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The Correlation between the Power Quality Indicators and Entropy Production Characteristics of Wind Power+Energy Storage Systems
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作者 Caifeng Wen Boxin Zhang +3 位作者 Yuanjun Dai Wenxin Wang Wanbing Xie Qian Du 《Energy Engineering》 EI 2024年第10期2961-2979,共19页
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
关键词 Wind power system entropy production system losses power quality indexes battery energy storage
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Production Chain Length and PPI-CPI Divergence:Analysis Based on the Global Input-output Price Model
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作者 Ni Hongfu Yan Bingqian Wu Liyuan 《China Economist》 2024年第3期49-69,共21页
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
关键词 Global value chains length of production chains consumer price index producer price index
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Dynamic Prediction Method of Production Logistics Bottleneck Based on Bottleneck Index 被引量:22
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作者 LIU Mingzhou TANG Juan GE Maogen JIANG Zengqiang HU Jing LING Lin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期710-716,共7页
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
关键词 production logistics bottleneck shifting quality assurance capability bottleneck index prediction model
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Mine production index(MPI)-extension of OEE for bottleneck detection in mining 被引量:2
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作者 Amol Arun Lanke Seyed Hadi Hoseinie Behzad Ghodrati 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期753-760,共8页
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
关键词 Mine production index Bottleneck seeking FDAHP production analysis
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Radiative dryness index and potential productivity of vegetation in China 被引量:2
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作者 Zhang Xinshi (Chang Hsin-shih) and Yang DiananInstitute of Botany,Chinese Academy of Sciences,Beijing 100044,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1990年第4期95-109,共15页
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
关键词 Chikugo Model radiative dryness index net primary productivity.
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Effects of Crude Fiber Levels on Production Performance, Organ Index and Serum Biochemical Parameters of Dingan Geese Aged from 1 to 28 Days 被引量:1
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作者 Liu Quanwei Wei Limin +5 位作者 Wang Feng Lin Dajie Xing Manping Yang Shaoxiong Sun Ruiping Ye Baoguo 《Animal Husbandry and Feed Science》 CAS 2019年第3期98-102,共5页
[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
关键词 CRUDE fiber Dingan GEESE production performance ORGAN index SERUM BIOCHEMICAL index
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Measuring Scientific Productivity in China Using Malmquist Productivity Index 被引量:1
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作者 Yaoyao Song Torben Schubert +1 位作者 Huihui Liu Guoliang Yang 《Journal of Data and Information Science》 CSCD 2019年第1期32-59,共28页
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
关键词 Data Envelopment Analysis (DEA) Chinese higher education Scientific productivity Malmquist productivity index(MPI)
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Effects of Replacing Maize Silage with Silage Sweet Sorghum on Milk Production and Blood Biochemical Indexes of Dairy Cows 被引量:1
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作者 Siwei WANG Kuiying LI +2 位作者 Shaoqing SHI Feng ZHANG Kun WANG 《Agricultural Biotechnology》 CAS 2019年第3期87-91,共5页
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
关键词 SILAGE sweet SORGHUM SILAGE maize Additive production performance BLOOD biochemical index HOLSTEIN COW
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Reducing Sharp Fluctuations in Body Temperature and Optimizing Production Index of Broilers Using Dietary Electrolytes 被引量:1
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作者 Ibukun Olukorede Popoola Oluwabukola Rashidat Popoola +2 位作者 Oluwaseyi Olamide Olajide Akinyemi Alaba Adeyemi Queenesther Tolu Alegbejo 《Open Journal of Animal Sciences》 2020年第2期266-277,共12页
A degree centigrade fall or rise in body temperature of broiler chickens is sufficient to reduce performance, alter sound physiological state and divert nutritional metabolism in quest for ensuring thermal balance. Th... A degree centigrade fall or rise in body temperature of broiler chickens is sufficient to reduce performance, alter sound physiological state and divert nutritional metabolism in quest for ensuring thermal balance. Thermoregulatory mechanisms of newly hatched chicks are poorly developed, and fluctuations in brooding temperature coupled with severe environmental temperatures in the tropics could threaten the survivability, production and economic integrity of fast-growing strains of broilers. However, information on the effect of sharp fluctuations in body temperature on nutrient intake and European production index (EPI) of broilers fed dietary electrolytes is scanty and thus investigated. Using a total of 300, one-day-old unsexed broiler chicks (Arbor Acre) that were randomly allotted to six dietary treatments (T1-210, T2-240, T3270, T4-300, T5-330 and T6-360 mEq/kg electrolyte balance), data on performance characteristics and their correlations with body temperature and EPI at prestarter, starter and finisher phases were determined using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. At prestarter phase, feed intake (FI) had a strong and positive relationship with protein intake (r = 1.00;p < 0.01), EPI (r = 0.96;p < 0.01) and potassium (K) intake (r = 0.66;p < 0.01), but was negatively correlated with temperature change (r = ?0.39;p < 0.05). However, FI was not significantly correlated with body weight (BW), body weight gain (BWG), sodium (Na) and water intake. At starter phase, EPI was positively correlated to K intake (r = 0.38;p < 0.05), but not Na and chloride (Cl) intake. European production index of starter chicks could be enhanced by increasing the level of K intake through dietary supplementation up to 1.02%. Weight gain was adversely affected by sharp changes in temperature at finisher phase. Increase in water intake may not be a remedial tool in lowering sharp fluctuations in body temperature. However, sharp fluctuation in body temperature of broilers was reduced with DEB of 330, 270 and 240 mEq/kg at prestarter, starter and finisher phases, respectively. 展开更多
关键词 Temperature Change BROILERS European productION index DIETARY Electrolyte Balance Heat Stress
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Assessing Total Factor Productivity for Soybean Production in China Based on DEA-Malmquist Index: 2005-2017
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作者 Shuguo Yang Jaime Malaga Xiangyu Guo 《American Journal of Plant Sciences》 2020年第1期24-39,共16页
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
关键词 Total Factor productIVITY (TFP) SOYBEAN DEA-MALMQUIST index
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Financial Innovation Way of Avoiding Risk of Climate Disasters in Food Production:Weather Index Insurance
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作者 Wei Junying 《Meteorological and Environmental Research》 CAS 2015年第5期24-26,共3页
Climate change will lead to a variety of climate disasters, and climate disasters have a greater impact on China's food production. Weather index insurance is a new financial way to avoid risk of climate disasters ef... Climate change will lead to a variety of climate disasters, and climate disasters have a greater impact on China's food production. Weather index insurance is a new financial way to avoid risk of climate disasters effectively in China's food production. Firstly, the relationship between weather index insurance and food production in China was elaborated, and then the development status, advantages and disadvantages of weather index insurance in China at present were analyzed. Finally, some countermeasures against the problems of weather index insurance in China were put forward. 展开更多
关键词 Weather index insurance Food production Risk aversion Climatic damage China
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Feasibility Analysis of Agricultural Product Price Index Insurance Based on Pilot Cases
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作者 Jianqiang XIE Chunjie QI 《Asian Agricultural Research》 2016年第11期1-4,8,共5页
Agricultural product price index insurance is a kind of index insurance. It avoids defects of traditional agricultural insurance,such as moral hazards,adverse selection,and high management cost. On the basis of studyi... Agricultural product price index insurance is a kind of index insurance. It avoids defects of traditional agricultural insurance,such as moral hazards,adverse selection,and high management cost. On the basis of studying agricultural product price index insurance of all areas of China,this paper analyzed characteristics of agricultural product price index insurance from object selection,product object,premium design,and policy support,and discussed feasibility of extending agricultural product price index insurance in an all-round way. 展开更多
关键词 Price index Agricultural product price index insurance Market risk Pilot application FEASIBILITY
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Productivity Growth in the Transportation Industries in the United States: An Application of the DEA Malmquist Productivity Index
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作者 Jaesung Choi David C. Roberts EunSu Lee 《American Journal of Operations Research》 2015年第1期1-20,共20页
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
关键词 DEA MALMQUIST productIVITY index productIVITY Growth U.S. TRANSPORTATION Industry
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Assessing economic performance of the three major urban agglomerations in China by using Malmquist productivity index
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作者 LI Qiu-ying 《Ecological Economy》 2019年第3期162-167,共6页
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
关键词 ECONOMIC performance THREE MAJOR urban agglomerations MALMQUIST productIVITY index
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An Empirical Assessment of the Impact of Nigerian all Share Index, Market Capitalization, and Number of Equities on Gross Domestic Product
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作者 Obubu Maxwell Obiora-Ilouno Happiness +1 位作者 Uzuke Chinwendu Alice Ikediuwa Udoka Chinedu 《Open Journal of Statistics》 2018年第3期584-602,共19页
A stock exchange is an exchange where stock brokers and traders can buy and sell shares of stock, bonds, and other securities. All listings are included in the Nigerian Stock Exchange All Shares index. In terms of mar... A stock exchange is an exchange where stock brokers and traders can buy and sell shares of stock, bonds, and other securities. All listings are included in the Nigerian Stock Exchange All Shares index. In terms of market capitalization, the Nigerian Stock Exchange is the third largest stock exchange in Africa. Objectives: The paper assesses the impact of Nigerian Stock Market (all share index, market capitalization, and number of equities) on Gross domestic product (Economic Growth). Materials and Methods: Regression analysis and ordinary least square technique were employed. Result and Discussion: The series was stationary at 1%, 5%, and 10% α level;the residuals were normally distributed but not serially correlated at 5% α level. All Share Index, Market Capitalization and Total Number of listed Equities have a joint and individual significant effect on Economic Growth (Gross Domestic Product) with Total Number of listed Equities having a negative (opposite) linear relationship with the Gross Domestic Product. The Durbin-Watson statistics (R2 = 0.9910 = 1.3686) suggest that the model is not spurious and it is devoid of positive and negative autocorrelation (DW = 1.3686 > dl = 1.07 and DW = 1.5033 ?-?du = 2.17). Therefore, it can produce meaningful result when used for forecasting a positive relationship between gross domestic product, all share index and market capitalization with a 99.1% R-square value. Significant Positive connection between all share index, market capitalization, the number of equities and gross domestic product suggests that government policies and bills aimed towards rapid development of the capital market should be initiated. 展开更多
关键词 NIGERIAN Stock MARKET Gross Domestic product MARKET Capitalization ALL SHARE index Augmented Dickey-Fuller TEST Breusch-Godfrey TEST Serial Correlation Lm TEST
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A comparative analysis of Japanese firm productivity: Solow residual and Malmquist productivity index
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作者 Masaru Ichihashi Hidemichi Fujii 《Chinese Business Review》 2009年第6期26-36,共11页
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
关键词 Total Factor productivity Solow residual data envelopment analysis Malmquist productivity index Japanese manufacturing firms
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Overall profit Malmquist productivity index under data uncertainty
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作者 Dariush Akbarian 《Financial Innovation》 2020年第1期109-128,共20页
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
关键词 Data envelopment analysis Imprecise data Profit Malmquist productivity index
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Model development to estimate site index values for six major tree species in North Korea
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作者 Sohee Park A-Ram Yang +1 位作者 Eun-hee Kim Joongbin Lim 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期387-400,共14页
Due to considerable deforestation in North Korea,there is a need to plan forest restoration programs based on scientific forest management.In this study,a methodology was developed for estimating the site index values... Due to considerable deforestation in North Korea,there is a need to plan forest restoration programs based on scientific forest management.In this study,a methodology was developed for estimating the site index values of six major tree species and the forest productivity potential.The site index values of these tree species were derived in South Korea using the Chapman-Richards equation.These values were used with data from the 6th National Forest Inventory,which included 20 types of edaphic,topographic,and climatic factors,and random forest analysis—a widely used machine learning technique for spatial prediction—to develop a new model for estimating the site index values of these species across South Korea.The prediction accuracy of this model was evaluated using the root mean square error.The results show that the prediction accuracy was high,with a root mean square error of~1m.Moreover,the importance of the variables related to climate and geography was generally high.The proposed site index estimation model for six tree species was applied across North Korea,and its effectiveness tested by comparing the estimated values with those reported in literature from North Korea.The differences between the model outputs and recorded data in the northern alpine regions were presumably due to the lack of data for high-altitude regions in South Korea.This model is based on the determination of the suitability of tree species in restoration efforts.Therefore,it can contribute to the evaluation of forest productivity in North Korea and may help plan efficient forest restoration programs. 展开更多
关键词 Environmental factors Forest productivity Machine learning North Korea Random forest Site index
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Major Power Production Indexes Realized in 1996 July
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《Electricity》 1996年第4期54-54,共1页
关键词 Major Power production indexes Realized in 1996 July
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Estimating the Three-Stage Cost Malmquist Productivity Index in the Taiwan Biotech and Biopharmaceutical Industry
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作者 Sheng Tzu-Chun Liu Kai-Ping Yang Yung-Lieh 《Journal of Modern Accounting and Auditing》 2012年第5期679-687,共9页
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
关键词 cost Malmquist productivity index Taiwan biotech and biopharmaceutical (B&BP) industry
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