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Establishing an eyeball-weight relationship for Litopenaeus vannamei using machine vision technology
This study aimed to establish a shrimp eyeball-weight relationship model for Litopenaeus vannamei using machine vision technology. A total of 295 shrimp were sampled from a recirculating aquaculture system (RAS). The long-axis length (d), body length (L), and body weight (W) of each individual was measured. The long axis length of the shrimp eyeball was identified and measured using machine vision technology. Continuous fitting and piecewise fitting models were used to construct the eyeball-weight relationship model for L. vannamei. The continuous fitting relationship model was described as: W = 38.865d2.7914, while the piecewise model was described as: d < 2 mm, W = 0.0326d3.7363, R² = 0.9288; 2 mm ≤ d < 3.9 mm, W = 0.0401d3.104, R² = 0.9629; 3.9 mm ≤ d < 5.8 mm, W = 0.0421d3.0311, R² = 0.9216; 5.8 mm < d, W = 0.103d2.6226, R² = 0.9457. The root mean square error (RMSE) of the piecewise fitting model (0.0244, 0.1575, 0.5034, 0.7072) was smaller than the continuous fitting model (0.8229). The correlation coefficient (R2) of the piecewise model (0.9288, 0.9629, 0.9216, and 0.9457) was similar to that of the continuous fitting model (R2 = 0.9621). The results indicated that the piecewise fitting model is suitable for calculating the biomass of L. vannamei in RAS and provides a novel way of estimating the biomass of L. vannamei cultured in RAS. The piecewise fitting model can also provide the foundation of evaluating the production of shrimp using underwater image recognition in intelligent aquaculture systems. 相似文献
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可持续发展类型与测度的理论探讨 总被引:2,自引:0,他引:2
可持续发展的类型划分与可持续发展的测度是可持续发展理论研究的重要内容。科学反应可持续发展的特征 ,有利于可持续发展类型划分 ,是可持续发展测度的依据和目标。本文运用人地关系协调分析法与经济分析法 ,特别是与替代弹性不变生产函数分析法 (C.E.S生产函数 )相结合 ,提出了可持续的人均国内生产总值 ,探讨了可持续发展中人文资本、自然资本相互协调、相互依存的关系特征 ,建立可持续发展测度的指标系统和可持续发展的类型体系 相似文献
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荔枝品种亲缘关系的AFLP分析 总被引:21,自引:4,他引:21
应用AFLP技术,对39个荔枝品种进行了遗传多样性分析及分类研究。筛选出适于荔枝AFLP分析的最佳引物组合3对,分别为EcoRI AAC+MseI CTG,EcoPd AGC+MseI CAT,EcoRI ACC+Msel CAT。在分子水平上,荔枝品种的遗传多样性并非形态学性状所体现的那样丰富。AFLP分析将39个荔枝品种分成了6组,与传统的以果皮龟裂片隆起类型为分类标准的分类没有一致性。初步建立起荔枝主要栽培品种的分子标记标准图谱。应用AFLP技术对来自两个不同地方的两个荔枝品种(桂味、妃子笑)进行了鉴别。 相似文献
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Effects of area and isolation of woodland patches on herbaceous plant species richness across Great Britain 总被引:5,自引:2,他引:5
Petit Sandrine Griffiths Leila Smart Simon S. Smith Geoff M. Stuart Rick C. Wright Simon M. 《Landscape Ecology》2004,19(5):463-471
Richness of Ancient Woodland Indicator plant species was analysed in 308 woodland patches that were surveyed during the Countryside Survey of Great Britain carried out in 1998. The Countryside Survey recorded vegetation plots and landscape structure in 569 stratified 1 km sample squares and developed a remotely-sensed land cover map of the UK. Using these datasets, we tested the hypothesis that Ancient Woodland Indicator species richness in woodland fragments was limited by patch area, shape and spatial isolation and that woodland patches located in the lowland region of Great Britain would respond differently than those in the upland region. The variation in Ancient Woodland Indicator species richness in the British lowlands (n = 218) was mainly explained by patch area and two measures of connectivity, the length of hedgerows and lines of trees in the 1 km square and the area of woodland within 500 m of the vegetation plot. By contrast, variation in Ancient Woodland Indicator species richness in the British uplands (n = 90) was related to Ellenberg scores of the vegetation communities sampled – a surrogate for habitat quality – and no significant effect of spatial structure was detected. It therefore appears that the degree of fragmentation of woodland in the British lowlands limits the distribution of Ancient Woodland Indicator species, while in the uplands, failed colonisation is a matter of habitat quality rather than a result of landscape structure.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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中国苜蓿育成品种遗传多样性及亲缘关系研究 总被引:1,自引:0,他引:1
以苜蓿的种子贮藏蛋白的多态性为研究指标,对中国14个审定登记的苜蓿育成品种的遗传多样性及亲缘关系进行了研究。研究结果表明:蛋白单体的分子量介于21.2~85.1kD之间,蛋白单体电泳图谱多态性品种间无显著的特异性;在参试的14个育成品种中,品种内基因多样性平均值(HS)为0.3136,总基因多样度(HT)为0.3741,基因分化系数(GST)为0.162;以λ=3.700为标准划分,14个育成品种划分为六个组群,各组群划分结果主要与参试品种的亲本来源有关,而与其种植地、育种地关系不大。 相似文献
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运筹学是关于做决定的科学,运筹学集数学和其他科学方法为一体,对现实问题进行模型化并提出解决方案,把它科学地应用到各企业管理中,可有效地帮助企业做出合理的决策. 相似文献