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词关联规则层状稀疏主题编码模型 被引量:3
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作者 曹中华 夏家莉 +1 位作者 李光泉 张志斌 《小型微型计算机系统》 CSCD 北大核心 2019年第3期510-514,共5页
模型规则化可以通过给模型加入先验知识,而避免模型过拟合,并且能够使模型参数稀疏,选择出最有代表性的模型参数.具有稀疏性的主题特征能够更有效的表示文本语义信息,通过WordNet和Word2Vec可以得到相似词集,将相似词集的编码向量归属... 模型规则化可以通过给模型加入先验知识,而避免模型过拟合,并且能够使模型参数稀疏,选择出最有代表性的模型参数.具有稀疏性的主题特征能够更有效的表示文本语义信息,通过WordNet和Word2Vec可以得到相似词集,将相似词集的编码向量归属为相同组,构造相似词组语义约束,并将其表示为层状结构化先验信息,论文因此而实现了两种层状稀疏规则化方法,应用于主题编码模型.实验表明采用层状规则化的稀疏编码模型可以提高主题模型编码效果,学习到主题一致性、分类结果更好的文本主题信息. 展开更多
关键词 主题编码 层状规则 词分组 稀疏
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Structure characteristic and its evolution of Cu-W films prepared by dual-target magnetron sputtering deposition
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作者 周灵平 汪明朴 +3 位作者 彭坤 朱家俊 傅臻 李周 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2700-2706,共7页
Immiscible Cu-W alloy thin films were prepared using dual-target magnetron sputtering deposition process. The structure evolution of Cu-W thin films during preparation was investigated by X-ray diffraction, transmissi... Immiscible Cu-W alloy thin films were prepared using dual-target magnetron sputtering deposition process. The structure evolution of Cu-W thin films during preparation was investigated by X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy. In the initial stage of dual-target magnetron sputtering deposition process, an amorphous phase formed; then it crystallized and the analogy spinodal structure formed due to the bombardment of the sputtered particles during sputtering deposition process, the surface structure of the film without the bombardment of the sputtered particles was the amorphous one, the distribution of the crystalline and amorphous phase showed layer structure. The solid solubility with the analogy spinodal structure was calculated using the Vegard law. For Cu-13.7%W (mole fraction) film, its structure was composed of Cu-ll%W solution, Cu-37%W solution and pure Cu; for Cu 14.3%W film, it was composed of Cu-15%W solution, Cu-38%W solution, and pure Cu; for Cu-18.1%W film, it was composed of Cu-19%W solution, Cu-36% W solution and pure Cu. 展开更多
关键词 Cu-W thin film sputtering deposition amorphous phase layer structure solid solubiiity Vegard law
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四川省宁南县跑马铅锌矿成因浅析 被引量:8
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作者 贺光兴 孙启武 +1 位作者 夏传见 邓斌武 《地质找矿论丛》 CAS CSCD 2006年第B10期81-84,共4页
跑马铅锌矿为产于下寒武统麦地坪白云岩中的层控矿床,主要受层间破碎带控制,有两个含矿层,多呈层状产出。麦地坪段在沉积过程中铅、锌相对富集形成源层,经后期热液叠加改造富集成矿,为沉积改造型似层状(不规则状)铅锌矿床。
关键词 矿床成因 层控矿床 沉积改造型似层状(不规则状)铅锌矿床 跑马铅锌矿 四川省
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