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Pore pressure built-up in hydrate-bearing sediments during phase transition: A poromechanical approach

Petroleum Science 2023年第1期20卷 482-494页

作者： shui-tao Zhang Lin-Lin Wang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China Department of Offshore Oil and Gas Engineering College of Safety and Ocean EngineeringChina University of Petroleum(Beijing)Beijing102249China

Due to the density contrast between the hydrate and methane gas,the pore pressure is accumulated in the sediment during the decomposition process of methane *** accumulation of pore pressure decreases the magnitude of effective stress,further triggering potential geological disasters such as *** paper establishes a theoretical framework to investigate the evolution of fluid pressure in the hydrate-bearing sediments during the decomposition *** model consists of two parts:an unsaturated thermo-poromechanical constitutive law as well as a phase equilibrium *** with the existing studies,the present work incorporates the effect of pore volume change into the pressure built-up *** addition,the capillary effect is considered,which plays a nontrivial role in fine-grained *** on this model,the evolution of fluid pressure is investigated in undrained *** is shown that four mechanisms mainly contribute to the pressure built-up:the density contrast between decomposing hydrate and producing fluid,the variation of pore volume,the compaction of hydrate due to variation of capillary pressure,and the thermal deformation of pore constituents induced by temperature *** these mechanisms,the density contrast dominates the pore pressure *** the combined effect of these contributions,the evolution of fluid pressure exhibits a strong nonlinearity during the decomposition process and can reach up to dozens of mega ***,this high-level pressure built-up results in a significant tensile strain,yielding potential fracturing of the sediment.

关键词： Methane hydrate Excess fluid pressure Poromechanical Phase equilibrium

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工程测量中三维测绘技术的应用现状及发展前景

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世界有色金属 2024年第9期 142-144页

作者：刘欣悦向玉楚水滔湖南省自然资源事务中心湖南长沙410000

三维测绘技术已成为工程测量的关键组成部分,其精确的数据收集和处理能力对工程设计、施工和监控产生了深远的影响。技术如摄影测量、遥感、激光雷达、全景扫描以及GPS和GNSS的应用,极大提高了工程测量的效率和精度。随着大数据、云计... 详细信息

三维测绘技术已成为工程测量的关键组成部分,其精确的数据收集和处理能力对工程设计、施工和监控产生了深远的影响。技术如摄影测量、遥感、激光雷达、全景扫描以及GPS和GNSS的应用,极大提高了工程测量的效率和精度。随着大数据、云计算、人工智能和机器学习的融入,三维测绘技术的处理能力和应用范围得到了显著扩展。无人机测绘技术的发展,虽面临技术和法规挑战,但在灵活性和成本效益上展现出巨大潜力。环保测绘的重要性日益凸显,强调了测绘技术在环境监测和资源管理中的作用。

关键词：三维测绘技术工程测量摄影测量遥感技术

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基于Python的房屋安全健康监测数据处理与预测分析

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科学技术与工程 2024年第6期24卷 2469-2479页

作者：孙振林柳飞陶水忠杨晓辉于茜张硕周闯北京市市政工程研究院北京100037 北京市建设工程质量第三检测所有限责任公司北京100037 北京城建勘测设计研究院有限责任公司北京100101

房屋安全问题愈发受到重视,对于老旧房屋的自动化健康监测十分必要。在此背景下,优化自动化监测数据的预处理流程,使用Python丰富的“库”资源构建预处理程序。程序使用灰色关联法对数据进行可信度评估筛选数据,利用箱形图筛选异常数据... 详细信息

房屋安全问题愈发受到重视,对于老旧房屋的自动化健康监测十分必要。在此背景下,优化自动化监测数据的预处理流程,使用Python丰富的“库”资源构建预处理程序。程序使用灰色关联法对数据进行可信度评估筛选数据,利用箱形图筛选异常数据,并对异常数据和缺失数据进行插补替换,最后使用卡尔曼滤波平滑数据以降低数据离散度;自动化监测设备因自身特点易受到周围环境的影响,为此提出了一种利用人工监测数据校核自动化监测数据的数据比对方法,以保证自动化监测数据的准确性和可靠度;最后使用拟合曲线实现变形监测数据的短期预测,预测精度达到0.1%,有效预测时间约10 d,最终的结果满足程序设计需求。

关键词：数据预处理与校核自动化监测短期预测老旧房屋 Python

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Implementation of gastrointestinal function protection in severe acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 521-522页

作者： Fu-Zheng tao Rong-Lin Jiang shui-Fang Jin Intensive Care Unit Taizhou Integrated Traditional Chinese and Western Medicine HospitalTaizhou 310075China Intensive Care Unit the First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006China

Severe acute pancreatitis(SAP)is a serious systemic disease associated with strong local inflammatory reactions and serious systemic pathophysiological disorders caused by trypsin *** with SAP are prone to exhibit gastrointestinal ***,gastrointestinal dysfunction further aggravates the systemic inflammatory response and metabolic abnormalities,resulting in a more critical condition of *** dysfunction is considered to be the“trigger”of multiple organ dysfunction syndrome[1].Thus,it is important to maintain gastrointestinal homeostasis in the treatment of SAP.

关键词： gastrointestinal pancreatitis acute

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Relation between human existence and environment viewing from the distribution of prehistoric archaeological sites in the Three Gorges reservoir region of the Yangtze River,China

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Chinese Science Bulletin 2008年第S1期53卷 129-139页

作者： ZHAO DongSheng shui tao Department of History Nanjing UniversityNanjing 210093China

Based on archaeological research findings in the Three Gorges region as well as the distribution of prehistoric sites in this area,the following conclusion can be derived:the unique physical and geographical conditions and variations in the Three Gorges region make local people of different ages seek their survival and development in the favorable environment along the *** evolution has direct impact on the selection of location for *** increase of sites quantity reflects the favorable natural environment,but the decrease just reflects the consequence of such natural disasters as flood.

关键词： the Three Gorges of the Yangtze River prehistoric archaeology site distribution environment change human existence

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Diets, eco-environments and seasonal variations recorded in the oxygen and carbon isotopic compositions of mammal tooth enamel from the Shunshanji site,Sihong County,Jiangsu Province,China

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Chinese Science Bulletin 2013年第30期58卷 3788-3795页

作者： TIAN XiaoSi ZHU Cheng shui tao HUANG YunPing The Department of History of Nanjing University Chizhou College School of Geographic and Oceanographic Sciences of Nanjing University Faculty of Archaeology and Museology Peking University

The carbon and oxygen isotopic compositions of the tooth enamel of mammals,including deer,wild pigs,buffaloes and domesticated pigs from the Shunshanji site,Sihong County,Jiangsu Province,China,were analyzed to reconstruct the mammals’ecoenvironments and diets,and to evaluate seasonal variations in the study *** isotopic compositions of buck samples revealed that the deer ate completely C3 plants and the environments they inhabited were relatively open and that wild pigs ate primarily C3 *** isotopic compositions indicated that the body sources of these two mammals were different,*** deer and pigs lived in different niches within a relatively similar *** domesticated pigs were isotopically more positive than the ancient wild pigs in carbon 13C values,suggesting the former ingested more C3 plants relative to the *** the 18O data showed modern domesticated and ancient pigs had similar oxygen isotope compositions,their water sources were *** carbon and oxygen isotopic patterns of premolar microsamples of ancient and modern buffaloes indicated that the plants ingested by the ancient buffalo varied with seasonal shifts,but plants ingested by the modern buffalo were relatively *** eco-environment of the modern buffalo was more open,warmer and drier than eco-environment of the ancient buffalo,which may be the result of the deforestation and other human *** and modern seasonal changes were clearly recorded in the isotopic patterns and the seasonal variation amplitudes of the ancient and modern eco-environments were similar.

关键词：碳同位素组成氧同位素组成生态环境哺乳动物季节变化泗洪县江苏省饮食

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A proposal for detecting weak electromagnetic waves around 2.6μm wavelength with Sr optical clock

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Chinese Physics B 2024年第4期33卷 452-457页

作者：韩弱水王伟汪涛 Department of Physics and Chongqing Key Laboratory for Strongly Coupled PhysicsChongqing UniversityChongqing 401331China Center of Modern Physics Institute for Smart City of Chongqing University in LiyangLiyang 213300China State Key Laboratory of Quantum Optics and Quantum Optics Devices Shanxi UniversityTaiyuan 030006China

Infrared signal detection is widely used in many *** to the detection principle,however,the accuracy and range of detection are *** to the ultra stability of the^(87)Sr optical lattice clock,external infrared electromagnetic wave disturbances can be responded *** the ac Stark shift of the clock transition,we propose a new method to detect infrared *** to our calculations,the theoretical detection accuracy in the vicinity of its resonance band of 2.6μm can reach the order of 10-14W,while the minimum detectable signal of common detectors is on the order of 10^(-10)W.

关键词： infrared signal detection ^(87)Sr optical lattice clock ac Stark shift ultra stability

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Optimal Cooperation Enhancement on Spatial Networks

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Chinese Physics Letters 2014年第11期31卷 1-4页

作者： tao shui-Yuan Cui Ming-Zhu Dai Qiong-Lin Yang Jun-Zhong Beijing Univ Posts & Telecommun Sch Sci Beijing 100876 Peoples R China

We investigate the evolutionary Prisoner＇s dilemma game on the simplest spatial networks constructed as geometrical graphs. The optimal cooperation enhancement against the topology randomness is found. It is proposed that the optimal behavior of the cooperation results from the competition between individuals with high degrees and with low degrees： the former assists the formation of cooperator clusters and the latter tends to prevent the formation of such dusters.

关键词： EVOLUTIONARY PRISONERS-DILEMMA DYNAMICS GAMES

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Numerical simulation on a film-cooled rotating model with 30° injection holes

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航空动力学报 2010年第7期25卷 1443-1453页

作者： YANG Bin XU Guo-qiang tao Zhi DING shui-ting WU Hong-wei National Key Laboratory of Science and Technology on Aero-Engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

The flow and heat transfer characteristics were numerically investigated on a film cooling model under different rotating operating *** computational model was originated from the mid-span section of a typical turbine rotor with two rows of 14 staggered injection holes angled 30° both on the suction surface and pressure surface,and the flow through the coolant plenum and all the hole-pipes were resolved as a part of the computational domain by specifying the coolant mass flux in the *** computations primarily focus on under-standing the rotational effect on film cooling performance in mechanism research *** the present study,the Reynolds number(Re) based on mainstream velocity and injection hole diameter varied from 1835.5 to 5507.4,and the averaged blowing ratio(M) ranges of 0.5 to *** show that the coolant will move on to the high-radius locations near the suction and pressure surfaces due to the strong centrifugal effect,which leads to the decrease in adiabatic effectiveness *** discharge coefficients(Cd),on the pressure surface,are much higher than that on the suction surface under a given operating *** addition,the critical values of angular speed which represent the equilibrium of centrifugal force and Coriolis force near the pressure surface are also presented.

关键词： film cooling rotating adiabatic effectiveness heat transfer discharge coefficient

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A standing wave tube method for measuring acoustic and vibration characteristics of underwater acoustic materials

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Chinese Journal of Acoustics 2024年第3期43卷 348-362页

作者： LI shui YI Yan MO Xiping LIU Yongping HE tao TONG Haoyang Hangzhou Applied Acoustics Research Institute Hangzhou311400 Institute of Acoustics Chinese Academy of SciencesBeijing100190

A measurement method based on standing wave tube is proposed to get the acoustic and vibration characteristic parameters of underwater acoustic materials under hydrostatic pressure.A low-frequency emission transducer with pneumatic compensation is designed as the sound source for standing wave *** a water column,the planar piston vibration of the transducer is coupled to the sample under the water *** accelerometer is installed on the backing of the tested sample to measure the vibration velocity of the sample ***,a pair of hydrophones embedded in the tube wall is used to measure the sound pressure of the water *** on the measured data,the vibration velocity and sound pressure of the sample surface of incidence are *** vibration velocity transfer coefficient(decoupling coefficient)between the front and back surfaces of the sample,the input impedance,and the sound pressure reflection coefficient of the sample are then calculated.A low-frequency standing wave tube test system is constructed with a tube size of 300 mm inner diameter,600 mm outer diameter,and 3 m in height,with a frequency range of 100 Hz to 1000 *** experimental studies are conducted using water layer samples and multi-layer perforated rubber *** results show good agreement with the simulation data,thus validating the effectiveness of the measurement method.

关键词： surface method wave

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