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Geometry Theorem Proving by Decomposing Polynomial System into Strong Regular Sets

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Journal of Computer Science & Technology 2004年第6期19卷 820-827页

作者： yong-BinLi WuLiu] xiao-LinXiang MathematicalCollege SichuanUniversityChengdu610031P.R.China DepartmentofComputerScienceandTechnology SichuanAgricultureUniversityDujiangyan611830P.R.China

This paper presents a complete method to prove geometric theorem by decomposing the corresponding polynomial system. into strong regular sets, by which one can compute some components for which the geometry theorem is true and exclude other components for which the geometry theorem is false. Two examples are given to show that the geometry theorems are conditionally true for some components which are excluded by other methods.

关键词： zero decomposition strong regular set automated geometry theorem proving subsidiary condition

Formation Mechanism of the Paleocene Basal Conglomerate,Southwest Tarim Basin

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Journal of Earth Science 2024年第5期35卷 1513-1526页

作者： yong Yue Jingchun tian Chuanyan Huang Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Shanghai Branch of CNOOC Ltd. Shanghai 200335China Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationFaculty of Earth ResourcesChina University of GeosciencesWuhan 430074China

Most knowledge about the Cretaceous-Paleogene strata in the Tarim Basin is mainly inferred from the outcrops at the basin's margin,but first time in the *** formation mechanism of the Paleocene basal conglomerate was determined using geochemical isotopes of the breccia from Well PBX1 in the southwestern Tarim *** results showed that the global K/Pg(i.e.,Cretaceous/Paleogene)clay layer boundary was located in the middle of the Paleocene basal conglomerate at the depth of 7066.75 m in Well *** the Late Cretaceous,associated with volcanic activities and earthquakes,the caldera in the Well PBX1 Block formed an annular depression with large elevation differences in response to the Pamir Block *** a result,the collapsed breccia with storm tide genesis deposited at the periphery and inside of the depression,characterized by syn-sedimentary *** the Paleocene,multiple sets of interbedded carbonate and collapsed breccia deposited in response to multi-phased transient transgression-regression *** transportation of breccia exhibited near-source accumulation/extremely close or in-situ rapid *** studied region is located in the eastern end of the Tethys Sea,the Late Cretaceous-Early Paleocene breccia is of great significance for reconstructing the paleogeography of the Tarim basin in Tethys.

关键词： South-Western Tarim Paleogene system Breccia Attribution and genesis petroleum geology

Time-Domain Higher-Order Boundary Element Method for Simulating High Forward-Speed Ship Motions in Waves

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China Ocean Engineering 2024年第5期38卷 904-914页

作者： ZHOU xiao-guo CHENG yong PAN Su-yong School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

The hydrodynamic performance of a high forward-speed ship in obliquely propagating waves is numerically examined to assess both free motions and wave field in comparison with a low forward-speed *** numerical model is based on the time-domain potential flow theory and higher-order boundary element method,where an analytical expression is completely expanded to determine the base-unsteady coupling flow imposed on the moving condition of the *** ship in the numerical model may possess different advancing speeds,***,low speed,and high *** role of the water depth,wave height,wave period,and incident wave angle is analyzed by means of the accurate numerical *** is found that the resonant motions of the high forward-speed ship are triggered by comparison with the stationary *** specifically,a higher forward speed generates a V-shaped wave region with a larger elevation,which induces stronger resonant motions corresponding to larger wave *** shoaling effect is adverse to the motion of the low-speed ship,but is beneficial to the resonant motion of the high-speed *** waves obliquely propagate toward the ship,the V-shaped wave region would be broken due to the coupling effect between roll and pitch *** is also demonstrated that the maximum heave motion occurs in beam seas for stationary cases but occurs in head waves for high ***,the variation of the pitch motion with period is hardly affected by wave incident angles.

关键词： high forward speed oblique incident waves ship motion higher-order boundary element method time domain wave field

Endothelial Cell Senescence and Age-Related Vascular Diseases

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Journal of Genetics and Genomics 2014年第9期41卷 485-495页

作者： xiao-Li tian Yang Li Department of Human Population Genetics and Beijing Key Laboratory of Cardiometabolic Molecular Medicine Institute of Molecular Medicine(IMM)Peking University

Advanced age is an independent risk factor for ageing-related complex diseases, such as coronary artery disease, stroke, and hypertension, which are common but life threatening and related to the ageing-associated vascular dysfunction. On the other hand, patients with progeria syndromes suffer from serious atherosclerosis, suggesting that the impaired vascular functions may be critical to organismal ageing, or vice versa. However, it remains largely unknown how vascular cells, particularly endothelial cell, become senescent and how the senescence impairs the vascular functions and contributes to the age-related vascular diseases over time. Here, we review the recent progress on the characteristics of vascular ageing and endothelial cell senescence in vitro and in vivo, evaluate how genetic and envi- ronmental factors as well as autophagy and stem cell influence endothelial cell senescence and how the senescence contributes to the age- related vascular phenotypes, such as atherosclerosis and increased vascular stiffness, and explore the possibility whether we can delay the age-related vascular diseases through the control of vascular ageing.

关键词： Endothelial cell senescence Genetic Vascular ageing Age-related diseases Stem cell

Experimental primates and non-human primate(NHP) models of human diseases in China: current status and progress

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Zoological Research 2014年第6期35卷 447-464页

作者： xiao-Liang ZHANG Wei PANG Xin-tian HU Jia-Li LI yong-Gang YAO yong-Tang ZHENG Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences Faculty of Life Science and Technology Kunming University of Science and Technology Kunming Primate Research Center of the Chinese Academy of Sciences Kunming Institute of Zoology Chinese Academy of Sciences

Non-human primates （NHPs） are phylogenetically close to humans, with many similarities in terms of physiology, anatomy, immunology, as well as neurology, all of which make them excellent experimental models for biomedical research. Compared with developed countries in America and Europe, China has relatively rich primate resources and has continually aimed to develop NHPs resources. Currently, China is a leading producer and a major supplier of NHPs on the international market. However, there are some deficiencies in feeding and management that have hampered China＇s growth in NHP research and materials. Nonetheless, China has recently established a number of primate animal models for human diseases and achieved marked scientific progress on infectious diseases, cardiovascular diseases, endocrine diseases, reproductive diseases, neurological diseases, and ophthalmic diseases, etc. Advances in these fields via NHP models will undoubtedly further promote the development of China＇s life sciences and pharmaceutical industry, and enhance China＇s position as a leader in NHP research. This review covers the current status of NHPs in China and other areas, highlighting the latest developments in disease models using NHPs, as well as outlining basic problems and proposing effective to better utilize NHP resources and further foster NHP research in China.

关键词： Non-human primates Experimental primates Animal models Current status

New Families of Rational Form Variable Separation Solutions to(2+1)-Dimensional Dispersive Long Wave Equations

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Communications in Theoretical Physics 2009年第5期51卷 789-793页

作者： WEN xiao-yong Department of Mathematics College of Sciences Beijing Information Science and Technology University Beijing 100192China

With the aid of symbolic computation system Maple, some families of new rational variable separation solutions of the （2＋1）-dimensional dispersive long wave equations are constructed by means of a function transformation, improved mapping approach, and variable separation approach, among which there are rational solitary wave solutions, periodic wave solutions and rational wave solutions.

关键词： improved mapping approach variable separation method (2+1)-dimensional dispersive long wave equations symbolic computation

Ant colony optimization for assembly sequence planning based on parameters optimization

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Frontiers of Mechanical Engineering 2021年第2期16卷 393-409页

作者： Zunpu HAN yong WANG De tian Renewable Energy School North China Electric Power UniversityBeijing 102206China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China

As an important part of product design and manufacturing, assembly sequence planning (ASP) has a considerable impact on product quality and manufacturing costs. ASP is a typical NP-complete problem that requires effective methods to find the optimal or near-optimal assembly sequence. First, multiple assembly constraints and rules are incorporated into an assembly model. The assembly constraints and rules guarantee to obtain a reasonable assembly sequence. Second, an algorithm called SOS-ACO that combines symbiotic organisms search (SOS) and ant colony optimization (ACO) is proposed to calculate the optimal or near-optimal assembly sequence. Several of the ACO parameter values are given, and the remaining ones are adaptively optimized by SOS. Thus, the complexity of ACO parameter assignment is greatly reduced. Compared with the ACO algorithm, the hybrid SOS-ACO algorithm finds optimal or near-optimal assembly sequences in fewer iterations. SOS-ACO is also robust in identifying the best assembly sequence in nearly every experiment. Lastly, the performance of SOS-ACO when the given ACO parameters are changed is analyzed through experiments. Experimental results reveal that SOS-ACO has good adaptive capability to various values of given parameters and can achieve competitive solutions.

关键词： assembly sequence planning ant colony optimization symbiotic organisms search parameter optimization

Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： Hui-Wen Pang Han-Qing Wang Yi-tian xiao Yan Jin Yun-Hu Lu yong-Dong Fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

Graphene oxide effects on the properties of Al2O3-Cu/35W5Cr composite

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Journal of Materials Science & Technology 2020年第2期37卷 185-199页

作者： xiaohui Zhang Yi Zhang Baohong tian Yanlin Jia Ming Fu yong Liu Kexing Song AlexAVolinsky xiao Yang Hang Sun School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Collaborative Innovation Center of Nonferrous Metals Henan ProvinceLuoyang 471023China Henan Key Laboratory of Nonferrous Materials Science and Processing Technology Luoyang 471023China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China China Airborne Missile Academy Luoyang 471023China Department of Mechanical Engineering University of South FloridaTampa 33620USA Luoyang Ship Material Research Institute Luoyang 471023China

Graphene oxide(GO)nanosheets were dispersed into premixed powders(Cu-0.4 wt%Al/35W5Cr)by wet grinding and vacuum freeze-drying *** 0.3 wt%GO/Al2O3-Cu/35W5Cr and 0.5 wt%GO/Al2O3-Cu/35W5Cr composites,used for electrical contacts,were fabricated by vacuum hot-pressing *** microstructure was analyzed by field emission scanning electron and transmission electron *** addition,the Raman spectroscopy and X-ray photoelectron spectroscopy were used to investigate the structural changes of GO before and after *** arc erosion behavior was investigated by the JF04 C electrical contact testing ***,the Al2O3 nanoparticles were evenly dispersed in the matrix,causing dislocation *** was converted to reduced graphene oxide after sintering.A group of carbon atoms combined with Cr forming Cr3C2 in situ during sintering,which enhanced the interface *** with the Al2O3-Cu/35W5Cr composite,the tensile strength of the two contact materials containing 0.3 wt%GO and 0.5 wt%GO was increased by 45%and 34%,***,pips and craters were present on the anode and cathode surfaces,*** has undergone re-sintering during arcing and formed needle-like *** with Al2O3-Cu/35W5Cr,the GO/Al2O3-Cu35W5Cr composites have better welding *** final mass transfer direction of the two composites was from the cathode to anode.

关键词： Graphene oxide Freeze-drying Electrical contact In situ formed Cr3C2 Tensile strength