共查询到20条相似文献，搜索用时 306 毫秒
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论述了休闲农业的概念和功能,介绍了北京、上海和成都等地发展休闲农业所取得的成绩;分析了淮安市休闲农业资源特点及开发利用中存在的主要问题;就淮安市休闲农业的发展提出有针对性、可操作性的建议。 相似文献
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发展休闲农业是乡村振兴战略实施的对策之一。与旺季相比，北方淡季休闲农业的需求明显较低，但是供给更低，因而形成北方淡季休闲农业均衡价格偏高而均衡数量偏低的现象。这种现象的根本解决方法是改善与休闲农业互相影响、互相促进的经济结构。一个国家或地区的经济结构由若干子系统组成，包括产业结构、地区结构、供求结构、生产中的要素结构、消费结构等。因此休闲农业的发展是一个系统工程。要完善这个系统工程，必须更有效地发展旺季休闲农业，做好优化经济结构的系统性工作，利用现代信息系统发展和完善休闲农业，改进相关技术以及改善休闲农业发展模式。 相似文献
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休闲农业是利用农业自然景观、农业生产条件、农业经营活动、农村人文资源,发展休闲、旅游的一种新型农业生产形态.宁夏休闲农业在近年来得到迅速发展,虽然在生态、技术、产业各方面都形成了一定优势,但也不可避免地存在一些问题,包括重视不够、宣传不足、缺乏规划、层次较低、规模偏小等,制约了宁夏休闲农业的整体发展和提升.该研究通过宁夏休闲农业SWOT分析,将与研究对象密切相关的优势、劣势、机遇和威胁等因素进行深入的比较分析和客观的识别评价,提出符合宁夏休闲农业发展状况的对策. 相似文献
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Segregation of form, color, movement, and depth: anatomy, physiology, and perception 总被引：63，自引：0，他引：63
Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze different aspects of the same retinal image: cells in cortical visual areas 1 and 2 and higher visual areas are segregated into three interdigitating subdivisions that differ in their selectivity for color, stereopsis, movement, and orientation. The pathways selective for form and color seem to be derived mainly from the parvocellular geniculate subdivisions, the depth- and movement-selective components from the magnocellular. At lower levels, in the retina and in the geniculate, cells in these two subdivisions differ in their color selectivity, contrast sensitivity, temporal properties, and spatial resolution. These major differences in the properties of cells at lower levels in each of the subdivisions led to the prediction that different visual functions, such as color, depth, movement, and form perception, should exhibit corresponding differences. Human perceptual experiments are remarkably consistent with these predictions. Moreover, perceptual experiments can be designed to ask which subdivisions of the system are responsible for particular visual abilities, such as figure/ground discrimination or perception of depth from perspective or relative movement--functions that might be difficult to deduce from single-cell response properties. 相似文献
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Mansfield E 《Science (New York, N.Y.)》1980,209(4461):1091-1093
R & D, through its effects on the rate of productivity increase, can significantly restrain the rate of inflation in the medium and long run. High rates of inflation damage the workings of the price system and impair the efficiency of practically all economic activities, including R & D. Findings suggest that the percentage increase between 1969 and 1979, in total real R & D expenditures, has been exaggerated due to the inadequacy of the gross national product deflator as applied to R & D. 相似文献
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The primary rocks are a sequence of titanium-rich basic volcanics, composed of clinopyroxene, plagioclase, and ilmenite with minor olivine, troilite, and native iron. The soil and microbreccias are respectively loose and compacted mixtures of fragments and aggregates of similar rocks, minerals, and glassy fragments and spheres. Impact events are reflected by the presence of shock metamorphosed rock fragments, breccias, and glasses and their resulting compaction to form complex breccias, glass-spattered surfaces, and numerous glass-lined craters. Chemistry of the glasses formed by the impact events is highly variable, and the high iron and nickel content of a few moundlike features suggests that at least some of the projectiles are iron and nickel-rich meteorites. 相似文献
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Maslansky R 《Science (New York, N.Y.)》2003,301(5639):1479-82; author reply 1479-82
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