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Correction models of Reynolds number effects for through-flow method in axial compressors
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作者 Xiaochen WANG Chunwei GU 《Chinese Journal of Aeronautics》 2026年第1期78-94,共17页
Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages ha... Aerodynamic performances of axial compressors are significantly affected by variation of Reynolds number in aero-engines.In the design and analysis of compressors,previous correction methods for cascades and stages have difficulties in predicting comprehensively Reynolds number effects on airfoils,matching and characteristics curves.This study proposes Re-correction models for loss,deviation angle and endwall blockage based on classical theories and cascade tests,and loss and deviation models show good agreement in test data of NACA65 and C4 cascades.Throughflow method considering Reynolds number effects is developed by integrating the correction models into a verified Streamline Curvature(SLC)tool.A three-stage axial compressor is investigated through SLC and CFD methods from design Reynolds number(Red=2106)to low Re=4104,and the numerical methods are validated with test data of characteristic curves and spanwise distributions at Red.With Re reduction,SLC method with correction models well predicts variation in overall performances compared with CFD calculations and Wassell's model.Streamwise and spanwise matching such as total pressure and loss distributions in SLC predictions are basically consistent with those in CFD results at near-stall points under design and low Reynolds numbers.SLC and CFD methods share similar detections of stall risks in the third stage(Stg3),and their analyses of diffusion processes deviate to some extent due to different predictions in separated endwall flow.The correction models can be adopted to consider Reynolds number effects in through-flow design and analysis of axial compressors. 展开更多
关键词 Axial compressor Reynolds number effects correction model Through-flow method Aerodynamic performance
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toGC:A pipeline to correct gene model for functional excavation of dark GPCRs in Phytophthora sojae
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作者 Min Qiu Chun Yan +6 位作者 Huaibo Li Haiyang Zhao Siqun Tu Yaru Sun Saijiang Yong Ming Wang Yuanchao Wang 《Journal of Integrative Agriculture》 2026年第1期150-156,共7页
The accuracy of genomic annotation is crucial for subsequent functional investigations;however,computational protocols used in high-throughput annotation of open reading frames(ORFs)can introduce inconsistencies.These... The accuracy of genomic annotation is crucial for subsequent functional investigations;however,computational protocols used in high-throughput annotation of open reading frames(ORFs)can introduce inconsistencies.These inconsistencies,which lead to non-uniform extension or truncation of sequence ends,pose challenges for downstream analyses.Existing strategies to rectify these inconsistencies are time-consuming and labor-intensive,lacking specific approaches.To address this gap,we developed to GC,a tool that integrates genomic annotation with RNA-seq datasets to rectify annotation inconsistencies.Using to GC,we achieved an accuracy of nearly 100%accuracy in correcting inconsistencies in published Phytophthora sojae ORFs.We applied this innovative pipeline to the GPCR-bigrams gene family,which was predicted to have 42 members in the P.sojae genome but lacked experimental validation.By employing to GC,we identified 32 GPCR-bigram ORFs with inconsistencies between previous annotations and to GC-corrected sequences.Notably,among these were 5 genes(GPCR-TKL9,GPCR-TKL15,GPCR-PDE3,GPCR-AC3,and GPCR-AC4)showed substantial inconsistencies.Experimental gene annotation confirmed the effectiveness of to GC,as sequences obtained through cloning matched those annotated by to GC.Importantly,we discovered two novel GPCRs(GPCR-AC3 and GPCR-AC4),which were previously mispredicted as a single gene.CRISPR/Cas9-mediated knockout experiments revealed the involvement of GPCR-AC4 but not GPCR-AC3 in oospore production,further confirming their status as two separate genes.In addition to P.sojae,the reliability of the to GC pipeline in Phytophthora capsici and Pythium ultimum further emphasizes the robustness of this pipeline.Our findings highlight the utility of to GC for reliable gene model correction,facilitating investigations into biological functions and offering potential applications in diverse species analyses. 展开更多
关键词 gene model correction TRANSCRIPTOME open reading frames G-protein coupled receptors
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Correction of Corporation Value Assessment Model Based on Corporate Social Responsibility
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作者 贠晓兰 《Agricultural Science & Technology》 CAS 2017年第4期736-739,共4页
The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate a... The performance of corporate social responsibility is conducive to the con- tinuous improvement of their profitability, and promotes the upgrading of corporation value. However, it is difficult to confirm, calculate and check the costs and benefits brought by the implementation of corporate social responsibility under the current ac- counting theory system, so it is difficult to estimate whether the fulfillment of corpo- rate social responsibility has any effects on the corporation value assessment. Therefore, based on corporate social responsibility, the correction mode of corpora- tion value assessment is put forward. 展开更多
关键词 Corporation value Social responsibility Assessment model correction model
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An Online Model Correction Method Based on an Inverse Problem:Part I—Model Error Estimation by Iteration 被引量:3
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作者 XUE Haile SHEN Xueshun CHOU Jifan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第10期1329-1340,共12页
Errors inevitably exist in numerical weather prediction (NWP) due to imperfect numeric and physical parameterizations. To eliminate these errors, by considering NWP as an inverse problem, an unknown term in the pred... Errors inevitably exist in numerical weather prediction (NWP) due to imperfect numeric and physical parameterizations. To eliminate these errors, by considering NWP as an inverse problem, an unknown term in the prediction equations can be estimated inversely by using the past data, which are presumed to represent the imperfection of the NWP model (model error, denoted as ME). In this first paper of a two-part series, an iteration method for obtaining the MEs in past intervals is presented, and the results from testing its convergence in idealized experiments are reported. Moreover, two batches of iteration tests were applied in the global forecast system of the Global and Regional Assimilation and Prediction System (GRAPES-GFS) for July-August 2009 and January-February 2010. The datasets associated with the initial conditions and sea surface temperature (SST) were both based on NCEP (National Centers for Environmental Prediction) FNL (final) data. The results showed that 6th h forecast errors were reduced to 10% of their original value after a 20-step iteration. Then, off-line forecast error corrections were estimated linearly based on the 2-month mean MEs and compared with forecast errors. The estimated error corrections agreed well with the forecast errors, but the linear growth rate of the estimation was steeper than the forecast error. The advantage of this iteration method is that the MEs can provide the foundation for online correction. A larger proportion of the forecast errors can be expected to be canceled out by properly introducing the model error correction into GRAPES-GFS. 展开更多
关键词 model error past data inverse problem error estimation model correction GRAPES-GFS
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Research on the Relationship between Income and Consumption of the Urban Residents in Hunan Province on the Basis of Error Correction Model 被引量:1
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作者 CHEN Hui-min 《Asian Agricultural Research》 2011年第1期51-54,共4页
By using error correction model, I conduct co-integration analysis on the research of the relationship between the per capita practical consumption and per capita practical disposable income of urban residents in Huna... By using error correction model, I conduct co-integration analysis on the research of the relationship between the per capita practical consumption and per capita practical disposable income of urban residents in Hunan Province from 1978 to 2009. The results show that there is a co-integration relationship between the per capita practical consumption and the practical per capita disposable income of urban residents, and based on these, the corresponding error correction model is established. Finally, corresponding countermeasures and suggestions are put forward as follows: broaden the income channel of urban residents; create goods consuming environment; perfect socialist security system. 展开更多
关键词 Residential income CO-INTEGRATION Error correction model China
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Parameters Sensitivity Analysis and Correction for Concrete Damage Plastic Model 被引量:1
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作者 Yaqin Jiang Pengfei Xu +1 位作者 Chengzhi Wang Dianshu Liu 《Journal of Beijing Institute of Technology》 EI CAS 2018年第1期103-108,共6页
In order to understand the effect of hardening ductility parameters and softening ductility parameters of the concrete damage plastic model in LS-DYNA,a sensitivity and reliability analysis of these parameters through... In order to understand the effect of hardening ductility parameters and softening ductility parameters of the concrete damage plastic model in LS-DYNA,a sensitivity and reliability analysis of these parameters through a convenient cube unit test was conducted. The results showed that the peak strength strain was independent of the hardening ductility parameter DH,but affected by AH,BH,and CH. The softening ductility was mainly related to the softening ductility parameter AS,but not affected by the damage ductility exponent BS. In case that the model with default parameters failed to match the AS-controlled damage softening phase,an optimized model with an AS correction was developed. The corrected model with the AS value of 2 matched well with the code model,and exhibited good feasibility in predicting the stress-strain curve of different grades of concrete. Moreover,the practicability of the corrected model was further validated by the conventional triaxial test. The simulated curve exhibited favorable consistence with the trial curve. Therefore,the model with parameter correction could provide a prospective reference for predicting the mechanical properties of concrete. 展开更多
关键词 damage-plastic model concrete sensitivity analysis parameter correction
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Higher-order Knudsen's permeability correction model for rarefied gas in micro-scale channels 被引量:1
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作者 Lu Yinbin 《Natural Gas Industry B》 2019年第5期502-508,共7页
Rarefaction effect appears when gas flows in micro/nano channels,so it is difficult to accurately predict real gas flow rate by using the classical theory.It is necessary to establish a more accurate and universal per... Rarefaction effect appears when gas flows in micro/nano channels,so it is difficult to accurately predict real gas flow rate by using the classical theory.It is necessary to establish a more accurate and universal permeability correction model to describe the flow behavior of rarefied gas.In this work,the gas flow in a plate micro-scale channel was numerically simulated using R26 moment method,and the simulation results were compared with those of the direct simulation Monte Carlo method(DSMC method)and R13 moment method.Then,a gas permeability correction model for plate micro-scale channels and circular micro-scale channels was established based on the simulation results of the R26 moment method,and used to describe the flow behavior of rarefied gas in micro-scale channels.Finally,the gas permeability correction co-efficient for different Knudsen numbers was calculated and compared with the prediction results of the Tang model,the available experimental data and the solution of linearized Boltzmann equation.The following research results were obtained.First,when the R26 moment method is used to describe the rarefaction effect of gas,its result is accordant with the calculation result of the DSMC method,and its calculation accuracy is higher than that of R13 moment method.Second,the gas permeability correction coefficient which is calculated by using the higher-order Knudsen's gas permeability correction model for plate micro-scale channels is in accordance with the experimental data and the solution of linearized Boltzmann equation.Third,the gas permeability correction coefficient which is calculated by using the higher-order Knudsen's gas permeability correction model for circular micro-scale channels is accordant with the solution of linearized Boltzmann equation.In conclusion,this higher-order Knudsen's gas permeability correction model is advantageous with high prediction precision and universality,and it can be used to describe the rarefaction effect of gas in micro/nano-scale channels. 展开更多
关键词 Micro-scales Rarefied gas Gas permeability correction model Knudsen number Moment method Prediction precision UNIVERSALITY
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Relationship Between Agricultural Credits and Agricultural Economy Based on Error Correct Model in Heilongjiang Province
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作者 XIN Liqiu LI Yanqiu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期75-78,共4页
Heilongjiang is a large agriculture province.Problems of agriculture,rural areas and farmers are urgent to be solved.The development of agriculture needs the support of agricultural credits,because finance is the cent... Heilongjiang is a large agriculture province.Problems of agriculture,rural areas and farmers are urgent to be solved.The development of agriculture needs the support of agricultural credits,because finance is the center of agriculture economy.However,the low comparative advantage in agriculture and pursuit of the capital interests which aggravate the conflicts of supply and demand of agricultural funds.Lacking of fund is the main factor that constrains the development of agricultural economy.In order to analyze the economic effect of agricultural credits on agricultural economy,an error correction model was set up to research the relationship between them,which based on the least square methods.Through the study of the contribution from agricultural credits to total value of agricultural out-put,the empirical evidence for developing the rural financial vigorously was provided,in order to promote the agricultura leconomic development. 展开更多
关键词 agricultural credit agricultural economy STATIONARY CO-INTEGRATION error correction model
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Real-time model correction using Kalman filter for Raman-controlled cell culture processes
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作者 Xiaoxiao Dong Zhuohong He +5 位作者 Xu Yan Dong Gao Jingyu Jiao Yan Sun Haibin Wang Haibin Qu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期251-260,共10页
Raman spectroscopy has found extensive use in monitoring and controlling cell culture processes.In this context,the prediction accuracy of Raman-based models is of paramount importance.However,models established with ... Raman spectroscopy has found extensive use in monitoring and controlling cell culture processes.In this context,the prediction accuracy of Raman-based models is of paramount importance.However,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled cultures.Thus,there is a need for effective methods to rectify these models.The objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell culture.Initially,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was compared.Subsequently,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS models.Finally,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction method.The results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled cultures.For glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled cultures.The RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),respectively.Notably,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures. 展开更多
关键词 Raman spectroscopy Model correction Algorithm Model-predictive control BIOPROCESS
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An Online Model Correction Method Based on an Inverse Problem:PartⅡ——Systematic Model Error Correction
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作者 XUE Haile SHEN Xueshun CHOU Jifan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第11期1493-1503,共11页
An online systematic error correction is presented and examined as a technique to improve the accuracy of real-time numerical weather prediction, based on the dataset of model errors (MEs) in past intervals. Given t... An online systematic error correction is presented and examined as a technique to improve the accuracy of real-time numerical weather prediction, based on the dataset of model errors (MEs) in past intervals. Given the analyses, the ME in each interval (6 h) between two analyses can be iteratively obtained by introducing an unknown tendency term into the prediction equation, shown in Part I of this two-paper series. In this part, after analyzing the 5-year (2001-2005) GRAPES- GFS (Global Forecast System of the Global and Regional Assimilation and Prediction System) error patterns and evolution, a systematic model error correction is given based on the least-squares approach by firstly using the past MEs. To test the correction, we applied the approach in GRAPES-GFS for July 2009 and January 2010. The datasets associated with the initial condition and SST used in this study were based on NCEP (National Centers for Environmental Prediction) FNL (final) data. The results indicated that the Northern Hemispheric systematically underestimated equator-to-pole geopotential gradient and westerly wind of GRAPES-GFS were largely enhanced, and the biases of temperature and wind in the tropics were strongly reduced. Therefore, the correction results in a more skillful forecast with lower mean bias and root-mean-square error and higher anomaly correlation coefficient. 展开更多
关键词 model error past data inverse problem error estimation model correction GRAPES-GFS
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Renewable energy and its impact on agricultural and economic development in the Netherlands and South Africa 被引量:1
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作者 Saul NGARAVA Alois Aldridge MUGADZA 《Regional Sustainability》 2025年第2期1-16,共16页
The use ofrenewable energyisan important way toachieve sustainable agriculturalandeconomic development.However,there are differences in accessto renewable energy between the Global North and Global South.This study ut... The use ofrenewable energyisan important way toachieve sustainable agriculturalandeconomic development.However,there are differences in accessto renewable energy between the Global North and Global South.This study utilisedan autoregressive distributed lag-error correctionmodel and thedata spanning from 1991to 2021 to comparatively analyse the dynamic relationship amongrenewable energy consumption,the value of agricultural production,gross domestic product(GDP),economic diversificationindex,urban population,the total water extraction for agricultural withdrawal,and trade balancein the Netherlands and South Africa.In the shortrun,renewable energy consumption was increased by the value of agricultural productionbut decreased by GDPin South Africa.In the longrun,renewable energy consumption and GDP increased the value of agricultural production,while the value of agricultural production also increased GDP in South Africa.However,in the Netherlands,there was no short-and long-run relationship betweenrenewable energy consumption and agricultural and economic development.The results revealedthat there was a short-and long-run relationship in South Africa.Moreover,in the Netherlands,the adjustment speed was-1.46 forrenewable energy consumption with an error correction of 0.68 a(8.22 months).In South Africa,the adjustment speedwas-1.28 forrenewable energy consumption with an error correction of 0.78 a(9.38 months).Therefore,compared to South Africa,renewable energy consumptionin the Netherlands takes less time to return to balance after a shock.Thesefindings signify different trajectories on sectoral and economic transition initiatives spurred usingrenewable energy between the Netherlands and South Africa.Policy relating to initiatives such as“agro-energy communities”in Global South countries such as South Africa should be emphasised to promote the use of renewable energy in the agricultural sector. 展开更多
关键词 Autoregressive distributed lag-error correction model(ARDL-ECM) Renewable energy consumption Agricultural production Economic development The Netherlands South Africa
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Controllingagricultural product price volatility:An empirical analysis fromCameroon
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作者 Ivette Gnitedem KEUBENG George Achu MULUH Vatis Christian KEMEZANG 《Regional Sustainability》 2025年第2期102-116,共15页
Motivated by a significant impact of price volatility on food security and economic stability inCameroon,this study aims to understand the factors influencing agricultural product price volatility(APPV)and formulateef... Motivated by a significant impact of price volatility on food security and economic stability inCameroon,this study aims to understand the factors influencing agricultural product price volatility(APPV)and formulateeffective policies for mitigating its negative impactand promoting sustainable economic growth.Specifically,this research used theautoregressive distributed lag-error correction model(ARDL-ECM)to analyse the impact of agricultural productivity,agricultural product imports,population,temperature variation,gross domestic product(GDP)per capita,and government expenditure on APPV based on the annual data from 2000 to 2021.The ARDL-ECM estimation results revealed that agricultural productivity(β=4.901),agricultural product imports(β=1.012),population(β=13.635),and GDP per capita(β=2.794)were positively related toAPPV,while temperature variation(β=-0.990)and government expenditure(β=-8.585)were negatively related toAPPVin the long term.However,temperature variation had a positive relationship with APPV in the short term.Moreover,the Granger causality test showed that there werebidirectional causality of APPV with agricultural productivityandagricultural product imports,and unidirectional causality of APPVwith population,temperature variation,GDP per capita,and government expenditure.The findings highlight the importance of public policies in stabilizing agricultural product prices by investing in agricultural research,improving access to agricultural inputs,strengthening farmer capacities,implementing climate adaptation measures,and enhancing rural infrastructure.Thesepolicies can reduce APPV,improve food security,and promote inclusive economic growth in Cameroon. 展开更多
关键词 Agricultural product price volatility(APPV) Autoregressive distributed lag-error correction model(ARDL-ECM) Food security Agricultural productivity Climate change
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Temperature compensation method for static level monitoring system and its application
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作者 Mingyu Lei Yanliang Li +8 位作者 Qing Yang Dian Xiao Jialiang Liu Fei Lv Jisheng Sui Lianchong Li Tianhui Ma Guanwen Cheng Dingzhu Liu 《Railway Sciences》 2025年第4期536-549,共14页
Purpose–This study solves the key problem that the static level monitoring is susceptible to temperature interference and affects the accuracy in slope instability/deformation monitoring.The purpose is to develop a r... Purpose–This study solves the key problem that the static level monitoring is susceptible to temperature interference and affects the accuracy in slope instability/deformation monitoring.The purpose is to develop a reliable temperature compensation method for the system,improve the accuracy of slope stability monitoring and provide support for improving the safety and safety monitoring of engineering spoil slope and other projects.Design/methodology/approach–Combined with theoretical analysis and experimental verification,the temperature compensation method is explored.The working principle of the hydrostatic leveling monitoring system is analyzed and the data processing formula,the temperature error calculation formula and the calculation formula for eliminating the error settlement value are derived.The temperature compensation method is established and verified by the field test of the engineering spoil slope which is disturbed by a debris flow.Findings–The experimental results show that this method can reduce the error of the static level monitoring system by about 40%.The field test shows that the fluctuation of slope settlement monitoring value is reduced after temperature compensation and the monitoring value is consistent with the actual situation,which has certain practicability.Originality/value–The originality of this study is to derive a theoretical formula for quantifying/eliminating temperature errors in static leveling and to establish a practical temperature compensation method.The accuracy of the system is improved,which provides a reference for slope stability monitoring under complex environment(especially railway geotechnical engineering)and promotes the development of precision monitoring technology. 展开更多
关键词 Engineering spoil Slope instability Static level Temperature error Model correction
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Cointegration analysis with structural changes between consumption and economic growth in China 被引量:3
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作者 郭建平 何建敏 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期238-241,共4页
In order to investigate the existence of a stable long-run equilibrium relationship between economic growth and consumption in China, the relationship between the gross domestic product (GDP) and consumption in Chin... In order to investigate the existence of a stable long-run equilibrium relationship between economic growth and consumption in China, the relationship between the gross domestic product (GDP) and consumption in China was investigated by the cointegration analysis method. Using the Engle-Granger (EG) test and considering the possibility of structural changes, the impact of external economic shocks on the long-run equilibrium relationship between economic growth and consumption in China was analyzed. Analysis results show that without considering structural changes, the EG test cannot detect cointegration in the series subjected to structural changes; in considering structural changes, cointegration is successfully detected by specifying the dummy variable. In addition, the error correction models were constructed in different periods. This study verifies the existence of a long-run equilibrium relationship between economic growth and consumption in China, and this relationship has significantly changed in 1989 and 1997, respectively. 展开更多
关键词 cointegration with structural changes economic growth dummy variable CONSUMPTION error correction model
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GRA BASED ANALYSIS ON FACTORS INFLUENCING CO_2 EMISSIONS IN CHINA 被引量:1
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作者 董锋 李晓晖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期152-158,共7页
How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influenti... How to achieve the objective of reducing CO2 emissions has been an academic focus in China recently. The factors influencing CO2 emissions are the vital issue to accomplish the arduous target. Firstly, three influential factors, the energy consumption, the proportion of tertiary industry in gross domestic product (GDP), and the degree of dependence on foreign trade, are carefully selected, since all of them have closer grey relation with China's COz emissions compared with others when the grey relational analysis (GRA) method is applied. The study highlights co-integration relation of these four variables using the co-integration analysis method. And then a long-term co-integration equation and a short-term error correction model of China's CO2 emissions are devel- oped. Finally, the comparison is exerted between the forecast value and the actual value of China's CO2 emissions based on error correction model. The results and the relevant statistics tests show that the pro- posed model has better explanation capability and credibility. 展开更多
关键词 grey relational analysis(GRA) CO2 emissions co-integration test error correction model
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STUDY ON THE SURFACE CRACK GROWTH BEHAVIOR IN 14MnNbq BRIDGE STEEL 被引量:3
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作者 Yanping Liu Chuanyao Chen Guoqing Li 《Acta Mechanica Solida Sinica》 SCIE EI 2010年第4期361-369,共9页
Three-dimensional crack closure correction methods are investigated in this paper.The fatigue crack growth tests of surface cracks in 14MnNbq steel for bridge plate subjected to tensile and bending loadings are system... Three-dimensional crack closure correction methods are investigated in this paper.The fatigue crack growth tests of surface cracks in 14MnNbq steel for bridge plate subjected to tensile and bending loadings are systematically conducted.The experimentally measured fatigue crack growth rates of surface cracks are compared with those of through-thickness cracks in detail.It is found that the crack growth rates of surface cracks are lower than those of through-thickness cracks.In order to correct their differences in fatigue crack growth rates, a dimensionless crack closure correction model is proposed.Although this correction model is determined only by the experimental data of surface cracks under tensile loading with a constant ratio R=0.05, it can correlate the surface crack growth rates with reasonable accuracy under tensile and bending loadings with various stress ratios ranging from 0 to 0.5.Furthermore, predictions of fatigue life and crack aspect ratio for surface cracks are discussed, and the predicted results are also compared with those obtained from other prediction approaches.Comparison results show that the proposed crack closure correction model gives better prediction of fatigue life than other models. 展开更多
关键词 crack closure correction model surface crack growth bridge steel structures fatigue life prediction
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Design of weak current measurement system and research on temperature impact 被引量:2
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作者 Chu-Xiang Zhao San-Gang Li +8 位作者 Rong-Rong Su Li Yang Ming-Zhe Liu Qing-Yue Xue Shan Liao Zhi Zhou Qing-Shan Tan Xian-Guo Tuo Yi Cheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期46-56,共11页
A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization chamber.This system incorporates a second-order low-pass filter circuit and the Kalman filterin... A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization chamber.This system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement results.Testing conducted under normal temperature conditions has demonstrated the system's high precision performance.However,it was observed that temperature variations can affect the measurement performance.Data were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this issue.The feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature correction.The research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents. 展开更多
关键词 Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model
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Cointegration Analysis on the Relation between Urbanization and Economic Growth in China 被引量:3
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作者 LIU Ai-ying YAO Li-fen LI Qing-chen 《Asian Agricultural Research》 2011年第3期133-136,共4页
This paper utilizes cointegration theory,error correcting model and Granger causality testing theory to make an empirical research on the relation between urbanization and GDP in China,and also implements a comparativ... This paper utilizes cointegration theory,error correcting model and Granger causality testing theory to make an empirical research on the relation between urbanization and GDP in China,and also implements a comparative analysis to the relation between three industries and degree of urbanization,the related coeffecient is 0.97,0.95,0.97,0.97.And the result shows a long-term balance between these two factors,and the promoting effect to tertiary industry by urbanization is more obvious.Urbanization and economic growth are the long-term balanced relations.In the long-term balance,every 1%increment of urbanization can make 4.82%increment of GDP;In short-term balance,if the balance depart from the long-term balance at the i-th term,the model will take automatic reversal adjustment with-0.06 adjusting strength at the(i+1)th term,to make it move to the long-term balance.The economic growth onto urbanization is one-way causality relationship,the primary and secondary industry onto urbanization is also one-way causality relationship.However,the tertiary industry onto urbanization is both-way causality relationship. 展开更多
关键词 Economic growth URBANIZATION Cointegration test Error correction model China
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Econometric Study of Relationship between Change of Farmland Quantity and Policy of Farmland Protection in China 被引量:3
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作者 PENG Ling LIAO Tie-jun 《Asian Agricultural Research》 2011年第3期75-78,82,共5页
According to the data from Investigation Report of Land Use Change in China,The Land Resources Communique of China and Chronicle of Statistical Data for Five Decades of New China issued from Ministry of Land Resources... According to the data from Investigation Report of Land Use Change in China,The Land Resources Communique of China and Chronicle of Statistical Data for Five Decades of New China issued from Ministry of Land Resources,we select two indices:change of farmland quantity and policy of farmland protection.According to econometric theory,by using Eviewes 5.1 software,co-integration analysis,Granger causality test,impulse response and other analysis methods,we analyze the relationship between change of farmland quantity and policy of farmland protection in China since the reform and opening-up.The results show that there is long-term balanced relationship between change of farmland quantity and policy of farmland protection,and there is a certain mechanism restricting motion of variables between the two so as to make the two deviate from each other little and step towards balance in the long run;there is unilateral causality relationship between farmland change and policy of farmland protection,namely that the farmland change is the Granger cause of policy of farmland protection,while policy of farmland protection is not the Granger cause of farmland change;impulse response and variance decomposition indicate that farmland change plays the role of promoting policy of farmland protection continuously,and the role is strengthened along with prolonged lag period;the policy of farmland protection has strong inertia,because it is impacted by the former level of itself,and the policy of farmland protection plays insignificant role in promoting farmland quantity.Consequently,the important approach of solving problem of rapid decrease of farmland is to formulate long-term strategy,strengthen theoretical research of farmland protection and reinforce degree of formulation,implementation and surveillance of farmland protection policy. 展开更多
关键词 Change of farmland quantity Policy of farmland protection Econometric analysis CO-INTEGRATION Error correction model Impulse response function Variance decomposition China
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