The Chikugo Model is used to estimate radiative dryness indexes (RDI) and net primary productivity (NPP) of vegetation zones in China by calculating cli-matic parameters. That provides the water-heat equilibrium condi...The Chikugo Model is used to estimate radiative dryness indexes (RDI) and net primary productivity (NPP) of vegetation zones in China by calculating cli-matic parameters. That provides the water-heat equilibrium condition, potential primary production for natural vegetation in various vegetation zones, and their geographical distribution pattern. That could be used as the basis for study the effect of global climate change on ecosystems.展开更多
Purpose: This paper aims to investigate the scientific productivity of China's science system. Design/methodology/approach: This paper employs the Malmquist productivity index(MPI) based on Data Envelopment Analys...Purpose: This paper aims to investigate the scientific productivity of China's science system. Design/methodology/approach: This paper employs the Malmquist productivity index(MPI) based on Data Envelopment Analysis(DEA).Findings: The results reveal that the overall efficiency of Chinese universities increased significantly from 2009 to 2016, which is mainly driven by technological progress. From the perspective of the functions of higher education, research and transfer activities perform better than the teaching activities.Research limitations: As an implication, the indicator selection mechanism, investigation period and the MPI model can be further extended in the future research.Practical implications: The results indicate that Chinese education administrative departments should take actions to guide and promote the teaching activities and formulate reasonable resource allocation regulations to reach the balanced development in Chinese universities.Originality/value: This paper selects 58 Chinese universities and conducts a quantified measurement during the period 2009–2016. Three main functional activities of universities(i.e. teaching, researching, and application) are innovatively categorized into different schemes, and we calculate their performance, respectively.展开更多
Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different e...Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production.展开更多
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ...Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index.展开更多
The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, instit...The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, institutions or policies that promote soybean production development in China. In this paper, TFP growth for soybean production was estimated for a panel data of 10 major soybean producing provinces from 2005 to 2017. Results reveal that TFP grew at an average rate of 1.3% over the whole period, with technical progress contributing 2.3% and efficiency change providing the other -1.0%. The change of TFP for soybean production over that time, whether increase or decline, was mainly derived by technical change except in three years (2005-2007). Positive TFP growth in the provinces of Liaoning and Inner Mongolia, and negative TFP growth in Hebei and Anhui were mainly driven by efficiency change, specifically scale efficiency change except pure technical efficiency in Liaoning.展开更多
This study reviews productivity growth in the five major transportation industries in the United States (airline, truck, rail, pipeline, and water) and the pooled transportation industry from 2004 to 2011. We measure ...This study reviews productivity growth in the five major transportation industries in the United States (airline, truck, rail, pipeline, and water) and the pooled transportation industry from 2004 to 2011. We measure the average productivity for these eight years by state in each transportation industry and the annual average productivity by transportation industry. The major findings are that the U.S. transportation industry shows strong and positive productivity growth except that in the years of the global financial crisis in 2007, 2008, and 2010, and among the five transportation industries, the rail and water sectors show the highest productivity growth in 2011.展开更多
Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extens...Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extensive stage.China’s economy has shifted from a high-speed growth phase to a high-quality development phase.In this study,we analyzed three major urban agglomerations’total factor productivity index dynamically by means of Malmquist productivity i?ndex method.The results showed that MPI of Beijing-Tianjin-Hebei urban agglomeration was the highest,as the reasons of the effectiveness of dual-wheel driving both the technology progress and the cluster scale.The mean of MPI of Yangtze River Delta urban agglomeration was fallen into decline by an average of 1.3%annually due to the rate of increase of the size of the cluster towards to optimal frontier was inferior to the relative risk reduction of technology progress.Pearl River Delta urban agglomeration MPI declined by an average of 2.2%annually as a result of the contribution of technology progress reducing.The study of the economic performance of three major urban agglomerations provides a theoretical basis and important practical value for urban development of high quality optimization.展开更多
For some time, two major kinds of Total Factor Productivity (TFP) have existed independently of each other: the Solow residual and the Malmquist Productivity Index (MPI). The Solow residual was introduced in macr...For some time, two major kinds of Total Factor Productivity (TFP) have existed independently of each other: the Solow residual and the Malmquist Productivity Index (MPI). The Solow residual was introduced in macro economic growth models, and the MPI has been used in micro economics and management studies. As both indices were developed independently, few studies utilize both together and compare the results. This paper uses the same data to compare the two productivity indices by setting to determine the economic implications of combining the two indices. We discovered that we could decompose TFP with each aspect of the Soiow residual and MPI. We could then interpret their relationship in the business cycle. Our results indicated that the frontier shift in MPI of Japanese firms often occurred when the Solow residual increased, meaning that improving oroductivitv with the Solow residual could be generated by a firm that could shift new production frontiers.展开更多
The calculation of the overall profit Malmquist productivity index(MPI)requires precise and accurate information on the input,output,input-output prices of each decision making unit(DMU).However,in many situations,som...The calculation of the overall profit Malmquist productivity index(MPI)requires precise and accurate information on the input,output,input-output prices of each decision making unit(DMU).However,in many situations,some inputs and/or outputs and input-output prices are imprecise.As such,we consider the overall profit MPI problem when the input,output,and input-output prices are imprecise and vary over intervals,showing that method(MCM 54:2827–2838,2011)has some shortfalls.To remedy these shortfalls,we propose another method for measuring the overall profit MPI when the inputs,outputs,and price vectors vary over intervals.That is,to calculate the overall profit efficiency intervals,cone-ratio data envelopment analysis models can be applied to the incorporated information as weight restrictions.Further,we provide a new approach to calculating the upper bound of the overall profit efficiency of each DMU.A numerical example is provided for illustrating the proposed method.展开更多
This paper estimates and decomposes the output-oriented three-stage cost Malmquist productivity index of the Taiwan Residents biotech and biopharmaceutical (B&BP) industry in 2004-2007 periods. The empirical estima...This paper estimates and decomposes the output-oriented three-stage cost Malmquist productivity index of the Taiwan Residents biotech and biopharmaceutical (B&BP) industry in 2004-2007 periods. The empirical estimations proceed in three stages. Following the methodology of Yang and Huang (2009) with the assumption of variable return to scale (VRS) in the first stage, the original cost Malmquist productivity index (CM) is decomposed into five sources of productivity change: pure technical efficiency change, technical change, allocative efficiency change (AEC), input-price effect, and cost scale efficiency change. The method of Yang and Huang (2009) is an excellent contribution, but it did not deal with the exogenous environmental variables and noises. In the second stage, the original input variables are adjusted by the exogenous environmental variables. Finally, adjusted input variables produced by the second stage are reused for obtaining the reality of CM in the third stage.展开更多
[Objective] The aim was to research relationship between SPAD decline index after full-heading stage (SDIFHS) and productivity of rice. fertilized with nitro- gen in order to provide theoretical and practical refere...[Objective] The aim was to research relationship between SPAD decline index after full-heading stage (SDIFHS) and productivity of rice. fertilized with nitro- gen in order to provide theoretical and practical references for selection and breed- ing of rice varieties. [Method] From 2008 to 2010, 18 mid-season hybrid rice vari- eties were researched every year to explore relationship' between SDIFHS and pro- ductivity of rice fertilized with nitrogen. [Result] The productivity of rice fertilized with nitrogen was of extremely significant positive corretation with SDIFHS, because the higher SPAD decline index is, the higher LAI decline index and the transformation ratio of dry matter to spikes in overground plant would be. [Conclusion] The re- search established a new method to predict productivity of rice fertilized with nitro- gen based on SPAD decline index.展开更多
In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause productio...In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause production logistics bottleneck frequently shift, and make decisions of production planning and control based on formed bottleneck deviated from practical production process. Considering these factors, present researches mainly apply afterwards control to optimize production process to passively adapt to bottleneck changes If the direction of bottleneck shifting can be accurately forecasted, the transition from afterwards control of chasing bottleneck to beforehand control can be realized. Therefore, aiming at the phenomenon of production logistics bottleneck shifting under uncertain manufacturing circumstances, this paper starts off with dynamic property of capability and requirement and then builds the concepts of bottleneck degree and bottleneck index to describe dynamic bottleneck characteristic of production unit; taken production capability, production load and quality assurance capability into consideration, mathematical model of bottleneck index is established to measure bottleneck degree accurately, consequently, quantitative research on mechanism of production logistics shifting is achieved. Based on bottleneck index, the prediction model of production logistics bottleneck is founded to predict dynamic change of bottleneck accurately. Finally, an example of forecasting and monitoring the production logistics bottleneck in one manufacturing shop is given to testify the validation and practicability of the prediction method.展开更多
Net primary productivity(NPP), as an important variable and ecological indicator in grassland ecosystems, can reflect environmental change and the carbon budget level. The Ili River Valley is a wetland nestled in th...Net primary productivity(NPP), as an important variable and ecological indicator in grassland ecosystems, can reflect environmental change and the carbon budget level. The Ili River Valley is a wetland nestled in the hinterland of the Eurasian continent, which responds sensitively to the global climate change. Understanding carbon budget and their responses to climate change in the ecosystem of Ili River Valley has a significant effect on the adaptability of future climate change and sustainable development. In this study, we calculated the NPP and analyzed its spatio-temporal pattern of the Ili River Valley during the period 2000–2014 using the normalized difference vegetation index(NDVI) and an improved Carnegie-Ames-Stanford(CASA) model. Results indicate that validation showed a good performance of CASA over the study region, with an overall coefficient of determination(R2) of 0.65 and root mean square error(RMSE) of 20.86 g C/(m^2·a). Temporally, annual NPP of the Ili River Valley was 599.19 g C/(m^2·a) and showed a decreasing trend from 2000 to 2014, with an annual decrease rate of –3.51 g C/(m^2·a). However, the spatial variation was not consistent, in which 55.69% of the areas showed a decreasing tendency, 12.60% of the areas remained relatively stable and 31.71% appeared an increasing tendency. In addition, the decreasing trends in NPP were not continuous throughout the 15-year period, which was likely being caused by a shift in climate conditions. Precipitation was found to be the dominant climatic factor that controlled the inter-annual variability in NPP. Furthermore, the correlations between NPP and climate factors differed along the vertical zonal. In the medium-high altitudes of the Ili River Valley, the NPP was positively correlated to precipitation and negatively correlated to temperature and net radiation. In the low-altitude valley and high-altitude mountain areas, the NPP showed a negative correlation with precipitation and a weakly positive correlation with temperature and net radiation. The results suggested that the vegetation of the Ili River Valley degraded in recent years, and there was a more complex mechanism of local hydrothermal redistribution that controlled the growth of vegetation in this valley ecosystem.展开更多
China implemented the public hospital reform in 2012. This study utilized bootstrapping data envelopment analysis(DEA) to evaluate the technical efficiency(TE) and productivity of county public hospitals in Easter...China implemented the public hospital reform in 2012. This study utilized bootstrapping data envelopment analysis(DEA) to evaluate the technical efficiency(TE) and productivity of county public hospitals in Eastern, Central, and Western China after the 2012 public hospital reform. Data from 127 county public hospitals(39, 45, and 43 in Eastern, Central, and Western China, respectively) were collected during 2012–2015. Changes of TE and productivity over time were estimated by bootstrapping DEA and bootstrapping Malmquist. The disparities in TE and productivity among public hospitals in the three regions of China were compared by Kruskal–Wallis H test and Mann–Whitney U test. The average bias-corrected TE values for the four-year period were 0.6442, 0.5785, 0.6099, and 0.6094 in Eastern, Central, and Western China, and the entire country respectively, with average non-technical efficiency, low pure technical efficiency(PTE), and high scale efficiency found. Productivity increased by 8.12%, 0.25%, 12.11%, and 11.58% in China and its three regions during 2012–2015, and such increase in productivity resulted from progressive technological changes by 16.42%, 6.32%, 21.08%, and 21.42%, respectively. The TE and PTE of the county hospitals significantly differed among the three regions of China. Eastern and Western China showed significantly higher TE and PTE than Central China. More than 60% of county public hospitals in China and its three areas operated at decreasing return scales. There was a considerable space for TE improvement in county hospitals in China and its three regions. During 2012–2015, the hospitals experienced progressive productivity; however, the PTE changed adversely. Moreover, Central China continuously achieved a significantly lower efficiency score than Eastern and Western China. Decision makers and administrators in China should identify the causes of the observed inefficiencies and take appropriate measures to increase the efficiency of county public hospitals in the three areas of China, especially in Central China.展开更多
Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisf...Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisfaction from the equipment. The user satisfaction could be measured as machine effectiveness.Mining literatures on performance improvement and optimization of equipment operations assert importance of availability, utilization and production performance as key parameters. These three parameters are useful for evaluating effectiveness of equipment. Mine production index(MPI), which can represent the effect of these factors, has been applied for continuous operation in mining. MPI uses Fuzzy Delphi Analytical Hierarchy Process to determine importance of each three parameter for individual equipment. A case study in a Swedish open pit mine was done to evaluate the field application of MPI.The results reveal that crusher is the bottleneck equipment in studied mine. As a methodical approach,an algorithm which uses MPI and detects bottleneck in continuous mining operation has been proposed.展开更多
Forest net primary productivity (NPP) is a key parameter for forest monitoring and management. In this study, monthly and annual forest NPP in the northeastern China from 1982 to 2010 were simulated by using Carnegi...Forest net primary productivity (NPP) is a key parameter for forest monitoring and management. In this study, monthly and annual forest NPP in the northeastern China from 1982 to 2010 were simulated by using Carnegie-Ames-Stanford Approach (CASA) model with normalized difference vegetation index (NDVI) sequences derived from Advanced Very High Resolution Radiometer (AVHRR) Global Invento y Modeling and Mapping Studies (GIMMS) and Terra Moderate Resolution Imaging Spectroradiometer (MODIS) products. To address the problem of data inconsistency between AVHRR and MODIS data, a per-pixel unary linear regres- sion model based on least ~;quares method was developed to derive the monthly NDVI sequences. Results suggest that estimated forest NPP has mean relative error of 18.97% compared to observed NPP from forest inventory. Forest NPP in the northeastern China in- creased significantly during the twenty-nine years. The results of seasonal dynamic show that more clear increasing trend of forest NPP occurred in spring and awmnn. This study also examined the relationship between forest NPP and its driving forces including the climatic and anthropogenic factors. In spring and winter, temperature played the most pivotal role in forest NPR In autumn, precipitation acted as the most importanl factor affecting forest NPP, while solar radiation played the most important role in the summer. Evaportran- spiration had a close correlation with NPP for coniferous forest, mixed coniferous broadleaved forest, and broadleaved deciduous forest. Spatially, forest NPP in the Da Hinggan Mountains was more sensitive to climatic changes than in the other ecological functional re- gions. In addition to climalie change, the degradation and improvement of forests had important effects on forest NPP. Results in this study are helpful for understanding the regional carbon sequestration and can enrich the cases for the monitoring of vegetation during long time series.展开更多
[Objective]The paper was to investigate the effects of dietary crude fiber level on production performance,organ index and serum biochemical parameters of Dingan geese aged from 1 to 28 days.[Method]A total of 144 1-d...[Objective]The paper was to investigate the effects of dietary crude fiber level on production performance,organ index and serum biochemical parameters of Dingan geese aged from 1 to 28 days.[Method]A total of 144 1-day-old Dingan geese with the same genetic background and similar initial weight(88.75±0.21g)were randomly assigned into 3 groups with 4 replicates per group and 12 geese per replicate,and fed with the diets containing 2.56%,3.52% and 4.48% crude fiber,respectively.The trial lasted 28 d.[Result]1)The final weight and daily gain of 3.52% CF group were significantly higher than those of 2.56% CF group(P<0.05);the feed/gain ratio was markedly lower than that of 2.56% CF group(P<0.05).2)The slaughter rate,semi-eviscerated rate and leg muscle rate of 3.52% CF group were higher than those of 2.56% and 4.48% CF groups(P>0.05).3)As the dietary crude fiber levels rose,the abdominal fat rate showed a downward trend(P>0.05).4)The liver index of 3.52% CF group was significantly higher than that of 2.56% CF group(P<0.05).4)Compared with 2.5%and 4.48% CF groups,the serum albumin concentrations of 3.52% CF group markedly increased(P<0.05),the serum total protein and globin contents were higher(P>0.05),but the serum uric acid level was lower(P>0.05).[Conclusion]When the crude fiber level was 3.52%,the production performances of Dingan geese aged from 1 to 28 days were better,and the liver index and serum albumin level could be obviously improved.展开更多
Drought, as a recurring extreme climate event, affects the structure, function, and process of terrestrial ecosystems. Despite the increasing occurrence and intensity of the drought in the past decade in Southwestern ...Drought, as a recurring extreme climate event, affects the structure, function, and process of terrestrial ecosystems. Despite the increasing occurrence and intensity of the drought in the past decade in Southwestern China, the impacts of continuous drought events on vegetation in this region remain unclear. During 2001–2012, Southwestern China experienced the severe drought events from 2009 to 2011. Our aim is to characterize drought conditions in the Southwestern China and explore the impacts on the vegetation condition and terrestrial ecosystem productivity. The Standardized Precipitation Index(SPI) was used to characterize drought area and intensity and a light-use efficiency model was used to explore the effect of drought on the terrestrial ecosystem productivity with Moderate Resolution Imaging Spectrometer(MODIS) data. The SPI captured the major drought events in Southwestern China during the study period, indicated that the 12-year period of this study included both ‘normal' precipitation years and two severe drought events in 2009–2010 and 2011. Results showed that vegetation greenness(Normalized Difference Vegetation Index, NDVI and Enhanced Vegetation Index, EVI) both declined in 2009/2010 drought, but the 2011 drought resulted in less declines of vegetation greenness and productivity due to shorten drought duration and rising temperature. Meanwhile, it was about 5 months lapse between drought events and maximum declines in vegetation greenness for 2009/2010 drought events. In addition, forest, grassland and cropland revealed significant different ecosystem responses to drought. It indicated that grassland showed an early sensitivity to drought, while cropland was the most sensitive to water deficit and forest was more resilient to drought. This study suggests that it is necessary to detect the difference responses of ecosystem to drought in a regional area with satellite data and ecosystem model.展开更多
With global warming, the great changes in the patterns of plant growth have occurred. The conditions in early spring and late autumn have changed the process of vegetation photosynthesis, which are expected to have a ...With global warming, the great changes in the patterns of plant growth have occurred. The conditions in early spring and late autumn have changed the process of vegetation photosynthesis, which are expected to have a significant impact on net primary productivity(NPP) and affect the global carbon cycle. Currently, the seasonal response characteristics of NPP to phenological changes in dryland ecosystems are still not well defined. This article calibrated and analyzed the normalized difference vegetation index(NDVI)time series of Advanced Very-High-Resolution Radiometer(AVHRR) data from 1982 to 2015 in the Loess Plateau, China. The spatial and temporal distributions of vegetation phenology and NPP in the Loess Plateau under semihumid and semiarid conditions were investigated. The seasonal variation in the NPP response to vegetation phenology under the climate change was also analyzed. The results showed that, different from the northern forest, there was distinct spatial heterogeneity in the effect of climate change on the dynamic change in vegetation growth in the Loess Plateau: 1) an advance of the start of the growing season(SOS) and a delay of the end of the growing season(EOS) significantly increased the NPP in spring and autumn, respectively, in the humid southeast;2) in the arid northwest, the NPP did not significantly increase in spring and autumn but significantly decreased in summer.展开更多
In order to study the effects of replacing different proportions of silage maize with silage sweet sorghum treated by different fermentation methods on the production performance and blood biochemical indexes of dairy...In order to study the effects of replacing different proportions of silage maize with silage sweet sorghum treated by different fermentation methods on the production performance and blood biochemical indexes of dairy cows,25 Chinese Holstein lactating cows were randomly divided into 5 groups,5 in each group.The control check (CK) was fed the basal diet;for the experimental group 1 and the experimental group 2,50% of the silage maize in the basal diet was replaced with the additive silage sweet sorghum and the conventional silage sweet sorghum,respectively;and as to the experimental group 3 and the experimental group 4,all the silage maize in the basal diet was replaced with additive silage sweet sorghum and conventional silage sweet sorghum,respectively.The preliminary trial period was 7 d,and the trial period was 35 d.The results showed that the experimental group 1 and the experimental group 3 had the dry matter intake significantly higher than that of the experimental group 2,the experimental group 4 and the CK ( P <0.05).The daily milk yields of the experimental group 1 and the experimental group 2 were significantly lower than that of the CK ( P <0.05),and the experimental group 3 and the experimental group 4 were significantly lower than the experimental group 1 and the experimental group 2 ( P <0.05).The milk protein percentage of the experimental group 2 was extremely significantly higher than that of the experimental group 4 ( P <0.01).The experimental group 1,the experimental group 2 and the experimental group 3 showed the blood glucose levels extremely significantly higher than that in the CK ( P <0.01).The blood urea nitrogen contents in the experimental group 2 and the experimental group 4 were significantly higher than those in the experimental group 1 and the CK ( P <0.01).There were no significant differences in other blood biochemical indexes between various groups ( P >0.05).It is feasible to use silage sweet sorghum to feed dairy cows,but the proportion should not be too large,and attention should be paid to the energy and nitrogen balance of the diet.展开更多
文摘The Chikugo Model is used to estimate radiative dryness indexes (RDI) and net primary productivity (NPP) of vegetation zones in China by calculating cli-matic parameters. That provides the water-heat equilibrium condition, potential primary production for natural vegetation in various vegetation zones, and their geographical distribution pattern. That could be used as the basis for study the effect of global climate change on ecosystems.
基金the financial support from National Natural Science Foundation (NSFC, No. 71671181)
文摘Purpose: This paper aims to investigate the scientific productivity of China's science system. Design/methodology/approach: This paper employs the Malmquist productivity index(MPI) based on Data Envelopment Analysis(DEA).Findings: The results reveal that the overall efficiency of Chinese universities increased significantly from 2009 to 2016, which is mainly driven by technological progress. From the perspective of the functions of higher education, research and transfer activities perform better than the teaching activities.Research limitations: As an implication, the indicator selection mechanism, investigation period and the MPI model can be further extended in the future research.Practical implications: The results indicate that Chinese education administrative departments should take actions to guide and promote the teaching activities and formulate reasonable resource allocation regulations to reach the balanced development in Chinese universities.Originality/value: This paper selects 58 Chinese universities and conducts a quantified measurement during the period 2009–2016. Three main functional activities of universities(i.e. teaching, researching, and application) are innovatively categorized into different schemes, and we calculate their performance, respectively.
基金Supported by the National Natural Science Foundation of China(No.51966013)Inner Mongolia Natural Science Foundation Jieqing Project(No.2023JQ04)+1 种基金the National Natural Science Foundation of China(No.51966018)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.STZC202230).
文摘Power quality improvements help guide and solve the problems of inefficient energy production and unstable power output in wind power systems.The purpose of this paper is mainly to explore the influence of different energy storage batteries on various power quality indicators by adding different energy storage devices to the simulated wind power system,and to explore the correlation between systementropy generation and various indicators,so as to provide a theoretical basis for directly improving power quality by reducing loss.A steady-state experiment was performed by replacing the wind wheel with an electric motor,and the output power qualities of the wind power systemwith andwithout energy storagewere compared and analyzed.Moreover,the improvement effect of different energy storage devices on various indicatorswas obtained.Then,based on the entropy theory,the loss of the internal components of the wind power system generator is simulated and explored by Ansys software.Through the analysis of power quality evaluation indicators,such as current harmonic distortion rate,frequency deviation rate,and voltage fluctuation,the correlation between entropy production and each evaluation indicator was explored to investigate effective methods to improve power quality by reducing entropy production.The results showed that the current harmonic distortion rate,voltage fluctuation,voltage deviation,and system entropy production are positively correlated in the tests and that the power factor is negatively correlated with system entropy production.In the frequency range,the frequency deviationwas not significantly correlated with the systementropy production.
基金the Special Project of the National Science Foundation of China(NSFC)“Open Development of China’s Trade and Investment:Basic Patterns,Overall Effects,and the Dual Circulations Paradigm”(Grant No.72141309)NSFC General Project“GVC Restructuring Effect of Emergent Public Health Incidents:Based on the General Equilibrium Model Approach of the Production Networks Structure”(Grant No.72073142)+1 种基金NSFC General Project“China’s Industrialization Towards Mid-and High-End Value Chains:Theoretical Implications,Measurement and Analysis”(Grant No.71873142)the Youth project of The National Social Science Fund of China“Research on the green and low-carbon development path and policy optimization of China’s foreign trade under the goal of‘dual carbon’”(Grant No.22CJY019).
文摘Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index.
文摘The low and slowly increasing soybean yield restricts the development of soybean production. Accurate measures of total factor productivity (TFP) for soybean production can be helpful in identifying conditions, institutions or policies that promote soybean production development in China. In this paper, TFP growth for soybean production was estimated for a panel data of 10 major soybean producing provinces from 2005 to 2017. Results reveal that TFP grew at an average rate of 1.3% over the whole period, with technical progress contributing 2.3% and efficiency change providing the other -1.0%. The change of TFP for soybean production over that time, whether increase or decline, was mainly derived by technical change except in three years (2005-2007). Positive TFP growth in the provinces of Liaoning and Inner Mongolia, and negative TFP growth in Hebei and Anhui were mainly driven by efficiency change, specifically scale efficiency change except pure technical efficiency in Liaoning.
文摘This study reviews productivity growth in the five major transportation industries in the United States (airline, truck, rail, pipeline, and water) and the pooled transportation industry from 2004 to 2011. We measure the average productivity for these eight years by state in each transportation industry and the annual average productivity by transportation industry. The major findings are that the U.S. transportation industry shows strong and positive productivity growth except that in the years of the global financial crisis in 2007, 2008, and 2010, and among the five transportation industries, the rail and water sectors show the highest productivity growth in 2011.
文摘Forty years of reform and opening up,China has become to the world’s second-largest economy with great success.However,it is an undoubted actuality that the economic mode of Chinese development is still at the extensive stage.China’s economy has shifted from a high-speed growth phase to a high-quality development phase.In this study,we analyzed three major urban agglomerations’total factor productivity index dynamically by means of Malmquist productivity i?ndex method.The results showed that MPI of Beijing-Tianjin-Hebei urban agglomeration was the highest,as the reasons of the effectiveness of dual-wheel driving both the technology progress and the cluster scale.The mean of MPI of Yangtze River Delta urban agglomeration was fallen into decline by an average of 1.3%annually due to the rate of increase of the size of the cluster towards to optimal frontier was inferior to the relative risk reduction of technology progress.Pearl River Delta urban agglomeration MPI declined by an average of 2.2%annually as a result of the contribution of technology progress reducing.The study of the economic performance of three major urban agglomerations provides a theoretical basis and important practical value for urban development of high quality optimization.
文摘For some time, two major kinds of Total Factor Productivity (TFP) have existed independently of each other: the Solow residual and the Malmquist Productivity Index (MPI). The Solow residual was introduced in macro economic growth models, and the MPI has been used in micro economics and management studies. As both indices were developed independently, few studies utilize both together and compare the results. This paper uses the same data to compare the two productivity indices by setting to determine the economic implications of combining the two indices. We discovered that we could decompose TFP with each aspect of the Soiow residual and MPI. We could then interpret their relationship in the business cycle. Our results indicated that the frontier shift in MPI of Japanese firms often occurred when the Solow residual increased, meaning that improving oroductivitv with the Solow residual could be generated by a firm that could shift new production frontiers.
文摘The calculation of the overall profit Malmquist productivity index(MPI)requires precise and accurate information on the input,output,input-output prices of each decision making unit(DMU).However,in many situations,some inputs and/or outputs and input-output prices are imprecise.As such,we consider the overall profit MPI problem when the input,output,and input-output prices are imprecise and vary over intervals,showing that method(MCM 54:2827–2838,2011)has some shortfalls.To remedy these shortfalls,we propose another method for measuring the overall profit MPI when the inputs,outputs,and price vectors vary over intervals.That is,to calculate the overall profit efficiency intervals,cone-ratio data envelopment analysis models can be applied to the incorporated information as weight restrictions.Further,we provide a new approach to calculating the upper bound of the overall profit efficiency of each DMU.A numerical example is provided for illustrating the proposed method.
文摘This paper estimates and decomposes the output-oriented three-stage cost Malmquist productivity index of the Taiwan Residents biotech and biopharmaceutical (B&BP) industry in 2004-2007 periods. The empirical estimations proceed in three stages. Following the methodology of Yang and Huang (2009) with the assumption of variable return to scale (VRS) in the first stage, the original cost Malmquist productivity index (CM) is decomposed into five sources of productivity change: pure technical efficiency change, technical change, allocative efficiency change (AEC), input-price effect, and cost scale efficiency change. The method of Yang and Huang (2009) is an excellent contribution, but it did not deal with the exogenous environmental variables and noises. In the second stage, the original input variables are adjusted by the exogenous environmental variables. Finally, adjusted input variables produced by the second stage are reused for obtaining the reality of CM in the third stage.
基金Supported by Southuest China Rice Innovation System and Crop High-yielding Project by Science and Technology (2011BAD02A05) Transformation Project of Agricultural Fruits into Capitals (2006GB2F000256)+2 种基金Sichuan Academic Leaders Training FundSichuan Rice Cultivation Key ProjectSichuan Financial Distribution Project~~
文摘[Objective] The aim was to research relationship between SPAD decline index after full-heading stage (SDIFHS) and productivity of rice. fertilized with nitro- gen in order to provide theoretical and practical references for selection and breed- ing of rice varieties. [Method] From 2008 to 2010, 18 mid-season hybrid rice vari- eties were researched every year to explore relationship' between SDIFHS and pro- ductivity of rice fertilized with nitrogen. [Result] The productivity of rice fertilized with nitrogen was of extremely significant positive corretation with SDIFHS, because the higher SPAD decline index is, the higher LAI decline index and the transformation ratio of dry matter to spikes in overground plant would be. [Conclusion] The re- search established a new method to predict productivity of rice fertilized with nitro- gen based on SPAD decline index.
基金supported by Anhui Provincial Natural Science Foundationof China (Grant No. 090414154)
文摘In modern manufacturing pattern, there are many uncertain factors in the modern manufacturing process, such as changes of product attribute, changes of manufacturing resources' state, and so on, which cause production logistics bottleneck frequently shift, and make decisions of production planning and control based on formed bottleneck deviated from practical production process. Considering these factors, present researches mainly apply afterwards control to optimize production process to passively adapt to bottleneck changes If the direction of bottleneck shifting can be accurately forecasted, the transition from afterwards control of chasing bottleneck to beforehand control can be realized. Therefore, aiming at the phenomenon of production logistics bottleneck shifting under uncertain manufacturing circumstances, this paper starts off with dynamic property of capability and requirement and then builds the concepts of bottleneck degree and bottleneck index to describe dynamic bottleneck characteristic of production unit; taken production capability, production load and quality assurance capability into consideration, mathematical model of bottleneck index is established to measure bottleneck degree accurately, consequently, quantitative research on mechanism of production logistics shifting is achieved. Based on bottleneck index, the prediction model of production logistics bottleneck is founded to predict dynamic change of bottleneck accurately. Finally, an example of forecasting and monitoring the production logistics bottleneck in one manufacturing shop is given to testify the validation and practicability of the prediction method.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA19030204)the West Light Program of Chinese Academy of Sciences(2015-XBQN-B-17)
文摘Net primary productivity(NPP), as an important variable and ecological indicator in grassland ecosystems, can reflect environmental change and the carbon budget level. The Ili River Valley is a wetland nestled in the hinterland of the Eurasian continent, which responds sensitively to the global climate change. Understanding carbon budget and their responses to climate change in the ecosystem of Ili River Valley has a significant effect on the adaptability of future climate change and sustainable development. In this study, we calculated the NPP and analyzed its spatio-temporal pattern of the Ili River Valley during the period 2000–2014 using the normalized difference vegetation index(NDVI) and an improved Carnegie-Ames-Stanford(CASA) model. Results indicate that validation showed a good performance of CASA over the study region, with an overall coefficient of determination(R2) of 0.65 and root mean square error(RMSE) of 20.86 g C/(m^2·a). Temporally, annual NPP of the Ili River Valley was 599.19 g C/(m^2·a) and showed a decreasing trend from 2000 to 2014, with an annual decrease rate of –3.51 g C/(m^2·a). However, the spatial variation was not consistent, in which 55.69% of the areas showed a decreasing tendency, 12.60% of the areas remained relatively stable and 31.71% appeared an increasing tendency. In addition, the decreasing trends in NPP were not continuous throughout the 15-year period, which was likely being caused by a shift in climate conditions. Precipitation was found to be the dominant climatic factor that controlled the inter-annual variability in NPP. Furthermore, the correlations between NPP and climate factors differed along the vertical zonal. In the medium-high altitudes of the Ili River Valley, the NPP was positively correlated to precipitation and negatively correlated to temperature and net radiation. In the low-altitude valley and high-altitude mountain areas, the NPP showed a negative correlation with precipitation and a weakly positive correlation with temperature and net radiation. The results suggested that the vegetation of the Ili River Valley degraded in recent years, and there was a more complex mechanism of local hydrothermal redistribution that controlled the growth of vegetation in this valley ecosystem.
基金supported by the National Natural Science Foundation of China(No.71473099)
文摘China implemented the public hospital reform in 2012. This study utilized bootstrapping data envelopment analysis(DEA) to evaluate the technical efficiency(TE) and productivity of county public hospitals in Eastern, Central, and Western China after the 2012 public hospital reform. Data from 127 county public hospitals(39, 45, and 43 in Eastern, Central, and Western China, respectively) were collected during 2012–2015. Changes of TE and productivity over time were estimated by bootstrapping DEA and bootstrapping Malmquist. The disparities in TE and productivity among public hospitals in the three regions of China were compared by Kruskal–Wallis H test and Mann–Whitney U test. The average bias-corrected TE values for the four-year period were 0.6442, 0.5785, 0.6099, and 0.6094 in Eastern, Central, and Western China, and the entire country respectively, with average non-technical efficiency, low pure technical efficiency(PTE), and high scale efficiency found. Productivity increased by 8.12%, 0.25%, 12.11%, and 11.58% in China and its three regions during 2012–2015, and such increase in productivity resulted from progressive technological changes by 16.42%, 6.32%, 21.08%, and 21.42%, respectively. The TE and PTE of the county hospitals significantly differed among the three regions of China. Eastern and Western China showed significantly higher TE and PTE than Central China. More than 60% of county public hospitals in China and its three areas operated at decreasing return scales. There was a considerable space for TE improvement in county hospitals in China and its three regions. During 2012–2015, the hospitals experienced progressive productivity; however, the PTE changed adversely. Moreover, Central China continuously achieved a significantly lower efficiency score than Eastern and Western China. Decision makers and administrators in China should identify the causes of the observed inefficiencies and take appropriate measures to increase the efficiency of county public hospitals in the three areas of China, especially in Central China.
文摘Although mining production depends on various equipments, significant amount of production loss can be attributed a specific equipment or fleet. Bottleneck is defined not only by production loss but also by our satisfaction from the equipment. The user satisfaction could be measured as machine effectiveness.Mining literatures on performance improvement and optimization of equipment operations assert importance of availability, utilization and production performance as key parameters. These three parameters are useful for evaluating effectiveness of equipment. Mine production index(MPI), which can represent the effect of these factors, has been applied for continuous operation in mining. MPI uses Fuzzy Delphi Analytical Hierarchy Process to determine importance of each three parameter for individual equipment. A case study in a Swedish open pit mine was done to evaluate the field application of MPI.The results reveal that crusher is the bottleneck equipment in studied mine. As a methodical approach,an algorithm which uses MPI and detects bottleneck in continuous mining operation has been proposed.
基金Under the auspices of Key Program of Chinese Academy of Sciences(No.KZZD-EW-08-02)CAS/SAFEA(Chinese Academy of Science/State Administration of Foreign Experts Affairs)International Partnership Program for Creative Research Teams(No.KZZD-EW-TZ-07)Strategic Frontier Program of Chinese Academy of Sciences-Climate Change:Carbon Budget and Relevant Issues(No.XDA05050101)
文摘Forest net primary productivity (NPP) is a key parameter for forest monitoring and management. In this study, monthly and annual forest NPP in the northeastern China from 1982 to 2010 were simulated by using Carnegie-Ames-Stanford Approach (CASA) model with normalized difference vegetation index (NDVI) sequences derived from Advanced Very High Resolution Radiometer (AVHRR) Global Invento y Modeling and Mapping Studies (GIMMS) and Terra Moderate Resolution Imaging Spectroradiometer (MODIS) products. To address the problem of data inconsistency between AVHRR and MODIS data, a per-pixel unary linear regres- sion model based on least ~;quares method was developed to derive the monthly NDVI sequences. Results suggest that estimated forest NPP has mean relative error of 18.97% compared to observed NPP from forest inventory. Forest NPP in the northeastern China in- creased significantly during the twenty-nine years. The results of seasonal dynamic show that more clear increasing trend of forest NPP occurred in spring and awmnn. This study also examined the relationship between forest NPP and its driving forces including the climatic and anthropogenic factors. In spring and winter, temperature played the most pivotal role in forest NPR In autumn, precipitation acted as the most importanl factor affecting forest NPP, while solar radiation played the most important role in the summer. Evaportran- spiration had a close correlation with NPP for coniferous forest, mixed coniferous broadleaved forest, and broadleaved deciduous forest. Spatially, forest NPP in the Da Hinggan Mountains was more sensitive to climatic changes than in the other ecological functional re- gions. In addition to climalie change, the degradation and improvement of forests had important effects on forest NPP. Results in this study are helpful for understanding the regional carbon sequestration and can enrich the cases for the monitoring of vegetation during long time series.
基金Supported by Special Fund for Technology Development of Hainan Scientific Research Institute(KYYS-2019-04)Natural Science Foundation of Hainan Province(318MS109)+1 种基金Special Fund for Construction of China Agricultural Industry Research System(CARS-43-42)Special Funds for Local Science and Technology Development Guided by the Central Committee(ZY2019HN01)
文摘[Objective]The paper was to investigate the effects of dietary crude fiber level on production performance,organ index and serum biochemical parameters of Dingan geese aged from 1 to 28 days.[Method]A total of 144 1-day-old Dingan geese with the same genetic background and similar initial weight(88.75±0.21g)were randomly assigned into 3 groups with 4 replicates per group and 12 geese per replicate,and fed with the diets containing 2.56%,3.52% and 4.48% crude fiber,respectively.The trial lasted 28 d.[Result]1)The final weight and daily gain of 3.52% CF group were significantly higher than those of 2.56% CF group(P<0.05);the feed/gain ratio was markedly lower than that of 2.56% CF group(P<0.05).2)The slaughter rate,semi-eviscerated rate and leg muscle rate of 3.52% CF group were higher than those of 2.56% and 4.48% CF groups(P>0.05).3)As the dietary crude fiber levels rose,the abdominal fat rate showed a downward trend(P>0.05).4)The liver index of 3.52% CF group was significantly higher than that of 2.56% CF group(P<0.05).4)Compared with 2.5%and 4.48% CF groups,the serum albumin concentrations of 3.52% CF group markedly increased(P<0.05),the serum total protein and globin contents were higher(P>0.05),but the serum uric acid level was lower(P>0.05).[Conclusion]When the crude fiber level was 3.52%,the production performances of Dingan geese aged from 1 to 28 days were better,and the liver index and serum albumin level could be obviously improved.
基金Under the auspices of National Key Research and Development Program of China(No.2016YFB0501501,2017YFB0504000)National Natural Science Foundation of China(No.41401110,31400393)
文摘Drought, as a recurring extreme climate event, affects the structure, function, and process of terrestrial ecosystems. Despite the increasing occurrence and intensity of the drought in the past decade in Southwestern China, the impacts of continuous drought events on vegetation in this region remain unclear. During 2001–2012, Southwestern China experienced the severe drought events from 2009 to 2011. Our aim is to characterize drought conditions in the Southwestern China and explore the impacts on the vegetation condition and terrestrial ecosystem productivity. The Standardized Precipitation Index(SPI) was used to characterize drought area and intensity and a light-use efficiency model was used to explore the effect of drought on the terrestrial ecosystem productivity with Moderate Resolution Imaging Spectrometer(MODIS) data. The SPI captured the major drought events in Southwestern China during the study period, indicated that the 12-year period of this study included both ‘normal' precipitation years and two severe drought events in 2009–2010 and 2011. Results showed that vegetation greenness(Normalized Difference Vegetation Index, NDVI and Enhanced Vegetation Index, EVI) both declined in 2009/2010 drought, but the 2011 drought resulted in less declines of vegetation greenness and productivity due to shorten drought duration and rising temperature. Meanwhile, it was about 5 months lapse between drought events and maximum declines in vegetation greenness for 2009/2010 drought events. In addition, forest, grassland and cropland revealed significant different ecosystem responses to drought. It indicated that grassland showed an early sensitivity to drought, while cropland was the most sensitive to water deficit and forest was more resilient to drought. This study suggests that it is necessary to detect the difference responses of ecosystem to drought in a regional area with satellite data and ecosystem model.
基金Under the auspices of MOE(Ministry of Education in China)Project of Humanities and Social Sciences(No.20YJC840027)Natural Science Basic Research Program of Shaanxi,China(No.2021JQ-771,No.2021JQ-768)Soft Science Project of Xi’an Science and Technology Bureau,Shaanxi Province(No.2021-0013)。
文摘With global warming, the great changes in the patterns of plant growth have occurred. The conditions in early spring and late autumn have changed the process of vegetation photosynthesis, which are expected to have a significant impact on net primary productivity(NPP) and affect the global carbon cycle. Currently, the seasonal response characteristics of NPP to phenological changes in dryland ecosystems are still not well defined. This article calibrated and analyzed the normalized difference vegetation index(NDVI)time series of Advanced Very-High-Resolution Radiometer(AVHRR) data from 1982 to 2015 in the Loess Plateau, China. The spatial and temporal distributions of vegetation phenology and NPP in the Loess Plateau under semihumid and semiarid conditions were investigated. The seasonal variation in the NPP response to vegetation phenology under the climate change was also analyzed. The results showed that, different from the northern forest, there was distinct spatial heterogeneity in the effect of climate change on the dynamic change in vegetation growth in the Loess Plateau: 1) an advance of the start of the growing season(SOS) and a delay of the end of the growing season(EOS) significantly increased the NPP in spring and autumn, respectively, in the humid southeast;2) in the arid northwest, the NPP did not significantly increase in spring and autumn but significantly decreased in summer.
基金Supported by Key Research and Development Program of Hebei Province(18226603D)Modern Agricultural Science and Technology Innovation Project of Hebei Province(4-04-03)
文摘In order to study the effects of replacing different proportions of silage maize with silage sweet sorghum treated by different fermentation methods on the production performance and blood biochemical indexes of dairy cows,25 Chinese Holstein lactating cows were randomly divided into 5 groups,5 in each group.The control check (CK) was fed the basal diet;for the experimental group 1 and the experimental group 2,50% of the silage maize in the basal diet was replaced with the additive silage sweet sorghum and the conventional silage sweet sorghum,respectively;and as to the experimental group 3 and the experimental group 4,all the silage maize in the basal diet was replaced with additive silage sweet sorghum and conventional silage sweet sorghum,respectively.The preliminary trial period was 7 d,and the trial period was 35 d.The results showed that the experimental group 1 and the experimental group 3 had the dry matter intake significantly higher than that of the experimental group 2,the experimental group 4 and the CK ( P <0.05).The daily milk yields of the experimental group 1 and the experimental group 2 were significantly lower than that of the CK ( P <0.05),and the experimental group 3 and the experimental group 4 were significantly lower than the experimental group 1 and the experimental group 2 ( P <0.05).The milk protein percentage of the experimental group 2 was extremely significantly higher than that of the experimental group 4 ( P <0.01).The experimental group 1,the experimental group 2 and the experimental group 3 showed the blood glucose levels extremely significantly higher than that in the CK ( P <0.01).The blood urea nitrogen contents in the experimental group 2 and the experimental group 4 were significantly higher than those in the experimental group 1 and the CK ( P <0.01).There were no significant differences in other blood biochemical indexes between various groups ( P >0.05).It is feasible to use silage sweet sorghum to feed dairy cows,but the proportion should not be too large,and attention should be paid to the energy and nitrogen balance of the diet.