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1.
借助改进熵权法对评价指标进行赋权,结合灰关联分析和模糊物元分析理论,建立了改进熵和灰关联分析的模糊物元分析模型,通过案例分析表明了该模型是有效的。对传统熵权法进行改进,使得熵权法的应用范围更广泛、更实用,并应用到评价指标的赋权中。将灰关联分析理论和模糊物元分析理论相结合,建立了改进熵和灰关联分析的模糊物元分析模型,并应用到节水灌溉项目投资决策中,能够为节水灌溉项目投资决策提供理论依据。  相似文献   

2.
为解决水质评价中评价指标众多,存在复杂性、模糊性和不确定性等问题,采用基于指标变换值的模糊物元模型对克孜河河流2012年的水质进行评价,并与传统的单因子评价法和灰色关联分析法评价结果进行对比.结果表明:模糊物元评价得出不同时期河流水质级别均为Ⅰ级;基于指标变换值的模糊物元得出的评价结果与灰色关联分析法是一致的,与单因子评价法的评价结果在5月8日的取样值略有不同;基于指标变换值的模糊物元模型应用在该河流水质评价中是合理可行的,且计算简便实用.  相似文献   

3.
该文探讨了灌区评估指标体系的建立方法,对评估指标的选取与预处理进行了系统分析,并尝试应用灰色系统理论中的灰关联度分析法,对灌区评估指标进行关联分析,从而很方便地进行灌区之间的评估、排队及比较,与传统的强制打分法相比,此法简便易行,无需预先建立评判标准,因此是一种新的评估分析法。  相似文献   

4.
丁丽宏 《节水灌溉》2012,(10):56-58,62
考虑到影响引水方案的因素众多,且存在一定的层次,建立了多层次引水方案的灰色关联综合评价方法。由于各评价指标的权重具有不确定性和主观性,结合各指标所提供的信息量,将信息熵理论引入指标权重的确定中。首先运用熵权法理论确定指标权重,然后由灰关联分析法,对低层次子集进行关联度分析,进而对各子集的关联度进行高层次综合,综合排序结果,按隶属度最大原则,确定方案的优劣。实例分析表明,该方法是合理有效的,且可以用于其他工程方案的优选。  相似文献   

5.
提出节水型社会内涵与评价指标体系设计原则,建立了包括定量和定性两大类指标的评价指标体系,并利用灰关联分析法和模糊综合评价法建立节水型社会评价模型。实证部分对张掖市2005年节水型社会建设水平进行了分析评价。结果表明,2005年张掖市节水型社会建设处在起步阶段,节水型社会建设需要进一步发展。  相似文献   

6.
克服传统的TOPSIS法在确定指标权重以及贫信息决策等方面的不足,利用基于灰关联分析的加权TOPSIS法,建立评价模型,以水稻理论产量、产量构成要素指标、雨水总利用率、作物需水量、水分生产率、总磷释放量和氨氮释放量共10项指标为评价指标,对8个水稻控制灌排方案进行综合评价,结果客观可靠,为水稻灌排方案的优选提供了科学途径。  相似文献   

7.
结合灰色系统白化权函数构建了电网企业电能计量消隐改造工程项目技术经济综合评价模型,根据不同技术经济评价指标划分不同的评价灰类,利用层次分析法计算各评价指标的权重,得出该电网企业电能计量消隐改造工程项目技术经济效果结论。  相似文献   

8.
借助改进熵权法对评价指标进行赋权,在灰关联分析和模糊物元分析理论的基础上,建立了改进熵和灰关联分析的模糊物元分析模型。根据灰色关联度的大小对评价对象进行排序,并将其应用到农业节水灌溉项目的优选中,说明此模型的合理性。  相似文献   

9.
基于主成分分析的电子信息企业财务评价   总被引:2,自引:0,他引:2  
传统财务分析法的指标之间都是相互关联的,往往导致重复评价或者主观赋权。而主成分分析法是一种多指标决策的统计方法,能有效弥补传统分析方法的弊端。本文采取电子信息类企业的财务数据,构建一个主成分分析模型,利用统计软件SPSS计算,得到电子信息类企业的财务评估得分,进而做出综合性评价。  相似文献   

10.
王平山 《农机化研究》2012,34(5):196-199
将灰色系统理论中的灰关联分析法与可靠性理论中的故障树分析法结合,并引入到剪草机内燃机无法启动的故障分析中,通过故障树底事件结构中的重要度的计算以及灰关联度的计算和排序,对内燃机无法启动故障树分析中故障发生可能性的大小进行分析判断,从而为预防故障的发生提供理论依据。实践表明,该方法行之有效,分析结果可靠。  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  
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   

13.
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  
《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.
赵异 《湖南农机》2007,(3):31-32
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.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
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   

19.
农村信息化服务的现状及建设措施   总被引:2,自引:0,他引:2  
分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。  相似文献   

20.
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   

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