排序方式： 共有35条查询结果，搜索用时 421 毫秒
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抗生素对中嘉8号杨叶片愈伤组织诱导和不定芽形成影响 总被引：1，自引：0，他引：1
探讨了4种抗生素对中嘉8号杨叶片愈伤组织的诱导及不定芽形成的影响。结果表明:噻孢霉素、羧苄青霉素和链霉素的浓度均为200 mgL-1时,不定芽分化率分别为73.3%、15.6%和6.7%,卡那霉素抑制愈伤组织和不定芽的发生,对芽的生长也有抑制作用。所以噻孢霉素可作为首选抑菌剂。随着卡那霉素浓度的提高,不定芽的存活率逐渐降低。当卡那霉素浓度≥60mg/L时,芽存活率为0。在筛选转化体时,卡那霉素对芽苗使用浓度以40-50 mg L-1为宜。 相似文献
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李晓虹 《武汉工程职业技术学院学报》2009,21(2):32-34
工业对讲设备主要用于各厂矿内部的生产指挥和调度联络,是现代化大型企业内部必不可少的通讯设备之一。介绍了一套负载20个扬声器的基于GY2×275W扩音机的工业对讲系统的组成、设计及其音频信号的传输流程。 相似文献
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Mahmoud Rokaya Elsayed Atlam Masao FuketaAuthor VitaeTshering C. DorjiAuthor Vitae Jun-ichi AoeAuthor Vitae 《Information processing & management》2008
Information retrieval involves finding some desired information in a store of information or a database. In this paper, Co-word analysis will be used to achieve a ranking of a selected sample of FA terms. Based on this ranking a better arranging of search results can be achieved. Experimental results achieved using 41 MB of data (7660 documents) in the field of sports. The corpus was collected from CNN newspaper, sports field. This corpus was chosen to be distributed over 11 sub-fields of the field sports from the experimental results, the average precision increased by 18.3% after applying the proposed arranging scheme depending on the absolute frequency to count the terms weights, and the average precision increased by 17.2% after applying the proposed arranging scheme depending on a formula based on “TF∗IDF” to count the terms weights. 相似文献
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《Information processing & management》2023,60(1):103168
Detection at an early stage is vital for the diagnosis of the majority of critical illnesses and is the same for identifying people suffering from depression. Nowadays, a number of researches have been done successfully to identify depressed persons based on their social media postings. However, an unexpected bias has been observed in these studies, which can be due to various factors like unequal data distribution. In this paper, the imbalance found in terms of participation in the various age groups and demographics is normalized using the one-shot decision approach. Further, we present an ensemble model combining SVM and KNN with the intrinsic explainability in conjunction with noisy label correction approaches, offering an innovative solution to the problem of distinguishing between depression symptoms and suicidal ideas. We achieved a final classification accuracy of 98.05%, with the proposed ensemble model ensuring that the data classification is not biased in any manner. 相似文献