Functionality analysis of an urban water supply network after strong earthquakes

An urban water supply network(WSN)is a crucial lifeline system that helps to maintain the normal functioning of modern society.However,the hydraulic analysis of a significantly damaged WSN that suffers from pipe breaks or leaks remains challenging.In this paper,a probability-based framework is proposed to assess the functionality of WSNs in the aftermath of powerful earthquakes.The serviceability of the WSN is quantified by using a comprehensive index that considers nodal water flow and nodal pressure.This index includes a coefficient that reflects the relative importance of these two parameters.The demand reduction(DR)method,which reduces the water flow of nodes while preventing the negative pressure of nodes,is proposed.The difference between the negative pressure elimination(NPE)method and the DR method is discussed by using the example of a WSN in a medium-sized city in China.The functionality values of the WSN are 0.76 and 0.99 when nodal pressure and nodal demands are used respectively as the index of system serviceability at an intensity level that would pertain to an earthquake considered to occur at a maximum level.When the intensity of ground motion is as high as 0.4 g,the DR method requires fewer samples than the NPE method to obtain accurate results.The NPE method eliminates most of the pipes,which may be unrealistic.

Advanced Grey Relational Analysis Method and Its Application in Water Quality Evaluation of the Lake-type Wetland

Grey relational analysis is one of the most important methods in water quality evaluation system. As the traditional grey relational analysis has the defects of homogenization in static resolution ratio, small discrimination in correlation degree, and low precision in the weight of impact factors, this paper proposed an advanced grey relational analysis that used dynamic resolution ratio and comprehensive evaluation indicators. This method has been applied in the MIS software which monitors and evaluates the water quality in the lakes of the Four-Lake Basin. Compared with the traditional grey relational analysis and the cluster-factor analysis, this method could effectively enhance the reliability and accuracy of the results.

Use of Multi-criteria Decision Analysis Methods for Water Supply Problems： A Framework for Improved Rainwater Harvesting

Several conflicting objectives are considered in decision-making. MCDA （multi-criteria decision analysis） methods are developed to facilitate better decision making by decision-makers. Water supply problems are complex problems with multiple decision making and criteria. Hence, the use of multi-criteria decision analysis is very appropriate for solving these problems. Multi-criteria decision analysis can be divided into three main groups： value measurement models, goals, aspiration and reference level models and outranking models. The methods listed have been applied to water supply problems, especially in the evaluation of alternative water supply strategies. Each method has its advantages and limitations. A good alternative for concluding a better-suited method for water supply problems is to apply more than one method, either in combination to make use of the strengths of both methods, or in parallel to obtain a broader decision basis for the decision maker. Previous studies of MCDA in water supply planning have usually considered water supply networks with only one water service delivery. Advanced water supply sources with multiple water service delivery systems have been neglected. This is an on-going study in which analytical hierarchical multi-criteria decision analysis methods are proposed for solving water supply problems and a framework for improved rainwater harvesting systems will be developed.

Application of Argo Data in the Analysis of Water Masses in the Northwest Pacific Ocean

The temperature and salinity distributions, and the water mass structures in Northwest Pacific Ocean are studied using the temperature and salinity data obtained by Argo profiling floats. The T-S relation in this region indicates there exist 8 water masses, they are the North Pacific Tropical Surface Water （NPTSW）, North P, acific Subsurface Water （NPSSW）, North Pacific Intermediate Water （NPIW）, North Pacific Subtropical Water （NPSTW）, North Pacific Deep Water （NPDW） and Equatorial Surface Water （ESW）, and the South Pacific Subsurface Water （SPSSW） and South Pacific Intermediate Water （SPIW）.

Water Supply Networks as Cyber-physical Systems and Controllability Analysis

Cyber-physical systems (CPS) is a system of systems which consists of many subsystems that can stand alone in an individual manner and can be taken as a typical complex network. CPS can be applied in the critical infrastructures such as water supply networks, energy supply systems, and so on. In this paper, we analyze the structure of modern city water supply networks from the view of CPS theory. we use complex network theory to build an undirected and unweighted complex network model for the water supply networks to investigate the structural properties, and present the structure of the water supply networks and detect communities by a spectral analysis of the Laplacian matrix. Then, we analyze the structure and controllability of water supply networks by the structural controllability method. The results show the feasibility and effectiveness of the proposed complex network model. © 2014 Chinese Association of Automation.

Water Myths: The Illusion of Canada’s Endless Water Supply

This paper explores the common misconception that Canada has an infinite supply of freshwater. The true amount of water availability in Canada is explored, and the location of the majority of Canada’s water supply is described. As a consequence of a more precise assessment of Canada’s actual hydrologic situation the paper seeks to dash the dangerous myth of Canada’s water inexhaustibility, which is straining the country’s precious resource increasingly. Finally, this paper discusses the major threats to Canada’s water supply, which are from both external factors as well as its internal sociopolitical weakness. A solution to these problems is considered.

Decision Making for Capacity Expansion of Water Supply Systems

This study developed a systematic decision-making process for water supply capacity expansion using the analytic hierarchy process. The decision-making criteria were categorized into environmental, economic, technical and socio-cultural aspects. Capacity expansion of three water resources (Kpong, Weija and Teshie plants) of Accra-Tema Metropolitan Area (Ghana) was studied as a test case. The research resulted in the environmental criterion with the highest priority weight (52.4%), followed by the economic (30.6%), technical (11.3%) and socio-cultural criteria (5.8%). The overall analysis ranked the Kpong plant with a score of 36.1% followed by the Weija and Teshie plants with scores 33.8% and 30.2%, respectively.

Influential Factors of Water Productivity of Maize in Oasis of Arid Areas——A Case Study of Linze County

[Objective] The aim was to research influential factors of water productivity of maize in oasis in arid areas. [Method] In middle reach of Heihe River in Linze County of Zhangye City, maize, a major crop in irrigated area in the oasis, was studied and nine influential factors were chosen through grey relation analysis. [Result] According to grey relation analysis, top five factors influencing water produc- tivity of maize during 1995-2009 were as follows： applied quantity of chemical fertil- izers〉labour input〉seeds〉mulch amount〉pesticide amount, which indicated that controllable factors, instead of uncontrollable ones, dominate in influence of water productivity of maize in oasis in arid areas. [Conclusion] With water resource limited, investment of controllable factors in high-efficient agricultural production should be the major strategy to improve water productivity of maize in oasis of arid areas.

Gray comprehensive assessment and optimal selection of water consumption forecasting model

A comprehensive assessing method based on the principle of the gray system theory and gray relational grade analysis was put forward to optimize water consumption forecasting models. The method provides a better accuracy for the assessment and the optimal selection of the water consumption forecasting models. The results show that the forecasting model built on this comprehensive assessing method presents better self-adaptability and accuracy in forecasting.

Safety Evaluation of Water Environment Carrying Capacity of Five Cities in Ningxia Based on Ecological Footprint of Water Resources

[Objectives]To make safety evaluation of water environment carrying capacity of five cities in Ningxia based on ecological footprint of water resources.[Methods]With the help of the grey relational model,15 indicators were selected from the natural,economic,and social aspects,and the most influential factors in the three fields were selected.Based on the concept of ecological priority,the water resources carrying capacity of the five cities in Ningxia from 2010 to 2019 was calculated with the help of the water resources ecological footprint model.Then,the indicators of the water resources ecological footprint model were coupled with the existing indicators to establish a comprehensive evaluation indicator system.Finally,the changes of the water environment carrying capacity of the five cities in Ningxia were analyzed with the help of the principal component analysis(PCA).[Results]The ecological pressure of water resources and the ecological deficit of water resources in the five cities were relatively large.Specifically,Yinchuan City had the most obvious deficit of water resources but good carrying capacity;Zhongwei City had a large ecological deficit of water resources,poor carrying capacity,and the largest ecological pressure index of water resources;Guyuan City had low water resources ecological deficit,water resources ecological carrying capacity and water resources ecological pressure index.[Conclusions]Through the analysis of the coupling indicator system,it can be seen that the water environment carrying capacity of the five cities is in an upward trend,indicating that the water environment in each region tends to become better.

Optimization of Irrigation Water Allocation Framework Based on Genetic Algorithm Approach

In a world where excessive use and degradation of water resources are threatening the sustainability of livelihoods dependent on water and agriculture, increased food production will have to be done in the face of a changing climate and climate variability. There is a need to make optimal use of the available water resource to maximize productivity. Climate-smart irrigation is aimed at increasing per unit production and income from irrigated cropping systems without having negative impacts on the environment or other water users and uses. This paper developed a water allocation model using Genetic Algorithm to equitably allocation available water to the various sectors in Kano River Irrigation Scheme yielding an optimal as well as equitable water release with a 96.44% demand met. An average relative supply of 0.94 was obtained indicating the there was even supply of water to all the sectors. The model is robust and relatively easy to apply and can be employed by farm managers to achieve equity and optimal use of the available water resource.

Research on supplier evaluation and selection based on fuzzy hierarchy analysis and grey relational analysis

Considering the disadvantages of selecting evaluation index of supplier based on old purchase relation and in view of transformation of relation between manufacture and supplier under the dynamic, cooperative, competitive and quickly response environment, research on supplier selection evaluation was presented based on enterprise capability, cooperation degree and service level from the perspective of cooperative partnership and coordination, and the evaluation index system was established. A more objective and veracious supplier selection and evaluation method based on fuzzy analysis hierarchy process and grey relational analysis was developed, and then empirical research on electric equipment manufacturer was explored to analyze the supplier selection and evaluation.

Leaf Tissue Water Relations Are Associated with Drought-Induced Leaf Shedding in Tropical Montane Habitats

In tropical montane areas, water limitation is a common occurrence, and both pioneer and forests species experience water stress during the dry season. Adjustments of leaf area during periods of drought allow for the maintenance of the water supply and physiological functions of the remaining leaves. Here, we compared leaf blade water relations between pioneer and forest tree species. Leaf pressure-volume (P-V) curves were determined from samples taken prior to the dry season, to assess how leaves of the different species were adapted to prepare for and endure water deficits. The following parameters were calculated: osmotic potential at full (Ψπ(100)) and zero (Ψπ(0)) turgor, relative water content at zero turgor (RWC0), volumetric elastic modulus (&#949) as well as apoplasm (A) and symplasm (S) water content and their ratio (A/S). Although the pioneer and forest species occupied contrasting habitats, and both groups were clearly differentiated with respect to their water transport capability and water use efficiency, their leaf tissue water relations showed clear differences across species but not between the groups. Some species underwent leaf shedding and accumulated xylem embolisms during the dry season, and their leaves had high cell elasticity. Consequently, these species presented large cell volume changes with turgor loss. Conversely, species with rigid leaves were able to undergo lower leaf turgor with only small changes in cell volume during drought, which might aid to preserve leaf cell function, maintain water uptake, and consequently avoid accelerated leaf senescence and shedding during the dry season.

Research and application of GIS information system of Pipeline Network of Oil Field Water

Pipeline network of oil fi eld water is established on the basis of GIS geographic information and SCADA platform, and monitorthe running state of water supply system in oil fi eld mining area in real time through data acquisition, instrument measurement and control,wireless network, water quantity, water pressure and other on-line monitoring equipment. The water supply system is formed, and the informationof mass water supply system is analyzed and processed in a timely manner. The system manages the entire production, management and serviceprocesses of the water supply system in a dynamic manner in order to ensure water supply safety management, and realize the modernization,intelligence and information mode operation of the water supply system in the mining area.

RESEARCH ON MUNICIPAL WATER DEMANDS FORECAST

Based on the changing law of municipal water demand,a trigonometric function model for short-term water demand forecast is established using the time-series analysis approach.The method for forecasting water demand during holidays and under unexpected events is also presented.Meanwhile,a computer software is developed.Through actual application,this method performs well and has high accuracy,so it can be applied to the daily operation of a water distribution system and lay a foundation for on-line optimal operation.

用于农产品冷链物流需求预测的GRA-WHO-TCN组合模型

[目的/意义]为了解决冷链物流需求预测在数字化转型中存在特征提取不充分、数据非线性程度高和算法易陷入局部最优等问题,提出一种结合灰色关联分析(Grey Relational Analysis,GRA)、野马优化算法(Wild Horse Optimizer,WHO)和时序卷积网络(Temporal Convolutional Networks,TCN)的组合预测模型,旨在解决需求预测精度不高的问题,以实现农产品供应链智能化管理。[方法]首先运用GRA对农产品冷链物流相关指标进行关联度筛选;其次采用TCN充分考虑农产品供应链中社会经济数据及物流信息中的时序性特征,并使用WHO对TCN模型超参数进行寻优;最后运用优化的GRA-WHO-TCN模型对浙江省冷链物流需求进行预测。[结果和讨论]采用WHO的时序算法TCN模型能够有效提取多维度数据的时序特征和空间特征,具备较好的拟合效果。与GRALSTM、GRA-TCN和GRA-WHO-LSTM模型相比,GRA-WHO-TCN冷链物流需求预测模型具有较低的均方根误差值(11.3)和有效的相关系数(0.95),且预测2016—2020年浙江省农产品冷链物流需求量分别为2980、3046、2487、2645和2799万吨,能够实现对冷链物流需求较高的预测精度。[结论]提出的GRA-WHO-TCN模型具备良好的优化和预测能力,能够为数字经济背景下农产品供应链物资流、信息流发展提供科学预测依据和实际参考价值。

基于GRA-GRU的淮河流域水质预测研究

水质指标具有多元相关性、时序性和非线性的特点,为有效预测河流水质变化,针对水质数据存在缺失和异常的问题,提出基于灰色关联分析-门控循环单元(Grey Relational Analysis-Gated Recurrent Unit, GRA-GRU)的水质预测模型。以淮河流域水质数据为样本,使用线性插值修补缺失数据和剔除的异常数据。使用灰色关联分析计算不同水质指标间的相关性,选择高相关性的水质指标以确定输入变量,并使用门控循环单元(Gated Recurrent Unit, GRU)预测不同的水质指标。将GRA-GRU的预测结果与反向传播神经网络(Back Propagation Neural Network, BPNN)、循环神经网络(Recurrent Neural Network, RNN)、长短期记忆神经网络(Long Short Term Memory, LSTM)、GRU及灰色关联分析-长短期记忆神经网络(Grey Relational Analysis-Long Short Term Memory, GRA-LSTM)进行对比分析,结果显示GRA-GRU在不同水质指标预测上具有较好的适应性,可以有效降低预测误差。其中,与其他模型相比,GRA-GRU预测的化学需氧量在均方根误差上分别降低了3.617%、0.681%、0.478%、1.505%和0.471%。

基于一元线性回归模型的供水网络中水表读数虚高问题研究

为了定量研究供水网络中总表漏水程度和分表读数虚高程度,根据水量平衡分析法的原理,结合大数据分析技术,建立了一元线性回归方程,回归常数代表总表漏水量程度,回归系数代表分表读数虚高程度。通过针对2021年某高校供水管网的实证研究表明,总表日均漏水量为15.5958吨,分表读数虚高率为1.07%。该方法对供水管网漏损率的精准评估等问题的解决提供了新的思路和方法。

基于灰色关联度分析-极限学习机的低阻油层及水淹层测井识别——以渤海P区块馆陶组为例

历经近20的开发,渤海P区块进入高含水期,馆陶组发育的大量低阻油层与水淹层在测井曲线形态上差异不明显。为了精确进行水淹层识别以及水淹层等级划分,采用了机器学习算法。首先采用灰色关联度分析,筛选低阻油层和水淹层识别的敏感参数曲线;其次构建了极限学习机水淹层识别模型,对模型进行训练,获取最优参数。将其应用于实际资料处理,结果表明,基于灰色关联度分析极限学习机的低阻油层及水淹层测井识别方法对低阻油层与水淹层的预测精度较高,符合率达89.3%,远远优于未经过灰色关联度分析筛选的预测结果,具有实际应用价值。

河北省邢台市百泉泉域水资源供需平衡分析

为保证邢台市百泉泉域持续复涌,通过分析研究区域现状供、需水量情况,并预测该区域总需水量、地表水供水量、地下水供水量、非常规水和外调水量相关指标,定量分析水资源供需平衡。结果得出,上游水库的供水量可进一步置换泉域内生活、工业、农业用水及补充下游河道生态用水,各县(市、区)地下水开采量仍较高,而地表水实际利用量相对与地表水可供水量仍较低。建议该区域减少地下水开采量,科学合理分配利用地表水。