769 research outputs found

    The Incidental Environmental Agency

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    State oil and gas conservation agencies are the gatekeepers to oil and gas development: as the agencies charged with granting drilling permits, they decide if, when, where, and how oil and gas will be developed. As such, oil and gas conservation agencies sit on the front lines in the emerging, and increasingly irresolvable, struggle between fossil energy development and the environment. Current oil and gas conservation regulation is designed to promote development, maximize recovery of the resource, and protect the individual property rights of mineral owners. However, advocacy by environmental constituencies, including surface owners and local governments, has challenged the entrenched paradigm whereby production must be maximized at the expense of all other interests. These efforts are pushing courts to redefine oil and gas conservation according to twenty-first century environmental values. This Article examines the emergent environmental regulation function of oil and gas conservation agencies and identifies opportunities for these agencies to regulate according to their historic mandates in a manner that is inclusive of public values

    Siting Carbon Dioxide Pipelines

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    Waste and the Governance of Private and Public Property

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    Common law waste doctrine is often overlooked as antiquated and irrelevant. At best, waste doctrine is occasionally examined as a lens through which to evaluate evolutions in modern property theory. We argue here that waste doctrine is more than just a historical artifact. Rather, the principle embedded in waste doctrine underpins a great deal of property law generally, both common law and statutory, as well as the law governing oil and gas, water, and public trust resources. Seen for what it is, waste doctrine provides a fresh perspective on property, natural resources, and environmental law. In this Article, we excavate the old waste cases in multiple fields of property and natural resources law to make novel connections across these fields and demonstrate the doctrine\u27s continuing relevance for contemporary lawyers, legal theorists, and environmental advocates. The Article is unique in its articulation of a universal waste principle and its examination of how this principle facilitates communication and cooperative self-governance by and among owners of common property. It suggests that underenforcement of civil and administrative waste law in the context of common pool natural resources contributes to failures in modern law to respond to pressing environmental challenges

    Analysis of Distributed and Autonomous Scheduling Functions for 6tisch Networks

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    The 6TiSCH architecture is expected to play a significant role to enable the Internet of Things paradigm also in industrial environments, where reliability and timeliness are of paramount importance to support critical applications. Many research activities have focused on the Scheduling Function (SF) used for managing the allocation of communication resources in order to guarantee the application requirements. Two different approaches have mainly attracted the interest of researchers, namely distributed and autonomous scheduling. Although many different (both distributed and autonomous) SFs have been proposed and analyzed, a direct comparison of these two approaches is still missing. In this work, we compare some different SFs, using different behaviors in allocating resources, and investigate the pros and cons of using distributed or autonomous scheduling in four different scenarios, by means of both simulations and measurements in a real testbed. Based on our results, we also provide a number of guidelines to select the most appropriate SF, and its configuration parameters, depending on the specific use case

    LASA: Location-Aware Scheduling Algorithm In Industrial IoT Networks With Mobile Nodes

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    The Synchronized Single-hop Multiple Gateway (SHMG) is a framework recently proposed to support mobility into 6TiSCH, the standard network architecture defined for Industrial Internet of Things (IIoT) deployments. SHMG supports industrial applications with stringent requirements by adopting the Shared-Downstream Dedicated-Upstream (SD-DU) scheduling policy, which allocates to Mobile Nodes (MNs) a set of dedicated transmission opportunities for uplink data. Such allocation is performed on all the Border Routers (BRs) of the network without considering the location of MNs. Transmission opportunities are reserved also in BRs far from the current location of the MN, resulting in a waste of resources that limits the maximum number of nodes supported by the network. To overcome this problem, we propose a Location-Aware Scheduling Algorithm (LASA) that takes into account the position of MNs to build and maintain an efficient communication schedule. Specifically, LASA tries to prevent conflicts arising due to node mobility, in a preventive manner, so as to minimize packet dropping. We evaluate LASA via simulation experiments. Our results show that LASA allows to increase the number of MNs by more than four times, with respect to SD-DU, yet guaranteeing a Packet Delivery Ratio higher than 98%

    Mobility Management in Industrial Iot Environments

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    The Internet Engineering Task Force (IETF) has defined the 6TiSCH architecture to enable the Industrial Inter-net of Things (IIoT). Unfortunately, 6TiSCH does not provide mechanisms to manage node mobility, while many industrial applications involve mobile devices (e.g., mobile robots or wearable devices carried by workers). In this paper, we consider the Synchronized Single-hop Multiple Gateway framework to manage mobility in 6TiSCH networks. For this framework, we address the problem of positioning Border Routers in a deployment area, which is similar to the Art Gallery problem, proposing an efficient deployment policy for Border Routers based on geometrical rules. Moreover, we define a flexible Scheduling Function that can be easily adapted to meet the requirements of various IIoT applications. We analyze the considered Scheduling Function in different scenarios with varying traffic patterns and define an algorithm for sizing the system in such a way to guarantee the application requirements. Finally, we investigate the impact of mobility on the performance of the system. Our results show that the proposed solutions allow to manage node mobility very effectively, and without significant impact on the performance

    Floating matter: a neglected component of the ecological integrity of rivers

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    Floating matter (FM) is a pivotal, albeit neglected, element along river corridors contributing to their ecological integrity. FM consists of particulate matter of natural (e.g. wood, branches, leaves, seeds) and anthropogenic (e.g. plastic, human waste) origin as well as of organisms that, due to its properties, is able to float on the water surface. In this paper, we provide a comprehensive overview of the FM cycle and the fundamental environmental functions FM provides along rivers. Indeed, FM serves as an important geomorphological agent, a dispersal vector for animals and plant propagules, a habitat, a resource, and a biogeochemical component. Furthermore, we collected data on the amount of FM accumulating at dams and in reservoirs, and related it to key characteristics of the respective catchments. River fragmentation truncates the natural dynamics of FM through its extraction at damming structures, alteration in the flow regime, and low morphological complexity, which may decrease FM retention. Finally, we identify key knowledge gaps in relation to the role FM plays in supporting river integrity, and briefly discuss FM management strategies. (c) 2019, Springer Nature Switzerland AG.This work has been carried out within the SMART Joint Doctorate Programme ‘Science for the MAnagement of Rivers and their Tidal systems’, funded by the Erasmus Mundus programme of the European Union (http://www.riverscience.it). We also acknowledge financial support through the Excellence Initiative at the University of Tübingen, funded by the German Federal Ministry of Education and Research (BMBF) and the German Research Foundation (DFG). OS is thankful for a partial support from IGB equal opportunity fund for young female scientists and DFG (SU 405/10-1). SDL has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant agreement no. 748625

    Preparation and Properties of PTFE-PMMA Core-Shell Nanoparticles and Nanocomposites

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    he preparation of polytetrafluoroethylene-poly(methyl methacrylate) (PTFE-PMMA) core-shell particles was described, featuring controlled size and narrow size distribution over a wide compositional range, through a seeded emulsion polymerization starting from a PTFE seed of 26 nanometers. Over the entire MMA/PTFE range, the particle size increases as the MMA/PTFE ratio increases. A very precise control over the particle size can be exerted by properly adjusting the ratio between the monomer and the PTFE seed. Particles in the 80240 nm range can be prepared with uniformity indexes suited to build 2D and 3D colloidal crystals. These core-shell particles were employed to prepare nanocomposites with different compositions, through an annealing procedure at a temperature higher than the glass transition temperature of the shell forming polymer. A perfect dispersion of the PTFE particles within the PMMA matrix was obtained and optically transparent nanocomposites were prepared containing a very high PTFE amount
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