Rehabilitation robots can help physiatrists to assist patients in improving their movement ability.Due to the interaction between rehabilitation robots and patients,the robots need to complete rehabilitation training ...Rehabilitation robots can help physiatrists to assist patients in improving their movement ability.Due to the interaction between rehabilitation robots and patients,the robots need to complete rehabilitation training on a safe basis.This paper presents an approach for smooth trajectory planning for a cable-driven parallel waist rehabilitation robot(CDPWRR)based on the rehabilitation evaluation factors.First,motion capture technology is used to collect the motion data of several volunteers in waist twisting.Considering the impact of motion variability,the feature points at the center of the human pelvis are obtained after eliminating unreasonable data through rationality judgments.Then,point-to-point waist training trajectory planning based on quintic polynomial and cycloid functions,and multipoint waist training trajectory planning based on quintic B-spline functions are carried out.The corresponding planned curves and kinematics characteristics using three methods are compared and analyzed.Subsequently,the rehabilitation evaluation factors are introduced to conduct smooth trajectory planning for waist training,and the waist trajectory with better compliance is obtained based on the safety and feasibility of waist motion.Finally,the physical prototype of the CDPWRR is built,and the feasibility and effectiveness of the proposed smooth trajectory planning method are proved by numerical analysis and experiments.展开更多
The 30 pairs of feed and dung samples from the livestock and poultry farms with different scales were checked and analyzed. The results showed: a great linear relation existed between the feed factors and 7 pollutant...The 30 pairs of feed and dung samples from the livestock and poultry farms with different scales were checked and analyzed. The results showed: a great linear relation existed between the feed factors and 7 pollutants such as ammonia nitrogen, phosphorus, copper, iron, arsenic, mercury, cadmium in livestock and poultry's dung. The main affecting factors of feed were respectively nitrogen, phosphorus, copper, and arsenic, which were totally feed ingredient elements. And it indicated that the dung pollutants such as nitrogen, phosphorus, copper, iron, arsenic, mercury, and cadmium could be regulated by controlling the feed ingredients. But the dung nitrogen did not have a linear relation with the feed factors. Reducing the nitrogen in feed did not mean the relative decrease of the dung nitrogen content. Feed consumption rate of unit weight did not have notable performances, and it did not show curve model after curve fitting method. The pollutant index of ammonia nitrogen, phosphorus, copper, and arsenic of the group whose feed consumption rate of unit weight was less than 20 g/kg·d was extremely remarkably lower than those of the 20 -30 g/kg·d group. The pollutant index of mercury, chromium, and cadmium showed the opposite performance. With the increase of feed consumption rate, each pollutant did not act in an increasing trend, of which the pollutant index of ammonia nitrogen and the general phosphorus presented a quadratic model trend. The feed consumption level of unit weight had an extremely remarkable effect on the pollution level rate and the eady warning level rate, showing the thrice model trend, of which the 20 -30 g/kg. d group was the maximal, respectively for 16.67% and 50%, which was the same with the above-mentioned law.展开更多
The growth of tobacco is sensitive to environment conditions. The tobacco production is strictly restricted by regional cultivated land. Based on the principal of hiberarchy analysis and fuzzy mathematics and the tech...The growth of tobacco is sensitive to environment conditions. The tobacco production is strictly restricted by regional cultivated land. Based on the principal of hiberarchy analysis and fuzzy mathematics and the technique of geographic information system (GIS), the comprehensive evaluation of tobacco ecology suitability were studied according to the actual circumstances of the whole Henan tobacco planting regions, China. The evaluation index system of tobacco ecology suitability of Henan tobacco planting regions was established by choosing 17 evaluation indexes from 3 respects of climate, soil and landform with Delphi method. Furthermore, the membership function was set up according to the effects of each ecology factors on the growth and quality of tobacco suitability. And the analytical hierarchy process (AHP) was used to determine the weight of indexes by using quantitative analysis. Then the tobacco ecology suitability map of Henan tobacco plantation was drawn with GIS software mapGIS. It is found that the most areas of the western and southern parts of Henan Province, China, are the highly suitable regions, accounting for 22.52% of Henan tobacco planting areas. It is because that there are medium air temperature, sunshine and rainfall, medium soil pH value, and high contents of soil organic matter in the regions. Moreover, the topography is hill and massif, and the height above sea level is between 150-800 m there. Some areas of the southern and middle parts of Henan Province are the suitable ones, accounting for 34.99% of Henan tobacco planting areas. It is because that there are enough rainfall, medium air temperature, high contents of available N and available K in the soil in these regions. There are less suitable regions in the northern and eastern parts of the investigated regions because of drought, too high pH value and CI in the soil and irrigation water, accounting for 35.54% of the whole areas. It can be conducted rapidly and correctly by combining AHP and membership function for comprehensive evaluation of tobacco ecological suitability supported by GIS. There are above moderate ecological suitability for most part of tobacco planting fields in Henan Province. The distributions of tobacco ecological suitability calculated are identical with actual tobacco productivity completely.展开更多
The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SN...The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.展开更多
Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight d...Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight distribution for operational evaluation was developed, and multiple-forecaster synchronous forecasting was realized while avoiding the instability cased by only one forecaster. Weights were distributed to the forecasters according to each one's forecast precision. An evaluation criterion for the professional level of the forecasters was also built. The eligibility rates of forecast results demonstrate the skill of the forecasters and the stability of their forecasts. With the developed tide forecasting method, the precision and reasonableness of tide forecasting are improved. The application of the present method to tide forecasting at the Huangpu Park tidal station demonstrates the validity of the method.展开更多
In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the compr...In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the comprehensive land price of expropriated area. Reasonable division can help to improve the scientific and applicability of the comprehensive land price of the region. How to maximize the protection of farmers’ rights and interests by the division of land requisition is an urgent problem to be solved. Taking Gongcheng Yao Autonomous County as an example, this study adopted the multi-factor comprehensive evaluation method to evaluate the division of land requisition in this area, and carried out the corresponding spatial analysis and data processing based on GIS technology. Gongcheng Yao Autonomous County was divided into levy areas, and the Delphi method was used to screen the impact factors and determine the weight of the levy areas. Reasonable division of land requisition area can provide references for land requisition area, make it more scientific and reasonable, and protect the rights and interests of farmers.展开更多
This paper introduces concepts related to scientific research achievements, analyzes current evaluation methods with regard to nursing research achievements and their application at home and abroad, and summarizes fin...This paper introduces concepts related to scientific research achievements, analyzes current evaluation methods with regard to nursing research achievements and their application at home and abroad, and summarizes findings from the investigation of obstacles to the application of nursing research results in China, aiming to provide reference points for the evaluation and application of nursing research results in China.展开更多
Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were ana...Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were analyzed by single-factor evaluation method and seasonal Kendall test to evaluate the trophic status of the reservoirs and explore the influencing factors of characteristic pollutants.The results showed that:①the water quality of the reservoirs was good and could meet the water needs of various functions;②the water quality of the reservoirs had generally changed from bad to good in recent years,indicating that the implementation of“river chief system”has achieved certain results;③Kendall test analysis showed that,except for individual projects which showed an upward trend in water quality,other projects showed no obvious change trend or downward trend,indicating that the water quality of the reservoirs is indeed improving;④the causes of water pollution in reservoir area were further analyzed by exploring the natural and human factors of the characteristic pollutant total phosphorus.It is recommended to strengthen supervision in the later stage to control point and non-point source pollution.展开更多
Virtual reality(VR)has been widely used in various manufacturing industries,and VR-based virtual manufacturing has received significant attention in the current intelligent manufacturing era.Digital human models(DHMs)...Virtual reality(VR)has been widely used in various manufacturing industries,and VR-based virtual manufacturing has received significant attention in the current intelligent manufacturing era.Digital human models(DHMs)are essential for virtual manufacturing applications.Additionally,researching new applications of DHMs has developed into an important academic research field.This paper aims to identify the applications and research trends of DHMs in the manufacturing industry and to provide a reference for the continued development of virtual manufacturing and DHMs.We selected a total of 49 related articles from a large number of articles published between 2014 and 2019.The applications of DHMs in the manufacturing industry are analyzed from different perspectives and various relevant technical limitations are discussed.The results indicate that the applications of DHMs differ significantly between different types of fields.The automotive industry is the main application field for DHMs,and assembly/maintenance simulations and evaluations are the main application types.Additionally,there are still some limitations in the establishment of virtual environments,motion control,and DHM evaluation that should be addressed.Finally,research trends in the application of DHMs are illustrated and discussed,including the planning and assessment of human-robot collaboration systems,the combination of DHMs and augmented reality,and improved motion planning for DHMs.In summary,the application of DHMs can improve the realism and effectiveness of virtual manufacturing,and DHMs will be more widely and deeply studied and applied in various manufacturing industries in the near future.展开更多
Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a c...Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a comprehensive therapy for fulminant hepatitis. The following is a report of the results of using pHGF for the treatment of 1687 cases of fulminant hepatitis (with 1196 controls).展开更多
Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuse...Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuses on overseas basins with different exploration degrees and offers a new evaluation system and research method for fast evaluation and risk analysis on hydrocarbon potential.Based on the theory of probability,this new evaluation system evaluates each parameter and core accumulation factor with comprehensive and quantitative assignment,to accelerate geological evaluation.In addition,this paper suggests that source rock evaluation should be the core criterion in screening evaluation of poorexplored basins,and also proposes that both the exploration potential and geological recognition should drive the evaluation for basins with high exploration degrees.This new system and method,which is an effective system for fast basin evaluation,is suggested to be used in oversea evaluation and decision-making objectively,scientifically and efficiently.展开更多
The comprehensive evaluation of the schemes of coal mine design often involves some factors that are difficult to be expressed in quantity and these factors are often described qualitatively.Therefore, it is difficult...The comprehensive evaluation of the schemes of coal mine design often involves some factors that are difficult to be expressed in quantity and these factors are often described qualitatively.Therefore, it is difficult for us to adopt uniformly concrete evaluation value to appraise each design plan. So the subjective view point of the design personnel plays an important role in choosing final plan. Sometime it will lead one sided decision, which will make the chosen scheme not optimized. Thus the quantitative model for evaluating design is set up by means of Fuzzy Mathematics and a concrete calculating example is given in this paper.\;The Fuzzy mathematical model proposed in this paper is good in adaptability and convenience. Both comments and degrees of importance in correspondence with the evaluated factors of each plan can be given qualitatively according to the people′s idiomatic expression by the model. After simple calculation, the quantitative result or comprehensive evaluation value that evaluates each design plan can be obtained,which provides a scientific basis for design personnel to choose the optimum scheme.展开更多
The increasing demand for versatile and high-quality near-field radiative heat transfer(NFRHT) has created a critical need for a design approach that can handle numerous candidate structures. In this work, we employ a...The increasing demand for versatile and high-quality near-field radiative heat transfer(NFRHT) has created a critical need for a design approach that can handle numerous candidate structures. In this work, we employ and develop an adaptive hybrid Bayesian optimization(AHBO) algorithm to design the high-quality quasi-monochromatic NFRHT. The candidate materials include hexagonal boron nitride, silicon carbide, and doped silicon. The high-quality quasi-monochromatic NFRHT is optimized over 1.0 × 10^(8) candidate structures to maximize the evaluation factor. It is worth noting that only 2.6% of the candidate structures needed to be calculated to identify the optimal structure. The optimal structure of quasi-monochromatic NFRHT is an aperiodic multilayer metamaterial that differs from conventional periodic multilayer structures. Moreover, we investigate the robustness and mechanisms of the optimal quasi-monochromatic NFRHT with respect to the vacuum gap distance and the temperature difference between the emitter and receiver. In addition, the high-quality multi-peak NFRHT is designed using the AHBO algorithm by improving the definition of the evaluation factor. The results demonstrate that the AHBO algorithm is efficient in designing high-quality quasi-monochromatic and multi-peak NFRHT, and it can be further expanded to other structural designs in the field of energy conversion.展开更多
The water quality of rivers flowing into lakes is a reflection of the regional environment and significantly contributes to the nutrient levels of the lake.Based on multi-year monitoring data of the estuarine water qu...The water quality of rivers flowing into lakes is a reflection of the regional environment and significantly contributes to the nutrient levels of the lake.Based on multi-year monitoring data of the estuarine water quality of the Zi River which flows into the Dongting Lake,single factor analysis was performed for the dissolved oxygen,nitrogen ammonia(NH3-N),chemical oxygen demand,total phosphorus,permanganate index,and biochemical oxygen demand.The analysis indicated that the estuarine water quality class was dependent on the NH3-N level.The NH3-N trend of the Zi River was then simulated using an improved grey model IGM(0,N)based on a grey correlation analysis.The IGM(0,N)model produced a smaller average relative error and a more accurate prediction compared with a multiple regression model,thus validating the use of the IGM(0,N)model as a suitable method to simulate the estuarine water quality with a complex multi-factor system.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.52205014,51925502)the Fundamental Research Funds for the Central Universities(Grant Nos.JZ2022HGTA0325,JZ2022HGQA0147).
文摘Rehabilitation robots can help physiatrists to assist patients in improving their movement ability.Due to the interaction between rehabilitation robots and patients,the robots need to complete rehabilitation training on a safe basis.This paper presents an approach for smooth trajectory planning for a cable-driven parallel waist rehabilitation robot(CDPWRR)based on the rehabilitation evaluation factors.First,motion capture technology is used to collect the motion data of several volunteers in waist twisting.Considering the impact of motion variability,the feature points at the center of the human pelvis are obtained after eliminating unreasonable data through rationality judgments.Then,point-to-point waist training trajectory planning based on quintic polynomial and cycloid functions,and multipoint waist training trajectory planning based on quintic B-spline functions are carried out.The corresponding planned curves and kinematics characteristics using three methods are compared and analyzed.Subsequently,the rehabilitation evaluation factors are introduced to conduct smooth trajectory planning for waist training,and the waist trajectory with better compliance is obtained based on the safety and feasibility of waist motion.Finally,the physical prototype of the CDPWRR is built,and the feasibility and effectiveness of the proposed smooth trajectory planning method are proved by numerical analysis and experiments.
基金supported by the Scientific Project of Jiangsu Province(DS2007027)
文摘The 30 pairs of feed and dung samples from the livestock and poultry farms with different scales were checked and analyzed. The results showed: a great linear relation existed between the feed factors and 7 pollutants such as ammonia nitrogen, phosphorus, copper, iron, arsenic, mercury, cadmium in livestock and poultry's dung. The main affecting factors of feed were respectively nitrogen, phosphorus, copper, and arsenic, which were totally feed ingredient elements. And it indicated that the dung pollutants such as nitrogen, phosphorus, copper, iron, arsenic, mercury, and cadmium could be regulated by controlling the feed ingredients. But the dung nitrogen did not have a linear relation with the feed factors. Reducing the nitrogen in feed did not mean the relative decrease of the dung nitrogen content. Feed consumption rate of unit weight did not have notable performances, and it did not show curve model after curve fitting method. The pollutant index of ammonia nitrogen, phosphorus, copper, and arsenic of the group whose feed consumption rate of unit weight was less than 20 g/kg·d was extremely remarkably lower than those of the 20 -30 g/kg·d group. The pollutant index of mercury, chromium, and cadmium showed the opposite performance. With the increase of feed consumption rate, each pollutant did not act in an increasing trend, of which the pollutant index of ammonia nitrogen and the general phosphorus presented a quadratic model trend. The feed consumption level of unit weight had an extremely remarkable effect on the pollution level rate and the eady warning level rate, showing the thrice model trend, of which the 20 -30 g/kg. d group was the maximal, respectively for 16.67% and 50%, which was the same with the above-mentioned law.
基金supported by the Major Projectof the National Tobacco Monopoly Bureau, China(110200401021)
文摘The growth of tobacco is sensitive to environment conditions. The tobacco production is strictly restricted by regional cultivated land. Based on the principal of hiberarchy analysis and fuzzy mathematics and the technique of geographic information system (GIS), the comprehensive evaluation of tobacco ecology suitability were studied according to the actual circumstances of the whole Henan tobacco planting regions, China. The evaluation index system of tobacco ecology suitability of Henan tobacco planting regions was established by choosing 17 evaluation indexes from 3 respects of climate, soil and landform with Delphi method. Furthermore, the membership function was set up according to the effects of each ecology factors on the growth and quality of tobacco suitability. And the analytical hierarchy process (AHP) was used to determine the weight of indexes by using quantitative analysis. Then the tobacco ecology suitability map of Henan tobacco plantation was drawn with GIS software mapGIS. It is found that the most areas of the western and southern parts of Henan Province, China, are the highly suitable regions, accounting for 22.52% of Henan tobacco planting areas. It is because that there are medium air temperature, sunshine and rainfall, medium soil pH value, and high contents of soil organic matter in the regions. Moreover, the topography is hill and massif, and the height above sea level is between 150-800 m there. Some areas of the southern and middle parts of Henan Province are the suitable ones, accounting for 34.99% of Henan tobacco planting areas. It is because that there are enough rainfall, medium air temperature, high contents of available N and available K in the soil in these regions. There are less suitable regions in the northern and eastern parts of the investigated regions because of drought, too high pH value and CI in the soil and irrigation water, accounting for 35.54% of the whole areas. It can be conducted rapidly and correctly by combining AHP and membership function for comprehensive evaluation of tobacco ecological suitability supported by GIS. There are above moderate ecological suitability for most part of tobacco planting fields in Henan Province. The distributions of tobacco ecological suitability calculated are identical with actual tobacco productivity completely.
基金supported by the National Natural Science Foundation of China(Grants No.41101250 and 51309031)the Chinese 12th Five-Year Science and Technology Support Program(Grant No.2012BAC06B00)
文摘The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP), which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP), permanganate index (CODM,), dissolved oxygen (DO), and five-day biochemical oxygen demand (BODs), and the concentrations of TP, BODs, ammonia nitrogen (NH3--N), CODM,, DO, and anionic surfactant (Surfa) do not reach the specified standard levels in the tributaries. Seasonal Mann--Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA) results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.
文摘Through analysis of operational evaluation factors for tide forecasting, the relationship between the evaluation factors and the weights of forecasters was examined. A tide forecasting method based on dynamic weight distribution for operational evaluation was developed, and multiple-forecaster synchronous forecasting was realized while avoiding the instability cased by only one forecaster. Weights were distributed to the forecasters according to each one's forecast precision. An evaluation criterion for the professional level of the forecasters was also built. The eligibility rates of forecast results demonstrate the skill of the forecasters and the stability of their forecasts. With the developed tide forecasting method, the precision and reasonableness of tide forecasting are improved. The application of the present method to tide forecasting at the Huangpu Park tidal station demonstrates the validity of the method.
文摘In recent years, with the rapid development of urbanization in China, land acquisition work is particularly important. The division of expropriated area is the primary factor to be considered when evaluating the comprehensive land price of expropriated area. Reasonable division can help to improve the scientific and applicability of the comprehensive land price of the region. How to maximize the protection of farmers’ rights and interests by the division of land requisition is an urgent problem to be solved. Taking Gongcheng Yao Autonomous County as an example, this study adopted the multi-factor comprehensive evaluation method to evaluate the division of land requisition in this area, and carried out the corresponding spatial analysis and data processing based on GIS technology. Gongcheng Yao Autonomous County was divided into levy areas, and the Delphi method was used to screen the impact factors and determine the weight of the levy areas. Reasonable division of land requisition area can provide references for land requisition area, make it more scientific and reasonable, and protect the rights and interests of farmers.
基金supported by Shanxi Province Health Department of scientific and technological projects(No.2013010008)
文摘This paper introduces concepts related to scientific research achievements, analyzes current evaluation methods with regard to nursing research achievements and their application at home and abroad, and summarizes findings from the investigation of obstacles to the application of nursing research results in China, aiming to provide reference points for the evaluation and application of nursing research results in China.
基金Hydraulic Science and Technology Project of Water Resources Department of Jiangxi Province(202324YBKT14)Youth Science and Technology Innovation Fund of Jiangxi Hydrology Monitoring Center(SWJJKT202208).
文摘Based on the water quality monitoring data of 5 large reservoirs in Ji’an City,Jiangxi Province from 2015-2021,the temporal and spatial variation characteristics and trends of water quality of the reservoirs were analyzed by single-factor evaluation method and seasonal Kendall test to evaluate the trophic status of the reservoirs and explore the influencing factors of characteristic pollutants.The results showed that:①the water quality of the reservoirs was good and could meet the water needs of various functions;②the water quality of the reservoirs had generally changed from bad to good in recent years,indicating that the implementation of“river chief system”has achieved certain results;③Kendall test analysis showed that,except for individual projects which showed an upward trend in water quality,other projects showed no obvious change trend or downward trend,indicating that the water quality of the reservoirs is indeed improving;④the causes of water pollution in reservoir area were further analyzed by exploring the natural and human factors of the characteristic pollutant total phosphorus.It is recommended to strengthen supervision in the later stage to control point and non-point source pollution.
基金National Natural Science Foundation of China(51475291).
文摘Virtual reality(VR)has been widely used in various manufacturing industries,and VR-based virtual manufacturing has received significant attention in the current intelligent manufacturing era.Digital human models(DHMs)are essential for virtual manufacturing applications.Additionally,researching new applications of DHMs has developed into an important academic research field.This paper aims to identify the applications and research trends of DHMs in the manufacturing industry and to provide a reference for the continued development of virtual manufacturing and DHMs.We selected a total of 49 related articles from a large number of articles published between 2014 and 2019.The applications of DHMs in the manufacturing industry are analyzed from different perspectives and various relevant technical limitations are discussed.The results indicate that the applications of DHMs differ significantly between different types of fields.The automotive industry is the main application field for DHMs,and assembly/maintenance simulations and evaluations are the main application types.Additionally,there are still some limitations in the establishment of virtual environments,motion control,and DHM evaluation that should be addressed.Finally,research trends in the application of DHMs are illustrated and discussed,including the planning and assessment of human-robot collaboration systems,the combination of DHMs and augmented reality,and improved motion planning for DHMs.In summary,the application of DHMs can improve the realism and effectiveness of virtual manufacturing,and DHMs will be more widely and deeply studied and applied in various manufacturing industries in the near future.
文摘Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a comprehensive therapy for fulminant hepatitis. The following is a report of the results of using pHGF for the treatment of 1687 cases of fulminant hepatitis (with 1196 controls).
文摘Oversea hydrocarbon exploration always faces some problems,such as multiple basin types,different exploration prospects,various exploration degrees,diverse data quantities and geological recognitions.This paper focuses on overseas basins with different exploration degrees and offers a new evaluation system and research method for fast evaluation and risk analysis on hydrocarbon potential.Based on the theory of probability,this new evaluation system evaluates each parameter and core accumulation factor with comprehensive and quantitative assignment,to accelerate geological evaluation.In addition,this paper suggests that source rock evaluation should be the core criterion in screening evaluation of poorexplored basins,and also proposes that both the exploration potential and geological recognition should drive the evaluation for basins with high exploration degrees.This new system and method,which is an effective system for fast basin evaluation,is suggested to be used in oversea evaluation and decision-making objectively,scientifically and efficiently.
基金This paper is subsidized by National Social Science Fund ( No.99BJY0 55)
文摘The comprehensive evaluation of the schemes of coal mine design often involves some factors that are difficult to be expressed in quantity and these factors are often described qualitatively.Therefore, it is difficult for us to adopt uniformly concrete evaluation value to appraise each design plan. So the subjective view point of the design personnel plays an important role in choosing final plan. Sometime it will lead one sided decision, which will make the chosen scheme not optimized. Thus the quantitative model for evaluating design is set up by means of Fuzzy Mathematics and a concrete calculating example is given in this paper.\;The Fuzzy mathematical model proposed in this paper is good in adaptability and convenience. Both comments and degrees of importance in correspondence with the evaluated factors of each plan can be given qualitatively according to the people′s idiomatic expression by the model. After simple calculation, the quantitative result or comprehensive evaluation value that evaluates each design plan can be obtained,which provides a scientific basis for design personnel to choose the optimum scheme.
基金supported by the National Natural Science Foundation of China (Grant Nos. 52120105009 and 51906144)the Science and Technology Commission of Shanghai Municipality (Grant Nos. 20JC1414800 and 22ZR1432900)the Open Fund of Key Laboratory of Thermal Management and Energy Utilization of Aircraft of Ministry of Industry and Information Technology (Grant No. CEPE2020015)。
文摘The increasing demand for versatile and high-quality near-field radiative heat transfer(NFRHT) has created a critical need for a design approach that can handle numerous candidate structures. In this work, we employ and develop an adaptive hybrid Bayesian optimization(AHBO) algorithm to design the high-quality quasi-monochromatic NFRHT. The candidate materials include hexagonal boron nitride, silicon carbide, and doped silicon. The high-quality quasi-monochromatic NFRHT is optimized over 1.0 × 10^(8) candidate structures to maximize the evaluation factor. It is worth noting that only 2.6% of the candidate structures needed to be calculated to identify the optimal structure. The optimal structure of quasi-monochromatic NFRHT is an aperiodic multilayer metamaterial that differs from conventional periodic multilayer structures. Moreover, we investigate the robustness and mechanisms of the optimal quasi-monochromatic NFRHT with respect to the vacuum gap distance and the temperature difference between the emitter and receiver. In addition, the high-quality multi-peak NFRHT is designed using the AHBO algorithm by improving the definition of the evaluation factor. The results demonstrate that the AHBO algorithm is efficient in designing high-quality quasi-monochromatic and multi-peak NFRHT, and it can be further expanded to other structural designs in the field of energy conversion.
基金the Research Project of Education Department of Hunan Province(19C0026,ZJGB2020078)。
文摘The water quality of rivers flowing into lakes is a reflection of the regional environment and significantly contributes to the nutrient levels of the lake.Based on multi-year monitoring data of the estuarine water quality of the Zi River which flows into the Dongting Lake,single factor analysis was performed for the dissolved oxygen,nitrogen ammonia(NH3-N),chemical oxygen demand,total phosphorus,permanganate index,and biochemical oxygen demand.The analysis indicated that the estuarine water quality class was dependent on the NH3-N level.The NH3-N trend of the Zi River was then simulated using an improved grey model IGM(0,N)based on a grey correlation analysis.The IGM(0,N)model produced a smaller average relative error and a more accurate prediction compared with a multiple regression model,thus validating the use of the IGM(0,N)model as a suitable method to simulate the estuarine water quality with a complex multi-factor system.