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An extended input-output table for environmental and resources accounting
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作者 Feng Wu Jinyan Zhan +1 位作者 Chenchen Shi Chunhong Zhao 《Chinese Journal of Population,Resources and Environment》 2014年第1期33-41,共9页
Environmentally Extended Input-Output(EEIO)tables have become a powerful element in supporting information-based environmental and economic policies.National-and provincial-level 10 tables are currently published by t... Environmentally Extended Input-Output(EEIO)tables have become a powerful element in supporting information-based environmental and economic policies.National-and provincial-level 10 tables are currently published by the National Bureau of Statistics of the People's Republic of China according to well-defined conventions.However,county-level 10tables are not provided as a rule by official statistics organizations.This paper conducts an overview of compiling EEIO tables for environmental and resources accounting at the county level and then answers several questions:First,what kind of data should be prepared for the compilation of county-level EEIO tables?Second,how can we set up comprehensive EEIO tables at the county level?Third,regarding the survey methods and the indirect modeling,which one should be chosen to build EEIO tables at the county level?Finally,what policy questions could such a table answer?EEIO tables at the county level can be used to predict the economic impacts of environmental policies and to perform trend and scenario analysis. 展开更多
关键词 county-level input-output table ACCOUNTING influence coefficients
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TECHNIQUES OF CONSTRUCTING REGIONAL INPUT-OUTPUT TABLES: ACHIEVEMENTS
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作者 金玉献 Christine MLeigh 《Chinese Geographical Science》 SCIE CSCD 1992年第4期47-66,共20页
The development of any analytical method should have to experience at least four stages: its initial status, growth, mature and declining. However, although the regional input-output analysis has been widely applied f... The development of any analytical method should have to experience at least four stages: its initial status, growth, mature and declining. However, although the regional input-output analysis has been widely applied for more than forty years, it is still one of the most important approach in regional economic analysis and forecast at present in the world. This is due to the never ended modifications and its great potentials. In this paper, we review the historical development of the regional input-output analysis. 展开更多
关键词 input-output REGIONAL research REGIONAL input-output MODELS
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The Research of Mutual Economic Relations of the World Countries on the Basis of Input-Output Table
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作者 Yadulla Hasanli Jeyhun Abbasov 《Economics World》 2014年第4期215-222,共8页
"Input-output" table which was designed for solution of mutual relation (impact) problem is a widely applied tool in the world for conducting economic analysis and forecasting. One of the most important problem of... "Input-output" table which was designed for solution of mutual relation (impact) problem is a widely applied tool in the world for conducting economic analysis and forecasting. One of the most important problem of today's world is to prevent financial-economic crises in several countries of the world and especially in Eurozone countries where it is still ongoing. Input-output balance tables were prepared by modifying input-output table based on relevant economic indicators of the biggest countries of economy in the world as well as simulations were conducted by designing several balance models (mutual impact of GDP and change in general output of countries, mutual impact of added value and prices, mutual impact of GDP and work places). Level of coverage of relevant indicators used in analysis on the countries of the world were tested on the basis of statistic methods and assessed. It was identified that, level of confidence of the coverage in designed model on world economy is higher than 95%. These models enable to analyze and forecast possible changes in world economy caused by changes which took place in economic conjecture of other big countries of the world, especially in USA, Japan, Germany, and China. It should be noted that, model's system was automatized in EXCEL system with the purpose of simplifying simulations and conducting analysis and increasing efficiency on the usage of models. 展开更多
关键词 input-output GDP final product general output workforce added value PRICES
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Intensity Calculation Using Input-Output Table and Case Study Regarding Embodied Energy/CO2 in Japan
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作者 Makoto Yamamoto Keizo Yokoyama +2 位作者 Noriyoshi Yokoo Tatsuo Oka Takao Sawachi 《Journal of Civil Engineering and Architecture》 2015年第3期321-330,共10页
The objective of this research is to quantify the EEC (embodied energy/CO2) of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building's life-cycle, such as constr... The objective of this research is to quantify the EEC (embodied energy/CO2) of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building's life-cycle, such as construction (including manufacture of materials and equipment), renewal (including repair work) and demolition. Energy and CO2 emission intensities in terms of 401 sectors were calculated, using the 2005 I-O (input-output) table in Japan. According to our case study conducted from the construction phase to demolition, the EC (embodied CO2) of an office building used for 60 years is 12,044 t-CO2 and 1,093 kg-CO2/m^2 in total. CO2 equivalent emissions (CO2e) by Freon gases, contained in building materials, equipment and devices, were also calculated. As the results, CO2e by insulators was 2% of the building's EC and CO2e by refrigerants was 9%-12% of the building's EC. It is important to keep reducing emissions of Freon gases contained in refrigerators. 展开更多
关键词 I-O table intensity of energy and CO2 embodied energy/CO〉
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Importance measurement of domestic and foreign firms in Chinese provinces:A multi-regional input-output table based on the double extension of geographic regions and firm ownerships
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作者 Fangke Liu Lizhi Xing 《Journal of Data and Information Science》 2025年第4期13-43,共31页
Purpose:The study evaluates the relative roles of Domestic-Funded Enterprises(DFEs)and Foreign-Funded Enterprises(FFEs)across Chinese provinces.It further examines how industrial structures differ by ownership at both... Purpose:The study evaluates the relative roles of Domestic-Funded Enterprises(DFEs)and Foreign-Funded Enterprises(FFEs)across Chinese provinces.It further examines how industrial structures differ by ownership at both regional and national scales.Drawing on these findings,the analysis traces the geographic shift of FFEs and offers evidence-based guidance for shaping foreign investment policy.Design/methodology/approach:This study uses Inter-Country Input-Output(ICIO)and Inter-Region Input-Output(IRIO)tables to build two extended datasets:Ownership-Extended Inter-Country Input-Output(OE-ICIO)and Ownership-Extended Multi-Region Input-Output(OE-IRIO)tables.These are then combined to construct the Regionally-Ownership Dually-Extended Multi-Regional Input-Output(RODE-MRIO)table and Global Domestic and Foreign Enterprises Network(GDFEN)model to explore the industrial relocation trends of FFEs in China.Findings:The results indicate that:(1)From 2010 to 2019,FFEs in China showed an overall decline in influence,profitability,and network robustness.(2)Eastern and developed regions saw a clear retreat of FFEs,with a shift toward domestic control.Central regions and more developed regions played a transitional role.Moreover,western and less developed regions remained stable but still relied on low-end and resource-based activities.(3)FFEs’influence has been gradually shifting towards less-developed central and western provinces due to rising labor costs and stricter environmental regulations.Research limitations:First,only general policy recommendations are proposed,without exploring the design of specific policy instruments.Second,the significant impact of recent trade measures on the behavior of FFEs has not been considered.Third,further research is needed to deepen the analysis by comparing regional ownership dynamics in China with those in other major economies.Practical implications:This research provides valuable insights for policymakers aiming to enhance regional economic development and improve China’s position within Global Value Chains(GVCs).Originality/value:The originality of this paper lies in its development of a new model that combines geographic,sectoral,and ownership dimensions.This model allows for a clearer analysis of the roles of foreign and DFEs in China’s regional economy.It offers insights into industrial transfer trends within global value chains and provides a framework for analyzing and forecasting future shifts. 展开更多
关键词 Multiregional input-output tables Global Value Chain Reconfiguration Industry Shift Development Heterogeneity
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Development and Reproduction of Sweet Potato Whitefly Bemisia tabaci (Homoptera;Aleyroididae) on Four Vegetable Crops in Southern Sierra Leone
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作者 Peter Dennis Musa Sahr Tortor +1 位作者 Jusu Momoh Lahai Osman Bashir Salam Jalloh 《Advances in Entomology》 2025年第1期182-199,共18页
Bemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of veget... Bemisia tabaci is a polyphagous herbivore that feeds on a wide range of horticultural and ornamental crops cultivated under diverse ecological zones. In Sierra Leone, B. tabaci is found to infest a wide range of vegetable crops by directly feeding on phloem sap thereby inducing physiological disorders, and also serve as a vector to gemini viruses. Invariably the destructive feeding of B. tabaci affects the productivity and aesthetic values of vegetables and other horticultural crops and hence is considered a serious economic pest. A bioassay experiment was carried out by rearing B. tabaci populations on four vegetable crops under controlled laboratory conditions to determine its life table and demographic parameters. Results showed that the intrinsic rate of growth which measures the population size and growth pattern was highest for populations reared on tomato crops with the following values: rm 0.145 female female−1 day−1, the gross reproduction rate (Ro), and finite growth rate λ were highest for population reared on tomato, correspondingly the development period from egg-adult emergence was shortest with a value of 26 d. Conversely, the computed demographical parameters rm, λ and Ro for the population reared on sweet pepper were 0.106 female female−1 day−1 respectively, with a corresponding development period egg-adult emergence as 36d. The computed biological parameters for okra and garden egg varied with intermediary values between tomato and pepper host materials. The survivorship rates were quite significant for the smaller instars (Instars 1-III) with over 80% surviving to pre-pupa and pupa stage for the populations reared for all the test materials. High mortality was noticed for the pre-pupa and pupa stages as their survival rates were significantly low compared to the high survival rates of the smaller instars. Less than 50% of pupae failed to emerge to adults except for populations reared on tomato test materials where 52% emerged to adults. The study indicated tomato as the most suitable host among the four vegetable crops. Although life table and demographic parameters are invaluable information for forecasting pest populations and help in designing pest management efforts, further investigations such as the economic threshold and economic injury levels of B. tabaci population are requisite decision tools for sound pest management decisions of B. tabaci on these vegetable crops. The information obtained from this investigation would be quite relevant for extension service and pest management practitioners where mixed vegetable farming is a common practice. 展开更多
关键词 Bemisia tabaci Life table Demographic Parameters Host Plants Biological Attributes Population Dynamics
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"The Youth Tablee Tennis Programme——Photo Exhibition of Zhou Enlaiand the Bandung Conference&China-ASEAN(Indonesia)Youth Table Tennis Training Camp"Opened in Jakarta
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《International Understanding》 2025年第2期61-62,共2页
On April 19th,"the Youth Table Tennis Programme—Photo Exhibition of Zhou Enlai and the Bandung Conference&China-ASEAN(Indonesia)Youth Table Tennis Training Camp"opened in Jakarta,Indonesia.The event was... On April 19th,"the Youth Table Tennis Programme—Photo Exhibition of Zhou Enlai and the Bandung Conference&China-ASEAN(Indonesia)Youth Table Tennis Training Camp"opened in Jakarta,Indonesia.The event was guided by the Chinese Embassy in Indonesia and co-organised by the ASEAN-China Centre(ACC),the Memorial to Zhou Enlai and Deng Yingchao,the China Friendship Foundation for Peace and Development,the Beijing One Heart Sphere Charity Foundation,and the Enlai Foundation. 展开更多
关键词 youth table tennis programme zhou enlai jakarta photo exhibition table tennis china asean enlai foundation youth table tennis training camp
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Table manners
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作者 Maria Chiu 《空中英语教室(初级版.大家说英语)》 2025年第10期21-24,52,53,56,共7页
Table manners are important in manycultures.Inmost countries,youwait untileveryone has food before eating.Youalso don't put your elbows on the table.It's not polite to eat too fast.And youshouldn't talk wi... Table manners are important in manycultures.Inmost countries,youwait untileveryone has food before eating.Youalso don't put your elbows on the table.It's not polite to eat too fast.And youshouldn't talk with food in yourmouth orchew with your mouth open. 展开更多
关键词 eating etiquette cultural norms table manners
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Effects of weak interlayers on seismic performance of bedding slopes based on shaking table tests
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作者 Hailong Yang Xiangjun Pei +2 位作者 Shenghua Cui Zhihao He Jin Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6517-6529,共13页
Weak interlayers play a crucial role in the seismic performance of bedding slopes;however,the effects of structural surface development within these layers remain underexplored.This study presents two scaled models of... Weak interlayers play a crucial role in the seismic performance of bedding slopes;however,the effects of structural surface development within these layers remain underexplored.This study presents two scaled models of bedding slopes,each with different weak interlayers:one with a homogeneous weak layer and another with discontinuous interfaces.Shaking table tests were conducted to compare their seismic performance.The results show that the peak ground acceleration(PGA)values above the weak interlayer in model A were significantly higher than those in model B,with the differences increasing as the input wave amplitude increased.The peak earth pressure(PEP)values at the tensile failure boundary at the rear edge of model A were also higher,whereas those within the weak layer at the toe of model A were lower than those in model B.Deformation analysis revealed that the maximum principal strain in model A initially appeared at the upper part of the tensile failure boundary,while the maximum shear strain was concentrated near the rear edge within the weak layer.In contrast,model B exhibited the opposite strain distribution.These findings provide insight into the impact of weak interlayers on the dynamic response and deformation of bedding slopes,highlighting the importance of considering this factor in seismic landslide investigations and failure mode predictions. 展开更多
关键词 Dynamic response Seismic deformation Bedding slopes Weak interlayer Shaking table test
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Large-scale shaking table test on unlined tunnel in fault zone under threedimensional earthquake
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作者 ZHANG Xiaoyu TAO Zhigang +1 位作者 YANG Xiaojie ZHANG Ruixue 《Journal of Mountain Science》 2025年第1期296-311,共16页
A fault is a geological structure characterized by significant displacement of rock masses along a fault plane within the Earth's crust.The Yunnan Tabaiyi Tunnel intersects multiple fault zones,making tunnel const... A fault is a geological structure characterized by significant displacement of rock masses along a fault plane within the Earth's crust.The Yunnan Tabaiyi Tunnel intersects multiple fault zones,making tunnel construction in fault-prone areas particularly vulnerable to the effects of fault activity due to the complexities of the surrounding geological environment.To investigate the dynamic response characteristics of tunnel structures under varying surrounding rock conditions,a three-dimensional large-scale shaking table physical model test was conducted.This study also aimed to explore the damage mechanisms associated with the Tabaiyi Tunnel under seismic loading.The results demonstrate that poor quality surrounding rock enhances the seismic response of the tunnel.This effect is primarily attributed to the distribution characteristics of acceleration,dynamic strain,and dynamic soil pressure.A comparison between unidirectional and multi-directional(including vertical)seismic motions reveals that vertical seismic motion has a more significant impact on specific tunnel locations.Specifically,the maximum tensile stress is observed at the arch shoulder,with values ranging from 60 to 100 k Pa.Moreover,NPR(Non-Prestressed Reinforced)anchor cables exhibit a substantial constant resistance effect under low-amplitude seismic waves.However,when the input earthquake amplitude reaches 0.8g,local sliding occurs at the arch shoulder region of the NPR anchor cable.These findings underscore the importance of focusing on seismic mitigation measures in fault zones and reinforcing critical areas,such as the arch shoulders,in practical engineering applications. 展开更多
关键词 Fault tunnel Shaking table test Dynamic response Three-directional earthquake Damage mechanism
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Seismic stability analysis of sandy slope with anti-slide pipe piles through shaking table tests and finite element
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作者 SALEH ASHEGHABADI Mohsen XU Jianmin +2 位作者 JIA Yuyue LIU Junwei WANG Yulin 《Journal of Mountain Science》 2025年第10期3744-3768,共25页
Seismic-induced landslides critically threaten infrastructure and human safety,especially in sandy slopes where conventional stabilization methods often fail under dynamic loading.This study evaluates circular open-en... Seismic-induced landslides critically threaten infrastructure and human safety,especially in sandy slopes where conventional stabilization methods often fail under dynamic loading.This study evaluates circular open-ended anti-slide pipe piles embedded in a two-layer sandy slope with differing geotechnical properties.Ten physical models,including five freefield and five pile-reinforced slopes,were tested on a shaking table.Key seismic responses—acceleration,soil displacement,and bending moments—were monitored using accelerometers,strain gauges,and Digital Image Correlation(DIC).Complementary numerical simulations using Abaqus with a Mohr–Coulomb model validated experimental results.Soil displacement in free-field models under 0.25g shaking was about 3.5 times greater than in reinforced slopes.Bending moments increased with seismic intensity,peaking at depths around five times the pile diameter.Limitations including simplified two-layer soil representation,idealized seismic inputs,and boundary effects inherent to laboratory models restrict direct field application but enable controlled analysis.By combining physical experiments with numerical modeling,the study provides a robust and validated framework for seismic slope stabilization.This integrated approach enhances understanding of soil–pile interaction under seismic loads and offers targeted insights for developing safer and more reliable geotechnical design strategies in earthquake-prone areas. 展开更多
关键词 Anti-slide piles Shaking table tests Sloping lands Soil-pile models Free-field models
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Seismic response analysis of buried pipelines with varying stiffness by shaking table tests
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作者 Chen Hongyu Cui Jie +3 位作者 Li Yadong Ouyang Zhiyong Huang Xiangyun Shan Yi 《Earthquake Engineering and Engineering Vibration》 2025年第2期583-594,共12页
The relative stiffness between underground structures and surrounding soil may significantly influence the dynamic response of such structures.In this study,two underground pipelines were fabricated using rubber joint... The relative stiffness between underground structures and surrounding soil may significantly influence the dynamic response of such structures.In this study,two underground pipelines were fabricated using rubber joints with varying stiffness,and the corresponding dynamic response was evaluated.Model soils were prepared based on similarity ratios.Next,reduced-scale shaking table tests were conducted to investigate the impact of circular underground structures with varying stiffness joints on the amplification of ground acceleration,dynamic response,and deformation patterns of the underground pipelines.The comparative analysis showed that structures with lower stiffness exert less constraint on the surrounding soil,resulting in a higher amplification factor of ground acceleration.The seismic response of less stiff structures is generally 1.1 to 1.3 times the response of the stiffer structures.Therefore,the seismic response of the variable stiffness pipeline exhibits pronounced characteristics.Rubber joints effectively reduce the seismic response of underground structures,demonstrating favorable isolation effects.Consequently,relative stiffness plays a crucial role in the seismic design of underground structures,and the use of rubber materials in underground structures is advantageous. 展开更多
关键词 shaking table test underground pipeline variable stiffness joint pipeline seismic response
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Experimental and analytical investigations of the dynamic characteristics of a mold transformer with rotary friction dampers based on shaking table tests
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作者 Seung-Jae Lee Ji-Eon Lee +1 位作者 Ngoc Hieu Dinh Kyoung-Kyu Choi 《Earthquake Engineering and Engineering Vibration》 2025年第2期451-472,共22页
In this study, shaking table tests were performed to investigate the dynamic characteristics of a mold transformer. Based on the test results, rotary friction dampers were developed to mitigate the excessive lateral d... In this study, shaking table tests were performed to investigate the dynamic characteristics of a mold transformer. Based on the test results, rotary friction dampers were developed to mitigate the excessive lateral displacement that occurred along the direction of the weak stiffness axis of the mold transformer. In addition, shaking table tests were performed by attaching friction dampers to both sides of the mold transformer. Based on the shaking table test results, the natural frequency, mode vector, and damping ratio of the mold transformer were derived using the transfer function and half-power bandwidth. The test results indicated that the use of friction dampers can decrease the displacement and acceleration response of the mold transformer. Finally, dynamic structural models were established considering the component connectivity and mass distribution of the mold transformer. In addition, a numerical strategy was proposed to calibrate the stiffness coefficients of the mold transformer, thereby facilitating the relationship between generalized mass and stiffness. The results indicated that the analytical model based on the calibration strategy of stiffness coefficients can reasonably simulate the dynamic behavior of the mold transformer using friction dampers with regard to transfer function, displacement, and acceleration response. 展开更多
关键词 mold transformer dynamic characteristics shaking table test rotary friction dampers dynamic structural model stiffness calibration
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Shake table tests and numerical investigations on the seismic response of transmission tower-line systems under strike-slip fault rupture
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作者 Tian Li Yang Meng +3 位作者 Liu Juncai Dong Xu Liu Yuping Xie Quancai 《Earthquake Engineering and Engineering Vibration》 2025年第4期1049-1066,共18页
Transmission tower-line systems(TTLSs)play a crucial role in the long-distance transmission of electrical energy,often necessitating their crossing through active fault areas.However,previous studies have given limite... Transmission tower-line systems(TTLSs)play a crucial role in the long-distance transmission of electrical energy,often necessitating their crossing through active fault areas.However,previous studies have given limited attention to the seismic performance of fault-crossing transmission TTLSs,particularly in terms of considering the impact of permanent ground motion displacements(PGMDs).This study attempts to address this concern by evaluating the seismic performance of TTLSs exposed to fault earthquakes.Three strike-slip ground motions are carefully selected,and the corresponding PGMDs are accurately replicated through baseline adjustment.A meticulously designed and fabricated reduced-scale experimental model of a TTLS is then employed to investigate the influence of the fault crossing location(FCL)on its seismic performance.The shake table tests conducted unequivocally demonstrate that PGMDs significantly amplify the seismic responses of the TTLS and identify the most unfavorable FCL.Furthermore,a finite element model(FEM)is developed and its accuracy is validated by comparing it with the experimental results.Parametric analyses are conducted to explore the effects of fault crossing angles(FCAs)and PGMD amplitudes on the seismic performances of TTLSs.This study is expected to contribute valuable insights for the seismic design and performance analysis of TTLSs crossing fault areas. 展开更多
关键词 transmission tower-line system seismic performance shake table test permanent ground motion displacement fault crossing location
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Phase classification of high entropy alloys with composition,common physical,elemental-property descriptors and periodic table representation
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作者 Shuai LI Jia YANG +2 位作者 Shu LI Dong-rong LIU Ming-yu ZHANG 《Transactions of Nonferrous Metals Society of China》 2025年第6期1855-1874,共20页
Phase classification has a clear guiding significance for the design of high entropy alloys.For mutually exclusive and non-mutually exclusive classifications,the composition descriptors,commonly used physical paramete... Phase classification has a clear guiding significance for the design of high entropy alloys.For mutually exclusive and non-mutually exclusive classifications,the composition descriptors,commonly used physical parameter descriptors,elemental-property descriptors,and descriptors extracted from the periodic table representation(PTR)by the convolutional neural network were collected.Appropriate selection among features with rich information is helpful for phase classification.Based on random forest,the accuracy of the four-label classification and balanced accuracy of the five-label classification were improved to be 0.907 and 0.876,respectively.The roles of the four important features were summarized by interpretability analysis,and a new important feature was found.The model extrapolation ability and the influence of Mo were demonstrated by phase prediction in(CoFeNiMn)_(1-x)Mo_(x).The phase information is helpful for the hardness prediction,the classification results were coupled with the PTR of hardness data,and the prediction error(the root mean square error)was reduced to 56.69. 展开更多
关键词 high entropy alloy phase classification feature engineering periodic table representation convolutional neural network hardness prediction
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Rail displacement measurement in shaking table tests via a method integrating KLT feature tracker and extended Kalman filter
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作者 WANG Huan CHEN Ruoxi +2 位作者 YE Shanshan CHEN Zeqi ZHAO Fei 《Journal of Southeast University(English Edition)》 2025年第2期207-214,共8页
Shaking table tests are widely used to evaluate seismic effects on railway structures,but accurately measuring rail displacement remains a significant challenge owing to the nonlinear characteristics of large displace... Shaking table tests are widely used to evaluate seismic effects on railway structures,but accurately measuring rail displacement remains a significant challenge owing to the nonlinear characteristics of large displacements,ambient noise interference,and limitations in displacement meter installation.In this paper,a novel method that integrates the Kanade-Lucas-Tomasi(KLT)feature tracker with an extended Kalman filter(EKF)is presented for measuring rail displacement during shaking table tests.The method employs KLT feature tracker and a random sample consensus algorithm to extract and track key feature points,while EKF optimally estimates dynamic states by accounting for system noise and observation errors.Shaking table test results demonstrate that the proposed method achieves an acceleration root mean square error of 0.300 m/s^(2)and a correlation with accelerometer data exceeding 99.7%,significantly outper-forming the original KLT approach.This innovative method provides a more efficient and reliable solution for measuring rail displacement under large nonlinear vibrations. 展开更多
关键词 shaking table test rail displacement computer vision Kanade-Lucas-Tomasi(KLT)feature tracker extended Kalman filter(EKF)
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Dynamic response of the ground beneath a high-speed railway based on typical upper Shanghai clays involving water table change
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作者 Jing HU Chengming YE +3 位作者 Juntao JIANG Shujing WU David THOMPSON Xuecheng BIAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第8期787-800,共14页
A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.... A rising water table increases soil water content,reduces soil strength,and amplifies vibrations under identical train loads,thereby posing greater risks to train operations.To investigate this phenomenon,we used a 2.5D finite element(FE)model of a coupled vehicle–embankment–ground system based on Biot’s theory.The ground properties were derived from a typical soil profile of the Yangtze River basin,using geological data from Shanghai,China.The findings indicate that a rise in the water table leads to increased dynamic displacements of both the track and the ground.This amplification effect extends beyond the depth of the water table,impacting the entire embankment–foundation cross-section,and intensifies with higher train speeds.However,the water table rise has a limited impact on the critical speed of trains and dominant frequency contents.The dynamic response of the embankment is more significantly affected by water table rises within the subgrade than by those within the ground.When the water table rises into the subgrade,significant excess pore pressure is generated inside the embankment,causing a substantial drop in effective stress.As a result,the stress path of the soil elements in the subgrade approaches the Mohr-Coulomb failure line,increasing the likelihood of soil failure. 展开更多
关键词 Dynamic response Excess pore pressures Water table rise High-speed train 2.5D finite element(FE)model
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Estimation of regional physical imports and exports of EW-MFA in China using monetary input-output tables 被引量:2
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作者 Nan LI Tianzhu ZHANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2013年第2期242-254,共13页
Given the statistical gaps in material flow among provinces in China, a method was introduced to estimate regional physical imports and exports (RPIE), which includes international and interregional imports/ exports... Given the statistical gaps in material flow among provinces in China, a method was introduced to estimate regional physical imports and exports (RPIE), which includes international and interregional imports/ exports. This method uses provincial monetary input- output tables (MIOT) and international trade statistics. A coefficient matrix representing correlations between monetary value and physical mass for years 2000-2009 was obtained based on a detailed commodity classification and 22 material production sectors in MIOT. With the coefficient matrix as reference, RPIE was measured. Pilot calculation of both regional physical trade balance and domestic material consumption, as well as a brief analysis of these methods, were conducted using 2002 data. 展开更多
关键词 economy-wide material flow accounts (EW-MFA) monetary input-output table (M1OT) regionalphysical imports and exports estimation
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Using Fundamental Economic Structures to Estimate Chinese Regional Input-Output Tables
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作者 Xuemei Jiang Rencheng Tong 《Journal of Systems Science and Information》 2008年第3期227-236,共10页
The estimation of regional input-output tables is well discussed in the literature and a large variety of methods exist. In this paper we will use the concept of fundamental economic structure (FES) to estimate the ... The estimation of regional input-output tables is well discussed in the literature and a large variety of methods exist. In this paper we will use the concept of fundamental economic structure (FES) to estimate the matrix of intermediate deliveries for some "missing" region(s). Furthermore, the estimates will be compared with the estimates obtained from "traditional" estimating techniques, including regionalization on the basis of the national table, and borrowing coefficients from similar regions. The results show FES is very helpful for compiling regional tables of China. 展开更多
关键词 FES regional input-output tables ESTIMATION
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Integral precession calibration method of PIGA on linear vibration table 被引量:2
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作者 Chuang SUN Shun-qing REN +1 位作者 Jun-wei CAO Ru HUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第3期219-236,共18页
Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a... Linear vibration table can provide harmonic accelerations to excite the nonlinear error terms of Pendulous Integrating Gyro Accelerometer(PIGA).Integral precession calibration method is proposed to calibrate PIGA on a linear vibration table in this paper.Based on the precise expressions of PIGA’s inputs,the error calibration model of PIGA is established.Precession angular velocity errors of PIGA are suppressed by integer periodic precession and the errors caused by non-integer periods vibrating are compensated.The complete calibration process,including planning,preparation,PIGA testing,and coefficient identification,is designed to optimize the test operations and evaluate the calibration results.The effect of the main errors on calibration uncertainty is analyzed and the relative sensitivity function is proposed to further optimize the test positions.Experimental and simulation results verify that the proposed 10-position calibration method can improve calibration uncertainties after compensating for the related errors.The order of calibration uncertainties of the second-and third-order coefficients are decreased to 10^(-8)(rad.s^(-1))/g^(2)and 10^(-8)(rad.s^(-1))/g3,respectively.Compared with the other two classical calibration methods,the calibration uncertainties of PIGA’s nonlinear error coefficients can be effectively reduced and the proportional residual errors are decreased less than 3×10-6(rad.s^(-1))/g by using the proposed calibration method. 展开更多
关键词 PIGA Linear vibration table Vibration measurement CALIBRATION Error analysis Uncertainty analysis
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