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An assessment of non-revenue water for Norton Town in Zimbabwe.
No full textABSTRACT
Water is an important natural resource and urban water utilities in Southern Africa are facing challenges in the provision of potable water supply. Non-Revenue Water (NRW) is one of the challenges affecting water provision in developing countries. Norton Town Council is mandated by the government to provide safe and adequate water to the residents of Norton. The town is faced with a challenge of limited water supply, with a supply of 7 500m3/day against an estimated demand of 15000 m3/day. This is against a background of high NRW in the region. Therefore, this study sought to assess the extent of NRW for Norton and its components. An evaluation of possible strategies to control NRW was also done. To determine NRW for the town, historical data from 2004 to 2015 was collected and analysed. From the historical data comparison of the bulk water received and billed consumption volume was done to determine overall NRW. Partitioning of water losses was done through Minimum Night Flow (MNF) analysis focusing on two distinct zones of the town which are Galloway and Katanga-Ngoni. Norton town is characterised by intermittent supply, therefore to perform MNF the water supply system was manipulated in order to create continuous flows as recommended. The results obtained were true for the testing period and to correct for intermittent supply correction factors were applied. Correction factors were determined based on the leakage theory which relates pressure to leakage. To evaluate the operating practices in the water supply system qualitative and quantitative data was collected through key informant interviews, questionnaires and meter testing. Multi-Criteria Decision Analysis (MCDA) was used to evaluate strategies to control NRW. MCDA used the data and information collected in the study to determine criterion and objectives in the analysis. Results from the study showed that the average NRW for the town from 2004 to 2015 was 34 % which is above regional benchmarks of 20 % to 25 %. This was attributed to absence of active leakage management, high metering inaccuracies, partial water billing in some areas of the town and manual meter reading instead of use of available automated data loggers. Partial billing suggests that residents in those areas may have free access to water contributing to NRW. Meter testing showed that 73 % of the tested meters were under registering consumption. The average NRW for the two areas were 65 % for Galloway and 76 % for Katanga-Ngoni. Partitioning of water losses for Galloway revealed that real losses were 26 % and apparent losses 74 %. In Katanga-Ngoni, real losses were 35 % and apparent losses 65%. The apparent losses for both areas are above recommended limit range of 20 % to 40 %, indicating a poorly managed system in terms of billing and metering. Apparent losses were attributed to a poor metering system characterised by use of non-functional meters and absence of a regulatory policy on metering and billing. Management of the water supply system by the local authority is fragmented between the departments responsible for water supply. This has resulted in inefficient use of equipment and infrastructure provided for improving water management. Controlling commercial losses was ranked first as a strategy to control NRW followed by integrated management and reduction of physical water losses respectively. The recommendations were to update the customer database and improve on metering. It was also recommended that utilisation of available zonal meters and data loggers be done so that both apparent and real losses are controlled. The study also suggested integrated management of the water system so that departmental goals on water services are the same.,WaterNe
An Assessment of Non-Revenue Water for Norton Town in Zimbabwe
No full textWater is an important natural resource and urban water utilities in Southern Africa are facing
challenges in the provision of potable water supply. Non-Revenue Water (NRW) is one of the
challenges affecting water provision in developing countries. Norton Town Council is
mandated by the government to provide safe and adequate water to the residents of Norton.
The town is faced with a challenge of limited water supply, with a supply of 7 500m3/day
against an estimated demand of 15 000 m3/day. This is against a background of high NRW in
the region. Therefore, this study sought to assess the extent of NRW for Norton and its
components. An evaluation of possible strategies to control NRW was also done. To
determine NRW for the town, historical data from 2004 to 2015 was collected and analysed.
From the historical data comparison of the bulk water received and billed consumption
volume was done to determine overall NRW. Partitioning of water losses was done through
Minimum Night Flow (MNF) analysis focusing on two distinct zones of the town which are
Galloway and Katanga-Ngoni. Norton town is characterised by intermittent supply, therefore
to perform MNF the water supply system was manipulated in order to create continuous
flows as recommended. The results obtained were true for the testing period and to correct for
intermittent supply correction factors were applied. Correction factors were determined based
on the leakage theory which relates pressure to leakage. To evaluate the operating practices in
the water supply system qualitative and quantitative data was collected through key informant
interviews, questionnaires and meter testing. Multi-Criteria Decision Analysis (MCDA) was
used to evaluate strategies to control NRW. MCDA used the data and information collected
in the study to determine criterion and objectives in the analysis. Results from the study
showed that the average NRW for the town from 2004 to 2015 was 34 % which is above
regional benchmarks of 20 % to 25 %. This was attributed to absence of active leakage
management, high metering inaccuracies, partial water billing in some areas of the town and
manual meter reading instead of use of available automated data loggers. Partial billing
suggests that residents in those areas may have free access to water contributing to NRW.
Meter testing showed that 73 % of the tested meters were under registering consumption. The
average NRW for the two areas were 65 % for Galloway and 76 % for Katanga-Ngoni.
Partitioning of water losses for Galloway revealed that real losses were 26 % and apparent
losses 74 %. In Katanga-Ngoni, real losses were 35 % and apparent losses 65%. The apparent
losses for both areas are above recommended limit range of 20 % to 40 %, indicating a poorly
managed system in terms of billing and metering. Apparent losses were attributed to a poor metering system characterised by use of non-functional meters and absence of a regulatory
policy on metering and billing. Management of the water supply system by the local authority
is fragmented between the departments responsible for water supply. This has resulted in
inefficient use of equipment and infrastructure provided for improving water management.
Controlling commercial losses was ranked first as a strategy to control NRW followed by
integrated management and reduction of physical water losses respectively. The
recommendations were to update the customer database and improve on metering. It was also
recommended that utilisation of available zonal meters and data loggers be done so that both
apparent and real losses are controlled. The study also suggested integrated management of
the water system so that departmental goals on water services are the same
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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