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辽宁鸭绿沙塘鳢年龄与生长的研究
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作者 段友健 骆小年 +2 位作者 韩牧轩 李文康 林少卿 《水产科学》 北大核心 2025年第3期484-489,共6页
为了稳健地描述和推断鱼类的生长特点,有效降低模型的选择误差,于2018年8月至2019年1月用地笼(网目1.5 cm)和电鱼机在鸭绿江支流(大洋河、瑷河、蒲石河)、太子河上游和碧流河上游采集鸭绿沙塘鳢204尾,利用耳石鉴定年龄,研究了其生长特... 为了稳健地描述和推断鱼类的生长特点,有效降低模型的选择误差,于2018年8月至2019年1月用地笼(网目1.5 cm)和电鱼机在鸭绿江支流(大洋河、瑷河、蒲石河)、太子河上游和碧流河上游采集鸭绿沙塘鳢204尾,利用耳石鉴定年龄,研究了其生长特性。试验结果显示:鸭绿沙塘鳢年龄结构简单,仅由3个龄组构成,其中,雌性有2个龄组组成,雄性包含所有3个龄组;通过生长方程构建,估算的渐进式方程、直线方程和乘幂函数3种备选生长模型的赤池信息权重系数分别为0.019、0.086和0.895;由于Power生长模型所对应的权重系数远高于其他两个备选模型的估算值,不需要计算平均生长模型,Power生长模型为描述鸭绿沙塘鳢生长特性的最优模型,生长方程为L_(t)=69.7+1.439 t^(3.688)。试验结果可为鸭绿沙塘鳢种群动态研究和渔业管理政策提供基础数据,建议降低捕捞强度,并开展鸭绿沙塘鳢等土著鱼类的资源养护。 展开更多
关键词 鸭绿沙塘鳢 信息理论方法 生长模型
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Optimization model of unascertained measurement for underground mining method selection and its application 被引量:6
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作者 刘爱华 董蕾 董陇军 《Journal of Central South University》 SCIE EI CAS 2010年第4期744-749,共6页
An optimization model of underground mining method selection was established on the basis of the unascertained measurement theory.Considering the geologic conditions,technology,economy and safety production,ten main f... An optimization model of underground mining method selection was established on the basis of the unascertained measurement theory.Considering the geologic conditions,technology,economy and safety production,ten main factors influencing the selection of mining method were taken into account,and the comprehensive evaluation index system of mining method selection was constructed.The unascertained evaluation indices corresponding to the selected factors for the actual situation were solved both qualitatively and quantitatively.New measurement standards were constructed.Then,the unascertained measurement function of each evaluation index was established.The index weights of the factors were calculated by entropy theory,and credible degree recognition criteria were established according to the unascertained measurement theory.The results of mining method evaluation were obtained using the credible degree criteria,thus the best underground mining method was determined.Furthermore,this model was employed for the comprehensive evaluation and selection of the chosen standard mining methods in Xinli Gold Mine in Sanshandao of China.The results show that the relative superiority degrees of mining methods can be calculated using the unascertained measurement optimization model,so the optimal method can be easily determined.Meanwhile,the proposed method can take into account large amount of uncertain information in mining method selection,which can provide an effective way for selecting the optimal underground mining method. 展开更多
关键词 mining engineering underground mining method optimization model unascertained measurement theory information entropy
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