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1.
灌区运行水平综合评价是灌区投资决策的首要依据,也是推进灌区现代化建设的基础。为提高灌区运行水平综合评价精度,以四川省7个典型灌区为例进行了实证研究。根据系统性、科学性及实用性等原则建立了灌区运行水平综合评价指标体系,运用博弈论法将G1法确定的主观赋权与改进熵权法确定的客观赋权进行综合赋权,基于加权秩和比法(加权RSR法)构建了灌区运行水平综合评价模型,结合四川省典型灌区的实际情况对7个典型灌区进行评估,基于加权秩和比法评价模型的结果表明:四川省7个典型灌区运行水平(加权RSR估计值)由高到低依次为金堂县团结水库灌区(0.729 6)、安州区一大渠灌区(0.680 7)、乐山市高中水库灌区(0.646 1)、南充市磨尔滩水库灌区(0.623 3)、夹江县东风堰灌区(0.599 2)、阆中市石滩水库灌区(0.574 4)和凉山州西礼灌区(0.541 8),模型评价结果与灌区实际运行水平基本一致。因此可为灌区运行水平综合评价提供一种新的途径。 相似文献
2.
为解决轻小型喷灌机组喷洒运行、效果检测和能耗分析中涉及到的技术指标综合评价问题，提出采用主成分分析法对喷灌机组进行综合评价的数学模型。总结了喷灌机组喷灌面积、喷灌强度、组合均匀度和能耗等多种单技术评价指标，增加了综合评价的过程。选取评价其技术特性的5个单重要指标，应用所建的评价模型对4套喷灌机组进行综合评价。结果表明：前2个主成分包含了5个指标全部信息的98.75%，最终利用综合主成分公式得到4套喷灌机组综合技术评价指标的排名。该模型可对喷灌机组技术指标进行综合评价，也可为喷灌机组的设计优劣提供评判依据。 相似文献
3.
为了科学评判灌区的综合应用,实现灌区的利润最大化,农民纯收入大幅提高,需要对灌区的整体运行情况进行综合效益评价研究.首先将德尔菲法和模糊分析法相结合,引入信息熵进而计算获得的结构熵权法对评估指标进行综合赋权,赋权值后再引入密切值决策法对大型灌区洛惠渠灌区2007—2012年的运行状况进行综合评价研究.结果表明:洛惠渠灌区在2007—2012年的密切值分别为2.719 2,2.205 1,1.311 7,0.485 5,0.188 8,0.000 0,运行状况越来越好;相隔年数密切差值为0.514 2,0.893 3,0.826 3,0.296 7,0.188 8,运行状况趋向稳定.基于结构熵权—密切值法的评价研究结果与拉开档次—集对分析法、灰色关联理论—TOPSOS法的评价结果都大体相同,都伴随着时间的推移,灌区运行的状况越来越好,且更加精确,这也符合洛惠渠灌区的实际发展状况.该方法计算简明,可靠性高. 相似文献
4.
加强灌区建筑物管理是实现灌区可持续发展的有效途径。将商业财务领域中的资产管理方法引入到灌溉系统管理中来,根据其基本原理建立了灌区资产综合评价体系,通过层次分析法和熵值法确定指标权重,对灌区资产的运行状况、水力性能、重要度等类别的不同指标进行综合评价,其评价结果可以作为决策支持信息确定资产更新改造的优先性,制定中长期的投资策略。以湖北省漳河灌区四干渠和二干渠为例,对其干渠沿线资产(水闸、涵管、渡槽、桥梁、泵站等5类)进行评价和对比分析。评价结果与灌区实际运行、管理情况基本一致。 相似文献
5.
根据干旱半干旱地区农灌区水资源利用现状及特点,以西辽河平原农灌区为例,建立农灌区综合评价模型,采用层次分析法确定指标权重,并利用灰色关联法对灌区运行状况进行评价。通过对西辽河平原农灌区现状水平的评价,根据各农灌区关联度的大小对灌区进行分类,其结果与实际调查情况基本一致,具有一定的可信度,为干旱半干旱地区农灌区水资源开发利用及节水灌溉规划提供科学依据。 相似文献
6.
灌区运行水平综合评价研究进展 总被引：1，自引：0，他引：1
灌区运行水平综合评价是实现灌区科学与可持续发展管理的基础,也是灌区续建配套及节水改造投资的重要决策依据。介绍了灌区运行水平综合评价指标体系的构建,研究了指标权重不同的确定方法;对灌区运行水平综合评价的现有20多种评价方法进行了比较,明确了其优缺点及评价结果的精度;提出未来灌区运行水平综合评价指标体系应更多考虑反映生态化、信息化、智能化和可持续发展的技术指标,构建基于人水和谐的现代化美丽灌区评价指标体系和智能化灌区运行水平综合评价基础信息采集系统;要基于新的数学方法和模型建立灌区运行水平综合评价新方法,结合3S等现代信息技术开发现代化灌区运行水平综合评价平台,提高评价模型的可操作性与评价结果的精确性,进而更科学的指导灌区现代化建设。 相似文献
7.
江西省大型灌区运行状况综合评价 总被引：1，自引：0，他引：1
柯劲松 《中国农村水利水电》2008,(10):64-68
建立了一套适合我国大型灌区综合评价的指标,运用层次分析法（主观赋权法）和熵值法（客观赋权法）相结合确定指标综合权重。应用近似理想点法和灰色关联聚类法分别从客观和主观两个方面对江西省13个大型灌区进行了综合评价,两种评价结果基本一致。通过对评价结果的对比分析,讨论了两种方法的优缺点,并为各灌区发现差距, 改进运行管理水平提供了方向。 相似文献
8.
大型灌区现状和节水改造紧迫程度评价 总被引：7，自引：1，他引：6
为了对大型灌区现状和节水改造紧迫程度进行评价，在系统科学地评价灌区现状水平的基础上，通过分析研究表征灌区现状水平的关键指标，并对其值进行横比处理，采用权重综合评价方法对灌区进行综合评价。通过对灌区现状的评价，得出不同灌区节水改造的紧迫程度。通过实例分析，说明了灌区现状评价的实际应用的可能性。 相似文献
9.
对比分析了对大型灌区的常用评价方法,指出这些方法存在的主要缺点是评价中各指标权重的确定易受人们主观因素的影响.改进突变理论避免了评价各指标权重的确定问题,从而相对减少了人们主观因素的影响.对突变理论综合评价方法进行了改进,通过调整突变理论评价综合值的方法,克服了综合评价值过高和过于接近的问题,提高了其评价结果的分辨水平.将改进突变理论综合评价方法运用于大型灌区运行状况综合评价中,以陕西省大型自流渠灌区洛惠渠为实例进行验证,洛惠渠灌区在2009,2010,2011,2012年的评价值分别为0.060 5,0.265 7,0.549 1,0.660 1,运行状况等级分别为中等,良好,良好,良好.其评价结果与改进TOPSIS法的结果基本一致,都随着时间的推移,洛惠渠灌区评价级别从中等逐渐变为良好,运行状况越来越好,这也符合洛惠渠灌区的客观实际和发展规律,且该方法计算简单、可靠性高,可为大型灌区运行状况综合评价提供一种新方法. 相似文献
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综合考虑节水农业的特点及其可能对地区社会、经济和生态环境多方面的影响,按照指标筛选、降维、综合效益评价的思路提出了基于多目标评价和基于Topsis方法的节水农业综合效益评价方法。以黑龙江和平灌区近5年的节水改造、灌溉用水、作物种植、气象等资料,分析了节水农业综合效益评价的影响因素,选取了社会、经济和环境3个二级指标和22个三级指标,建立了节水农业综合效益评价指标体系。采用主成分分析法对指标进行降维,提高了评价指标体系的实用性和科学性;运用Topsis法对和平灌区进行节水农业综合效益评价,得到各年份的综合评分及其变化规律,从影响综合评分的主要因素出发分析了原因。结果表明,综合效益最高的是2016年,最低的是2012年。和平灌区节水农业综合评分随时间上升,并且逐渐趋于平稳。 相似文献
11.
Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration. 相似文献
12.
瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。 相似文献
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对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。 相似文献
14.
对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。 相似文献
15.
About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered. 相似文献
16.
在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。 相似文献
17.
Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications. 相似文献
18.
在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。 相似文献