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Based on published reports and direct observation, the common resources of landscape plant species in the Shanghai area were
identified and studied in terms of the landscape characteristics of timing sequence changes over a one year time period. The
results showed that there were 199 common landscape plant species in Shanghai, distributed in 67 families and 129 genera.
These plants were categorized by three ornamental characteristics: flowers, foliage and fruits. The species were thus further
analyzed according to the time periods which these characteristics were present. The results showed that flower ornamental
distributed throughout the year, particularly from April to June, and plant species with colorful foliage could be seen every
month, and particularly in November and December. On the other hand, few plant species with fruit ornamentals were observed
in Shanghai area. The diversity of landscape timing sequence changes of the 199 plant species under examination was then analyzed
by using the Shannon-Weiner and Simpson index formulas. The results showed that the higher diversity was observed in January,
February and from August to October, while the lowest diversity was recorded from March to July and during November and December.
The diversity of landscape characteristics of these plants was ranked according to foliage, flowers and fruit. Using this
method, one park and one plant community were selected to evaluate the advantages and disadvantages of their time-changing
plant landscape, with the goal of assessing the validity of the chosen ranking method. These results in the present study
would be helpful to evaluate the plant landscape in a specified space and further enrich the diversity of plant and landscape
by a target-oriented way. 相似文献
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协同制造是一种能够实现快速响应市场的生产模式,该生产模式已经成为21世纪制造业发展的必然趋势.为了实现当前制造环境下制造资源共享与优化配置,描述了企业间协同制造的基本概念,提出了协同制造任务的分配和资源发现,分析了协同制造的策略与运行模式及战略伙伴的选择,比较了几种算法的优缺点,给出了应用实例,用遗传算法对事例进行了论证并对事例进行了优化,得出了可行性的结论. 相似文献