Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimizatio...Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimization of equipment architecture design,the adequate resources allocation,and the joint combat performance.From the system view,this paper proposes a method of weapons equipment portfolios selection(WEPS)based on the contribution rate of weapon systems,providing a new idea for weapon equipment portfolio selection.Firstly,we analyze the WEPS problem and the concept of the contribution rate under the systems background.Secondly,we propose a combat network modeling method for weapon equipment systems based on the function chain.Thirdly,we propose a WEPS method based on the contribution rate,fully considering the correlation relationships between potential weapons and the old weapon systems by the combat network model,under the limitation of capability demands and budget resources,with the objective to maximally increasing the combat ability of weapon systems.Finally,we make a case study with a specific WEPS problem where the whole calculation processes and results are analyzed and exhibited to verify the feasibility and effectiveness of the proposed method model.展开更多
The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate ev...The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network.展开更多
To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation...To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation process of the equipment SoS contribution rate were redefined and standardized.To solve the existing problems in the application of the original contribution rate formula,a modified contribution rate calculation formula is proposed.Finally,the contribution rate evaluation index was divided into latent and explicit variables.The measurement and structural equations in the SEM were used to calculate and analyze the latent variables.The simulation results show that the number of defense lines of air defense weapon equipment has a greater impact on the linear configuration than the group configuration.When the number of K-type air defense weapons is sufficient,the two-layer linear configuration should be adopted with 20 air defense weapon systems.When the number of K-type air defense weapons is insufficient,the single-layer group configuration should be adopted with 12 air defense weapon systems.展开更多
A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis（ SPA） method is proposed to calculate the con...A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis（ SPA） method is proposed to calculate the contribution rate of PM2.5in Dongguan City. Due to geographic,meteorological factors and the low concentration of air pollutants in Qingxi area,the PM2.5in this place is mainly contributed by the regional transport of air pollutants from other inside areas of Dongguan,and less affected by the outside of Dongguan. So the concentration of PM2.5in Qingxi area can reflect the Dongguan＇s basic background concentration of PM2.5. On the basis of the basic background concentration,firstly the concentration of each pollutant components is divided into the internal part and the mixed part. Secondly using the source apportionment samples of five monitoring sites in Dongguan we can respectively construct a sample set A and an evaluation set B. Thirdly the SPA is operated onto the mixed part in terms of set B.At last the connection degree between the concentration of each pollutant components and external source and internal source will be calculated,that is the contribution rate. The research reveals that the contribution rate of internal source and external source of PM2.5in Dongguan City is 83%and 17% respectively,which roughly met expectations. This method is simple and effective and it can provide a reference for the government taking reduction measures to control PM2.5pollutants emission.展开更多
It is the rational and exact computation of the safety economy contribution rate that has the far-reaching realistic meaning to the improvement of society cognition to safety and the investment to the nation safety an...It is the rational and exact computation of the safety economy contribution rate that has the far-reaching realistic meaning to the improvement of society cognition to safety and the investment to the nation safety and the national macro-safety decision-makings. The accurate function between safety inputs and outputs was obtained through a founded econometric model. Then the forecasted safety economy contribution rate is 3.01% and the forecasted ratio between safety inputs and outputs is 1：1.81 in China in 2005. And the model accords with the practice of China and the results are sarisfying.展开更多
Agricultural informationization is the objective demand for transforming the traditional agriculture and promoting the development of agricultural modernization. Using the statistical data of the gross agricultural ou...Agricultural informationization is the objective demand for transforming the traditional agriculture and promoting the development of agricultural modernization. Using the statistical data of the gross agricultural output value of Hubei Province in 2005-2014,based on the C-D production function,it calculated the average contribution rate(2. 48%) of agricultural informationization to the growth of agricultural economy in Hubei Province,indicating that agricultural informationization can promote growth of agricultural economy. This is basically consistent with previous findings. In addition,investment in agricultural informationization and broadband access rate also influenced the growth of agricultural economy in Hubei Province. Therefore,government should further improve the infrastructure of agricultural informationization,strengthen training of farmers’ information skills,establish auxiliary mechanism for achievement feedback of information-based agricultural production,increase the contribution rate of informationization to agricultural operation and management,promote the contribution of informationization to the growth of agricultural economy,so as to increase agricultural income of farmers.展开更多
A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;how...A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking.Here,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.展开更多
Many studies have shown that energy consumption plays an important role in economic growth.The paper researches the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.The paper ...Many studies have shown that energy consumption plays an important role in economic growth.The paper researches the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.The paper divides the energy of Yangtze River Economic Zone into the coal,the oil,the natural gas and the electricity and explores the influences of coal consumption,gas consumption,natural gas consumption and electricity consumption on economic growth quantitatively using an extended production function model.The paper mainly uses two methods.The first method is the output elasticity analysis.The paper calculates the four energy consumption’s output elasticity to economic growth to compares the influences of energy consumption in terms of out output elasticity.The second method is the contribution rate analysis.The paper calculates the contribution rates of four energy consumption to economic growth to compare the influences of four energy consumption on economic growth in terms of contribution rate.The paper makes an empirical analysis on the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.Analysis results show that oil consumption has the greatest influence on economic growth in China’s Yangtze River Economic Zone,in terms of both output elasticity and contribution rate,followed by natural gas consumption,electricity consumption and coal consumption.展开更多
The contribution of the quark loop to the gluon damping rate at zero momentum is calculated using the effective perturbative expansion technique developed by Braaten and Pisarski. It is shown that in the temperature r...The contribution of the quark loop to the gluon damping rate at zero momentum is calculated using the effective perturbative expansion technique developed by Braaten and Pisarski. It is shown that in the temperature range accessible in the present heavy-ion experiments, the contribution of the quark loop can not be ignored. The numerical results show that the quark loop provides ~n apparent contribution to the gluon damping rate at temperatures of experimental interest.展开更多
This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regr...This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regression.Taking City Commercial Bank A as an instance,the model identifies 12.3%redundant positions and matches jobs with business scale.Additionally,the study proposes a“staffing effectiveness salary”system,providing a framework for optimizing commercial bank human capital in the digital age.展开更多
Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spat...Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spatiotemporal variations in ET_(0) over China from 1960 to 2019 were analyzed.We then quantified the contributions of five driving factors(air temperature,wind speed,relative humidity,sunshine hours,and CO_(2) concentration)to the ET_(0) trends via a detrending experiment.The results revealed that nationwide ET_(0) showed no significant(p>0.05)decreasing trend from 1960 to 2019,with a trend of−8.56×10^(−2)mm a^(−2).The average temperature and wind speed were identified as the dominant factors affecting ET_(0)trends at the national scale.The contributions of the driving factors to the ET_(0) trends were ranked in the following order:average temperature(21.3%)>wind speed(−15.63%)>sunshine hours(−11.99%)>CO_(2) concentration(6.36%)>relative humidity(3.58%).Spatially,the dominant factors influencing the ET_(0) trends varied widely.In the southeastern region,average temperature and sunshine hours dominated the trends of ET_(0),whereas wind speed and average temperature were the dominant factors in the northwestern region.The findings provide valuable insights into the dominant factors affecting ET_(0)trends in China and highlight the importance of considering different driving factors in calculating crop water requirements.展开更多
Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been mad...Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been made to explore their distribution patterns and ecological mechanisms that determine these patterns for more than 100 years, and quite a number of geographical and ecophysiological models have been developed to correlate treeline altitude with latitude or a latitude related temperature. However,on a global scale, all of these models have great difficulties to accurately predict treeline elevation due to the extreme diversity of treeline site conditions.One of the major reasons is that "mass elevation effect"(MEE) has not been quantified globally and related with global treeline elevations although it has been observed and its effect on treeline elevations in the Eurasian continent and Northern Hemisphere recognized. In this study, we collected and compiled a total of 594 treeline sites all over the world from literatures, and explored how MEE affects globaltreeline elevation by developing a ternary linear regression model with intra-mountain base elevation(IMBE, as a proxy of MEE), latitude and continentality as independent variables. The results indicated that IMBE, latitude and continentality together could explain 92% of global treeline elevation variability, and that IMBE contributes the most(52.2%), latitude the second(40%) and continentality the least(7.8%) to the altitudinal distribution of global treelines. In the Northern Hemisphere, the three factors' contributions amount to 50.4%, 45.9% and 3.7% respectively; in the south hemisphere, their contributions are 38.3%, 53%, and 8.7%, respectively. This indicates that MEE, virtually the heating effect of macro-landforms, is actually the most significant factor for the altitudinal distribution of treelines across the globe, and that latitude is relatively more significant for treeline elevation in the Southern Hemisphere probably due to fewer macro-landforms there.展开更多
We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner ...We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner than 75μm and was then heated to temperatures up to 900 ℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction（XRD） was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content（Wn）. The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700 ℃ and the dehydrated products are mainly β-C2 S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fl y ash, increasing the replacement level of fl y ash lowered them in AF. The strength contribution rates on pozzolanic effect of fl y ash in AF are always negative, showing a contrary tendency of that of cement-fl y ash system.展开更多
The Three-River Source Region(TRSR)in China holds a vital position and exhibits an irreplaceable strategic importance in ecological preservation at the national level.On the basis of an in-depth study of the vegetatio...The Three-River Source Region(TRSR)in China holds a vital position and exhibits an irreplaceable strategic importance in ecological preservation at the national level.On the basis of an in-depth study of the vegetation evolution in the TRSR from 2000 to 2022,we conducted a detailed analysis of the feedback mechanism of vegetation growth to climate change and human activity for different vegetation types.During the growing season,the spatiotemporal variations of normalized difference vegetation index(NDVI)for different vegetation types in the TRSR were analyzed using the Moderate Resolution Imaging Spectroradiometer(MODIS)-NDVI data and meteorological data from 2000 to 2022.In addition,the response characteristics of vegetation to temperature,precipitation,and human activity were assessed using trend analysis,partial correlation analysis,and residual analysis.Results indicated that,after in-depth research,from 2000 to 2022,the TRSR's average NDVI during the growing season was 0.3482.The preliminary ranking of the average NDVI for different vegetation types was as follows:shrubland(0.5762)>forest(0.5443)>meadow(0.4219)>highland vegetation(0.2223)>steppe(0.2159).The NDVI during the growing season exhibited a fluctuating growth trend,with an average growth rate of 0.0018/10a(P<0.01).Notably,forests displayed a significant development trend throughout the growing season,possessing the fastest rate of change in NDVI(0.0028/10a).Moreover,the upward trends in NDVI for forests and steppes exhibited extensive spatial distributions,with significant increases accounting for 95.23%and 93.80%,respectively.The sensitivity to precipitation was significantly enhanced in other vegetation types other than highland vegetation.By contrast,steppes,meadows,and highland vegetation demonstrated relatively high vulnerability to temperature fluctuations.A further detailed analysis revealed that climate change had a significant positive impact on the TRSR from 2000 to 2022,particularly in its northwestern areas,accounting for 85.05%of the total area.Meanwhile,human activity played a notable positive role in the southwestern and southeastern areas of the TRSR,covering 62.65%of the total area.Therefore,climate change had a significantly higher impact on NDVI during the growing season in the TRSR than human activity.展开更多
Based on the daily meteorological observation data of seven meteorological stations in southern Xizang from 1980 to 2021(April-October),the temporal and spatial variation characteristics and influencing factors of ari...Based on the daily meteorological observation data of seven meteorological stations in southern Xizang from 1980 to 2021(April-October),the temporal and spatial variation characteristics and influencing factors of aridity index(AI)in the growing season of major grain producing areas in Xizang were studied by using climate tendency rate,Mann-Kendal test,Morlet wavelet analysis,GIS hybrid interpolation method,Pearson correlation coefficient,contribution rate analysis and other methods.The results showed that the average AI in the main grain producing areas of Xizang was 1.7,which belonged to the semi-arid area,and the overall trend was decreasing(humidifying)(-0.036/10 a).The linear decreasing trend was different in different regions,and the area around Lhatse County was the most significant(-0.26/10 a).AI had no obvious abrupt change,and had long-and medium-term fluctuation characteristics of 24 years,6 years.The spatial distribution was uneven,and had the characteristics of‘shrinking arid area and expanding humid area.The contribution rates of the main climate influencing factors of AI varied in different regions.In general,the contribution rates after quantification was as follows:precipitation(34.9%)>relative humidity(28.4%)>sunshine(19.9%)>maximum temperature(12.4%).展开更多
The runoff of some rivers in the world especially in the arid and semi-arid areas has decreased remarkably with global or regional climate change and enhanced human activities. The runoff decrease in the arid and semi...The runoff of some rivers in the world especially in the arid and semi-arid areas has decreased remarkably with global or regional climate change and enhanced human activities. The runoff decrease in the arid and semi-arid areas of northern China has brought severe problems in livelihoods and ecology. To reveal the variation characteristics, trends of runoff and their influencing factors have been important scientific issues for drainage basin man- agement. The objective of this study was to analyze the variation trends of the runoff and quantitatively assess the contributions of precipitation and human activities to the runoff change in the Huangfuchuan River Basin based on the measured data in 1960-2008. Two inflection points （turning years） of 1979 and 1998 for the accumulative runoff change, and one inflection point of 1979 for the accumulative precipitation change were identified using the methods of accumulative anomaly analysis. The linear relationships between year and ac- cumulative runoff in 1960-1979, 1980-1997 and 1998-2008 and between year and accu- mulative precipitation in 1960-1979 and 1980-2008 were fitted. A new method of slope change ratio of accumulative quantity （SCRAQ） was put forward and used in this study to calculate the contributions of different factors to the runoff change. Taking 1960-1979 as the base period, the contribution rate of the precipitation and human activities to the decreased runoff was 36.43% and 63.57% in 1980-1997, and 16.81% and 83.19% in 1998-2008, re- spectively. The results will play an important role in the drainage basin management. More- over, the new method of SCRAQ can be applied in the quantitative evaluation of runoff change and impacts by different factors in the river basin of arid and semi-arid areas.展开更多
This study presents a soil and water integrated model(SWIM) and associated statistical analyses for the Huaihe River Basin(HRB) based on daily meteorological, river runoff, and water resource data encompassing the per...This study presents a soil and water integrated model(SWIM) and associated statistical analyses for the Huaihe River Basin(HRB) based on daily meteorological, river runoff, and water resource data encompassing the period between 1959 and 2015. The aim of this research is to quantitatively analyze the rate of contribution of upstream runoff to that of the midstream as well as the influence of climate change and human activities in this section of the river. Our goal is to explain why extreme precipitation is concentrated in the upper reaches of the HRB while floods tend to occur frequently in the middle reaches of this river basin. Results show that the rate of contribution of precipitation to runoff in the upper reaches of the HRB is significantly higher than temperature. Data show that the maximum contribution rate of upstream runoff to that of the midstream can be as high as 2.23%, while the contribution of temperature is just 0.38%. In contrast, the rate of contribution of human activities to runoff is 87.20% in the middle reaches of the HRB, while that due to climate change is 12.80%. Frequent flood disasters therefore occur in the middle reaches of the HRB because of the combined effects of extreme precipitation in the upper reaches and human activities in the middle sections.展开更多
The objective of this study is to quantify the values of greenhouse gases(GHGs) exchange in carbon equivalents of marshes and paddy fields in the Sanjiang Plain,Heilongjiang Province,China. We obtained the GHGs exchan...The objective of this study is to quantify the values of greenhouse gases(GHGs) exchange in carbon equivalents of marshes and paddy fields in the Sanjiang Plain,Heilongjiang Province,China. We obtained the GHGs exchange values based on comparable price by calculating the carbon sequestration values and the GHGs emission values of marshes and paddy fields respectively in four periods of 1982,1995,2000 and 2005. It is noted that the GHGs emission values are always negative. In this study,the marshes areas decreased from 1438977.0 to 775,132.2ha and the paddy fields areas increased from 417195.8 to 934205.0ha. The values of GHGs exchange of marshes varied from 135877.156×106 to 136882.534×106 yuan(RMB) and those of paddy fields varied from 1006.256×106 to 2767.645×106 yuan. The GHGs exchange values of marshes decreased from 1982 to 2005 on the whole,reversely,those of paddy fields increased,but those in 2005 were lower than those in 2000. In different periods,the GHGs exchange values were always higher in marshes than in paddy fields. The contribution rate of GHGs exchange values per unit area of marshes was also very high in different periods,and the maximum was up to 98.35% in 2005. As far as the whole wetland ecosystem(including marshes and paddy fields) ,assuming a linear change in GHGs exchange values,it represented a cumulative increase of 20926.757×106 yuan from 1982 to 2005. By adding GHGs exchange values increased during those four periods,we obtained a cumulative net increase values of GHGs exchange of wetland ecosystem of 18200.860×106 yuan. The results will be useful for understanding the indirect services provided by marshes and paddy fields.展开更多
Acetochlor is a widely used herbicide in agricultural production. Studies have shown that acetochlor has obvious environmental hormone effects, and long-term exposure may pose a threat to human health. To quantify the...Acetochlor is a widely used herbicide in agricultural production. Studies have shown that acetochlor has obvious environmental hormone effects, and long-term exposure may pose a threat to human health. To quantify the hazards of acetochlor in drinking water, a health risk assessment of acetochlor was conducted in major cities of China based on the data of acetochlor residue concentrations in drinking water. The approach of the Species Sensitivity Distributions(SSD) method is used to extrapolate from animal testing data to reflect worst case human toxicity. Results show that hazard quotients related to acetochlor residues in drinking water for different age groups range from 1.94 × 10-4 to 6.13 × 10-4, so, there are no indication of human risk. Compared to the total estimated hazard quotient from oral intake of acetochlor, the chronic exposure imputed to acetochlor residues in drinking water in China accounts for 0.4%. This paper recommends 0.02 mg/L to be the maximum acetochlor residue concentration level in drinking water and source water criteria.展开更多
基金supported by the National Natural Science Foundation of China(71690233)the Scientific Research Foundation of National University of Defense Technology(ZK19-16)the PLA military graduate student funding project.
文摘Equipment selection is an essential work in the research and development planning of equipment.The scientific and rational development of weapons equipment portfolios is of considerable significance to the optimization of equipment architecture design,the adequate resources allocation,and the joint combat performance.From the system view,this paper proposes a method of weapons equipment portfolios selection(WEPS)based on the contribution rate of weapon systems,providing a new idea for weapon equipment portfolio selection.Firstly,we analyze the WEPS problem and the concept of the contribution rate under the systems background.Secondly,we propose a combat network modeling method for weapon equipment systems based on the function chain.Thirdly,we propose a WEPS method based on the contribution rate,fully considering the correlation relationships between potential weapons and the old weapon systems by the combat network model,under the limitation of capability demands and budget resources,with the objective to maximally increasing the combat ability of weapon systems.Finally,we make a case study with a specific WEPS problem where the whole calculation processes and results are analyzed and exhibited to verify the feasibility and effectiveness of the proposed method model.
基金supported by the National Key Research and Development Project(2018YFB1700802)the National Natural Science Foundation of China(72071206)the Science and Technology Innovation Plan of Hunan Province(2020RC4046).
文摘The contribution rate of equipment system-of-systems architecture(ESoSA)is an important index to evaluate the equipment update,development,and architecture optimization.Since the traditional ESoSA contribution rate evaluation method does not make full use of the fuzzy information and uncertain information in the equipment system-of-systems(ESoS),and the Bayesian network is an effective tool to solve the uncertain information,a new ESoSA contribution rate evaluation method based on the fuzzy Bayesian network(FBN)is proposed.Firstly,based on the operation loop theory,an ESoSA is constructed considering three aspects:reconnaissance equipment,decision equipment,and strike equipment.Next,the fuzzy set theory is introduced to construct the FBN of ESoSA to deal with fuzzy information and uncertain information.Furthermore,the fuzzy importance index of the root node of the FBN is used to calculate the contribution rate of the ESoSA,and the ESoSA contribution rate evaluation model based on the root node fuzzy importance is established.Finally,the feasibility and rationality of this method are validated via an empirical case study of aviation ESoSA.Compared with traditional methods,the evaluation method based on FBN takes various failure states of equipment into consideration,is free of acquiring accurate probability of traditional equipment failure,and models the uncertainty of the relationship between equipment.The proposed method not only supplements and improves the ESoSA contribution rate assessment method,but also broadens the application scope of the Bayesian network.
基金The National Social Science Foundation Military Science Project(No.16GJ003-068).
文摘To scientifically evaluate the equipment system of systems(SoS)contribution rate,a contribution rate calculation method based on a structural equation model(SEM)is proposed in this paper.The connotation and evaluation process of the equipment SoS contribution rate were redefined and standardized.To solve the existing problems in the application of the original contribution rate formula,a modified contribution rate calculation formula is proposed.Finally,the contribution rate evaluation index was divided into latent and explicit variables.The measurement and structural equations in the SEM were used to calculate and analyze the latent variables.The simulation results show that the number of defense lines of air defense weapon equipment has a greater impact on the linear configuration than the group configuration.When the number of K-type air defense weapons is sufficient,the two-layer linear configuration should be adopted with 20 air defense weapon systems.When the number of K-type air defense weapons is insufficient,the single-layer group configuration should be adopted with 12 air defense weapon systems.
基金Supported by National Natural Science Foundation of China(71171089)Research for PM_(2.5) Contamination Characteristics and Prevention and Control Countermeasures in Dongguan City(Dongcaidan[2013]222)
文摘A problem of the air pollution control in China is getting to know a regional contribution rate of internal and external source of PM2.5. In this paper,Set Pair Analysis（ SPA） method is proposed to calculate the contribution rate of PM2.5in Dongguan City. Due to geographic,meteorological factors and the low concentration of air pollutants in Qingxi area,the PM2.5in this place is mainly contributed by the regional transport of air pollutants from other inside areas of Dongguan,and less affected by the outside of Dongguan. So the concentration of PM2.5in Qingxi area can reflect the Dongguan＇s basic background concentration of PM2.5. On the basis of the basic background concentration,firstly the concentration of each pollutant components is divided into the internal part and the mixed part. Secondly using the source apportionment samples of five monitoring sites in Dongguan we can respectively construct a sample set A and an evaluation set B. Thirdly the SPA is operated onto the mixed part in terms of set B.At last the connection degree between the concentration of each pollutant components and external source and internal source will be calculated,that is the contribution rate. The research reveals that the contribution rate of internal source and external source of PM2.5in Dongguan City is 83%and 17% respectively,which roughly met expectations. This method is simple and effective and it can provide a reference for the government taking reduction measures to control PM2.5pollutants emission.
基金Supported by the National Natural Science Foundation of China(50274060) State Administration of Work Safety(03-103)
文摘It is the rational and exact computation of the safety economy contribution rate that has the far-reaching realistic meaning to the improvement of society cognition to safety and the investment to the nation safety and the national macro-safety decision-makings. The accurate function between safety inputs and outputs was obtained through a founded econometric model. Then the forecasted safety economy contribution rate is 3.01% and the forecasted ratio between safety inputs and outputs is 1：1.81 in China in 2005. And the model accords with the practice of China and the results are sarisfying.
基金Supported by Soft Science Project of Wuhan City in Hubei Province(201604-0306010178)
文摘Agricultural informationization is the objective demand for transforming the traditional agriculture and promoting the development of agricultural modernization. Using the statistical data of the gross agricultural output value of Hubei Province in 2005-2014,based on the C-D production function,it calculated the average contribution rate(2. 48%) of agricultural informationization to the growth of agricultural economy in Hubei Province,indicating that agricultural informationization can promote growth of agricultural economy. This is basically consistent with previous findings. In addition,investment in agricultural informationization and broadband access rate also influenced the growth of agricultural economy in Hubei Province. Therefore,government should further improve the infrastructure of agricultural informationization,strengthen training of farmers’ information skills,establish auxiliary mechanism for achievement feedback of information-based agricultural production,increase the contribution rate of informationization to agricultural operation and management,promote the contribution of informationization to the growth of agricultural economy,so as to increase agricultural income of farmers.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(Grant Nos.2019QZKK0606&2019QZKK0906)。
文摘A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking.Here,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.
基金Supported by the National Natural Science Foundation of China(11401418)。
文摘Many studies have shown that energy consumption plays an important role in economic growth.The paper researches the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.The paper divides the energy of Yangtze River Economic Zone into the coal,the oil,the natural gas and the electricity and explores the influences of coal consumption,gas consumption,natural gas consumption and electricity consumption on economic growth quantitatively using an extended production function model.The paper mainly uses two methods.The first method is the output elasticity analysis.The paper calculates the four energy consumption’s output elasticity to economic growth to compares the influences of energy consumption in terms of out output elasticity.The second method is the contribution rate analysis.The paper calculates the contribution rates of four energy consumption to economic growth to compare the influences of four energy consumption on economic growth in terms of contribution rate.The paper makes an empirical analysis on the influence of energy consumption on economic growth in China’s Yangtze River Economic Zone.Analysis results show that oil consumption has the greatest influence on economic growth in China’s Yangtze River Economic Zone,in terms of both output elasticity and contribution rate,followed by natural gas consumption,electricity consumption and coal consumption.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11465021 and 11065010
文摘The contribution of the quark loop to the gluon damping rate at zero momentum is calculated using the effective perturbative expansion technique developed by Braaten and Pisarski. It is shown that in the temperature range accessible in the present heavy-ion experiments, the contribution of the quark loop can not be ignored. The numerical results show that the quark loop provides ~n apparent contribution to the gluon damping rate at temperatures of experimental interest.
文摘This research centers on commercial banks'human resource allocation.It constructs a staffing model grounded in human capital value creation theory and analyzes relevant factors through longitudinal panel data regression.Taking City Commercial Bank A as an instance,the model identifies 12.3%redundant positions and matches jobs with business scale.Additionally,the study proposes a“staffing effectiveness salary”system,providing a framework for optimizing commercial bank human capital in the digital age.
基金National Natural Science Foundation of China,No.42277191,No.42377072,No.42107087。
文摘Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spatiotemporal variations in ET_(0) over China from 1960 to 2019 were analyzed.We then quantified the contributions of five driving factors(air temperature,wind speed,relative humidity,sunshine hours,and CO_(2) concentration)to the ET_(0) trends via a detrending experiment.The results revealed that nationwide ET_(0) showed no significant(p>0.05)decreasing trend from 1960 to 2019,with a trend of−8.56×10^(−2)mm a^(−2).The average temperature and wind speed were identified as the dominant factors affecting ET_(0)trends at the national scale.The contributions of the driving factors to the ET_(0) trends were ranked in the following order:average temperature(21.3%)>wind speed(−15.63%)>sunshine hours(−11.99%)>CO_(2) concentration(6.36%)>relative humidity(3.58%).Spatially,the dominant factors influencing the ET_(0) trends varied widely.In the southeastern region,average temperature and sunshine hours dominated the trends of ET_(0),whereas wind speed and average temperature were the dominant factors in the northwestern region.The findings provide valuable insights into the dominant factors affecting ET_(0)trends in China and highlight the importance of considering different driving factors in calculating crop water requirements.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41030528 and No. 40971064)
文摘Alpine treeline, as a prominent ecological boundary between forested mountain slopes and alpine meadow/shrub, is highly complex in altitudinal distribution and sensitive to warming climate. Great efforts have been made to explore their distribution patterns and ecological mechanisms that determine these patterns for more than 100 years, and quite a number of geographical and ecophysiological models have been developed to correlate treeline altitude with latitude or a latitude related temperature. However,on a global scale, all of these models have great difficulties to accurately predict treeline elevation due to the extreme diversity of treeline site conditions.One of the major reasons is that "mass elevation effect"(MEE) has not been quantified globally and related with global treeline elevations although it has been observed and its effect on treeline elevations in the Eurasian continent and Northern Hemisphere recognized. In this study, we collected and compiled a total of 594 treeline sites all over the world from literatures, and explored how MEE affects globaltreeline elevation by developing a ternary linear regression model with intra-mountain base elevation(IMBE, as a proxy of MEE), latitude and continentality as independent variables. The results indicated that IMBE, latitude and continentality together could explain 92% of global treeline elevation variability, and that IMBE contributes the most(52.2%), latitude the second(40%) and continentality the least(7.8%) to the altitudinal distribution of global treelines. In the Northern Hemisphere, the three factors' contributions amount to 50.4%, 45.9% and 3.7% respectively; in the south hemisphere, their contributions are 38.3%, 53%, and 8.7%, respectively. This indicates that MEE, virtually the heating effect of macro-landforms, is actually the most significant factor for the altitudinal distribution of treelines across the globe, and that latitude is relatively more significant for treeline elevation in the Southern Hemisphere probably due to fewer macro-landforms there.
基金Funded by the"863"National High-tech Research and Development Program of China(No.2012AA06A112)
文摘We experimentally studied the interaction between pozzolanic material（fly ash） and dehydrated autoclaved aerated concrete（DAAC）. The DAAC powder was obtained by grinding aerated concrete waste to particles fi ner than 75μm and was then heated to temperatures up to 900 ℃. New cementitious material was prepared by proportioning fly ash and DAAC, named as AF. X-ray diffraction（XRD） was employed to identify the crystalline phases of DAAC before and after rehydration. The hydration process of AF was analyzed by the heat of hydration and non-evaporable water content（Wn）. The experimental results show that the highest reactivity of DAAC can be obtained by calcining the powder at 700 ℃ and the dehydrated products are mainly β-C2 S and CaO. The cumulative heat of hydration and Wn was found to be strongly dependent on the replacement level of fl y ash, increasing the replacement level of fl y ash lowered them in AF. The strength contribution rates on pozzolanic effect of fl y ash in AF are always negative, showing a contrary tendency of that of cement-fl y ash system.
基金supported by the National Natural Science Foundation of China (42377472, 42174055)the Jiangxi Provincial Social Science "Fourteenth Five-Year Plan" (2024) Fund Project (24GL45)+1 种基金the Research Center of Resource and Environment Economics (20RGL01)the Provincial Finance Project of Jiangxi Academy of Sciences-Young Talent Cultivation Program (2023YSBG50010)
文摘The Three-River Source Region(TRSR)in China holds a vital position and exhibits an irreplaceable strategic importance in ecological preservation at the national level.On the basis of an in-depth study of the vegetation evolution in the TRSR from 2000 to 2022,we conducted a detailed analysis of the feedback mechanism of vegetation growth to climate change and human activity for different vegetation types.During the growing season,the spatiotemporal variations of normalized difference vegetation index(NDVI)for different vegetation types in the TRSR were analyzed using the Moderate Resolution Imaging Spectroradiometer(MODIS)-NDVI data and meteorological data from 2000 to 2022.In addition,the response characteristics of vegetation to temperature,precipitation,and human activity were assessed using trend analysis,partial correlation analysis,and residual analysis.Results indicated that,after in-depth research,from 2000 to 2022,the TRSR's average NDVI during the growing season was 0.3482.The preliminary ranking of the average NDVI for different vegetation types was as follows:shrubland(0.5762)>forest(0.5443)>meadow(0.4219)>highland vegetation(0.2223)>steppe(0.2159).The NDVI during the growing season exhibited a fluctuating growth trend,with an average growth rate of 0.0018/10a(P<0.01).Notably,forests displayed a significant development trend throughout the growing season,possessing the fastest rate of change in NDVI(0.0028/10a).Moreover,the upward trends in NDVI for forests and steppes exhibited extensive spatial distributions,with significant increases accounting for 95.23%and 93.80%,respectively.The sensitivity to precipitation was significantly enhanced in other vegetation types other than highland vegetation.By contrast,steppes,meadows,and highland vegetation demonstrated relatively high vulnerability to temperature fluctuations.A further detailed analysis revealed that climate change had a significant positive impact on the TRSR from 2000 to 2022,particularly in its northwestern areas,accounting for 85.05%of the total area.Meanwhile,human activity played a notable positive role in the southwestern and southeastern areas of the TRSR,covering 62.65%of the total area.Therefore,climate change had a significantly higher impact on NDVI during the growing season in the TRSR than human activity.
基金Supported by Natural Science Foundation of Xizang Autonomous Region(XZ202001ZR0082G)National Key Research and Development Program of China(2020YFA0608203)Key Research and Development of Science and Technology Program of Xizang Autonomous Region(CGZH2024000002)。
文摘Based on the daily meteorological observation data of seven meteorological stations in southern Xizang from 1980 to 2021(April-October),the temporal and spatial variation characteristics and influencing factors of aridity index(AI)in the growing season of major grain producing areas in Xizang were studied by using climate tendency rate,Mann-Kendal test,Morlet wavelet analysis,GIS hybrid interpolation method,Pearson correlation coefficient,contribution rate analysis and other methods.The results showed that the average AI in the main grain producing areas of Xizang was 1.7,which belonged to the semi-arid area,and the overall trend was decreasing(humidifying)(-0.036/10 a).The linear decreasing trend was different in different regions,and the area around Lhatse County was the most significant(-0.26/10 a).AI had no obvious abrupt change,and had long-and medium-term fluctuation characteristics of 24 years,6 years.The spatial distribution was uneven,and had the characteristics of‘shrinking arid area and expanding humid area.The contribution rates of the main climate influencing factors of AI varied in different regions.In general,the contribution rates after quantification was as follows:precipitation(34.9%)>relative humidity(28.4%)>sunshine(19.9%)>maximum temperature(12.4%).
基金National Basic Research Program of China,No.2010CB428404
文摘The runoff of some rivers in the world especially in the arid and semi-arid areas has decreased remarkably with global or regional climate change and enhanced human activities. The runoff decrease in the arid and semi-arid areas of northern China has brought severe problems in livelihoods and ecology. To reveal the variation characteristics, trends of runoff and their influencing factors have been important scientific issues for drainage basin man- agement. The objective of this study was to analyze the variation trends of the runoff and quantitatively assess the contributions of precipitation and human activities to the runoff change in the Huangfuchuan River Basin based on the measured data in 1960-2008. Two inflection points （turning years） of 1979 and 1998 for the accumulative runoff change, and one inflection point of 1979 for the accumulative precipitation change were identified using the methods of accumulative anomaly analysis. The linear relationships between year and ac- cumulative runoff in 1960-1979, 1980-1997 and 1998-2008 and between year and accu- mulative precipitation in 1960-1979 and 1980-2008 were fitted. A new method of slope change ratio of accumulative quantity （SCRAQ） was put forward and used in this study to calculate the contributions of different factors to the runoff change. Taking 1960-1979 as the base period, the contribution rate of the precipitation and human activities to the decreased runoff was 36.43% and 63.57% in 1980-1997, and 16.81% and 83.19% in 1998-2008, re- spectively. The results will play an important role in the drainage basin management. More- over, the new method of SCRAQ can be applied in the quantitative evaluation of runoff change and impacts by different factors in the river basin of arid and semi-arid areas.
基金National Natural Science Foundation of China,No.41571018
文摘This study presents a soil and water integrated model(SWIM) and associated statistical analyses for the Huaihe River Basin(HRB) based on daily meteorological, river runoff, and water resource data encompassing the period between 1959 and 2015. The aim of this research is to quantitatively analyze the rate of contribution of upstream runoff to that of the midstream as well as the influence of climate change and human activities in this section of the river. Our goal is to explain why extreme precipitation is concentrated in the upper reaches of the HRB while floods tend to occur frequently in the middle reaches of this river basin. Results show that the rate of contribution of precipitation to runoff in the upper reaches of the HRB is significantly higher than temperature. Data show that the maximum contribution rate of upstream runoff to that of the midstream can be as high as 2.23%, while the contribution of temperature is just 0.38%. In contrast, the rate of contribution of human activities to runoff is 87.20% in the middle reaches of the HRB, while that due to climate change is 12.80%. Frequent flood disasters therefore occur in the middle reaches of the HRB because of the combined effects of extreme precipitation in the upper reaches and human activities in the middle sections.
基金Under the auspices of National Natural Science Foundation of China (No. 40830535)Frontier of Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (No. KZCX3-SW-NA3-01)
文摘The objective of this study is to quantify the values of greenhouse gases(GHGs) exchange in carbon equivalents of marshes and paddy fields in the Sanjiang Plain,Heilongjiang Province,China. We obtained the GHGs exchange values based on comparable price by calculating the carbon sequestration values and the GHGs emission values of marshes and paddy fields respectively in four periods of 1982,1995,2000 and 2005. It is noted that the GHGs emission values are always negative. In this study,the marshes areas decreased from 1438977.0 to 775,132.2ha and the paddy fields areas increased from 417195.8 to 934205.0ha. The values of GHGs exchange of marshes varied from 135877.156×106 to 136882.534×106 yuan(RMB) and those of paddy fields varied from 1006.256×106 to 2767.645×106 yuan. The GHGs exchange values of marshes decreased from 1982 to 2005 on the whole,reversely,those of paddy fields increased,but those in 2005 were lower than those in 2000. In different periods,the GHGs exchange values were always higher in marshes than in paddy fields. The contribution rate of GHGs exchange values per unit area of marshes was also very high in different periods,and the maximum was up to 98.35% in 2005. As far as the whole wetland ecosystem(including marshes and paddy fields) ,assuming a linear change in GHGs exchange values,it represented a cumulative increase of 20926.757×106 yuan from 1982 to 2005. By adding GHGs exchange values increased during those four periods,we obtained a cumulative net increase values of GHGs exchange of wetland ecosystem of 18200.860×106 yuan. The results will be useful for understanding the indirect services provided by marshes and paddy fields.
基金supported by the Foundation of Major Science and Technology Program for Water Pollution Control and Treatment (No. 2018ZX07502001)the National Natural Science Foundation of China (Nos. 21976205, 21477158 and 11771241)。
文摘Acetochlor is a widely used herbicide in agricultural production. Studies have shown that acetochlor has obvious environmental hormone effects, and long-term exposure may pose a threat to human health. To quantify the hazards of acetochlor in drinking water, a health risk assessment of acetochlor was conducted in major cities of China based on the data of acetochlor residue concentrations in drinking water. The approach of the Species Sensitivity Distributions(SSD) method is used to extrapolate from animal testing data to reflect worst case human toxicity. Results show that hazard quotients related to acetochlor residues in drinking water for different age groups range from 1.94 × 10-4 to 6.13 × 10-4, so, there are no indication of human risk. Compared to the total estimated hazard quotient from oral intake of acetochlor, the chronic exposure imputed to acetochlor residues in drinking water in China accounts for 0.4%. This paper recommends 0.02 mg/L to be the maximum acetochlor residue concentration level in drinking water and source water criteria.
