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Implementation Measures for Fire Work Safety in gas Area of Metallurgical Enterprises

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Frontiers of Metallurgical Industry

Frontiers of Metallurgical Industry 2024年第1期2卷 37-39页

作者： Meiting Niu Kaiu Zhan Jiuquan Iron and Steel Group Energy Center

It is an important task to control the dangerous operation of gas fire and reduce the occurrence of gas fire and explosion accidents in ensuring gas operation safety in metallurgical *** with the require-ments of current laws,standards and practical experience,the key points in fire safety management and control are analyzed to solve the gas fire safety problems.

关键词： gas fire operation safety countermeasures

基于gas-CE-LGBM的“一带一路”指数收益率预测研究

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统计学与应用 2024年第4期13卷 1431-1441页

作者：徐泽晖浙江财经大学数据科学学院浙江杭州

研究“一带一路”指数收益率有助于投资者和政策制定者更好地理解和规划“一带一路”倡议相关的金融市场趋势,以支持有效的投资决策和制定经济政策,但由于其复杂性和非线性特征,传统的预测方法可能无法充分捕捉其动态变化。为了解决这... 详细信息

研究“一带一路”指数收益率有助于投资者和政策制定者更好地理解和规划“一带一路”倡议相关的金融市场趋势,以支持有效的投资决策和制定经济政策,但由于其复杂性和非线性特征,传统的预测方法可能无法充分捕捉其动态变化。为了解决这一问题,本文提出了一种结合广义自回归得分(Generalized Autoregressive Score, gas)模型、Copula熵(Copula Entropy, CE)特征选择和监督学习集成模型——轻量梯度提升机(Light Gradient Boosting Machine, LightGBM)模型的综合预测框架(Generalized Autoregressive Score-Copula Entropy-Light Gradient Boosting Machine, gas-CE-LGBM)。首先,构建“一带一路”指数收益率的gas波动率模型并估计参数;其次,计算“一带一路”指数及其成分股相应的Copula熵,并通过阈值进行筛选;最后,将所得成分股信息与gas模型参数构成数据集输入LightGBM模型中建模预测。实验结果表明,gas-CE-LGBM模型相较多层感知器神经网络(Multilayer Perceptron, MLP)、LightGBM、GARCH-LGBM (Generalized Autoregressive Conditional Heteroskedasticity-Light Gradient Boosting Machine)和gas-LGBM (Generalized Autoregressive Score-Light Gradient Boosting Machine)模型在RMSE、MAE、MAPE和R2四个评估指标上表现最佳,RMSE、MAE和MAPE分别平均降低了19.09%、19.81%、62.48%,R2平均提高了12.05%。这表明该模型在“一带一路”指数的预测方面展现了良好的性能和潜力,能更好地捕捉到“一带一路”指数收益率的动态变化。Studying the returns of the “Belt and Road” index contributes to a better understanding and planning for investors and policymakers regarding the financial market trends associated with the “Belt and Road” Initiative. This understanding supports effective investment decisions and economic policy formulation. However, due to its complexity and non-linear characteristics, traditional forecasting methods might not adequately capture its dynamic changes. To address this issue, this paper proposes a comprehensive predictive framework, the Generalized Autoregressive Score-Copula Entropy-Light Gradient Boosting Machine (gas-CE-LGBM) model, which combines the Generalized Autoregressive Score (gas) model, Copula Entropy (CE) feature selection and supervised learning ensemble model—Light Gradient Boosting Machine (LightGBM). First, build the volatility gas model of the return rate of the “Belt and Road” index and estimate the parameters. Secondly, calculate the corresponding Copula entropy of the “Belt and Road” index and its constituent stocks and filter through the threshold. Finally, input the data set of constituent stoc

关键词： gas LightGBM Copula熵 “一带一路”

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低维gas高响应度纸基光电探测器

物理实验 2024年第4期44卷 7-11,24页

作者：辛巍仲玮恒王晓颖闫楚欣刘为振东北师范大学物理学院吉林长春130024 东北师范大学物理学师范专业国家级实验教学示范中心(东北师范大学) 吉林长春130024

随着石墨烯的发现,二维材料因其与众不同的理化性质,而在科研领域的关注度与日俱增.以石墨烯为起点的二维材料(例如MoS_(2),WS_(2),gas等)因在器件中具有较好的光电性质和较高的迁移率,而在生产和生活中具有良好的应用前景.本文简要探... 详细信息

随着石墨烯的发现,二维材料因其与众不同的理化性质,而在科研领域的关注度与日俱增.以石墨烯为起点的二维材料(例如MoS_(2),WS_(2),gas等)因在器件中具有较好的光电性质和较高的迁移率,而在生产和生活中具有良好的应用前景.本文简要探讨了光电导效应的原理,采用铅笔勾勒的方法绘制出了石墨电极,并采用体材料液相超声后分散液滴涂的方法,制备了宏观尺度的gas纸基光电探测器,该探测器具有可见光范围的光电响应,且具有较好的机械重复性.本文介绍的纸基光电探测器的制备方法对于高校基础物理和半导体物理课程的教学具有实际意义,有利于学生更好地理解光电导效应的原理.此外,纸基光电探测器不仅降低了制备成本,而且还有助于提高高校学生的科研实践能力.

关键词： gas 光电导效应纸基光电探测器

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跨音转子尖区流动的gas模拟

跨音转子尖区流动的GAS模拟

基于gas和HyperBeam的某前纵梁截面关键力学性能分析

北京力学会第30届学术年会

作者：郭建民唐雨萌柳阳威

本文采用网格自适应模拟(Grid-Adaptive Simulation, gas)方法对Darmstadt跨音转子展开了数值模拟研究,验证了gas方法具有高精度、低计算耗费的特点;研究了大流量工况和近失速工况下转子尖区流动结构,并对激波与泄漏涡相互作用进行了分... 详细信息

本文采用网格自适应模拟(Grid-Adaptive Simulation, gas)方法对Darmstadt跨音转子展开了数值模拟研究,验证了gas方法具有高精度、低计算耗费的特点;研究了大流量工况和近失速工况下转子尖区流动结构,并对激波与泄漏涡相互作用进行了分析。结果表明:叶轮机泄漏涡与激波作用机制存在两个显著特征:泄漏涡经过激波后迅速膨胀,并在下游形成回流区堵塞流道;激波和泄漏涡作用后会发生分离。

关键词：混合RANS-LES方法 gas 激波-泄漏涡作用叶尖泄漏流

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汽车零部件 2024年第4期 58-62页

作者：武敬伟郭涛苏宇锋柳州铁道职业技术学院广西柳州545616

车身截面形状决定了薄壁梁的力学特性,对车身的性能起着至关重要的作用。通过对某前纵梁截面分别进行基于gas和HyperBeam软件模块的截面性能分析,对比两者关键性能参数结果差异,并分析了差异原因,最后对比有限元模型和gas压馈力计算结... 详细信息

车身截面形状决定了薄壁梁的力学特性,对车身的性能起着至关重要的作用。通过对某前纵梁截面分别进行基于gas和HyperBeam软件模块的截面性能分析,对比两者关键性能参数结果差异,并分析了差异原因,最后对比有限元模型和gas压馈力计算结果。综合以上对比结果得出,基于gas计算的截面关键特性结果具有较好的工程指导意义。

关键词：截面性能 gas HyperBeam 压馈力

Comparison of feasibility,microstructure and performance of hybrid laser arc,activated flux tungsten inert gas and friction stir welding for thick plate of innovative ultra-pure ferritic stainless steel

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Journal of Iron and Steel Research(International) 2022年第4期29卷 665-676页

作者： Jian Han Lian-meng Liu Xin-ya Chen Min-fang Chen Lei Cui Yang-chuan Cai Yin-bao Tian School of Materials Science and Engineering Tianjin University of TechnologyTianjin 300384China School of Materials Science and Engineering Tianjin UniversityTianjin 300072China

An innovative grade of ferritic stainless steel,ultra-pure 18Cr–2Mo thick plate,was designed and produced for special industrial *** order to maintain its mechanical properties after joining,three advanced joining methods,hybrid laser arc welding,activated flux tungsten inert gas welding and friction stir welding,were selected and conducted to connect the thick *** feasibility of three joining methods,the microstructure and mechanical properties were compared,and the results have demonstrated that the sound joint was successfully produced using the selected parameters through friction stir *** obtained hardness and impact toughness of the weld zone were *** terms of activated flux tungsten inert gas welding,the crack will be created due to microstructural *** as for hybrid laser arc welding,the weld zone is narrow,and the addition of wire during welding for the top weld metal area leads to higher formation ratio of low-angle grain boundaries,which is beneficial to performance of the ***,there is still a weak area in the fusion line of the welded *** result has illustrated that the welding of innovative ultra-pure ferritic stainless steel thick plate by friction stir welding is feasible.

关键词： Ultra-pure ferritic stainless steel Hybrid welding Activated flux tungsten inert gas Friction stir welding Microstructural evolution Mechanical property

Geological conditions of natural gas accumulation and new exploration areas in the Mesoproterozoic to Lower Paleozoic of Ordos Basin, NW China

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Petroleum Exploration and Development 2019年第5期46卷 866-882页

作者： DU Jinhu LI Xiangbo BAO Hongping XU Wanglin WANG Yating HUANG Junping WANG Hongbo WANYAN Rong WANG Jing PetroChina Exploration&Production Company Beijing 100007China Northwest Branch Research Institute of Petroleum Exploration&DevelopmentPetroChinaLanzhou 730020China Research Institute of Petroleum Exploration&Development PetroChina Changqing Oilfield CompanyXi’an 710018China Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China

Based on field outcrop investigation,interpretation and analysis of drilling and seismic data,and consulting on a large number of previous research results,the characteristics of ancient marine hydrocarbon source rocks,favorable reservoir facies belts,hydrocarbon migration direction and reservoir-forming law in the Ordos Basin have been studied from the viewpoints of North China Craton breakup and Qilian-Qinling oceanic basin opening and *** main results are obtained:(1)Controlled by deep-water shelf-rift,there are three suites of source rocks in the Ordos Basin and its periphery:Mesoproterozoic,Lower Cambrian and Middle-Upper Ordovician.(2)Controlled by littoral environment,paleo-uplift and platform margin,four types of reservoirs are developed in the area:Mesoproterozoic-Lower Cambrian littoral shallow sea quartz sandstone,Middle-Upper Cambrian–Ordovician weathering crust and dolomitized reservoir,and Ordovician L-shape platform margin reef and beach bodies.(3)Reservoir-forming assemblages vary greatly in the study area,with"upper generation and lower storage"as the main pattern in the platform,followed by"self-generation and self-storage".There are both"upper generation and lower storage"and"self-generation and self-storage"in the platform margin *** addition,in the case of communication between deep-large faults and the Changchengian system paleo-rift trough,there may also exist a"lower generation and upper reservoir"combination between the platform and the margin.(4)There are four new exploration fields including Qingyang paleo-uplift pre-Carboniferous weathering crust,L-shape platform margin zone in southwestern margin of the basin,Ordovician subsalt assemblage in central and eastern parts of the basin,and Mesoproterozoic–*** them,pre-Carboniferous weathering crust and L-shape platform margin facies zone are more realistic replacement areas,and Ordovician subsalt assemblage and the Proterozoic-Cambrian have certain potential and are wor

关键词： natural gas exploration area hydrocarbon accumulation geological conditions Mesoproterozoic Neoproterozoic Lower Paleozoic Ordos Basin

Re-recognition of “unconventional” in unconventional oil and gas

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Petroleum Exploration and Development 2019年第5期46卷 847-855页

作者： JIAO Fangzheng China National Petroleum Corporation Beijing 100007China

Taking the Wufeng–Longmaxi shale gas in the Sichuan Basin as a typical example,based on the new progress in exploration and development,this study re-examines the"unconventional"of unconventional oil and gas from two aspects:oil and gas formation and accumulation mechanisms,and main features of oil and gas *** oil and gas of continuous accumulation and distribution from integrated source and reservoir is unconventional oil and gas,and the study focusing on shale oil and gas in comparison with conventional oil and gas has made progress in five aspects:(1)Unconventional oil and gas have source-reservoir-in-one and in-situ accumulation;according to the theory of continuous oil and gas accumulation,the accumulation power of oil and gas is overpressure and diffusion;for conventional oil and gas,the source and reservoir are different formations,the trapping accumulation is its theoretical foundation,and the accumulation power is characterized by buoyancy and capillary force.(2)The unconventional oil and gas reservoirs are mainly formed in the low-energy oxygen-anaerobic environment,dominantly semi-deep to deep shelf facies and the semi-deep to deep lake facies,simple in lithology,rich in organic matter and clay minerals;conventional oil and gas mainly occur in coarse-grained sedimentary rocks formed in high-energy waters with complex lithology.(3)The unconventional oil and gas reservoirs have mainly nano-scale pores,of which organic matter pores take a considerable proportion;conventional oil and gas reservoirs mainly have micron-millimeter pores and no organic matter pores.(4)Unconventional shale oil and gas reservoirs have oil and gas in uniform distribution,high oil and gas saturation,low or no water content,and no obvious oil and gas water boundary;conventional oil and gas reservoirs have oil and gas of complex properties,moderate oil and gas saturation,slightly higher water content,and obvious oil,gas and water boundaries.(5)Organic-rich shale is the main targ

关键词： unconventional oil and gas theoretical connotation shale oil and gas hydrocarbon accumulation dynamics organic matter fine grain deposition Wufeng–Longmaxi Formations Sichuan Basin

Major progress in the natural gas exploration and development in the past seven decades in China

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Petroleum Exploration and Development 2019年第6期46卷 1100-1110页

作者： DAI Jinxing QIN Shengfei HU Guoyi NI Yunyan GAN Lideng HUANG Shipeng HONG Feng PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China

China has made significant progress in the exploration and development of natural gas in the past 70 years,from the gas-poor country to the world’s sixth largest gas production *** 1949,the annual gas output in China was 1117×104 m3,the proved gas reserves were 3.85×108 m3,and the average annual gas consumption and available reserves of per person were 0.0206 m3 and 0.7107 m3,*** 2018,the average domestic annual gas production per person was 114.8576 m3 and the reserves were 12011.08 m3,and the average domestic annual gas production and reserves per person in the past 70 years increased by 5575 times and 16900 times,*** exploration and development of large gas fields is the main way to rapidly develop the natural gas industry.72 large gas fields have been discovered in China so far,mainly distributed in three basins,Sichuan(25),Ordos(13)and Tarim(10).In 2018,the total gas production of the large gas fields in these three basins was 1039.26×108 m3,accounting for 65%of the total gas production in *** the end of 2018,the cumulative proved gas reserves of the 72 large gas fields had amounted to 124504×108 m3,accounting for 75%of the total national gas reserves(16.7×1012 m3).New theories of natural gas have promoted the development of China’s natural gas industry *** 1979,the new theory of coal-derived gas has boosted the discovery of gas fields mainly from coal-measure source rocks in *** 2018,the gas production of large coal-derived gas fields in China accounted for 50.93%and 75.47%of the total national gas production and total gas production of large gas fields,*** by shale gas theories,shale gas fields such as Fuling,Changning,Weiyuan and Weirong have been *** 2018,the total proved geological reserves of shale gas were 10455.67×108 m3,and the annual gas production was 108.8×108 m3,demonstrating a good prospect of shale gas in China.

关键词： China natural gas coal-derived gas shale gas gas production gas reserves exploration and development progress