428 research outputs found

    Assessing the Efficiency of a PSS Solution for Waste Collection: A Simulation Based Approach ☆

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    Abstract Driven by both policy pressures and environmental concerns, new business models are becoming applied in waste management mainly based on introducing more equitable and sustainable pricing schemes (e.g. "pay-as-you-throw"): the aim is to support the transition from a tax based system to a pure service based approach, where the user pays for the actual use of the waste management service provided. This new trend requires the service provider's activities to be planned with a schedule that reflects the actual users' needs in order to reach a real efficiency in the collection phase: dynamic routing and scheduling schemes, which could be enabled through the application of smart technologies, can lead to a more rational use of the resources. In the last decade, technological progresses allowed a growing use of IoT (Internet-of-Things) applications in the service sector; recent pilot applications are being tested also in waste management; one example is the introduction of bin level detection and data transmission technologies for waste collection. This work aims to contribute to the assessment of IoT-based PSS solutions for waste collection. The main objective is to evaluate the cost efficiency of a PSS for waste collection enabling dynamic scheduling, comparing it to the performance of more common schemes (e.g. fixed routing and scheduling service and call-based service). Hybrid simulation modelling – based on system dynamics, discrete events and agent based modelling- has been applied to test the transition from a fixed to a "pay-as-you-throw" fee in WEEE (waste from electrical and electronic equipment). A test case regarding an Italian municipality has been proposed to assess quantitative results based on a simulation model

    Efecto de la defoliación post-quema sobre el crecimiento de dos gramíneas nativas en el Caldenal, Argentina

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    El crecimiento en los pastizales naturales semiáridos puede ser afectado por la longitud de tiempo que el pastoreo es excluido durante el período de regeneración post-fuego. El objetivo de este trabajo a campo fue estudiar el efecto de la defoliación post-fuego en diferentes estados fenológicos: vegetativo (defoliación temprana) y elongación de entrenudos (defoliación tardía) sobre el crecimiento de Piptochaetium napostaense y Poa ligularis, dos gramíneas nativas perennes muy importantes en la región semiárida templada central de Argentina (Caldenal). En general, los tratamientos de defoliación post-quema no afectaron el número de hojas verdes en las macollas de P. napostaense. La defoliación temprana después del tratamiento de fuego generalmente redujo el número de hojas verdes en las macollas de P. ligularis con respecto a las plantas control. Contrariamente, la defoliación tardía usualmente incrementó el número de hojas verdes en las macollas de P. ligularis. Sin embargo, en ambos casos, muy pocas de las diferencias detectadas fueron significativas (p0,05) a aquellas de las plantas no defoliadas. Inmediatamente después de los tratamientos de defoliación temprana y tardía, las tasas de crecimiento relativas de la altura y la longitud verde total de las macollas de las plantas de ambas especies fueron reducidas (p0.05) than values on non-defoliated plants, respectively. Immediately after early- and late-season defoliation treatments, relative growth rates for tiller height and total green length were reduced (p<0.05) on plants of both species with respect to control plants. Our results suggest that a one-year-period without severe defoliations after fire would be at least necessary for not risking the persistence of these perennial grasses in the Caldenal community.Fil: Pelaez, Daniel Valerio. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Boo, Roberto Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Mayor, M. D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Elia, Omar Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Martinez, S. A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentin

    Integrating Safety-I and Safety-II Approaches in Near Miss Management: A Critical Analysis

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    Safety-II is a recently theorized approach, considering safety as the ability of a system to reach a positive outcome under variable conditions: analyzing “what goes right” can help to understand the dynamics of the analyzed system and improve its inherent safety level. On the contrary, a more traditional perspective, defined as Safety-I, aims at analyzing “what goes wrong”, thereby relating the safety level of a system to the number of adverse events that occurred. This study explores the potentialities of integrating these two approaches in near-miss management. Through a Safety-I approach, near-miss events are analyzed to identify the root causes generating the event chain, in order to delete them and prevent future accidents. Applying a Safety-II approach, the analysis can include elements that contributed to limiting the consequences and blocking the event chain, revealing the resilience level of the systems. This study presents a critical analysis of the two approaches and proposes a practical framework to integrate them into near-miss management systems. A test case shows the potential benefits of this integration. This work provides a tool to support the implementation of Safety-II on the operative level while suggesting a new perspective for near-miss management

    Performance Evaluation of an IoT Sensor Node for Health Monitoring of Artwork and Ancient Wooden Structures

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    In this paper, an IoT sensor node, based on smart Bluetooth low energy (BLE), for the health monitoring of artworks and large wooden structures is presented. The measurements from sensors on board the node are collected in real-time and sent to a remote gateway. The sensor node allows for the monitoring of environmental parameters, in particular, temperature and humidity, with accurate and robust integrated sensors. The developed node also embeds an accelerometer, which also allows other mechanical quantities (such as tilt) to be derived. This feature can be exploited to perform structural monitoring, exploiting the processing of data history to detect permanent displacements or deformations. The node is triggered by acceleration transients; therefore, it can also generate alarms related to shocks. This feature is crucial, for instance, in the case of transportation. The developed device is low-cost and has very good performance in terms of power consumption and compactness. A reliability assessment showed excellent durability, and experimental tests proved very satisfactory robustness against working condition variations. The presented results confirm that the developed device allows for the realization of pervasive monitoring systems, in the context of the IoT paradigm, with sensor nodes devoted to the monitoring of each artwork present in a museum or in a church

    Intermodal Terminal Subsystem Technology Selection Using Integrated Fuzzy MCDM Model

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    Intermodal transportation is the use of multiple modes of transportation, which can lead to greater sustainability by reducing environmental impact and traffic congestion and increasing the efficiency of supply chains. One of the preconditions for efficient intermodal transport is the efficient intermodal terminal (IT). ITs allow for the smooth and efficient handling of cargo, thus reducing the time, cost, and environmental impact of transportation. Adequate selection of subsystem technologies can significantly improve the efficiency and productivity of an IT, ultimately leading to cost savings for businesses and a more efficient and sustainable transportation system. Accordingly, this paper aims to establish a framework for the evaluation and selection of appropriate technologies for IT subsystems. To solve the defined problem, an innovative hybrid multi-criteria decision making (MCDM) model, which combines the fuzzy factor relationship (FFARE) and the fuzzy combinative distance-based assessment (FCODAS) methods, is developed in this paper. The FFARE method is used for obtaining criteria weights, while the FCODAS method is used for evaluation and a final ranking of the alternatives. The established framework and the model are tested on a real-life case study, evaluating and selecting the handling technology for a planned IT. The study defines 12 potential variants of handling equipment based on their techno-operational characteristics and evaluates them using 16 criteria. The results indicate that the best handling technology variant is the one that uses a rail-mounted gantry crane for trans-shipment and a reach stacker for horizontal transport and storage. The results also point to the conclusion that instead of choosing equipment for each process separately, it is important to think about the combination of different handling technologies that can work together to complete a series of handling cycle processes. The main contributions of this paper are the development of a new hybrid model and the establishment of a framework for the selection of appropriate IT subsystem technologies along with a set of unique criteria for their evaluation and selection

    Does the kart fit?

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    Background: the incidence of biomechanical pain related to Go-Kart Racing remains high, as high studies are not made due to the fact that racing with a go-kart is often not intended as arrival point but as a starting point of major racing career. In light of discontinuous racing pain, no theories about biomechanics have been suggested as possible contributor to solve the racing related pain. Perhaps no study has been conducted on the biomechanics of go-kart racing. However, the decision making process for the determination of the best racing position affecting driver’s symptoms has not been described. Therefore, the purpose of this case report is to describe the biomechanical reasoning within the go-kart racing framework for a group of four driver reporting different symptoms

    Respuesta de la vegetación a un fuego controlado en la Provincia Fitogeográfica del Monte, Argentina

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    El fuego es un proceso ecológico clave en la mayoría de los ecosistemas terrestres. Por lo tanto, la comprensión de la respuesta de la vegetación al fuego es esencial para su manejo. El objetivo de este trabajo fue estudiar el efecto de un fuego controlado, realizado a fines del verano, sobre la cobertura y densidad de las principales especies leñosas y herbáceas en la Provincia Fitogeográfica del Monte, Argentina. En general, después del fuego controlado el porcentaje de cobertura media de las especies leñosas fue significativamente menor (p0,05) en la densidad media de las especies leñosas a lo largo del período de estudio. La cobertura foliar media de las gramíneas perennes deseables, excepto en dos fechas de muestreo, fue significativamente mayor (p0,05) entre tratamientos en la densidad de las gramíneas perennes deseables. La densidad de las gramíneas perennes intermedias fue consistentemente menor en el tratamiento quemado que en el tratamiento control, pero sólo ocasionalmente las diferencias fueron significativas (p0.05) were detected in woody species mean density among treatments throughout the whole study. Desirable perennial grass mean percentage foliar cover, except at two sampling dates, was higher (p<0.05) in the controlled fire treatment than in the control. Contrarily, mean percentage foliar cover of intermediate perennial grasses was lower in the fire treatment than in the control, although differences were not always significant (p<0.05). No significant differences (p<0.05) in desirable perennial grass density were detected among treatments. Intermediate perennial grass density was consistently lower in the fire than in the control treatment, although differences were not always significant at p<0.05. Desirable annual grass and forb foliar covers were slightly higher in the fire than in the control treatment. Our results suggest that the reduction of woody species cover might have favored the foliar cover increase of the desirable perennial grasses. Moreover, our results suggest that a single, controlle burn would not seem to start a plant species replacement sequence, and that the plant community would persist with no variation in the density of the major woody species and the most prominent perennial grasses.Fil: Pelaez, Daniel Valerio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Giorgetti, Hugo Dosindo. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios. Chacra Experimental de Patagones; ArgentinaFil: Montenegro, Oscar Alberto. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios. Chacra Experimental de Patagones; ArgentinaFil: Elia, Omar Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Rodriguez, Gustavo Dionisio. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios. Chacra Experimental de Patagones; ArgentinaFil: Boo, Roberto Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Mayor, Mirta Doris. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Busso, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentin
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