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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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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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Input-parallel output-parallel configuration of boost half bridge DC-DC converter with control strategy
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作者 SOOMRO Amir Mahmood KHAHRO Shahnawaz Farhan +2 位作者 KHASKHELI Murad Ali 廖晓钟 FARHAN Manzoor 《Journal of Beijing Institute of Technology》 EI CAS 2014年第1期47-52,共6页
The concept of connecting two boost half bridge DC-DC converter modules in input-paral- lel output-parallel configuration is presented. The input-parallel-output-parallel (IPOP) converter consists of multiple boost ... The concept of connecting two boost half bridge DC-DC converter modules in input-paral- lel output-parallel configuration is presented. The input-parallel-output-parallel (IPOP) converter consists of multiple boost half bridge (BHB) DC-DC converter modules which are connected in par- allel at the input and output side. This kind of converter is an attractive solution for high power ap- plications. The correlation between input current sharing (ICS) and output current sharing (OCS) of the IPOP converter basic modules is described. Two loop control strategies, consisting of input cur- rent loop and output voltage loop, have been developed to achieve equal ICS and OCS in this present work. The control strategy for the IPOP configuration of boost haft bridge DC-DC converter has been verified for different load conditions (half load and full load), The IPOP system proposed here is comprising of two modules but it can be extended to three or more. The performance of the pro- posed system along with the control strategy is verified by simulation in MATLAB using Simpower tool. Finally the satisfactory simulation results are obtained. 展开更多
关键词 boost half bridge BHB input current sharing ICS input-parallel output-parallel(IPOP) output current sharing (OCS)
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Sustainable Intensification and Large-scale Operation of Cultivated Land Use at the Farmers’ Scale:A Case Study of Shandong Province,China
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作者 LI Li LYU Xiao +2 位作者 ZHANG Anlu NIU Shandong PENG Wenlong 《Chinese Geographical Science》 SCIE CSCD 2024年第1期149-167,共19页
Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges ... Sustainable intensification of cultivated land use(SICLU) and large-scale operations(LSO) are widely acknowledged strategies for enhancing agricultural performance.However,the existing literature has faced challenges in precisely defining SICLU and constructing comprehensive indicators,which has hindered the exploration of factors influencing LSO within the SICLU framework.To address this gap,we integrated self-efficacy theory into the design of an index framework for evaluating SICLU.We subsequently employed econometric models to analyze the significant factors that impact LSO.Our findings reveal that SICLU can be divided into four key dimensions:intensive management,efficient output,resource conservation,and ecological environment optimization.Furthermore,it is crucial to incorporate belief-based cognitive factors into the index system,as farmers’ understanding of fertilizer and pesticide application significantly influences their willingness to engage in LSO.Moreover,we identify grain market turnover as the most influential factor in promoting LSO,with single-factor contribution rates reaching 70.9% for cultivated land transfer willingness and 62.5% for the total planting areas.Interestingly,unlike irrigation and agricultural machinery inputs,increased labor inputs correspond to larger planting areas for farmers.This trend may be attributed to reduced labor availability because of rural labor migration,whereas the reduction in irrigation and agricultural input is contingent on innovations in production practices and the transfer of cultivated land management rights.Importantly,SICLU dynamically influences LSO,with each index related to SICLU having an optimal range that fosters LSO.These insights offer valuable guidance for policymakers,emphasizing farmers as their central focus,with the adjustment of input and output factors as a means to achieve LSO as the ultimate goal.In conclusion,we propose research avenues for further enriching the SICLU framework to ensure that it aligns with the specific characteristics of regional agricultural development. 展开更多
关键词 sustainable intensification of cultivated land use(SICLU) SELF-EFFICACY status quo bias input and output Boosted Regression Tree willingness to transfer cultivated land cultivated land planting areas Shandong China
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The Input-output Status and Farmers’Willingness to Choose Ecological Operation of Hickory
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作者 LIU Qiang LI Shi-yong WU Wei-guang 《Asian Agricultural Research》 2012年第11期30-34,共5页
This study takes Lin'an City which early carries out the experiment of ecological operation of hickory as the study site.On the basis of the input-output data on hickory and farmers' land,we analyze the input-... This study takes Lin'an City which early carries out the experiment of ecological operation of hickory as the study site.On the basis of the input-output data on hickory and farmers' land,we analyze the input-output status of hickory land which practises ecological operation,the operators' willingness to accept ecological operation and the influencing factors.The results show that in the short term,ecological operation of hickory will have a certain negative impact on the economic benefits;within the experimental area,the degree of operators' willingness to accept ecological operation of hickory is high,and the operators have a clear understanding of long-term comprehensive benefits which may be brought by ecological operation;the ecological experiment and demonstration of hickory have achieved certain results;family income level,characteristics of householders,education and training,and so on,are the main factors that affect the operators' willingness to choose ecological operation.Finally,for how to further improve the promotion efficiency of ecological operation of hickory,we put forth some constructive recommendations. 展开更多
关键词 input and output WILLINGNESS to CHOOSE ECOLOGICAL
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Input and output efficiency of urban agglomerations in China using DEA multi-stage model
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作者 LI Qiu-ying 《Ecological Economy》 2019年第2期95-100,共6页
In this study, we apply the data envelopment analysis(DEA) model to quantitatively measure the input and output efficiency of 19 urban agglomerations in China from 2011 to 2016. The results show that the input and out... In this study, we apply the data envelopment analysis(DEA) model to quantitatively measure the input and output efficiency of 19 urban agglomerations in China from 2011 to 2016. The results show that the input and output efficiency of urban agglomerations is relatively not high, only a small number of that reach the optimal DEA efficiency. It is clearly revealed that there are the regions from the east that presents the better performance, followed by regions from the central and the west. The peer counts show that Zhusanjiao is taken into account 12 times which shows the importance here of the Zhusanjiao model.Considering the values for radial movements and the slack movements, respective urban agglomeration has their improving orientation towards the capital slack, the labor slack or the land slack. It offers a scientific decision-making of for healthy urbanization and high quality development. 展开更多
关键词 input and output EFFICIENCY urban agglomerations MULTI-STAGE DEA
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APPLICATION OF FRF ESTIMATOR BASED ON ERRORS-IN-VARIABLES MODEL IN MULTI-INPUT MULTI-OUTPUT VIBRATION CONTROL SYSTEM
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作者 GUAN Guangfeng CONG Dacheng HAN Junwei LI Hongren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第4期101-105,共5页
The FRF estimator based on the errors-in-variables (EV) model of multi-input multi-output (MIMO) system is presented to reduce the bias error of FRF HI estimator. The FRF HI estimator is influenced by the noises i... The FRF estimator based on the errors-in-variables (EV) model of multi-input multi-output (MIMO) system is presented to reduce the bias error of FRF HI estimator. The FRF HI estimator is influenced by the noises in the inputs of the system and generates an under-estimation of the true FRF. The FRF estimator based on the EV model takes into account the errors in both the inputs and outputs of the system and would lead to more accurate FRF estimation. The FRF estimator based on the EV model is applied to the waveform replication on the 6-DOF (degree-of-freedom) hydraulic vibration table. The result shows that it is favorable to improve the control precision of the MIMO vibration control system. 展开更多
关键词 Multi-input multi-output(MIMO) system Errors-in-variables(EV) model 6-DOF hydraulic vibration table Waveform replication
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基于Input-Output模型的新疆水资源合理配置研究 被引量:2
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作者 刘爽 李莉 荣伟 《江西农业学报》 CAS 2018年第5期101-105,109,共6页
根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量... 根据2007和2012年新疆统计年鉴和投入产出表等相关资料,利用Input-output模型和水资源结构偏差系数对国民经济各产业的用水效率、用水效益指数等进行了分析。研究表明:2012年新疆各产业水资源利用效率和效益显著提高,但农业用水消耗量远高于其产出效益,第三产业和生态环境产业的水资源消耗呈现递减趋势。此外,工业和建筑业的水资源配置较为合理。最后,为促进新疆水资源优化配置提出了相应的对策建议。 展开更多
关键词 水资源 合理配置 input-output模型 新疆
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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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语言学习过程中的“Input”和“Output”类课程特点分析
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作者 田凤俊 《教育教学论坛》 2010年第11期165-166,共2页
"Input"和"Output"作为语言学习和运用的两个主要方式,历来备受语言研究者和学习者的关注。因此,有关它们的理论著述和观点也颇多。但主要是如何就二者能很好的在中国英语外语环境中得以有效地应用和实践,如在高校... "Input"和"Output"作为语言学习和运用的两个主要方式,历来备受语言研究者和学习者的关注。因此,有关它们的理论著述和观点也颇多。但主要是如何就二者能很好的在中国英语外语环境中得以有效地应用和实践,如在高校英语专业课程群中得以很好的实施则显得非常必要和实用。将所有英语外语课程按照"Input"和"Output"进行分类并按照课程建模的方式进行课程教学和人才培养是本文讨论的主要任务。 展开更多
关键词 input”和“output 语言学习和习得 课程建模 英语外语教学
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From Input to Output-Exploring the Role of Intake in English Learning
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作者 黄志红 《山东师范大学外国语学院学报(基础英语教育)》 2007年第4期7-17,54,共12页
This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not t... This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not take place directly from input to output.In each sqecific part of L2 acquisition process,intake plays various important roles such as filtering,facilitating in comprehensible input and processing in pushed output.In the Chinese foreign language teaching context,it is also found that L2 acquisition is an arduous task for learners to extract information from the input,utilize it in forming a grammar and produce target language forms accurately and fluently.It is the same with L2 teachers who need to play their roles of a controller,a corrector,an organizer and a prompter in the learning process. 展开更多
关键词 英语教学 第二语言习得 中学 输入 输出 消化吸收
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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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A Pilot Study on Task Frequency Effects of Input-Output Cycles on EFL Learners’Oral Proficiency
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作者 王玉山 《中国校外教育》 2012年第9期40-41,共2页
This paper gives a report of the findings of a pilot study on task frequency effects of input-output cycles on EFL learners'oral proficiency.The results showed that the experimental group made greater progress in ... This paper gives a report of the findings of a pilot study on task frequency effects of input-output cycles on EFL learners'oral proficiency.The results showed that the experimental group made greater progress in complexity and accuracy than control groups.We may come to the conclusion that circular input-out benefits learners most.The study may give some insights for foreign language teachers to give second language learners appropriate tasks in listening and speaking classes. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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Input和Output理论在高职高专英语口语教学中的应用*
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作者 孙淑梅 《贵州商业高等专科学校学报》 2012年第2期76-78,共3页
影响高职高专学生英语口语训练的因素有很多。从Input和Output(输入和输出)理论的角度,分析影响口语发展障碍的成因,并从教、学双重角度考虑,提出相应的教学对策。
关键词 输入输出 英语口语 障碍 教学对策
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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:11
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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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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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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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Sensitivity of Chinese Industrial Wastewater Discharge Reduction to Direct Input Coefficients in an Input-output Context 被引量:3
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作者 TANG Zhipeng GONG Peiping +1 位作者 LIU Weidong LI Jiangsu 《Chinese Geographical Science》 SCIE CSCD 2015年第1期85-97,共13页
Industrial wastewater discharge in China is increasing with the country′s economic development and it is worthy of concern. The discharge is primarily relevant to the direct discharge coefficient of each sector of th... Industrial wastewater discharge in China is increasing with the country′s economic development and it is worthy of concern. The discharge is primarily relevant to the direct discharge coefficient of each sector of the economy, its direct input coefficient and the final demand in input-output models. In this study, we calculated the sensitivity of the reduction in the Chinese industrial wastewater discharge using the direct input coefficients based on the theory of error-transmission in an input-output framework. Using input-output models, we calculated the direct and total industrial wastewater discharge coefficients. Analysis of 2007 input-output data of 30 sectors of the Chinese economy and of 30 provincial regions of China indicates that by lowering their direct input coefficients, the manufacturers of textiles, paper and paper products, chemical products, smelting and metal pressing, telecommunication equipment, computers and other electronic equipment will significantly reduce their amounts of industrial wastewater discharge. By lowering intra-provincial direct input coefficients to industrial sectors themselves of Jiangsu, Shandong and Zhejiang, there will be a significant reduction in industrial wastewater discharge for the country as a whole. Investment in production technology and improvement in organizational efficiency in these sectors and in these provinces can help lessen the direct input coefficients, thereby effectively achieving a reduction in industrial wastewater discharge in China via industrial restructuring. 展开更多
关键词 工业废水排放 中国经济 直接输入 输入输出 敏感性 上下文 投入产出模型 废水排放系数
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