情报学术语承载了情报学科基础知识与核心概念。从概念维度梳理与分析情报学术语对推动学科发展、助力下游知识挖掘任务具有重要意义。面对数量快速增长的科技文献,自动术语抽取替代了人工筛选,但现有方法严重依赖大规模标注数据集,难...情报学术语承载了情报学科基础知识与核心概念。从概念维度梳理与分析情报学术语对推动学科发展、助力下游知识挖掘任务具有重要意义。面对数量快速增长的科技文献,自动术语抽取替代了人工筛选,但现有方法严重依赖大规模标注数据集,难以迁移至低资源场景。本文设计了一种生成式情报学术语抽取方法(generative term extraction for information science,GTX-IS),将传统基于序列标注的抽取式任务转化为序列到序列的生成式任务。结合小样本学习策略与有监督微调,提升面向特定任务的文本生成能力,能够在低资源有标签数据集场景下较为精准地抽取情报学术语。对于抽取结果,本文进一步开展了情报学领域术语发现及多维知识挖掘。综合运用全文科学计量与信息计量方法,从术语自身、术语间关联、时间信息等维度,对术语的出现频次、生命周期、共现信息等进行统计分析与知识挖掘。采用社会网络分析方法,结合时间维度特征,从术语角度出发,完善期刊的动态简介,探究情报学研究热点、演变历程和未来发展趋势。本文方法在术语抽取实验中的表现超越了全部13种主流生成式和抽取式模型,展现出较强的小样本学习能力,为领域信息抽取提供了新的思路。展开更多
为合理调节或优化传统钢板剪力墙(steel plate shear wall,SPSW)的抗震性能,本文提出了一种新型的带圆形压痕的钢板剪力墙结构(steel plate shear wall with circle dents,SPSW-CD)。基于有限元方法系统研究了压痕孔径、压痕孔距、压痕...为合理调节或优化传统钢板剪力墙(steel plate shear wall,SPSW)的抗震性能,本文提出了一种新型的带圆形压痕的钢板剪力墙结构(steel plate shear wall with circle dents,SPSW-CD)。基于有限元方法系统研究了压痕孔径、压痕孔距、压痕深度、钢板厚度和钢材强度等参数对SPSW-CD抗侧性能的影响,提出了四边连接SPSW-CD抗侧刚度及水平承载力的简化计算公式。分析结果表明随着压痕孔径增加,SPSW-CD的初始抗侧刚度及水平承载力均呈降低趋势;压痕孔距及钢板厚度越大,SPSW-CD抗侧性能越优。随着钢材强度增加,SPSW-CD水平承载力呈明显的增大趋势,但对其抗侧刚度影响不明显。压痕深度对SPSW-CD抗侧性能的影响可忽略。SPSW-CD抗侧刚度及水平承载力计算公式计算误差均小于10%,研究成果可用于此类结构的工程设计。展开更多
三角引用是一种融合直接引用关系、耦合关系和共被引关系的特殊引用结构,具有较高的研究价值与拓展意义。为了解同一篇文章在三角引用中不同位置的表现,提出正向三角引用、双向三角引用和逆向三角引用。以Web of Science核心合集数据库...三角引用是一种融合直接引用关系、耦合关系和共被引关系的特殊引用结构,具有较高的研究价值与拓展意义。为了解同一篇文章在三角引用中不同位置的表现,提出正向三角引用、双向三角引用和逆向三角引用。以Web of Science核心合集数据库中LIS学科作为数据来源,从存在概率、数据特征、引用时间、跨语言引用、跨学科引用、文献类型和作者自引等方面分析了三种三角引用。研究发现,三种三角引用各有特点,在文献类型和作者自引中,三种三角引用表现一致;在存在概率、文献数量特征,以及引用时间、跨语言引用和跨学科引用上存在区别。此外,三角引用结构结合文本相似度与耦合引用强度为分析文献漏引与非相关引用提供了可能。展开更多
The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservo...The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservoirs in the Cretaceous Qingshuihe Formation in the Gaoquan structure of the Sikeshu Sag, southern Junggar Basin were analyzed. On this basis, the thermal history was calibrated using calcite in-situ U-Pb dating and fluid inclusion analysis to depict the hydrocarbon accumulation process in the Gaoquan structure. The results show that the Qingshuihe reservoir experienced two phases of calcite cementation and three phases of hydrocarbon charging. The calcite cements are dated to be (122.1±6.4) Ma, (14.4±1.0) Ma - (14.2±0.3) Ma. The hydrocarbon charging events occurred at around 14.2-30.0 Ma (low-mature oil), 14.2 Ma (mature oil), and 2 Ma (high-mature gas). The latter two phases of hydrocarbon charging contributed dominantly to the formation of reservoir. Due to the S-N compressive thrust activity during the late Himalayan period since 2 Ma, the traps in the Gaoquan structure were reshaped, especially the effective traps which developed in the main reservoir-forming period were decreased significantly in scale, resulting in weak hydrocarbon shows in the middle-lower part of the structure. This indicates that the effective traps in key reservoir-forming period controlled hydrocarbon enrichment and distribution in the lower reservoir assemblage. Calcite U-Pb dating combined with fluid inclusion analysis can help effectively describe the complex diagenesis and hydrocarbon accumulation process in the central-west part of the basin.展开更多
文摘情报学术语承载了情报学科基础知识与核心概念。从概念维度梳理与分析情报学术语对推动学科发展、助力下游知识挖掘任务具有重要意义。面对数量快速增长的科技文献,自动术语抽取替代了人工筛选,但现有方法严重依赖大规模标注数据集,难以迁移至低资源场景。本文设计了一种生成式情报学术语抽取方法(generative term extraction for information science,GTX-IS),将传统基于序列标注的抽取式任务转化为序列到序列的生成式任务。结合小样本学习策略与有监督微调,提升面向特定任务的文本生成能力,能够在低资源有标签数据集场景下较为精准地抽取情报学术语。对于抽取结果,本文进一步开展了情报学领域术语发现及多维知识挖掘。综合运用全文科学计量与信息计量方法,从术语自身、术语间关联、时间信息等维度,对术语的出现频次、生命周期、共现信息等进行统计分析与知识挖掘。采用社会网络分析方法,结合时间维度特征,从术语角度出发,完善期刊的动态简介,探究情报学研究热点、演变历程和未来发展趋势。本文方法在术语抽取实验中的表现超越了全部13种主流生成式和抽取式模型,展现出较强的小样本学习能力,为领域信息抽取提供了新的思路。
文摘为合理调节或优化传统钢板剪力墙(steel plate shear wall,SPSW)的抗震性能,本文提出了一种新型的带圆形压痕的钢板剪力墙结构(steel plate shear wall with circle dents,SPSW-CD)。基于有限元方法系统研究了压痕孔径、压痕孔距、压痕深度、钢板厚度和钢材强度等参数对SPSW-CD抗侧性能的影响,提出了四边连接SPSW-CD抗侧刚度及水平承载力的简化计算公式。分析结果表明随着压痕孔径增加,SPSW-CD的初始抗侧刚度及水平承载力均呈降低趋势;压痕孔距及钢板厚度越大,SPSW-CD抗侧性能越优。随着钢材强度增加,SPSW-CD水平承载力呈明显的增大趋势,但对其抗侧刚度影响不明显。压痕深度对SPSW-CD抗侧性能的影响可忽略。SPSW-CD抗侧刚度及水平承载力计算公式计算误差均小于10%,研究成果可用于此类结构的工程设计。
文摘三角引用是一种融合直接引用关系、耦合关系和共被引关系的特殊引用结构,具有较高的研究价值与拓展意义。为了解同一篇文章在三角引用中不同位置的表现,提出正向三角引用、双向三角引用和逆向三角引用。以Web of Science核心合集数据库中LIS学科作为数据来源,从存在概率、数据特征、引用时间、跨语言引用、跨学科引用、文献类型和作者自引等方面分析了三种三角引用。研究发现,三种三角引用各有特点,在文献类型和作者自引中,三种三角引用表现一致;在存在概率、文献数量特征,以及引用时间、跨语言引用和跨学科引用上存在区别。此外,三角引用结构结合文本相似度与耦合引用强度为分析文献漏引与非相关引用提供了可能。
基金Supported by PetroChina Science and Technology Development Project(2023ZZ0206,2021DJ0303,2021DJ0105,2021DJ0203)National Natural ScienceFoundation of China(U22B6002).
文摘The complexity of diagenesis and hydrocarbon accumulation in the deep reservoirs in southern Junggar Basin restricts hydrocarbon exploration in the lower reservoir assemblage. The lithofacies and diagenesis of reservoirs in the Cretaceous Qingshuihe Formation in the Gaoquan structure of the Sikeshu Sag, southern Junggar Basin were analyzed. On this basis, the thermal history was calibrated using calcite in-situ U-Pb dating and fluid inclusion analysis to depict the hydrocarbon accumulation process in the Gaoquan structure. The results show that the Qingshuihe reservoir experienced two phases of calcite cementation and three phases of hydrocarbon charging. The calcite cements are dated to be (122.1±6.4) Ma, (14.4±1.0) Ma - (14.2±0.3) Ma. The hydrocarbon charging events occurred at around 14.2-30.0 Ma (low-mature oil), 14.2 Ma (mature oil), and 2 Ma (high-mature gas). The latter two phases of hydrocarbon charging contributed dominantly to the formation of reservoir. Due to the S-N compressive thrust activity during the late Himalayan period since 2 Ma, the traps in the Gaoquan structure were reshaped, especially the effective traps which developed in the main reservoir-forming period were decreased significantly in scale, resulting in weak hydrocarbon shows in the middle-lower part of the structure. This indicates that the effective traps in key reservoir-forming period controlled hydrocarbon enrichment and distribution in the lower reservoir assemblage. Calcite U-Pb dating combined with fluid inclusion analysis can help effectively describe the complex diagenesis and hydrocarbon accumulation process in the central-west part of the basin.
