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Woody plant diversity,structure and regeneration in the Ambo State Forest,South Gondar Zone,Northwest Ethiopia 被引量:2
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作者 Solomon Melaku Melese Belayneh Ayele 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期133-144,共12页
For this study in the Ambo State Forest on woody plant diversity, structure and regeneration, 70 quadrats, each 25 m by 25 m, were selected using a systematic random sampling technique and intervals of 100 m along a t... For this study in the Ambo State Forest on woody plant diversity, structure and regeneration, 70 quadrats, each 25 m by 25 m, were selected using a systematic random sampling technique and intervals of 100 m along a transect line. For assessing seedlings and saplings, two 2 × 10 m sub quadrats were set upon opposite sides of each main quadrat. Data on species diversity, abundance, structure, basal area, density, frequency and regeneration status were collected and analyzed using standard procedures and programs. Of 58 woody plant species identified, 69 % were trees, 16 % were shrubs, 12 % were tree/shrubs and 4 % were climbers. Fabaceae was the most speciesrich family comprising 17 species. The Shannon-Weiner diversity index was 2.73, and evenness was 0.67. The population structure in the cumulative diameter class frequency distribution revealed an interrupted and inverted J-shape with a very high decrease in higher diameter class. Acacia lahai (49 %) was the most important woody species with the highest importance value index. To maintain balanced structure, enhanced regeneration and protecting the forest from selective cutting are recommended. 展开更多
关键词 ambo Forest DIVERSITY Structure -Importance value index Regeneration status
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复凝聚法制备吲哚美辛缓释微囊的研究 被引量:8
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作者 宋明侠 相晓东 《天津药学》 2007年第5期29-31,共3页
目的:通过吲哚美辛微囊的制备研究,为吲哚美辛的缓释制剂提供科学依据。方法:以微囊的药物包封率为制备工艺优化指标,利用复凝聚法,通过正交实验得出微囊的最佳制备工艺条件。结果:该法所制备微囊的粒度分布在2.2~32.3μm之间... 目的:通过吲哚美辛微囊的制备研究,为吲哚美辛的缓释制剂提供科学依据。方法:以微囊的药物包封率为制备工艺优化指标,利用复凝聚法,通过正交实验得出微囊的最佳制备工艺条件。结果:该法所制备微囊的粒度分布在2.2~32.3μm之间,收率可达80%以上。结论:实验证明,吲哚美辛微囊比吲哚美辛片剂具有明显的缓释作用。 展开更多
关键词 复凝聚 吲哚美辛 缓释微囊
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基于改进候鸟迁徙优化的多目标批量流混合流水车间调度 被引量:7
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作者 汤洪涛 王丹南 +3 位作者 邵益平 赵文彬 江伟光 陈青丰 《上海交通大学学报》 EI CAS CSCD 北大核心 2022年第2期201-213,共13页
针对2+1+1型混合流水车间,研究了多目标不相等批量流混合流水车间调度问题,提出一种基于变邻域搜索的自适应候鸟迁徙优化(AMBO)算法,实现了最小化完工时间与最小平均在制品数量的多目标优化.相比原始候鸟迁徙算法,AMBO算法引入变邻域搜... 针对2+1+1型混合流水车间,研究了多目标不相等批量流混合流水车间调度问题,提出一种基于变邻域搜索的自适应候鸟迁徙优化(AMBO)算法,实现了最小化完工时间与最小平均在制品数量的多目标优化.相比原始候鸟迁徙算法,AMBO算法引入变邻域搜索策略,实现每个算子的权重随迭代次数自适应调整,并提出了时间窗算子,以提升交换算子搜索性能和收敛速度.对随机生成不同规模的订单进行算例研究,结果表明AMBO算法比候鸟迁徙优化算法、遗传算法具有更高的求解质量和收敛性能,从而验证了AMBO算法的有效性. 展开更多
关键词 批量流问题 混合流水车间调度问题 变邻域搜索 自适应候鸟迁徙优化 时间窗算子
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