1,720,957 research outputs found
Statistical analysis of incidents on onshore CO2 pipelines based on PHMSA database
No full textThe development of an integrated network for the management of carbon dioxide requires knowledge and optimization of all Carbon Capture Utilization and Storage (CCUS) aspects, including pipeline transport. Safety is one of the aspects that should be addressed prior CCUS facilities come in operation; the risk for people should be assessed to ensure it is below an acceptable level. In some cases, a quantitative risk assessment (QRA) is required by the approval authority. Normally the risk assessment is based on the use of statistical/historical data. However, for CO2 handling systems the operating experience is limited compared to hydrocarbon transporting systems and, for this reason, hydrocarbon pipeline statistics are normally used as a proxy. The only database that contains records on CO2 pipelines is the PHMSA since in the U.S. several CO2 pipelines have been constructed since the 1970's, essentially for Enhanced Oil Recovery operations. There is limited statistical data available compared to the hydrocarbon pipelines experience and therefore care should be taken when undertaking the frequency analysis. In this work an analysis of incidents data related to the onshore CO2 pipelines in the U.S. between 1985 and 2021 reported by the Pipeline Hazardous Material Safety Administration (PHMSA) of the U.S. Department of Transportation is presented. The aim of the study is to analyze the records contained in the PHMSA database to provide an estimate of a specific CO2 pipeline failure rate to be used in quantitative risk assessments. Concerns and limitations of the data have been also discussed
Statistical analysis of incidents on onshore CO2 pipelines based on PHMSA database
No full textThe development of an integrated network for the management of carbon dioxide requires knowledge and optimization of all Carbon Capture Utilization and Storage (CCUS) aspects, including pipeline transport. Safety is one of the aspects that should be addressed prior CCUS facilities come in operation; the risk for people should be assessed to ensure it is below an acceptable level. In some cases, a quantitative risk assessment (QRA) is required by the approval authority. Normally the risk assessment is based on the use of statistical/historical data. However, for CO2 handling systems the operating experience is limited compared to hydrocarbon transporting systems and, for this reason, hydrocarbon pipeline statistics are normally used as a proxy. The only database that contains records on CO2 pipelines is the PHMSA since in the U.S. several CO2 pipelines have been constructed since the 1970's, essentially for Enhanced Oil Recovery operations. There is limited statistical data available compared to the hydrocarbon pipelines experience and therefore care should be taken when undertaking the frequency analysis. In this work an analysis of incidents data related to the onshore CO2 pipelines in the U.S. between 1985 and 2021 reported by the Pipeline Hazardous Material Safety Administration (PHMSA) of the U.S. Department of Transportation is presented. The aim of the study is to analyze the records contained in the PHMSA database to provide an estimate of a specific CO2 pipeline failure rate to be used in quantitative risk assessments. Concerns and limitations of the data have been also discussed
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Development of improved strategies for the lay-out of fire and gas detectors
No full textFire and Gas (F&G) detection is an essential part of the mitigation system in facilities handling and storing flammable and toxic materials. While detector reliability might be very high, safety performance of a F&G system strongly depends on layout and coverage. Current reference standards for on-shore applications do not define the plant areas to be mapped, the coverage targets, and the reference hazardous scenarios to be considered. In the present study, a methodology aimed at the F&G coverage mapping was developed. The procedure is applicable in the Front End Engineering Design phase (FEED), where limited data is typically available. The development of the methodology considered the main aspects that define F&G system performance. Coverage targets for detection were set considering risk reduction goals and actual detector capabilities. Simple strategies were developed for the determination of the reference hazardous scenarios to be considered. A Matlab code for 3D F&G coverage mapping was developed. The proposed procedure was demonstrated by a simplified case study. The methodology proved itself a valid instrument to assist detector layout assessment. © Copyright 2014, AIDIC Servizi S.r.l
Risks and safety of co2 transport via pipeline: A review of risk analysis and modeling approaches for accidental releases
Full text linkCarbon capture and storage is considered an effective mitigation strategy to reduce the most challenging emissions from heavy industries and gas processing. The safe transport of carbon dioxide via pipelines is an important aspect for developing large-scale Carbon Capture and Storage projects. Dispersion modeling for heavy gas such as carbon dioxide is considerably different from natural gas. The set up for modeling simulations is more challenging than conventional natural gas pipeline for several reasons, such as the differences in thermodynamics that must be considered. Moreover, when the carbon dioxide is transported in dense or liquid phase, the rapid phase changing, and possible consequent formation of solids should be considered. Finally, the equation of state required for accurate prediction of parameters is generally different than the ones applicable for natural gas. The main scope of this comprehensive review is to identify the most important parameters, critical events, suitable models, and identification of dispersion modeling issues. An extensive literature review of experiments conducted in the last ten years has been developed, experimental data, integral and simplified model, as well as CFD modeling issues has been identified and reported in the work proposed to highlight the advances and the gaps that could need further research activities
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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