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91.
基于属性相似度的属性约简算法 总被引:11,自引:0,他引:11
为解决粗糙集属性约简算法存在的诸多问题,从属性相似度出发推导出属性相似度与粒度相似度的一致性,进而提出了一种基于属性相似度的属性约简算法,主要包括采用分明矩阵法求条件属性集的约简,核的求取,可省属性的相似度计算和最简约简的求出等步骤,仿真与对比分析表明其计算简便、效果显著。 相似文献
92.
Rats exposed to simultaneous compounds of 1 neutral flavor with dilute (2%) sucrose and a 2nd flavor with dilute (2%) maltodextrin subsequently consumed both flavors in preference to a 3rd flavor that was never paired with a palatable taste. Brief training exposure under ad lib food and water minimized the postingestive effects of nutrients, emphasizing the contribution of palatability to these preferences. Devaluation of sucrose or maltodextrin by pairing with illness (Experiment 1) or sensory-specific satiety (Experiment 2) selectively reduced the preference for the flavor previously paired with the devalued reinforcer. Such reinforcer-specific devaluation effects suggest that palatability-based learned flavor preferences are underpinned by a Pavlovian process whereby the cue flavor is associated with the taste of the concurrently consumed palatable reinforcer. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
分析了智能大厦系统规划方案的作用,提出采用模糊多属性群体决策法对系统规划方案进行评价,给出了模糊判断矩阵和隶属度的构造方法,详细介绍了模糊多属性群体决策法在智能大厦的系统规划方案决策中的计算步骤及方法。 相似文献
94.
介绍了房产地籍管理系统的开发。将房屋、空间几何信息、结构化属性信息、地籍信息和其他相关信息融为一体进行统一管理。用MFC和ObjectARX等技术建立了用户化绘制环境和地理几何实体特征的标识。用ODBC和数据库等技术实现空间数据和属性数据相互驱动查询,实现在网络环境下总部与下级部门和下级部门之间的数据交换。本系统已投入实际使用,效果很好;易于扩展,有较强的辅助分析和决策能力。 相似文献
95.
In the southeast in Norrköping, Sweden, is a small fjord-like bay called Slätbaken. The water quality in Slätbaken—with its narrow outlet to the Baltic Sea—depends highly on the water quality of the streams that flow in it. While point pollution sources can be identified easily in general, the non-point sources are harder to find. The most important sources for non-point pollution are agricultural areas, and the pollutants are mostly nutrients like phosphorus, which come from the fertilisation of the fields. One important catchment area for Slätbaken is the 57.7 km2 Gisselö river basin (part of the topographic map 8GNO), which contains large agricultural areas.The transport of water pollutants is based on the same hydrological processes as erosion and sediment transport. The implementation of such a model in a GIS allows the analysis of a large area with a high resolution. When choosing the model, special attention was paid to the possibility of using a verified model that is easy to implement in a commercial GIS without the need of too much expert knowledge. This may allow its widespread use in many administrative applications that need non-point source information. A feasibility test for an enhanced GIS USLE model was done in the Gisselö drainage basin before it was implemented for all river basins in the whole administrative area of Norrköpings kommun.It is possible to use the suggested simplified USLE model to estimate the load of both pollutants and sediments, and it is able to show the areas that are critical for the water quality at the outlet of the water basin. The model has been evaluated in three studies [Int. J. Geogr. Inf. Syst. 2 (4) (1988) 365; A GIS to target critical areas for non point source management, in: Proceedings of the International Non Point Source Management Symposium, Austin, TX, November 7, 1989; Vatten 48 (1992) 117]. Then, implemented in a very simple GIS that allowed only rough estimates of terrain models and distances, the model was able to estimate the total suspended solids (TSS) and total phosphorus (TP) loads in the Svartå river basin of 1539 km2 in the same region as Gisselö and the Bornsjö river basin outside Stockholm. Besides an estimated R2 of 0.91–0.98 (verified by a more than one year measurement from manual and automated sampling stations in the whole river basin), the benefit with the GIS implemented USLE was the possibility to identify the risk areas with high spatial accuracy. During the last decade, both available databases and software have changed the possibilities to identify areas at risk of nutrient leakage. Schein [GIS Methods for Monitoring Sustainable Development by Analysis of Land-use and Land Cover Changes in the Surroundings of Linköping (Sweden), Institut für Photogrammetrie und Fernerkundung, Technische Universität Dresden, Germany] and Schein and Sivertun [Method and models for sustainable development monitoring and analyses in GIS, in: Proceedings of the International Workshop on Geo-Spatial Knowledge Processing for Natural Resource Management, University of Insubria, Varese, Italy, June 28–29, 2001] show that the enhanced land use data available through the European Union agricultural support program can be used together with remote sensing data to fine tune the modified GIS USLE model. The problems with the new 50×50 m digital elevation data now available are also pointed out here. Obvious errors in the data and possibilities to enhance the model by introducing a better terrain model were two important suggestions in these works. In this article, two modifications to the original model are suggested. One is enhancement of the digital terrain model by using height curves from the digital 1:50 000 scale topographic map, and the other is a smooth distance function that better reflects the impact of nutrients on water bodies.Because of its easy implementation on standard low cost systems, the GIS USLE model is suitable for analysing huge areas for critical places. The results can lead to more detailed studies in the risk areas thus identified or to investigations on the effect of land use changes, or can be used simply for taking care in the use of fertilisers and other chemicals in the critical agricultural areas. 相似文献
96.
AutoCAD应用文档的开发 总被引:1,自引:0,他引:1
以一个应用实例介绍了 Auto CAD的属性功能、定义、编辑以及属性块与 DCL、Auto L ISP相结合生成整部件明细栏的方法 ,并简要介绍了属性提取及其与数据库接口的方法 ,以便将 Auto CAD产品的设计信息与PDM相结合以生成各种文档。 相似文献
97.
连续属性信息系统的规则约简根本问题是属性在连续范围取任何实值,使得应用与离散属性的规则约简方法难于使用。因此解决连续属性信息系统的规则约简问题为当前研究领域所关注。该文结合粗集与模糊集理论与方法提出了一种新的数据处理与规则约简方法,并给出了该方法的实验结果。 相似文献
98.
张家明 《计算机研究与发展》1998,35(4):296-300
文中通过对关系模式中的属性进行适当的分类,讨论了一个属性成为主属性应该满足的条件,并在文献「4」、「5」「6」的基础上,采用闭包,实现了利用Armstrong公理进行函数信赖推导的过程,从而给出了一个简便的求解关系模式全部主属性的多项式时间算法。 相似文献
99.
随着ISO10646的出台,庞大的汉字词集的属性分析是一个迫切需要解决的难题,本文主要阐述了采用C/S模式的汉字词属性分析和重组系统的数据模型,并简单介绍了系统的设计要点。 相似文献
100.
服装消费行为与个人基本属性的关系 总被引:8,自引:0,他引:8
从理论上提出了服装消费者行为的分析模式,并以女性为对象对服装消费行为与个人基本属性的关系进行了研究。研究结果表明:消费者购买服装时所重视铁仍然是服装内在的各种属性-颜色、做工和款式等,而对品牌和产地等外在属性的重视程度较低;消费者的购买与穿着行为及其着装意识、理智、慎重、并带有较强的求新、求美倾向;消费者的具人基本属性对其服装购买与穿着行为,着装意识等有明显影响,其中年龄、职业和经济收入对服装属性 相似文献