As environmental pollutants pose a serious threat to socioeconomic and environmental health,the development of simple,efficient,accurate and costeffective methods for pollution monitoring and control remains a major c...As environmental pollutants pose a serious threat to socioeconomic and environmental health,the development of simple,efficient,accurate and costeffective methods for pollution monitoring and control remains a major challenge,but it is an unavoidable issue.In the past decade,the artificial nanozymes have been widely used for environmental pollutant monitoring and control,because of their low cost,high stability,easy mass production,etc.However,the conventional nanozyme technology faces significant challenges in terms of difficulty in regulating the exposed crystal surface,complex composition,low catalytic activity,etc.In contrast,the emerging single-atom nanozymes(SANs)have attracted much attention in the field of environmental monitoring and control,due to their multiple advantages of atomically dispersed active sites,high atom utilization efficiency,tunable coordination environment,etc.To date,the insufficient efforts have been made to comprehensively characterize the applications of SANs in the monitoring and control of environmental pollutants.Building on the recent advances in the field,this review systematically summarizes the main synthesis methods of SANs and highlights their advances in the monitoring and control of environmental pollutants.Finally,we critically evaluate the limitations and challenges of SANs,and provide the insights into their future prospects for the monitoring and control of environmental pollutants.展开更多
As a major global public health issue,tuberculosis is closely related to multiple socio-ecological factors in its epidemiological patterns~([1]).China,as a high-burden country for tuberculosis,exhibits regional variat...As a major global public health issue,tuberculosis is closely related to multiple socio-ecological factors in its epidemiological patterns~([1]).China,as a high-burden country for tuberculosis,exhibits regional variations in the distribution of the tuberculosis epidemic.To enhance the efficiency of prevention and control,its strategies are undergoing a transition toward regionally differentiated approaches~([2]).展开更多
Purpose:This study provides a comprehensive bibliometric analysis of the environmental management control tools literature.It seeks to summarize this body of literature’s growth and identify the most influential auth...Purpose:This study provides a comprehensive bibliometric analysis of the environmental management control tools literature.It seeks to summarize this body of literature’s growth and identify the most influential authors,journals,and articles in this field.The main objective of this article is to determine which tools are most prominent in the literature.Methodology/approach:The study examined 541 articles published in 126 academically indexed journals in the Scopus database.The analyzed timeframe covers the period from 2011 to 2023.We used VOSviewer software for statistical calculations to map the collaborations among authors and journals and to develop a conceptual and intellectual map of the field.Results:Our findings show that the literature on environmental management control tools is flourishing.The authors who dominated this period are mainly Schaltegger,Sala,and Ulgiati.The Journal of Cleaner Production is the primary source of publications,with an astounding 241 documents.The United States attained the leading position in terms of publication with 86 documents,which explains its willingness to collaborate with other countries,followed by China and Australia with 70 and 66 papers,respectively.Finally,bibliometric analysis shows that“life cycle assessment”,“cost-benefit analysis”,and“sustainability reporting”are the most prominent tools in research on this topic.Originality/value:This article provides several starting points for researchers and practitioners investigating environmental management control tools.It contributes to broadening the field’s vision and then offers recommendations for future studies.展开更多
Abstract This paper conducts a simulation study of a novel aircraft environmental control system based on membrane dehumidification (MD-ECS), and compares the system with the up-to-date four-wheel high pressure de-w...Abstract This paper conducts a simulation study of a novel aircraft environmental control system based on membrane dehumidification (MD-ECS), and compares the system with the up-to-date four-wheel high pressure de-water system (4WHPDW-ECS). Mathematical models for the two sys- tems are established, and a system simulation using a numerical technique is performed to analyze and compare the cooling performance of the two systems. Simulation results show that the cooling capacity of MD-ECS is much higher than that of 4WHPDW-ECS under the same working conditions, indicating that the novel system is theoretically feasible and promising. The effects of the sweep ratio of the membrane dehumidifier on the dehumidification and cooling performance of the system is also investigated.展开更多
Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water i...Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.展开更多
Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering i...Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering is a complex molecular process that involves a multitude of factors.Little is known about the molecular mechanisms in the wheat genome,although progress has been made in rice.Here we review the developmental characteristics of tillers and summarize current knowledge of the roles of endogenous and environmental factors in wheat tillering.We propose directions for future studies and advanced technologies to be used for gene identification and functional studies.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
Among the promising application of autonomous surface vessels(ASVs)is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform,a broken ship,or a ship in port areas.Consid...Among the promising application of autonomous surface vessels(ASVs)is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform,a broken ship,or a ship in port areas.Considering the real conditions and operations of maritime practice,this paper proposes a multi-agent control algorithm to manipulate a ship to a desired position with a desired heading and velocity under the environmental disturbances.The control architecture consists of a supervisory controller in the higher layer and tug controllers in the lower layer.The supervisory controller allocates the towing forces and angles between the tugs and the ship by minimizing the error in the position and velocity of the ship.The weight coefficients in the cost function are designed to be adaptive to guarantee that the towing system functions well under environmental disturbances,and to enhance the efficiency of the towing system.The tug controller provides the forces to tow the ship and tracks the reference trajectory that is computed online based on the towing angles calculated by the supervisory controller.Simulation results show that the proposed algorithm can make the two autonomous tugs cooperatively tow a ship to a desired position with a desired heading and velocity under the(even harsh)environmental disturbances.展开更多
Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidit...Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidity,light intensity,and CO 2 concentration.Due to the complex coupled correlations,it is a challenge to achieve coordination control of greenhouse environmental factors.This paper proposes a model-free coordination control approach for greenhouse environmental factors based on Q-learning.Coordination control policy is found through systematic interaction with the dynamic environment to achieve optimal control for greenhouse climate with the control cost constraints.In order to decrease systematic trial-and-error risk and reduce the computational complexity in Q-learning algorithm,case-based reasoning (CBR) is seamlessly incorporated into the Q-learning process.The experimental results demonstrate that this approach is practical,highly effective and efficient.展开更多
The design and assembly of environmental monitoring and control system for large-scale pig house with fermentation bed helped to solve the problem of environmental automatic control in piggery.The sensors would monito...The design and assembly of environmental monitoring and control system for large-scale pig house with fermentation bed helped to solve the problem of environmental automatic control in piggery.The sensors would monitor the temperature,humidity,light,wind direction,wind speed,CO2,NH3and other parameters.On-line real-time data collection was achieved.The expert system was constructed to control the temperature in piggery below 30℃,to control the air and mattress humidities higher than 65%.Under the conditions of different season or different wind speed,even in day and night,the control actuators were different.The actuators included fanning wet curtain,lighting,micro spraying,spraying,propeller fan,electric aluminum alloy shutter and spraying systems on the roof.The actuators were integrated,and they control the piggery environment simultaneously.The system also designed the remote video monitor interface,parameter-monitoring curved interface and operation interface,which provided a good man-machine interface.展开更多
Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) stand...Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth.展开更多
Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice fi...Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field’s environmental contamination was discussed. Meanwhile, some suggestions were proposed.展开更多
[Objeetive] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology. [Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0, and the controlling units wi...[Objeetive] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology. [Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0, and the controlling units with response of water-land were divided according to the riv- er monitoring sections of Xuchang City; considering the wastewater entering the river and the water from its upper reach, the runoff of controlling sections in the driest month ( with guarantee rate of 90% ) was calculated by means of isoline, runoff coefficient and hydrologic analogy method, and the calculated value of Gaocun Bridge section in Linying was contrasted with the measured value in 2010. [Result] The results showed that the cal- culated value and measured value of Gaecun Bridge section in Linying in the driest month of 2010 were 6.03 and 5.93 m^3/s respectively, with relative error of 1.69%, which revealed that the result of calculated runoff was reasonable. [ Conclusion] The way to divide controlling units was reason- able, and the calculation result of runoff was accurate and can meet the precision of water environment capacity calculation.展开更多
Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental poll...Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental pollution problem generated by dairy farming in Inner Mongolia and its cause were analyzed,and prevention and control measures were put forward. The research result showed that weak technology support of environmental treatment and environmental-protection awareness of dairy farmer and bad application effect of pollution control technology caused by lower education degree of dairy farmer were main reasons for environmental pollution problem. We should develop dairy circular economy,advocate a moderate scale,scientifically breed,and enhance training of pollution control technology and propaganda to protect environment.展开更多
The continuous progress of industrialization is a fundamental cause of China’s increasingly severe environmental pollution problem.Improving the efficiency of industrial pollution control is an inevitable choice to e...The continuous progress of industrialization is a fundamental cause of China’s increasingly severe environmental pollution problem.Improving the efficiency of industrial pollution control is an inevitable choice to effectively decrease pollution emissions,thus winning the battle of pollution prevention and control.In this paper,we used the stochastic frontier analysis(SFA)model to measure the provincial efficiency of industrial pollution control based on the input and output data of industrial pollution control of 29 administrative provinces in China from 2000 to 2017.On this basis,a spatial econometric model was used to explore the influence of environmental regulation intensity on the efficiency of industrial pollution control.In addition,the spatial spillover effect of pollution reduction was thoroughly examined.The results show that:(1)The efficiency of industrial pollution control in China has improved year by year,but the overall efficiency is still low,with the average value increasing from 0.165 in 2000 to 0.309 in 2017.Furthermore,there is significant regional heterogeneity with the highest efficiency level in the east and lowest efficiency level in the west.(2)By increasing the financial and material input,the efficiency of industrial pollution control has increased.However,the increase of human input has not been so helpful.(3)The global Moran’s I index is significantly greater than zero,indicating a strong spatial correlation and agglomeration in the efficiency of industrial pollution control,which is reflected in high-high agglomeration in the eastern region and low-low agglomeration in the western region.(4)Stringent environmental regulation has a positive effect on improving the efficiency of industrial pollution control.It also imposes a positive spatial spillover effect,indicating a strategic interaction and coordination of regional pollution control.In line with this,related proposals have been made to optimize the investment structure for environmental pollution control,establish a flow mechanism for the factor market,and strengthen the environmental responsibility awareness of state-owned enterprises.On this basis,we expect to provide a policy for improving the efficiency of industrial pollution control and promoting regional joint pollution control in China.展开更多
Finding the optimal control is of importance to quantum metrology under a noisy environment.In this paper,we tackle the problem of finding the optimal control to enhance the performance of quantum metrology under an a...Finding the optimal control is of importance to quantum metrology under a noisy environment.In this paper,we tackle the problem of finding the optimal control to enhance the performance of quantum metrology under an arbitrary non-Markovian bosonic environment.By introducing an equivalent pseudomode model,the non-Markovian dynamic evolution is reduced to a Lindblad master equation,which helps us to calculate the gradient of quantum Fisher information and perform the gradient ascent algorithm to find the optimal control.Our approach is accurate and circumvents the need for the Born-Markovian approximation.As an example,we consider the frequency estimation of a spin with pure dephasing under two types of non-Markovian environments.By maximizing the quantum Fisher information at a fixed evolution time,we obtain the optimal multi-axis control,which results in a notable enhancement in quantum metrology.The advantage of our method lies in its applicability to the arbitrary non-Markovian bosonic environment.展开更多
To effectively select risk control schemes in uncertain environments,this paper has proposed an analysis and evaluation method based on the fuzzy comprehensive evaluation method.Firstly,enterprises have adopted the br...To effectively select risk control schemes in uncertain environments,this paper has proposed an analysis and evaluation method based on the fuzzy comprehensive evaluation method.Firstly,enterprises have adopted the brainstorming method and the Delphi method to identify risks in engineering projects,and organized the identified risks in the form of checklists to facilitate further analysis.Secondly,the fuzzy comprehensive evaluation theory was introduced to determine the comparison matrix of each risk factor and its weight.Furthermore,the top five risk factors in terms of weight ranking were taken as the evaluation factors for the selection of risk control plans.The plans were scored through the weighted scoring method,and the optimal risk control plan was determined based on the score.Finally,the feasibility of the proposed selection technology was verified through A research example of the risk control plan assessment for the construction project of Enterprise A.展开更多
Objective To investigate the association between autism and prenatal environmental risk factors.Methods A case-control study was conducted among 193 children with autism from the specialeducational schools and 733 typ...Objective To investigate the association between autism and prenatal environmental risk factors.Methods A case-control study was conducted among 193 children with autism from the specialeducational schools and 733 typical development controls matched by age and gender by usingquestionnaire in Tianjin from 2007 to 2012. Statistical analysis included quick unbiased efficientstatistical tree (QUEST) and logistic regression in SPSS 20.0.Results There were four predictors by QUEST and the logistic regression analysis, maternal airconditioner use during pregnancy (OR=0.316, 95% CI: 0.215-0.463) was the single first-level node(χ2=50.994, P=0.000); newborn complications (OR=4.277, 95% CI: 2.314-7.908) and paternalconsumption of freshwater fish (OR=0.383, 95% CI: 0.256-0.573) were second-layer predictors(χ2=45.248, P=0.000; χ2=24.212, P=0.000); and maternal depression (OR=4.822, 95% CI: 3.047-7.631)was the single third-level predictor (χ2=23.835, P=0.000). The prediction accuracy of the tree was 89.2%.Conclusion The air conditioner use during pregnancy and paternal freshwater fish diet might bebeneficial for the prevention of autism, while newborn complications and maternal depression might bethe risk factors.展开更多
Traditional two-pass weed management strategies need to be compared with new strategies in glyphosate/dicamba-resistant soybean. Weed control, soybean yield, partial profitability and environmental impact (EI) were ev...Traditional two-pass weed management strategies need to be compared with new strategies in glyphosate/dicamba-resistant soybean. Weed control, soybean yield, partial profitability and environmental impact (EI) were evaluated in glyphosate/dicamba-resistant soybean using dicamba applied alone or in a tank-mix with dimethenamid-P applied preemergence (PRE). Trials were conducted at three locations during 2014 and 2015. Several PRE herbicides provided excellent control of broadleaf and grass weeds. Dicamba provided > 91% control of broadleaf weeds, and the addition of dimethenamid-P improved grass control. All weed species at the trial locations were controlled > 94% following a postemergence (POST) application of glyphosate. Weed interference reduced soybean seed yield 33% where no herbicide was applied. A single POST application of glyphosate had the lowest EI. Several treatments improved early-season weed control and reduced early-season weed density and biomass compared to glyphosate and had similar EI values. In this study, there was no benefit to yield or partial profit by including a PRE herbicide for weed management;however, the inclusion of multiple modes-of-action in a herbicide program may reduce the selection for herbicide-resistant weeds.展开更多
基金supported by the National Natural Science Foundation of China(22422604,32472435)the National Key Research and Development Program of China(2021YFD1700300)+1 种基金the Agricultural Science and Technology Innovation Program of CAAS(CAAS-ASTIP-IQSTAP-04)the State Key Laboratory of Analytical Chemistry for Life Science。
文摘As environmental pollutants pose a serious threat to socioeconomic and environmental health,the development of simple,efficient,accurate and costeffective methods for pollution monitoring and control remains a major challenge,but it is an unavoidable issue.In the past decade,the artificial nanozymes have been widely used for environmental pollutant monitoring and control,because of their low cost,high stability,easy mass production,etc.However,the conventional nanozyme technology faces significant challenges in terms of difficulty in regulating the exposed crystal surface,complex composition,low catalytic activity,etc.In contrast,the emerging single-atom nanozymes(SANs)have attracted much attention in the field of environmental monitoring and control,due to their multiple advantages of atomically dispersed active sites,high atom utilization efficiency,tunable coordination environment,etc.To date,the insufficient efforts have been made to comprehensively characterize the applications of SANs in the monitoring and control of environmental pollutants.Building on the recent advances in the field,this review systematically summarizes the main synthesis methods of SANs and highlights their advances in the monitoring and control of environmental pollutants.Finally,we critically evaluate the limitations and challenges of SANs,and provide the insights into their future prospects for the monitoring and control of environmental pollutants.
文摘As a major global public health issue,tuberculosis is closely related to multiple socio-ecological factors in its epidemiological patterns~([1]).China,as a high-burden country for tuberculosis,exhibits regional variations in the distribution of the tuberculosis epidemic.To enhance the efficiency of prevention and control,its strategies are undergoing a transition toward regionally differentiated approaches~([2]).
文摘Purpose:This study provides a comprehensive bibliometric analysis of the environmental management control tools literature.It seeks to summarize this body of literature’s growth and identify the most influential authors,journals,and articles in this field.The main objective of this article is to determine which tools are most prominent in the literature.Methodology/approach:The study examined 541 articles published in 126 academically indexed journals in the Scopus database.The analyzed timeframe covers the period from 2011 to 2023.We used VOSviewer software for statistical calculations to map the collaborations among authors and journals and to develop a conceptual and intellectual map of the field.Results:Our findings show that the literature on environmental management control tools is flourishing.The authors who dominated this period are mainly Schaltegger,Sala,and Ulgiati.The Journal of Cleaner Production is the primary source of publications,with an astounding 241 documents.The United States attained the leading position in terms of publication with 86 documents,which explains its willingness to collaborate with other countries,followed by China and Australia with 70 and 66 papers,respectively.Finally,bibliometric analysis shows that“life cycle assessment”,“cost-benefit analysis”,and“sustainability reporting”are the most prominent tools in research on this topic.Originality/value:This article provides several starting points for researchers and practitioners investigating environmental management control tools.It contributes to broadening the field’s vision and then offers recommendations for future studies.
基金support from Aeronautical Science Foundation of China(No.2011ZC09006)
文摘Abstract This paper conducts a simulation study of a novel aircraft environmental control system based on membrane dehumidification (MD-ECS), and compares the system with the up-to-date four-wheel high pressure de-water system (4WHPDW-ECS). Mathematical models for the two sys- tems are established, and a system simulation using a numerical technique is performed to analyze and compare the cooling performance of the two systems. Simulation results show that the cooling capacity of MD-ECS is much higher than that of 4WHPDW-ECS under the same working conditions, indicating that the novel system is theoretically feasible and promising. The effects of the sweep ratio of the membrane dehumidifier on the dehumidification and cooling performance of the system is also investigated.
基金supported by the National Natural Sciences Foundation of China(No.51309216)the Ministry of Sciences and Technology of the People’s Republic of China(No.2012ZX07408-002)
文摘Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.
基金supported by the Major Research Plan of the National Natural Science Foundation of China (91935302)the National Natural Science Foundation of China (31971812)Major Basic Research Project of Shandong Natural Science Foundation (ZR2019ZD15)。
文摘Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering is a complex molecular process that involves a multitude of factors.Little is known about the molecular mechanisms in the wheat genome,although progress has been made in rice.Here we review the developmental characteristics of tillers and summarize current knowledge of the roles of endogenous and environmental factors in wheat tillering.We propose directions for future studies and advanced technologies to be used for gene identification and functional studies.
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supported by the China Scholarship Council(201806950080)the Researchlab Autonomous Shipping(RAS)of Delft University of Technology,and the INTERREG North Sea Region Grant“AVATAR”funded by the European Regional Development Fund.
文摘Among the promising application of autonomous surface vessels(ASVs)is the utilization of multiple autonomous tugs for manipulating a floating object such as an oil platform,a broken ship,or a ship in port areas.Considering the real conditions and operations of maritime practice,this paper proposes a multi-agent control algorithm to manipulate a ship to a desired position with a desired heading and velocity under the environmental disturbances.The control architecture consists of a supervisory controller in the higher layer and tug controllers in the lower layer.The supervisory controller allocates the towing forces and angles between the tugs and the ship by minimizing the error in the position and velocity of the ship.The weight coefficients in the cost function are designed to be adaptive to guarantee that the towing system functions well under environmental disturbances,and to enhance the efficiency of the towing system.The tug controller provides the forces to tow the ship and tracks the reference trajectory that is computed online based on the towing angles calculated by the supervisory controller.Simulation results show that the proposed algorithm can make the two autonomous tugs cooperatively tow a ship to a desired position with a desired heading and velocity under the(even harsh)environmental disturbances.
基金supported by National Natural Science Foundationof China(No.60775014)
文摘Optimal control of greenhouse climate is one of the key techniques in digital agriculture.Greenhouse climate,a nonlinear and uncertain system,consists of several major environmental factors such as temperature,humidity,light intensity,and CO 2 concentration.Due to the complex coupled correlations,it is a challenge to achieve coordination control of greenhouse environmental factors.This paper proposes a model-free coordination control approach for greenhouse environmental factors based on Q-learning.Coordination control policy is found through systematic interaction with the dynamic environment to achieve optimal control for greenhouse climate with the control cost constraints.In order to decrease systematic trial-and-error risk and reduce the computational complexity in Q-learning algorithm,case-based reasoning (CBR) is seamlessly incorporated into the Q-learning process.The experimental results demonstrate that this approach is practical,highly effective and efficient.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303094)International Science and Technology Cooperation Project of China(2012DFA31120)National Key Technology Research and Development Program(2012BAD14B15)
文摘The design and assembly of environmental monitoring and control system for large-scale pig house with fermentation bed helped to solve the problem of environmental automatic control in piggery.The sensors would monitor the temperature,humidity,light,wind direction,wind speed,CO2,NH3and other parameters.On-line real-time data collection was achieved.The expert system was constructed to control the temperature in piggery below 30℃,to control the air and mattress humidities higher than 65%.Under the conditions of different season or different wind speed,even in day and night,the control actuators were different.The actuators included fanning wet curtain,lighting,micro spraying,spraying,propeller fan,electric aluminum alloy shutter and spraying systems on the roof.The actuators were integrated,and they control the piggery environment simultaneously.The system also designed the remote video monitor interface,parameter-monitoring curved interface and operation interface,which provided a good man-machine interface.
基金supported by School of Social and Environmental Development,National Institute of Development Administration,Bangkok,Thailand[grant date:8 August 2012]
文摘Projections for 20 years of economic growth and change in the structure of the Thai economy were made for 180 sectors using a computable general equilibrium(CGE) model to compare the following four scenarios:(1) standard growth with infinite supply of factors,(2) finite land supply,(3) fixed use of agricultural chemicals,and(4) combined finite land supply with fixed use of agricultural chemicals.The computable projections suggest that the economic cost of hypothetical environmental control in agriculture is small and further weakened by urbanization.The computed structural development points to efficiency improvements specific to sectors to return the economy to balanced growth.
基金This study was supported by National Natural Science Foundation of China (30270770) Foundation for Achievement Transfer (02EFN214301156) and PPI/PPIC-China Cooperation Project (HN-13).
文摘Development and use of controlled release fertilizer (CRF) in southern China, potential advantages of CRF in increasing rice yield and nutrient use efficiency were introduced, as well as its role of minimizing rice field’s environmental contamination was discussed. Meanwhile, some suggestions were proposed.
文摘[Objeetive] We aimed to calculate the flow of controlling units in a small watershed based on GIS technology. [Method] Hydrologic analysis on Qingyi River was conducted by using ArcGIS9.0, and the controlling units with response of water-land were divided according to the riv- er monitoring sections of Xuchang City; considering the wastewater entering the river and the water from its upper reach, the runoff of controlling sections in the driest month ( with guarantee rate of 90% ) was calculated by means of isoline, runoff coefficient and hydrologic analogy method, and the calculated value of Gaocun Bridge section in Linying was contrasted with the measured value in 2010. [Result] The results showed that the cal- culated value and measured value of Gaecun Bridge section in Linying in the driest month of 2010 were 6.03 and 5.93 m^3/s respectively, with relative error of 1.69%, which revealed that the result of calculated runoff was reasonable. [ Conclusion] The way to divide controlling units was reason- able, and the calculation result of runoff was accurate and can meet the precision of water environment capacity calculation.
文摘Environmental pollution problem generated in dairy farming process is the bottleneck restricting development of animal husbandry. By using the investigation data from dairy farmers of Inner Mongolia,environmental pollution problem generated by dairy farming in Inner Mongolia and its cause were analyzed,and prevention and control measures were put forward. The research result showed that weak technology support of environmental treatment and environmental-protection awareness of dairy farmer and bad application effect of pollution control technology caused by lower education degree of dairy farmer were main reasons for environmental pollution problem. We should develop dairy circular economy,advocate a moderate scale,scientifically breed,and enhance training of pollution control technology and propaganda to protect environment.
基金National Natural Science Foundation of China:The enhancing potential and realizing paths of China’s industrial total factor productivity:A perspective of energy price distortion correction[Grants number.71774122]China Postdoctoral Science Foundation:Research on the Emission Reduction Effect Evaluation and Mechanism of China’s Low-Carbon City Pilot Policies[Grants number.2019M662721].
文摘The continuous progress of industrialization is a fundamental cause of China’s increasingly severe environmental pollution problem.Improving the efficiency of industrial pollution control is an inevitable choice to effectively decrease pollution emissions,thus winning the battle of pollution prevention and control.In this paper,we used the stochastic frontier analysis(SFA)model to measure the provincial efficiency of industrial pollution control based on the input and output data of industrial pollution control of 29 administrative provinces in China from 2000 to 2017.On this basis,a spatial econometric model was used to explore the influence of environmental regulation intensity on the efficiency of industrial pollution control.In addition,the spatial spillover effect of pollution reduction was thoroughly examined.The results show that:(1)The efficiency of industrial pollution control in China has improved year by year,but the overall efficiency is still low,with the average value increasing from 0.165 in 2000 to 0.309 in 2017.Furthermore,there is significant regional heterogeneity with the highest efficiency level in the east and lowest efficiency level in the west.(2)By increasing the financial and material input,the efficiency of industrial pollution control has increased.However,the increase of human input has not been so helpful.(3)The global Moran’s I index is significantly greater than zero,indicating a strong spatial correlation and agglomeration in the efficiency of industrial pollution control,which is reflected in high-high agglomeration in the eastern region and low-low agglomeration in the western region.(4)Stringent environmental regulation has a positive effect on improving the efficiency of industrial pollution control.It also imposes a positive spatial spillover effect,indicating a strategic interaction and coordination of regional pollution control.In line with this,related proposals have been made to optimize the investment structure for environmental pollution control,establish a flow mechanism for the factor market,and strengthen the environmental responsibility awareness of state-owned enterprises.On this basis,we expect to provide a policy for improving the efficiency of industrial pollution control and promoting regional joint pollution control in China.
基金supported by the National Natural Science Foundation of China(Grant No.12274019)the NSAF Joint Fund(Grant No.U2230402)。
文摘Finding the optimal control is of importance to quantum metrology under a noisy environment.In this paper,we tackle the problem of finding the optimal control to enhance the performance of quantum metrology under an arbitrary non-Markovian bosonic environment.By introducing an equivalent pseudomode model,the non-Markovian dynamic evolution is reduced to a Lindblad master equation,which helps us to calculate the gradient of quantum Fisher information and perform the gradient ascent algorithm to find the optimal control.Our approach is accurate and circumvents the need for the Born-Markovian approximation.As an example,we consider the frequency estimation of a spin with pure dephasing under two types of non-Markovian environments.By maximizing the quantum Fisher information at a fixed evolution time,we obtain the optimal multi-axis control,which results in a notable enhancement in quantum metrology.The advantage of our method lies in its applicability to the arbitrary non-Markovian bosonic environment.
文摘To effectively select risk control schemes in uncertain environments,this paper has proposed an analysis and evaluation method based on the fuzzy comprehensive evaluation method.Firstly,enterprises have adopted the brainstorming method and the Delphi method to identify risks in engineering projects,and organized the identified risks in the form of checklists to facilitate further analysis.Secondly,the fuzzy comprehensive evaluation theory was introduced to determine the comparison matrix of each risk factor and its weight.Furthermore,the top five risk factors in terms of weight ranking were taken as the evaluation factors for the selection of risk control plans.The plans were scored through the weighted scoring method,and the optimal risk control plan was determined based on the score.Finally,the feasibility of the proposed selection technology was verified through A research example of the risk control plan assessment for the construction project of Enterprise A.
基金support by the National Natural Science Foundation of China Grant No.81072313
文摘Objective To investigate the association between autism and prenatal environmental risk factors.Methods A case-control study was conducted among 193 children with autism from the specialeducational schools and 733 typical development controls matched by age and gender by usingquestionnaire in Tianjin from 2007 to 2012. Statistical analysis included quick unbiased efficientstatistical tree (QUEST) and logistic regression in SPSS 20.0.Results There were four predictors by QUEST and the logistic regression analysis, maternal airconditioner use during pregnancy (OR=0.316, 95% CI: 0.215-0.463) was the single first-level node(χ2=50.994, P=0.000); newborn complications (OR=4.277, 95% CI: 2.314-7.908) and paternalconsumption of freshwater fish (OR=0.383, 95% CI: 0.256-0.573) were second-layer predictors(χ2=45.248, P=0.000; χ2=24.212, P=0.000); and maternal depression (OR=4.822, 95% CI: 3.047-7.631)was the single third-level predictor (χ2=23.835, P=0.000). The prediction accuracy of the tree was 89.2%.Conclusion The air conditioner use during pregnancy and paternal freshwater fish diet might bebeneficial for the prevention of autism, while newborn complications and maternal depression might bethe risk factors.
文摘Traditional two-pass weed management strategies need to be compared with new strategies in glyphosate/dicamba-resistant soybean. Weed control, soybean yield, partial profitability and environmental impact (EI) were evaluated in glyphosate/dicamba-resistant soybean using dicamba applied alone or in a tank-mix with dimethenamid-P applied preemergence (PRE). Trials were conducted at three locations during 2014 and 2015. Several PRE herbicides provided excellent control of broadleaf and grass weeds. Dicamba provided > 91% control of broadleaf weeds, and the addition of dimethenamid-P improved grass control. All weed species at the trial locations were controlled > 94% following a postemergence (POST) application of glyphosate. Weed interference reduced soybean seed yield 33% where no herbicide was applied. A single POST application of glyphosate had the lowest EI. Several treatments improved early-season weed control and reduced early-season weed density and biomass compared to glyphosate and had similar EI values. In this study, there was no benefit to yield or partial profit by including a PRE herbicide for weed management;however, the inclusion of multiple modes-of-action in a herbicide program may reduce the selection for herbicide-resistant weeds.