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Studying the co-evolution of information diffusion,vaccination behavior and disease transmission in multilayer networks with local and global effects
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作者 霍良安 武兵杰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期677-689,共13页
Today,with the rapid development of the internet,a large amount of information often accompanies the rapid transmission of disease outbreaks,and increasing numbers of scholars are studying the relationship between inf... Today,with the rapid development of the internet,a large amount of information often accompanies the rapid transmission of disease outbreaks,and increasing numbers of scholars are studying the relationship between information and the disease transmission process using complex networks.In fact,the disease transmission process is very complex.Besides this information,there will often be individual behavioral measures and other factors to consider.Most of the previous research has aimed to establish a two-layer network model to consider the impact of information on the transmission process of disease,rarely divided into information and behavior,respectively.To carry out a more in-depth analysis of the disease transmission process and the intrinsic influencing mechanism,this paper divides information and behavior into two layers and proposes the establishment of a complex network to study the dynamic co-evolution of information diffusion,vaccination behavior,and disease transmission.This is achieved by considering four influential relationships between adjacent layers in multilayer networks.In the information layer,the diffusion process of negative information is described,and the feedback effects of local and global vaccination are considered.In the behavioral layer,an individual's vaccination behavior is described,and the probability of an individual receiving a vaccination is influenced by two factors:the influence of negative information,and the influence of local and global disease severity.In the disease layer,individual susceptibility is considered to be influenced by vaccination behavior.The state transition equations are derived using the micro Markov chain approach(MMCA),and disease prevalence thresholds are obtained.It is demonstrated through simulation experiments that the negative information diffusion is less influenced by local vaccination behavior,and is mainly influenced by global vaccination behavior;vaccination behavior is mainly influenced by local disease conditions,and is less influenced by global disease conditions;the disease transmission threshold increases with the increasing vaccination rate;and the scale of disease transmission increases with the increasing negative information diffusion rate and decreases with the increasing vaccination rate.Finally,it is found that when individual vaccination behavior considers both the influence of negative information and disease,it can increase the disease transmission threshold and reduce the scale of disease transmission.Therefore,we should resist the diffusion of negative information,increase vaccination proportions,and take appropriate protective measures in time. 展开更多
关键词 information diffusion vaccination behavior disease transmission multilayer networks local and global effect
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Engineering tool for the evaluation of global IED effects 被引量:1
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作者 n.heider v.denefeld +1 位作者 a.steinbrenner a.holzwarth 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第2期214-221,共8页
The detonation of an IED near a military vehicle induces different damage effects on the vehicle and its occupants. There are local effects from fragments and projectiles but there are also global effects from a momen... The detonation of an IED near a military vehicle induces different damage effects on the vehicle and its occupants. There are local effects from fragments and projectiles but there are also global effects from a momentum transfer on the complete vehicle structure and a subsequent dynamical motion of the vehicle with phenomena like overturning or vehicle displacement from the road.Questions like this can be answered with numerical finite-element simulations but there is also the need for engineering tools that allow a quick and nearly instantaneous simulation of these phenomena. The following work presents an approach for a fast analysis of global IED effects on vehicles. The physical modelling is based on analytical formula and empirical data that describe the momentum transfer of a detonation on a nearby structure. This momentum is the initial condition for the calculation of the following vehicle motion and the simulation of vehicle dynamics and jump height.The software itself has a modern GUI that allows the generation of the vehicle structure and the threat scenario together with an interactive analysis of the simulation results.The engineering tool is validated with small size generic vehicle tests where jump height and the vehicle motion are compared. The software allows a detailed analysis of global IED effects and can be additionally used in an inverse mode for the analysis of incidents with the determination of used HE masses in an IED attack. 展开更多
关键词 IED 工具 工程 军事车辆 有限元模拟 评价 爆炸装置 车辆结构
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Relativistic Effects in the Global Positioning System
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作者 Neil Ashby (Department of Physics, University of Colorado, Boulder, Colorado 80309-0390 USA) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期199-237,共39页
The Global Positioning System (GPS) uses accurate atomic clocks in satellites and on the ground to provide world-wide position and time determination. These clocks have gravitational and motional frequency shifts whic... The Global Positioning System (GPS) uses accurate atomic clocks in satellites and on the ground to provide world-wide position and time determination. These clocks have gravitational and motional frequency shifts which are so large that, without properly accounting for relativistic effects, the system would not work. As a practical matter, therefore, many individuals who use the GPS need to understand how relativistic effects accounted for in the system. This paper discusses relativistic effects arising from both special relativity and general relativity, and how these effects are incorporated in GPS operations. Two introductory sections on kinematics in special and general relativity, respectively, are followed by a section which describes how relativistic effects should be accounted for. The concept of synchroization in the Earth-Centered Inertial frame is discussed in detail. Numerical and experimental examples are given, showing the sizes of the various effects. The treatment of special and general relativity is sufficiently complete that a person should be able to follow the development without much reference to external material, except that a few standard results have been quoted from textbooks without derivation. 展开更多
关键词 RELATIVITY global positioning system Sagnac effect Synchronization.
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Globalization's Effect on Today's Seafarers
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《交通建设与管理》 2004年第Z1期63-64,共2页
The Role of Manning AgenciesThe decline of the era where the people that owned the ships, managed the ships and hired their own crews saw the development of ship management firms and manning agencies. As the supply of... The Role of Manning AgenciesThe decline of the era where the people that owned the ships, managed the ships and hired their own crews saw the development of ship management firms and manning agencies. As the supply of seafarers moved from the traditional maritime nations to India, the Far East and Asia, the services of the manning agencies were gradually built into the system. 展开更多
关键词 globalization’s effect on Today’s Seafarers THAN
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Effect of Ocean Thermal Diffusivity on Global Warming Induced by Increasing Atmospheric CO_2
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作者 包宁 张学洪 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第4期421-430,共10页
A global mean ocean model including atmospheric heating, heat capacity of the mixed layer ocean, and vertical thermal diffusivity in the lower ocean, proposed by Cess and Goldenberg (1981), is used in this paper to st... A global mean ocean model including atmospheric heating, heat capacity of the mixed layer ocean, and vertical thermal diffusivity in the lower ocean, proposed by Cess and Goldenberg (1981), is used in this paper to study the sensitivity of global warming to the vertical diffusivity. The results suggest that the behaviour of upper ocean temperature is mainly determined by the magnitude of upper layer diffusivity and an ocean with a larger diffusivity leads to a less increase of sea surface temperature and a longer time delay for the global warming induced by increasing CO2 than that with smaller one. The global warming relative to four scenarios of CO2 emission assumed by Intergovernmental Panel of Climate Change (IPCC) is also estimated by using the model with two kinds of thermal diffusivities. The result shows that for various combinations of the CO2 emission scenarios and the diffusivities, the oceanic time delay to the global warming varies from 15 years to 70 years. 展开更多
关键词 effect of Ocean Thermal Diffusivity on global Warming Induced by Increasing Atmospheric CO2 CO
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Volatility Modelling of Global Financial Crises Effects on the Nigerian Banks
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作者 Maruf A. Raheem Timothy K. Samson 《Open Journal of Statistics》 2020年第2期303-324,共22页
The most appropriate heteroskedastic models for predicting volatility of daily stocks prices of 10 major Nigerian banks are proposed. The banks are Access, United Bank for Africa (UBA), Guaranty Trust, Skye, Diamond, ... The most appropriate heteroskedastic models for predicting volatility of daily stocks prices of 10 major Nigerian banks are proposed. The banks are Access, United Bank for Africa (UBA), Guaranty Trust, Skye, Diamond, Fidelity, Sterling,?Union, ETI and Zenith banks;and these are examined from 2004 to 2014.?The models employed are Autoregressive Conditional Heteroscedastic (ARCH(1)), Generalized Autoregressive Conditional Heteroscedastic (GARCH(1, 1)),?Exponential Generalized Autoregressive Conditional Heteroscedastic?(EGARCH(1, 1))?and Glosten, Jagananthan and Runkle-Generalized Autoregressive Conditional Heteroscedastic?(GJR-GARCH(1, 1)). The results show that all the?bank returns are highly leptokurtic, significantly skewed and thus non-normal across the four periods except for Fidelity bank during financial crises;findings similar to those of other global markets. Also noticed is the strong evidence for the presence of heteroscedasticity, and that volatility persistence during crisis?is?higher than before the crisis across the 10 banks, with that of UBA taking the lead, about 11 times higher during the crisis. The same with persistence?levels in volatility, which were relatively higher during financial crises across the ten banks compared to before the crises.?Findings further indicate that Asymmetric GARCH models outperformed the symmetric GARCH models, especially during the financial crises and post the crises. Thus with these findings, one could generally conclude that Nigerian banks’?returns are volatility persistent during and after the crises, and are characterized by leverage effects of negative and positive shocks during these periods. 展开更多
关键词 global Financial CRISIS Leverage effect NIGERIAN Stock Exchange VOLATILITY Clustering PERSISTENCE
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全球价值链的脱钩与反脱钩:来自中国制造业企业微观数据的经验证据 被引量:2
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作者 郭万山 滕飞 +1 位作者 侯翔瀚 李科霖 《中国科技论坛》 CSSCI 北大核心 2024年第4期74-83,136,共11页
本文基于中国制造业上市公司的微观数据和WIOD及亚行的世界投入产出表数据,考察美国的价值链脱钩策略对中国企业创新内在动力的激发效应和对中国全球价值链地位攀升的影响。研究发现:首先,美国的价值链脱钩策略对中国企业创新内在动力... 本文基于中国制造业上市公司的微观数据和WIOD及亚行的世界投入产出表数据,考察美国的价值链脱钩策略对中国企业创新内在动力的激发效应和对中国全球价值链地位攀升的影响。研究发现:首先,美国的价值链脱钩策略对中国企业创新内在动力存在显著的正向激发作用,且激发效应能够抵消遏制效应。其次,脱钩策略对中国全球价值链地位攀升的叠加效应显著为正,与产业上游度负相关,表明美国的脱钩策略并不会阻断中国全球价值链地位的攀升和产业技术水平的提高。最后,中国企业自主创新对FDI技术外溢的吸收和转化等“学习效应”过于依赖,存在“低质低效”的双低现象,降低了价值链地位攀升的效率。FDI对产业价值链地位有显著的提升作用,但对国内企业“高质高效”的自主创新具有抑制作用。本文结论为提高企业自主创新质量和效率以及价值链地位提供了政策启示。 展开更多
关键词 价值链脱钩 遏制效应 激发效应 全球价值链地位
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A Numerical Study of the Mechanism for the Effect of Northern Winter Arctic Ice Cover on the Global Short-Range Climate Evolution
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作者 倪允琪 张勤 李跃东 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第4期489-498,共10页
By using a nine-layer global spectral model involving fuller parameterization of physical processes, with a rhomboidal truncation at wavenumber 15, experiments are performed in terms of two numerical schemes, one with... By using a nine-layer global spectral model involving fuller parameterization of physical processes, with a rhomboidal truncation at wavenumber 15, experiments are performed in terms of two numerical schemes, one with long-term mean coverage of Arctic ice (Exp.1), the other without the ice (Exp.2). Results indicate that the Arctic region is a heat source in Exp.2 relative to the case in Exp.1. Under the influence of the polar heat source simulated, there still exist stationary wavetrains that produce WA-EUP and weak PNA patterns in Northern winter. That either the Arctic or the tropical heat source can cause identical climatic effects is due to the fact that the anomaly of the Arctic ice cover will directly induce a south-propagating wavetrain, and bring about the redistribution of the tropical heat source / sink. The redistribution is responsible for new wavetrains that will exert impact on the global climate. The simulation results bear out further that the polar region in Exp.2 as a heat source, can produce, by local forcing, a pair of positive and negative difference centers, which circle the Arctic moving eastwards. Observed in the Northern Hemisphere extratropics is a 40-50 day oscillation in relation to the moving pair, both having the same period. 展开更多
关键词 over A Numerical Study of the Mechanism for the effect of Northern Winter Arctic Ice Cover on the global Short-Range Climate Evolution
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Qualitative Considerations on the Influence of the Gases Water Vapor and Carbon Dioxide on the Global Environmental Temperature from the Point of View of Textbook Knowledge 被引量:1
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作者 Wolfram Vogelsberger 《Advances in Chemical Engineering and Science》 CAS 2023年第1期50-64,共15页
The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional ... The solar radiation that hits the Earth conditions the dynamic equilibrium that prevails on our planet. Consideration of basic physical-chemical knowledge shows that this equilibrium can be changed only by additional energy input or prolongation of the interaction time solar radiation—Earth matter. The contribution of H<sub>2</sub>O(g) and CO<sub>2</sub> to the protection of the earth against excessive warming is experimentally and by basic laws of nature secured. For a greenhouse effect, a part of the earth radiation must be radiated back to the earth and then into space. If one understands the earth radiation as radiation of a black body with the average global environmental temperature, from all vibrations normal modes of the gases H<sub>2</sub>O(g) and CO<sub>2</sub> only the bending mode of CO<sub>2</sub> with 4% of the solar constant can contribute beside the rotational modes of the water to the greenhouse effect. The contributions of the normal modes of H<sub>2</sub>O(g) and CO<sub>2</sub> to the heat capacity of the atmosphere are negligible. Therefore, in agreement with studies by K. &#197;ngstr&#246;m, CO<sub>2</sub> contributes only to the stabilization of the global environmental temperature. Whether the use of renewable energies can actually at least mitigate the increase of the environmental temperature is by no means certain but must be examined for each individual case. With certainty, this goal can only be achieved by reducing the energy consumption of mankind. 展开更多
关键词 global Temperature IRRADIATION Dynamic Equilibrium Heat Capacity Greenhouse effect
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中国文学走出去效果评估指标体系建设:原则与方法
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作者 李琴 《山东外语教学》 北大核心 2024年第1期103-113,共11页
在中华文化走出去战略引领下,中国文学翻译与传播事业如火如荼,逐渐由路径探索深入到提质增效阶段,文学走出去效果评估研究成为热点。本文依据拉斯韦尔传播过程“5W”模式厘析影响中国文学走出去效果的多种因素,利用德尔菲法和层次分析... 在中华文化走出去战略引领下,中国文学翻译与传播事业如火如荼,逐渐由路径探索深入到提质增效阶段,文学走出去效果评估研究成为热点。本文依据拉斯韦尔传播过程“5W”模式厘析影响中国文学走出去效果的多种因素,利用德尔菲法和层次分析法确立效果评估指标并赋以权重,最终建构一个中国文学走出去效果评估体系,以期为中国文学海外传播效果评估提供较为科学并实用的量具,为中国文学对外翻译实践提供参考。 展开更多
关键词 中国文学走出去 效果评估 指标体系 评估原则 评估方法
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“一带一路”倡议与全球价值链升级——基于沿线国家的实证数据 被引量:1
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作者 屠年松 郑雅哲 官波 《经济问题》 CSSCI 北大核心 2024年第5期52-60,共9页
基于2007—2020年“一带一路”沿线国家的样本数据,利用多期双重差分模型实证检验了“一带一路”倡议对沿线国家的价值链升级作用。研究结果证实:“一带一路”倡议对于沿线国家全球价值链发展具有显著正向影响。机制分析表明:“一带一... 基于2007—2020年“一带一路”沿线国家的样本数据,利用多期双重差分模型实证检验了“一带一路”倡议对沿线国家的价值链升级作用。研究结果证实:“一带一路”倡议对于沿线国家全球价值链发展具有显著正向影响。机制分析表明:“一带一路”倡议对沿线国家存在“虹吸效应”,有利于沿线国家的发展。此外,政策沟通对于倡议的推行具有积极的促进作用。研究结果不仅证实了倡议对于沿线国家价值链升级的正向影响,也论证了其中存在的影响机制,为未来进一步的研究提供了理论支撑和有益探索。 展开更多
关键词 “一带一路”倡议 全球价值链 空间溢出效应 多期双重差分
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基于GTAP模型的中缅印度洋新通道贸易效应研究
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作者 胡颖 陈洁筠 《云南财经大学学报》 CSSCI 北大核心 2024年第10期89-110,共22页
中国-缅甸-印度洋海公铁联运新通道,是从中国西南地区打通印度洋出海通道的必经之路,其发展与“一带一路”孟中印缅经济走廊建设和中国西部沿边开放紧密关联。从贸易网络、贸易依赖度、竞争性和互补性等方面探究通道开通后沿线国家和地... 中国-缅甸-印度洋海公铁联运新通道,是从中国西南地区打通印度洋出海通道的必经之路,其发展与“一带一路”孟中印缅经济走廊建设和中国西部沿边开放紧密关联。从贸易网络、贸易依赖度、竞争性和互补性等方面探究通道开通后沿线国家和地区间贸易规模、贸易结构和贸易壁垒的变动,揭示了沿线国家和地区贸易关系的特征和动态变化。根据运输成本对贸易的传导机制,采用GTAP模型,模拟预测中缅印度洋新通道在部分联通、全线贯通和路网形成三种不同情景下产生的贸易效应。研究发现:中缅印度洋新通道的开通将直接刺激沿线地区贸易规模增长,贸易条件显著改善,中国、缅甸和印度等国实际GDP和社会福利水平显著提升;随着物流成本下降和贸易网络深化,新通道促进贸易从高成本的域外地区向低成本的域内地区转移,重构区内贸易格局;新通道的开通将有利于推动中国与周边国家和地区形成产业链互补,促进区域经济一体化发展。 展开更多
关键词 中缅印度洋新通道 贸易效应 全球贸易分析(GTAP)模型
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反倾销嵌入全球生产网络的级联效应仿真研究
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作者 乔小勇 吴晓雪 +3 位作者 薛蕊 Claude Baron 沈煌南 赵乔 《管理科学学报》 CSSCI CSCD 北大核心 2024年第8期1-22,共22页
本研究将复杂网络理论应用于投入产出模型并将其引入宏观经济学生产函数理论模型,对反倾销嵌入全球生产网络的内在机理与其产生的级联效应展开探讨与仿真模拟分析.研究发现:基于网络视角与投入产出关系,反倾销冲击对中间产品的贸易抑制... 本研究将复杂网络理论应用于投入产出模型并将其引入宏观经济学生产函数理论模型,对反倾销嵌入全球生产网络的内在机理与其产生的级联效应展开探讨与仿真模拟分析.研究发现:基于网络视角与投入产出关系,反倾销冲击对中间产品的贸易抑制作用要明显大于最终产品,多次跨境的中间品将会累积增加反倾销带来的贸易成本;反倾销带来的行业引致需求量降低与出口贸易受到抑制以及行业与国家总产出水平的波动等影响,会沿着以中间品贸易为基础的全球生产网络中的投入产出关系进行传播,从而产生显著的级联效应,并且该效应会随着不同国家-部门节点之间的联系紧密程度(贸易量)的降低而衰减;反倾销产生的级联效应不仅涉及全球生产网络中直接关联节点即涉案国(调查国与被调查国)的国内上下游行业,而且波及间接关联节点即非涉案国的第三方国家和地区,进而影响全球多边贸易发展,同时,级联效应也阻碍了网络节点参与全球价值链生产分工,导致了节点隶属国(地区)的国内价值链被拉长;反倾销嵌入全球生产网络后,会通过整个生产网络产生总量波动效应,从而改变全球生产网络的拓扑结构,即全球生产网络变的相对稀疏、节点间网络距离拉长等. 展开更多
关键词 反倾销 贸易摩擦 政策冲击 全球生产网络 级联效应
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Simplified Penman-Monteith Equation Determined by Temperature-Based Global Radiation Data and Its Multilocal Validation under Subhumid Climatic Conditions in Hungary
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作者 Zoltán Varga-Haszonits Éva Szalka +3 位作者 Dávid Vasas Zsolt Giczi Pál Szakál Tamás Szakál 《Atmospheric and Climate Sciences》 2023年第4期455-465,共11页
The extent to which specific climatic factors influence evapotranspiration under subhumid conditions in Hungary was investigated. The reference evapotranspiration, calculated with the internationally accepted Penman-M... The extent to which specific climatic factors influence evapotranspiration under subhumid conditions in Hungary was investigated. The reference evapotranspiration, calculated with the internationally accepted Penman-Monteith equation proposed by FAO, was considered. The results show that the influence of radiation, which provides energy for evaporation, is the strongest factor and that the influence of global radiation alone is very strong. Taking into account that radiation was measured under rather limited conditions in space and time, global radiation was calculated using the Hargreaves method based on temperature. Accordingly, we have defined a formula based on temperature-based global radiation and verified the data obtained with the Penman-Monteith formula calculated for 14 meteorological stations. The verification gave good results, therefore the method can be used for practical purposes in the subhumid conditions of Hungary based on the data of the nearest meteorological station. 展开更多
关键词 effecting Factors Sensitivity Analysis global Radiation Multilocal Validation Estimation Error
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Refinement and Quantification of Terrain-Induced Effects on Global Gravity Data
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作者 Ojima I. Apeh Elochukwu C. Moka +1 位作者 Victus N. Uzodinma Elijah S. Ebinne 《International Journal of Geosciences》 2019年第5期513-526,共14页
The geodetic and geophysical applications of Earth Gravity Field parameters computed from Global Geopotential Models (GGMs) are quite on the increase despite the inherent commission and omission errors of these models... The geodetic and geophysical applications of Earth Gravity Field parameters computed from Global Geopotential Models (GGMs) are quite on the increase despite the inherent commission and omission errors of these models. In view of this, this study focuses on refining and quantifying terrain-induced effects on Bouguer gravity anomalies computed directly from a total of seven recent GGMs. In the study, the Residual Terrain Model (RTM) technique was used to estimate the residual terrain effects that were added to the GGM-computed Bouguer gravity anomalies at the sixty test points in Enugu State, Nigeria. The computed residual terrain effects range from -24.6 to 37.5 mgal while the percentage of the omission errors of the GGMs based on their Root-Mean-Square (RMS) differences ranges from 7.8% to 44.7%. It can be concluded that GGM-refined Bouguer gravity anomalies are better in accuracy than the unrefined GGM-computed Bouguer gravity anomalies and hence there is need for accurate height information in the development of GGMs. We, therefore, recommend that refined Bouguer gravity anomalies obtained from HUST-Grace2016s, EIGEN-6C4 and GECO that gave best improvement amongst the seven GGMs under consideration should be used to supplement the available terrestrial Bouguer anomalies for geodetic and geophysical applications within the study area. 展开更多
关键词 Bouguer Gravity ANOMALIES global GEOPOTENTIAL Models Refined Bouguer ANOMALIES Residual TERRAIN Model (RTM) effects
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数据要素市场化对中国企业全球价值链分工的影响
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作者 蒋诗 任妍 文春玲 《技术经济与管理研究》 北大核心 2024年第5期135-140,共6页
选取中国工业企业数据和海关贸易数据,实证考察数据要素市场化对企业全球价值链分工的影响以及作用机制。研究结果显示,数据要素市场化可显著促进企业深度参与全球价值链分工;机制检验结果表明,产业结构升级效应和技术创新效应是数据要... 选取中国工业企业数据和海关贸易数据,实证考察数据要素市场化对企业全球价值链分工的影响以及作用机制。研究结果显示,数据要素市场化可显著促进企业深度参与全球价值链分工;机制检验结果表明,产业结构升级效应和技术创新效应是数据要素市场化驱动企业深度参与全球价值链分工的重要渠道;异质性检验表明,数据要素市场化对非东部地区企业全球价值链分工的促进作用更明显。有鉴于此,应持续深化数据要素市场化改革、加快建设现代产业体系、大力发展数智经济核心产业、实施差异化发展战略,以期提高企业嵌入全球价值链分工体系的附加价值。 展开更多
关键词 数据要素市场化 企业全球价值链分工 产业结构升级效应 技术创新效应
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国内贸易网络与企业全球价值链地位——基于市场可达性的中介效应
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作者 徐晓莉 郭容含 《华东经济管理》 CSSCI 北大核心 2024年第4期38-47,共10页
现代经济生产与分工日渐网络化,促使国内贸易网络对企业全球价值链地位攀升的重要作用逐步凸显。文章基于2012—2022年我国上市公司和中国海关匹配数据,考察国内贸易网络对企业全球价值链地位的影响和作用机制。研究结果表明:国内贸易... 现代经济生产与分工日渐网络化,促使国内贸易网络对企业全球价值链地位攀升的重要作用逐步凸显。文章基于2012—2022年我国上市公司和中国海关匹配数据,考察国内贸易网络对企业全球价值链地位的影响和作用机制。研究结果表明:国内贸易网络对企业全球价值链地位具有显著促进作用;中介机制检验结果显示,市场可达性在国内贸易网络影响企业全球价值链地位过程中发挥中介作用;门槛效应检验发现,在市场可达性较高地区,国内贸易网络对企业全球价值链地位的促进作用更强;异质性检验表明,国内贸易网络对企业全球价值链地位的正向影响在高生产率企业和中低质量产品企业中更显著。据此,文章提出跨区域拓展与延伸国内贸易网络、制定差异化扶持策略、借助于现有交通网络深化市场可达性等对策建议,以期更好助力企业实现全球价值链地位攀升。 展开更多
关键词 国内贸易网络 市场可达性 企业全球价值链地位 中介效应 门槛效应
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健脾益肾推拿法治疗全面性发育迟缓的有效性研析
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作者 骆晓金 《中国医药科学》 2024年第3期103-106,共4页
目的 将健脾益肾推拿法用于全面性发育迟缓患儿,并分析其疗效。方法 选取2019年8月至2021年12月就诊于枣庄市立医院理疗科全面性发育迟缓的患儿60例为研究对象,根据单双号方式分为两组,每组各30例。对照组采取常规治疗,观察组联合健脾... 目的 将健脾益肾推拿法用于全面性发育迟缓患儿,并分析其疗效。方法 选取2019年8月至2021年12月就诊于枣庄市立医院理疗科全面性发育迟缓的患儿60例为研究对象,根据单双号方式分为两组,每组各30例。对照组采取常规治疗,观察组联合健脾益肾推拿法,对两组的全面发育情况、满意度等进行评估。结果 治疗后,两组大运动、精细动作、语言评分高于治疗前,且观察组高于对照组,差异有统计学意义(P <0.05)。治疗后,两组适应性、个人-社交、格赛尔发育量表(Gesell)总分高于治疗前,且观察组高于对照组,差异有统计学意义(P <0.05)。治疗后,两组粗大运动发育量表(GMFM-88)及婴儿到初中生社会能力量表(S-M)评分高于治疗前,且观察组高于对照组,差异有统计学意义(P <0.05)。观察组治疗总满意度为93.33%,高于对照组的73.33%,差异有统计学意义(P <0.05)。结论 健脾益肾推拿法可促进全面性发育迟缓患儿的全面发育,提升患儿的生活能力、运动能力等综合能力,有利于患儿的成长,并取得较高的满意度,值得临床推广。 展开更多
关键词 健脾益肾推拿法 全面性发育迟缓 粗大运动 精细运动 有效性 满意度
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Correlations between the Global Earth Healing and Global Consciousness Projects—Brain-Mind-Matter-Interactions through Physical Noise Generators
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作者 Marcus Schmieke 《Natural Science》 2023年第5期191-198,共8页
Inspired by Roger Nelson’s Global Consciousness Project (GCP), the Global Earth Healing Project (GEHP) uses a network of several hundred physical noise generators to amplify the combined intentions of their users in ... Inspired by Roger Nelson’s Global Consciousness Project (GCP), the Global Earth Healing Project (GEHP) uses a network of several hundred physical noise generators to amplify the combined intentions of their users in order to infuse positive affirmations into the global consciousness. As mentioned in the original study design, it was intended to use the GCP as a reference for the effectiveness of its activities. The data of the GEHP consisting of 21 events from 2013 to 2020 is analyzed and statistically compared to the data of the GCP. An astonishing synchronicity was observed, which suggests an interaction between the brain states of the observers and the physical noise generators of the GCP. 展开更多
关键词 global Consciousness Project global Consciousness Information Field Coherence PEAR Lab Quantum Entanglement Decline effect
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一种两阶段求解LED光谱匹配系数高效全局优化算法
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作者 王永军 吴贵文 +1 位作者 黄河 李同军 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第6期1591-1599,共9页
用单色发光二极管(LED)组份合成目标光谱在现实中有重要意义。当单色LED组成成份多、目标光谱合成精度要求高时,求解光谱组成成份的比例问题变成了超定方程组非负解的组合优化难题。智能优化类算法提高了解的全局最优性,但若没有利用目... 用单色发光二极管(LED)组份合成目标光谱在现实中有重要意义。当单色LED组成成份多、目标光谱合成精度要求高时,求解光谱组成成份的比例问题变成了超定方程组非负解的组合优化难题。智能优化类算法提高了解的全局最优性,但若没有利用目标函数的数学解析性质,其收敛速度慢,解的精度不高。梯度类算法收敛到局部解的速度快且精度高,但至今没有成熟理论技术求解非凸优化全局最优解,且问题中非负解的要求限制了该类算法的收敛速度。同时,目标函数的最小二乘信息在求解时没有得到充分利用。基于目标函数的数学可解析性、表现形式的二次非线性格式、最终解的非负要求,提出了一种两阶段优化算法LLR_LBFGS。第一阶段进行无约束的线性拟合,得到目标函数的最小二乘近似理论解,第二阶段借助带约束的拟牛顿方法LBFGS进一步求取问题的非负全局最优解。以标准目标光谱CIE-A、CIE-D65、CIE-D50、CIE-D55、CIE-D75的最佳拟合为研究对象,对比了新方法与拉索回归算法(LASSO)、岭回归算法(RIDGE)、差分进化算法(DE)、粒子群算法(PSO)及遗传算法(GA)的求解精度和运行速度,以及决策系数R 2。基于实际工业案例的数值结果表明,LLR_LBFGS能够较快地锁定全局解的范围,收敛速度更快;能够借助目标函数的数学可解析性提高解的精度。两个阶段的衔接融合能够获得较好的全局最优解的起始点和高精度的最优解。该方法对解决LED光谱拟合问题潜力大,有普适性。基于该设计思路,可以在算法的两个阶段中,组合设计更多、更灵活的光谱配比解决方案。这对于求取LED光谱匹配最优解的智能优化类方法改善效果有较好的启发意义。 展开更多
关键词 光谱学 LED光谱匹配 线性拟合 LBFGS 高效 全局优化
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