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Global qualitative analysis of new Monod type chemostat model with delayed growth response and pulsed input in polluted environment 被引量:1
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作者 孟新柱 赵秋兰 陈兰荪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第1期75-87,共13页
In this paper, we consider a new Monod type chemostat model with time delay and impulsive input concentration of the nutrient in a polluted environment. Using the discrete dynamical system determined by the stroboscop... In this paper, we consider a new Monod type chemostat model with time delay and impulsive input concentration of the nutrient in a polluted environment. Using the discrete dynamical system determined by the stroboscopic map, we obtain a "microorganism-extinction" periodic solution. Further, we establish the sufficient conditions for the global attractivity of the microorganism-extinction periodic solution. Using new computational techniques for impulsive and delayed differential equation, we prove that the system is permanent under appropriate conditions. Our results show that time delay is "profitless". 展开更多
关键词 PERMANENCE impulsive input chemostat model time delay for growth response EXTINCTION
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Construction of Two-Region Input-output Model——A Case Study of Henan Province 被引量:1
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作者 SHANG Yong Department of Statistics, Henan University of Economics and Law, Zhengzhou 450002, China 《Asian Agricultural Research》 2012年第1期9-12,共4页
On the basis of input-output table of Henan Province and China in 2007, this paper advances a simple method of constructing two-region input-output model using MRIO model, to research the economic link between the ind... On the basis of input-output table of Henan Province and China in 2007, this paper advances a simple method of constructing two-region input-output model using MRIO model, to research the economic link between the industries of Henan Province and the industries of other regions. I summarize the characteristics of this method based on this as follows: when researching inter-regional economic link, the multi-region or two-region input-output model has prominent superiority, and we can conduct preliminary estimation on the multi-region input-output model using location quotient approach. 展开更多
关键词 input-OUTPUT model LOCATION QUOTIENT MRIO model In
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Multimodel-based flight control system reconfiguration control in the presence of input constraints 被引量:2
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作者 Yuying GUO Bin JIANG Yufei XU 《控制理论与应用(英文版)》 EI 2010年第4期418-424,共7页
In this paper,an active fault accommodate strategy is proposed for the plant in the presence of actuator fault and input constraints,which is a combination of a direct adaptive control algorithm with multiple model sw... In this paper,an active fault accommodate strategy is proposed for the plant in the presence of actuator fault and input constraints,which is a combination of a direct adaptive control algorithm with multiple model switching.The μ-modification is introduced in the model reference architecture to construct the adaptive controller.The proof of stability is based on the candidate Lyapunov function,while appropriate switching of multiple models guarantees asymptotic tracking of the system states and the boundedness of all signals.Simulation results illustrate the efficiency of the proposed method. 展开更多
关键词 Actuator fault Adaptive control reconfiguration Multiple model input constraint RBF neural network
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The Influences of Energy Price Variation on the Prices of Other Industries: A Study Based on Input-Output Price Model 被引量:2
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作者 Aiwen Zhao Ruilin Li 《Open Journal of Energy Efficiency》 2019年第2期35-51,共17页
Energy has laid material foundation for human society during its development. Meanwhile, any change of price in the energy industry may influence social production and people’s life at all levels via an input-output ... Energy has laid material foundation for human society during its development. Meanwhile, any change of price in the energy industry may influence social production and people’s life at all levels via an input-output mechanism under which the change related to energy is surely transmitted to other industries. The price change thus incurred in all industries may adversely affect the realization of macroeconomic objective-maintaining prices at a stable level. It is, therefore, needed to conduct an empirical research related to the impact of price change in energy industry on that in other industries. According to the data coming from “China’s 2015 Input-Output Extension Table (42 Departments)” and four hypothetical basis, this article focuses on four energy sectors and analyzes how deeply the price change of them, by use of input-output model, affects that of other industrial products under five conditions where each of their price rises by 10% individually or simultaneously, and why such an influence occurs. The results show that the price rising of the energies in question leads to an upward growth in the prices of other industrial products, especially when their prices go up simultaneously. Besides, the price increase in the four energy sectors doesn’t influence other industries in an accumulation form but actually leads to a rollback in some of other industries. It is recommended to adopt diversified pricing strategies for different energy products, thus maximizing the value of each specific energy, and meanwhile achieving the goals of energy consumption reduction and price equilibrium. 展开更多
关键词 Energy PRICE VARIATION input-OUTPUT PRICE model
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Environmental input-output model and its analysis with a focus on the solid waste management sectors
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作者 Zeng, Guang-Ming Yuan, Xing-Zhong +3 位作者 Zhang, Pan-Yue Guo, Huai-Cheng Huang, Gordon Guo-He Hemelaar, L. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第2期53-58,共6页
An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy developme... An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy development. Some details about how to use the EIOM was discussed. The EIOM was applied to the Changsha City in China. The example results indicate that much useful information related to the environment and the regional economy development can be gained from the solution of the EIOM. Thus, the EIOM can be used as a useful tool for the sustainable development planning including the solid waste management sectors. 展开更多
关键词 environmental input\|output model analysis of economy and environment solid waste management
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T-Y TUBE MODEL OF HUMAN ASCENDINGAORTIC INPUT IMPEDANCE
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作者 吴望一 戴国豪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第12期0-0,0-0+0-0+0-0+0-0+0,共11页
This paper proposed a T- Y tube model to simulate foe input impedance of arterial system. It improves and extends the asymmetric T-tube model which was firstproposed by O' Rourke[1] and developed laier by Liu et a... This paper proposed a T- Y tube model to simulate foe input impedance of arterial system. It improves and extends the asymmetric T-tube model which was firstproposed by O' Rourke[1] and developed laier by Liu et al.[2]. Based on foe asymmetricT-tube model. a T-Y tube model was proposed by adding branching tubes whichrepresem the iliac arteries.All the tubes are considered to be uniform,viscoelasticlongitudinally tethered cylindrical tubes.The upper tube terminates with a windkesselmodel, while the terminal arterioles of the lowr tube are expressed as a resistance.After proper eraluation of the parameters.the impedance of the arterial system iscalculated under normal physiological and hypertensive condition.The model canpredict impedance in good agreement with the experimentally obtained data no matterin normal physiological condition or in pathological condition In comparison with theasymmeric T-tube model,T- Y tube model is closer to anatomy structure of the human arlerial system and at the sametime much simpler than the extremely complex multiplebranching tube model Therefore it will be a valuable model in studying the influencesof various parameters on aorta impedance and ventricular-vascular coupling. 展开更多
关键词 T-Y tube model ascending aortic input impedance Multiple-branching tube model
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New model reference adaptive control with input constraints
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作者 武文斌 耿庆波 +1 位作者 费庆 胡琼 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期405-412,共8页
A new scheme of adaptive control is proposed for a class of linear time-invariant( LTI) dynamical systems,especially in aerospace,with matched parametric uncertainties and input constraints. Based on a typical and c... A new scheme of adaptive control is proposed for a class of linear time-invariant( LTI) dynamical systems,especially in aerospace,with matched parametric uncertainties and input constraints. Based on a typical and conventional direct model reference adaptive control scheme,various modifications have been employed to achieve the goal. "C omposite model reference adaptive control"of higher performance is seam-lessly combined with "positive μ-mod",which consequently results in a smooth tracking trajectory despite of the input constraints. In addition,bounded-gain forgetting is utilized to facilitate faster convergence of parameter estimates. The stability of the closed-loop systemcan be guaranteed by using Lyapunov theory.The merits and effectiveness of the proposed method are illustrated by a numerical example of the longitudinal dynamical systems of a fixed-wing airplane. 展开更多
关键词 model reference adaptive control input constraints flight control
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Regional Agricultural Input-Output Model and Countermeasure for Production and Income Increase of Farmers in Southern Xinjiang,China
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作者 Jiang Qing-song Zhang Xing-ji 《Asian Agricultural Research》 2010年第6期29-33,共5页
Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage ... Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage of water resources,tremendous pressure on ecological balance,insignificant economic and social benefits of agricultural production in southern Xinjiang,agriculture remaining a weak industry,agricultural economy as the economic subject of southern Xinjiang,and backward economic development of southern Xinjiang.Taking the Aksu area as an example,according to the input and output data in the years 2002-2007,input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis.DPS software is used in the process of solving the model.Then,Eviews software is adopted to revise and test the model in order to analyze and evaluate the economic significance of the results obtained,and to make additional explanations of the relevant model.Since the agricultural economic output is seriously restricted in southern Xinjiang at present,the following countermeasures are put forward,such as adjusting the structure of agricultural land,improving the utilization ratio of land,increasing agricultural input,realizing agricultural modernization,rationally utilizing water resources,maintaining eco-environmental balance,enhancing the awareness of agricultural insurance,minimizing the risk and loss,taking the road of industrialization of characteristic agricultural products,and realizing the transfer of surplus labor force. 展开更多
关键词 Regional agriculture input-output model Production and income increase Principal component analysis Econometric model China
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Nonlinear Systems Identification via an Input-Output Model Based on a Feedforward Neural Network
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作者 O. L. Shuai South China University of Technology, Gungzhou, 510641, P.R. China S. C. Zhou S. K. Tso T. T. Wong T.P. Leung The Hong Kong Polytechnic University, HungHom, Kowloon, HK 《International Journal of Plant Engineering and Management》 1997年第4期45-50,共6页
This paper develops a feedforward neural network based input output model for a general unknown nonlinear dynamic system identification when only the inputs and outputs are accessible observations. In the developed m... This paper develops a feedforward neural network based input output model for a general unknown nonlinear dynamic system identification when only the inputs and outputs are accessible observations. In the developed model, the size of the input space is directly related to the system order. By monitoring the identification error characteristic curve, we are able to determine the system order and subsequently an appropriate network structure for systems identification. Simulation results are promising and show that generic nonlinear systems can be identified, different cases of the same system can also be discriminated by our model. 展开更多
关键词 nonlinear dynamic systems identification neural networks based input Output model identification error characteristic curve
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Application of Linear Model Predictive Control and Input-Output Linearization to Constrained Control of 3D Cable Robots
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作者 Ali Ghasemi 《Modern Mechanical Engineering》 2011年第2期69-76,共8页
Cable robots are structurally the same as parallel robots but with the basic difference that cables can only pull the platform and cannot push it. This feature makes control of cable robots a lot more challenging comp... Cable robots are structurally the same as parallel robots but with the basic difference that cables can only pull the platform and cannot push it. This feature makes control of cable robots a lot more challenging compared to parallel robots. This paper introduces a controller for cable robots under force constraint. The controller is based on input-output linearization and linear model predictive control. Performance of input-output linearizing (IOL) controllers suffers due to constraints on input and output variables. This problem is successfully tackled by augmenting IOL controllers with linear model predictive controller (LMPC). The effecttiveness of the proposed method is illustrated by numerical simulation. 展开更多
关键词 CABLE ROBOTS input-OUTPUT LINEARIZATION Linear model PREDICTIVE Control
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GREY DISPLACEMENT INPUT-OUTPUT MODELS OF MINERAL PROCESSING-METALLURGY SYSTEM
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作者 Han Xuli Li Songren(Department of Mineral Engineering, Central South University of Technology, Changsha, 410083) 《中国有色金属学会会刊:英文版》 CSCD 1995年第1期11-14,共4页
GREYDISPLACEMENTINPUT-OUTPUTMODELSOFMINERALPROCESSING-METALLURGYSYSTEMHan;XuliLi;Songren(DepartmentofMineral... GREYDISPLACEMENTINPUT-OUTPUTMODELSOFMINERALPROCESSING-METALLURGYSYSTEMHan;XuliLi;Songren(DepartmentofMineralEngineering,Centr... 展开更多
关键词 MINERAL processing-metallurgy SYSTEM input-OUTPUT GREY theory economic model
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数字经济与实体经济融合是否提升了企业创新能力——基于正反向融合度的非线性检验 被引量:4
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作者 吕延方 赵琳慧 王冬 《厦门大学学报(哲学社会科学版)》 北大核心 2024年第2期107-120,共14页
促进数字经济与实体经济深度融合,依托数字技术与设备实现核心领域突破性创新,是高质量发展的关键。编制我国非竞争投入产出表,从供需双层面和广义狭义双范畴,可构建并测算我国数字经济与实体经济正、反向融合度,探究数字经济与实体经... 促进数字经济与实体经济深度融合,依托数字技术与设备实现核心领域突破性创新,是高质量发展的关键。编制我国非竞争投入产出表,从供需双层面和广义狭义双范畴,可构建并测算我国数字经济与实体经济正、反向融合度,探究数字经济与实体经济融合对实体企业创新影响及内在机制。研究发现,融合度对实体创新的影响存在非线性效应,正向融合度整体提升实体企业创新质量和效率,这与技术吸收能力强化相关;反向融合度处于合理区间时才能拉动创新增长,否则将因成本效应和适应性不足降低实体工业创新质量和效率。 展开更多
关键词 数字经济 非竞争投入产出模型 融合度 创新能力 非线性效应
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A Generalization of the Input-Output Pollution Control Model and Product Selection
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作者 Aniekan Ebiefung 《Applied Mathematics》 2013年第2期360-362,共3页
The input-output pollution control model given in [1] is generalized. The generalization makes it easier for the model to handle many problem instances. A linear program is used to solve the new model. An example is g... The input-output pollution control model given in [1] is generalized. The generalization makes it easier for the model to handle many problem instances. A linear program is used to solve the new model. An example is given to show that the new model can handle classes of problems that the original model cannot handle. 展开更多
关键词 input-OUTPUT POLLUTION ENVIRONMENT TECHNOLOGY Leontief PRODUCTION model
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中国经济国内国际双循环测度——基于三种GDP分解的比较分析 被引量:1
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作者 李晓 刘宝琦 《南开经济研究》 北大核心 2024年第1期3-19,共17页
依据单一GDP分解方法测度双循环存在多种缺陷。本文从增加值流转视角比较分析三种GDP分解方法下的直接指标,构建一种以间接指标测度双循环的新框架,并将其应用于中国经济双循环格局演化分析和国际比较分析。研究表明,1995—2018年,中国... 依据单一GDP分解方法测度双循环存在多种缺陷。本文从增加值流转视角比较分析三种GDP分解方法下的直接指标,构建一种以间接指标测度双循环的新框架,并将其应用于中国经济双循环格局演化分析和国际比较分析。研究表明,1995—2018年,中国制造业国内循环比例呈逐渐下降又大幅回调过程,本质上是对中国双循环格局“大内循环倾向”特征的回归,并不代表“国内大循环为主”经济发展格局已经形成;不同经济体双循环格局具有明显异质性,即具有“大内循环倾向”或“小内循环倾向”。这种异质性相对稳定,经济体双循环格局的演变进程主要表现为国内外市场关联和上下游产业关联两种结构力量作用下,在双循环类型空间的局部调整。从构建以国内大循环为主体,国内国际双循环相互促进的新发展格局出发,反映国内国际循环比例的直接指标不是合适的政策目标,中国应根据不同行业特点,根据间接指标所反映的双循环格局类型和结构特征,聚焦产业链整合和治理挖掘增长潜力。 展开更多
关键词 双循环 全球价值链 增加值 投入产出模型
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“双碳”背景下中国制造业绿色出口竞争力研究
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作者 姜鸿 吴婷 张艺影 《生态经济》 北大核心 2024年第2期52-60,共9页
在“双碳”背景下,提升中国制造业绿色出口竞争力对发展绿色贸易具有重要意义。论文引入碳排放权交易价格,运用多区域投入产出模型,将传统的单位劳动成本改进为单位绿色隐含劳动成本,将出口增加值国际市场份额改进为绿色出口增加值国际... 在“双碳”背景下,提升中国制造业绿色出口竞争力对发展绿色贸易具有重要意义。论文引入碳排放权交易价格,运用多区域投入产出模型,将传统的单位劳动成本改进为单位绿色隐含劳动成本,将出口增加值国际市场份额改进为绿色出口增加值国际市场份额,进而构建绿色出口竞争力指数,测算并比较中国十大制造行业绿色出口竞争力。研究发现,2005—2019年中国大部分制造行业单位绿色隐含劳动成本和绿色出口竞争力指数均在上升,其中单位绿色隐含劳动成本上升最多的是金属制品业,从2005年的0.409上升到2019年的0.780,绿色出口竞争力指数上升最多的是非金属矿物制品业,从0.243上升到1.069。回归结果表明,研发投入和行业规模对中国制造业绿色出口竞争力有显著正向影响。针对以上结论,在“双碳”目标下,论文提出提高劳动生产率、培育可持续竞争优势、加大技术研发投入等政策建议。 展开更多
关键词 单位绿色隐含劳动成本 绿色出口竞争力指数 多区域投入产出模型
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中国出口贸易隐含碳的趋势预测及结构转移研究
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作者 胡剑波 麦骏南 《气候变化研究进展》 CSCD 北大核心 2024年第1期62-74,共13页
基于特征选择的Lasso方法分别确定影响中国出口贸易隐含碳排放(CO_(2))总量和强度的核心指标,并由此构建BO-BiLSTM模型对总量变动和强度演进的趋势展开预测,同时采用Markov链进一步探讨中国出口贸易隐含碳排放的结构转移现象。结果表明:... 基于特征选择的Lasso方法分别确定影响中国出口贸易隐含碳排放(CO_(2))总量和强度的核心指标,并由此构建BO-BiLSTM模型对总量变动和强度演进的趋势展开预测,同时采用Markov链进一步探讨中国出口贸易隐含碳排放的结构转移现象。结果表明:(1) 2021—2035年间中国出口贸易隐含碳排放总量呈现阶梯式减少的趋向,预计2030年达到1.98 Gt,在2035年降为1.83 Gt,出口贸易规模扩大和国际经贸形势改善是关键影响因素。(2) 2021—2035年间中国出口贸易隐含碳排放强度保持稳中有降的态势,预计2030年减至0.91 t/万元,相较于2005年减少67%,出口贸易结构变迁和环境规制强度提高是重要驱动因素。(3) 2021—2035年间中国出口贸易隐含碳排放结构仍偏重知识密集型制造业,其存在较大减排潜力,而资本密集型服务业和资本密集型制造业具有减排周期较长的特点。 展开更多
关键词 出口贸易隐含碳 投入产出模型 机器学习预测
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中国产业部门隐含碳生产率的驱动因素分解——基于LMDI-PDA模型的实证分析
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作者 胡剑波 吴驰宸 《经济问题》 北大核心 2024年第8期43-51,共9页
提升隐含碳生产率是产业部门碳减排的关键。基于2002—2020投入产出数据与能源碳排放数据建立隐含碳生产率指标,利用LMDI-PDA综合分解法,系统梳理各效应、各细分产业部门对产业部门整体隐含碳生产率变动的影响。研究结论为:直接排放率... 提升隐含碳生产率是产业部门碳减排的关键。基于2002—2020投入产出数据与能源碳排放数据建立隐含碳生产率指标,利用LMDI-PDA综合分解法,系统梳理各效应、各细分产业部门对产业部门整体隐含碳生产率变动的影响。研究结论为:直接排放率效应对28个产业部门中的大部分产业部门的隐含碳生产率提升起到阻碍作用,排放能效效应以及能源资本替代效应则主要起积极作用;隐含碳生产率效应普遍推动三次产业隐含碳生产率上升,排放结构效应则阻碍第二产业与第三产业隐含碳生产率的增长,负向效应分别为-0.0166万元/吨、-0.0190万元/吨;对产业部门整体隐含碳生产率增长贡献最大的两个产业部门是其他服务业和建筑业。研究结论为加速推进产业低碳变革提供了理论与数据支撑。 展开更多
关键词 非竞争型投入产出模型 隐含碳生产率 产业部门
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“十强”产业发展对山东经济增长的贡献研究
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作者 崔俊富 刘洋 武慧兰 《边疆经济与文化》 2024年第1期27-34,共8页
经济增长与产业发展密不可分,实现山东新旧动能转换的关键就在于推动产业发展。山东确定了重点发展“十强”产业,在做大、做强、做优“十强”产业上实现新突破。借助投入产出技术研究发现,“十强”产业在宏观、中观、微观等三个层面对... 经济增长与产业发展密不可分,实现山东新旧动能转换的关键就在于推动产业发展。山东确定了重点发展“十强”产业,在做大、做强、做优“十强”产业上实现新突破。借助投入产出技术研究发现,“十强”产业在宏观、中观、微观等三个层面对山东经济增长都发挥了重要的作用。未来应采取优化营商环境、加强科技创新、培育壮大市场主体、扩大对外开放等措施推动“十强”产业发展。 展开更多
关键词 “十强”产业 山东 经济增长 投入产出模型
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国内价值链贸易核算:基于增加值分解与地位测度研究综述
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作者 廉晓梅 吴金华 《统计与决策》 北大核心 2024年第13期130-135,共6页
文章在梳理国内价值链内涵界定和基本模型构建的基础上,从增加值分解与地位测度视角系统比较了国内价值链贸易核算框架演进过程,并探讨了未来的发展方向。首先,明晰了国内价值链属权和属地概念的内涵边界,并基于属地概念运用中国区域间... 文章在梳理国内价值链内涵界定和基本模型构建的基础上,从增加值分解与地位测度视角系统比较了国内价值链贸易核算框架演进过程,并探讨了未来的发展方向。首先,明晰了国内价值链属权和属地概念的内涵边界,并基于属地概念运用中国区域间投入产出表建立了一个基础理论模型框架;其次,通过对封闭经济条件下内需驱动的增加值分解范式和开放经济条件下涵盖国内和国外成分的总流出分解、省域部门层面出口增加值分解、“双循环”战略背景下国内价值链嵌入全球价值链模型框架的分析,揭示了不同模型的适用范围、关联性与拓展方向,研究发现,国内价值链贸易核算模型的构建为测度国内价值链分工位置与地位奠定了基础,两者有效衔接,深化了对国内垂直专业化分工的认识,拓展了分工贸易研究领域;最后,从经济理论、价值链条和模型数据角度给出未来可进一步研究的方向。 展开更多
关键词 国内价值链 双重价值链 投入产出模型 增加值分解 分工地位
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基于DEA模型的安康市农业投入产出效率评价
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作者 张盉儆 张亚晴 《农业工程》 2024年第4期153-157,共5页
为了解安康市现代农业发展效率状况,选取2009—2020年安康市污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数4个农业投入指标,以及农业总产值和农业人均生产值2个农业产出指标,采用数据包络分析(data envelopment ... 为了解安康市现代农业发展效率状况,选取2009—2020年安康市污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数4个农业投入指标,以及农业总产值和农业人均生产值2个农业产出指标,采用数据包络分析(data envelopment analysis,DEA)模型中的BCC模型进行效率分析。结果表明,安康市农业投入产出效率只有2020年的DEA模型是有效的,但从2009年开始,综合效率总体呈现上升趋势;从投入冗余率与产出不足率可以看出,安康市农业总产值基本不存在产出不足的现象,除2020年外,其余各年份在污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数的投入在不同程度都存在冗余,投入结构不合理造成DEA模型无效。 展开更多
关键词 农业 DEA模型 投入产出 效率评价 安康市
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