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活性知识组件(LKC)的概念、原型及实现 被引量:5
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作者 张晓阳 霍达 杨俊学 《计算机工程与应用》 CSCD 北大核心 2003年第16期32-35,共4页
知识共享和再利用是目前知识工程研究和应用中的一个重点。与现有的Ontologies和Problem-solvingmethods(PSMs)技术相对应,文章提出了活性知识组件LKC(Liveknowledgecomponent)的概念、原型及实现LKC要解决的主要问题。LKC知识组件化技... 知识共享和再利用是目前知识工程研究和应用中的一个重点。与现有的Ontologies和Problem-solvingmethods(PSMs)技术相对应,文章提出了活性知识组件LKC(Liveknowledgecomponent)的概念、原型及实现LKC要解决的主要问题。LKC知识组件化技术可与Ontologies技术及PSMs技术相互补充,用于构建高效的知识和应用系统。 展开更多
关键词 活性知识组件 lkc Ontologies Problem-solving METHODS
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Estimation model of potassium content in cotton leaves based on hyperspectral information of multi-leaf position
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作者 Qiushuang Yao Huihan Wang +6 位作者 Ze Zhang Shizhe Qin Lulu Ma Xiangyu Chen Hongyu Wang Lu Wang Xin Lü 《Journal of Integrative Agriculture》 2025年第11期4225-4241,共17页
Potassium(K)is a highly mobile nutrient element that continuously adjusts its demand strategy among and within cotton leaves through redistribution,indirectly leading to variations in the leaf potassium content(LKC,%)... Potassium(K)is a highly mobile nutrient element that continuously adjusts its demand strategy among and within cotton leaves through redistribution,indirectly leading to variations in the leaf potassium content(LKC,%)at different leaf positions.However,due to the interaction between light and leaf age,leaf sensitivity to this change varies at different positions,including the reflection and absorption of the spectrum.Selecting the optimal leaf position for monitoring is a crucial factor in the rapid and accurate evaluation of cotton LKC using spectral remote sensing technology.Therefore,this study proposes a comprehensive multi-leaf position estimation model based on the vertical distribution characteristics of LKC from top to bottom,aiming to achieve an accurate estimation of cotton LKC and optimize the strategy for selecting the monitored leaf position.Between 2020 and 2021,we collected hyperspectral imaging data of the main stem leaves at different positions from top to bottom(Li,i=1,2,3,...,n)during the cotton budding,flowering,and boll-setting stages.Vertical distribution characteristics,sensitivity differences,and spectral correlations of LKC at different leaf positions were investigated.Additionally,the optimal range of the dominant leaf position for monitoring was determined.Partial least squares regression(PLSR),random forest regression(RFR),support vector machine regression(SVR),and the entropy weight method(EWM)were employed to develop LKC estimation models for single-and multi-leaf positions.The results showed a vertical heterogeneous distribution of cotton LKC,with LKC initially increasing and then gradually decreasing from top to bottom;the average LKC of cotton reached its maximum value at the flowering stage.The upper leaf position demonstrated greater sensitivity to K and exhibited a stronger correlation with the spectrum.The selected dominant leaf positions for the three growth stages were L1-L5,L1-L4,and L1-L2,respectively.Based on the dominant leaf position monitoring range,the optimal single leaf position models for estimating LKC during the three growth stages were PLSR-L4,PLSR-L1,and SVR-L2,with the coefficient of determination of the validation set(R2val)being 0.786,0.580,and 0.768,and the root-mean-square error of the validation set(RMSEval)being 0.168,0.197,and 0.191,respectively.The multi-leaf position LKC estimation model was constructed by EWM with R2val being 0.887,0.728,and 0.703,and RMSEval being 0.134,0.172,and 0.209,respectively.In contrast,the newly developed multi-leaf position comprehensive estimation model yielded superior results,improving the model’s stability based on high accuracy,especially during the budding and flowering stages.These findings hold significant importance for investigating cotton LKC spectral models and selecting suitable leaf positions for field monitoring. 展开更多
关键词 HYPERSPECTRAL vertical heterogeneity leaf position COTTON leaf potassium content(lkc)
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离子交换树脂提取硫酸粘菌素的性能对比研究 被引量:1
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作者 何淑旺 李树英 +2 位作者 刘长涛 蔡琨 段洪东 《潍坊学院学报》 2016年第2期20-23,65,共5页
本文研究了LKC150弱酸阳离子树脂提取硫酸粘菌素的各项性能指标,并利用动态饱和吸附试验对LKC150和FPC3500两种树脂进行了对比,以吸附量、解析率、解析液质量为评价指标,考察了两种树脂静态吸附解析、动态吸附解析性能。结果表明:在硫... 本文研究了LKC150弱酸阳离子树脂提取硫酸粘菌素的各项性能指标,并利用动态饱和吸附试验对LKC150和FPC3500两种树脂进行了对比,以吸附量、解析率、解析液质量为评价指标,考察了两种树脂静态吸附解析、动态吸附解析性能。结果表明:在硫酸粘菌素提取方面,LKC150吸附解析速率优于FPC3500,筛选出了最佳树脂,实现了树脂国产化,降低了生产成本。 展开更多
关键词 硫酸粘菌素 lkc150 提取 吸附率 解析率
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Congenital Cervico-Mandibular Cystic Lymphangioma in Pediatric Surgical Setting in Guinea
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作者 Thierno Saïdou Barry Mohamed Lamine Sadou Sacko +8 位作者 Balla Keita Aissatou Bailo Balde Mamadou Alpha Diallo Moussa Conde Ibrahima Kalil Dioubate Mory Sangare Salamata Sall Mariama Dalanda Diallo Daniel Agbo-Panzo 《Open Journal of Pediatrics》 2024年第1期164-173,共10页
Introduction: Cystic lymphangiomas are rare benign malformative tumors of the lymphatic system of obscure etiopathogenesis. The cervico-facial location remains the most common (75%). Although benign, these tumors rema... Introduction: Cystic lymphangiomas are rare benign malformative tumors of the lymphatic system of obscure etiopathogenesis. The cervico-facial location remains the most common (75%). Although benign, these tumors remain potentially fatal, due to possible compression of the upper aero-digestive tract. The aim of this work is to study the epidemiological, diagnostic and therapeutic characteristics of cervico-mandibular congenital cystic lymphangiomas in the pediatric surgery department of the Donka National Hospital (HND) Conakry. Patients and methods: This is a retrospective and descriptive study of 13 files lasting 7 years from January 2015 to December 31, 2021. The files of children whose age is less than or equal to 15 years operated on cervical tumor with histological evidence of cystic lymphangioma were retained. The data were analyzed using SPSS statistical software 21 and anonymously. Results: The incidence of this study was 1.86 cases per year and a sex ratio of 0.62 in favor of girls. The average age was 8 months 19 days. In the antecedents, we only find poorly monitored pregnancies. The average size of the tumors was 11.85 cm. Cervical ultrasound and standard x-ray of the cervical mass were the only examinations performed. Total surgical excision of the cervical tumor was performed in all patients. The mass was polycystic on exploration. The histological examination of the surgical specimens was in favor of a cystic lymphangioma. The surgical consequences were simple in 11 patients (84.62%) and complicated by parietal suppuration in 2 cases (15.38%). There were no cases of recurrence after one year of follow-up. Conclusion: Cervico-mandibular cystic lymphangiomas are the most frequent locations of congenital lymphangiomas in children. Their severity is linked to the risk of compression of the aero-digestive tracts. Their diagnosis must be confirmed by the histology of the surgical specimen. Despite the therapeutic arsenal, excision of the cystic mass remains the only effective alternative in our socio-economic conditions to avoid recurrences and loss of follow-up of patients. 展开更多
关键词 Congenital Cystic Lymphangioma (lkc) CHILD Pediatric Surgery Guinea
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