Radio frequency(RF)-based drone identification technologies have the advantages of long effective distances and low environmental dependence,which has become indispensable for drone surveillance systems.However,since ...Radio frequency(RF)-based drone identification technologies have the advantages of long effective distances and low environmental dependence,which has become indispensable for drone surveillance systems.However,since drones operate in unlicensed frequency bands,a large number of co-frequency devices exist in these bands,which brings a great challenge to traditional signal identification methods.Deep learning techniques provide a new approach to complete endto-end signal identification by directly learning the distribution of RF data.In such scenarios,due to the complexity and high dynamics of the electromagnetic environments,a massive amount of data that can reflect the various propagation conditions of drone signals is necessary for a robust neural network(NN)for identifying drones.In reality,signal acquisition and labeling that meet the above requirements are too costly to implement.Therefore,we propose a virtual electromagnetic environment modeling based data augmentation(DA)method to improve the diversity of drone signal data.The DA method focuses on simulating the spectrograms of drone signals transmitted in real-world environments and randomly generates extra training data in each training epoch.Furthermore,considering the limited processing capability of RF receivers,we modify the original YOLOv5s model to a more lightweight version.Without losing the identification performance,more hardware-friendly designs are applied and the number of parameters decreases about 10-fold.For performance evaluation,we utilized a universal software radio peripheral(USRP)X310 platform to collect RF signals of four drones in an anechoic chamber and a practical wireless scenario.Experiment results reveal that the NN trained with augmented data performs as well as that trained with practical data in the complex electromagnetic environment.展开更多
The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo ext...The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo extensive in-house tests and prolonged field tests for certification and approval before operational deployment,leading to high costs,delays,and operational disruptions.This paper introduces a GNSS-based train control localization framework which eliminates the need for on-site testing by leveraging train movement dynamics and 3D environment modeling to create a zero on-site testing platform.The proposed framework simulates train movement and the surrounding 3D environment using collected railway line location data and environmental attributes to generate realistic multipath signals and obscuration effects.This approach enables comprehensive laboratory-based case studies for train localization,reducing the huge amount test of needed for physical field trials.The framework is established in house,using the data collected at the Test Base of China Academy of Railway Sciences(Circular Railway).Results from the open area and cutting environment tests demonstrate high localization accuracy repeatability within the simulated environment,validating the feasibility and effectiveness of zero on-site testing for GNSS-based train control systems.This research highlights the potential of GNSS simulation platforms in enhancing cost efficiency,operational safety,and accuracy for future digital railways.展开更多
With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects （alternatives） for obtaining the best environmental qua...With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects （alternatives） for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports＇ information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals （WSI）, the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them.展开更多
Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment mon...Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).展开更多
More effective environmental pollution control and management are needed due to the increasing environ-mental impacts from a range of human activities and the growing public demands for a better living environment. Ur...More effective environmental pollution control and management are needed due to the increasing environ-mental impacts from a range of human activities and the growing public demands for a better living environment. Urban air pollution is a serious environmental issue that poses adverse impacts on the health of people and the environment in most metropolitan areas. In this paper,we propose a geoinformatics augmented framework of environmental modelling and information sharing for supporting effective urban air pollution control and management. This framework is out-lined in terms of its key components and processes including: 1) an integrated,adaptive network of sensors for envi-ronmental monitoring; 2) a set of distributed,interoperable databases for data management; 3) a set of intelligent,robust algorithms and models for environmental modelling; 4) a set of flexible,efficient user interfaces for data access and in-formation sharing; and 5) a reliable,high capacity,high performance computing and communication infrastructure for integrating and supporting other framework components and processes.展开更多
Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a ...Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a mining city in Northeast China,were studied. The results showed that,due to scale effect,the drainage of three important industrial wastewater pollutants(COD,NH3-N and petroleum) increased 8505t,671t and 384t,respectively,and due to structure effect,those pollutants drainage increased 3996t,174t and 120t from 2001 to 2006. While due to technological effect,the drainage of COD,NH3-N and petroleum reduced 4452t,458t and 331t,and due to cross effect,those pollutants drainage reduced 7270t,575t and 476t simultaneously. Meantime,the relationships between household consumption structure and domestic sewage discharge were analyzed,and domestic sewage discharges in different income levels were also compared. The results showed that,the domestic sewage discharges would increase 376t with 1000 yuan(RMB) increased in the traffic and communication consumption,and they would be 344t,219t,428t,1873t,respectively,in housing consumption,food consumption,medical consumption,miscellaneous commodity consumption. The proportion of domestic sewage discharge increased for high income residents significantly,but reduced for lower income residents. The industrial wastewater pollutants drainage tends to be reduced by technical progress,while domestic sewage discharge will be a more important factor for urban water environment quality.展开更多
The structure and characteristics of a large multi-parameter environmental simulation cabin are introduced.Due to the diffculties of control methods and the easily damaged characteristics,control systems for the large...The structure and characteristics of a large multi-parameter environmental simulation cabin are introduced.Due to the diffculties of control methods and the easily damaged characteristics,control systems for the large multi-parameter environmental simulation cabin are diffcult to be controlled quickly and accurately with a classical PID algorithm.Considering the dynamic state characteristics of the environmental simulation test chamber,a lumped parameter model of the control system is established to accurately control the multiple parameters of the environmental chamber and a fuzzy control algorithm combined with expert-PID decision is introduced into the temperature,pressure,and rotation speed control systems.Both simulations and experimental results have shown that compared with classical PID control,this fuzzy-expert control method can decrease overshoot as well as enhance the capacity of anti-dynamic disturbance with robustness.It can also resolve the contradiction between rapidity and small overshoot,and is suitable for application in a large multi-parameter environmental simulation cabin control system.展开更多
The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role...The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production（EDSP） model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors（favorable spawning habitat areas with sea surface temperature of 16–18°C） were assumed to be closely associated with carrying capacity（K） in the EDSP model. Deviance Information Criterion（DIC） values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield（MSY） from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F（0.1） and F（MSY）. Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management.展开更多
To investigate tumor-induced angiogenesis under the influence of the mechanical environments inside and outside the tumor, mathematical model of tumor angiogenesis was developed. In the model, extra-cellular matrix （...To investigate tumor-induced angiogenesis under the influence of the mechanical environments inside and outside the tumor, mathematical model of tumor angiogenesis was developed. In the model, extra-cellular matrix （ECM） was treated as a thin plane. The displacement of ECM is obtained from the force balance equation consisted of the ECs traction, the ECM visco-elastic forces and the exter- nal forces. Simulation results show that a layered capillary network is obtained with a well vascularized region at the periphery of the tumor. The present model can be used as a valid theoretical method in the basic researches in tumorinduced angiogenesis.展开更多
A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic co...A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic control of the temperature–pressure two-parameter and overcome the control difficulties inherent to a large inertia lag link with a complex control system which is composed of turbine refrigeration device, vacuum device and liquid nitrogen cooling device. The system includes multi-parameter decoupling of the cabin itself to avoid equipment damage of air refrigeration turbine caused by improper operation. Based on analysis of the dynamic characteristics and modeling for variations in temperature, pressure and rotation speed, an intelligent controller was implemented that includes decoupling and fuzzy arithmetic combined with an expert PID controller to control test parameters by decoupling and slope tracking control strategy. The control system employed centralized management in an open industrial ethernet architecture with an industrial computer at the core. The simulation and field debugging and running results show that this method can solve the problems of a poor anti-interference performance typical for a conventional PID and overshooting that can readily damage equipment. The steady-state characteristics meet the system requirements.展开更多
JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Tra...JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.展开更多
This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform...This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform. Based on the traditional environmental “Kuznets” model, the factor of environmental tax is added to verify the effect of environmental governance of environmental tax. The results show that: 1) the improvement of sulfur dioxide emission charge standard can effectively inhibit industrial sulfur dioxide emission, which verifies the existence of environmental effect of pollution levy policies</span><span style="font-family:"">.</span><span style="font-family:""> 2) The improvement of sewage charge standard has better inhibitory effect on sulfur dioxide emission per unit GDP than on sulfur dioxide emission</span><span style="font-family:"">.</span><span style="font-family:""> 3) There is regional heterogeneity in the “emission reduction” effect of sulfur dioxide emission charges in the eastern, central and western regions of China. Pollutants should be taxed differently according to regional differences</span><span style="font-family:"">.</span><span style="font-family:""> 4) Economic growth and sulfur dioxide emission show an inverted “U” shape, China is still in the stage before the inflection point of EKC. Economic growth still takes environmental damage as the cost, and the “emission reduction” effect of technological progress is not ideal, which reveals the urgency of increasing technological development in the field of green environmental protection under the current situation.展开更多
The purpose of this paper is to analyse mathematical models used in environmental modelling. Following a brief survey of the development in modelling scale- and time-dependent dispersion processes in the environment, ...The purpose of this paper is to analyse mathematical models used in environmental modelling. Following a brief survey of the development in modelling scale- and time-dependent dispersion processes in the environment, this paper compares three similarity solutions, one of which is a solution of the generalized Feller equation （GF） with fractal parameters, and the other two for the newly-developed generalized Fokker-Planck equation （GFP）. The three solutions are derived with parameters having physical significance. Data from field experiments are used to verify the solutions. The analyses indicate that the solutions of both GF and GFP represent the physically meaningful natural processes, and simulate the realistic shapes of tracer breakthrough curves.展开更多
The motive of these investigations is to provide the importance and significance of the fractional order(FO)derivatives in the nonlinear environmental and economic(NEE)model,i.e.,FO-NEE model.The dynamics of the NEE m...The motive of these investigations is to provide the importance and significance of the fractional order(FO)derivatives in the nonlinear environmental and economic(NEE)model,i.e.,FO-NEE model.The dynamics of the NEE model achieves more precise by using the form of the FO derivative.The investigations through the non-integer and nonlinear mathematical form to define the FO-NEE model are also provided in this study.The composition of the FO-NEEmodel is classified into three classes,execution cost of control,system competence of industrial elements and a new diagnostics technical exclusion cost.The mathematical FO-NEE system is numerically studied by using the artificial neural networks(ANNs)along with the Levenberg-Marquardt backpropagation method(ANNs-LMBM).Three different cases using the FO derivative have been examined to present the numerical performances of the FO-NEE model.The data is selected to solve the mathematical FO-NEE system is executed as 70%for training and 15%for both testing and certification.The exactness of the proposed ANNs-LMBM is observed through the comparison of the obtained and the Adams-Bashforth-Moulton database results.To ratify the aptitude,validity,constancy,exactness,and competence of the ANNs-LMBM,the numerical replications using the state transitions,regression,correlation,error histograms and mean square error are also described.展开更多
A brief review of the basic terminology on simulation, simulation life-cycle activities such as model-based activities, behavior-oriented activities, and quality assurance activities is given. Then, the challenges and...A brief review of the basic terminology on simulation, simulation life-cycle activities such as model-based activities, behavior-oriented activities, and quality assurance activities is given. Then, the challenges and opportunities for the advancement of the state-of-the-art in simulation environments are discussed under the following headings: modelling environments, simulation environments, mixed simulation environments, and comprehensive simulation environments.展开更多
Groundwater is the water located beneath the earth＇s surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environ...Groundwater is the water located beneath the earth＇s surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environment, public health, welfare, and long-term economic growth, which affects the daily activities of human beings. In modern urban areas, the primary contaminants of groundwater are artificial products, such as gasoline and diesel. To protect this important water resource, a series of efforts have been exerted, including enforcement and remedial actions. Each year, the TGPC （Texas Groundwater Protection Committee） in US publishes a ＂Joint Groundwater Monitoring and Contamination Report＂ to describe historic and new contamination cases in each county, which is an important data source for the design of prevention strategies. In this paper, a DDM （data dependent modeling） approach is proposed to predict county-level NCC （new contamination cases）. A case study with contamination information from Harris County in Texas was conducted to illustrate the modeling and prediction process with promising results. The one-step prediction error is 1.5%, while the two-step error is 12.1%. The established model can be used at the county-level, state-level, and even at the country-level. Besides, the prediction results could be a reference during decision-making processes.展开更多
An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy developme...An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy development. Some details about how to use the EIOM was discussed. The EIOM was applied to the Changsha City in China. The example results indicate that much useful information related to the environment and the regional economy development can be gained from the solution of the EIOM. Thus, the EIOM can be used as a useful tool for the sustainable development planning including the solid waste management sectors.展开更多
Through careful study, it found that the key and difficult points of affecting and restricting Xi＇an to reach the model city construction standards in provincial and national levels were ＂urban air environment quali...Through careful study, it found that the key and difficult points of affecting and restricting Xi＇an to reach the model city construction standards in provincial and national levels were ＂urban air environment quality standards＂ and ＂water qualification rate of urban water environment function area＂. In order to tackle with the weak links, highlight the important points and focus on the difficult points to strengthen scientific and technological innovation, we actively explored new ideas and ways to resolve the dilemma in meeting the two standards of model city construction, and we managed to put forward the countermeasures to resolve the dilemma through innovating system and mechanism. ＂Place master system＂ should be carded out quickly to meet the ＂urban air environment quality standards＂, while ＂river master system＂ should be implemented as soon as possible to reach the ＂water qualification rate of urban water environment function area＂. The aim of this study was to enhance the qualification rates of the indicators for model city construction to make Xi＇an successfully pass the provincial and national assessment of model city construction through dealing with the weak links to accelerate the realization of becoming model environmental protection city.展开更多
Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after in...Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after independence has resulted into erosion of its communities’ conservation behaviour and attitude. Although many studies assess environmental attitudes, those focussing on African regions or countries using New Environmental Paradigm (NEP) scale are very limited. Such studies in the African context using NEP scale are very important, simply because many people depend on the environment for their livelihood, and in the process they destroy the world’s valued ecosystems including wetlands. This study is meant to fill in the gap using Kilombero valley wetlands in Tanzania as a case. The study used Structural Equation Modelling (SEM) to predict the behaviour of the users based on attitudes, environmental knowledge and awareness. The findings indicate that users of the Kilombero wetlands have a generally positive attitude towards the environment, despite a great degree of variability among the study participants. The study shows also that a certain level of environmental awareness is needed in order to increase people’s knowledge about environmental issues and change their environmental attitudes. The NEP scale does not fully fit into the Tanzanian context, thus suggesting that further research into the adaptation of the scale is needed.展开更多
基金supported in part by the Guangzhou Basic and Applied Basic Research Foundation(2023A04J1740)in part by the Shaanxi Provincial Key Research and Development Program(2023-ZDLGY-33,2022ZDLGY05-03,2022ZDLGY05-04)in part by the Fundamental Research Funds for the Central Universities(XJS220116).
文摘Radio frequency(RF)-based drone identification technologies have the advantages of long effective distances and low environmental dependence,which has become indispensable for drone surveillance systems.However,since drones operate in unlicensed frequency bands,a large number of co-frequency devices exist in these bands,which brings a great challenge to traditional signal identification methods.Deep learning techniques provide a new approach to complete endto-end signal identification by directly learning the distribution of RF data.In such scenarios,due to the complexity and high dynamics of the electromagnetic environments,a massive amount of data that can reflect the various propagation conditions of drone signals is necessary for a robust neural network(NN)for identifying drones.In reality,signal acquisition and labeling that meet the above requirements are too costly to implement.Therefore,we propose a virtual electromagnetic environment modeling based data augmentation(DA)method to improve the diversity of drone signal data.The DA method focuses on simulating the spectrograms of drone signals transmitted in real-world environments and randomly generates extra training data in each training epoch.Furthermore,considering the limited processing capability of RF receivers,we modify the original YOLOv5s model to a more lightweight version.Without losing the identification performance,more hardware-friendly designs are applied and the number of parameters decreases about 10-fold.For performance evaluation,we utilized a universal software radio peripheral(USRP)X310 platform to collect RF signals of four drones in an anechoic chamber and a practical wireless scenario.Experiment results reveal that the NN trained with augmented data performs as well as that trained with practical data in the complex electromagnetic environment.
基金supported by the National Natural Science Foundation of China(62027809,U2268206,T2222015,U2468202).
文摘The integration of Global Navigation Satellite System(GNSS)technology into railway train control systems is a crucial step toward achieving the vision of a digital railway.Traditional train control systems undergo extensive in-house tests and prolonged field tests for certification and approval before operational deployment,leading to high costs,delays,and operational disruptions.This paper introduces a GNSS-based train control localization framework which eliminates the need for on-site testing by leveraging train movement dynamics and 3D environment modeling to create a zero on-site testing platform.The proposed framework simulates train movement and the surrounding 3D environment using collected railway line location data and environmental attributes to generate realistic multipath signals and obscuration effects.This approach enables comprehensive laboratory-based case studies for train localization,reducing the huge amount test of needed for physical field trials.The framework is established in house,using the data collected at the Test Base of China Academy of Railway Sciences(Circular Railway).Results from the open area and cutting environment tests demonstrate high localization accuracy repeatability within the simulated environment,validating the feasibility and effectiveness of zero on-site testing for GNSS-based train control systems.This research highlights the potential of GNSS simulation platforms in enhancing cost efficiency,operational safety,and accuracy for future digital railways.
基金Shanghai Leading Academic Discipline Project (T0502)Shanghai Municipal Educational Commission Project (05EZ32).
文摘With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects （alternatives） for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports＇ information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals （WSI）, the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them.
基金This research was supported by the Natural Science Foundation of China(Grant No.41907188)Natural Science Foundation of Shaanxi Province,China(Grant No.2019JQ-386)the China Postdoctoral Science Foundation(Grant No.2019M653658).
文摘Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).
文摘More effective environmental pollution control and management are needed due to the increasing environ-mental impacts from a range of human activities and the growing public demands for a better living environment. Urban air pollution is a serious environmental issue that poses adverse impacts on the health of people and the environment in most metropolitan areas. In this paper,we propose a geoinformatics augmented framework of environmental modelling and information sharing for supporting effective urban air pollution control and management. This framework is out-lined in terms of its key components and processes including: 1) an integrated,adaptive network of sensors for envi-ronmental monitoring; 2) a set of distributed,interoperable databases for data management; 3) a set of intelligent,robust algorithms and models for environmental modelling; 4) a set of flexible,efficient user interfaces for data access and in-formation sharing; and 5) a reliable,high capacity,high performance computing and communication infrastructure for integrating and supporting other framework components and processes.
基金Under the auspices of Major State Basic Research Development Program of China (No. 2004CB418507)
文摘Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a mining city in Northeast China,were studied. The results showed that,due to scale effect,the drainage of three important industrial wastewater pollutants(COD,NH3-N and petroleum) increased 8505t,671t and 384t,respectively,and due to structure effect,those pollutants drainage increased 3996t,174t and 120t from 2001 to 2006. While due to technological effect,the drainage of COD,NH3-N and petroleum reduced 4452t,458t and 331t,and due to cross effect,those pollutants drainage reduced 7270t,575t and 476t simultaneously. Meantime,the relationships between household consumption structure and domestic sewage discharge were analyzed,and domestic sewage discharges in different income levels were also compared. The results showed that,the domestic sewage discharges would increase 376t with 1000 yuan(RMB) increased in the traffic and communication consumption,and they would be 344t,219t,428t,1873t,respectively,in housing consumption,food consumption,medical consumption,miscellaneous commodity consumption. The proportion of domestic sewage discharge increased for high income residents significantly,but reduced for lower income residents. The industrial wastewater pollutants drainage tends to be reduced by technical progress,while domestic sewage discharge will be a more important factor for urban water environment quality.
基金supported by the Aeronautical Science Foundation of China(No.2012ZD51043)‘‘Fanzhou’’ Youth Scientifc Funds(No.20100504)
文摘The structure and characteristics of a large multi-parameter environmental simulation cabin are introduced.Due to the diffculties of control methods and the easily damaged characteristics,control systems for the large multi-parameter environmental simulation cabin are diffcult to be controlled quickly and accurately with a classical PID algorithm.Considering the dynamic state characteristics of the environmental simulation test chamber,a lumped parameter model of the control system is established to accurately control the multiple parameters of the environmental chamber and a fuzzy control algorithm combined with expert-PID decision is introduced into the temperature,pressure,and rotation speed control systems.Both simulations and experimental results have shown that compared with classical PID control,this fuzzy-expert control method can decrease overshoot as well as enhance the capacity of anti-dynamic disturbance with robustness.It can also resolve the contradiction between rapidity and small overshoot,and is suitable for application in a large multi-parameter environmental simulation cabin control system.
基金The National Natural Science Foundation of China under contract No.NSFC31702343the Science Foundation of Shanghai under contract No.13ZR1419700+4 种基金the Innovation Program of Shanghai Municipal Education Commission under contract No.13YZ091the National High-tech R&D Program of China(863 Program)under contract No.2012AA092303the Funding Program for Outstanding Dissertations in Shanghai Ocean Universitythe Funding Scheme for Training Young Teachers in Shanghai Colleges and the Shanghai Leading Academic Discipline Project(Fisheries Discipline)Involvement of Chen Yong was supported by SHOU International Center for Marine Studies and Shanghai 1000 Talent Program
文摘The southern Patagonian stock（SPS） of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production（EDSP） model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors（favorable spawning habitat areas with sea surface temperature of 16–18°C） were assumed to be closely associated with carrying capacity（K） in the EDSP model. Deviance Information Criterion（DIC） values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield（MSY） from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F（0.1） and F（MSY）. Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management.
基金supported by the National Natural Science Foundation of China (10372026 and 10772751)Shanghai Leading Academic Discipline Project (B 112).
文摘To investigate tumor-induced angiogenesis under the influence of the mechanical environments inside and outside the tumor, mathematical model of tumor angiogenesis was developed. In the model, extra-cellular matrix （ECM） was treated as a thin plane. The displacement of ECM is obtained from the force balance equation consisted of the ECs traction, the ECM visco-elastic forces and the exter- nal forces. Simulation results show that a layered capillary network is obtained with a well vascularized region at the periphery of the tumor. The present model can be used as a valid theoretical method in the basic researches in tumorinduced angiogenesis.
基金supported by the Aeronautical Science Foun-dation of China(No.2012XX51043)‘‘Fanzhou’’Youth Scientific Funds of China(No.20100504)
文摘A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic control of the temperature–pressure two-parameter and overcome the control difficulties inherent to a large inertia lag link with a complex control system which is composed of turbine refrigeration device, vacuum device and liquid nitrogen cooling device. The system includes multi-parameter decoupling of the cabin itself to avoid equipment damage of air refrigeration turbine caused by improper operation. Based on analysis of the dynamic characteristics and modeling for variations in temperature, pressure and rotation speed, an intelligent controller was implemented that includes decoupling and fuzzy arithmetic combined with an expert PID controller to control test parameters by decoupling and slope tracking control strategy. The control system employed centralized management in an open industrial ethernet architecture with an industrial computer at the core. The simulation and field debugging and running results show that this method can solve the problems of a poor anti-interference performance typical for a conventional PID and overshooting that can readily damage equipment. The steady-state characteristics meet the system requirements.
文摘JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.
文摘This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform. Based on the traditional environmental “Kuznets” model, the factor of environmental tax is added to verify the effect of environmental governance of environmental tax. The results show that: 1) the improvement of sulfur dioxide emission charge standard can effectively inhibit industrial sulfur dioxide emission, which verifies the existence of environmental effect of pollution levy policies</span><span style="font-family:"">.</span><span style="font-family:""> 2) The improvement of sewage charge standard has better inhibitory effect on sulfur dioxide emission per unit GDP than on sulfur dioxide emission</span><span style="font-family:"">.</span><span style="font-family:""> 3) There is regional heterogeneity in the “emission reduction” effect of sulfur dioxide emission charges in the eastern, central and western regions of China. Pollutants should be taxed differently according to regional differences</span><span style="font-family:"">.</span><span style="font-family:""> 4) Economic growth and sulfur dioxide emission show an inverted “U” shape, China is still in the stage before the inflection point of EKC. Economic growth still takes environmental damage as the cost, and the “emission reduction” effect of technological progress is not ideal, which reveals the urgency of increasing technological development in the field of green environmental protection under the current situation.
基金Supported by the NNSF of China(30570426)Fok Ying Tung Education Foundation(101004)the Youth Foundation of Educational Department of Hunan Province in China(05B007).
文摘The purpose of this paper is to analyse mathematical models used in environmental modelling. Following a brief survey of the development in modelling scale- and time-dependent dispersion processes in the environment, this paper compares three similarity solutions, one of which is a solution of the generalized Feller equation （GF） with fractal parameters, and the other two for the newly-developed generalized Fokker-Planck equation （GFP）. The three solutions are derived with parameters having physical significance. Data from field experiments are used to verify the solutions. The analyses indicate that the solutions of both GF and GFP represent the physically meaningful natural processes, and simulate the realistic shapes of tracer breakthrough curves.
基金funded by National Research Council of Thailand(NRCT)and Khon Kaen University:N42A650291.
文摘The motive of these investigations is to provide the importance and significance of the fractional order(FO)derivatives in the nonlinear environmental and economic(NEE)model,i.e.,FO-NEE model.The dynamics of the NEE model achieves more precise by using the form of the FO derivative.The investigations through the non-integer and nonlinear mathematical form to define the FO-NEE model are also provided in this study.The composition of the FO-NEEmodel is classified into three classes,execution cost of control,system competence of industrial elements and a new diagnostics technical exclusion cost.The mathematical FO-NEE system is numerically studied by using the artificial neural networks(ANNs)along with the Levenberg-Marquardt backpropagation method(ANNs-LMBM).Three different cases using the FO derivative have been examined to present the numerical performances of the FO-NEE model.The data is selected to solve the mathematical FO-NEE system is executed as 70%for training and 15%for both testing and certification.The exactness of the proposed ANNs-LMBM is observed through the comparison of the obtained and the Adams-Bashforth-Moulton database results.To ratify the aptitude,validity,constancy,exactness,and competence of the ANNs-LMBM,the numerical replications using the state transitions,regression,correlation,error histograms and mean square error are also described.
文摘A brief review of the basic terminology on simulation, simulation life-cycle activities such as model-based activities, behavior-oriented activities, and quality assurance activities is given. Then, the challenges and opportunities for the advancement of the state-of-the-art in simulation environments are discussed under the following headings: modelling environments, simulation environments, mixed simulation environments, and comprehensive simulation environments.
文摘Groundwater is the water located beneath the earth＇s surface in the soil pore spaces and in the fractures of rock formations. As one of the most important natural resources, groundwater is associated with the environment, public health, welfare, and long-term economic growth, which affects the daily activities of human beings. In modern urban areas, the primary contaminants of groundwater are artificial products, such as gasoline and diesel. To protect this important water resource, a series of efforts have been exerted, including enforcement and remedial actions. Each year, the TGPC （Texas Groundwater Protection Committee） in US publishes a ＂Joint Groundwater Monitoring and Contamination Report＂ to describe historic and new contamination cases in each county, which is an important data source for the design of prevention strategies. In this paper, a DDM （data dependent modeling） approach is proposed to predict county-level NCC （new contamination cases）. A case study with contamination information from Harris County in Texas was conducted to illustrate the modeling and prediction process with promising results. The one-step prediction error is 1.5%, while the two-step error is 12.1%. The established model can be used at the county-level, state-level, and even at the country-level. Besides, the prediction results could be a reference during decision-making processes.
文摘An environmental input output model (EIOM) was introduced to the regional solid waste management sectors, which can reflect the direct and indirect relations between the environment and the regional economy development. Some details about how to use the EIOM was discussed. The EIOM was applied to the Changsha City in China. The example results indicate that much useful information related to the environment and the regional economy development can be gained from the solution of the EIOM. Thus, the EIOM can be used as a useful tool for the sustainable development planning including the solid waste management sectors.
文摘Through careful study, it found that the key and difficult points of affecting and restricting Xi＇an to reach the model city construction standards in provincial and national levels were ＂urban air environment quality standards＂ and ＂water qualification rate of urban water environment function area＂. In order to tackle with the weak links, highlight the important points and focus on the difficult points to strengthen scientific and technological innovation, we actively explored new ideas and ways to resolve the dilemma in meeting the two standards of model city construction, and we managed to put forward the countermeasures to resolve the dilemma through innovating system and mechanism. ＂Place master system＂ should be carded out quickly to meet the ＂urban air environment quality standards＂, while ＂river master system＂ should be implemented as soon as possible to reach the ＂water qualification rate of urban water environment function area＂. The aim of this study was to enhance the qualification rates of the indicators for model city construction to make Xi＇an successfully pass the provincial and national assessment of model city construction through dealing with the weak links to accelerate the realization of becoming model environmental protection city.
文摘Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after independence has resulted into erosion of its communities’ conservation behaviour and attitude. Although many studies assess environmental attitudes, those focussing on African regions or countries using New Environmental Paradigm (NEP) scale are very limited. Such studies in the African context using NEP scale are very important, simply because many people depend on the environment for their livelihood, and in the process they destroy the world’s valued ecosystems including wetlands. This study is meant to fill in the gap using Kilombero valley wetlands in Tanzania as a case. The study used Structural Equation Modelling (SEM) to predict the behaviour of the users based on attitudes, environmental knowledge and awareness. The findings indicate that users of the Kilombero wetlands have a generally positive attitude towards the environment, despite a great degree of variability among the study participants. The study shows also that a certain level of environmental awareness is needed in order to increase people’s knowledge about environmental issues and change their environmental attitudes. The NEP scale does not fully fit into the Tanzanian context, thus suggesting that further research into the adaptation of the scale is needed.
