Water Demand Pattern Classification from Smart Meter Data

AbstractHigh frequency measurements of water demand at service connections are becoming more common as utilities install smart meter technology. The full range of use for these observations by water suppliers is only beginning to be realized. Potential applications include leak detection, improved demand forecasting, variable water pricing, and improved network operations. Here we develop an approach for the classification of demand patterns and apply this approach to a set of demands collected from smart meters within a single District Metered Area (DMA) of a municipal network. The goal of this work is to develop a robust procedure for classification of demands derived from smart metering and test this procedure on observational data. A fundamental aspect of many feature classification tools is representation of what are often complex and noisy data in a low dimensional feature space that captures the important attributes of the signal. In this work, we employ Gaussian Mixture Models (GMM's) as the basis set for representing demand patterns. GMM's provide a flexible approach to representing the temporal demand patterns with a relatively small number of parameters. The values of these parameters then serve as the feature set for multivariate classification. A data set of hourly demand readings spanning a six-month study period serve as the test case for analysis here. The smart meters record demands to both residential and commercial consumers. Results show that the GMM approach captures variations in the demand patterns between locations. To the first order, the identified patterns appear to be explained by the differences between residential and commercial consumers. The resulting groupings are compared to classifications made using total demand as the sole feature. The stability of the patterns over time is tested by independently clustering each month of data

Rapid Biodiversity Assessment of the Vava'u Archipelago, Kingdom of Tonga

Color Illustrations; mapsThis report presents the results and recommendations of a Biological Rapid Assessment Programme (BIORAP) carried out in the marine and terrestrial environments of the Vava’u Archipelago, Tonga, from 13 to 28 February 2014. Vava’u lies within the Polynesia−Micronesia Biodiversity Hotspot defined by Conservation International, which includes areas with significant biodiversity that are also highly threatene

Implementing community based seagrass monitoring in the Wellesley Island Group

A survey was commissioned in 2007 by the Carpentaria Land Council Aboriginal Corporation (CLCAC) and the North Australia Indigenous Land and Sea Management Alliance (NAILSMA) on behalf of the Traditional Owners of the Wellesley Island region who had raised concerns over unhealthy dugong and turtle reported from hunters. Traditional Owners felt that one possible cause of sick animals may have been as a result of seagrass dieback causing a shortage of food to the animals. To answer the concerns of the Traditional Owners, the Department of Primary Industries and Fisheries Marine Ecology Group was commissioned to survey the seagrass communities of the Wellesley Islands and to train Wellesley Islands Rangers on seagrass mapping techniques. This was the first time that seagrasses have been formally surveyed and mapped for 23 years in the Wellesley Islands. Seagrass communities were the dominant benthic habitat in intertidal and shallow subtidal areas with a high diversity (8 specie s) of coastal seagrass compared with other Gulf of Carpentaria locations. Evidence of heavy dugong feeding activity was observed on most intertidal seagrass meadows surveyed. The highest density of dugong feeding trails was observed in seagrass meadows dominated by Halodule uninervis (narrow leaf form) and/or Halophila ovalis. In addition, dugongs were regularly observed feeding in subtidal meadows from the helicopter during surveys. This survey was used to help fill gaps in knowledge and provide a baseline from which future monitoring could be conducted to identify research required to answer the uncertainties raised by the Traditional Owners, and to help with developing zoning plans for the management of their Sea Country

Dynamics of a tropical deepwater seagrass community during a major dredging campaign

A research and monitoring program was established to examine the potential impacts of a large scale capital dredging program on a tropical deepwater seagrass community between December 2005 and June 2008. The aims of the monitoring program were to fill gaps in our understanding of the dynamics of tropical deepwater seagrass habitats, their roles in fisheries productivity and their resilience and capacity for recovery from disturbance associated with dredging. While the dynamics of shallow coastal seagrasses in the region have been the subject of many studies little was previously known about the low density deepwater seagrass habitat that typified the study area. Results of the study revealed that these deepwater meadows had a high natural seasonal and inter-annual variability. Seasonality was substantially different to neighbouring shallow seagrass communities with a winter peak in abundance declining in spring before losing all above-ground biomass during summer months. Turbidity associated with dredging inhibited seagrass recruitment but there was evidence of seagrass recovery 12 months after the completion of dredging activity. Implications of the study for managing impacts to deepwater seagrass communities and differences in response to shallow coastal seagrasses are discussed

Implementing community based seagrass monitoring in the Wellesley Island Group

A survey was commissioned in 2007 by the Carpentaria Land Council Aboriginal Corporation (CLCAC) and the North Australia Indigenous Land and Sea Management Alliance (NAILSMA) on behalf of the Traditional Owners of the Wellesley Island region who had raised concerns over unhealthy dugong and turtle reported from hunters. Traditional Owners felt that one possible cause of sick animals may have been as a result of seagrass dieback causing a shortage of food to the animals. To answer the concerns of the Traditional Owners, the Department of Primary Industries and Fisheries Marine Ecology Group was commissioned to survey the seagrass communities of the Wellesley Islands and to train Wellesley Islands Rangers on seagrass mapping techniques. This was the first time that seagrasses have been formally surveyed and mapped for 23 years in the Wellesley Islands. Seagrass communities were the dominant benthic habitat in intertidal and shallow subtidal areas with a high diversity (8 specie s) of coastal seagrass compared with other Gulf of Carpentaria locations. Evidence of heavy dugong feeding activity was observed on most intertidal seagrass meadows surveyed. The highest density of dugong feeding trails was observed in seagrass meadows dominated by Halodule uninervis (narrow leaf form) and/or Halophila ovalis. In addition, dugongs were regularly observed feeding in subtidal meadows from the helicopter during surveys. This survey was used to help fill gaps in knowledge and provide a baseline from which future monitoring could be conducted to identify research required to answer the uncertainties raised by the Traditional Owners, and to help with developing zoning plans for the management of their Sea Country

Dynamics of a tropical deepwater seagrass community during a major dredging campaign

A research and monitoring program was established to examine the potential impacts of a large scale capital dredging program on a tropical deepwater seagrass community between December 2005 and June 2008. The aims of the monitoring program were to fill gaps in our understanding of the dynamics of tropical deepwater seagrass habitats, their roles in fisheries productivity and their resilience and capacity for recovery from disturbance associated with dredging. While the dynamics of shallow coastal seagrasses in the region have been the subject of many studies little was previously known about the low density deepwater seagrass habitat that typified the study area. Results of the study revealed that these deepwater meadows had a high natural seasonal and inter-annual variability. Seasonality was substantially different to neighbouring shallow seagrass communities with a winter peak in abundance declining in spring before losing all above-ground biomass during summer months. Turbidity associated with dredging inhibited seagrass recruitment but there was evidence of seagrass recovery 12 months after the completion of dredging activity. Implications of the study for managing impacts to deepwater seagrass communities and differences in response to shallow coastal seagrasses are discussed

Scaling of material properties for Yucca Mountain: literature review and numerical experiments on saturated hydraulic conductivity

A review of pertinent literature reveals techniques which may be practical for upscaling saturated hydraulic conductivity at Yucca Mountain: geometric mean, spatial averaging, inverse numerical modeling, renormalization, and a perturbation technique. Isotropic realizations of log hydraulic conductivity exhibiting various spatial correlation lengths are scaled from the point values to five discrete scales through these techniques. For the variances in log{sub 10} saturated hydraulic conductivity examined here, geometric mean, numerical inverse and renormalization adequately reproduce point scale fluxes across the modeled domains. Fastest particle velocities and dispersion measured on the point scale are not reproduced by the upscaled fields. Additional numerical experiments examine the utility of power law averaging on a geostatistical realization of a cross-section similar to the cross-sections that will be used in the 1995 groundwater travel time calculations. A literature review on scaling techniques for thermal and mechanical properties is included. 153 refs., 29 figs., 6 tabs

Development of the ASQoL: a quality of life instrument specific to ankylosing spondylitis

Background: Although disease-specific health status measures are available for ankylosing spondylitis (AS), no instrument exists for assessing quality of life (QoL) in the condition. Objective: To produce an AS-specific QoL measure that would be relevant and acceptable to respondents, valid, and reliable. Methods: The ASQoL employs the needs-based model of QoL and was developed in parallel in the UK and the Netherlands (NL). Content was derived from interviews with patients in each country. Face and content validity were assessed through patient field test interviews (UK and NL). A postal survey in the UK produced a more efficient version of the ASQoL, which was tested for scaling properties, reliability, internal consistency, and validity in a further postal survey in each country. Results: A 41 item questionnaire was derived from interview transcripts. Field testing interviews confirmed acceptability. Rasch analysis of data from the first survey (n=121) produced a 26 item questionnaire. Rasch analysis of data from the second survey (UK: n=164; NL: n=154) showed some item misfit, but showed that items formed a hierarchical order and were stable over time. Problematic items were removed giving an 18 item scale. Both language versions had excellent internal consistency (α=0.89–0.91), test-retest reliability (r(s)=0.92 UK and r(s)=0.91 NL), and validity. Conclusions: The ASQoL provides a valuable tool for assessing the impact of interventions for AS and for evaluating models of service delivery. It is well accepted by patients, taking about four minutes to complete, and has excellent scaling and psychometric properties