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基于主题过滤和因果推断的社交媒体转发机制分析

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系统科学与数学 2024年第6期44卷 1534-1549页

作者：黄晓辉闫志华唐锡晋中国科学院数学与系统科学研究院北京100190 中国科学院大学北京100049 山西财经大学管理科学与工程学院太原030006

知悉社交媒体平台中影响信息转发的主要因素对于危害信息扩散的管控有着重要的意义,以往研究大多基于回归分析的方法,挖掘对转发数存在显著影响的变量,在可解释性上存在不足.文章基于统计回归建模和因果推断方法,从用户特征和文本特征... 详细信息

知悉社交媒体平台中影响信息转发的主要因素对于危害信息扩散的管控有着重要的意义,以往研究大多基于回归分析的方法,挖掘对转发数存在显著影响的变量,在可解释性上存在不足.文章基于统计回归建模和因果推断方法,从用户特征和文本特征分析影响推文转发的变量,并生成解释文本情绪与转发数因果关系的剂量-效应函数.此外,考虑到社交媒体观测数据集采集时存在收集偏差的问题,文章使用主题聚类方法进行数据过滤.在对疫苗讨论和总统选举Twitter数据集的实证分析中,该研究发现了显著影响信息转发的变量集,以及文本情绪对于转发数的因果效应.

关键词：因果推断主题过滤泊松回归信息扩散

Narrative Graph:Telling Evolving Stories Based on Event-centric Temporal Knowledge Graph

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Journal of Systems Science and Systems Engineering 2023年第2期32卷 206-221页

作者： zhihua yan Xijin Tang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China School of Management Science and Engineering Shanxi University of Finance and EconomicsTaiyuan030006China University of Chinese Academy of Sciences Beijing100039China

As the main channel for people to obtain information and express their opinions,online media generate a huge amount of unstructured news documents every day and make it difficult for people to perceive major societal events and grasp the evolution of *** studies on storyline generation are generally based on document clustering without considering event arguments and relations between ***-centric knowledge graph has been used to facilitate the construction of news documents to form structured event *** some studies have attempted to construct timelines based on event-centric knowledge graphs,it is difficult for timelines to depict the complex structures of event *** this paper,we try to represent news documents as an event-centric knowledge graph,and compress the whole knowledge graph into salient complex events in temporal order to generate storylines named narrative *** first collect news documents from news platforms,construct an event ontology,and build an event-centric knowledge graph with temporal *** neural network is used to detect events,while BERT fine-tuning is leveraged to identify temporal relations between ***,a novel generation framework of narrative graph with constraints of coherence and coverage is *** addition,a case study is implemented to demonstrate how to utilize narrative graph to analyze real-world *** experiment results show that our approach significantly outperforms the baseline approaches.

关键词： Storyline event-centric knowledge graph event evolution community detection

贵州省煤层气井压裂改造对产气量的影响及开发建议——以盘关向斜为例

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煤炭科学技术 2024年第S1期52卷 116-126页

作者：胡海洋颜智华娄毅杜志刚李全中陈捷高为贵州省煤层气页岩气工程技术研究中心贵州贵阳550081 贵州省煤田地质局地质勘察研究院贵州贵阳550081 贵州省煤炭流态化开采重点实验室贵州贵阳550014 中国矿业大学资源与地球科学学院江苏徐州221008 贵州盘江煤层气开发利用有限责任公司贵州贵阳550081 洛阳理工学院土木工程学院河南洛阳471023 山西工程技术学院矿业工程系山西阳泉045000

贵州省含煤构造单元多、煤层层数多、厚度薄,多为低渗储层,宜采取“分段压裂、合层排采”工艺进行煤层气开发。研究以盘关向斜煤层气井为例,在分析2口直井压裂改造规模的基础上,分析其压裂效果,进而研究了压裂改造效果对煤层气井气水产... 详细信息

贵州省含煤构造单元多、煤层层数多、厚度薄,多为低渗储层,宜采取“分段压裂、合层排采”工艺进行煤层气开发。研究以盘关向斜煤层气井为例,在分析2口直井压裂改造规模的基础上,分析其压裂效果,进而研究了压裂改造效果对煤层气井气水产出的影响,最后总结了盘关向斜煤层气井高效改造压裂施工参数的合理阈值。结果表明:水力压裂是低渗储层增渗的有效途径,增渗倍数与压裂改造规模密切相关,盘关向斜2口井每米煤层的加砂量、加液量及单孔排量的差异,导致压裂改造后与改造前的渗透率比值为55∶1,改造后渗透率差异较大;提高每米煤层的加液量、加砂量及单孔排量,对提高煤层的改造效果及产气量有利,建议每米煤层加液量不宜低于400 m^(3),每米煤层加砂量不宜低于20 m^(3),压裂施工排量不低于8 m^(3)/min,且单孔排量宜控制在0.2 m^(3)/min以上;根据压裂改造后的煤层渗透率,针对改造效果好的煤层气井,可以适当快排降压,反之则应控制排采强度,降低快排降压可能引起的储层敏感性伤害。研究成果可以为该区块低渗煤层增渗增能改造提供技术参考。

关键词：煤层气井分层压裂排采控制气水产出开发建议

谷氨酰胺对甲状腺癌细胞恶性生物学行为及SNX10/mTORC1通路相关蛋白表达的影响

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郑州大学学报（医学版） 2024年第4期59卷 544-548页

作者：闫志华程兵陈伟娜李祥周郑州大学第一附属医院核医学科郑州450052

目的:探究谷氨酰胺(Gln)对甲状腺癌细胞恶性生物学行为及SNX10/mTORC1通路蛋白表达的影响。方法:分别用含0、1、2、4 mmol/L Gln的培养基培养人未分化甲状腺癌细胞系C643,每个浓度设6个复孔。分组培养24、48、72 h后,MTT法检测细胞增殖... 详细信息

目的:探究谷氨酰胺(Gln)对甲状腺癌细胞恶性生物学行为及SNX10/mTORC1通路蛋白表达的影响。方法:分别用含0、1、2、4 mmol/L Gln的培养基培养人未分化甲状腺癌细胞系C643,每个浓度设6个复孔。分组培养24、48、72 h后,MTT法检测细胞增殖活性。分组培养24 h后,采用Annexin V/PI双染法、划痕实验、Transwell小室实验、三磷酸腺苷(ATP)实验检测细胞凋亡率、迁移能力、侵袭能力、ATP生成能力,采用实时荧光定量PCR法检测SNX10、p-mTOR、mTORC1 mRNA的表达,Western blot法检测SNX10、p-mTOR、mTORC1、Akt、p-Akt蛋白的表达。结果:Gln干预后,C643细胞凋亡率下降,增殖活性、划痕愈合率、侵袭细胞数、ATP浓度均增加,SNX10、p-mTOR、mTORC1 mRNA相对表达量升高,SNX10、p-mTOR、mTORC1、Akt、p-Akt蛋白表达上调,且均呈剂量依赖性(P<0.05)。结论:Gln可能通过激活SNX10/mTORC1通路而促进甲状腺癌细胞的恶性生物学行为。

关键词：甲状腺癌谷氨酰胺代谢 SNX10/mTORC1通路

A note on the uniqueness theorem of meromorphic mappings

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Science China Mathematics 2006年第3期49卷 360-365页

作者： yan Qiming CHEN zhihua Department of Mathematics Tongji University Shanghai 200092 China Department of Mathematics Tongji University Shanghai 200092 China

In this article, some uniqueness theorems of meromorphic mappings are proved.

关键词： value distribution theory, uniqueness theorem, meromorphic mappings.

Exploring Evolution of Public Opinions on Tianya Club Using Dynamic Topic Models

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Journal of Systems Science and Information 2020年第4期11卷 309-324页

作者： zhihua yan Xijin TANG Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Online media have brought tremendous changes to civic life, public opinions, and government administration. Compared with traditional media, online media not only allow individuals to browse news and express their views more freely, but also accelerate the transmission of opinions and expand influence. As public opinions may arouse societal unrest, it is worth detecting the primary topics and uncovering the evolution trends of public opinions for societal administration. Various algorithms are developed to deal with the huge volume of unstructured online media data. In this study,dynamic topic model is employed to explore topic content evolution and prevalence evolution using the original posts published from 2013 to 2017 on the Tianya Zatan Board of Tianya Club, which is one of the most popular BBS in China. Based on semantic similarities, topics are grouped into three themes: Family life, societal affairs, and government administration. The evolution of topic prevalence and content are affected by emergent incidents. Topics on family life become popular, while themes"societal affairs" and "government administration" with bigger standard deviations are more likely to be influenced by emergent hot events. Content evolution represented by monthly pairwise distance matrix is very easy to find change points of topic content.

关键词： likely administration Topic

SOLED STATE AMORPHIZATION REACTION REACTION UNDER HIGH PRESSURE

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Chinese Physics Letters 1989年第4期6卷 173-176页

作者： yan zhihua LI Jinfeng WANG Wenkui Institute of Physics Academia SinicaBeijing Depax tment of Mat erial Science Jilin UniversityJilin

The solid state reaction of Nigo Tigo multilayer under high pressure was carried out to investigate the effect of pressure on the amorphization *** the pressure of BOkbars amorphization reaction could not occur at 250℃while amorphous phase formed by isothermal annealing at same temperature in vacuum as well as lower *** is suggested that the effect of pressure on diffusion played a predominant role,and Ni atom should diffuse into Ti layers with vacancy mechanism rather than interstitial one.

关键词： process annealing amorphous

@AMORPHOUS Ni50Ti50 FILM FORMED BY SOLID-STATE REACTION

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Chinese Physics Letters 1987年第12期4卷 569-571页

作者： yan zhihua WANG Wenkui Institute of Physics Academy SinicaBeijing

The solid-state reaction technique has been used to form the amorphous Ni_(50)Ti_(50) *** alternative layers were prepared by an electron beam evaporating *** amorphization was determined by means of X-ray diffraction... 详细信息

关键词： amorphization apparatus amorphous

两种不同剂量碘-131对非远处转移性高危分化型甲状腺癌全切术后患者DTC的应用效果

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实用癌症杂志 2024年第1期39卷 102-105页

作者：闫志华程兵李祥周陈伟娜郑州大学第一附属医院 450000

目的探讨两种不同剂量碘-131对非远处转移性高危分化型甲状腺癌(DTC)全切术后患者的应用效果。方法回顾性分析86例非远处转移性高危DTC患者的临床资料,所有患者均行DTC全切术,并按照碘-131治疗剂量的不同分成低剂量组(100~150 mCi)和高... 详细信息

目的探讨两种不同剂量碘-131对非远处转移性高危分化型甲状腺癌(DTC)全切术后患者的应用效果。方法回顾性分析86例非远处转移性高危DTC患者的临床资料,所有患者均行DTC全切术,并按照碘-131治疗剂量的不同分成低剂量组(100~150 mCi)和高剂量组(150~200 mCi),前者为45例,后者为41例,治疗3个月,随访1年。比较两组相关临床治疗指标(清甲成功率、无病生存率、住院隔离时间)、甲状腺癌特异性生命质量量表(THYCA-QoL)和不良反应发生情况的差异。结果治疗及随访结束后,两组的清甲成功率无明显差异(P<0.05),低剂量组的无病生存率(95.56%)高于高剂量组(80.49%),且住院隔离时间短于高剂量组(P<0.05);两组生理功能和活动、心理功能、症状或对生活影响评分均高于同组治疗前,且低剂量组THYCA-QoL评分均高于高剂量组(P<0.05);低剂量组不良反应发生率(8.89%)低于高剂量组(29.27%)(P<0.05)。结论低剂量和高剂量碘-131对于非远处转移性高危DTC全切术后患者的治疗效果相当,但前者更有利于缩短住院隔离时间,提高无病生存率,减少不良反应的发生,进而提高生存质量。

关键词：碘-131 不同剂量非远处转移性分化型甲状腺癌甲状腺全切术