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961.
Using semidifferentiable concept for set-valued mapping and defining strong semiconpact for set-valued mapping. The article studies the existence of positive fixed point for semidifferentiable and Upper semicontinuous set-valued 1-set-contractive mapping. 相似文献
962.
Architecture of Logistics system is the interior operation environment and business platform for Logistics companies, which is to steer to build special logistics system and tactics frame-saw to realize the company's objectives. Further more, characteristic and design principle of architecture are mentioned. There are 4 levels in this article to discuss the architecture of TPL system. Six elements contained in the architecture are mentioned: information platform, tech-equipment platform, knowledge platform, organization platform, business platform and functional platform, Furthermore, the mutual connection among which is analyzed as a whole. In conclusion, measure of the transfer from traditional storage and transportation to modern logistics is discussed. 相似文献
963.
In this paper, the factors influencing the foundation scheme of high-rise buildings are analyzed. In accordance with the complex hierarchical structure and the uncertainty of foundation scheme, a knowledge base of hierarchical structure is set up and an inexact reasoning is realized. Then, the expert system for high-rise buildings foundation scheme (TBFES) is built on the knowledge base with the expert system tool CLIPS. 相似文献
964.
A customer segmentation method based on dynamic SOM and RFM indicators is presented. Firstly, customer clusters is generated by DSOM clustering analysis. Secondly, customer loyalty, customer scale and customer credit are simulated by RFM behaviors of customer, and then customer clusters are identified. Finally, the value of customers can be decided according to the customer segmentation results, and enterprises are able to provide better different service levels to different customers. It provides customer strategies of enterprises with an effective support and decision-making. 相似文献
965.
Zhu Jisheng 《保鲜与加工》1988,(1)
In this paper, we obtained one implicit function theorm,which, in the inverse function cases, becomes to the necessary and sufficient condition for the mapping is a homeomorphism. 相似文献
966.
967.
Data-mining is a composite and multi - disciplinary technology newly developed. This paper will start by describing the fundamentals and basic methods of the technology followed by an overview of the latest development of its applications, problems and hurdles currently facing and the way forward and future work. 相似文献
968.
From the topological angle and byintroducing the definitions of continuous mapping, open mapping, closed mapping,homeomorphic mapping, submatroid and quotient matroids, under which the qualities of matroids are studied, and some equivalent condictions are obtained. Inadditional, whether the independent set,dependent set and circuit of matroids are held under these mappings is discussed. 相似文献
969.
Mila M. Ramos Luz Marina Alvare Peter Shelton Hugo Besemer 《Journal Of Agricultural & Food Information》2013,14(1):27-36
Literature searching instruments are available via the Internet, but one has to conduct several individual searches to retrieve relevant scholarly materials for research. This scenario led information experts from the Consultative Group on International Agricultural Research (CGIAR) to find ways to make life easier for scientists. The collaboration among Information and IT managers resulted in the launch of the CGIAR Virtual Library (CGVLibrary) in 2006. CGIAR supports 15 diverse international centers, located worldwide, which generate scholarly research results that are considered as public goods and must be shared freely with the international community. The CGVLibrary enables federated searching of catalogs and databases and carries hyperlinks to full-text CGIAR documents. This article provides an analysis of the content of the CGVLibrary, of the various information avenues it opens for improving access to agricultural research, and of how the tool is being improved and marketed to promote awareness and worldwide use. 相似文献
970.
Jens Gebauer Eike Luedeling Karl Hammer Maher Nagieb Andreas Buerkert 《Genetic Resources and Crop Evolution》2007,54(3):465-481
Several botanical studies have been conducted in different parts of Oman, but knowledge about agro-biodiversity in the rapidly decaying ancient mountain oases of this country remains scarce. To fill this gap we assessed the genetic resources of three mountain oases in the al-Hajar range using a GIS-based field survey and farmer interviews. While arid conditions prevail throughout the mountain range, the different elevations of Balad Seet (950–1020 m a.s.l.), Maqta (930–1180 m a.s.l.) and Al Jabal al Akhdar (1750–1930 m a.s.l.) provide markedly differing agro-climatic conditions. Overall, 107 different crop species were identified belonging to 39 families. Species number was highest among fruits (33 spp.), followed by vegetables (24 spp.). Intensive irrigation allows cultivation of a broad range of species at all oases. However, the number of species varied significantly between sites. Fruit species diversity and homogeneity of distribution of individual fruit species was highest at Balad Seet and lowest at Maqta as indicated by respective Shannon indices of 1.00 and 0.39 and evenness values of 32% and 16%. Century plant (Agave americana L.), faba bean (Vicia faba L. var. minor Peterm. em. Harz) and lentil (Lens culinaris Medik.) were identified as relict crops, supporting oral reports of past cultivation and providing evidence of genetic erosion. Some species, such as the temperate fruits of Al Jabal al Akhdar, were exclusively found at the coolest site, while others only occurred at the hotter locations. Overall greatest species similarity was found between Balad Seet and Al Jabal al Akhdar as indicated by a Sørensen coefficient of similarity of 67%. At all oases a multilayered vegetation structure dominated with a canopy, an understory and a ground layer. Greatest species richness was recorded in the lowest stratum. Overall the study shows a location-specific but surprisingly diverse mosaic of crops in Omani mountain oases which merits further studies and conservation efforts. 相似文献