Agriculture is the basic industry of China and the support of all other industries. In order to clarify the impact of urbanization on China's agriculture, a cointegration test was conducted between the urbanization r...Agriculture is the basic industry of China and the support of all other industries. In order to clarify the impact of urbanization on China's agriculture, a cointegration test was conducted between the urbanization rate and the total agricultural output value in China during the past 30 years of 1986-2015. The results showed that the development of urbanization and agricultural economy had no severe effect on weakening the agricultural economy in China, while on the contrary, there was a long-term equilibrium relationship between the two, which was only limited to a certain range, and in the future high development of urbanization of China, the development of agricultural economy would face great challenges. Therefore, China should specify cultivated land use, strengthen the supervision standard of land circulation; increase investment in science and technology, improve the efficiency of agricultural output; optimize financial support for agriculture, enhance the enthusiasm of farmers; cultivate new agricultural operators, promote the process of agricultural industrialization, so as to form economies of scale and explore a new road of urbanization which is not at the expense of the cost of agricultural economy.展开更多
The research infrastructure is very crucial for the development of some fundamental research. However,it is costly to buy,install and operate the infrastructure. This paper analyzes the costs and benefits of research ...The research infrastructure is very crucial for the development of some fundamental research. However,it is costly to buy,install and operate the infrastructure. This paper analyzes the costs and benefits of research infrastructure using a concept termed as investment reliability. Both the costs and the outputs are represented by a cash flow diagram,and the investment reliability is modeled. Different types of outputs are taken into concern in the model formulation. Illustrative examples are proposed to show how to apply the model.展开更多
Through analyzing the harvested area,yield and total production of natural rubber and the exports of dry rubber,the situation of rubber cultivation in Indonesia was studied,and the development prospects of natural rub...Through analyzing the harvested area,yield and total production of natural rubber and the exports of dry rubber,the situation of rubber cultivation in Indonesia was studied,and the development prospects of natural rubber in Indonesia were explored. The results showed that the harvested area of natural rubber in Indonesia showed a wave-like rise from 1980 to 2016. The area harvested in 2000 was increased by47. 06% compared with that in 1980,and the area harvested in 2016 was increased by 6. 43% compared with that in 2008. The yield of natural rubber in Indonesia showed a dynamic trend from 1980 to 2016. It reached the maximum( 993 kg/ha) in 2007 and reached the minimum( 575 kg/ha) in 1982. The total production of natural rubber in Indonesia showed a wave-like rise during 1980-2016. The total production of natural rubber in 2000 was increased by 47. 06% compared with that in 1980,and the total production of natural rubber in 2016 was increased by 110. 67% compared with that in 2000. The export volume of dry natural rubber in Indonesia basically showed a concussive rise from 1980 to 2016. The proportion of export volume in the total production in 2016 declined by 14. 75% compared with that in 1980. It is believed that the harvested area of natural rubber in Indonesia will be near the peak in the next few years,and it is difficult to increase the output; the proportion of exported natural rubber in the total production will decline slowly; and the potential for natural rubber development is large.展开更多
To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a ...To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a multi-stage robust optimal control method,which helps overcome the limitations of traditional methods in terms of time scale.The goal is to effectively utilize the energy storage power station system to address issues caused by unpredictable variations in environmental energy and fluctuating load throughout the day.To achieve this,a mathematical model is constructed to represent uncertain energy sources such as photovoltaic and wind power.The generalized Benders Decomposition method is then employed to solve the multi-stage objective optimization problem.By decomposing the problem into a series of sub-objectives,the system scale is effectively reduced,and the algorithm’s convergence ability is improved.Compared with other algorithms,the multi-stage robust optimization model has better economy and convergence ability and can be used to guide the power dispatching of uncertain energy and energy storage systems.展开更多
The world economy is crossing the period of Great Transformations and transition towards a New World Order,dominated by the increasing role of China in the world,given the fast implementation of the technological prog...The world economy is crossing the period of Great Transformations and transition towards a New World Order,dominated by the increasing role of China in the world,given the fast implementation of the technological progress(Digital and Artificial Intelligence Revolutions).This paper analyses the economic relations between China and Romania and estimates the dynamics of the potential GDP in these states by implementing standard econometric tools.The results point to the upward trend in terms of bilateral trade between China-Romania in the post-pandemic era and emphasize the potential of the development in the mid-run.展开更多
Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-c...Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-cesses in sandstone aquifers.These four parameters reflect the characteristics of pore structure of sandstone from different perspectives,and the traditional empirical formulas cannot make accurate predictions of them due to their complexity and heterogeneity.In this paper,eleven types of sandstone CT images were firstly segmented into numerous subsample images,the porosity,tortuosity,SSA,and permeability of the subsamples were calculated,and the dataset was established.The 3D convolutional neural network(CNN)models were subse-quently established and trained to predict the key reactive transport parameters based on subsample CT images of sandstones.The results demonstrated that the 3D CNN model with multiple outputs exhibited excellent prediction ability for the four parameters compared to the traditional empirical formulas.In particular,for the prediction of tortuosity and permeability,the 3D CNN model with multiple outputs even showed slightly better prediction ability than its single-output variant model.Additionally,it demonstrated good generalization per-formance on sandstone CT images not included in the training dataset.The study showed that the 3D CNN model with multiple outputs has the advantages of simplifying operation and saving computational resources,which has the prospect of popularization and application.展开更多
This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introdu...This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introduces the history and traditional cultivation practices of tea in Suzhou,as well as the current challenges and problems faced by the industry.An in-depth analysis was conducted on the overview and improvement plans of the three-dimensional cultivation mode,covering relevant technical methods.Based on this analysis,the impact of the three-dimensional cultivation on the value of output per acre was studied and predicted.Its potential and advantages were explored and compared with the effectiveness of traditional cultivation models.Additionally,the impact of the three-dimensional cultivation mode on sales was analyzed,examining its market adaptability and competitiveness,as well as its advantages in expanding sales channels and market coverage.The study also focused on the promoting effect of diversified sales models on the Suzhou tea industry,including direct consumption market development,tea processing product development and promotion,and the integration of tea culture and the tourism industry.To ensure sustainable development,the article evaluates the environmental impact,economic feasibility,social benefits,and farmer benefits of the three-dimensional cultivation model.Finally,the prospects for the development of the Suzhou tea industry were discussed,and the positioning and response strategies of the threedimensional cultivation model were proposed.展开更多
To meet the demands for different supply voltage levels on SOC required by digital modules like CPU core and analog modules,a novel dual-output charge pump is proposed. The charge pump can output a step-up and a step-...To meet the demands for different supply voltage levels on SOC required by digital modules like CPU core and analog modules,a novel dual-output charge pump is proposed. The charge pump can output a step-up and a step-down voltage simultaneously with a high driving capability. The multiple gain pair technique was introduced to enhance its efficiency. The proposed co-use technology for capacitors and switch arrays reduced its cost. The charge pump was designed and fabricated in a TSMC 0.35μm mixed-signal CMOS process. A group of analytical equations were derived to model its static characteristics. A state-space model was derived to describe its small-signal dynamic behavior. Analytical predictions were verified by Spectre simulation and testing. The consistency of simulated results as well as test results with analytical predictions demonstrated the high precision of the derived analytical equations and the developed models.展开更多
The researching on the DMUs with undesirable outputs gives the non-radial model FDEA of the relative efficiency evaluation,proves the efficiency theories, and calculates the example.The application of FDEA model shows...The researching on the DMUs with undesirable outputs gives the non-radial model FDEA of the relative efficiency evaluation,proves the efficiency theories, and calculates the example.The application of FDEA model shows its importance in the production to save the resources,improve the desirable outputs, and decrease the undesirable outputs,especially reduce the environmental pollution.展开更多
According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of lab...According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of labor force and land, Nanjing suburban counties have entered into a stage of "high input-high output", considering no matter from agricultural total value of output or from agricultural added value. In future, structure configuration of agricultural input factors should be optimized in Nanjing suburban counties by technology input to improve agricultural technology and technical efficiency in order to further achieve sustainable development of agriculture.展开更多
An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential pha...An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential phase shift and correlation coefficients between the horizontal and vertical polarization signals at zero lag can be derived from rain, snow and hail contents of numerical model outputs. Effects of environmental temperature and the melting process on polarimetric variables are considered in the algorithm. The algorithm is applied to the Advanced Regional Prediction System (ARPS) model simulation results for a hail storm. The spatial distributions of the derived parameters are reasonable when compared with observational knowledge. This work provides a forward model for assimilation of dual linear polarization radar data into a mesoscale model.展开更多
The background error covariance plays an important role in modern data assimilation and analysis systems by determining the spatial spreading of information in the data. A novel method based on model output is propose...The background error covariance plays an important role in modern data assimilation and analysis systems by determining the spatial spreading of information in the data. A novel method based on model output is proposed to estimate background error covariance for use in Optimum Interpolation. At every model level, anisotropic correlation scales are obtained that give a more detailed description of the spatial correlation structure. Furthermore, the impact of the background field itself is included in the background error covariance. The methodology of the estimation is presented and the structure of the covariance is examined. The results of 20-year assimilation experiments are compared with observations from TOGA-TAO (The Tropical Ocean-Global Atmosphere-Tropical Atmosphere Ocean) array and other analysis data.展开更多
There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by env...There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by environmental pressures. However, recent studies show that necrosis can also be regulated by specific cell signaling pathways. This mode of death, termed necroptosis, has been found to be related to the occurrence and development of many diseases. We used bibliometrics to analyze the global output of literature on necroptosis in the field of neuroscience published in the period 2007–2019 to identify research hotspots and prospects. We included 145 necroptosisrelated publications and 2239 references published in the Web of Science during 2007–2019. Visualization analysis revealed that the number of publications related to necroptosis has increased year by year, reaching a peak in 2019. China is the country with the largest number of publications. Key word and literature analyses demonstrated that mitochondrial function change, stroke, ischemia/reperfusion and neuroinflammation are likely the research hotspots and future directions of necroptosis research in the nervous system. The relationship between immune response-related factors, damage-associated molecular patterns, pathogen-associated molecular patterns and necroptosis may become a potential research hotspot in the future. Taken together, our findings suggest that although the inherent limitations of bibliometrics may affect the accuracy of the literature-based prediction of research hotspots, the results obtained from the included publications can provide a reference for the study of necroptosis in the field of neuroscience.展开更多
Solid phase extraction is widely used in sample pretreatment,concentration and analysis processes due to high selectivity and suitability for low concentration sample system.In this review,we systematically summarized...Solid phase extraction is widely used in sample pretreatment,concentration and analysis processes due to high selectivity and suitability for low concentration sample system.In this review,we systematically summarized and discussed the development trends of solid phase extraction by bibliometrics method.By analyzing papers output scale,the research and development direction of solid phase extraction technology is prospected.We also give an overview on current strategies of novel solid phase extraction from the separation medium and separation technology.The paper aims to describe the global research profile and the development trends of solid phase extraction,to help researchers to accurately grasp the research trend and to provide support for scientific research institutions to formulate scientific policies and strategic plans.Furthermore,the prospect of the development and application of solid phase extraction is also discussed.展开更多
This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient ou...This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given.展开更多
文摘Agriculture is the basic industry of China and the support of all other industries. In order to clarify the impact of urbanization on China's agriculture, a cointegration test was conducted between the urbanization rate and the total agricultural output value in China during the past 30 years of 1986-2015. The results showed that the development of urbanization and agricultural economy had no severe effect on weakening the agricultural economy in China, while on the contrary, there was a long-term equilibrium relationship between the two, which was only limited to a certain range, and in the future high development of urbanization of China, the development of agricultural economy would face great challenges. Therefore, China should specify cultivated land use, strengthen the supervision standard of land circulation; increase investment in science and technology, improve the efficiency of agricultural output; optimize financial support for agriculture, enhance the enthusiasm of farmers; cultivate new agricultural operators, promote the process of agricultural industrialization, so as to form economies of scale and explore a new road of urbanization which is not at the expense of the cost of agricultural economy.
基金Ministry of Education Project,China(No.2014GL15)
文摘The research infrastructure is very crucial for the development of some fundamental research. However,it is costly to buy,install and operate the infrastructure. This paper analyzes the costs and benefits of research infrastructure using a concept termed as investment reliability. Both the costs and the outputs are represented by a cash flow diagram,and the investment reliability is modeled. Different types of outputs are taken into concern in the model formulation. Illustrative examples are proposed to show how to apply the model.
文摘Through analyzing the harvested area,yield and total production of natural rubber and the exports of dry rubber,the situation of rubber cultivation in Indonesia was studied,and the development prospects of natural rubber in Indonesia were explored. The results showed that the harvested area of natural rubber in Indonesia showed a wave-like rise from 1980 to 2016. The area harvested in 2000 was increased by47. 06% compared with that in 1980,and the area harvested in 2016 was increased by 6. 43% compared with that in 2008. The yield of natural rubber in Indonesia showed a dynamic trend from 1980 to 2016. It reached the maximum( 993 kg/ha) in 2007 and reached the minimum( 575 kg/ha) in 1982. The total production of natural rubber in Indonesia showed a wave-like rise during 1980-2016. The total production of natural rubber in 2000 was increased by 47. 06% compared with that in 1980,and the total production of natural rubber in 2016 was increased by 110. 67% compared with that in 2000. The export volume of dry natural rubber in Indonesia basically showed a concussive rise from 1980 to 2016. The proportion of export volume in the total production in 2016 declined by 14. 75% compared with that in 1980. It is believed that the harvested area of natural rubber in Indonesia will be near the peak in the next few years,and it is difficult to increase the output; the proportion of exported natural rubber in the total production will decline slowly; and the potential for natural rubber development is large.
文摘To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a multi-stage robust optimal control method,which helps overcome the limitations of traditional methods in terms of time scale.The goal is to effectively utilize the energy storage power station system to address issues caused by unpredictable variations in environmental energy and fluctuating load throughout the day.To achieve this,a mathematical model is constructed to represent uncertain energy sources such as photovoltaic and wind power.The generalized Benders Decomposition method is then employed to solve the multi-stage objective optimization problem.By decomposing the problem into a series of sub-objectives,the system scale is effectively reduced,and the algorithm’s convergence ability is improved.Compared with other algorithms,the multi-stage robust optimization model has better economy and convergence ability and can be used to guide the power dispatching of uncertain energy and energy storage systems.
文摘The world economy is crossing the period of Great Transformations and transition towards a New World Order,dominated by the increasing role of China in the world,given the fast implementation of the technological progress(Digital and Artificial Intelligence Revolutions).This paper analyses the economic relations between China and Romania and estimates the dynamics of the potential GDP in these states by implementing standard econometric tools.The results point to the upward trend in terms of bilateral trade between China-Romania in the post-pandemic era and emphasize the potential of the development in the mid-run.
基金supported by the National Natural Science Foundation of China (12105139 and 42277264)National Key Research and Development Program of China (2021YFC2902104)Education Department of Hunan Province (21B0446).
文摘Porosity,tortuosity,specific surface area(SSA),and permeability are four key parameters of reactive transport modeling in sandstone,which are important for understanding solute transport and geochemical reaction pro-cesses in sandstone aquifers.These four parameters reflect the characteristics of pore structure of sandstone from different perspectives,and the traditional empirical formulas cannot make accurate predictions of them due to their complexity and heterogeneity.In this paper,eleven types of sandstone CT images were firstly segmented into numerous subsample images,the porosity,tortuosity,SSA,and permeability of the subsamples were calculated,and the dataset was established.The 3D convolutional neural network(CNN)models were subse-quently established and trained to predict the key reactive transport parameters based on subsample CT images of sandstones.The results demonstrated that the 3D CNN model with multiple outputs exhibited excellent prediction ability for the four parameters compared to the traditional empirical formulas.In particular,for the prediction of tortuosity and permeability,the 3D CNN model with multiple outputs even showed slightly better prediction ability than its single-output variant model.Additionally,it demonstrated good generalization per-formance on sandstone CT images not included in the training dataset.The study showed that the 3D CNN model with multiple outputs has the advantages of simplifying operation and saving computational resources,which has the prospect of popularization and application.
基金Suzhou Agricultural Vocational and Technical College Young Teachers Research Ability Enhancement Program“Research and Screening of Bacteria for Fermented Beverages of Vice Tea and Loquat Flower”(Project No.QN[2022]01)。
文摘This article explores the impact of the three-dimensional cultivation mode on the development of the Suzhou tea industry,focusing on the diversified estimation of the value of output per acre and sales mode.It introduces the history and traditional cultivation practices of tea in Suzhou,as well as the current challenges and problems faced by the industry.An in-depth analysis was conducted on the overview and improvement plans of the three-dimensional cultivation mode,covering relevant technical methods.Based on this analysis,the impact of the three-dimensional cultivation on the value of output per acre was studied and predicted.Its potential and advantages were explored and compared with the effectiveness of traditional cultivation models.Additionally,the impact of the three-dimensional cultivation mode on sales was analyzed,examining its market adaptability and competitiveness,as well as its advantages in expanding sales channels and market coverage.The study also focused on the promoting effect of diversified sales models on the Suzhou tea industry,including direct consumption market development,tea processing product development and promotion,and the integration of tea culture and the tourism industry.To ensure sustainable development,the article evaluates the environmental impact,economic feasibility,social benefits,and farmer benefits of the three-dimensional cultivation model.Finally,the prospects for the development of the Suzhou tea industry were discussed,and the positioning and response strategies of the threedimensional cultivation model were proposed.
文摘To meet the demands for different supply voltage levels on SOC required by digital modules like CPU core and analog modules,a novel dual-output charge pump is proposed. The charge pump can output a step-up and a step-down voltage simultaneously with a high driving capability. The multiple gain pair technique was introduced to enhance its efficiency. The proposed co-use technology for capacitors and switch arrays reduced its cost. The charge pump was designed and fabricated in a TSMC 0.35μm mixed-signal CMOS process. A group of analytical equations were derived to model its static characteristics. A state-space model was derived to describe its small-signal dynamic behavior. Analytical predictions were verified by Spectre simulation and testing. The consistency of simulated results as well as test results with analytical predictions demonstrated the high precision of the derived analytical equations and the developed models.
文摘The researching on the DMUs with undesirable outputs gives the non-radial model FDEA of the relative efficiency evaluation,proves the efficiency theories, and calculates the example.The application of FDEA model shows its importance in the production to save the resources,improve the desirable outputs, and decrease the undesirable outputs,especially reduce the environmental pollution.
文摘According to data in Nanjing Statistical Yearbook, contribution made by agricultural production factors was analyzed with contribution models of agricultural factors and the results showed that with restriction of labor force and land, Nanjing suburban counties have entered into a stage of "high input-high output", considering no matter from agricultural total value of output or from agricultural added value. In future, structure configuration of agricultural input factors should be optimized in Nanjing suburban counties by technology input to improve agricultural technology and technical efficiency in order to further achieve sustainable development of agriculture.
文摘An algorithm for retrieving polarimetric variables from numerical model fields is developed. By using this technique, radar reflectivity at horizontal polarization~ differential reflectivity, specific differential phase shift and correlation coefficients between the horizontal and vertical polarization signals at zero lag can be derived from rain, snow and hail contents of numerical model outputs. Effects of environmental temperature and the melting process on polarimetric variables are considered in the algorithm. The algorithm is applied to the Advanced Regional Prediction System (ARPS) model simulation results for a hail storm. The spatial distributions of the derived parameters are reasonable when compared with observational knowledge. This work provides a forward model for assimilation of dual linear polarization radar data into a mesoscale model.
基金supported by the National Key Program for Developing Basic Sciences(G1999032801)the National Natural Science Foundation of China(Grant No.40005007,40233033,and 40221503)
文摘The background error covariance plays an important role in modern data assimilation and analysis systems by determining the spatial spreading of information in the data. A novel method based on model output is proposed to estimate background error covariance for use in Optimum Interpolation. At every model level, anisotropic correlation scales are obtained that give a more detailed description of the spatial correlation structure. Furthermore, the impact of the background field itself is included in the background error covariance. The methodology of the estimation is presented and the structure of the covariance is examined. The results of 20-year assimilation experiments are compared with observations from TOGA-TAO (The Tropical Ocean-Global Atmosphere-Tropical Atmosphere Ocean) array and other analysis data.
基金supported by the National Natural Science Foundation of China,Nos. 81772134,81971891,and 81571939 (to KX)the Key Research and Development Program of Hunan Province of China,No. 2018SK2091 (to KX)+3 种基金Hunan Provincial Innovation Foundation For Postgraduate,No. CX20200116 (to WTY)Wu Jie Ping Medical Foundation of the Minister of Health of China,No. 320.6750.14118 (to KX)Foundation of Science and Technology of Hunan Province of China,No. 2018JJ2552 (to YC)the Project of Graduate Independent Exploration and Innovation Plan of Central South University of China,No. 2020zzts218 (to WTY)。
文摘There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by environmental pressures. However, recent studies show that necrosis can also be regulated by specific cell signaling pathways. This mode of death, termed necroptosis, has been found to be related to the occurrence and development of many diseases. We used bibliometrics to analyze the global output of literature on necroptosis in the field of neuroscience published in the period 2007–2019 to identify research hotspots and prospects. We included 145 necroptosisrelated publications and 2239 references published in the Web of Science during 2007–2019. Visualization analysis revealed that the number of publications related to necroptosis has increased year by year, reaching a peak in 2019. China is the country with the largest number of publications. Key word and literature analyses demonstrated that mitochondrial function change, stroke, ischemia/reperfusion and neuroinflammation are likely the research hotspots and future directions of necroptosis research in the nervous system. The relationship between immune response-related factors, damage-associated molecular patterns, pathogen-associated molecular patterns and necroptosis may become a potential research hotspot in the future. Taken together, our findings suggest that although the inherent limitations of bibliometrics may affect the accuracy of the literature-based prediction of research hotspots, the results obtained from the included publications can provide a reference for the study of necroptosis in the field of neuroscience.
基金financial support of the Natural Science Foundation of Beijing (2194086)the National Natural Science Foundation of China (Nos. 21922814, 21676273, 21961160745, 31961133019 and 21921005)
文摘Solid phase extraction is widely used in sample pretreatment,concentration and analysis processes due to high selectivity and suitability for low concentration sample system.In this review,we systematically summarized and discussed the development trends of solid phase extraction by bibliometrics method.By analyzing papers output scale,the research and development direction of solid phase extraction technology is prospected.We also give an overview on current strategies of novel solid phase extraction from the separation medium and separation technology.The paper aims to describe the global research profile and the development trends of solid phase extraction,to help researchers to accurately grasp the research trend and to provide support for scientific research institutions to formulate scientific policies and strategic plans.Furthermore,the prospect of the development and application of solid phase extraction is also discussed.
基金supported by the Research Start Funds for Introducing High-level Talents of North China University of Water Resources and Electric Power
文摘This paper expresses the efficient outputs of decisionmaking unit(DMU) as the sum of "average outputs" forecasted by a GM(1,N) model and "increased outputs" which reflect the difficulty to realize efficient outputs.The increased outputs are solved by linear programming using data envelopment analysis efficiency theories,wherein a new sample is introduced whose inputs are equal to the budget in the issue No.n + 1 and outputs are forecasted by the GM(1,N) model.The shortcoming in the existing methods that the forecasted efficient outputs may be less than the possible actual outputs according to developing trends of input-output rate in the periods of pre-n is overcome.The new prediction method provides decision-makers with more decisionmaking information,and the initial conditions are easy to be given.