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Communications in Theoretical Physics 2023年第2期75卷 46-55页

作者： Fei-Yan Liu yi-tian gao Ministry-of-Education Key Laboratory of Fluid Mechanics and National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191China

In this paper,we investigate a(2+1)-dimensional variable-coefficient modified dispersive waterwave system in fluid *** prove the Painlevéintegrability for that system via the Painlevé*** find some auto-B?cklund transformations for that system via the truncated Painlevé*** forms and N-soliton solutions are constructed,where N is a positive *** discuss the inelastic interactions,elastic interactions and soliton resonances for the two *** also graphically demonstrate that the velocities of the solitons are affected by the variable coefficient of that system.

关键词： fluid mechanics variable-coefficient modified dispersive water-wave system Painlevéanalysis bilinear forms soliton solutions auto-Bäcklund transformations

Solitons and periodic waves for a generalized(3+1)-dimensional Kadomtsev-Petviashvili equation in fluid dynamics and plasma physics

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Communications in Theoretical Physics 2020年第11期72卷 30-36页

作者： Dong Wang yi-tian gao Cui-Cui Ding Cai-yin Zhang Ministry-of-Education Key Laboratory of Fluid Mechanics and National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191China

Under investigation in this paper is a generalized(3+1)-dimensional Kadomtsev-Petviashvili equation in fluid dynamics and plasma *** and one-periodic-wave solutions are obtained via the Hirota bilinear method and Hirota-Riemann *** and velocity of the one soliton are *** are presented to discuss the solitons and one-periodic waves:the coefficients in the equation can determine the velocity components of the one soliton,but cannot alter the soliton magnitude;the interaction between the two solitons is elastic;the coefficients in the equation can influence the periods and velocities of the periodic *** between the one-soliton solution and one-periodic wave solution is investigated.

关键词： fluid dynamics plasma physics generalized(3+1)-dimensional Kadomtsev-Petviashvili equation solitons periodic waves

Procedural generation and real-time rendering of a marine ecosystem

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第7期15卷 514-524页

作者： Rong LI Xin DING Jun-hao YU tian-yi gao Wen-ting ZHENG Rui WANG Hu-jun BAO State Key Lab of CAD & CG Zhejiang University PLA Unit 61741

Underwater scene is one of the most marvelous environments in the world. In this study, we present an efficient procedural modeling and rendering system to generate marine ecosystems for swim-through graphic applications. To produce realistic and natural underwater scenes, several techniques and algorithms have been presented and introduced. First, to distribute sealife naturally on a seabed, we employ an ecosystem simulation that considers the influence of the underwater environment. Second, we propose a two-level procedural modeling system to generate sealife with unique biological features. At the base level, a series of grammars are designed to roughly represent underwater sealife on a central processing unit(CPU). Then at the fine level, additional details of the sealife are created and rendered using graphic processing units(GPUs). Such a hybrid CPU-GPU framework best adopts sequential and parallel computation in modeling a marine ecosystem, and achieves a high level of ***, the proposed system integrates dynamic simulations in the proposed procedural modeling process to support dynamic interactions between sealife and the underwater environment, where interactions and physical factors of the environment are formulated into parameters and control the geometric generation at the fine level. Results demonstrate that this system is capable of generating and rendering scenes with massive corals and sealife in real time.

关键词： Procedural generation Marine ecosystem Biological feature Graphic processing unit acceleration

Review of precipitation strengthening in ultrahigh-strength martensitic steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 256-269页

作者： Zhihao tian Chunlei Shang Chaolei Zhang Xiaoye Zhou Honghui Wu Shuize Wang Guilin Wu Junheng gao Jiaming Zhu Xinping Mao Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110004China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen 518172China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China School of Civil Engineering Shandong UniversityJinan 250061China

Martensite is an important microstructure in ultrahigh-strength steels,and enhancing the strength of martensitic steels often involves the introduction of precipitated phases within the martensitic *** considerable research efforts devoted to this area,a systematic summary of these advancements is *** review focuses on the precipitates prevalent in ultrahigh-strength martensitic steel,primarily carbides(e.g.,MC,M_(2)C,and M_(3)C)and intermetallic compounds(e.g.,Ni Al,Ni_(3)X,and Fe_(2)Mo).The precipitation-strengthening effect of these precipitates on ultrahigh-strength martensitic steel is discussed from the aspects of heat treatment processes,microstructure of precipitate-strengthened martensite matrix,and mechanical ***,a perspective on the development of precipitation-strengthened martensitic steel is presented to contribute to the advancement of ultrahigh-strength martensitic *** review highlights significant findings,ongoing challenges,and opportunities in the development of ultrahigh-strength martensitic steel.

关键词： ultrahigh-strength martensitic steel precipitation strengthening mechanical property carbide intermetallic compound

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关联并购的并购绩效研究——基于现金流视角

经济问题 2017年第5期 110-116页

作者：王一棣田高良韩洁天津大学管理与经济学部天津300072 西安交通大学管理学院西安710049 西北大学经济管理学院陕西西安710127

在中国企业中,关联并购现象非常普遍。与公允并购相比,发生在上市公司和其关联方之间的并购交易的并购价值更高还是更低?基于现金流视角,以中国A股上市公司的并购事件作为样本,通过实证检验发现:关联并购的并购绩效显著低于公允并购;与... 详细信息

在中国企业中,关联并购现象非常普遍。与公允并购相比,发生在上市公司和其关联方之间的并购交易的并购价值更高还是更低?基于现金流视角,以中国A股上市公司的并购事件作为样本,通过实证检验发现:关联并购的并购绩效显著低于公允并购;与非国有企业相比,当并购方是国有企业时,关联并购的并购方并购绩效更低。最后,我们将相对并购价值分为两部分:正常部分和非正常部分,发现非正常部分对并购绩效有着显著的负向影响。可见,关联并购损害了并购公司的股东价值。

关键词：关联并购国有企业自由现金流假说

A variable-coefficient unstable nonlinear Schrdinger model for the electron beam plasmas and Rayleigh-Taylor instability in non-uniform plasmas: Solutions and observable effects

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A variable-coefficient unstable nonlinear Schrdinger model...

2003’全国流体力学青年研讨会

作者： yi-tian gao and Bo tian School of Aeronautic Science and Technology,Beijing University of Aeronautics and Astronautics,Beijing 100083,China School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,China

＜正＞ A variable-coefficient unstable nonlinear Schrodinger model is hereby investigated, which arises in such applications as the electron-beam plasma waves and Rayleigh-Taylor instability in non-uniform, plasmas. With computerized symbolic computation, families of exact analytic dark- and bright-soliton-like solutions are found, along with similarity solutions. Some observable effects caused by the variable coefficient are predicted, which may be detected in the future with the relevant space or laboratory plasma experiments with non-uniform background existing. The full text of this paper will appear in Phys. Plasmas, Vol. 10, Iss. 11, Nov., 2003.

关键词： Variable-coefficient unstable nonlinear Schrodinger model Electron beam plasmas Rayleigh-Taylor instability Non-uniform plasmas Analytic soliton-like solutions Similarity solutions Observable effects

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泥沙污染水质模型研究

四川大学学报（工程科学版） 2004年第6期36卷 12-17页

作者：何用李义天郜会彩王家生武汉大学水资源与水电工程国家重点实验室湖北武汉430072

多数污染物的迁移转化与泥沙和泥沙运动关系紧密,将水相和悬浮相污染作为一个整体,结合泥沙模型,引入泥沙污染物吸附量,底泥释放量及冲淤引起的释放增量等物理量,推导建立了泥沙污染水质模型,并运用吸附动力学,孔隙水扩散等模型,解决了... 详细信息

多数污染物的迁移转化与泥沙和泥沙运动关系紧密,将水相和悬浮相污染作为一个整体,结合泥沙模型,引入泥沙污染物吸附量,底泥释放量及冲淤引起的释放增量等物理量,推导建立了泥沙污染水质模型,并运用吸附动力学,孔隙水扩散等模型,解决了泥沙吸附量和底泥的释放随时空变化的问题。模型较完整地考虑了泥沙输移、底泥冲刷及释放等过程对水质的影响。应用于汉阳四湖调水工程中,结果表明模型精度较高,能体现泥沙对水质的影响。

关键词：水质模型吸附解吸冲刷底泥释放

Association of Genetic Polymorphisms in the LncRNAs with Gastric Cancer Risk in a Chinese Population

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Association of Genetic Polymorphisms in the LncRNAs with Gas...

2017年中国肿瘤标志物学术大会暨第十一届肿瘤标志物青年科学家论坛

作者： Bang-Shun He Hui-Ling Sun Tao Xu Yu-Qin Pan Kang Lin tian-yi gao Zhen-Yu Zhang Shu-Kui Wang General Clinical Research Center Nanjing First HospitalNanjing Medical University Department of Laboratory Medicine Nanjing First HospitalNanjing Medical University Department of Gastroenterology Nanjing First HospitalNanjing Medical University

Background: Genome-wide association studies have identified that polymorphisms in 8 q24 confer susceptibility to gastric cancer. Polymorphisms in the lncRNA PRNCR1, PCAT1, and CCAT2 transcribed from the 8 q24 locus have a potential risk for gastric cancer. Methods: To evaluate whether there is such an association in Chinese population, a case-control study enrolled 494 patients and 494 healthy controls was carried out. Sequenom MassARRAY platform was used for genotyping. Results: This study showed that rs16901946 G allele was associated with increased risk of gastric cancer(AG: adjusted OR = 1.33, 95% CI =1.02-1.73, p=0.033;GG: adjusted OR = 2.07;95% CI = 1.11-3.86, p=0.023, AG/GG: adjusted OR = 1.39, 95% CI = 1.08-1.1.79, p=0.011;additive model: adjusted OR = 1.37;95% CI = 1.10-1.70, p=0.004). Stratified analysis indicated that the increased risk was more evident in younger subjects(adjusted OR = 1.84, 95% CI = 1.18-2.87, p=0.007), males(adjusted OR = 1.55, 95% CI = 1.15-2.08, p=0.004), positive Helicobacter pylori infection(adjusted OR = 1.44, 95% CI = 1.02-2.03, p=0.041), gastric cardia adenocarcinoma(adjusted OR = 1.61, 95% CI = 1.10-2.35, p=0.014), and tumor stage T1-T2(adjusted OR = 1.58, 95% CI = 1.10-2.28, p=0.013). Conclusions: Out study suggested that rs16901946 G allele carriers have an increased risk of gastric cancer, and the risk could be enhanced by the interactions between the polymorphism and age, sex, Helicobacter pylori infection.

关键词： Gastric cancer polymorphism lncRNA

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用于丙烯气相聚合工艺的NG催化剂的研究

石油化工 2003年第9期32卷 759-762页

作者：王志武李天益高明智谭忠北京化工研究院北京100013

在N催化剂基础上开发了一种适于丙烯气相聚合的NG催化剂 ,并将其与在Amoco气相聚丙烯装置使用的同类进口催化剂在颗粒形态、组成及聚合动力学行为、催化活性、定向性、氢调敏感性及共聚性能等方面进行了比较 ,结果表明。

关键词： NG催化剂聚丙烯气相聚合工艺丙烯

Association of genetic polymorphisms in the nucleotide excision repair pathway geneswith breast cancer risk in a Chinese population

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Association of genetic polymorphisms in the nucleotide excis...