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Irregular seismic data reconstruction based on exponential threshold model of POCS method 被引量:16
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作者 高建军 陈小宏 +2 位作者 李景叶 刘国昌 马剑 《Applied Geophysics》 SCIE CSCD 2010年第3期229-238,292,293,共12页
Irregular seismic data causes problems with multi-trace processing algorithms and degrades processing quality. We introduce the Projection onto Convex Sets (POCS) based image restoration method into the seismic data... Irregular seismic data causes problems with multi-trace processing algorithms and degrades processing quality. We introduce the Projection onto Convex Sets (POCS) based image restoration method into the seismic data reconstruction field to interpolate irregularly missing traces. For entire dead traces, we transfer the POCS iteration reconstruction process from the time to frequency domain to save computational cost because forward and reverse Fourier time transforms are not needed. In each iteration, the selection threshold parameter is important for reconstruction efficiency. In this paper, we designed two types of threshold models to reconstruct irregularly missing seismic data. The experimental results show that an exponential threshold can greatly reduce iterations and improve reconstruction efficiency compared to a linear threshold for the same reconstruction result. We also analyze the anti- noise and anti-alias ability of the POCS reconstruction method. Finally, theoretical model tests and real data examples indicate that the proposed method is efficient and applicable. 展开更多
关键词 Irregular missing traces seismic data reconstruction POCS threshold model.
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Tail Behavior of Threshold Models with Innovations in the Domain of Attraction of the Double Exponential Distribution
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作者 Aliou Diop Saliou Diouf 《Applied Mathematics》 2011年第5期515-520,共6页
We consider a two-regime threshold autoregressive model where the driving noises are sequences of independent and identically distributed random variables with common distribution function which belongs to the domain ... We consider a two-regime threshold autoregressive model where the driving noises are sequences of independent and identically distributed random variables with common distribution function which belongs to the domain of attraction of double exponential distribution. If in addition, for each and where denotes the convolution of the distribution function and we determine the tail behavior of the process and give the exact values of the coefficient. 展开更多
关键词 TAIL Behavior Domain of ATTRACTION CONVOLUTION TAILS Stochastic RECURRENCE Equation threshold AUTOREGRESSIVE model
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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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Maneuvering target tracking using threshold interacting multiple model algorithm
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作者 徐迈 山秀明 徐保国 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期440-444,共5页
To avoid missing track caused by the target maneuvers in automatic target tracking system, a new maneuvering target tracking technique called threshold interacting multiple model (TIMM) is proposed. This algorithm i... To avoid missing track caused by the target maneuvers in automatic target tracking system, a new maneuvering target tracking technique called threshold interacting multiple model (TIMM) is proposed. This algorithm is based on the interacting multiple model (IMM) method and applies a threshold controller to improve tracking accuracy. It is also applicable to other advanced algorithms of IMM. In this research, we also compare the position and velocity root mean square (RMS) errors of TIMM and IMM algorithms with two different examples. Simulation results show that the TIMM algorithm is superior to the traditional IMM alzorithm in estimation accuracy. 展开更多
关键词 maneuvering target tracking Kalman filter interacting multiple model (IMM) threshold interacting multiple model (TIMM)
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Discussion on the paper “Analyzing short time series data from periodically fluctuating rodent populations by threshold models: A nearestblock bootstrap approach”
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作者 LI W.K.& LI GuoDong Department of statistics and Actuarial Science,University of Hong Kong,Pokfulam Road,Hong Kong,China 《Science China Mathematics》 SCIE 2009年第6期1109-1110,共2页
The authors are to be congratulated for an innovative paper in terms of both modelling methodology and subject matter significance. The analysis of short time series is known to be
关键词 time Discussion on the paper A nearestblock bootstrap approach Analyzing short time series data from periodically fluctuating rodent populations by threshold models GARCH data
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Discussion on the paper “Analyzing short time series data from periodically fluctuating rodent populations by threshold models: A nearestblock bootstrap approach”
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作者 HALL Peter 《Science China Mathematics》 SCIE 2009年第6期1107-1108,共2页
This is a very attractive article. It combines fascinating new methodology with a most interesting dataset, and a highly motivating presentation. However, despite the many
关键词 time A nearestblock bootstrap approach Analyzing short time series data from periodically fluctuating rodent populations by threshold models Discussion on the paper data
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Short Term Load Forecasting Using Subset Threshold Auto Regressive Model
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作者 孙海健 《Journal of Southeast University(English Edition)》 EI CAS 1999年第2期78-83,共6页
The subset threshold auto regressive (SSTAR) model, which is capable of reproducing the limit cycle behavior of nonlinear time series, is introduced. The algorithm for fitting the sampled data with SSTAR model is pr... The subset threshold auto regressive (SSTAR) model, which is capable of reproducing the limit cycle behavior of nonlinear time series, is introduced. The algorithm for fitting the sampled data with SSTAR model is proposed and applied to model and forecast power load. Numerical example verifies that desirable accuracy of short term load forecasting can be achieved by using the SSTAR model. 展开更多
关键词 power load forecasting subset threshold auto regressive model
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Hormesis has emerged as a more common and fundamental dose-response model than the threshold or linear-no-threshold(LNT) models 被引量:6
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作者 Edward J. Calabrese Lu Rong-zhu 《毒理学杂志》 CAS CSCD 北大核心 2006年第2期117-118,共2页
在回顾传统的有阈和线性无阈的剂量-反应关系的基础上,分析此类该模型被毒理学领域认同的主要原因和其在预测低剂量效应中的缺陷,进而提出了高剂量接触呈现抑制效应,而低剂量却呈现促进或刺激作用这一全面的激效兴奋性剂量-反应关系,弥... 在回顾传统的有阈和线性无阈的剂量-反应关系的基础上,分析此类该模型被毒理学领域认同的主要原因和其在预测低剂量效应中的缺陷,进而提出了高剂量接触呈现抑制效应,而低剂量却呈现促进或刺激作用这一全面的激效兴奋性剂量-反应关系,弥补了现有模型的不足,并充分论证这种激效性剂量-反应关系在不同种属、接触因素和生物学终点中的普遍性,并探讨了不同物质的激效兴奋作用的可能机制以及激效兴奋模型的三大优点,最后提出了激效模型谋求广泛接受的现实困难和发展趋势。 展开更多
关键词 激效作用 兴奋效应 剂量-反应关系 有阈模型 线性无阈模型
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Error Threshold of Fully Random Eigen Model 被引量:1
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作者 李多芳 曹天光 +3 位作者 耿金鹏 乔丽华 顾建中 展永 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期170-173,共4页
Species evolution is essentially a random process of interaction between biological populations and their environ- ments. As a result, some physical parameters in evolution models are subject to statistical fluctuatio... Species evolution is essentially a random process of interaction between biological populations and their environ- ments. As a result, some physical parameters in evolution models are subject to statistical fluctuations. In this work, two important parameters in the Eigen model, the fitness and mutation rate, are treated as Gaassian dis- tributed random variables simultaneously to examine the property of the error threshold. Numerical simulation results show that the error threshold in the fully random model appears as a crossover region instead of a phase transition point, and &s the fluctuation strength increases the crossover region becomes smoother and smoother. Furthermore, it is shown that the randomization of the mutation rate plays a dominant role in changing the error threshold in the fully random model, which is consistent with the existing experimental data. The implication of the threshold change due to the randomization for antiviral strategies is discussed. 展开更多
关键词 Error threshold of Fully Random Eigen model
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Threshold autoregression models for forecasting El Nino events
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作者 Pu Shuzhen and Yu Huiling First Institute of Oceanography, State Oceanic Administration, Qingdao, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第1期61-67,共7页
-In this paper, monthly mean SST data in a large area are used. After the spacial average of the data is carried out and the secular monthly means are substracted, a time series (Jan. 1951-Dec. 1985) of SST anomalies ... -In this paper, monthly mean SST data in a large area are used. After the spacial average of the data is carried out and the secular monthly means are substracted, a time series (Jan. 1951-Dec. 1985) of SST anomalies of the cold tongue water area in the eastern tropical Pacific Ocean is obtained. On the basis of the time series, an autoregression model, a self-exciting threshold autoregression model and an open loop autoregression model are developed respectively. The interannual variations are simulated by means of those models. The simulation results show that all the three models have made very good hindcasting for the nine El Nino events since 1951. In order to test the reliability of the open loop threshold model, extrapolated forecast was made for the period of Jan. 1986-Feb. 1987. It can be seen from the forecasting that the model could forecast well the beginning and strengthening stages of the recent El Nino event (1986-1987). Correlation coefficients of the estimations to observations are respectively 0. 84, 0. 88 and 0. 89. It is obvious that all the models work well and the open loop threshold one is the best. So the open loop threshold autoregression model is a useful tool for monitoring the SSTinterannual variation of the cold tongue water area in the Eastern Equatorial Pacific Ocean and for estimating the El Nino strength. 展开更多
关键词 Nino EI SSTA threshold autoregression models for forecasting El Nino events EL
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Threshold Dynamics of the Stochastic SIRC Epidemic Model 被引量:1
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作者 Guangyang Zhang 《Journal of Applied Mathematics and Physics》 2018年第12期2498-2517,共20页
In this paper, we discuss the dynamics of a stochastic SIRC epidemic model with infection rate affected by white noise. We prove that this stochastic model has a unique nonnegative solution globally. A threshold is id... In this paper, we discuss the dynamics of a stochastic SIRC epidemic model with infection rate affected by white noise. We prove that this stochastic model has a unique nonnegative solution globally. A threshold is identified. When the noise is small, the solution of the stochastic model converges to the disease-free equilibrium point of the deterministic model if , which means the basic reproductive number of the stochastic model. And if , the solution of the stochastic model fluctuates around the epidemic equilibrium of the deterministic model. When the noise is large, the disease tends to extinction. The results are illustrated by computer simulations. 展开更多
关键词 STOCHASTIC SIRC model STABILITY threshold PERSISTENCE in Mean The ENDEMIC EQUILIBRIUM
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On a Class of Dual Model with Divided Threshold 被引量:1
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作者 Yuzhen Wen 《Advances in Pure Mathematics》 2011年第3期54-58,共5页
In this paper, we consider the dual of the generalized Erlang (n) risk model under a threshold dividend strategy. We derive an integrodifferential equation satisfied by the expectation of the discounted dividends unti... In this paper, we consider the dual of the generalized Erlang (n) risk model under a threshold dividend strategy. We derive an integrodifferential equation satisfied by the expectation of the discounted dividends until ruin. The case when profits follow an exponential distribution is solved. 展开更多
关键词 threshold STRATEGY DUAL RISK model GENERALIZED ERLANG (n) RISK Process
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Empirical Study of "Double Threshold" Modified Model on New Product Diffusion
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作者 LIU Dan SHENG Qiran XIN Zhanhong CAO Jiantong 《China Communications》 SCIE CSCD 2014年第12期44-53,共10页
The innovations actually diffuse among social network nowadays.Individual heterogeneity,interactions between individuals and network topology influence a lot.We established a "double threshold" modified mode... The innovations actually diffuse among social network nowadays.Individual heterogeneity,interactions between individuals and network topology influence a lot.We established a "double threshold" modified model and took the number of neighbors,neighbors' adoption and the cost-benefit parameters as crucial influencing factors.The diffusion of DaLingTong(CDMA450)products in MeiShan city of SiChuan province during 2004 to 2007 has been used to verity the model on Matlab.The validation results fit the actual diffusion pattern of DaLingTong(CDMA450) products very well.The results indicate that there exists a "tipping point(threshold)" in the process of innovation diffusion.If the initial adoption quantity is larger than the tipping point,then the product will spread to a large portion of people,otherwise is will collapse to zero.The model can effectively predict the diffusion of new products,and can influence the diffusion process by changing the value of the parameters. 展开更多
关键词 innovation diffusion threshold innovation model empirical study social network
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The relation between a microscopic threshold-force model and macroscopic models of adhesion
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作者 Srivatsan Hulikal Kaushik Bhattacharya Nadia Lapusta 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第3期508-515,共8页
This paper continues our recent work on the relationship between discrete contact interactions at the microscopic scale and continuum contact interactions at the macroscopic scale (Hulikal et al., J. Mech. Phys. Solid... This paper continues our recent work on the relationship between discrete contact interactions at the microscopic scale and continuum contact interactions at the macroscopic scale (Hulikal et al., J. Mech. Phys. Solids 76, 144-161, 2015). The focus of this work is on adhesion. We show that a collection of a large number of discrete elements governed by a threshold-force based model at the microscopic scale collectively gives rise to continuum fracture mechanics at the macroscopic scale. A key step is the introduction of an efficient numerical method that enables the computation of a large number of discrete contacts. Finally, while this work focuses on scaling laws, the methodology introduced in this paper can also be used to study rough-surface adhesion. 展开更多
关键词 ADHESION threshold-force model Johnson-Kendall-Roberts (JKR) theory FRACTURE Fast Multipole Method
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Benefit Analysis of Chemical Fertilizer Input for Staple Grain Production Based on Threshold Panel Data Model
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作者 Tengda ZUO Wan NIE 《Asian Agricultural Research》 2018年第9期1-5,8,共6页
Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benef... Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benefits,it compared the effects of chemical fertilizer input on farmers' income. It reached the conclusion that the chemical fertilizer input efficiency has deviated from the optimal level. Thus,only by increasing the marginal productivity of chemical fertilizers,may it be able to increase farmers' income. 展开更多
关键词 化肥投入 粮食产量 农业 计算方法
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Application of the Mechanical Threshold Stress Model to Large Strain Processing
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作者 Paul S. Follansbee 《Materials Sciences and Applications》 2022年第5期300-316,共17页
Large-strain deformations introduce several confounding factors that affect the application of the Mechanical Threshold Stress model. These include the decrease with the increasing stress of the normalized activation ... Large-strain deformations introduce several confounding factors that affect the application of the Mechanical Threshold Stress model. These include the decrease with the increasing stress of the normalized activation energy characterizing deformation kinetics, the tendency toward Stage IV hardening at high strains, and the influence of crystallographic texture. Minor additions to the Mechanical Threshold Stress model are introduced to account for variations of the activation energy and the addition of Stage IV hardening. Crystallographic texture cannot be modeled using an isotropic formulation, but some common trends when analyzing predominantly shear deformation followed by uniaxial deformation are described. Comparisons of model predictions with measurements in copper processed using Equal Channel Angular Pressing are described. 展开更多
关键词 Mechanical threshold Stress model Large-Strain Deformations ECAP Stress-Strain Curves Shear Deformations Activation Energy STRAIN-HARDENING
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数字经济对体育产业高质量发展的影响——基于中介模型和门槛模型的检验 被引量:3
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作者 苏伟洲 肖丹 +2 位作者 谭宏 李坤雨 车召丽 《上海体育大学学报》 北大核心 2024年第1期94-104,共11页
对我国19个省级行政区2012—2021年的面板数据进行实证分析,通过建立中介模型和门槛模型探究数字经济与我国体育产业高质量发展的关系。结果显示:①在固定效应模型的基础上进行实证分析发现,数字经济对体育产业高质量发展产生推动作用;... 对我国19个省级行政区2012—2021年的面板数据进行实证分析,通过建立中介模型和门槛模型探究数字经济与我国体育产业高质量发展的关系。结果显示:①在固定效应模型的基础上进行实证分析发现,数字经济对体育产业高质量发展产生推动作用;②在数字经济促进体育产业高质量发展过程中,产业结构作为中介变量、科技创新作为调节变量在其中起到相应的促进作用;③数字经济与体育产业高质量发展之间显著存在产业结构一阶门槛和科技创新二阶门槛效应。提出:应从提升数字经济发展水平、优化产业结构以及提升科技创新水平等方面促进体育产业高质量发展,推进社会主义现代化体育强国建设。 展开更多
关键词 体育产业高质量发展 数字经济 产业结构 科技创新 中介模型 门槛模型
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Reliability modeling of mutual DCFP considering failure physical dependency
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作者 CHEN Ying YANG Tianyu WANG Yanfang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1063-1073,共11页
Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has bee... Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has been widely studied.Electronic system may experience mutual effects of degradation and shocks,they are considered to be interdependent.Both the degradation and the shock processes will decrease the limit of system and cause cumulative effect.Finally,the competition of hard and soft failure will cause the system failure.Based on the failure mechanism accumulation theory,this paper constructs the shock-degradation acceleration and the threshold descent model,and a system reliability model established by using these two models.The mutually DCFP effect of electronic system interaction has been decomposed into physical correlation of failure,including acceleration,accumulation and competition.As a case,a reliability of electronic system in aeronautical system has been analyzed with the proposed method.The method proposed is based on failure physical evaluation,and could provide important reference for quantitative evaluation and design improvement of the newly designed system in case of data deficiency. 展开更多
关键词 electronic system dependent competing failure process(DCFP) failure physical dependency threshold descent model competition failure modes
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The Expected Discounted Tax Payments on Dual Risk Model under a Dividend Threshold 被引量:1
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作者 Zhang Liu Aili Zhang Canhua Li 《Open Journal of Statistics》 2013年第2期136-144,共9页
In this paper, we consider the dual risk model in which periodic taxation are paid according to a loss-carry-forward system and dividends are paid under a threshold strategy. We give an analytical approach to derive t... In this paper, we consider the dual risk model in which periodic taxation are paid according to a loss-carry-forward system and dividends are paid under a threshold strategy. We give an analytical approach to derive the expression of gδ(u) (i.e. the Laplace transform of the first upper exit time). We discuss the expected discounted tax payments for this model and obtain its corresponding integro-differential equations. Finally, for Erlang (2) inter-innovation distribution, closedform expressions for the expected discounted tax payments are given. 展开更多
关键词 DUAL Risk model EXPECTED Discounted TAX Payments DIVIDEND threshold Strategy
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知识产权国内贸易对“双循环”有效联动的影响效应 被引量:1
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作者 顾晓燕 朱玮玮 《经济问题》 北大核心 2024年第3期8-15,共8页
基于知识产权国内贸易、“双循环”有效联动的时空演化特征分析发现,二者发展变化具有显著的内在逻辑一致性。理论分析认为,知识产权国内贸易可以通过加快高水平自主创新、激发高品质消费需求等,对“双循环”有效联动产生显著的促进作... 基于知识产权国内贸易、“双循环”有效联动的时空演化特征分析发现,二者发展变化具有显著的内在逻辑一致性。理论分析认为,知识产权国内贸易可以通过加快高水平自主创新、激发高品质消费需求等,对“双循环”有效联动产生显著的促进作用。进一步利用2001—2020年中国省级面板数据开展的计量检验结果表明,第一,知识产权国内贸易对“双循环”有效联动具有积极促进作用;第二,由于知识产权国内贸易、“双循环”有效联动水平存在显著的空间溢出效应,因此,知识产权国内贸易对“双循环”有效联动的促进作用不仅发生在本地区,而且对相邻地区的“双循环”有效联动也有积极促进效应;第三,知识产权国内贸易对“双循环”有效联动的促进作用,因各地区对外开放程度、人力资本水平、城镇化水平、消费水平和知识产权保护水平的差异而存在一定的“门槛特征”。上述研究不仅有助于深化认识知识产权国内贸易对“双循环”有效联动的现实影响和作用机制,而且对于如何通过加强知识产权国内贸易推动“双循环”互促互进也有重要的政策意义。 展开更多
关键词 知识产权国内贸易 “双循环”有效联动 空间计量模型 面板门槛模型
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