It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval...It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.展开更多
The architecture and working principle of coordinated search and rescue system of unmanned/manned aircraft,which is composed of manned/unmanned aircraft and manned aircraft,were first introduced,and they can cooperate...The architecture and working principle of coordinated search and rescue system of unmanned/manned aircraft,which is composed of manned/unmanned aircraft and manned aircraft,were first introduced,and they can cooperate with each other to complete a search and rescue task.Secondly,a threat assessment method based on meteorological data was proposed,and potential meteorological threats,such as storms and rainfall,can be predicted by collecting and analyzing meteorological data.Finally,an experiment was carried out to evaluate the performance of the proposed method in different scenarios.The experimental results show that the coordinated search and rescue system of unmanned/manned aircraft can be used to effectively assess meteorological threats and provide accurate search and rescue guidance.展开更多
As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor ec...As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor economics alone can address the problems of our global commons. New measures of wealth, of value, of contributions and production are needed that acknowledge the 'natural capital' and 'ecosystem services' provided from healthy environments. A new interface is now being recognized termed 'eco-economics'. It is an ambitious and necessary attempt to understand the affairs of humanity and nature as a single, interdependent system. New tools are being invested to measure wealth. services and production fairly and equitably. In this report we use systems analysis approach to study the combined ecological-economic system of Tibet We use an alternative measure of value, based on real contributions to system performance, termed EMERGY, spelt with an 'M'. It is an accounting unit of total contributions, direct and indirect. used in generating a product or service. It is a concept derived from understanding whole systems, their interactions and interdependence, and the resources driving and maintaining them. This broader approach will help us to investigate Tibetan resources utilization and potentialities and exchange. Emergy analysis allows comparison and incroporation of environmental costs and benefits with variables of traditional economic costs and benefits to provide a more comprehensive perspective for public policy directives. Through this research, we think: 1) China has made a great effort in making Tibet develop from a closed regional system to a more and more opened regional system which is very important to the sustainable development of Tibet. 2) The increase of economic development and population growth has a close relationship with the total emergy storage and use in transportation. Education in modern science and technology increased the shared emergy of Tibetans to modern science and technology and stimulated the process of matching material and energy imports from outside with local resources. 3) There is great potential to develop hydropower and geothermal reserves that may stimulate not only economic development but also the better use of environment. 4) The better trained population can increase the empower of Tibet eco-economic system. Future development needs all kinds of talent exchanges with the outside system to develop education. 3) Compared with the Tibet economic system, Taiwan economic system is much more competitive. GNP and emergy use are very useful functions for comparing the competitive power of different ecological economic systems.展开更多
Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be di...Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be divided into socioeconomic and ecological sub-systems and their relationship can reveal the interaction state between the two sub-systems and help the local government to establish a coordinated development mode. An index system was constructed to assess the development of the two sub-systems before the evaluation of the degree of coupling and coordination. The principal component regression analysis was adopted to quantitatively assess the influences of natural, economic and social factors on the degree of coupling and coordination of the eco-economic system. Results showed that, from 1983 to 2014, the development trends of both sub-systems were increasing with the ecological sub-system having more fluctuations. The degree of coupling and coordination of the eco-economic system in the study area increased gradually from 1983 to 2014, but experienced five different development stages from the verge of disorder to favorable coordination. The development of the local social and economic conditions was the most important factor influencing the degree of coupling and coordination. The second most important factor was the financial support from the local government. In addition, the environment protection policies also played undeniable roles. Due to the diversity of the influence factors, the government should take comprehensive measures to promote the sustainable development of the eco-economic system.展开更多
Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound sys...Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound system of karst region in Guizhou Province were analyzed.The functional characteristics were as follows:low biological production of Guizhou Province;weak capacity of ecosystem;slow speed of storage and accumulation of material and serious environmental pollution;low production and efficiency of energy;serious wastes of energy.On the basis of functional characteristics of eco-economic compound System in Karst region.Some views in terms of maintenance and reconstruction of compound system,were put forward,including laying stress on improving ecological system;choosing and cultivating the advanced species that suit the Karst region;improving the amount and speed of material accumulation,at the same time,introducing into advanced production technologies and management experience;reducing the energy efficiency of each section in economic system and improving the transformation efficiency of energy.展开更多
To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province,this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010.The results showed that the va...To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province,this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010.The results showed that the value of regional agricultural emergy output increased by44.68%to(6.50 E)sej,but lower than the growth of non-agricultural industry output.Compared with 2001,the emergy output of planting industry was(4.10E)sej in 2010 which occupied 63.09%of the total agricultural emergy output and got an increase of 2.93 percentage points,while the emergy output of stock farming got a decrease of 2.87 percentage points.The growth of fishery emergy output was not in conformity with the characteristics of Dongting Rim in Hunan.From the contrast between emergy output and economic output,we could find that the economic return ratio of planting industry and fishery industry were lower than those of forestry industry and stock farming industry,which indicated that it is necessary to improve the economic benefits of planting industry and fishery industry which were the traditional industries with advantages of the Dongting Rim in Hunan.展开更多
Using emergy analysis method,I conduct quantitative analysis of social,economic and natural systems in Sichuan's Baisha River valley during the period 2002-2006,through the establishment of indicators.I compare th...Using emergy analysis method,I conduct quantitative analysis of social,economic and natural systems in Sichuan's Baisha River valley during the period 2002-2006,through the establishment of indicators.I compare the emergy of Baisha River valley,with that of Xinjiang's Manas River valley and Sichuan Province,and evaluate the sustainable development conditions in Baisha River valley,in order to provide corresponding reference for the development and utilization of Baisha River valley in the future.The results show that from the perspective of emergy input of economic system,Baisha River valley is a typical ecological and economic zone with rich resources to be developed;in terms of the development of natural conditions and utilization of ecological resources,the resource utilization intensity of Baisha River valley is weak and the environmental loading ratio there is low,thus the level of emergy yield needs to be improved;the system of Baisha River valley has enormous capacity for sustainable development and good potential for development.展开更多
基金supported by the National Natural Science Foundation of China (12072365)the Natural Science Foundation of Hunan Province of China (2020JJ4657)。
文摘It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.
基金the Study on the Impact of the Construction and Development of Southwest Plateau Airport on the Ecological Environment(CZKY2023032).
文摘The architecture and working principle of coordinated search and rescue system of unmanned/manned aircraft,which is composed of manned/unmanned aircraft and manned aircraft,were first introduced,and they can cooperate with each other to complete a search and rescue task.Secondly,a threat assessment method based on meteorological data was proposed,and potential meteorological threats,such as storms and rainfall,can be predicted by collecting and analyzing meteorological data.Finally,an experiment was carried out to evaluate the performance of the proposed method in different scenarios.The experimental results show that the coordinated search and rescue system of unmanned/manned aircraft can be used to effectively assess meteorological threats and provide accurate search and rescue guidance.
基金Under the auspices of the key project and special support programme of CAS !KZ931-Al- 204-05 CERN T/TA project! 98TOR17
文摘As economies and ecological support systems become more interdependent, new disciplines are needed to 'bridge the gap' of understanding between societies and nature. It is now clear that neither ecology nor economics alone can address the problems of our global commons. New measures of wealth, of value, of contributions and production are needed that acknowledge the 'natural capital' and 'ecosystem services' provided from healthy environments. A new interface is now being recognized termed 'eco-economics'. It is an ambitious and necessary attempt to understand the affairs of humanity and nature as a single, interdependent system. New tools are being invested to measure wealth. services and production fairly and equitably. In this report we use systems analysis approach to study the combined ecological-economic system of Tibet We use an alternative measure of value, based on real contributions to system performance, termed EMERGY, spelt with an 'M'. It is an accounting unit of total contributions, direct and indirect. used in generating a product or service. It is a concept derived from understanding whole systems, their interactions and interdependence, and the resources driving and maintaining them. This broader approach will help us to investigate Tibetan resources utilization and potentialities and exchange. Emergy analysis allows comparison and incroporation of environmental costs and benefits with variables of traditional economic costs and benefits to provide a more comprehensive perspective for public policy directives. Through this research, we think: 1) China has made a great effort in making Tibet develop from a closed regional system to a more and more opened regional system which is very important to the sustainable development of Tibet. 2) The increase of economic development and population growth has a close relationship with the total emergy storage and use in transportation. Education in modern science and technology increased the shared emergy of Tibetans to modern science and technology and stimulated the process of matching material and energy imports from outside with local resources. 3) There is great potential to develop hydropower and geothermal reserves that may stimulate not only economic development but also the better use of environment. 4) The better trained population can increase the empower of Tibet eco-economic system. Future development needs all kinds of talent exchanges with the outside system to develop education. 3) Compared with the Tibet economic system, Taiwan economic system is much more competitive. GNP and emergy use are very useful functions for comparing the competitive power of different ecological economic systems.
基金supported by the National Natural Science Foundation of China(41471436,41601587)the National Science and Technology Support Program of China(2015BAC06B01)+1 种基金the National Key Research and Development Program of China(2016YFC0500909)the National Natural Science Foundation of China(41601587)
文摘Based on the statistical data, we analyzed and evaluated the degree of coupling and coordination of the eco-economic system in Yanchi County for the period spanning from 1983 to 2014. The eco-economic system can be divided into socioeconomic and ecological sub-systems and their relationship can reveal the interaction state between the two sub-systems and help the local government to establish a coordinated development mode. An index system was constructed to assess the development of the two sub-systems before the evaluation of the degree of coupling and coordination. The principal component regression analysis was adopted to quantitatively assess the influences of natural, economic and social factors on the degree of coupling and coordination of the eco-economic system. Results showed that, from 1983 to 2014, the development trends of both sub-systems were increasing with the ecological sub-system having more fluctuations. The degree of coupling and coordination of the eco-economic system in the study area increased gradually from 1983 to 2014, but experienced five different development stages from the verge of disorder to favorable coordination. The development of the local social and economic conditions was the most important factor influencing the degree of coupling and coordination. The second most important factor was the financial support from the local government. In addition, the environment protection policies also played undeniable roles. Due to the diversity of the influence factors, the government should take comprehensive measures to promote the sustainable development of the eco-economic system.
文摘Based on the eco-economy theory,this paper analyzed the characteristics of the components of eco-economic compound system of karst region in Guizhou Province.The functional characteristics of eco-economic compound system of karst region in Guizhou Province were analyzed.The functional characteristics were as follows:low biological production of Guizhou Province;weak capacity of ecosystem;slow speed of storage and accumulation of material and serious environmental pollution;low production and efficiency of energy;serious wastes of energy.On the basis of functional characteristics of eco-economic compound System in Karst region.Some views in terms of maintenance and reconstruction of compound system,were put forward,including laying stress on improving ecological system;choosing and cultivating the advanced species that suit the Karst region;improving the amount and speed of material accumulation,at the same time,introducing into advanced production technologies and management experience;reducing the energy efficiency of each section in economic system and improving the transformation efficiency of energy.
基金Supported by National Social Science Fund Project(11BJY029)Hunan Provincial Conditions and Decision-making Advisory Research Project(2012BZZ16)Arts Tender Project of Central South University of Forestry and Technology(2011ZB003)
文摘To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province,this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010.The results showed that the value of regional agricultural emergy output increased by44.68%to(6.50 E)sej,but lower than the growth of non-agricultural industry output.Compared with 2001,the emergy output of planting industry was(4.10E)sej in 2010 which occupied 63.09%of the total agricultural emergy output and got an increase of 2.93 percentage points,while the emergy output of stock farming got a decrease of 2.87 percentage points.The growth of fishery emergy output was not in conformity with the characteristics of Dongting Rim in Hunan.From the contrast between emergy output and economic output,we could find that the economic return ratio of planting industry and fishery industry were lower than those of forestry industry and stock farming industry,which indicated that it is necessary to improve the economic benefits of planting industry and fishery industry which were the traditional industries with advantages of the Dongting Rim in Hunan.
文摘Using emergy analysis method,I conduct quantitative analysis of social,economic and natural systems in Sichuan's Baisha River valley during the period 2002-2006,through the establishment of indicators.I compare the emergy of Baisha River valley,with that of Xinjiang's Manas River valley and Sichuan Province,and evaluate the sustainable development conditions in Baisha River valley,in order to provide corresponding reference for the development and utilization of Baisha River valley in the future.The results show that from the perspective of emergy input of economic system,Baisha River valley is a typical ecological and economic zone with rich resources to be developed;in terms of the development of natural conditions and utilization of ecological resources,the resource utilization intensity of Baisha River valley is weak and the environmental loading ratio there is low,thus the level of emergy yield needs to be improved;the system of Baisha River valley has enormous capacity for sustainable development and good potential for development.
