博尔塔拉河流域水域生态健康评估

以博尔塔拉河流域为研究区,参考流域生态健康评估综合指数法,构建水域生态系统健康评估指标体系,综合利用生境结构指标、水生生物指标和生态压力指标对水域生态系统健康进行评估。结果表明:博尔塔拉河流域水域生态健康等级为一般,限制因子为枯水期径流量和水资源开发利用强度;流域内博尔塔拉河上游区生态健康等级为良好,限制因子为枯水期径流量和鱼类物种多样性综合指数;中游区、下游区和大河沿子河区生态健康等级均为一般,限制因子分别为特有型或指示性物种保持率和水资源开发利用强度、鱼类物种多样性综合指数和水资源开发利用强度以及枯水期径流量和大型底栖动物多样性综合指数。山区水域生态健康等级高,平原地区等级偏低,上游生态健康等级高,中下游健康等级偏低。     

水资源足迹计算模型研究——以南京市为例

在生态足迹理论的基础上探讨了水资源足迹的概念。基于水资源生产力，推导出水资源足迹和水资源承载力的计算公式，用水资源赤字和水资源盈余来衡量水资源利用的可持续性。以南京市为例进行模型实证研究，计算了2003～2007年南京市水资源足迹和水资源承载力，结果表明南京市水资源足迹增长明显，水资源承载力总体平稳，赤字从2004—2007年呈指数增长趋势。实证研究表明模型结果可以在一定程度上衡量生产消费对水资源的影响。     

开都河-孔雀河流域水体污染承载力研究

通过大量实地调查取样、室内样品数据,采用水质计算模型和污染承载力模型计算分析开都河-孔雀河流域水污染承载能力,得出开都河-孔雀河流域不同水功能区、不同汛期水污染承载能力,从定量指标上反映各排污口允许排入开都河-孔雀河的污水数量,并提出具体措施和建议,对遏制流域水生态环境恶化,制定该地区水资源保护措施提供了有益的启发和借鉴.     

武威市水资源承载力评价与预测研究

水资源承载力分析计算和评价是干旱半干旱区寻求区域可持续发展道路的重要依据。探讨了水资源承载力的评价方法，采用模糊数学中的“隶属度”构建水资源承载力综合指数，并以灰色预测理论为指导，建立GM（1，1）模型对未来水资源承载力进行预测和精度分析。研究结果表明，1999-2006年武威市水资源处于可承载状态，可承载指数偏低，但呈逐步上升态势：2020年水资源承载力达到理想可承载状态。     

尼洋河流域水环境质量现状评价研究——基于模糊综合评价法

尼洋河流域水资源十分丰富,水能蕴藏量巨大,生态环境良好。随着西藏经济的发展,必将出现大规模开发利用水资源的趋势,探讨流域水资源和环境的现状及可持续发展具有十分重要的现实意义。本文对尼洋河流域基础资料的收集与整理,分析尼洋河流域的特点与现存的问题,根据收集的水质监测资料,分析了流域污染源概况和构成,以未进行水环境功能区划为前提,选择模糊综合评价法对尼洋河流域水环境质量进行现状评价,并对超标断面进行了原因分析,通过对2012年尼洋河流域14个监测断面监测成果的评价,得出尼洋河流域水质现状良好的结论,为以后的水功能区划分、水质目标的确定以及水环境功能区划分提供依据。     

多元线性回归和Bp神经网络预测水资源承载力--以济南市为例

水资源承载力的预测对发展地区经济具有重要意义，利用主成分分析方法对济南市水资源承载力变化的驱动力进行了分析，人口和GDP是影响水资源承载力变化的最主要的驱动因素。通过水资源承载变化驱动因子的多元线性回归模型和人工神经网络模型，分别预测出2010年和2020年济南市水资源的需求状况，并探讨了将线性和非线性相结合的方法用于水资源预测。     

流域生态需水量的研究——以德阳市绵远河为例

确定最小生态需水量,可实现水资源的可持续利用和流域水生态系统的稳定。以德阳市范围内的绵远河流域为研究区域,针对水闸修建和污染较为严重的特点,利用蒙大拿法和最枯月平均径流法分别计算河道基础生态需水量为9221.13×10~4m~3,5203.44×10~4m~3,进行对比分析选用蒙大拿法计算的结果。河道蒸发量为518.9m~3,针对绵远河上修建5座水闸计算河流渗漏量为2891.03×10~4m~3,并计算河流自净需水量为14016.00×10~4m~3。得出绵远河最小生态需水量为17425.03×10~4m~3。由计算结果可知,稀释污水消耗大量水资源,为了维持水生态健康必须重视污水的处理。     

城镇化进程中乐陵市水生态足迹和水资源承载力分析及预测

以水资源生态足迹和水资源承载力模型为基础,分析2010-2015年乐陵市水资源承载力,并对其进行预测。结果表明:(1)2010-2015年乐陵市总用水生态足迹呈逐年上升的趋势,农用水生态足迹比重最高,城镇生活用水的增加对生态用水挤压作用较强;(2)乐陵市水资源承载力呈波动中上升的态势,水资源承载力处于赤字状态;(3)水资源承载负载指数表明乐陵市水资源开发利用程度很高,潜力不大;(4)预测值逐年递增,但潜力较小,需借助外流域调水。通过对乐陵市水资源承载力状况进行评估与预测,旨在实现乐陵水资源可持续利用。     

水资源承载力研究进展

目前，水资源承载力研究主要集中于水资源承载力的各个方面，总体上还没有对其形成一个系统的认识。在总结水资源承载力研究历史和现状的基础上，阐述了水资源承载力的概念与内涵，对其研究方法及存在问题进行了论述，并预测了水资源承载力研究的发展趋势。     

大连市水资源承载力动态研究

区域水资源承载力是进行区域生态建设和确定社会经济发展规划的基础。介绍了基于主成分分析理论的区域水资源承载力评价方法,建立了反映大连市水资源承载力的指标评价系统,并对大连市2001—2008年的水资源承载力进行了定量分析。研究结果表明,近年来大连市水资源承载力逐年减弱,水资源已经成为制约大连市社会经济与生态环境协调发展的主要因素。针对这种现状,提出了大连市水资源可持续利用的若干对策。     

资源循环复杂物质流系统的Petri网建模方法研究

物质流分析是研究循环经济的重要方法,本文面向资源循环的流程制造企业,对不同复杂度的物质流系统进行了建模方法研究。首先对国内外在物质流领域的建模理论研究进行了综述,然后对物质流的特点和循环物质流的建模方法进行了分析,对基于投入产出表格的物质流分析方法、理论层面基于图论的物质流分析方法以及物质流分析软件进行了综述,最后重点探讨了Petri网建模与仿真工具在循环物质流分析中的建模方法,研究了不同类型Petri网在解决不同复杂度的物质流系统问题中的适用性,为物质流建模与仿真提供理论支撑。     

袋式除尘器结构优化设计与虚拟装配关键技术

针对袋式除尘器大型化后在结构轻质化、模块化结构的可靠装配和焊接变形控制等方面面临的诸多问题,开展了系统的研究,发展了不同结构类型袋式除尘器快速参数化建模、整体和局部联合计算、梁柱连接节点的简化设计、整体计算中复杂花板结构简化、非线性多约束结构优化等复杂关键技术,开发了袋式除尘器结构计算和优化设计软件;提出了基于世界树的实体层次系统结构建模框架,开发了大型模块化袋式除尘器虚拟装配软件;分析了主要结构焊接变形、应力和应变分布及变化规律,提出了反变形法消除焊接变形的控制方法,并开展了实验验证。     

新建水库初期磷氮变化的动态模拟研究

本文首先建立磷氮时空分布模型并确定模型参数的率定方法。文章模拟了新建清平水库建库初期磷氮变化情况,得出由不稳定到稳定的过程。水库磷氮时空变化的模拟结果表明,空间分布是从库尾到大坝浓度逐渐递砬,时间分布是一年中Ｐ,Ｎ浓度七月份最高,年初年末最低,其分布央线类似高斯分布。     

浅谈地理信息系统与排水模型软件的结合使用

随着城市排水系统信息化管理要求的提出与实践，城市排水管网地理信息系统和排水管网建模日益受到大家的重视。传统的排水管网建模方法耗时长、建模效率低。排水管网地理信息系统和排水管网模型结合使用的方式可缩短建模周期，提高排水管网建模的科学性，该研究对加快排水管网系统信息化建设有积极作用。     

Integrating Large Wood Jams into Hydraulic Models: Evaluating a Porous Plate Modeling Method

Large wood (LW) jams are key riverine habitat features that affect hydraulic processes and aquatic habitat. The hydraulic influence of LW jams is poorly understood due to the complexity of fluid dynamics around irregular, porous structures. Here we validated a method for two‐dimensional hydraulic modeling of porous LW jams using the open‐source modeling software Delft3D‐FLOW. We sampled 19 LW jams at three reaches across the Columbia River Basin in the United States. We used computer‐generated porous plates to represent LW jams in the modeling software and calibrated our modeling method by comparing model outputs to measured depths and velocities at validation points. We found that modeling outputs are error‐prone when LW jams are not represented. By representing LW jams as porous plates we reduced average velocity root mean square error (RMSE) values (i.e., improved model accuracy) by 42.8% and reduced average depth RMSE values by 5.2%. These differences impacted habitat suitability index modeling. We found a 15.1% increase in weighted useable area for juvenile steelhead at one test site when LW jams were simulated vs. when they were ignored. We investigated patterns in average RMSE improvements with varying jam size, bankfull obstruction, porosity, and structure type, and river complexity. We also identified research gaps related to field estimation of LW jam porosity and porous structure modeling methods.     

Implications of Conceptual Channel Representation on SWAT Streamflow and Sediment Modeling

Hydrologic modeling outputs are influenced by how a watershed system is represented. Channel routing is a typical example of the mathematical conceptualization of watershed landscape and processes in hydrologic modeling. We investigated the sensitivity of accuracy, equifinality, and uncertainty of Soil and Water Assessment Tool (SWAT) modeling to channel dimensions to demonstrate how a conceptual representation of a watershed system affects streamflow and sediment modeling. Results showed the amount of uncertainty and equifinality strongly responded to channel dimensions. On the other hand, the model performance did not significantly vary with the changes in the channel representation due to the degree of freedom allowed by the conceptual nature of hydrologic modeling in the parameter calibration. Such findings demonstrated good modeling performance statistics do not necessarily mean small output uncertainty, and partial improvements in the watershed representation may neither increase modeling accuracy nor reduce uncertainty. We also showed the equifinality and uncertainty of hydrologic modeling are case‐dependent rather than specific to models or regions, suggesting great caution should be used when attempting to transfer uncertainty analysis results to other modeling studies, especially for ungauged watersheds. Editor's note: This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.     

Modeling flood induced interdependencies among hydroelectricity generating infrastructures

This paper presents a new kind of integrated modeling method for simulating the vulnerability of a critical infrastructure for a hazard and the subsequent interdependencies among the interconnected infrastructures. The developed method has been applied to a case study of a network of hydroelectricity generating infrastructures, e.g., water storage concrete gravity dam, penstock, power plant and transformer substation. The modeling approach is based on the fragility curves development with Monte Carlo simulation based structural–hydraulic modeling, flood frequency analysis, stochastic Petri net (SPN) modeling, and Markov Chain analysis. A certain flood level probability can be predicted from flood frequency analysis, and the most probable damage condition for this hazard can be simulated from the developed fragility curves of the dam. Consequently, the resulting interactions among the adjacent infrastructures can be quantified with SPN analysis; corresponding Markov Chain analysis simulates the long term probability matrix of infrastructure failures. The obtained results are quite convincing to prove the novel contribution of this research to the field of infrastructure interdependency analysis which might serve as a decision making tool for flood related emergency response and management.     

基于仿真分析的复杂电子装备测试性预计技术研究

测试性是产品的一种设计特性,是伴随功能原理设计时赋予产品的一种固有属性。随着电子产品及设备的复杂和多样化,导致其故障诊断越来越困难,产品的测试性也逐渐得到生产和使用单位的重视。为尽早在研制阶段对产品的测试性水平进行评估,发现测试性设计的薄弱环节,首先对测试性仿真技术进行了简单介绍,之后详细阐述了基于TEAMS的测试性仿真方法,最后以某型柴油机系统为例,对其测试性指标进行预计,同时发现产品测试性设计上的薄弱环节,为产品的设计改进提供建议。     

Determination of Frequency for Remeasuring Ground and Vegetation Cover Factor Needed for Soil Erosion Modeling

Determining a remeasurement frequency of variables over time is required in monitoring environmental systems. This article demonstrates methods based on regression modeling and spatio-temporal variability to determine the time interval to remeasure the ground and vegetation cover factor on permanent plots for monitoring a soil erosion system. The spatio-temporal variability methods include use of historical data to predict semivariograms, modeling average temporal variability, and temporal interpolation by two-step kriging. The results show that for the cover factor, the relative errors of the prediction increase with an increased length of time interval between remeasurements when using the regression and semivariogram models. Given precision or accuracy requirements, appropriate time intervals can be determined. However, the remeasurement frequency also varies depending on the prediction interval time. As an alternative method, the range parameter of a semivariogram model can be used to quantify average temporal variability that approximates the maximum time interval between remeasurements. This method is simpler than regression and semivariogram modeling, but it requires a long-term dataset based on permanent plots. In addition, the temporal interpolation by two-step kriging is also used to determine the time interval. This method is applicable when remeasurements in time are not sufficient. If spatial and temporal remeasurements are sufficient, it can be expanded and applied to design spatial and temporal sampling simultaneously.     

正交化方法在水质模型参数确定中的应用

本文根据常微分方程参数反问题的数学理论，将正交化方法同有限差分法结合用于确定水质模型参数，并与正则化方法、最速下降法和共轭梯度法作了比较。其计算结果对比表明，正交化方法具有快速、简便、可靠的特点。更适合于水质模型参数的确定。