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Adaptive Control Based on Neural Networks for an Uncertain 2-DOF Helicopter System With Input Deadzone and Output Constraints 被引量:15
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作者 Yuncheng Ouyang Lu Dong +1 位作者 Lei Xue Changyin Sun 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期807-815,共9页
In this paper, a study of control for an uncertain2-degree of freedom(DOF) helicopter system is given. The2-DOF helicopter is subject to input deadzone and output constraints. In order to cope with system uncertaintie... In this paper, a study of control for an uncertain2-degree of freedom(DOF) helicopter system is given. The2-DOF helicopter is subject to input deadzone and output constraints. In order to cope with system uncertainties and input deadzone, the neural network technique is introduced because of its capability in approximation. In order to update the weights of the neural network, an adaptive control method is utilized to improve the system adaptability. Furthermore, the integral barrier Lyapunov function(IBLF) is adopt in control design to guarantee the condition of output constraints and boundedness of the corresponding tracking errors. The Lyapunov direct method is applied in the control design to analyze system stability and convergence. Finally, numerical simulations are conducted to prove the feasibility and effectiveness of the proposed control based on the model of Quanser's 2-DOF helicopter. 展开更多
关键词 2-degree of FREEDOM (DOF) helicopter adaptive control input DEADZONE integral barrier Lyapunov function neural networks output constraints
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Agricultural Input and Output in Jiangsu Province with Case Analysis
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作者 杜华章 《Agricultural Science & Technology》 CAS 2014年第11期2006-2010,2025,共6页
[Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation w... [Objective] The aim was to explore interrelationship between agricultural input and output in Jiangsu and the influence degrees of input factors on agricultur-al output. [Method] Quantitative analysis and evaluation were made on agricultural input and output in Jiangsu during 1990-2012 as per factor analysis and regression analysis. [Result] The result of factor analysis showed that since the 1990s, the comprehensive efficiency of agricultural input/output in Jiangsu was growing and in-put/output of agriculture, forestry, animal husbandry and fishery, crop farming, and of food production were extracted, whose scores reflect the changes of input/output ef-ficiencies in terms of agriculture, forestry, animal husbandry, fishery, crop farming and food production in the two decades. The results of regression analysis indicated that the effects of the three indices on agricultural output tended to be volatile and the influence degrees were concluded also by regression parameters. [Conclusion] The research provides theoretical references for agricultural input/output structure in Jiangsu Province. 展开更多
关键词 Agriculture input/output Factor analysis Regression analysis Jiangsu Province
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Channel capacity of multiple-input multiple-output systems with transmit and receive correlation
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作者 Wang Jun Zhu Shihua +1 位作者 Wang Lei Liu Fang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期21-26,共6页
In order to investigate the impact of channel model parameters on the channel capacity of a multipleinput multiple-output (MIMO) system, a novel method is proposed to explore the channel capacity under Rayleigh fiat... In order to investigate the impact of channel model parameters on the channel capacity of a multipleinput multiple-output (MIMO) system, a novel method is proposed to explore the channel capacity under Rayleigh fiat fading with correlated transmit and receive antennas. The optimal transmitting direction which can achieve maximum channel capacity is derived using random matrices theory. In addition, the closed-form expression for the channel capacity of MIMO systems is given by utilizing the properties of Wishart distribution when SNR is high. Computer simulation results show that the channel capacity is maximized when the antenna spacing increases to a certain point, and furthermore, the larger the scattering angle is, the more quickly the channel capacity converges to its maximum. At high SNR (〉12 dB), the estimation of capacity is close to its true wlue. And, when the same array configuration is adopted both at the transmitter and the receiver, the UCA yields higher channel capacity than ULA. 展开更多
关键词 multiple input multiple output channel capacity spatial correlation channel state information
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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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Robust Regression Analysis with LR-Type Fuzzy Input Variables and Fuzzy Output Variable
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作者 Dan Zhang Qiujun Lu 《Journal of Data Analysis and Information Processing》 2016年第2期64-80,共17页
In this paper, we propose a fuzzy linear regression model with LR-type fuzzy input variables and fuzzy output variable, the fuzzy extent of which may be different. Then we give the iterative solution of the proposed m... In this paper, we propose a fuzzy linear regression model with LR-type fuzzy input variables and fuzzy output variable, the fuzzy extent of which may be different. Then we give the iterative solution of the proposed model based on the Weighted Least Squares estimation procedure. Some properties of the estimates are proved. We also define suitable goodness of fit index and its adjusted version useful to evaluate the performances of the proposed model. Based on the Least Median Squares-Weighted Least Squares (LMS-WLS) estimation procedure, we give robust estimation steps for the proposed model. Compared with the well-known fuzzy Least Squares method, the effectiveness of our model on reducing the outliers influence is shown by using two examples. 展开更多
关键词 LR-Type Fuzzy input Variables LR-Type Fuzzy output Variable LMS-WLS Outliers Robust
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Embodied Energy and CO2 Associated with Buildings by Using Input and Output Table in Japan
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作者 Noriyoshi Yokoo Tatsuo Oka +2 位作者 Keizo Yokoyama Takao Sawachi Makoto Yamamoto 《Journal of Civil Engineering and Architecture》 2015年第2期153-164,共12页
In July 2009, the 2005 basic Japanese input/output table was publicized together with its physical transaction table. This research paper analyzed the 2005 IO (input/output) table to create building industry-related... In July 2009, the 2005 basic Japanese input/output table was publicized together with its physical transaction table. This research paper analyzed the 2005 IO (input/output) table to create building industry-related intensities and, at the same time, compared the building industry with industries at large for distribution margins and transportation. The analysis of distribution margins separately for middle and purchaser margins found that middle margins in the building industry are minor at 35% of the averages for all industries, while purchaser margins are sizable at 1.8 times, proving that it is an industry for which local production for local consumption is quite effective. CO2 emissions resulting from transportation in the building industry were calculated and concisely characterized. Although the ratio of transportation CO2 emissions to total CO2 emissions in each industry finds almost no difference between general industries and the building industry, transportation CO2 emissions per production value are two to three times heavier than those from general industries to be justified as a transportation-intensive industry. 展开更多
关键词 Embodied energy embodied CO2 input and output table.
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Robust Guaranteed Cost Output Feedback Control for Uncertain Discrete Fuzzy Systems with State and Input Delays
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作者 Xiaona Song Jinchan Wang 《控制工程期刊(中英文版)》 2013年第3期94-105,共12页
关键词 控制工程 自动控制 自动化 USTC
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An Efficient MMI SOI Splitter with Multimode Input/Output Waveguides
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作者 方青 贺月娇 +2 位作者 辛红丽 李芳 刘育梁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期276-280,共5页
A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for... A 1×8 multimode interference power splitter with multimode input/output waveguides in SOI material is designed by the beam propagation method and fabricated by the inductive coupled plasma etching technology for use in fiber optics communication systems.The fabricated device exhibits low loss and good coupling uniformity.The excess loss is lower than 0 8dB,and the uniformity is 0 45dB at the wavelength of 1550nm.Moreover,the polarization dependent loss is lower than 0 7dB at 1550nm.The device size is only 2mm×10mm. 展开更多
关键词 multimode interference power splitter SOI multimode input/output waveguides
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On the Balance Between “Input” and “Output” in College English Teaching
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作者 刘芳 《海外英语》 2016年第1期239-240,242,共3页
The current college English teaching is usually associated with two discouraging words—"time-consuming"and"inefficient", which badly demands some urgent solutions. On the basis of Krashen's In... The current college English teaching is usually associated with two discouraging words—"time-consuming"and"inefficient", which badly demands some urgent solutions. On the basis of Krashen's Input Hypothesis and Swain's Output Hypothesis, this paper elaborates the indispensable and critical roles respectively of input and output in language learning, and proposes a concept of balanced input and output in college English teaching. The paper also presents some personal suggestions as to how to bring the balance into teaching. 展开更多
关键词 COLLEGE English TEACHING input output BALANCE
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Input and Output Balance to Assist in Language Competence
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作者 马滢颖 《海外英语》 2011年第11X期109-110,共2页
Second Language Acquisition(SLA) education in China suffers from an imbalance between language input and output.Reading and listening are the dominate methods used in the classroom,while speaking and writing are used ... Second Language Acquisition(SLA) education in China suffers from an imbalance between language input and output.Reading and listening are the dominate methods used in the classroom,while speaking and writing are used far less.This paper examines the results that are caused by this imbalanced development of comprehensible output and input.Alternative solutions are examined.The results show the limitations in students' abilities that are commonly based on the current methods of teaching.The implications are that policy makers,curriculum developers and teachers should strive to balance the amount of comprehensible input and output through various means. 展开更多
关键词 SECOND LANGUAGE ACQUISITION LANGUAGE input and output
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Input and Output in Second Language Acquisition
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作者 李志远 《学周刊(下旬)》 2015年第7期7-7,共1页
Input and output are two major terminal actions in second language acquisition.For these two actions scholars have carried out a great number of researches.Among them the most famous are Krashen’s Input Hypothesis an... Input and output are two major terminal actions in second language acquisition.For these two actions scholars have carried out a great number of researches.Among them the most famous are Krashen’s Input Hypothesis and Output Hypothesis. 展开更多
关键词 英语学习 学习方法 阅读知识 阅读材料
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The Study of Strategies in College English Translation Teaching from the Perspective of Input and Output Theory
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作者 刘莹 《海外英语》 2014年第14期135-136,共2页
Research on SLA gives highlights to English translation teaching. The second language acquisition is a cognitive process of understanding and outputting the second language by making use of strategies, which contains ... Research on SLA gives highlights to English translation teaching. The second language acquisition is a cognitive process of understanding and outputting the second language by making use of strategies, which contains language input, learners' linguistic knowledge, and language output. This paper analyzes language input and output theory and then proposes that we should stress language input by practice and interaction and at the same time focus on the role of language output in college English translation teaching. 展开更多
关键词 ENGLISH TRANSLATION TEACHING LANGUAGE input langua
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Robust Output Feedback Control for a Class of Nonlinear Systems with Input Unmodeled Dynamics 被引量:4
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作者 Ming-Zhe Hou Ai-Guo Wu Guang-Ren Duan 《International Journal of Automation and computing》 EI 2008年第3期307-312,共6页
The robust global stabilization problem of a class of uncertain nonlinear systems with input unmodeled dynamics is considered using output feedback, where the uncertain nonlinear terms satisfy a far more relaxed condi... The robust global stabilization problem of a class of uncertain nonlinear systems with input unmodeled dynamics is considered using output feedback, where the uncertain nonlinear terms satisfy a far more relaxed condition than the existing triangulartype condition. Under the assumption that the input unmodeled dynamics is minimum-phase and of relative degree zero, a dynamic output compensator is explicitly constructed based on the nonseparation principle. An example illustrates the usefulness of the proposed method. 展开更多
关键词 Nonlinear systems global stabilization output feedback input unmodeled dynamics high gain
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Defected Ground Structure Multiple Input-Output Antenna For Wireless Applications
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作者 Ramya Sridhar Vijayalakshimi Patteeswaran 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2109-2122,共14页
In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Elect... In this paper,the investigation of a novel compact 2×2,2×1,and 1×1 Ultra-Wide Band(UWB)based Multiple-Input Multiple-Output(MIMO)antenna with Defected Ground Structure(DGS)is employed.The proposed Electromagnetic Radiation Structures(ERS)is composed of multiple radiating elements.These MIMO antennas are designed and analyzed with and without DGS.The feeding is introduced by a microstrip-fed line to significantly moderate the radiating structure’s overall size,which is 60×40×1 mm.The high directivity and divergence characteristics are attained by introducing the microstripfed lines perpendicular to each other.And the projected MIMO antenna structures are compared with others by using parameters like Return Loss(RL),Voltage Standing Wave Ratio(VSWR),Radiation Pattern(RP),radiation efficiency,and directivity.The same MIMO set-up is redesigned with DGS,and the resultant parameters are compared.Finally,the Multiple Input and Multiple Output Radiating Structures with and without DGS are compared for result considerations like RL,VSWR,RP,radiation efficiency,and directivity.This projected antenna displays an omnidirectional RP with moderate gain,which is highly recommended for human healthcare applications.By introducing the defected ground structure in bottom layer the lower cut-off frequencies of 2.3,4.5 and 6.0 GHz are achieved with few biological effects on radio propagation in human body communications.The proposed design covers numerous well-known wireless standards,along with dual-function DGS slots,and it can be easily integrated into Wireless Body Area Networks(WBAN)in medical applications.This WBAN links the autonomous nodes that may be situated either in the clothes,on-body or beneath the skin of a person.This system typically advances the complete human body and the inter-connected nodes through a wireless communication channel. 展开更多
关键词 MIMO-multiple input multiple output defected ground structure WBAN-wireless body area networks ULTRA-WIDEBand voltage standing wave ratio
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Comparative and Empirical Study on Vegetable Input-Output Efficiency of Suburban and Rural Areas 被引量:1
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作者 Li LI Jianmin SHI 《Asian Agricultural Research》 2015年第2期23-28 33,33,共7页
On the basis of comparative analysis on the vegetable input-output efficiency of suburban and rural areas in 2011- 2012,this paper made co-integration test,impulse response and variance decomposition for the vegetable... On the basis of comparative analysis on the vegetable input-output efficiency of suburban and rural areas in 2011- 2012,this paper made co-integration test,impulse response and variance decomposition for the vegetable input-output relationship of suburban areas in 1998-2012. Comparative analysis indicated that the vegetable input-output benefit of suburban area declines,while that of rural area rises; empirical analysis indicated that there is a long-term stable relationship between labor cost of vegetable planting and vegetable income and between material cost of vegetable planting and vegetable income,but the vegetable income itself has certain lag effect,followed by material cost,and the labor cost has minimum influence. Finally,it came up with recommendations for improving suburban vegetable input-output relationship,including improving vegetable input security mechanism,improving farmers' quality and innovation ability,and increasing technological input. 展开更多
关键词 VEGETABLE input VEGETABLE output SUBURBAN area Rur
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Fundamental Theories of Second Language Acquisition: The Input Hypothesis, the Output hypothesis, and the Interaction Hypothesis 被引量:1
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作者 ZHAO Congmin 《Sino-US English Teaching》 2021年第7期192-195,共4页
In the field of applied linguistics,several hypotheses have been proposed for second language acquisition:the Input Hypothesis,the Output hypothesis,and the Interaction Hypothesis.They address the fundamental componen... In the field of applied linguistics,several hypotheses have been proposed for second language acquisition:the Input Hypothesis,the Output hypothesis,and the Interaction Hypothesis.They address the fundamental components of successful second language acquisition respectively.This paper introduces these hypotheses and constructs a comprehensive picture based on them。 展开更多
关键词 input output INTERACTION
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Tool Condition Monitoring Based on Nonlinear Output Frequency Response Functions and Multivariate Control Chart
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作者 Yufei Gui Ziqiang Lang +1 位作者 Zepeng Liu Hatim Laalej 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第4期243-251,共9页
Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significa... Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significant damage to workpieces and reduce manufacturing costs.Recently,an innovative TCM approach based on sensor data modelling and model frequency analysis has been proposed.Different from traditional signal feature-based monitoring,the data from sensors are utilized to build a dynamic process model.Then,the nonlinear output frequency response functions,a concept which extends the linear system frequency response function to the nonlinear case,over the frequency range of the tooth passing frequency of the machining process are extracted to reveal tool health conditions.In order to extend the novel sensor data modelling and model frequency analysis to unsupervised condition monitoring of cutting tools,in the present study,a multivariate control chart is proposed for TCM based on the frequency domain properties of machining processes derived from the innovative sensor data modelling and model frequency analysis.The feature dimension is reduced by principal component analysis first.Then the moving average strategy is exploited to generate monitoring variables and overcome the effects of noises.The milling experiments of titanium alloys are conducted to verify the effectiveness of the proposed approach in detecting excessive flank wear of solid carbide end mills.The results demonstrate the advantages of the new approach over conventional TCM techniques and its potential in industrial applications. 展开更多
关键词 intelligent manufacturing multivariate control chart Nonlinear Autoregressive with eXogenous input modelling Nonlinear output Frequency Response Functions tool condition monitoring
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Output regulation of singular linear systems with input saturation by composite nonlinear feedback control
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作者 LIN Xiaoyan CHEN Lingmei +1 位作者 LIN Dongyun LAN Weiyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期834-843,共10页
Composite nonlinear feedback (CNF) control techniquefor tracking control problems is extended to the output regulationproblem of singular linear systems with input saturation. A statefeedback CNF control law and an ... Composite nonlinear feedback (CNF) control techniquefor tracking control problems is extended to the output regulationproblem of singular linear systems with input saturation. A statefeedback CNF control law and an output feedback CNF controllaw are constructed respectively for the output regulation problemof singular linear systems with input saturation. It is shown thatthe output regulation problem by CNF control is solvable underthe same solvability conditions of the output regulation problemby linear control. However, with the virtue of the CNF control, thetransient performance of the closed-loop system can be improvedby carefully designing the linear part and the nonlinear part of theCNF control law. The design procedure and the improvement ofthe transient performance of the closed-loop system are illustratedwith a numerical simulation. 展开更多
关键词 singular linear system input saturation output regula-tion composite nonlinear feedback
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Shannon information capacity of time reversal wideband multiple-input multiple-output system based on correlated statistical channels 被引量:1
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作者 杨瑜 王秉中 丁帅 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期5-10,共6页
Utilizing channel reciprocity, time reversal(TR) technique increases the signal-to-noise ratio(SNR) at the receiver with very low transmitter complexity in complex multipath environment. Present research works abo... Utilizing channel reciprocity, time reversal(TR) technique increases the signal-to-noise ratio(SNR) at the receiver with very low transmitter complexity in complex multipath environment. Present research works about TR multiple-input multiple-output(MIMO) communication all focus on the system implementation and network building. The aim of this work is to analyze the influence of antenna coupling on the capacity of wideband TR MIMO system, which is a realistic question in designing a practical communication system. It turns out that antenna coupling stabilizes the capacity in a small variation range with statistical wideband channel response. Meanwhile, antenna coupling only causes a slight detriment to the channel capacity in a wideband TR MIMO system. Comparatively, uncorrelated stochastic channels without coupling exhibit a wider range of random capacity distribution which greatly depends on the statistical channel. The conclusions drawn from information difference entropy theory provide a guideline for designing better high-performance wideband TR MIMO communication systems. 展开更多
关键词 information entropy time reversal wideband multiple-input multiple-output(MIMO) system antenna mutual coupling
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SOME RESULTS ON CONTINUOUS TYPE CONDITIONAL INPUT-OUTPUT EQUATION-FIXED POINT AND SURJECTIVITY METHODS 被引量:1
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作者 刘颖范 陈晓红 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第3期358-366,共9页
Based on the classical(matrix type)input-output analysis,a type of nonlinear (continuous type) conditional Leontief model,input-output equation were introduced,as well as three corresponding questions,namely,solvabili... Based on the classical(matrix type)input-output analysis,a type of nonlinear (continuous type) conditional Leontief model,input-output equation were introduced,as well as three corresponding questions,namely,solvability,continuity and surjectivity,and some fixed point and surjectivity methods in nonlinear analysis were used to deal with these questions. As a result,the main theorems are obtained,which provide some sufficient criterions to solve above questions described by the boundary properties of the enterprises consuming operator. 展开更多
关键词 input-output equation SOLVABILITY continuity SURJECTIVITY fixed point upper semi-continuous upper hemi-continuous nonlinear analysis
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