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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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Structural changes and volatility correlation in nonferrous metal market 被引量:1
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作者 吴丹 胡振华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2784-2792,共9页
The GARCH and DCC-GARCH models are used to study the volatility aggregation and dynamic relevance of China’s three kinds of nonferrous metals (copper, aluminum and zinc) pricesincorporating structural changes. The ... The GARCH and DCC-GARCH models are used to study the volatility aggregation and dynamic relevance of China’s three kinds of nonferrous metals (copper, aluminum and zinc) pricesincorporating structural changes. The results show that copper, aluminum and zinc returns have many structure breaks points, and nonferrous metals have the greatvolatilityrisk during financial crisis. From the resultsof GARCH with and without structural changes,it isfoundthat the volatility clustering of single nonferrous metal is overvalued when ignoring the structural mutation, and the return of aluminum isthe most overvalued, indicating that aluminum market is more susceptible to external shock.Furthermore,it is also foundthatdynamic volatility correlation exists in the three prices of nonferrous metals, and the structural changes have no significant effect on the volatility correlation of thethree nonferrous metals. 展开更多
关键词 copper ZINC ALUMINUM nonferrous metals price structural changes DCC-GARCH model volatilitydynamic correlation
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Effects of mechanical activation on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation tailings 被引量:3
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作者 Ermolovich E.A. Ermolovich O.V. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期1043-1049,共7页
The effects of mechanical activation in a planetary mill on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation railings generated by wet magnetic separa... The effects of mechanical activation in a planetary mill on the structural changes and microstructural characteristics of the components of ferruginous quartzite beneficiation railings generated by wet magnetic separation process were studied using X-ray and laser diffraction methods. The results revealed the relationship between variations in the mean particle size of activated powders and the milling time. The crystallite size, microstrain, lattice parameters and unit cell volumes were determined for different milling times in powder samples of quartz, hematite, dolomite, and magnetite from the beneficiation tailings. The main trends in the variation of the crystallite size of quartz, hematite, dolomite, and magnetite as a function mean particle size of powder samples were revealed. Changes in the particle shape as a function of the activation time was also investigated. 展开更多
关键词 Ferruginous quartzite beneficiation tailings Mechanical activation Crystallites Planetary mill Microstructure structural changes
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Industrial Structural Changes in Hong Kong,China under One Country,Two Systems Framework
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作者 Simon Xiaobin ZHAO Carola B RAMóN-BERJANO 《Chinese Geographical Science》 SCIE CSCD 2012年第3期302-318,共17页
Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Adminis... Hong Kong has undergone substantial economic transformations and developed into a sophisticated busi- ness and financial center in the Asia-Pacific region, since the return of sovereignty to China as a Special Administrative Region under the One Country Two Systems (OCTS) in 1997. This paper discusses and analyzes the industrial struc- tural changes of Hong Kong in recent decades as well as its future challenges and opportunities, The data and finding reveal that even though Hong Kong will face fierce competition from the Mainland's cities as the rise of China, the important role as a bridge between China and the rest of the world wilt brace Hong Kong itself under the OCTS for developing into a service hub for business and trade in the Asia-Pacific region. 展开更多
关键词 economic transformation Hong Kong industrial structural changes One Country Two Systems
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Studies on Structural Changes of Collagen in Silicosis
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作者 LIYU-RUI HUXUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第4期302-306,共5页
In order to provide scientific information on the prevention and treatment of silicosis,studies about changes of silicotic collagen in lungs were carried out. In this paper, we present experiments about the structural... In order to provide scientific information on the prevention and treatment of silicosis,studies about changes of silicotic collagen in lungs were carried out. In this paper, we present experiments about the structural changes of collagen in silicotic lungs of rats and patients. These included electron microscopy, circular dichroism and infrared spectroscopy studies of collagen fibers. The results indicated that fibers of silicotic collagen were shorter in length, smaller in diameter and decreased in α-helix content. The -Si-O-R- group and -OH group were found increased and -C-C- backbone shortened. The increase of -Si-O-R-group indicated that silica formed linking bridges between collagens which may be the cause of progressive enlargement of nodules 展开更多
关键词 SI In Studies on structural changes of Collagen in Silicosis
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Study of Local Structural Changes on Air Cooling at the End of Rotor Windings for Variable Speed Pumped Storage Generator-Motor
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作者 Yanliang Qiu Bin Xiong +1 位作者 Zhe Hou Lin Luo 《Energy Engineering》 EI 2022年第6期2243-2254,共12页
The shrink fit retaining ring is currently the easiest to install and the most widely used end fixed for structure AC excitation variable speed generator-motor rotor end windings.However,the current research on the ef... The shrink fit retaining ring is currently the easiest to install and the most widely used end fixed for structure AC excitation variable speed generator-motor rotor end windings.However,the current research on the effect of high strength sealing on the ventilation and heat dissipation performance of the end is not enough.In this paper,based on the actual structural parameters and periodic symmetry simplification,the three-dimensional coupled calculation model of fluid field and temperature field is established.After solving the fluid and thermal equations,the influence of the length of rotor support block,the height of rotor support block,and the number of rotor support block on the fluid flow and temperature distribution in the rotor end region of generator-motor is studied using the finite volume method.The rheological characteristics of the air in the rotor domain,such as velocity and inter-winding flow,are analyzed.The law of temperature variation with local structure in the computational domain is studied.The variation law of cooling medium performance inside the large variable speed power generator motor is revealed. 展开更多
关键词 Pumped storage plants GENERATOR-MOTOR local structural changes rotor windings end
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High Resolution Electron Microscopy Observations of Structural Changes in Iron Nitride Films Annealed in Vacuum
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作者 Shengkai GONG Huibin XU (Dept. of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第2期123-126,共4页
Iron-nitride films were prepared by reactive sputtering, and the effect of annealing treatment on the structures was investigated by means of in-situ electron microscopy and high resolution electron microscopy (HREM).... Iron-nitride films were prepared by reactive sputtering, and the effect of annealing treatment on the structures was investigated by means of in-situ electron microscopy and high resolution electron microscopy (HREM). As-deposited films were observed to be a mixed structure of a few ultrafine epsilon-Fe2-3N particles existing in the amorphous matrix. it was found that the structure-relaxation in the amorphous occurred at 473 K, and the ultrafine grains began to grow at the higher annealing temperatures. The transition of the amorphous to epsilon-Fe2-3N was almost completed at 673 K. It is considered that the formation of the ideal epsilon-Fe3N is originated from the ordering of the nitrogen atoms during the annealing in vacuum. On the other hand, gamma'-phase (Fe4N) was seen to precipitation of epsilon-phase at 723 K. Two possible modes are proposed in the precipitation of gamma'-phase, depending on the heating rate and crystallographic orientation relationships, i.e. [121](epsilon)//[001](gamma), (2(1) over bar0$)(epsilon)//(110)(gamma) and [100](epsilon)//[110](gamma), (001)(epsilon)//(111)(gamma). In addition, alpha-Fe particles were observed to form from the gamma'-phase at high temperatures. We assumed that these structural changes are due to the diffusion of nitrogen and iron atoms during the annealing, except for the case of the precipitation of the gamma'-phase as depicted above. The results obtained in this work are in a good agreement with the assumption. 展开更多
关键词 FIGURE High Resolution Electron Microscopy Observations of structural changes in Iron Nitride Films Annealed in Vacuum
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Multifractal analysis of white matter structural changes on 3D magnetic resonance imaging between normal aging and early Alzheimer's disease 被引量:1
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作者 倪黄晶 周泸萍 +3 位作者 曾彭 黄晓林 刘红星 宁新宝 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期155-161,共7页
Applications of multifractal analysis to white matter structure changes on magnetic resonance imaging(MRI) have recently received increasing attentions. Although some progresses have been made, there is no evident s... Applications of multifractal analysis to white matter structure changes on magnetic resonance imaging(MRI) have recently received increasing attentions. Although some progresses have been made, there is no evident study on applying multifractal analysis to evaluate the white matter structural changes on MRI for Alzheimer's disease(AD) research. In this paper, to explore multifractal analysis of white matter structural changes on 3D MRI volumes between normal aging and early AD, we not only extend the traditional box-counting multifractal analysis(BCMA) into the 3D case, but also propose a modified integer ratio based BCMA(IRBCMA) algorithm to compensate for the rigid division rule in BCMA. We verify multifractal characteristics in 3D white matter MRI volumes. In addition to the previously well studied multifractal feature,△α, we also demonstrated △ f as an alternative and effective multifractal feature to distinguish NC from AD subjects.Both △α and △ f are found to have strong positive correlation with the clinical MMSE scores with statistical significance.Moreover, the proposed IRBCMA can be an alternative and more accurate algorithm for 3D volume analysis. Our findings highlight the potential usefulness of multifractal analysis, which may contribute to clarify some aspects of the etiology of AD through detection of structural changes in white matter. 展开更多
关键词 MULTIFRACTAL white matter structural change magnetic resonance imaging Alzheimer's disease
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Temperature-induced anomalous structural changes of Al-12wt.%Sn-4wt.%Si melt and its influence on as-cast structure
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作者 Wang Zhiming Geng Haoran +2 位作者 Zhou Guorong Guo Zhongquan Teng Xinying 《China Foundry》 SCIE CAS 2010年第2期138-142,共5页
The temperature dependence of the viscosity of liquid Al-12wt.%Sn-4wt.%Si was studied with a hightemperature viscosity apparatus.Anomalous changes of viscosity of the melt were found at 1,103 K and 968 K in the coolin... The temperature dependence of the viscosity of liquid Al-12wt.%Sn-4wt.%Si was studied with a hightemperature viscosity apparatus.Anomalous changes of viscosity of the melt were found at 1,103 K and 968 K in the cooling process,which indicates anomalous structural changes of the melt.It is calculated that the anomalous structural change is associated with an abrupt decrease of atomic clusters'size and activation energy in the melt.According to the temperature of the anomalous structural changes,melt heat treatment process(quenching from superheat to pouring temperature) was performed on Al-12wt.%Sn-4wt.%Si melt prior to pouring,aimed to keep the small atomic clusters from higher temperature to lower pouring temperature.The results suggest that relatively small atomic clusters at the pouring temperature in the melt could generate a deep under-cooling of nucleation in the subsequent solidification process,and refine the as-cast structure.After being quenched from superheating to pouring temperature,the relatively small atomic clusters,especially the Si-Si clusters in the melt will grow to equilibrium state(relatively big atomic clusters) with holding time,resulting in the prominent coarsening of the Si morphology in the as-cast structure. 展开更多
关键词 melt heat treatment viscosity Al-Sn-Si structural change
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Structural Changes of Activated Carbon Electrodes for EDLCs in the Manufacturing Process
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作者 Bin Yang Dianbo Ruan +2 位作者 Yang Zhang Chengyang Wang Zhijun Qiao 《Transactions of Tianjin University》 EI CAS 2020年第5期391-398,共8页
Supercapacitors,or electric double-layer capacitors(EDLCs),are the new generation of energy storage devices to store electrical charges and provide high power densities and long cyclic life compared to other storage d... Supercapacitors,or electric double-layer capacitors(EDLCs),are the new generation of energy storage devices to store electrical charges and provide high power densities and long cyclic life compared to other storage devices.EDLC mainly consists of activated carbon electrodes and an electrolyte,and the performance of EDLC depends on the activated carbon electrodes.In this work,the structural changes of activated carbon electrodes are analyzed using commercial 2.7 V/9500F EDLCs in its manufacturing process.It is found that there is no significant change in morphology and crystal structure of the activated carbon,but its specific surface area(SSA)reduced greatly.The SSA of activated carbon was decreased by 23%after they were manufactured or converted into electrodes and finally retained only 40%of SSA after the capacitance test.Besides,the SSA of the positive electrodes was found to decrease critically than that of the negative electrodes.The SSA of the external positive electrodes is only 14.3%after fl oating test at 65℃. 展开更多
关键词 ELECTRODE EDLCs Pore structure Activated carbon structural change
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The multiple roles of crop structural change in productivity,nutrition and environment in China:A decomposition analysis
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作者 Xiangyang Zhang Yumei Zhang Shenggen Fan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1763-1773,共11页
China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nut... China's crop structure has undergone significant changes in the last two decades since 2000,with an increase in the share of cereals,vegetables,and fruit,squeezing out other crops.As a result,land productivity,nutrient supply,and carbon emissions have changed.How to reallocate limited farmland among crops to achieve the multiple goals of agrifood systems becomes an important issue.This study explores the sources of land productivity and nutrition supply growth and carbon emissions reduction,and identifies the multiple roles of crop structural change from 2003 to 2020 based on a decomposition analysis.The results reveal that the growth within crops is still the primary driver in land productivity and nutrition supply and the reduction in carbon emissions.However,structural change also plays various roles at different periods.From 2003 to 2010,crop structural change increased the total calorie supply but lowered land productivity and contributed at least 70%of the total growth of carbon emissions.The crop structure was relatively stable,and their effects were modest from 2010 to 2015.From 2015 to 2020,the crop structural change began to play a greater role and generate synergistic effects in improving land productivity,micronutrient supply,and reducing carbon emissions,contributing to approximately a quarter of the growth of land productivity and 30%of total carbon emissions reduction.These results suggest that strategies for crop structural change should comprehensively consider its multiple impacts,aiming to achieve co-benefits while minimizing trade-offs. 展开更多
关键词 CROP structural change land productivity NUTRITION carbon emissions
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Modified Testing for Structural Changes in Autoregressive Processes
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作者 Hao JIN Zheng TIAN Yun Feng YANG 《Journal of Mathematical Research and Exposition》 CSCD 2011年第1期79-90,共12页
In this paper, we consider the problem of detecting for structural changes in the autoregressive processes including AR(p) process. In performing a test, we employ the conventional residual CUSUM of squares test (R... In this paper, we consider the problem of detecting for structural changes in the autoregressive processes including AR(p) process. In performing a test, we employ the conventional residual CUSUM of squares test (RCUSQ) statistic. The RCUSQ test is based on the subsampling method introduced by Jach and Kokoszka [J. Methodology and Computing in Applied Probability 25(2004)]. It is shown that under regularity conditions, the asymptotic distribution of the test statistic is the function of a standard Brownian bridge. Simulation results as to AR(1) process and an example of real data analysis are provided for illustration. 展开更多
关键词 SUBSAMPLING RCUSQ test Brownian bridge structural changes
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Structural Changes in High Dimensional Factor Models
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作者 Jushan Bai Xu Han 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2016年第1期9-39,共31页
This paper provides a survey on recent developments in structural changes for high dimensional factor models. Compared with conventional low-dimensional time series, structural changes in factor models are more compli... This paper provides a survey on recent developments in structural changes for high dimensional factor models. Compared with conventional low-dimensional time series, structural changes in factor models are more complicated due to the unobservability of factors and factor loadings. The following topics are covered in this survey: the identification conditions for the structural changes in the factor loadings, different impacts of big and small breaks in factor models, tests for structural changes in the factor loadings of a specific variable, tests for structural changes in the factor loading matrix, joint tests for structural changes in the factor loadings and coefficients in factor-augmented regressions, tests for smooth changes in the factor loadings, estimation of break dates, and model selection in factor models with structural changes via the shrinkage method. 展开更多
关键词 factor models structural changes break date
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Searching Multiple Structural Changes of Chinese Stock Market via GMDH
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作者 Yixiang Tian Li Zhou 《Journal of Systems Science and Information》 2009年第3期193-200,共8页
This paper analyzes multiple structural changes by GMDH (Group Meth- ods of Data Handling), which have obvious advantages. Our method extends the model of Lumsdaine & Papell[1] (1997), and it could be applied to ... This paper analyzes multiple structural changes by GMDH (Group Meth- ods of Data Handling), which have obvious advantages. Our method extends the model of Lumsdaine & Papell[1] (1997), and it could be applied to the case of more than two structural changes. Because of simultaneously considering every structural change of the hypothesis, it is likely to be of particular relevance in practice. And it can decrease large investigation costs by MATLAB programming. What is more, we can select the criterion value of F incremental statistic to control the significance of the breaks, based on kinds of investigation intentions. And the empirical evidences on Shenzhen Composite Index are presented to illustrate the usefulness of our method. 展开更多
关键词 GMDH multiple structural changes F incremental statistic
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Oxidation Kinetics,Structural Changes and Element Migration during Oxidation Process of Vanadium-titanium Magnetite Ore 被引量:2
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作者 Feng PAN Qing-shan ZHU +1 位作者 Zhan DU Hao-yan SUN 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第11期1160-1167,共8页
The oxidation kinetics, structural changes, and elements migration during the oxidation process of the va- nadium-titanium magnetite (VTM) ore were analyzed. Kinetics analysis indicated that the oxidation process wa... The oxidation kinetics, structural changes, and elements migration during the oxidation process of the va- nadium-titanium magnetite (VTM) ore were analyzed. Kinetics analysis indicated that the oxidation process was con- trolled by diffusion control and could be divided into interface diffusion and lattice diffusion with apparent activation energy of 99.69 kJ/mol and 144.08 kJ/mol in the range of 800--1000℃, respectively. The surface structure changed with the oxidization temperature as follows: dense surface→nano sized sheets→submicron particles→molten particles. The compact structure changed into porous one because of the elements migration and enrichment. Both Fe and Ti elements migrated in the opposite direction during the oxidation process. The V etement in the raw ore stably existed in the form of V^5+ state, some vanadium migrated and occupied the tetrahedral sites of the hematite during the oxidation process. 展开更多
关键词 vanadium-titanium magnetite ore OXIDATION KINETICS structural change element migration
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Structural Changes in the Renminbi Exchange Rate Mechanism 被引量:1
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作者 Guanyu Su Junhui Qian 《China & World Economy》 SCIE 2021年第2期1-23,共23页
This paper examines structural changes in China s exchange rate mechanism.For this purpose,we propose a predictive model incorporating three factors that influence the central parity rate:a smoothing factor,a market f... This paper examines structural changes in China s exchange rate mechanism.For this purpose,we propose a predictive model incorporating three factors that influence the central parity rate:a smoothing factor,a market factor,and a basket factor.We first apply the model to analyze the effects of 12 exchange rate reforms since 2005,treating these reforms as predetermined structural breaks.Among other results,we find that the main impact of introducing a“counter-cyclical factor”is to weaken the role of the basket factor.We estimate structural breaks in data,assuming that the number and dates of breaks are unknown,and we find that,although the majority of estimated breaks occur within the neighborhood of exchange rate reforms,there are breaks due to other external shocks such as the escalation of the China-US trade conflict in May 2019.It is suggested that our model may be used to guide future currency reforms in China. 展开更多
关键词 central parity rate exchange rate reform RMB structural change
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On the agricultural growth and structural changes in Suzhou Wuxi Changzhou region
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作者 XIE Jie ZENG Zungu Department of Urban and Resources Studies, Nanjing University, Nanjing 210093, CHINA XIONG Ning Department of Geography, Jiangsu Normal College, Nanjing 210013, CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第4期76-83,共8页
s—Suzhou Wuxi Changzhou Region (Su Xi Chang) is a famous prosperous agricultural region in China. Since the early 1980s agriculture in Su Xi Chang has got constant developed, but its growth rate is lower than t... s—Suzhou Wuxi Changzhou Region (Su Xi Chang) is a famous prosperous agricultural region in China. Since the early 1980s agriculture in Su Xi Chang has got constant developed, but its growth rate is lower than the provincial average level of Jiangsu, and its structure has not changed much. Therefore it lost many in the position of agricultural areal division of labour within Jiangsu Province. The authors of this paper suggest that Su Xi Chang agriculture should perform multiple social, economic and ecological functions with the suburban and export oriented farming as the main development direction. It is also necessary to improve management and organization structure for enhancing Su Xi Chang agricultural vitality. 展开更多
关键词 agricultural growth structure change growth pattern Suzhou Wuxi Changzhou.
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The Impacts of the Growth of the Three Industries and Industrial Price Structural Changes on China’s Economic Growth between 1952 and 2019
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作者 Dihai Wang 《China Finance and Economic Review》 2021年第4期3-27,共25页
This paper focuses on the impacts and effects of China’s growth of the three industries and price structural change on the real GDP growth rate.First of all,it presents a new accounting method for decomposing growth ... This paper focuses on the impacts and effects of China’s growth of the three industries and price structural change on the real GDP growth rate.First of all,it presents a new accounting method for decomposing growth rates on the basis of existing accounting method for decomposing growth rates.By using this method,we can identify the impacts and effects of structural changes on the growth rate.The paper uses a new decomposition method to recalculate China’s industry-based real GDP growth rates between 1952 and 2019,focuses on the driving effect of growth of the three industries on the real GDP growth,and the impacts of price structural change on GDP growth rate and the contributin of the growth of the three industries on GDP growth rate.By analysis,this paper shows that between 1952 and 2019 China’s economic growth was mainly driven by the secondary industry,which had contributed to the economic growth by over 50%,the role of the tertiary industry in driving economic growth rose,but that of the secondary industry declined over the time;in the short run,the overall effect of the price structural changes of the three industries has a little impact on the economic growth,but the price change of each industry has strong effects,and the price structural change has signifi cantly changed the effect of the growth of the three industries on the real economic growth;in the long term,the price structural change plays a relatively big hindering effect on economic growth due to the Baumol’s cost disease. 展开更多
关键词 economic growth three industries price structural change decomposition of economic growth rate
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Microwave Drying of Scots Pine Lumber:Structure Changes,Its Effect on Liquid Permeability
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作者 Sheng He Weiqi Leng +4 位作者 Yuhe Chen Hongchen Li Jingpeng Li Zaixing Wu Zizhang Xiao 《Journal of Renewable Materials》 SCIE EI 2023年第1期321-331,共11页
Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron m... Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron microscope(TEM)examination.Pore parameters before and after MW treatment were detected by mercury intrusion porosimetry(MIP)method,and the effect of structure changes on liquid permeability were analyzed.As stereoscope microscope,SEM and TEM examination results showed,macro and micro checks mainly developed at intercellcular of tracheids,intercellular of ray parenchyma and tracheid,while these checks extend main along the radial-longitudinal plane.Pit border destruction,aspirated pits’orus translocation and micro-checks in tracheid cell wall were also observed.MIP test shown that pore volume and pore area increased as macro and micro checks generated to form new cavities.Microstructure changes would increase the quantity of pores or enlarge the pore diameter.Liquid flow pathways increased as macro and micro checks generated,aspirated pits reopened to form new pathways;liquid flow efficiency improved as porosity,pore volume and pore diameter increased which facilitated the liquid flow. 展开更多
关键词 Microwave drying structure change pore structure liquid permeability Scots pine lumber
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Simulation and Analysis of Land System Structure Changes in Huang-Huai-Hai Plain Area 被引量:6
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作者 邓祥征 战金艳 +2 位作者 苏红波 姜群鸥 迟百余 《Agricultural Science & Technology》 CAS 2007年第3期45-52,共8页
The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the d... The dynamic changes of land system in Huang - Huai - Hai Plain between 1988 and 2000 were researched in this paper. Spatial dominance econometric model was estabilished on 1 km cell to quantificafionally analyze the driving-force for the dynamic change mechanism of land system, such as natural, social and economic factors. The future dynamic changes of land system in Huang - Huai - Hai Plain on each 1 km cell during 2000 to 2020 were stimulated by combining the dynamic changes of land system on each 1 km cell with different situations. The research indicated that the dynamic changes of land system structure changed mainly from the cultivated areas to building areas and industrial areas, and forest areas increased during this period. Although the revolutions of land system structure were different during 2000 to 2020 with the different referrence standard, ecological protection and economic development, the primary dynamic changes of land system structure were that the increase of building land areas with the decline cuhivaled land areas and the increase of woodlands. 展开更多
关键词 LAND Land system Land system structure Land system structure change Land use Dynamic simulation Huang- Huai -Hai Plain
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