scholarly journals Assessment of apparent losses due to meter inaccuracy – a comparative approach

Water SA ◽  
2019 ◽  
Vol 45 (2 April) ◽  
Author(s):  
Mthokozisi Ncube ◽  
Akpofure Taigbenu
Keyword(s):  
Empirical Method ◽  
Alternative Methods ◽  
Comparative Approach ◽  
Great Promise ◽  
Water Losses ◽  
Average Value ◽  
Quality Water ◽  
Development And Validation ◽  
Water Meters ◽  
Accuracy And Repeatability

The empirical method for the determination of apparent water losses, using the assessment of consumption patterns and the laboratory testing of water meters, is compared against alternative methods of comparative billing and meter change analyses for one of the largest water utilities in South Africa. Using the empirical method, apparent losses are estimated to have an average value of 12% of the billed volume with a range from 9.4% to 14.6% that is dependent on meter size ratios. This overlaps with the estimates, of 8%−10% for a utility with direct feed good quality water but high meter age (> 10 yr) and low accuracy, currently proposed in some studies and used by industry. The estimate from the comparative billing analysis method is 14% and it is sensitive to how the data is processed and analysed. The meter change method yielded an estimate of 4.7% for only a subset of the data. Both results of the alternative methods are in line with previous studies, with the comparative billing analysis performing better, but requiring further refinement for better accuracy and repeatability. The empirical method remains the gold standard in assessing apparent water losses but is undoubtedly very laborious, expensive and out of reach of the budget of many utilities. The development and validation of alternative methodologies therefore holds great promise but these are substantially reliant on comprehensive meter information and credible billing datasets which are rarely available in most utilities in Africa.

scholarly journals Development and Validation of an UHPLC-QqQ-MS Technique for Simultaneous Determination of Ten Bioactive Components in Fangji Huangqi Tang

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaoli Wang ◽  
Xiao Liu ◽  
Tingting Zhu ◽  
Baochang Cai
Keyword(s):  
Simultaneous Determination ◽  
Gradient Elution ◽  
Chromatography Method ◽  
Atractylenolide I ◽  
Ultrahigh Performance Liquid Chromatography ◽  
Liquid Chromatography Method ◽  
Development And Validation ◽  
Accuracy And Repeatability ◽  
Atractylenolide Iii

The aim of this study is to develop an ultrahigh performance liquid chromatography method coupled with triple quadrupole mass spectrometry for simultaneous determination of tetrandrine, fangchinoline, atractylenolide I, atractylenolide III, calycosin-7-O-β-D-glucoside, glycyrrhizin, liquiritin, isoliquiritin, liquiritigenin, and isoliquiritigenin in Fangji Huangqi Tang (FHT). The chromatographic separation was performed on a reversed-C18column, eluted with a mixture of 0.1% acetic acid and acetonitrile at 0.4 mL/min. The separation of these ten compounds was achieved by linear gradient elution. The method was strictly validated with respect to specificity, precision, accuracy, and repeatability. All the compounds showed good linearities (r≥0.999). The LOQs of the ten components were 0.36, 0.18, 0.09, 0.43, 0.02, 1.89, 0.26, 0.18, 0.61, and 0.48 ng/mL for tetrandrine, fangchinoline, atractylenolide I, atractylenolide III, calycosin-7-O-β-D-glucoside, glycyrrhizin, liquiritin, isoliquiritin, liquiritigenin, and isoliquiritigenin, respectively. The LODs of the ten components were 0.11, 0.05, 0.03, 0.13, 0.01, 0.57, 0.08, 0.05, 0.18, and 0.14 ng/mL for tetrandrine, fangchinoline, atractylenolide I, atractylenolide III, calycosin-7-O-β-D-glucoside, glycyrrhizin, liquiritin, isoliquiritin, liquiritigenin, and isoliquiritigenin, respectively. The method was proven to be specific and reliable, which would provide a meaningful basis for the quality control and evaluation of FHT during its clinical application.

scholarly journals Evolution of speech rhythm: a cross-species perspective

2019 ◽  
Author(s):  
Andrea Ravignani ◽  
Simone Dalla Bella ◽  
Simone Falk ◽  
Chris Kello ◽  
Florencia Noriega ◽  
...  
Keyword(s):  
Motor Coordination ◽  
Temporal Structure ◽  
Alternative Methods ◽  
Comparative Approach ◽  
Speech Rhythm ◽  
Human Speech ◽  
Origin And Evolution ◽  
Behavioral Traits ◽  
Evolution Of Speech ◽  
Animal Vocalizations

Cognition and communication, at the core of human speech rhythm, do not leave a fossil record. However, if the purpose is to understand the origin and evolution of speech rhythm, alternative methods are available. A powerful tool is comparative approach: studying the presence or absence of cognitive/behavioral traits in other species, drawing conclusions on which traits are shared between species, and which are recent human inventions. Here we apply this approach to traits related to human speech rhythm. Many species exhibit temporal structure in their vocalizations but little is known about the range of rhythmic structures perceived and produced, their biological and developmental bases, and communicative functions. We review the literatures on human and non-human studies of rhythm in speech and animal vocalizations to survey similarities and differences. We report important links between vocal perception and motor coordination, and the differentiation of rhythm based on hierarchical temporal structure. We extend this review to quantitative techniques useful for computing rhythmic structure in acoustic sequences and hence facilitating cross-species research. While still far from a full comparative cross-species perspective of speech rhythm, we are closer to fitting missing pieces of the puzzle.

scholarly journals Evolution of speech rhythm: a cross-species perspective

2019 ◽  
Author(s):  
Andrea Ravignani ◽  
Simone Dalla Bella ◽  
Simone Falk ◽  
Chris Kello ◽  
Florencia Noriega ◽  
...  
Keyword(s):  
Motor Coordination ◽  
Temporal Structure ◽  
Alternative Methods ◽  
Comparative Approach ◽  
Speech Rhythm ◽  
Human Speech ◽  
Origin And Evolution ◽  
Behavioral Traits ◽  
Evolution Of Speech ◽  
Animal Vocalizations

Cognition and communication, at the core of human speech rhythm, do not leave a fossil record. However, if the purpose is to understand the origin and evolution of speech rhythm, alternative methods are available. A powerful tool is comparative approach: studying the presence or absence of cognitive/behavioral traits in other species, drawing conclusions on which traits are shared between species, and which are recent human inventions. Here we apply this approach to traits related to human speech rhythm. Many species exhibit temporal structure in their vocalizations but little is known about the range of rhythmic structures perceived and produced, their biological and developmental bases, and communicative functions. We review the literatures on human and non-human studies of rhythm in speech and animal vocalizations to survey similarities and differences. We report important links between vocal perception and motor coordination, and the differentiation of rhythm based on hierarchical temporal structure. We extend this review to quantitative techniques useful for computing rhythmic structure in acoustic sequences and hence facilitating cross-species research. While still far from a full comparative cross-species perspective of speech rhythm, we are closer to fitting missing pieces of the puzzle.

scholarly journals Water Sensitive Landscape Case Study: Public Open Green Spaces in Naser City, Egypt

2016 ◽  
Vol 9 (3) ◽  
pp. 66-83
Author(s):  
Noha Ahmed Abd El Aziz
Keyword(s):  
Irrigation System ◽  
Green Spaces ◽  
Low Flow ◽  
Treated Wastewater ◽  
Arid Environments ◽  
Maintenance Schedule ◽  
City District ◽  
Quality Water ◽  
Water Meters ◽  
Water Quality And Quantity

Abstract The purpose of this paper is to reveal measures to lower water demand and consumption of public green spaces in arid environments such as Cairo city while maintaining a pleasant appearance. The Water Sensitive Urban Design approach is adopted to formulate a checklist in order to evaluate the extent to which public green spaces in “Naser City” district, participate in preserving water quality and quantity. After analyzing six case studies, the study concluded that the main problems are using high-quality water to irrigate green spaces, and the gardeners’ reckless irrigation and maintenance techniques. Short term solutions were proposed, such as utilizing low flow irrigation system, minimizing the lawn areas, integrating water meters, using mulching and incorporating a competent maintenance schedule. Long term solutions mainly focused on replacing potable water with treated wastewater, which is estimated to cover irrigation needs for all green areas in the district.

scholarly journals Analysis of Water Losses and Assessment of Initiatives Aimed at Their Reduction in Selected Water Supply Systems

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1037 ◽  
Author(s):  
Ewa Ociepa ◽  
Maciej Mrowiec ◽  
Iwona Deska
Keyword(s):  
Water Supply ◽  
Water Loss ◽  
Distribution Systems ◽  
International Standards ◽  
Water Supply Systems ◽  
Water Losses ◽  
Supply Networks ◽  
Water Supply Networks ◽  
Loss Index ◽  
Water Meters

This paper presents the analysis and assessment of water losses in water distribution systems of three water supply companies operating water supply networks in the area of effect of underground mining. The analysis of water losses was conducted based on numerous indices allowing for obtaining objective information on the condition of the water supply system. The method of the analysis of percentage water loss index was extended by the methods of determination of losses according to the International Water Association. The results of the analysis lead to the conclusion that with regular actions, the companies have reduced water losses in recent years to a level considered to be good compared to national data and average compared to international standards. The value of the failure intensity index for all companies in 2011 was over 1.0 while currently it is about 0.5. The decrease in Non-Revenue Water basic loss index (NRWB) from more than 20% for all analysed companies in 2008 to a few percent in 2017 and the decrease in Infrastructure Leakage Index (ILI) for companies A and C to less than 2.0 are evidence of the good condition of the network. This is also confirmed by the unit water loss index per capita, with its value in 2017 being 9.1 dm3/(inhabitant day) for company A, 11 dm3/(inhabitant·day) for B and 7.4 dm3/(inhabitant·day) for C. The several years of analysis and evaluation of numerous indices of water loss presented in the paper reveals the effectiveness of the adopted strategies of reducing leakages in the distribution system. It should be emphasized that the analysed companies have been involved in comprehensive initiatives aimed at reducing water leakages, resulting in a substantial reduction in water losses. GIS monitoring systems and databases are particularly helpful in reducing water losses. The basis of the activities is monitoring of flow and pressure in water supply networks and active leakage control. Network zoning with simultaneous observation of minimum night-time flows allows for preliminary location of the failure. Equipping companies with special leakage detection devices such as geophones, stethophones or correlators enables quick detection of leakages. The next step is to replace water meters with more and more accurate ones and to implement radio reading of water meters. All analysed companies perform systematic replacement of old steel and cast iron pipes which cause a large number of leakages that are often difficult to identify, thus leading to water losses.

The ECVAM Workshops: A Critical Assessment of their Impact on the Development, Validation and Acceptance of Alternative Methods

2002 ◽  
Vol 30 (2_suppl) ◽  
pp. 151-165 ◽  
Author(s):  
Robert D. Combes
Keyword(s):  
State Of The Art ◽  
Substantial Effect ◽  
Alternative Methods ◽  
Current Status ◽  
In Vitro Tests ◽  
Regulatory Requirements ◽  
Safety Testing ◽  
Task Forces ◽  
Development And Validation

ECVAM initiated its workshop programme in 1994, to enable it to become well informed about the state of the art of non-animal test development and validation, and about the possible incorporation of alternatives into regulatory requirements for safety testing. Fifty-one such workshops had been held on specific topics, up to 2002. In these workshops, the current status of in vitro tests and their potential uses were reviewed and recommendations were made as to the best ways forward to progress and enhance the use of in vitro methods. Reports for 46 of these workshops have been published in ATLA. Most of the workshops focused on in vitro replacement methods, although an increasing number have dealt with reduction and refinement. The recommendations in the ECVAM workshops have been progressed further by: a) the formation of ECVAM task forces; b) the organisation of further workshops; c) the activities of scientific committees; d) the provision of earmarked research funding; and e) the conduct of validation studies. Examples of each of these activities are discussed. Some individual workshops are covered in more detail, and several recommendations that have so far not been acted on are also considered. The workshops and their reports have had a substantial effect on the development and implementation of alternative methods, and have been a major factor in contributing to the success of the first nine years of ECVAM's existence. It is strongly recommended that ECVAM continues to organise workshops and to publish their findings, and suggestions are made for topics for future workshops.

Development and validation of an enhanced semi-empirical method for estimation of aerodynamic characteristics of light, propeller-driven airplanes

2016 ◽  
Vol 232 (4) ◽  
pp. 638-648 ◽  
Author(s):  
M Rostami ◽  
SA Bagherzadeh
Keyword(s):  
Wind Tunnel Test ◽  
Aerodynamic Characteristics ◽  
Empirical Method ◽  
General Aviation ◽  
Design Data ◽  
Stability And Control ◽  
Control Derivatives ◽  
Development And Validation ◽  
Semi Empirical ◽  
And Control

This study is intended to introduce an enhanced semi-empirical method for estimation of longitudinal and lateral-directional stability and control derivatives in the preliminary design phase of light airplanes. Specialised for light, single or twin propeller-driven airplanes, available state-of-the-art analytical procedures and design data compendia are combined and modified in a unique compatible method, and automated in NAMAYEH software. In the present study, modified procedures and the software structure are presented. Afterwards, the proposed method is applied to a four-place, low wing, single-engine, propeller-driven general aviation airplane. In order to validate the proposed method, the estimated aerodynamic characteristics are compared with the wind tunnel test data as well as DATCOM and VLM-based method estimations. The results indicate that the proposed method is able to predict the aerodynamic characteristics in an acceptable range of accuracy from zero-lift to stall conditions in all configurations.

scholarly journals Development of Science E-Flipbook Integrated Illegal Sand Mining on River Basin to Improve Environmental Care Attitude

2020 ◽  
Vol 3 (1) ◽  
pp. 26
Author(s):  
Shobhi Al-Ghifari Azhary ◽  
I Gusti Putu Suryadarma ◽  
Puspa Indah Devitasari ◽  
Kuswanto Kuswanto
Keyword(s):  
River Basin ◽  
Junior High School ◽  
Science Learning ◽  
Descriptive Analysis ◽  
Sand Mining ◽  
Average Value ◽  
Environmental Care ◽  
Learning Content ◽  
Content Expert ◽  
Development And Validation

The aim of this research is to produce a valid e-flipbook on science learning content for water pollution that integrated with illegal sand mining activities in a river basin to enhance environmental care attitude. The research method used was research and development with ADDIE models that are limited to the developing stage. The research sample consisted of 20 seventh grade students of junior high school. The average validation resulted by media expert is 3,5 and content expert is 3,6 with very good category, the result of validation by science teacher is on average 3,6 with very good category and peer reviewer obtained an average value of 3,7 with very good category, the results of validation by 20 students obtained an average value of 3,7 with very good categories. Research data were analyzed and interpreted using descriptive analysis. Based on the results of development and validation, this e-flipbook can be concluded valid and can be applied in learning. This research is important because it uses technology and raises issues about environmental problems

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