assumption that the residual noise is Gaussian. However, this is known to lead to higher false positive rates, especially close to the star. In this paper, we re-visit the notion of detection map by analyzing the speckle noise distribution, namely the Modified Rician distribution. We use non-asymptotic analysis of the sum of random variables to show that the tail of the distribution of the residual noise decays as an exponential distribution, hence explaining the high false detection rate obtained with the Gaussian assumption. From this analysis, we introduce a novel time domain detection map and we demonstrate its capabilities and the relevance of our approach through experiments on real data. We also provide an empirical rule to determine detection threshold providing a good trade off between true positive and false positive rates for exoplanet detection

    Carbon-fiber tips for scanning probe microscopes and molecular electronics experiments

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    We fabricate and characterize carbon-fiber tips for their use in combined scanning tunneling and force microscopy based on piezoelectric quartz tuning fork force sensors. An electrochemical fabrication procedure to etch the tips is used to yield reproducible sub-100-nm apex. We also study electron transport through single-molecule junctions formed by a single octanethiol molecule bonded by the thiol anchoring group to a gold electrode and linked to a carbon tip by the methyl group. We observe the presence of conductance plateaus during the stretching of the molecular bridge, which is the signature of the formation of a molecular junction.Comment: Conference Proceeding (Trends in NanoTechnology 2011, Tenerife SPAIN); Nanoscale Research Letters, (2012) 7:25

    Management System for Harvest Scheduling: The Case of Horticultural Production in Southeast Spain

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    horticultural farmer, optimization, planning, mathematical programming, marketing, cooperative, Agribusiness, Crop Production/Industries, Demand and Price Analysis, Farm Management, Land Economics/Use,

    RoboToy Demoulding: Robotic Demoulding System for Toy Manufacturing Industry

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    Industrial environments and product manufacturing processes are currently being automated and robotized. Nowadays, it is common to have robots integrated in the automotive industry, robots palletizing in the food industry and robots performing welding tasks in the metal industry. However, there are many traditional and manual sectors out of date with technology, such as the toy manufacturing industry. This work describes a new robotic system able to perform the demoulding task in a toy manufacturing process, which is a tedious labor-intensive and potentially hazardous task for human operators. The system is composed of specialised machinery about the rotational moulding manufacturing process, cameras, actuators, and a collaborative robot. A vision-based algorithm makes this system capable of handling soft plastic pieces which are deformable and flexible during demoulding. The system reduces the stress and potential injuries to human operators, allowing them to perform other tasks wit h higher dexterity requirements or relocate to other sub-tasks of the process where the physical effort is minor

    A new automatic method for demoulding plastic parts using an intelligent robotic system

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    Nowadays, there are many different industrial processes in which people spend several hours performing tedious and repetitive tasks. Furthermore, most of these processes involve the manipulation of dangerous materials or machinery, such as the toy manufacturing, where people handle ovens with high temperatures and make weary physical effort for a long period of time during the process. In this work, it is presented an automatic and innovative collaborative robotic system that is able to deal with the demoulding task during the manufacturing process of toy dolls. The intelligent robotic system is composed by an UR10e robot with a RealSense RGB-D camera integrated which detects the pieces in the mould using a developed vision-based algorithm and extracts them by means of a custom gripper located and the end of the robot. We introduce a pipeline to perform the demoulding task of different plastic pieces relying in the use of this intelligent robotic system. Finally, to validate this approach, the automatic method has been successfully implemented in a real toy factory providing a novel approach in this traditional manufacturing process. The paper describes the robotic system performance using different forces and velocities, obtaining a success rate of more than 90% in the experimental results.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work has been carried out within the scope of an Industrial PhD at AIJU in the context of the SOFTMANBOT Project, with European funding from the Horizon 2022 research programme (G.A 869855). In addition, it has been supported by the UAIND21-06B grant of the University of Alicante

    A New Method for Finding Vacua in String Phenomenology

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    One of the central problems of string-phenomenology is to find stable vacua in the four dimensional effective theories which result from compactification. We present an algorithmic method to find all of the vacua of any given string-phenomenological system in a huge class. In particular, this paper reviews and then extends hep-th/0606122 to include various non-perturbative effects. These include gaugino condensation and instantonic contributions to the superpotential.Comment: 27 pages, 5 .eps figures. V2: Minor corrections, reference adde

    Impact of elite soccer coaching change on team performance according to coach- and club-related variables

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    A coaching change is an extreme, but frequently occurring phenomenon in elite soccer with its impact on team success debatable. The aim of the current study was twofold: (i) to compare team's performance when coached by new and old coaches; and (ii) to investigate the impact of a coaching change on team's performance according to coach- and club-related factors. All in-season coaching changes from the 2010-11 to 2017-18 seasons within the Spanish, French, English, German and Italian professional leagues were examined. Team performance was assessed as points awarded from match outcome over 1-20 matches prior to and following the coaching change. Four independent variables (coach's experience, team's budget, whether the coach had been an elite former player or not, and whether the coach was a novice or not) were included into linear regression modelling. The main results showed that team's short-term performance was improved significantly with a change to a new coach with this impact declining in the longer term (> 10 matches). Specifically, the number of points (1.15-1.32 vs. 0.37-1.03, p < 0.05) and the moving average of points (1.19-1.31 vs. 0.37-1.04, p < 0.05) awarded per match were significantly greater after the coaching change. Further, the winning effect due to the new coach was independent of coach-related factors such as coaching experience or the new coach being a former elite player. A critical organisational decision to change coaches may provide an essential stimulus for future team success in elite soccer
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