[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the ...[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the reason of dry straight head disease in Chuzhou area, some common control measures were summarized. [Result] The characteristic of main symptoms included incidence of single plant, incidence of cluster, inclusive incidence between clusters. Sporadic normal rice grains existed in diseased spikes under the incidence of grains. The main pathogenic factors of dry straight head disease were concentration of arsenic or lack of elements, belonging to physiological disease, while the effect of other pathogenic factors could not be excluded. Heavy application of organic fertilizer and crop rotation should be conducted, white soil field should be paid more attention about the changes of disease condition with more wet and dry roasting over fields. Application time of micro fertilizer should be chosen properly, while tillering final stage and pollen formation stage must be adjusted to avoid high temperature, irrigation management should also be improved. [Conclusion] The study could provide reference for preventing rice dry straight head disease.展开更多
Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly loca...Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly localized energy can produce large temperature gradients,which will,in turn,lead to compressive and tensile stress during the MAM process and eventually result in residual stress.Being an issue of great concern,residual stress,which can cause distortion,delamination,cracking,etc.,is considered a key mechanical quantity that affects the manufacturing quality and service performance of MAM parts.In this review paper,the ongoing work in the field of residual stress determination and control for MAM is described with a particular emphasis on the experimental measurement/control methods and numerical models.We also provide insight on what still requires to be achieved and the research opportunities and challenges.展开更多
The present paper proposes an automated Laser-Induced Breakdown Spectroscopy （LIBS） analytical test system, which consists of a LIBS measurement and control platform based on a modular design concept, and a LIBS qua...The present paper proposes an automated Laser-Induced Breakdown Spectroscopy （LIBS） analytical test system, which consists of a LIBS measurement and control platform based on a modular design concept, and a LIBS qualitative spectrum analysis software and is developed in C#. The platform provides flexible interfacing and automated control; it is compatible with different manufacturer component models and is constructed in modularized form for easy ex- pandability. During peak identification, a more robust peak identification method with improved stability in peak identification has been achieved by applying additional smoothing on the slope obtained by calculation before peak identification. For the purpose of element identification, an improved main lines analysis method, which detects all elements on the spectral peak to avoid omission of certain elements without strong spectral lines, is applied to element identification in the tested LIBS samples. This method also increases the identification speed. In this paper, actual applications have been carried out. According to tests, the analytical test system is compatible with components of various models made by different manufacturers. It can automatically control components to get experimental data and conduct filtering, peak identification and qualitative analysis, etc. on spectral data.展开更多
The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growt...The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growth and propagation of hydrophyta, therefore the key to the prevention and control of eutrophication in lakes lies in the control of the contents of the two elements in the water. Artificial fishing of algae can reduce the concentrations of trophic substances such as nitrogen and phosphorus in the water bodies, and biological measures may decrease the contents of these trophic substances in the bottom sediments and the water bodies, thereby playing an active role in modifying the eutrophication of the lake.展开更多
To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is ...To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.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
Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis i...Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis infection control measures in health care facilities. To evaluate the effectiveness of infection control measures, such study was planned. Questionnaires were administered to all doctors, healthcare workers and servants working in outdoor and indoor department of tuberculosis at tertiary care hospital to assess the knowledge, attitudes and practices on prevention and control of Tuberculosis infection. A scoring system was devised to grade them. One-time audit was also done in outpatient and inpatient department. The analysis showed scoring of poor for doctors, good for nurses and poor forward aids. There is a need to develop strategies for training of health care workers on regular basis in order to reduce the incidence of nosocomial infections. Audit result shows a good level of environmental control measures. Better knowledge, attitude and practices are helpful for the prevention and control of tuberculosis. Also environmental control measures are helpful to prevent infection.展开更多
Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in ...Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and noise.Based on the aerodynamic validation model CAE-AVM,Chinese Aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise conditions.Various structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are developed.The deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on load.The results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing capacity.Our study can provide some insights into the application of variable camber wing technology for civil aircraft.展开更多
Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example t...Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.展开更多
In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and cont...In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and control system was developed. Based on the characteristics of each LIBS component, the following development steps have been performed:( 1) a summary of characteristic parameters of the component are established;( 2) the integration mechanism of multiple electrical interfaces is designed;( 3) the component control instruction library is developed. The experimental results indicate that the measurement and control system is compatible with most LIBS parts in the market.Spectrometer and laser can be compatible with at least three different types of parts. In addition,a multilayer iterative testing process is designed to improve the efficiency of optimization process of LIBS parameters. The experimental results have shown that the automatic optimization of the delay time compared to the manual testing provides significant gain in testing efficiency. The range of delay time in the experiments is 1. 28 to 10. 28 μs and the step value is 1,0. 5,0. 2 and 0. 1 μs. The gain in testing efficiency has been found to be increased by 73. 76%,75. 93%,78. 81% and 80. 42%,respectively.展开更多
This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stoppi...This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stopping on the quay. Using a case study methodology and focusing on the Italian context, this exploratory study, through a qualitative approach, interviewed two main cruise terminal concessionaires and indirectly observed events planned by cruise companies in sea ports selected for outlining the role of control systems, coordination, and knowledge sharing between the players in cruise events decision-making processes. The first results show that the cruise event management processes on ship berthing and on terminal are separated. The cruise companies don＇t involve terminal concessionaires in the event organization considering them only service suppliers Also, the concessionaires conceive the events planned in the cruise infrastructures as a business unit to optimize the space use, without any forms of coordination or control with cruise companies. Knowledge sharing, coordination, and control among the two players could support the planning, and management of ＂new cruise events＂ in which the visitors may be led from the infrastructure to the ships stopped on the quay. This study offers a set of key performance indicators to support the management, control, and coordination of each inter-organizational relationship identified. Managerial implications and suggestions for improving cruise events management have been provided.展开更多
Bovine viral diarrhea disease is an important disease in the world, which causes great economic loss and leads to serious clinical symptoms such as drop in milk and meat production, reproductive failure, growth retard...Bovine viral diarrhea disease is an important disease in the world, which causes great economic loss and leads to serious clinical symptoms such as drop in milk and meat production, reproductive failure, growth retardation, and secondary infection increasing the mortality rate. The developed countries have made a series of measures in preventing the disease and made a great purpose. This paper summarizes those methods in order to make a reference for the control of the disease in China.展开更多
Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and...Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda.展开更多
Ceracris kiangsu Tsai is one of the most widely distributed forest pest.C.kiangsu has migrated from Laos to China this year,with many migration peaks and large population numbers.The main sources of C.kiangsu were fro...Ceracris kiangsu Tsai is one of the most widely distributed forest pest.C.kiangsu has migrated from Laos to China this year,with many migration peaks and large population numbers.The main sources of C.kiangsu were from abroad and a small number of native insect sources exist.Most of the immigration sources were from Laos,and a small part originated from Vietnam.The frontier region of Yunnan Province is suitable for the growth of C.kiangsu.It is speculated that the migration frequency of the C.kiangsu from abroad may increase in recent years.In this paper,the typical morphological characteristics,life history,biological characteristics and prevention and control measures of C.kiangsu were summarized.Based on the characteristics of C.kiangsu,and combining actual sugarcane production condition in Yunnan sugarcane areas,we put forward prevention and control strategies and measures.It is suggested that Yunnan Sugarcane areas should pay close attention to the occurrence of C.kiangsu in neighboring countries,monitor the C.kiangsu population dynamics and update pest forecast information in time,and detect and control C.kiangsu in the early period,in order to effectively prevent C.kiangsu and ensure the safety of sugarcane production.展开更多
Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivati...Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.展开更多
With the development of the times, the status of power resources in China's social and economic development is getting higher and higher. To ensure the safe operation of power grid has become one of the important ...With the development of the times, the status of power resources in China's social and economic development is getting higher and higher. To ensure the safe operation of power grid has become one of the important issues in the operation and management of power enterprises. In the process of operation and management of power enterprises, the application of power automation system can provide security for power grid operation and effectively avoid large-scale blackout. Therefore, the intelligent protection and measurement and control equipment of power automation system needs further design and development. Accurate real-time monitoring of power system operation status information and intelligent automatic decision-making control are the primary tasks for the intelligent promotion of power system in the future. With the rapid development of economy, the power consumption increases rapidly, and the structure of power system becomes more complex. The high fluctuation of power consumption in the peak period brings great pressure to the power grid. In the power system, the operation parameters become huge, and the parameters are interrelated and highly coupled. On the one hand, the highly complex power equipment needs the intensive monitoring of professional and technical personnel, on the other hand, the monitoring of power system has the problem of high security risk. Therefore, it is necessary to develop a set of intelligent power system state detection system, which can not only realize the accurate perception and intelligent decision-making of power system, but also realize the control and execution of the system.展开更多
Crop diseases and insect pests are the key factors affecting stable and increased grain production, and prevention and control of crop diseases and insect pests are the key measures for disaster reduction and bumper h...Crop diseases and insect pests are the key factors affecting stable and increased grain production, and prevention and control of crop diseases and insect pests are the key measures for disaster reduction and bumper harvest. For farmers, the most important concern is also the crop yield. They want to improve the yield and do a good job in pest control. In order to organize the prevention and control of plant diseases and insect pests, minimize the damage and loss, improve the agricultural output and increase the income of farmers. This paper summarizes the common diseases and insect pests of crops in Tibet and their control methods.展开更多
In the information age, power resources have become the necessary energy to maintain social development, and people's dependence on the power system has gradually increased. As a vital node facility of the power s...In the information age, power resources have become the necessary energy to maintain social development, and people's dependence on the power system has gradually increased. As a vital node facility of the power system, 110kV substation needs to adjust the management strategy in combination with the daily operation and maintenance of the substation. However, in the current substation management, there is a general concern about management risks inadequate consideration of technical risks and external operation and maintenance risks has seriously affected the stability of power system and power quality. Targeted preventive measures should be taken to improve the operation and maintenance capacity of 110kV substation.展开更多
In the context of rising global energy demand and increasing awareness of environmental protection,photovoltaic power generation,as a clean and renewable form of energy,has become increasingly important and has receiv...In the context of rising global energy demand and increasing awareness of environmental protection,photovoltaic power generation,as a clean and renewable form of energy,has become increasingly important and has received widespread attention and application worldwide.However,during the construction and operation of mountain photovoltaic power generation projects,water and soil erosion has become a major challenge,which not only restricts the sustainable development process of the project,but also has a significant negative impact on the local ecological environment.This article deeply analyzes the multiple causes,extensive impacts and effective prevention and control strategies of water and soil erosion in mountain photovoltaic power generation projects.The results show that rainfall intensity,terrain slope,soil type and vegetation coverage are the four key factors leading to soil erosion.Soil erosion not only causes a sharp decline in soil fertility,but also aggravates the problem of sediment deposition in rivers and reservoirs,and poses a direct threat to the stability and operating efficiency of photovoltaic equipment.In order to deal with the above problems,this paper innovatively puts forward a series of soil and water conservation technologies,covering multiple dimensions such as engineering measures,plant measures,farming measures and temporary measures,and deeply discusses the application models and management strategies of these measures in key stages such as planning and design,construction,operation and maintenance.Through specific case analysis,the successful practical experience of soil and water conservation is refined and summarized,and the key role of community cooperation,technical support and modern monitoring technology in preventing and controlling soil and water erosion is further emphasized.This article aims to achieve a win-win situation of ecological environment protection and energy development and utilization through scientific planning and effective governance,and contribute to the construction of a green,low-carbon,and sustainable energy system.展开更多
Pseudorabies(PR),also called Aujeszky's disease,is a highly infectious disease caused by pseudorabies virus(PRV).Without specific host tropism,PRV can infect a wide variety of mammals,including pig,sheep,cattle,et...Pseudorabies(PR),also called Aujeszky's disease,is a highly infectious disease caused by pseudorabies virus(PRV).Without specific host tropism,PRV can infect a wide variety of mammals,including pig,sheep,cattle,etc.,thereby causing severe clinical symptoms and acute death.PRV was firstly reported in China in 1950s,while outbreaks of emerging PRV variants have been documented in partial regions since 2011,leading to significant economic losses in swine industry.Although scientists have been devoting to the design of diagnostic approaches and the development of vaccines during the past years,PR remains a vital infectious disease widely prevalent in Chinese pig industry.Especially,its potential threat to human health has also attracted the worldwide attention.In this review,we will provide a summary of current understanding of PRV in China,mainly focusing on PRV history,the existing diagnosis methods,PRV prevalence in pig population and other susceptible mammals,molecular characteristics,and the available vaccines against its infection.Additionally,promising agents including traditional Chinese herbal medicines and novel inhibitors that may be employed to treat this viral infection,are also discussed.展开更多
文摘[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the reason of dry straight head disease in Chuzhou area, some common control measures were summarized. [Result] The characteristic of main symptoms included incidence of single plant, incidence of cluster, inclusive incidence between clusters. Sporadic normal rice grains existed in diseased spikes under the incidence of grains. The main pathogenic factors of dry straight head disease were concentration of arsenic or lack of elements, belonging to physiological disease, while the effect of other pathogenic factors could not be excluded. Heavy application of organic fertilizer and crop rotation should be conducted, white soil field should be paid more attention about the changes of disease condition with more wet and dry roasting over fields. Application time of micro fertilizer should be chosen properly, while tillering final stage and pollen formation stage must be adjusted to avoid high temperature, irrigation management should also be improved. [Conclusion] The study could provide reference for preventing rice dry straight head disease.
基金financially supported by the National Natural Science Foundation of China(12032013,12272131)the Provincial Natural Science Foundation of Hunan(2022JJ40029)the Scientific Research Foundation of Hunan Provincial Education Department(21C0087)。
文摘Metal additive manufacturing(MAM)is an emerging and disruptive technology that builds three-dimensional(3D)components by adding layer-upon-layer of metallic materials.The complex cyclic thermal history and highly localized energy can produce large temperature gradients,which will,in turn,lead to compressive and tensile stress during the MAM process and eventually result in residual stress.Being an issue of great concern,residual stress,which can cause distortion,delamination,cracking,etc.,is considered a key mechanical quantity that affects the manufacturing quality and service performance of MAM parts.In this review paper,the ongoing work in the field of residual stress determination and control for MAM is described with a particular emphasis on the experimental measurement/control methods and numerical models.We also provide insight on what still requires to be achieved and the research opportunities and challenges.
基金supported by the National Major Scientific Instruments and Equipment Development Special Funds of China(No.2011YQ030113)
文摘The present paper proposes an automated Laser-Induced Breakdown Spectroscopy （LIBS） analytical test system, which consists of a LIBS measurement and control platform based on a modular design concept, and a LIBS qualitative spectrum analysis software and is developed in C#. The platform provides flexible interfacing and automated control; it is compatible with different manufacturer component models and is constructed in modularized form for easy ex- pandability. During peak identification, a more robust peak identification method with improved stability in peak identification has been achieved by applying additional smoothing on the slope obtained by calculation before peak identification. For the purpose of element identification, an improved main lines analysis method, which detects all elements on the spectral peak to avoid omission of certain elements without strong spectral lines, is applied to element identification in the tested LIBS samples. This method also increases the identification speed. In this paper, actual applications have been carried out. According to tests, the analytical test system is compatible with components of various models made by different manufacturers. It can automatically control components to get experimental data and conduct filtering, peak identification and qualitative analysis, etc. on spectral data.
文摘The Hydrobios in Dongping Lake, Shandong Province, mainly includes phytoplankton, zooplankton, benthic animals, fishes and hydrophytic vascular plants. Nitrogen and phosphorus are the restrictive factors for the growth and propagation of hydrophyta, therefore the key to the prevention and control of eutrophication in lakes lies in the control of the contents of the two elements in the water. Artificial fishing of algae can reduce the concentrations of trophic substances such as nitrogen and phosphorus in the water bodies, and biological measures may decrease the contents of these trophic substances in the bottom sediments and the water bodies, thereby playing an active role in modifying the eutrophication of the lake.
文摘To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.
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.
文摘Tuberculosis is one of the most important infectious diseases in our country. Also nosocomial infection by tuberculosis can occur, which can be prevented by implementing simple, effective and affordable tuberculosis infection control measures in health care facilities. To evaluate the effectiveness of infection control measures, such study was planned. Questionnaires were administered to all doctors, healthcare workers and servants working in outdoor and indoor department of tuberculosis at tertiary care hospital to assess the knowledge, attitudes and practices on prevention and control of Tuberculosis infection. A scoring system was devised to grade them. One-time audit was also done in outpatient and inpatient department. The analysis showed scoring of poor for doctors, good for nurses and poor forward aids. There is a need to develop strategies for training of health care workers on regular basis in order to reduce the incidence of nosocomial infections. Audit result shows a good level of environmental control measures. Better knowledge, attitude and practices are helpful for the prevention and control of tuberculosis. Also environmental control measures are helpful to prevent infection.
基金supported by the National Research Project“Variable Camber Wing Technology(VCAN)”,China。
文摘Variable camber wing technology is one of the important development trends of green aviation at present.Through smooth,seamless,continuous and adaptive change of wing camber,the aerodynamic performance is improved in achieving increase in lift and reduction in resistance and noise.Based on the aerodynamic validation model CAE-AVM,Chinese Aeronautical Establishment(CAE)has carried out the design and validation of a variable camber wing,proposed an aerodynamic deformation matrix for the leading and trailing edges of aircraft wings in takeoff,landing and cruise conditions.Various structures and driving schemes are compared,and several key technology problems of leading and trailing edge deformation are solved.A full-size leading edge wind tunnel test piece with a span of 2.7 m and a trailing edge ground function test piece are developed.The deformation and shape maintenance capabilities of the leading edge is verified under real wind load conditions,and the load bearing and deformation capabilities of the trailing edge is verified under simulated follow-on load.The results indicate that the leading and trailing edges of the variable camber wing can achieve the required deformation angle and have a certain load-bearing capacity.Our study can provide some insights into the application of variable camber wing technology for civil aircraft.
文摘Deep foundation pit excavation is a basic and key step involved in modern building construction.In order to ensure the construction quality and safety of deep foundation pits,this paper takes a project as an example to analyze deep foundation pit excavation technology,including the nature of this construction project,the main technical measures in the construction of deep foundation pit,and the analysis of the safety risk prevention and control measures.The purpose of this analysis is to provide scientific reference for the construction quality and safety of deep foundation pits.
基金National M ajor Scientific Instruments and Equipment Development Special Funds,China(No.2011YQ030113)
文摘In order to improve the compatibility of laser-induced breakdown spectroscopy( LIBS) instrument for different types of parts and optimize the analysis and testing processes,a modularized automatic measurement and control system was developed. Based on the characteristics of each LIBS component, the following development steps have been performed:( 1) a summary of characteristic parameters of the component are established;( 2) the integration mechanism of multiple electrical interfaces is designed;( 3) the component control instruction library is developed. The experimental results indicate that the measurement and control system is compatible with most LIBS parts in the market.Spectrometer and laser can be compatible with at least three different types of parts. In addition,a multilayer iterative testing process is designed to improve the efficiency of optimization process of LIBS parameters. The experimental results have shown that the automatic optimization of the delay time compared to the manual testing provides significant gain in testing efficiency. The range of delay time in the experiments is 1. 28 to 10. 28 μs and the step value is 1,0. 5,0. 2 and 0. 1 μs. The gain in testing efficiency has been found to be increased by 73. 76%,75. 93%,78. 81% and 80. 42%,respectively.
文摘This paper investigates the control systems and coordination mechanisms applied in the relationships between cruise line companies and terminal concessionaires in the cruise events management when the ships are stopping on the quay. Using a case study methodology and focusing on the Italian context, this exploratory study, through a qualitative approach, interviewed two main cruise terminal concessionaires and indirectly observed events planned by cruise companies in sea ports selected for outlining the role of control systems, coordination, and knowledge sharing between the players in cruise events decision-making processes. The first results show that the cruise event management processes on ship berthing and on terminal are separated. The cruise companies don＇t involve terminal concessionaires in the event organization considering them only service suppliers Also, the concessionaires conceive the events planned in the cruise infrastructures as a business unit to optimize the space use, without any forms of coordination or control with cruise companies. Knowledge sharing, coordination, and control among the two players could support the planning, and management of ＂new cruise events＂ in which the visitors may be led from the infrastructure to the ships stopped on the quay. This study offers a set of key performance indicators to support the management, control, and coordination of each inter-organizational relationship identified. Managerial implications and suggestions for improving cruise events management have been provided.
基金funded by the National Special Research Fund for Public Welfare (Agriculture) of China (200803018)National Key Technology R&D Program (2009BADB4B02)
文摘Bovine viral diarrhea disease is an important disease in the world, which causes great economic loss and leads to serious clinical symptoms such as drop in milk and meat production, reproductive failure, growth retardation, and secondary infection increasing the mortality rate. The developed countries have made a series of measures in preventing the disease and made a great purpose. This paper summarizes those methods in order to make a reference for the control of the disease in China.
文摘Based on practical work experience,this paper analyzed the occurrence characteristics and control measures of Spodoptera frugiperda in maize.The measures including forecasting and early warning,regional prevention and control,agricultural prevention and control,physical prevention and control,chemical prevention and control,and biological prevention and control can effectively control the damage of S.frugiperda and guarantee the safety of food production.The results will provide some reference for the prevention and control of S.frugiperda.
基金Sugar Crop Research System(CARS-170303)the Yunling Industry and Technology Leading Talent Training Program"Prevention and Control of Sugarcane Pests"(2018LJRC56)the Yunnan Province Agriculture Research System(YNGZTX-4-92)。
文摘Ceracris kiangsu Tsai is one of the most widely distributed forest pest.C.kiangsu has migrated from Laos to China this year,with many migration peaks and large population numbers.The main sources of C.kiangsu were from abroad and a small number of native insect sources exist.Most of the immigration sources were from Laos,and a small part originated from Vietnam.The frontier region of Yunnan Province is suitable for the growth of C.kiangsu.It is speculated that the migration frequency of the C.kiangsu from abroad may increase in recent years.In this paper,the typical morphological characteristics,life history,biological characteristics and prevention and control measures of C.kiangsu were summarized.Based on the characteristics of C.kiangsu,and combining actual sugarcane production condition in Yunnan sugarcane areas,we put forward prevention and control strategies and measures.It is suggested that Yunnan Sugarcane areas should pay close attention to the occurrence of C.kiangsu in neighboring countries,monitor the C.kiangsu population dynamics and update pest forecast information in time,and detect and control C.kiangsu in the early period,in order to effectively prevent C.kiangsu and ensure the safety of sugarcane production.
基金the Genetic Breeding Post Construction Project of Rice Innovation Team for Modern Agricultural Industrial Technology System in Shandong Province of China(SDAIT-17-02).
文摘Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD.
文摘With the development of the times, the status of power resources in China's social and economic development is getting higher and higher. To ensure the safe operation of power grid has become one of the important issues in the operation and management of power enterprises. In the process of operation and management of power enterprises, the application of power automation system can provide security for power grid operation and effectively avoid large-scale blackout. Therefore, the intelligent protection and measurement and control equipment of power automation system needs further design and development. Accurate real-time monitoring of power system operation status information and intelligent automatic decision-making control are the primary tasks for the intelligent promotion of power system in the future. With the rapid development of economy, the power consumption increases rapidly, and the structure of power system becomes more complex. The high fluctuation of power consumption in the peak period brings great pressure to the power grid. In the power system, the operation parameters become huge, and the parameters are interrelated and highly coupled. On the one hand, the highly complex power equipment needs the intensive monitoring of professional and technical personnel, on the other hand, the monitoring of power system has the problem of high security risk. Therefore, it is necessary to develop a set of intelligent power system state detection system, which can not only realize the accurate perception and intelligent decision-making of power system, but also realize the control and execution of the system.
文摘Crop diseases and insect pests are the key factors affecting stable and increased grain production, and prevention and control of crop diseases and insect pests are the key measures for disaster reduction and bumper harvest. For farmers, the most important concern is also the crop yield. They want to improve the yield and do a good job in pest control. In order to organize the prevention and control of plant diseases and insect pests, minimize the damage and loss, improve the agricultural output and increase the income of farmers. This paper summarizes the common diseases and insect pests of crops in Tibet and their control methods.
文摘In the information age, power resources have become the necessary energy to maintain social development, and people's dependence on the power system has gradually increased. As a vital node facility of the power system, 110kV substation needs to adjust the management strategy in combination with the daily operation and maintenance of the substation. However, in the current substation management, there is a general concern about management risks inadequate consideration of technical risks and external operation and maintenance risks has seriously affected the stability of power system and power quality. Targeted preventive measures should be taken to improve the operation and maintenance capacity of 110kV substation.
文摘In the context of rising global energy demand and increasing awareness of environmental protection,photovoltaic power generation,as a clean and renewable form of energy,has become increasingly important and has received widespread attention and application worldwide.However,during the construction and operation of mountain photovoltaic power generation projects,water and soil erosion has become a major challenge,which not only restricts the sustainable development process of the project,but also has a significant negative impact on the local ecological environment.This article deeply analyzes the multiple causes,extensive impacts and effective prevention and control strategies of water and soil erosion in mountain photovoltaic power generation projects.The results show that rainfall intensity,terrain slope,soil type and vegetation coverage are the four key factors leading to soil erosion.Soil erosion not only causes a sharp decline in soil fertility,but also aggravates the problem of sediment deposition in rivers and reservoirs,and poses a direct threat to the stability and operating efficiency of photovoltaic equipment.In order to deal with the above problems,this paper innovatively puts forward a series of soil and water conservation technologies,covering multiple dimensions such as engineering measures,plant measures,farming measures and temporary measures,and deeply discusses the application models and management strategies of these measures in key stages such as planning and design,construction,operation and maintenance.Through specific case analysis,the successful practical experience of soil and water conservation is refined and summarized,and the key role of community cooperation,technical support and modern monitoring technology in preventing and controlling soil and water erosion is further emphasized.This article aims to achieve a win-win situation of ecological environment protection and energy development and utilization through scientific planning and effective governance,and contribute to the construction of a green,low-carbon,and sustainable energy system.
基金This work was supported by the General Program of National Natural Science Foundation of China(Grants No.31571432/31802252)the Hunan Provincial Natural Science Foundation of China(Grant No.2015JC3097/2020JJ4041)the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20200659).
文摘Pseudorabies(PR),also called Aujeszky's disease,is a highly infectious disease caused by pseudorabies virus(PRV).Without specific host tropism,PRV can infect a wide variety of mammals,including pig,sheep,cattle,etc.,thereby causing severe clinical symptoms and acute death.PRV was firstly reported in China in 1950s,while outbreaks of emerging PRV variants have been documented in partial regions since 2011,leading to significant economic losses in swine industry.Although scientists have been devoting to the design of diagnostic approaches and the development of vaccines during the past years,PR remains a vital infectious disease widely prevalent in Chinese pig industry.Especially,its potential threat to human health has also attracted the worldwide attention.In this review,we will provide a summary of current understanding of PRV in China,mainly focusing on PRV history,the existing diagnosis methods,PRV prevalence in pig population and other susceptible mammals,molecular characteristics,and the available vaccines against its infection.Additionally,promising agents including traditional Chinese herbal medicines and novel inhibitors that may be employed to treat this viral infection,are also discussed.
