1,720,961 research outputs found
Interpreting per capita loads of organic matter and nutrients in municipal wastewater: A study on 168 Italian agglomerations
No full textThe size of an agglomeration is expressed in population equivalent, referring to the maximum average weekly load during the year according to the European Directive 271/91. This quantity, multiplied by the daily biochemical oxygen demand (BOD) produced by one population equivalent (which is 60 g d−1 PE−1, by definition), yields the design biodegradable organic load of the wastewater treatment plant. The same agglomeration size is compared against the capacity of the wastewater treatment plant (WWTP) for plant conformity verification by the European Commission. However, field observations show remarkable fluctuations of the daily mass flows entering a WWTP, often considerably below or above the expected load calculated according to the Directive prescriptions. A wrong estimation of the real influent load adversely affects the plant design and operation, and may lead to a misleading verification of its conformity to the agglomeration. In this work, a statistical data analysis on 168 agglomerations was performed, aiming at verifying the consistency between the expected loads of BOD, chemical oxygen demand (COD), nitrogen and phosphorus and the mass flows measured at the treatment plant inlet. Only 30–40% of the total analysed cases were found having an actual load compatible with the expected one. In these cases, the average per capita daily loads of BOD, COD, nitrogen and phosphorus, calculated over 2–3 years data pools, resulted: 44.6 ± 5.9, 82.4 ± 11, 9.4 ± 1.1, and 1.08 ± 0.13 g d−1, respectively, while the daily BOD per capita production of 60 g represented a value in between the 70th and the 90th percentiles of the actual daily load distributions. For the remaining 60–70% of the total cases, variably-remarkable positive or negative discrepancies between the nominal pollutant loads generated by the agglomeration and those measured at the plant inlet could be detected and possible causes were pointed out
Improving the quality of wastewater treatment plant monitoring by adopting proper sampling strategies and data processing criteria
No full textMonitoring is a crucial operation for plant management. However, proper sampling procedures and data processing criteria are not always adopted. Wastewater treatment plants work under dynamic conditions, which poses a challenge for a correct performance assessment. The aim of this work is to analyse some important aspects of wastewater sampling and data processing, to identify case by case methods which should to be adopted in order to obtain reliable and consistent information on plant performance. The study was conducted through simulations and real data analyses. It turned out that: a) the preferable 24-hour composite sampling procedure is the flow-proportional mode; in addition, the required sampling frequency (i.e. the number of sub-samples to be taken to make the 24-h composite sample) increases as the percentage of population discontinuously discharging the monitored substance decreases; b) a Variability Index was defined to help find the minimum sampling frequency (i.e. the number of 24-h composite samples per year) for the calculation of annual mass flows with an acceptable uncertainty; and c) criteria were proposed for the identification of pseudo-steady state periods needed to calculate reliable mass balances and plant performance indicators
Towards context-independent indicators for an unbiased assessment of environmental sustainability in higher education: An application to Italian universities
No full textHigher education institutes (HEIs) are important drivers for the development and implementation of best practices for environmental sustainability. However, reliable indicators are needed to objectively evaluate the environmental performance of HEIs and their policies. The present paper aims at identifying suitable indicators for unbiased comparisons among different HEIs and for the identification of temporal trends in terms of environmental sustainability performance. At this aim, sustainability reports made publicly available by 24 Italian HEIs over a 10-year period were considered. Normalization of sustainability variables such as the annual electrical and thermal energy consumptions, related greenhouse gas emissions, and water consumption, against context-specific factors such as the number of users of each university, latitude, illuminance, heating degree days (HDDs) and cooling degree days allowed identifying the actual possible disturbance of the same variables. HDDs were found to positively affect the thermal energy consumption and the related CO2 emissions. Based on this, a novel indicator was formulated where the actual value of thermal energy consumption and the related CO2 emissions are divided not only by the number of users but also by the HDDs of the HEIs’ locations. Indeed, this is a remarkable finding that, prior to confirmation with data from world HEIs, could be implemented in world university green ranking systems for improved and less biased sustainability assessments
Critical Analysis of the GreenMetric World University Ranking System: The Issue of Comparability
Full text linkThe Universitas Indonesia GreenMetric World Ranking is the most widely adopted system nowadays to rank worldwide universities' sustainability. The number of participating universities has consistently increased throughout the last decade. An in-depth analysis of this ranking system is made to assess how sustainability in universities is measured through specific indicators. Specifically, based on expert knowledge, common logic and the scientific literature, these indicators are assessed with respect to whether they can be used to fairly quantify and rank worldwide universities' sustainability development. Some indicators proposed by the ranking system, such as the number of renewable energy sources on campus and the number of various types of programs for sustainable development, were found to be unable to measure any sustainability development effectively and fairly. Many others, such as the opted sewage disposal modality, the percentage of university budget for sustainability efforts and the ratio of sustainability research funding to total research funding, were found to need adjustment to account for context-specific factors such as availability of renewable energy sources, weather, landscape, original construction and the cultural habits of the enrolled people. Taking into account these considerations, a fairer evaluation and comparison of universities' sustainability could be achieved which provides universities with information on how to effectively improve their sustainability
Towards a Structured Approach to Advance Sustainable Water Management in Higher Education Institutions: A Review
Full text linkThe aim of this paper is to investigate the measures adopted by higher education institutions (HEIs) for sustainable water management in university campuses. Rain and storm water harvesting and treatment, rain and storm water reuse, wastewater treatment and reuse and technologies for runoff reduction were found to be frequently undertaken. Sustainable approaches to water supply such as water-efficient appliances, irrigation algorithms and the use of drought-resistant plants have been adopted as well. In support, monitoring of consumed water and of rain and storm waters has been a widespread practice. Important considerations were given to the impact of the identified measures on campuses' energy consumption and greenhouse gas emissions. Nature-based solutions, employment of renewable energies and sustainable disinfection methods are measures to prioritize. Some wastewater technologies may deserve priority in virtue of their positive contribution to circular economy. Drawbacks such as groundwater and soil contamination due to wastewater reuse and the release of pollutants from fertilized nature-based technologies were identified. Despite their variety, it must be noted that many of these measures have generally involved rather limited portions of campuses, taken more for demonstration or pilot/full-scale research purposes. Additional measures not identified in the current review-for instance the prevention of pollution from micropollutants and waste mismanagement-should be implemented to boost HEIs' environmental sustainability. The findings of this review pave the way for a more structured implementation of water sustainability measures in university campuses
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
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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