Hybrid water treatment cost prediction model for raw water intake optimization

In order to reduce the total cost of a dual source drinking water treatment plant operation, a comprehensive hybrid prediction model was built to estimate the necessary chemicals dosage and pumping energy costs for alternative source selection scenarios. Correlations between the water quality parameters and the required treatment chemicals were estimated using historical data and the expected pH variations associated with each chemical addition, which was based on the Caldwell–Lawrence diagram. The pumping energy costs were also estimated using a data-driven approach that was based on historical plant data. The research has practical implications for water treatment operators seeking to minimize plant operational costs through selecting raw water intake volumes for their treatment plant based on multiple source options and offtake tower gate levels. Future research seeks to better link current and future water treatment dosage cost predictions directly to water quality measurements taken from vertical profiling systems.     

Contribution of rainfall vs. water management to Mediterranean wetland hydrology: Development of an interactive simulation tool to foster adaptation to climate variability

Mediterranean wetlands are increasingly managed to maintain their functions and services following modification in water allocation, embankment and climate change, calling for proactive and adaptive water management. In a first step, we used long-term monitoring of water levels in 37 adjacent embanked marshes in the Camargue as a repeated non-controlled experiment to build a hydrological model. Without information on water input/output by marsh users, we could nevertheless estimate evapotranspiration under flooding and dry conditions, and soil water coefficient. The model provided a high predictive accuracy (adjusted R² = 0.73–0.83) of monthly water levels when applied to an independent sample of 12 marshes. In a second step we developed an interactive decision-aid tool that allows users to visualize the impact of their management strategy (desired water level at a specific month) on subsequent water levels, and their consequence on different components of the ecosystem over a 10-yr period.     

基于LabVIEW和Web技术的水处理远程在线监控系统

随着水处理工艺的发展,相应的控制系统成为保证处理后水质、提高工作效率的关键。详细描述了在线与远程监控水处理控制系统的实现。利用LabVIEW虚拟仪器开发平台,通过SIMATIC.NET建立OPC服务器与西门子S7-300 PLC的连接;以SQL Server为后台数据库,实现数据采集与设备控制;并通过LabVIEW内嵌的Web工具将系统发布至互联网,实现了异地远程在线监控;采用GSM无线通信模块,利用手机短信方式查询系统实时数据,使系统在出现故障时能够自动通知高层管理人员。应用表明,该系统运行稳定可靠,能较好地实现水处理过程的集中和远程监控。     

Modelling domestic water demand: An agent based approach

The urban water system is a complex adaptive system consisting of technical, environmental and social components which interact with each other through time. As such, its investigation requires tools able to model the complete socio-technical system, complementing “infrastructure-centred” approaches. This paper presents a methodology for integrating two modelling tools, a social simulation model and an urban water management tool. An agent based model, the Urban Water Agents' Behaviour, is developed to simulate the domestic water users’ behaviour in response to water demand management measures and is then coupled to the Urban Water Optioneering Tool to calculate the evolution of domestic water demand by simulating the use of water appliances. The proposed methodology is tested using, as a case study, a major period of drought in Athens, Greece. Results suggest that the coupling of the two models provides new functionality for water demand management scenarios assessment by water regulators and companies.     

Development and application of an integrated ecological modelling framework to analyze the impact of wastewater discharges on the ecological water quality of rivers

Modelling is an effective tool to investigate the ecological state of water resources. In developing countries, the impact of sanitation infrastructures (e.g. wastewater treatment plants) is typically assessed considering the achievement of legal physicochemical quality standards, but ignoring the ecological water quality (EWQ) of the receiving river. In this paper, we developed a generic integrated ecological modelling framework quantifying the impact of wastewater discharges on the EWQ of the Cauca river (Colombia). The framework is flexible enough to be used in conjunction with different approaches/models and integrates a hydraulic and physicochemical water quality model with aquatic ecological models. Two types of ecological models were developed, habitat suitability models for selected macroinvertebrate groups and ecological assessment models based on a macroinvertebrate biotic index. Four pollution control scenarios were tested. It was found that the foreseen investments in sanitation infrastructure will lead to modest improvements of the EWQ, with an increase lower than six units of the ecological index BMWP-Colombia. Advanced investments, such as the collection and treatment of all wastewater produced by the cities of Cali, Yumbo and Palmira and upgrading of the treatment systems should be considered to achieve a good EWQ. The results show that the integration of ecological models in hydraulic and physicochemical water quality models (e.g. MIKE 11) has an added value for decision support in river management and water policy. The integration of models is a key aspect for the success in environmental decision making. The main limitation of this approach is the availability of physicochemical, hydraulic and biological data that are collected simultaneously. Therefore, a change in the river monitoring strategy towards collection of data which include simultaneous measurements of these variables is required.     

Paradigm shift to enhanced water supply planning through augmented grids,scarcity pricing and adaptive factory water: A system dynamics approach

This paper details a system dynamics model developed to simulate proposed changes to water governance through the integration of supply, demand and asset management processes. To effectively accomplish this, interconnected feedback loops in tariff structures, demand levels and financing capacity are included in the model design, representing the first comprehensive life-cycle modelling of potable water systems. A number of scenarios were applied to Australia's populated South-east Queensland region, demonstrating that introducing temporary drought pricing (i.e. progressive water prices set inverse with availability), in conjunction with supply augmentation through rain-independent sources, is capable of efficiently providing water security in the future. Modelling demonstrated that this alternative tariff structure reduced demand in scarcity periods thereby preserving supply, whilst revenues are maintained to build new water supply infrastructure. In addition to exploring alternative tariffs, the potential benefits of using adaptive pressure-retarded osmosis desalination plants for both potable water and power generation was explored. This operation of these plants for power production, when they would otherwise be idle, shows promise in reducing their net energy and carbon footprints. Stakeholders in industry, government and academia were engaged in model development and validation. The constructed model displays how water resource systems can be reorganised to cope with systemic change and uncertainty.     

A model integration framework for linking SWAT and MODFLOW

Assessment of long-term anthropogenic impacts on agro-ecosystems requires comprehensive modelling capabilities to simulate water interactions between the surface and groundwater domains. To address this need, a modelling framework, called “SWATmf”, was developed to link and integrate the Soil Water Assessment Tool (SWAT), a widely used surface watershed model with the MODFLOW, a groundwater model. The SWATmf is designed to serve as a project manager, builder, and model performance evaluator, and to facilitate dynamic interactions between surface and groundwater domains at the watershed scale, thus providing a platform for simulating surface and groundwater interactions. Using datasets from the Fort Cobb Reservoir experimental watershed (located in Oklahoma, USA), the SWATmf to facilitate linkage and dynamic simulation of SWAT and MODFLOW models. Simulated streamflow and groundwater levels generally agreed with observations trends showing that the SWATmf can be used for simulating surface and groundwater interactions.     

水工业领域广域网络监控系统的最新模式研究

本文从城市供水、排污水流程企业的厂站级和远程监控系统的现状出发，提出了构建最新的广域网络监控系统需要解决的几个关键问题，为创建新世纪的中国水工业领域综合自动化最新模式提出了一条切实可行的新思路。     

A two-step optimization procedure for assessing water constituent concentrations by hyperspectral remote sensing techniques: An application to the highly turbid Venice lagoon waters

Over the past few years, the increased spectral and spatial resolution of remote sensing equipment has promoted the investigation of new techniques for inland and coastal water monitoring. The availability of new high-resolution data has allowed improvements in models based on the radiative transfer theory for assessing optical water quality parameters. In this study, we fine-tuned a physical model for the highly turbid Venice lagoon waters and developed an inversion technique based on a two-step optimization procedure appropriate for hyperspectral data processing to retrieve water constituent concentrations from remote data. In the first step, the solution of a linearized analytical formulation of the radiative transfer equations was found. In the second step, this solution was used to provide the initial values in a non-linear least squares-based method. This effort represents a first step in the construction of a feasible and timely methodology for Venice lagoon water quality monitoring by remote sensing, especially in view of the existing experimental hyperspectral satellite (Hyperion) and the future missions such as PRISMA, EnMap and HyspIRI. The optical properties of the water constituents were assessed on the basis of sea/lagoon campaigns and data from the literature. The water light field was shaped by an analytical formulation of radiative transfer equations and the application of numerical simulations (Hydrolight software). Once the optical properties of the Venice lagoon bio-optical model were validated, the inverse procedure was applied to local radiometric spectra to retrieve concentrations of chlorophyll, colored dissolved organic matter and tripton. The inverse procedure was validated by comparing these concentrations with those measured in the laboratory from in situ water samples, then it was applied to airborne (CASI and MIVIS) and satellite (Hyperion) sensors to derive water constituent concentration maps. The consistent results encourage the use of this procedure using future missions satellite (PRISMA, EnMap and HyspIRI).     

GIS与水环境多源监测信息集成研究

以太湖流域的多源水环境监测信息为对象,以GIS和Visual Basic为工具,开发了太湖水环境监测信息管理系统,并阐述了该系统的组成及相应的功能,分析了其在水环境信息处理及表达等方面所具有的特点,通过对实际监测数据的处理和表达,证明了基于GIS的水环境监测信息管理系统快速、高效、实时等方面的优势。     

苏州城区活水联控联调系统架构设计

苏州城区河道纵横,闸、泵、堰等水利控制工程众多,目前主要依赖人工调度的模式,统筹兼顾难度较大,难以满足苏州城区水环境高质量目标实现所需的精准化调度要求。分析城区水利工程、监测设备及信息化建设现状,以畅流活水智慧调度应用开发为出发点,以监测数据为驱动,以模型为核心,以远控为手段,依托模型云,构建包括监测设备层、支撑平台层和业务应用层的苏州城区活水联控联调系统平台。平台建成后,利用物联感知系统代替人工观测,实现全智能一键化精准调度代替人工调度,充分发挥清水工程效益,通过精准调度可实现重点河道水体清澈,提升苏州市城区水利综合调度决策能力,完善苏州水利信息化建设布局。     

Solid modelling in a virtual reality environment

This paper presents a constraint-based methodology for intuitive and precise solid modelling in a virtual reality (VR) environment. A hierarchically structured and constraint-based data model is developed to support solid modelling in the VR environment. A constraint reasoning engine is also developed to automatically deduce allowable motions for precise constraint-based 3D manipulations. A prototype system of product modelling has been successfully developed, and experimental results demonstrate the advantage of precise solid modelling through constraint-based manipulation in virtual environments.     

Minimum volume ellipsoid classification model for contamination event detection in water distribution systems

The presented study features an event detection model alerting for contamination events in water distribution systems. The developed model comprises a minimum volume ellipsoid (MVE) classifier, detecting outlier measurements, and a following sequence analysis utilizing the MVE binary output, for the classification of events. The model is updated continuously and exploits a constantly growing data base. The MVE enables simultaneous analysis of the water quality parameters. The multivariate analysis explores the relations between water quality parameters and detects changes in their common patterns. The suggested model applied an un-supervised classification method, eliminates the need for simulated events examples in the classifier construction. In the absent of satisfying information regarding the influence of contamination event on the parameter measurements, eliminating the use of any assumption contributes to the model reliability and generality. The model was trained on a real water utility data, and tested on randomly simulated events that were superimposed on the original data base. The model showed high accuracy and detection ability compared to previous studies.     

Clustering Web pages based on their structure

Several techniques have been recently proposed to automatically generate Web wrappers, i.e., programs that extract data from HTML pages, and transform them into a more structured format, typically in XML. These techniques automatically induce a wrapper from a set of sample pages that share a common HTML template. An open issue, however, is how to collect suitable classes of sample pages to feed the wrapper inducer. Presently, the pages are chosen manually. In this paper, we tackle the problem of automatically discovering the main classes of pages offered by a site by exploring only a small yet representative portion of it. We propose a model to describe abstract structural features of HTML pages. Based on this model, we have developed an algorithm that accepts the URL of an entry point to a target Web site, visits a limited yet representative number of pages, and produces an accurate clustering of pages based on their structure. We have developed a prototype, which has been used to perform experiments on real-life Web sites.     

基于水体散射特性的SAR图像水体检测

基于SAR图像中水体后向散射系数服从Gamma分布的特点,提出了一种基于水体散射特性的自动化水体提取算法。研究重点包括:第一,利用高斯分布拟合地物后向散射系数,并结合改进的Gamma模型进行分析,确定最优阈值位置,构建优化准则,自适应迭代求解目标阈值。第二,引入含水体的目标块选择准则,剔除非目标块,对目标块运用所建模型获取阈值,取各目标块平均值作为全景图最优阈值,该过程大大缩短了运行时间,增加了阈值准确率,对SAR图像中水体的实时检测具有深刻意义。实验数据选用Radarsat-2获取的淮南地区单极化数据,实验结果表明该算法可以实现大幅图像中水体的快速、精确和自动化提取。     

基于物联网技术水资源环境监测仿真研究

研究对水资源环境进行监测的精度问题。针对传统的水资源监测系统难以自适应采集各种类型水资源数据信息和实时可靠地传输水监测数据的问题,特别是传统的监测算法具有较高的复杂性,参数设置需要大量的资源,为了解决上述问题,提出了一种多传感网络平台的水资源环境监测物联网技术。主要难点技术在于将监测区域分为若干个不同的分簇,每个分簇搜集各种类型的环境监测数据,且可依据监测需要设定不同类型的传感器;在监测区域内设置移动Agent节点,根据网络能耗建立实时二维定位表,采用Rosen梯度投影法选择最优路径,构建移动方案,搜集采集到的数据并转发给控制中心。仿真表明,提出的技术对水资源监测实现远程数据采集和传输,具有实时性和可靠性,且网络整体能耗较低。     

A Fuzzy Modelling Approach Using Hierarchical Neural Networks

A simple and effective fuzzy modelling approach is presented in this paper. A three-layer hierarchical clustering neural network is developed to build fuzzy rule-based models from numerical data. Differing from existing clustering-based methods, in this approach the structure identification of the fuzzy model is implemented on the basis of a class of sub-clusters created by a self-organising network instead of on raw data. By combined use of unsupervised and supervised learning, both structure identification and parameter optimisation of the fuzzy model can be carried out automatically. The simulation results show that the proposed method can provide good model structure for fuzzy modelling and has high computing efficiency.     

基于物联网的丹江口库区水质自动监测系统

丹江口库区水质自动监测系统采用物联网技术,并以混合型数据库和数据分发共享技术为核心的B/S模式为主。在点线面源的适当位置安装各种水质自动监测仪器、数据采集传输设备,通过多种有线或无线方式与监控中心的通信服务器相连,实现24 h在线的实时通信。以水质仪器为感知节点能将水质情况实时发送到监控中心,用以实现水质监测、水量调配等应用,以及各种更大规模的信息处理和共享。     

北京市南水北调某干渠自动输水系统设计

当前北京地区水资源短缺与过度开采问题比较严重,为解决这一难题,开发建设北京市南水北调某干渠自动输水系统。按照不同的业务需求设计,自动输水系统可分为监控、视频安防、水质监测、安全监测、通信及计算机网络等 5 个子系统,采用监控系统对压力和水量等参量进行采集、传输、存储,借助视频安防系统将图像采集及存储,利用通信及计算机网络系统确保信息传递的通达性和安全性,通过水质和安全监测系统确保供水安全,最终建立集动态监测、监控预警、远程控制、实时掌控为一体的联动输水系统。自动输水系统的建设,可实现北京市较为合理的水资源配置,加速地下水逐步置换,也进一步缓解水资源短缺与过度开采问题。     

鄱阳湖面积的卫星遥感估计及其与水位关系分析

鄱阳湖水位变幅巨大,近年来旱涝灾害严重,对其进行实时监测具有重要意义。MODIS遥感数据时间分辨率很高,在水体动态监测中具有明显优势。水体提取方法多种多样,在比较不同水体提取方法的基础上,最终选用改进的归一化水体指数(MNDWI)的方法进行鄱阳湖水体提取;利用2000~2010年40期MODIS数据分析了鄱阳湖这10 a的水面面积年际演变特征及季节性变化特征,同时结合同时期的水位数据,建立了鄱阳湖面积-水位关系的模型。与地形图量测结果的对比表明,遥感解译的鄱阳湖水体面积-水位关系与根据地形图分析建立的面积-水位关系具有较好的一致性。