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Impact of Migrant Populations on Tuberculosis Rates in Saudi Arabia: Assessing How Migration Patterns Affect TB Incidence and Control Measures: A Narrative Review
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作者 Neda Ali Al Bati 《Journal of Tuberculosis Research》 2024年第3期165-181,共17页
This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global s... This research focuses on the effects of migration on the TB infection rate and its prevention in Saudi Arabia, which has a large number of expatriates from TB-affected countries. Despite, based on the current global statistics of TB occurrence, it is evident that the national incidence of TB has reduced from 10.55 per 100,000 in 2015 to 8.36 per 100,000 in 2019;despite this, there are still some difficulties because migrants bring new strains of Mycobacterium tuberculosis. Hindrances, including language barriers and perceived immigration status, hinder patients from seeking medical attention or doctors from diagnosing diseases. Each patient and each cultural group need special attention to public health, enhancing living circumstances, and health care support. Community participation, inclusion of TB control programs into functional healthcare facilities, and the functioning of TB programs need to be stressed to address TB issues. Considering the focus on social, economic, and cultural approaches, the country can make severe advancements in TB control and population protection. This holistic analysis is critical for a long-term effective strategy to combat TB in the Kingdom. 展开更多
关键词 Kingdom Saudi Arabia (KSA) Tuberculosis (TB) Prevalence MIGRANTS control Measures
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PRECISE INTEGRATION METHOD FOR LQG OPTIMAL MEASUREMENT FEEDBACK CONTROL PROBLEM 被引量:1
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作者 钟万勰 蔡志勤 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第12期1417-1422,共6页
By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separ... By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separates, into an optimal state-feedback control problem and an optimal state estimation problem. That is the off-line solution of two sets of Riccati differential equations and the on-line integration solution of the state vector from a set of time-variant differential equations. The present algorithms are not only appropriate to solve the two-point boundary-value problem and the corresponding Riccati differential equation, but also can be used to solve the estimated state from the time-variant differential equations. The high precision of precise integration is of advantage for the control and estimation. Numerical examples demonstrate the high precision and effectiveness of the algorithm. 展开更多
关键词 precise integration LQG measurement feedback control Riccati differential equation time-variant differential equation
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Study on DeviceNet communication mechanism and its application in protection measurement and control system 被引量:1
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作者 佟为明 Li Zhongwei +1 位作者 Sun Fanjin Cheng Shukang 《High Technology Letters》 EI CAS 2007年第1期1-5,共5页
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
关键词 communication mechanism protection measurement and control system FIELDBUS DEVICENET
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A review on stress determination and control in metal-based additive manufacturing 被引量:3
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作者 Haoyang Luo Xing Sun +2 位作者 Le Xu Wei He Xiaoyu Liang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第1期14-25,共12页
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
关键词 Metal additive manufacturing Residual stress measurement and control methods Numerical models
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Design of a Modularized Automatic Measurement and Control System for LaserInduced Breakdown Spectrometer
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作者 丁宇 田地 +2 位作者 陈飞鹏 乔淑君 杨光 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期406-410,共5页
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
关键词 automatic control technique laser-induced breakdown spectroscopy(LIBS) measurement and control system(MCS) COMPONENT
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The 3rd Asia-Pacfic Conference on Control and Measurement(APCCM’98)Will Be Held
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作者 Chunru 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第2期135-135,共1页
The 3rd Asia-Pacfic Conference on Control and Measurement Sponsored by IEEE Shanghai Subsec-tion,Jiangsu Society of Aeronautics and Astronautics,Nanjing University of Aeronautics and Astronau-tics and the City Univers... The 3rd Asia-Pacfic Conference on Control and Measurement Sponsored by IEEE Shanghai Subsec-tion,Jiangsu Society of Aeronautics and Astronautics,Nanjing University of Aeronautics and Astronau-tics and the City University of Hong Kong will be held on August31 to September4,1998 in Dun-huang,China.APCCM Conference is the best chance for scholars,experts and engineers on control andmeasurement fields from the world to propose their academic insights,exchange their academic achieve-ments and enhance international cooperations.The purpose of of the APCCM’98 is to bring togetherscholars and experts engaging in control and measurement research to highlight new issues and contribu-tions of information technology for advances in industrial engineering.The topics of this conference arepresented as follows:control engineering,ideniification,modeling and system theory,specification andimplementation languages,controller synthesis,computer-aided design and simulation,algorithm anddeductive verification,fiber 展开更多
关键词 ASIA The 3rd Asia-Pacfic Conference on control and measurement Will Be Held In APCCM
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Construction Technology and Safety Risk Control Measures of Deep Foundation Pit Excavation 被引量:1
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作者 Mingmin Jiang 《Journal of World Architecture》 2023年第2期24-29,共6页
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
关键词 Construction engineering Deep foundation pit excavation Construction technology Risk prevention and control measures
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Occurrence Characteristics and Prevention and Control Measures of Spodoptera frugiperda in Maize
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作者 Liping DONG Chunming LIU 《Plant Diseases and Pests》 CAS 2023年第3期8-9,共2页
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
关键词 Spodoptera frugiperda Occurrence characteristics Prevention and control measures MAIZE
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Control of Bursaphelenchus xylophilus in the State-owned Sishibacao Forest Farm of Yunyang County,China
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作者 Chunhua TANG Hejun ZHANG 《Agricultural Biotechnology》 CAS 2023年第2期127-132,共6页
In view of the fact that pine wood nematode disease is the most dominant disease in Pinus massoniana forests,which has the characteristics of strong infectivity,fast transmission speed,and great difficulty in preventi... In view of the fact that pine wood nematode disease is the most dominant disease in Pinus massoniana forests,which has the characteristics of strong infectivity,fast transmission speed,and great difficulty in prevention and control,a brief description was made to the occurrence status of pine wood nematode disease and difficulties faced with its control in the State-owned Sishibacao Forest Farm of Yunyang County,China,followed by the analysis on the prevention and control measures from aspects of strict control,epidemic situation monitoring,joint prevention and control,and clearance of infected trees,as well as the existing problems of pine wood nematode disease.Finally,reasonable suggestions including strengthening the construction of talent team were put forward,aiming to provide a beneficial reference for the scientific,efficient,and reasonable control of pine wood nematode disease in Pinus massoniana Lamb.forests of Yunyang State-owned Sishibacao Forest Farm. 展开更多
关键词 Pine wood nematode disease Occurrence status control measures
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Cause of over Water Quality Standard and Control Measures of State-controlled Sections in Northern Water-deficient Area of Jiangsu 被引量:5
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作者 胡永定 韩宝平 +1 位作者 钱新 袁兴程 《Meteorological and Environmental Research》 CAS 2010年第2期91-94,99,共5页
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r... Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology. 展开更多
关键词 State-controlled sections Cause analysis control measures Water-deficient area China
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Analysis on Current Situation,Formation Causes and Control Countermeasures of Acid Rain Pollution in China 被引量:3
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作者 万玉山 王皖蒙 《Meteorological and Environmental Research》 CAS 2010年第10期92-95,共4页
Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,s... Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China. 展开更多
关键词 Acid rain pollution Causes of pollution Hazards control measures China
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Identification and Control of Persimmon anthracnose 被引量:1
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作者 杜社妮 白岗栓 +1 位作者 张树军 张蕊 《Plant Diseases and Pests》 CAS 2010年第1期40-42,共3页
[ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon ... [ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon anthracnose were stated simply and the methods for con- trolling the disease were summed up. [ Result] The pathogen of Persimmon anthracnose was Gloeospor/um kaki Hod, belonging to Deuteromycotina. Germination and invasion of the conidia, sporulation and growth of mycelium all required high temperature, with the optimum temperature of 25 ℃ and the lethal temperature of 50 ℃ (10 min). The occurrence strength of Persimmon anthracnose related with the factors including host, environment, culture circumstances, mainly doing harm to the fruits and branches. The occurrence of the disease could be controlled by such agricultur- al measures as cleaning the orchard, using the resistant varieties and planting the disease-free seedlings, adopting the balanced fertilization, improving the irrigation and drainage systems, conducting the dense planting and thin branches, building garden using the seedling that grafting on planted stock and raising the grafted parts of the stock. When the incidence was heavy, it needed to spray the fungicides or protective agent for the control of the Persimmon anthracnose. The fungicides should be mainly sprayed on the lesion of shoot, fruit surface and branches. [ Conclusion] The study provided the reference for the control of the Persimmon anthracnose. 展开更多
关键词 Persimmon anthracnose Damage symptoms Occurrence law controlling measure
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Development Characteristics and Control Measures for Semiothisa cineraria Bremer & Grey 被引量:1
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作者 唐浩 李军民 +2 位作者 吴家全 高华清 张松光 《Agricultural Science & Technology》 CAS 2014年第6期933-936,共4页
The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and ac... The development characteristics of Semiothisa cinerearia Bremer & Grey was summarized, and we also put forward the control measures of well completing insect surveys to provide scientific basis for the control and actively carrying out comprehensive management to control the pests damage in the economic permissible level. 展开更多
关键词 Semiothisa cinerearia Bremer Grey Development characteristics control measures
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Analysis on Aquatic Environment of an Artificial Lake and Control Measures to Its Pollution 被引量:1
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作者 杨银科 王文科 +1 位作者 邓红章 孙浩 《Agricultural Science & Technology》 CAS 2012年第8期1749-1753,共5页
[Objective] This study aimed to find out effective measures to solve land- scape water eutrophication. [Method] Based on an overview of the urban landscape water characteristics and pollution control situation, taking... [Objective] This study aimed to find out effective measures to solve land- scape water eutrophication. [Method] Based on an overview of the urban landscape water characteristics and pollution control situation, taking an example of the artificial lakes in a campus in Xi'an, we comparatively analyzed the present pollution situation of Xiuyuan Lake and Mingyuan Lake, and provided controlling measures against eutrophication pollution, as well as restoration measures. [Result] All the indicators (TN, TP, Chl-a, NH3-N, CODMn) of the landscape water quality in both Xiuyuan Lake and Mingyuan Lake went severely beyond the Grade IV standards, presenting a state of heavy eutrophication. Nitrogen, phosphorus and other nutrient salts carried by atmospheric precipitation and its runoff, as well as domestic garbage generated by human activities were primary exogenous pollutants of the artificial lakes. And the release of sediment pollutants was endogenous substances causing deterioration of water quality. [Conclusion] This paper presents some measures to control the pollution of artificial lakes, and provides scientific references for the construction, operation and management of artificial lakes, as well as maintenance of aquatic environment. 展开更多
关键词 Urban landscape water EUTROPHICATION control measures
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High-precision alkali-atom density measurement and control methods using light absorption for dual-beam SERF magnetometers
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作者 刘子傲 陆吉玺 +4 位作者 胡朝晖 李晓昱 闫一凡 詹迪 李建利 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第5期41-46,共6页
The alkali-atom density measurement method based on light absorption is highly suitable for a spin-exchange relaxationfree(SERF)atomic magnetometer because of its high-precision measurement and complete nonmagnetic in... The alkali-atom density measurement method based on light absorption is highly suitable for a spin-exchange relaxationfree(SERF)atomic magnetometer because of its high-precision measurement and complete nonmagnetic interference.In this study,the optical rotation angle detection system based on polarization balance detection is utilized to realize the alkali-atom density real-time measurement without affecting magnetic field measurement.We discovered that there exists an optimal frequency detuning of the probe light,which offers the highest sensitivity in alkali-atom density measurement and the lowest susceptibility to temperature fluctuations in terms of the scale factor.In contrast to conventional light absorption measurements based on pump light,this method demonstrated a threefold improvement in alkali-atom density measurement sensitivity while remaining immune to ambient magnetic fields and incident light intensity fluctuations.Furthermore,we utilized this method to achieve closed-loop temperature control with an accuracy of 0.04℃. 展开更多
关键词 light absorption temperature measurement and control dual-beam SERF magnetometer
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Biological Characteristics of Sugarcane Rust in Beihai and Its Control Methods
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作者 韦金菊 邓展云 +3 位作者 黄伟华 潘雪红 王伯辉 刘晓静 《Plant Diseases and Pests》 CAS 2010年第4期16-19,共4页
The sugarcane rust was the main disease causing damage on sugarcane leaves. The biological characteristics of the sugarcane rust pathogens found in Beihai were studied. The research results showed that the germination... The sugarcane rust was the main disease causing damage on sugarcane leaves. The biological characteristics of the sugarcane rust pathogens found in Beihai were studied. The research results showed that the germination of uredospores would be promoted under the dark condition or with the glucose concentration of 1.5%. The suitable temperature range for the germination of uredospore was 20 -25 ℃, 25 ℃3 was the optimum temperature. The range of relative humidity (RH) for the germination of uredospore was over 80%, the optimum relative humidity for the germination of uredospore was 100% +water drops with the germination rate of 28.3%. Urediospore could germinate in the pH value range of 4.1 - 11.1, the most suitable pH value was 7.0. At routine conditions, the longest survival period of uredospore was 120 days. Selection of resistant varieties and cultivation management was the key of control measures. 展开更多
关键词 Sugarcane rust Biological charactedstics control measures
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Usage of Pesticides and Control Measures in Qujing City
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作者 赵红艳 杨鑫 +1 位作者 崔丹 何焕云 《Agricultural Science & Technology》 CAS 2013年第8期1156-1159,共4页
[Objective] The aim was to investigate pesticide use in Qujing city and explore the control measures.[Method] Surveys were made on pesticide use by farmers in five vegetable bases in Qujing city by questionnaires to s... [Objective] The aim was to investigate pesticide use in Qujing city and explore the control measures.[Method] Surveys were made on pesticide use by farmers in five vegetable bases in Qujing city by questionnaires to study pesticide use and existing problems by farmers.[Result] Some problems existed in pesticide use in Qujing,such as non-standard pesticide source,lower-recognition of pesticide and impacts of pesticide residues on environment,and without professional guidance.[Conclusion] The existing problems can be resolved by enhancing technical trainings of technicians or pesticide managers,strengthening pesticide promotion,and reinforcing examination of pesticide residues. 展开更多
关键词 PESTICIDE RESIDUE control measures
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Discussion on the Soil and Water Conservation Model in Mountain Photovoltaic Power Generation Project
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作者 Aijun LIN Junwen TANG 《Asian Agricultural Research》 2024年第10期28-31,37,共5页
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
关键词 Mountain photovoltaic power generation Soil erosion Prevention and control measures Sustainable development
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Identification and Control of Paulownia fortunei Witches Broom Disease
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作者 李栋海 《Plant Diseases and Pests》 CAS 2010年第1期12-13,17,共3页
Pathogen and characteristics,occurrence law,damage symptom of Paulownia fortunei witches broom disease were simply described,and the control method of the disease was summarized.
关键词 Paulownia fortunei (seem.) Hemsi Witches broom disease PATHOGEN Occurrence status control measures
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Epidemiological characteristics of varicella in Chongqing,China,2014-2021
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作者 Yong-Jiao Hu Qing Wang +5 位作者 Mu-Nan Zhang Xin Zeng Quan-Hong Lu Zheng Zhang Ping Cheng Jing Deng 《Medical Data Mining》 2024年第2期32-38,共7页
Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control me... Background:To analyze the epidemiological characteristics of varicella epidemics in Chongqing Municipality from 2014 to 2021,and to provide a scientific basis for the formulation of varicella prevention and control measures.Methods:Data on the incidence of varicella outbreaks and vaccination data in Chongqing from 2014 to 2021 were collected through the China Disease Control and Prevention Information System and statistically analyzed using descriptive epidemiological methods.Results:From 2014 to 2021,213,715 cases of varicella were reported in Chongqing Municipality,with an average annual incidence rate of 86.26/100,000,with a statistically significant difference(χ^(2)=24,972.069,P<0.001);varicella incidence is seasonal,with peaks in May/June and October/December each year,presenting a“double-peak distribution”.The average annual incidence rate of varicella in municipal districts was 90.74/100,000,which was higher than that of counties 69.62/100,000 and autonomous counties 84.04/100,000;the average annual incidence rate of varicella in males was 89.37/100,000,and in females,82.22/100,000,with the difference not being statistically significant;the age of onset of the disease was mainly in the group of people under 15 years of age,with a total of 190,021 cases reported(88.9%),with 5-9 years old(35.7%)as the high incidence age group.The incidence occupation was dominated by students in 133,733 cases(62.6%).Conclusion:The overall varicella epidemic in Chongqing is on the rise,and has obvious seasonal,regional and population distribution characteristics.The prevention and control of varicella epidemic should be strengthened,the publicity of varicella vaccine should be increased,and it is recommended that varicella vaccine should be included in the national immunization program. 展开更多
关键词 VARICELLA epidemiologic characteristics VACCINATION preventive and control measures
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