1,720,955 research outputs found
Optimization of Non-Revenue Water Management for Livingstone Town-Zambia: A Case Study of Lizuma Ward
No full textLivingstone Town has a water supply service coverage of 81 % and has been experiencing a high Non-Revenue Water (NRW) which stands at 43 % compared to the recommended value of 23 % suggested for developing countries. The high NRW poses a threat to the sustainability of service provision as more resources are used compared to the revenue generated. Despite the town having a water audit team in place, high non-revenue water is still a challenge. It is from this background that a study was carried out in Livingstone Town in the period from December 2015 to March 2016. The objective was to determine the trends of NRW from 2008 to 2015, establish factors contributing to NRW and estimate real losses using a hydraulic model (EPANET). The study focused on Lizuma Ward. Historical data maintained by the water utility on volume of water supplied and billed from 2008 to 2015 was analysed to determine the NRW trends for Livingstone Town. Determination of billing and meter errors was done through an independent meter reading exercise and meter testing respectively in Lizuma Ward. The results showed that yearly minimum and maximum NRW for Livingstone Town from 2008 to 2015 was 43 % and 49 % respectively with an average of 45 %. The minimum and maximum NRW for Lizuma Ward was 62 % and 68 % respectively with an average of 65 % of which 85 % were real losses and 15 % were apparent losses. Statistical analysis performed on the NRW for the eight year period gave a coefficient of variation of 0.04 which showed low variability of NRW from year to year. The Mann-Kendall trend tests indicated that there was no distinctive trend observed for NRW during the period under investigation as the computed p-value (0.898) was greater than significant level (0.05). The study also established that apparent losses included under billing (18 %), over registering of meters by 3.1 % and unauthorized consumption (85.1 %). Unauthorized consumption was deduced from total apparent losses, billing and meter errors. The accuracy of EPANET for estimating real losses was determined by performing a t-test on simulated and measured inflow to the ward. The test gave a p-value of 0.852 suggesting that there was no significant difference in the means. The t-tests was also performed on the simulated and measured pressure on five different location in Lizuma Ward distribution network which gave p-values of 0.842, 0.18, 0.131, 0.247 and 0.66 which were higher than significant level (0.05). Therefore there was no difference in the means of simulated and measured pressure hence suggesting that EPANET could be used to estimate real losses. The study concluded that there was no distinctive pattern observed for NRW trend. The main contributing factor to NRW were the real losses (85 %) while the unauthorized consumption (85%) was the major contributing factor to apparent water losses. EPANET can be used to estimate real losses. The study recommends that Southern Water and Sewerage Company should consider using EPANET in estimating the real losses, replace old pipes and water audit team should investigate unauthorized consumption
Optimization of non revenue water management for Livingstone Town-Zambia: A case study of Lizuma Ward.
No full textLivingstone Town has a water supply service coverage of 81% and has been experiencing a high Non-Revenue Water(NRW) which stands at 43%compared to the recommended value of 23% suggested for developing countries. The high NRW poses a threat to the sustainability of service provision as more resources are used compared to the revenue generated.Despite the town having a water audit team in place, high non-revenue water is still a challenge. It is from this background that a study was carried out in Livingstone Town in the periodfrom December 2015 to March 2016. The objective was to determine the trends of NRW from 2008 to 2015, establish factors contributing to NRW and estimate real losses using a hydraulic model (EPANET).The study focused on Lizuma Ward. Historical data maintained by the water utility on volume of water supplied and billed from 2008 to 2015 was analysed to determine the NRW trends for Livingstone Town.Determination of billing and meter errors was done through an independent meter reading exercise and meter testing respectively in Lizuma Ward. The results showed that yearly minimum and maximum NRW for Livingstone Town from 2008 to 2015 was 43% and 49% respectively with an average of 45%. The minimum and maximum NRW for Lizuma Ward was 62 % and 68% respectively with an average of 65% of which 85%were real losses and 15 % were apparent losses.Statistical analysis performed on the NRW for the eight year period gave a coefficient of variation of 0.04 which showed low variability of NRW from year to year.The Mann-Kendall trend tests indicated that there was no distinctive trend observed for NRW during the period under investigation as the computed p-value (0.898) was greater than significant level (0.05). The study also established that apparent losses included under billing (18 %), over registering of meters by 3.1 % and unauthorized consumption (85.1 %). Unauthorized consumption was deduced from total apparent losses, billing and meter errors. The accuracy ofEPANET for estimating real losses was determined by performing a t-test on simulated and measured inflow to the ward. The test gave a p-value of 0.852 suggesting that there was no significant difference in the means. The t-tests was also performed on the simulated and measured pressure on five different location in Lizuma Ward distribution network which gave p-values of 0.842, 0.18, 0.131, 0.247 and 0.66 which were higher than significant level (0.05). Therefore there was no difference in the means of simulated and measured pressure hence suggesting that EPANET could be used to estimate real losses. The study concluded that there was no distinctive pattern observed for NRW trend.The main contributing factor to NRW were the real losses (85 %) while the unauthorized consumption (85%) was the major contributing factor to apparent water losses. EPANET can be used to estimate real losses. The study recommends that Southern Water and Sewerage Companyshould consider using EPANET in estimating the real losses, replace old pipes and water audit team should investigate unauthorized consumption.,WaterNe
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
- …
