7,049 research outputs found

    On-line identification of seeds in mandarins with magnetic resonance imaging

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    Mandarins have been inspected using magnetic resonance imaging (MRI) in order to detect the presence of seeds. To enhance contrast between seeds and pulp, effective transverse relaxation time-weighted fast low angle shot images (703 ms acquisition time) were acquired. Stationary fruits were imaged and then the images were segmented to extract several features. The maximum radius of the region containing the seeds and the central axis rmax, and the perimeter of this region P were the most powerful features for discrimination between seedless and seed-containing fruits. Such features were the most robust since they showed the lowest noise-to-signal ratios (N/S). The proportions of correct classification were 88.9% and 86.7% for seedless and seed-containing fruits, respectively, under MRI stationary conditions. The performance under on-line conditions was evaluated by imaging the fruits while conveyed at 54 mm/s. An analysis of variance with the features extracted from the static images and the motion-corrected dynamic images showed that there were statistically indistinguishable. The proportions of correct classification were 92.5% and 79.5% for the seedless and seed-containing category, respectively, under MRI dynamic conditions. Reduction in the distance between categories for rmax was addressed as the main cause for the decrease in discrimination performance. The robustness of the motion correction procedure was highlighted by the low differences in the N/S ratio and the noise-to-measured range ratios between static and dynamic features

    An NMR study on internal browning in pears

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    Internal browning in pears (Pyrus communis L. cv. Blanquilla) has been studied by NMR and MRI in order to develop a non-destructive procedure for on-line disorder identification. For NMR relaxometry, disordered tissue shows higher transverse relaxation rates compared to sound tissue, especially at higher magnetic field strength and for long pulse spacing. Membrane alteration and therefore tissue disintegration, as well as water evaporation, appear to be the main causes of this response. Correlation between relaxation times and diffusion showed that the proton pools in disordered tissue are grouped into a smaller number of populations compared to sound tissue, also highlighting cell decompartmentation in disordered tissue. At a macroscopic level, fast low angle shot MR images, effective transverse relaxation-weighted (TR 11 ms and TE 3.7 ms) and proton density-weighted (TR 7.6 ms and TE 2.5 ms), were acquired for pears at a rate of 54 mm/s. Images have been discriminated for internal breakdown according to histogram characteristics. Up to 94 and 96% of pears, respectively, were correctly classified in the former and the latter type of images. In this study a minimum value of 12% of tissue affected by breakdown was always clearly identifie

    Robots, labor markets, and universal basic income

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    Automation is a big concern in modern societies in view of its widespread impact on many socioeconomic issues including income, jobs, and productivity. While previous studies have concentrated on determining the effects on jobs and salaries, our aim is to understand how automation affects productivity, and how some policies, such as taxes on robots or universal basic income, moderate or aggravate those effects. To this end, we have designed an experiment where workers make productive effort decisions, and managers can choose between workers and robots to do these tasks. In our baseline treatment, we measure the effort made by workers who may be replaced by robots, and also elicit firm replacement decisions. Subsequently, we carry out treatments in which workers have a universal basic income of about a fifth of the workers’ median wages, or where there is a tax levy on firms who replace workers by robots. We complete the picture of the impact of automation by looking into the coexistence of workers and robots with part-time jobs. We find that the threat of a robot substitution does not affect the amount of effort exerted by workers. Also, neither universal basic income nor a tax on robots decrease workers’ effort. We observe that the robot substitution tax reduces the probability of worker substitution. Finally, workers that benefit from managerial decisions to not substitute them by more productive robots do not increase their effort level. Our conclusions shed light on the interplay of policy and workers behavior under pervasive automation

    Robots, labor markets, and universal basic income

    Get PDF
    Automation is a big concern in modern societies in view of its widespread impact on many socioeconomic issues including income, jobs, and productivity. While previous studies have concentrated on determining the effects on jobs and salaries, our aim is to understand how automation affects productivity, and how some policies, such as taxes on robots or universal basic income, moderate or aggravate those effects. To this end, we have designed an experiment where workers make productive effort decisions, and managers can choose between workers and robots to do these tasks. In our baseline treatment, we measure the effort made by workers who may be replaced by robots, and also elicit firm replacement decisions. Subsequently, we carry out treatments in which workers have a universal basic income of about a fifth of the workers’ median wages, or where there is a tax levy on firms who replace workers by robots. We complete the picture of the impact of automation by looking into the coexistence of workers and robots with part-time jobs. We find that the threat of a robot substitution does not affect the amount of effort exerted by workers. Also, neither universal basic income nor a tax on robots decrease workers’ effort. We observe that the robot substitution tax reduces the probability of worker substitution. Finally, workers that benefit from managerial decisions to not substitute them by more productive robots do not increase their effort level. Our conclusions shed light on the interplay of policy and workers behavior under pervasive automation

    Corso, un buldog con ansiedad por separación

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    Se describe un caso de ansiedad por separación en un Buldog Francés macho de 1,7 años de edad. Sus dueños acuden a la consulta, ya que Corso destroza todo cuando se queda solo en casa. En un primer momento fue el salón, en donde fue necesario realizar obras de reparación de los destrozos provocados por el paciente. En la actualidad es un pasillo, su nueva ubicación cuando está solo. El tratamiento se compuso de tres partes: terapia farmacológica consistente en Trankimazin 1mg 1/24h y Fluoxetina 20mg 1/24h, la modificación de su entorno y una modificación de conducta, facilitada por el propio tratamiento farmacológico. Siete meses después, tras varios seguimientos, Corso es dado el alta, prolongándole el tratamiento farmacológico de Fluoxetina, media dosis durante un mes más.Privateering is described to a case of separation anxiety in a French Bulldog of 1,7 years, called Corso. The owners go to the clinic because Corso destroys everything when left alone at home. Initially was the living room where they had to make repairs of damage caused by Corso. Currently is a corridor, its new location when left alone. Treatment consisted of three parts: first the pharmacological treatment Trankimazin 1mg 1/24h and Fluoxetina 20mg 1/24h, then changing his environment and also a behavior modification helped by the pharmalogical treatment. Seven months later, and after several follow-ups, Corso was medical discharged but the pharmacological treatment was maintained for a month with half dose of Fluoxetina

    Graphical tools for helping firefighters in victim rescues. Assessment during a live fire training program

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    This study compares three different methods to communicate the features of a building to firefighters, before starting a victim rescue during a live fire training program. Participants in this study did not previously know the hotel used for developing the activities. The effective number of participants was 144, all professional firefighters. One of the exercises in this training program was thoroughly designed not only for training purposes, but also to test different guide versions. The innovative guides were based on two different technologies (simple stapled sheets of paper and digital content displayed on a tablet) and were developed using several graphical tools (conventional pictures, aerial images captured with drone, 3D models, 360° pictures, etc.). With the intention of facilitating firefighters’ activity during a victim rescue, results obtained using these tools were compared with a conventional communication method. The assessment methodology applied in this study included the use of an anonym questionnaire, as well as the analysis of the videos captured with action cameras, attached with a harness to the chest of two of the four firefighters in every team, during the training activities. Thanks to these videos, it was possible to compare the time required for rescuing the victim and to observe followed paths, visited rooms and substantial information about the tested tools, including valuable participants’ comments. For in emergency situations, the tools described in this paper were preferred to the already existent self-protection plans, usually considered too extensive for fast communication, a matter of special importance in victim rescues

    “Male effect” and “temporary weaning” in synchronization of post-partum ovarian activity in Pelibuey ewes

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    To evaluate the response of the “male effect” and “temporary weaning” on the synchronization of post-partum ovarian activity in Pelibuey ewes, an experiment was carried out using 78 Pelibuey ewes with suckling lambs. The ewes were separated from their offspring for 48 hours and randomly assigned to one of four treatments derived from the arrangement of two factors, “male effect” and “temporary weaning”, each at two levels. Treatments were: T1 (n = 20) control ewes, without “male effect” and without “temporary weaning”); T2 (n = 19) ewes without “male effect” and with “temporary weaning”; T3 (n = 20) ewes with “male effect” and without “temporary weaning”; and T4 (n = 19), ewes with “male effect” and with “temporary weaning”. The response to oestrus, return to oestrus, gestation rate and lambing rate were analysed using logistic regression. The onset of oestrus was analysed using survival curves. No significant differences were found for lambing rate and prolificacy among treatments. “Temporary weaning” (T2) and “male effect” (T3) did not influence the response to oestrus, rate and duration of return to oestrus, or gestation rate and fertility, and was similar to the control group (T1). The interaction of “male effect” with “temporary weaning” (T4) increased the response to oestrus, reduced the rate and duration of return to oestrus, and the gestation rate, but increased fertility. Synchronizing post-partum ovarian activity with “male effect” and “temporary weaning” reduces the onset of oestrus and the rate of return to oestrus, but increases the response to oestrus and fecundity in Pelibuey ewes.Keywords: Biostimulation, progestogens, prolificacy, prostaglandins, sucklin
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