喷灌工程规划设计多方案选优的语言化与定量化相结合模糊综合评判数学模型

本文提出了喷灌工程规划设计多方案选优的语言化与定量化相结合的模糊综合评判数学模型,从而可得到比传统喷灌工程规划设计方案选优方法更为合理、满意的结果。     

基于GIS技术的小型水库规划方法

在小流域治理中，为了提高水库规划的精确度和速度，提出了基于GIS技术来实现小型水库规划的方法。主要是基于GIS技术的库客曲线的制作方法；小型水库规划的可视化。在GIS中，真实地形在计算机中的表达用数字高程模型(DEM)表示，水库规划的三维可视化环境的实现需利用0penGL技术。     

长时序海量土地利用时空数据统计优化方法

针对任意查询区域年度现状地类面积统计困难、长时序变更流量分析计算耗时等问题,提出基于时空变化图模型的统计优化方法。运用图的连通性原理,对查询统计区域内和边界处的要素实体进行分类,实现了时序快照统计优化算法,解决了任意查询区域时点现状统计困难的问题,提高了时序快照统计的效率。运用多商品流原理进行时空网络图约化性判定,实现了变更流量统计优化算法,减少了要素空间叠置分析次数,解决了长时序土地利用变化变更流量统计耗时问题,提高了统计的效率。最后,以2009—2012年琼海市土地利用数据为例,进一步验证优化算法的有效性和可行性。     

Determining crop-water production functions using yield–irrigation gradient algorithms

Crop-water production functions (CWPFs) are a useful tool for irrigation planning, but derivation of CWPFs by field experimentation is expensive, and traditional analytical techniques are not well suited to derivation of CWPFs. Physiologically based crop models provide a useful tool for simulation of agricultural experiments, but they have not been extensively applied to the task of CWPF determination. A new algorithm type based upon differential crop yield response to irrigation (“yield–irrigation gradients” [YIG]) is presented that uses these crop models to determine planning-level irrigation schedules and CWPFs. Three specific algorithms are developed within this type, varying in complexity, performance, and computational costs. Performance of the YIG methods is compared against a standard reference evapotranspiration method. In particular, the randomized iterative YIG (RIYIG) algorithm provides near-optimal results but at the highest computational costs of all the methods specified. All of the techniques presented have general applicability and are not limited to any one crop or location.     

Combining deliberative and computer-based methods for multi-objective land-use planning

This paper reports the outcomes of a deliberative workshop comparing land-use plans proposed by land-manager or domain experts with those derived using a computer-based decision support system (DSS). The DSS integrates four main components, a geographic information system, land-use systems simulation models, impact assessments and land-use planning tools. The land-use planning tools draw on the other components to generate and evaluate alternative patterns of land use and management. Since the land-use planning tools are based on multi-objective genetic algorithms (mGAs) it is possible to generate a range of alternative plans that define the structure of the trade-off between the objectives. The workshop tasked the delegates with specifying land-use plans that achieved the best compromise between two objectives known to be non-commensurable and conflicting. The nature of the best compromise was dependent on their individual perspectives. The delegates proposed allocations both as individuals and in researcher-facilitated sub-groups. The mGA allocations were then compared with those derived by delegates and were found to be broadly similar in performance. Differences in the range of allocations considered feasible were explained by the hard and soft constraints on allocations agreed between the delegates and articulated within the workshop process. The hypothesis that part of the difference in performance between the mGA and delegate allocations was due to the delegates blocking together fields with the same land use for convenience of management was proved. The analysis of the group allocations revealed that the decision-making process had failed to improve on the individual allocations. From these results it was concluded that there was a potential role for mGA based land-use planning tools in researching into, and deliberating on, the possible impacts of policy or other factors affecting land-use systems. It was further concluded that the tools should not be used in isolation since there was the need for stake-holder inputs to adequately define the range of feasible and practical land-use plans.     

湖南省节水灌溉分区与规划

将模糊聚类方法用于湖南省节水灌溉分区，建立了湖南省节水灌溉区划模型，将系统动力学的动态仿真原理用于节水灌溉发展规划，建立了节水灌溉发展规划的动态仿真模型。据此，提出了湖南省节水灌溉区划，并对各分区及全省“九五”期间节水浇灌发展作了详细规划。     

疏勒河灌区新垦盐碱地洗盐定额试

根据疏勒河灌区新垦盐碱地土壤含盐量高，需采用水平明沟排水冲洗改良的实际，开展了不同冲洗定额的洗盐效果试验研究，提出了排盐地区系数经验公式与冲洗定额对数函数计算公式。根据表层土壤含盐量高的特点，提出了以0~30cm土层作为冲洗改良盐碱地脱盐控制层的准则，并制定了相应的洗盐定额。     

A tool for community-based assessment of the implications of development on water security in hillside watersheds

Development and population growth in Latin American countries with steep slope farming are likely to further increase pressures on water and land resources. A methodology was developed for assessing water availability and use under different development pathways at a watershed scale to determine whether water security is a potential problem, and if so, under what conditions it is likely to occur. This methodology makes use of a GIS-based spatial water budget model for simulating stream water availability, water use and stream flow control on a daily basis at a watershed scale. Here, we analysed water availability under three plausible development scenarios for the 3246 ha Cabuyal River watershed in southwest Colombia in the year 2025: Corporate Farming (CF), Ecological Watershed (EW), and Business as Usual (BU). Simulated average river flows at the watershed outlet were, respectively, 874, 796 and 925 l s⁻¹ for the CF, EW and BU scenarios. The contribution of base flow to river flow (base flow index) was on average, 80.8, 85.6 and 77.9%, respectively, for the three scenarios. The watershed had the potential to meet the anticipated increase in water use under each explorative scenario. However, dams were necessary to store irrigation water in the CF scenario, otherwise over 60% of the available water would have been used during the dry season. Such a high figure raises concerns about effects on aquatic and riparian ecology, concentrations of potential contaminants, water reserves for especially low rainfall years, and the watershed resilience to meet temporarily higher water needs during the day. Analyses indicated that current water-use conflicts in the watershed can be resolved if irrigation water supply is separated from drinking water supply. This study helped reduce some of the complexity associated with the interdependencies between land and water resources, the impact of using them, and spatial linkages within the watershed. Results of this study can be used for teaching local stakeholders about basic landscape responses and helping multi-institutional alliances to become proactive and to guide development to the benefit of local communities.     

南方平原灌区渠道防渗工程规划方案决策分析

针对目前灌区防渗渠道规划的局限性，引入价值工程的概念，并根据南方平原地区灌区的特点，应用计算机模拟技术，通过对渠道的衬砌费用和节水量的模拟计算，得出更为切合实际的灌区防渗渠道投资效益评价指标，从而确定防渗工程的最优布局以及工程实施的先后顺序。     

基于改进A *算法的电动车能耗最优路径规划

提出一种基于改进A*算法的电动车能耗最优路径规划方法。根据车辆运行时的能耗,考虑能量损失与回收等因素,建立了运行能耗函数。设计了新的启发式能耗预估代价对A*算法进行改进,证明了所提出的启发式能耗预估代价满足可采纳性和一致性,确保改进的A*算法可获得能耗最优路径。针对电动车的里程焦虑问题,基于改进的A*算法,建立了根据车载电池的剩余电量、充电站位置、终点位置来寻找可达的能耗最小路径方法。仿真实验表明,提出的方法可以找到起点到终点的能耗最小路径,当车载电池能量不足时,可以找到经过充电站的可行最小能耗路径,减少里程焦虑,验证了所提方法的合理性和可行性。