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基于24Model-D-ISM的地铁站火灾疏散影响因素研究
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作者 孙世梅 张家严 《中国安全科学学报》 CAS CSCD 北大核心 2024年第4期153-159,共7页
为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾... 为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾人员疏散影响因素指标体系;采用算子客观赋权法(C-OWA)改进决策试验与评价实验法(DEMATEL),确定地铁站火灾人员疏散的重要影响因素;在此基础上,采用解释结构模型(ISM)分析各个因素间的层次结构及相互作用路径,构建地铁站火灾人员疏散影响因素的多级递阶结构模型。研究结果表明:疏散引导、恐慌从众行为、人员拥挤为地铁站火灾人员疏散的关键影响因素;地铁站火灾人员疏散受表层因素、中间层因素、深层因素共同作用的影响,其中,疏散教育与培训、设施维护与检查、疏散预案等因素是根源影响因素,重视根源影响因素的改善有利于从本质上预防和控制事故的发生。 展开更多
关键词 “2-4”模型(24model) 决策试验与评价实验法(DEMATEL) 解释结构模型(ISM) 地铁站 火灾疏散 影响因素
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An Investigation into Green Total Factor Productivity in China's Carbon-Intensive Sectors and Its Influencing Factors
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作者 Pu Lijuan Zhu Shuaihui 《Contemporary Social Sciences》 2024年第3期64-76,共13页
This paper uses an SBM-GML index model to assess Green Total Factor Productivity(GTFP)in China's carbon-intensive sectors and conducts an empirical investigation into which factors influence GTFP in these sectors.... This paper uses an SBM-GML index model to assess Green Total Factor Productivity(GTFP)in China's carbon-intensive sectors and conducts an empirical investigation into which factors influence GTFP in these sectors.The GTFP in the carbon-intensive sectors experienced a decline between 2006 and 2011,followed by an upward trend beginning in 2012.Technological progress was the primary driver of GTFP growth,while business size was also a notable contributor.Irrational energy structures negatively influenced the high-quality development of the carbon-intensive sectors,and environmental regulation and foreign direct investment(FDI)have not yet significantly impacted GTFP.Based on these findings,this paper suggests that the carbon-intensive sectors should expedite their green transitions by focusing on system improvement,technological innovations,energy revolutions,and high-level opening up. 展开更多
关键词 carbon-intensive sectors GTFP SBM-GML index model
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A Two-Sector Economic Growth Model with Labor Force 被引量:1
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作者 Cai Dong\|han, Zhou Ming\|chun School of Mathematics and Statistics, Wuhan University , Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03A期769-774,共6页
In this paper, a two\|sector growth model is given. The labor force transfer process from agricultural sector to industrial sector is exogenous determined. By introducing the labor force transferring function, a two\|... In this paper, a two\|sector growth model is given. The labor force transfer process from agricultural sector to industrial sector is exogenous determined. By introducing the labor force transferring function, a two\|dimension nonautonomous differential equation is obtained. The results of the model manifest that the labor force transfer delays industrial sector growth and accelerates the agricultural sector growth. It is proved that the solution of the model is asymptotic stable. By the numerical analysis, the economic growth and labor force transfer is presented under the specific parameters. 展开更多
关键词 two\|sector economic growth model labor force transfer asymptotic stability
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24Model与LCM原因因素定义对比研究
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作者 袁晨辉 傅贵 +1 位作者 吴治蓉 赵金坤 《中国安全科学学报》 CAS CSCD 北大核心 2024年第1期27-34,共8页
为探究损失致因模型(LCM)原因因素定义与事故致因“2-4”模型(24Model)存在的异同和优缺点,梳理2个模型各层面原因和结果的定义,对比定义内容及其对事故原因分析等安全实务的指导作用,并以一起瓦斯爆炸事故为例加以实证分析,获得二者分... 为探究损失致因模型(LCM)原因因素定义与事故致因“2-4”模型(24Model)存在的异同和优缺点,梳理2个模型各层面原因和结果的定义,对比定义内容及其对事故原因分析等安全实务的指导作用,并以一起瓦斯爆炸事故为例加以实证分析,获得二者分析结果之间的差异。研究结果表明:LCM是首个将管理因素纳入事故致因分析的一维事件序列模型,可明确各层面原因因素的定义和因素间的逻辑关系,但部分定义存在交叉重复的问题,并没有揭示安全工作指导思想等深层次事故致因因素;24Model作为系统性事故致因模型,对各类因素的定义均以组织为主体,描述事件、事故、安全的概念内涵,划分个体安全动作、安全能力和组织安全管理体系的类别并给出含义解析,探究组织安全文化层面的问题并以32个元素体现;2个模型的事故原因分析方法均建立在对各层级原因因素定义的基础上,并适用于模型理论体系本身。 展开更多
关键词 “2-4”模型(24model) 损失致因模型(LCM) 事故致因模型 原因因素定义 对比研究
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Fixed-Bed Column Adsorption Modeling of MnO4- Ions from Acidic Aqueous Solutions on Activated Carbons Prepared with the Biomass
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作者 Charly Mve Mfoumou Francis Ngoye +3 位作者 Pradel Tonda-Mikiela Mbouiti Lionel Berthy Bouassa Mougnala Spenseur Guy Raymond Feuya Tchouya 《Open Journal of Inorganic Chemistry》 CAS 2023年第2期25-42,共18页
Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-<... Activated carbons calcined at 400˚C and 600˚C (AC-400 and AC-600), prepared using palm nuts, collected in the town of Franceville in Gabon, were used to study the dynamic adsorption of MnO<sub>4</sub>-</sup> ions in acidic media on fixed bed column and on the kinetic modeling of experimental data of breakthrough curves of  MnO<sub>4</sub>-</sup> ions obtained. Results on the adsorption of MnO<sub>4</sub>-</sup>  ions in fixed-bed dynamics obtained on AC-400 and AC-600 adsorbents beds indicated that the AC-400 bed appears to be the most efficient in removing MnO<sub>4</sub>-</sup>  ions in acidic media. Indeed, the adsorbed amounts, the adsorbed capacities at saturation and the elimination percentage of MnO<sub>4</sub>-</sup>  ions obtained with AC-400 (31.24 mg;52.06 mg·g<sup>-1</sup> and 41.65% respectively) were higher compared to those obtained with AC-600 (9.87 mg;16.45 mg·g<sup>-1</sup> and 17.79% respectively). The breakthrough curves kinetic modeling revealed that the Thomas model and the pseudo-first-order kinetic model were the most suitable models to describe the adsorption of MnO<sub>4</sub>-</sup>  ions on adsorbents studied in our experimental conditions. The results of the intraparticle diffusion model showed that intraparticle diffusion was involved in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions on investigated adsorbents and was not the limiting step and the only process controlling MnO<sub>4</sub>-</sup>  ions adsorption. In contrast to AC-400, the intraparticle diffusion on AC-600 bed plays an important role in the adsorption mechanism of MnO<sub>4</sub>-</sup>  ions. 展开更多
关键词 Acidic Media MnO4 style=margin-left:-6px >- BIOMASS Activated Carbon Dynamic Adsorption Kinetics models
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24 Model在道路运输事故成因中的应用
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作者 刘晓露 梁志星 +2 位作者 吴君安 严玉琼 张苏 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第2期185-192,共8页
为预防道路运输事故,基于事故致因“2-4”(24 Model)模型,对2015—2021年发生的215起道路运输事故的行为原因进行研究。从个人层面和组织层面分析导致事故发生的直接原因、间接原因、根本原因及其根源原因。结果表明:发生频次最多的不... 为预防道路运输事故,基于事故致因“2-4”(24 Model)模型,对2015—2021年发生的215起道路运输事故的行为原因进行研究。从个人层面和组织层面分析导致事故发生的直接原因、间接原因、根本原因及其根源原因。结果表明:发生频次最多的不安全动作是驾驶员超速行驶(占10.67%);22.33%的道路运输事故存在管理者违章安排无资质员工上岗作业;管理者和领导者对57.67%的道路运输事故的发生有重要影响;由人为因素产生的不安全物态占比达71.53%;驾驶员、车辆安全生产管理制度欠缺或执行不到位在根本原因中尤为突出(占20.92%)。基于此,提出道路运输事故预防对策并构建出道路运输系统各因素关系图。 展开更多
关键词 汽车主动安全 道路运输事故 事故致因 “2-4”模型(24 model) 对策
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中国碳市场、能源市场和高排放行业间的溢出效应研究——基于TVP-VAR-DY模型
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作者 任峥宇 陈省宏 +2 位作者 唐健 章天晏 郁洋 《能源环境保护》 2024年第3期162-172,共11页
在以低碳发展应对全国气候变化的共识下,继电力市场后,将其他高排放行业纳入全国碳市场势在必行。探究2021年至2023年期间全国碳市场、能源市场和高排放行业市场间的风险溢出效应。通过采用TVP-VAR-DY模型,使动态溢出效应的测度更加平... 在以低碳发展应对全国气候变化的共识下,继电力市场后,将其他高排放行业纳入全国碳市场势在必行。探究2021年至2023年期间全国碳市场、能源市场和高排放行业市场间的风险溢出效应。通过采用TVP-VAR-DY模型,使动态溢出效应的测度更加平滑。研究发现,全国碳市场、能源市场与高排放行业市场存在时变的双向不对称溢出效应,特别是在极端风险事件下,市场之间的波动溢出效应显著增强。电力等高排放行业市场主要受碳市场波动的影响,而新能源行业风险主要影响原油期货市场。重大社会经济事件可导致能源市场在短期内成为风险传递的主导因素,但随着时间推移,高排放行业会转为风险输出者。最后,提出了关于中国碳市场建设、能源市场风险防范和高排放行业能源结构优化等方面的建议。 展开更多
关键词 碳市场 高排放行业 能源市场 TVP-VAR-DY模型 风险溢出效应
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Overreliance on Net Export and Investment Impedes China's Structural Transformation: Estimation and Analysis Based on a Multi-Sector Growth Model
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作者 渠慎宁 李鹏飞 吕铁 《China Economist》 2019年第3期44-65,共22页
Since reform and opening-up in 1978, changes in China's industrial structure have generally followed the pattern of "Kuznets facts" but still exhibits some unique characteristics, which led us to raise t... Since reform and opening-up in 1978, changes in China's industrial structure have generally followed the pattern of "Kuznets facts" but still exhibits some unique characteristics, which led us to raise the following three questions regarding China's structural transformation:(1) Why did the share of China's agricultural and manufacturing employment reduce/increase intermittently rather than continuously?(2) Why did the share of China's agricultural employment increase during certain periods? When the share of manufacturing employment reduced, why did the workforce reversely flow into agriculture rather than move to the service sector?(3) Why did growth in the share of China's service sector employment decelerate before reaching its peak? Why did the share of employment in the industrial sector suddenly increase after an abrupt decline? This paper creates a multisector economic growth model that contains non-homothetic preferences and differentiated productivity, and incorporates the "two drivers" therein for a demand-side estimation and analysis. The result shows that China's economic growth model driven by net export and investment is a critical factor for explaining the three questions regarding its structural transformation. This paper believes that only by implementing supply-side structural reforms, reducing the dependence on net export and investment, and achieving sustainable endogenous economic growth will China be able to expedite its industrial restructuring. 展开更多
关键词 STRUCTURAL transformation net EXPORT and INVESTMENT multi-sector economic growth model supply-side STRUCTURAL REFORMS
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A hybrid Lagrangian-Eulerian numerical model for sea-ice dynamics 被引量:3
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作者 JI Shunying LI Hai +2 位作者 SHEN Hung Tao WANG Ruixue YUE Qianjin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第5期12-24,共13页
A hybrid Lagrangian - Eulerian (HLE) method is developed for sea ice dynamics, which combines the high computational efficiency of finite difference method (FDM) with the high numerical accuracy of smoothed partic... A hybrid Lagrangian - Eulerian (HLE) method is developed for sea ice dynamics, which combines the high computational efficiency of finite difference method (FDM) with the high numerical accuracy of smoothed particle hydrodynamics (SPH). In this HLE model, the sea ice cover is represented by a group of Lagrangian ice particles with their own thicknesses and concentrations. These ice variables are interpolated to the Eularian gird nodes using the Gaussian interpolation function. The FDM is used to determine the ice velocities at Eulerian grid nodes, and the velocities of Lagrangian ice particles are interpolated from these grid velocities with the Gaussian function also. The thicknesses and concentrations of ice particles are determined based on their new locations. With the HLE numerical model, the ice ridging process in a rectangular basin is simulated, and the simulated results are validated with the analytical solution. This method is also applied to the simulation of sea ice dynamics in a vortex wind field. At last, this HLE model is applied to the Bohai Sea, and the simulated concentration, thickness and velocity match the satellite images and the field observed data well. 展开更多
关键词 hybrid Lagrangian - Eulerian model sea-ice dynamics numerical model
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Analysis of axial strain in one-dimensional loading by different models 被引量:2
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作者 G.Aryanpour M.Farzaneh 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第5期745-753,共9页
Different phenomenological equations based on plasticity, primary creep (as a viscoplastic mechanism), secondary creep (as another viscoplastic mechanism) and different combinations of these equations are presente... Different phenomenological equations based on plasticity, primary creep (as a viscoplastic mechanism), secondary creep (as another viscoplastic mechanism) and different combinations of these equations are presented and used to describe the material inelastic deformation in uniaxial test. Agreement of the models with experimental results and with the theoretical concepts and physical realities is the criterion of choosing the most appropriate formulation for uniaxial test. A model is thus proposed in which plastic deformation, primary creep and secondary creep contribute to the inelastic deformation. However, it is believed that the hardening parameter is composed of plastic and primary creep parts. Accordingly, the axial plastic strain in a uniaxial test may no longer be considered as the hardening parameter. Therefore, a proportionality concept is proposed to calculate the plastic contribution of deformation. 展开更多
关键词 modelling Uniaxial test Plastic - Creep Strain hardening - Proportionality
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Analytical models for the penetration of semi-infinite targets by rigid,deformable and erosive long rods 被引量:14
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作者 He-Ming Wen Bin Lan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期573-583,共11页
A theoretical study is presented herein on the pen- etration of a semi-infinite target by a spherical-headed long rod for Yp 〉 S, where Yp is the penetrator strength and S is the static target resistance. For Yp 〉 S... A theoretical study is presented herein on the pen- etration of a semi-infinite target by a spherical-headed long rod for Yp 〉 S, where Yp is the penetrator strength and S is the static target resistance. For Yp 〉 S, depending upon initial impact velocity, there exist three types of penetration, namely, penetration by a rigid long rod, penetration by a deforming non-erosive long rod and penetration by an erosive long rod. If the impact velocity of the penetrator is higher than the hydrodynamic velocity (VH), it will penetrate the target in an erosive mode; if the impact velocity lies between the hydrodynamic velocity (VH) and the rigid body velocity (VR), it will penetrate the target in a deformable mode; if the impact velocity is less than the rigid body velocity (VR), it will penetrate the target in a rigid mode. The critical conditions for the transition among these three penetration modes are proposed. It is demonstrated that the present model predictions correlate well with the experimental observations in terms of depth of penetration (DOP) and the critical transition conditions. 展开更多
关键词 Long rod Semi-infinite target - Penetration Alekseevskii-Tate model Rigid body velocity - Hydrodynamic velocity
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Roll System and Stock's Multi-parameter Coupling Dynamic Modeling Based on the Shape Control of Steel Strip 被引量:3
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作者 Yang ZHANG Yan PENG +1 位作者 Jianliang SUN Yong ZANG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期614-624,共11页
The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformatio... The existence of rolling deformation area in the rolling mill system is the main characteristic which dis- tinguishes the other machinery. In order to analyze the dynamic property of roll system's flexural deformation, it is necessary to consider the transverse periodic movement of stock in the rolling deformation area which is caused by the flexural deformation movement of roll system simul- taneously. Therefore, the displacement field of roll system and flow of metal in the deformation area is described by kinematic analysis in the dynamic system. Through intro- ducing the lateral displacement function of metal in the deformation area, the dynamic variation of per unit width rolling force can be determined at the same time. Then the coupling law caused by the co-effect of rigid movement and flexural deformation of the system structural elements is determined. Furthermore, a multi-parameter coupling dynamic model of the roll system and stock is established by the principle of virtual work. More explicitly, the cou- pled motion modal analysis was made for the roll system. Meanwhile, the analytical solutions for the flexural defor- mation movement's mode shape functions of rolls are discussed. In addition, the dynamic characteristic of the lateral flow of metal in the rolling deformation area has been analyzed at the same time. The establishment ofdynamic lateral displacement function of metal in the deformation area makes the foundation for analyzing the coupling law between roll system and rolling deformation area, and provides a theoretical basis for the realization of the dynamic shape control of steel strip. 展开更多
关键词 Roll system Rolling deformation area Coupling dynamic model Mode shape function - Lateraldisplacement function
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Modelling of Quasi 3-D Groundwater Flow and Studying of Equivalent Drainage Boundary in Beihai Peninsula,Guangxi 被引量:2
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作者 Chen Chongxi Lin Min Li GuominChina University of Geosciences , Wuhan 430074Jiang Jianmin Ye Shanshi Wu NaidongGeology Bureau of Guangxi Autonomous Region , Naming 530023 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期109-119,共11页
This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through th... This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through the aquitard . It is applied to evaluate the maximum rate of groundwater resources exploited from the coastal aquifer without seawater intrusion . The main task in this model is to determine the drainage boundary of the aquifer extending under the sea . The information of the boundary can be obtained from the fluctuations of the groundwater level caused by sea-tide fluctuations . A new idea, Equivalent Drainage Boundary (EDB), is proposed and the corresponding methods , determining the EDB, are developed with tidal fluctuations data observed in boreholes . The quasi 3-D model and the methods determining EDB have been applied to the aquifer system of Beihai peninsula , Guangxi Autonomous Region of China for calculating the available groundwater resources . 展开更多
关键词 quad 3 - D model coastal aquifer Equivalent Drainage Boundary available groundwater resources Beihai peninsula .
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Kinetic Modeling the Formation of Low-mature Gases and Analysis of the Possibility to Be Accumulated 被引量:2
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作者 SHUAI Yanhua WANG Hui ZHANG Shuichang SU Aiguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期537-542,共6页
At present, shallow gases have received much attention due to low cost in exploration and production. Low-mature gases, as one significant origin to shallow gas, turns to be an important research topic. The present un... At present, shallow gases have received much attention due to low cost in exploration and production. Low-mature gases, as one significant origin to shallow gas, turns to be an important research topic. The present understanding of low-mature gases is confined within some geological cases, and few laboratory studies have been reported. Therefore, the potential and characters of low- mature gases are not clear up to now. Here, two premature samples (one coal and the other shale) were pyrolyzed in a gold confined system. The gaseous components including hydrocarbon gases and non-hydrocarbon gases were analyzed. Based on kinetic modeling, the formation of low-mature gases was modeled. The results showed that during low mature stage, about 178 mL/gTOC gas was generated from the shale and 100 mL/gTOC from the coal. Two third to three fourth of the generated gases are non-hydrocarbon gases such as H2S and CO2. The total yields of C1-5 for the two samples are almost the same, 30-40 mL/gTOC, but individual gaseous hydrocarbon is different. The shale has much lower C1 but higher C2-5, whereas the coal has higher C1 but lower C2-5. Hydrocarbon gases formed during low-mature stage are very wet. The stable carbon isotope ratios of methane range from -40‰ to -50‰ (PDB), in good consistence with empiric criterion for low-mature gases summed up by the previous researchers. The generation characters suggest that the low-mature gases could be accumulated to form an economic gas reservoir, but most of them occur only as associated gases. 展开更多
关键词 low-mature gases kinetic modeling carbon isotope ratio of methane potential of C1-5
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Investment in deepwater oil and gas exploration projects:a multi-factor analysis with a real options model 被引量:4
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作者 Xin-Hua Qiu Zhen Wang Qing Xue 《Petroleum Science》 SCIE CAS CSCD 2015年第3期525-533,共9页
Deepwater oil and gas projects embody high risks from geology and engineering aspects, which exert substantial influence on project valuation. But the uncer- tainties may be converted to additional value to the projec... Deepwater oil and gas projects embody high risks from geology and engineering aspects, which exert substantial influence on project valuation. But the uncer- tainties may be converted to additional value to the projects in the case of flexible management. Given the flexibility of project management, this paper extends the classical real options model to a multi-factor model which contains oil price, geology, and engineering uncertainties. It then gives an application example of the new model to evaluate deepwater oil and gas projects with a numerical analytical method. Compared with other methods and models, this multi-factor real options model contains more project information. It reflects the potential value deriving not only from oil price variation but also from geology and engi- neering uncertainties, which provides more accurate and reliable valuation information for decision makers. 展开更多
关键词 Investment decision - Real options Multi-factor model Option pricing - Deepwater oil and gas
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A Numerical Algorithm Based on Quadratic Finite Element for Two-Dimensional Nonlinear Time Fractional Thermal Diffusion Model 被引量:3
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作者 Yanlong Zhang Baoli Yin +2 位作者 Yue Cao Yang Liu Hong Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第3期1081-1098,共18页
In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-d... In this article,a high-order scheme,which is formulated by combining the quadratic finite element method in space with a second-order time discrete scheme,is developed for looking for the numerical solution of a two-dimensional nonlinear time fractional thermal diffusion model.The time Caputo fractional derivative is approximated by using the L2-1formula,the first-order derivative and nonlinear term are discretized by some second-order approximation formulas,and the quadratic finite element is used to approximate the spatial direction.The error accuracy O(h3+t2)is obtained,which is verified by the numerical results. 展开更多
关键词 Quadratic finite element two-dimensional nonlinear time fractional thermal diffusion model L2-1formula.
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Thermodynamic modeling and phase diagram prediction of salt lake brine systemsⅡ.Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems 被引量:6
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作者 Huan Zhou Peng Wu +3 位作者 Wenxuan Li Xingfan Wang Kuo Zhou Qing Hao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期134-149,共16页
It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high conc... It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ))associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constantsΔ_(f)G_(k)°^((298.15))andΔ_(f)H_(k)°^((298.15))of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1)solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2)isothermal phase diagrams for Li_(2)SO_(4)-Na_(2)SO_(4)-H_(2)O,Li_(2)SO_(4)-K_(2)SO_(4)-H_(2)O and Na_(2)SO_(4)-K_(2)SO_(4)-H_(2)O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data. 展开更多
关键词 Aqueous electrolytes Comprehensive thermodynamic model Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) Phase diagram Thermodynamic properties
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Aeroelastic modeling of wind loading on a cable-net supported glass wall 被引量:1
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作者 Zhifu Gu Letian Yang Yan Li Bin Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第3期409-415,共7页
Wind loading study on a cable-net supported glass wall is conducted by means of wind tunnel tests. An equiva- lent aeroelastic model is designed and constructed. Response of displacements of the wall is measured and a... Wind loading study on a cable-net supported glass wall is conducted by means of wind tunnel tests. An equiva- lent aeroelastic model is designed and constructed. Response of displacements of the wall is measured and analyzed. In order to design a glass wall under wind loading, the "wind- vibration factor" is estimated and discussed. In fact, the mech- anism of wind acting on the wall is commonly known not only as positive pressure, but also as negative pressure caused by the flow separation on the corners of the building. Due to the diffidence in the mechanism of wind acting, two typi- cal response cases are classified. The results show that the dynamic response of the structure caused by the negative pressure is stronger than that of the positive pressure case. To determine the aerodynamic wind loading on a flexible part of structure on a building, wind tunnel study may be useful and play an important role. 展开更多
关键词 Wind tunnel study Cable-net supported glasswall - Wind-vibration factor Aeroelastic model
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Lumped parameter analytic modeling and behavioral simulation of a 3-DOF MEMS gyro-accelerometer 被引量:1
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作者 Payal Verma Sandeep K.Arya Ram Gopal 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第6期910-919,共10页
A new analytical model of a 3-degree-of-freedom (3-DOF) gyro-accelerometer system consisting of a 1-DOF drive and 2-DOF sense modes is presented. The model constructs lumped differential equations associated with ea... A new analytical model of a 3-degree-of-freedom (3-DOF) gyro-accelerometer system consisting of a 1-DOF drive and 2-DOF sense modes is presented. The model constructs lumped differential equations associated with each DOFof the system by vector analysis. The coupled differential equations thus established are solved analytically for their responses in both the time and frequency domains. Considering these frequency response equations, novel device design concepts are derived by forcing the sense phase to zero, which leads to a certain relationship between the structural frequencies, thereby causing minimization of the damping effect on the performance of the system. Furthermore, the feasibility of the present gyro-accelerometer structure is studied using a unique discriminatory scheme for the detection of both gyro action and linear acceleration at their events. This scheme combines the formulated settled transient solution of the gyro-accelerometer with the processes of synchronous demodulation and filtration, which leads to the in-phase and quadrature components of the system's output signal. These two components can be utilized in the detection of angular motion and linear acceleration. The obtained analytical results are validated by simulation in a MATLAB/Simulink environment, and it is found that the results are in excellent agreement with each other. 展开更多
关键词 Microelectromechanical systems (MEMS) ·Multimeasurement system. Gyro-accelerometer Gyro-accelerometer model - Transient model
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Effects of natural-cerebrolysin-containing serum on neurotoxicity and synaptogenesis in amyloid-beta 1-40-induced Alzheimer's disease in vitro models 被引量:1
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作者 Yinghong Li Zhengzhi Wu +3 位作者 Andrew C. J. HuangO Ming Li XiaoLi Zhang Jiguo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第2期85-91,共7页
BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, an... BACKGROUND: Neuronal loss, synapse mutilation, and increasing malnourished axons are pathologically related to Alzheimer's disease. Microtubule-associated protein 2 (MAP2) is of importance for neuronal, axonal, and dendritic generation, extension, and stabilization, as well as for the regulation of synaptic plasticity. OBJECTIVE: To investigate the antagonistic effects of natural-cerebrolysin-containing serum on beta amyloid protein 1-40 (Aβ1-40)-induced neurotoxicity from the standpoints of cell proliferation, synaptogenesis, and cytoskeleton formation (MAP2 expression). DESIGN, TIME AND SETTING: A paralleled, controlled, neural cell, and molecular biology experiment was performed at the Institute of Integrated Chinese and Western Medicine, Shenzhen Hospital, Southern Medical University between February 2006 and April 2008. MATERIALS: PC12 cells, derived from the rat central nervous system, were purchased from Shanghai Institute of Cell Biology, Chinese Academy of Sciences, China. A β1-40 was provided by Sigma, USA. Natural-cerebrolysin was provided by Shenzhen Institute of Integrated Chinese and Western Medicine, China. The natural-cerebrolysin was predominantly composed of Renshen (Radix Ginseng), Tianma (Rhizoma Gastrodiae), and Yixingye (Ginkgo Leaf) in a proportion of 1:2:2. Following conventional water extraction technology, an extract (1:20) was prepared. Each gram of extract equaled 20 grams of crude drug. In a total of 12 adult male New Zealand rabbits, six underwent intragastric administration of natural-cerebrolysin extract for 1 month to prepare natural-cerebrolysin-containing serum, and the remaining six rabbits received intragastric administration of physiological saline to prepare normal blank serum. METHODS: An AIzheimer's disease in vitro model was induced in PC12 cells using Aβ1-40. The cells were incubated with varying doses of natural-cerebrolysin-containing serum (2.5%, 5%, and 10%). Normal blank serum-treated PC12 cells served as a blank control group. MAIN OUTCOME MEASURES: Through the use of inverted phase contrast microscope, cell morphology and neurite growth were observed, neurite length was measured, and the percentage of neurite-positive cells was calculated. Cell proliferation rate was determined by MTT assay, and MAP 2 expression was detected by fluorescent immunocytochemistry. RESULTS: Following Aβ1-40 treatments, some PC12 cells were apoptotic/dying, and only a few short neurites were observed. Following interventions with natural-cerebrolysin-containing serum, the PC12 cells proliferated, there was an increased number of neurites, and neurite length was enhanced. After middle- and high-dose natural-cerebrolysin treatments, the percentage of neurite-positive cells, as well as the average length of neurites, was significantly greater than the normal blank serum-treated PC12 cells (P 〈 0.05 or P 〈 0.01). Compared with the blank control group, MAP2 expression in the Aβ1-40-treated PC12 cells was significantly inhibited, and the cell proliferation rate was significantly decreased (P 〈 0.01). Following incubations with natural-cerebrolysin-containing serum, MAP2 expression and cell proliferation rate in the PC12 cells were significantly increased in a dose-dependent manner, compared with treatments with blank control serum (P 〈 0.05 or P 〈 0.01 ). CONCLUSION: Natural-cerebrolysin exhibited antagonistic effects on neurotoxicity in Aβ1-40 induced Alzheimer's disease in vitro models. These effects were likely related to cell proliferation and the upregulation of intracellular MAP2 expression. 展开更多
关键词 natural-cerebrolysin Alzheimer's disease in vitro model NEUROTOXICITY neuroprotective effect amyloid beta protein 1-40
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