40,840 research outputs found

    What’s Shakin’? Ladra v. New Dominion, LLC: A Case of Consequence for the Hydraulic Fracturing Industry and Those Affected by Induced Seismicity

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    This analysis is accompanied by a study of a 2015 ruling of the Supreme Court of Oklahoma, Ladra v. New Dominion, LLC. The case considered the possibility of a private tort action by homeowners against the operators of injection wells proceeding within the state’s judicial system, rather than simply being subject to review by a state regulatory agency. The court ultimately decided that the case would be allowed to continue within the judicial system instead of in front of a regulatory agency. This case, while not providing a “silver bullet” precedent with which future claimants can automatically win their cases against parties involved in fracking and waste disposal, does demonstrate that these claims are viable and ought to be dealt with in proper courts of law, rather than through administrative agencies. Section II of this case note contains a brief overview of the hydraulic fracturing process and the state of fracking in Oklahoma, the site of this note’s principal case (Ladra v. New Dominion). Section III provides a history of the case and its central issues. Section IV discusses the ruling given, as well as the validity of the arguments made before the court. Section V examines the likelihood of success for the plaintiff Ladra and other homeowners seeking damages from the operators of injection wells due to earthquake-related harm done to their property or person. This section primarily assesses whether a preponderance of the evidence standard can be achieved when alleging that fracking activities caused earthquakes that resulted in property damage, and uses the arguments presented in the lower court during Ladra v. New Dominion as an example. Section VI considers the significance of the decision and what effect it may have on the hydraulic fracturing industry

    Improving reconfigurable systems reliability by combining periodical test and redundancy techniques: a case study

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    This paper revises and introduces to the field of reconfigurable computer systems, some traditional techniques used in the fields of fault-tolerance and testing of digital circuits. The target area is that of on-board spacecraft electronics, as this class of application is a good candidate for the use of reconfigurable computing technology. Fault tolerant strategies are used in order for the system to adapt itself to the severe conditions found in space. In addition, the paper describes some problems and possible solutions for the use of reconfigurable components, based on programmable logic, in space applications

    Model-based dependability analysis : state-of-the-art, challenges and future outlook

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    Abstract: Over the past two decades, the study of model-based dependability analysis has gathered significant research interest. Different approaches have been developed to automate and address various limitations of classical dependability techniques to contend with the increasing complexity and challenges of modern safety-critical system. Two leading paradigms have emerged, one which constructs predictive system failure models from component failure models compositionally using the topology of the system. The other utilizes design models - typically state automata - to explore system behaviour through fault injection. This paper reviews a number of prominent techniques under these two paradigms, and provides an insight into their working mechanism, applicability, strengths and challenges, as well as recent developments within these fields. We also discuss the emerging trends on integrated approaches and advanced analysis capabilities. Lastly, we outline the future outlook for model-based dependability analysis

    Software that Learns from its Own Failures

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    All non-trivial software systems suffer from unanticipated production failures. However, those systems are passive with respect to failures and do not take advantage of them in order to improve their future behavior: they simply wait for them to happen and trigger hard-coded failure recovery strategies. Instead, I propose a new paradigm in which software systems learn from their own failures. By using an advanced monitoring system they have a constant awareness of their own state and health. They are designed in order to automatically explore alternative recovery strategies inferred from past successful and failed executions. Their recovery capabilities are assessed by self-injection of controlled failures; this process produces knowledge in prevision of future unanticipated failures

    Comparison of different classification algorithms for fault detection and fault isolation in complex systems

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    Due to the lack of sufficient results seen in literature, feature extraction and classification methods of hydraulic systems appears to be somewhat challenging. This paper compares the performance of three classifiers (namely linear support vector machine (SVM), distance-weighted k-nearest neighbor (WKNN), and decision tree (DT) using data from optimized and non-optimized sensor set solutions. The algorithms are trained with known data and then tested with unknown data for different scenarios characterizing faults with different degrees of severity. This investigation is based solely on a data-driven approach and relies on data sets that are taken from experiments on the fuel system. The system that is used throughout this study is a typical fuel delivery system consisting of standard components such as a filter, pump, valve, nozzle, pipes, and two tanks. Running representative tests on a fuel system are problematic because of the time, cost, and reproduction constraints involved in capturing any significant degradation. Simulating significant degradation requires running over a considerable period; this cannot be reproduced quickly and is costly

    On Systematic Design of Protectors for Employing OTS Items

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    Off-the-shelf (OTS) components are increasingly used in application areas with stringent dependability requirements. Component wrapping is a well known structuring technique used in many areas. We propose a general approach to developing protective wrappers that assist in integrating OTS items with a focus on the overall system dependability. The wrappers are viewed as redundant software used to detect errors or suspicious activity and to execute appropriate recovery when possible; wrapper development is considered as a part of system integration activities. Wrappers are to be rigorously specified and executed at run time as a means of protecting OTS items against faults in the rest of the system, and the system against the OTS item's faults. Possible symptoms of erroneous behaviour to be detected by a protective wrapper and possible actions to be undertaken in response are listed and discussed. The information required for wrapper development is provided by traceability analysis. Possible approaches to implementing “protectors” in the standard current component technologies are briefly outline
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