【作者】 高伟增；

【导师】 汪志农；

【作者基本信息】 西北农林科技大学 ， 农业电气化与自动化， 2008， 博士

【摘要】 灌区水量优化配置是实现合理抑制需求、有效增加供水、积极保护生态环境的有力手段和措施。因此改进灌区水量优化配置方法,对水资源在灌区和各用水部门间进行合理调配,实现有限水资源的经济、社会和生态环境综合效益最大,以及水质和水量的统一和协调具有重要的现实意义。研究遗传算法、自由搜索算法、神经网络算法等在灌区水量优化配置中的应用,是对灌区水量优化配置理论的有益补充。本文结合国家科技部863计划“数字渠系平台建设与精准用水管理决策应用”(2003AA209040)、西北农林科技大学科研专项“渠灌区时空配水管理通用模型库研究与开发”(04ZM070),以冯家山灌区为研究对象,进行了灌区优化配置若干理论和计算机管理决策系统研究。以提高水量优化配置效果为目的,深入研究了灌区水量优化配置的理论、优化配置模型,灌区用水管理评价、以及遗传算法和自由搜索算法对水量优化配置的应用。主要研究内容和取得的结论如下:(1)依据遗传算法理论,在配水求解中,摈弃传统的二进制编码,采用了和人们处理问题思路一致的十进制编码,用依次配水的顺序排列来表示各个个体的编码串,有效地提高了编码效率并降低了程序设计的难度。针对传统基因编码中基因不能很好反映渠道技术参数的问题,采用了复合基因编码技术,基因组编码中包括多个位码,既有表示渠道编号的位码,还有表示渠道流量、渠道配水优先级别等信息的位码。比以往用传统基因编码方法求解得到的优化信息更加完备,优化结果更加贴近实际。(2)针对遗传算法的某些局限性,本文采用自由搜索算法克服了传统基因编码方法容易陷入局部最优解的缺陷,扩大了算法的搜索空间,从而提高了基因序列的质量;同时由于对各个渠道流量调节采用了自由搜索算法,使各渠道的流量在其允许的范围内调节到最佳值,从而使各个渠道在同一时间关闭,不但减少了渠道弃水,而且在目前灌区的管理条件下还减少了人工管理的劳动时间,这对整个渠系水量调度具有很好的理论和现实意义。(3)灌区调度的目的在于将适时、适量的水分分配给各种作物,使得有限的水资源能产生最大的经济效益。对于水库灌区,若能将水量优化调度和土地资源以及人们不同优化目的有机地结合起来,将会使灌溉水资源真正得到有效合理的分配。本文构造了灌区不确定条件下多目标灌水定额模型并与渠系优化配水模型进行了实际验证。(4)针对目前综合评价中存在主观确定权重、最优值选取不准、评价函数不尽合理等问题,对灌区用水管理评价时采用主观法确定权重,多元相关分析法(Multivariate Correlation Analysis (MCA))客观调整权重,并预测参数的数值分布区间,最后用综合距离法(CP,也称折衷法)对指标进行综合评价。实例表明,该评价方法是科学的、可行的,是对综合评价理论有益的探索。(5)在市场经济条件下,无论是供水者还是需水者,利润对他们至关重要。充分拉动经济杠杆,对供水、需水及节水将具有重要的影响。本文从利益激励机制出发,给出了农业水价的合理范围,为科学制订水价提供了有益的参考。(6)基于灌区水量优化配置理论、方法、模型研究的基础上,采用面向对象模块化的设计方法,开发出了计算机管理决策系统。该系统能够实现灌区水情信息、渠系信息的查询、分析;能够根据实际情况制定出优化配水计划;对配水计划随时调整;也可对灌区用水计划管理进行综合评价。实例结果表明该系统具有很好的的通用性、实用性和可扩展性。更多还原

【Abstract】 Optimal water distribution in irrigation district(ID) is an important method and countermeasure for reasonably restraining the wate requirements, effectively increasing the water supply, and actively protecting the ecological environment etc. Therefore, improvement of the optimizing water distributing method have significances to distribute water for each user and realize the maximal benefits of the economy, society and ecological environment with the limited water resources and in harmony with the water quality and the water quantity. Discussing application of the genetic algorithms, Free search algorithms, and BP algorithms to the water distributiom in IDs are profitable for the water distributing theories.This research comes from the Ministry of Science and Technology’s Program“863”of“The platform construction of the digital canal system and the application of the decision-making for precise water use”(2003AA209040)and the scientific research of the Northwest A & F University of“The research and development of the common model base for distributing water in ID”(04ZM070), using the Fengjiashan ID as for the research object,carried out the research for the theory of optimal water distribution and decision-making system. Aim at improving the effect of water distributing, the paper research the water distributing intelligence method ,theory, optimal model and the evaluation of using water management in ID, the application of genetic algorithms and free search algorithms. The contents and conclusion of this paper include:(1) According as the genetic theory, it is essential to discarding the traditional binary system coding for solving water distribution. Being consistent with the way of thinking of the problem, decimal system is adopted. Using seriation of the canal for coding, it is enhancing the efficiency for coding and reducing the difficulty of programmer. As the traditional gene coding can’t reflecting the technique parameter of canal, the complex genecoding is introduced. The genome include several codes such as the number of canal, the discharge of canal, the level of canal etc. This method can give more scientific information for decision-making. It also make the result come close more to practice. (2) Considering GA sinking into the partial solution easily , free search algorithms is introduced. It extend the search space for algorithms, enhancing the quality of gene coding, adjusting the discharge of canal , making every canal close at the same time, decreasing the discarding water of canal, reducing the time of manual work. It have excellent theoretical and realistic effect on distributing water .(3) Only assigning the right amount water to every kind of farm crop at the right time can make the biggest profit for distributing water in ID. Putting the optimal purpose together with land and water resources will make water resources really getting optimal distribution. This article put forward a model to solve the question that how to select the irrigating quota on each application according to uncertain irrigation water use, uncertain climate and different optimal objectives. It has been put to use combining with the optimal cannal system model for distributing water.(4) Determining the index weight subjectively, confirming the data of index irrationality,evaluating the data illogicality is the limitation of comprehensive evaluation. Accordingly, MCA and Compromise Programming has been used on ID administrative levels. Determining the index weight by expert, adjusting the index weight by MCA, confirming the data space of the index value by statistics, and evaluating the irrigation district management by CP, it is it is more logical and reasonable for calculating the index weights and its data space, and evaluating the management in irrigation. The model is proved scientific and feasible in being applied to irrigation district. It have the beneficial quest on comprehensive evaluation theory.(5) under the market economy, whether the side of supplier or the user in water market, it is important for them to get profits. Pulling the economic lever well will have the important influence on water market. This text put forward a model to solve the question that how to evaluation of water cost for the whole interest according to inspiring motivation, giving the proper extension of the water price. It can provide scientific bases for the water pricing in ID.(6) Based on the research of water distributing method and models, developed computer management design-making system using modularization method. The system can realize the function of inquire, adjust the plan at any time according to actual circumstance and analysis the water information,evaluate the management in irrigation. practice expresses that the system is general ,practicable and expansible.更多还原