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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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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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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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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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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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Damage by wind-blown sand and its control measures along the Taklimakan Desert Highway in China 被引量:15
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作者 LI Congjuan WANG Yongdong +4 位作者 LEI Jiaqiang XU Xinwen WANG Shijie FAN Jinglong LI Shengyu 《Journal of Arid Land》 SCIE CSCD 2021年第1期98-106,共9页
Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklima... Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts. 展开更多
关键词 wind-blown sand sand barrier fences artificial shelterbelt mechanical sand control measure biological sand control measure sustainable development Taklimakan Desert Highway
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CAUSES AND CONTROL COUNTERMEASURES OF EUTROPHICATION IN CHAOHU LAKE, CHINA 被引量:26
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作者 SHANG Guang-ping SHANG Jin-cheng 《Chinese Geographical Science》 SCIE CSCD 2005年第4期348-354,共7页
Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced... Chaohu Lake, located in the central Anhui Province, is one of the five largest fresh lakes in China. Now it is one of the three most eutrophication lakes in China. The deterioration of its water quality has influenced the sustainable development of society, economy and environment of Hefei City, the capital of Anhui Province. A series of measures have been carried out to control its eutrophication, but it is still serious. On the basis of the lake water quality data from 1984 to 2003, the causes of the eutrophication of Chaohu Lake are analyzed. Studies indicated that the suitable natural conditions and human activities played a crucial role in the process of the eutrophication of Chaohu Lake. A great amount of industrial, agricultural and domestic sewage discharged into the lake is the main cause of eutrophication in the lake. Land use, soil erosion and shoreline collapse destroyed the watershed eco-environment and the terrestrial ecosystem of Chaohu Lake. And the building of Yuxi Gate extends the sluggish of the nutritious substance and speeds up the process of the eutrophication. From the view of systematic engineering and watershed ecology, a series of the countermeasures have been put forward to control the eutrophication. 展开更多
关键词 causes of eutrophication eutrophication control non-engineering measures watershed management Chaohu Lake
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RESEARCH ON MECHANICAL MEASUREMENT-ORIENTED INTELLIGENT VIRTUAL CONTROLS 被引量:7
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作者 TangBaoping QinShuren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第3期356-359,共4页
Intelligent virtual control (IVC) is an intelligent measurement instrumentunit with the function of actual measurement instruments, and the unit can be used as basic buildingblock for a variety of more complex virtual... Intelligent virtual control (IVC) is an intelligent measurement instrumentunit with the function of actual measurement instruments, and the unit can be used as basic buildingblock for a variety of more complex virtual measurement instruments on a PC. IVC is a furtheradvancement from virtual instrument (VI), and it fuses the function modules and the controls modulesso that the relationship between the functions and controls of an instrument is imbedded in one ormore units. The design, implementation and optimization methods of IVCs are introduced. The computersoftware representation of IVCs is discussed. An example of an actual VI constructed with thebuilding blocks of IVCs is given. 展开更多
关键词 Mechanical measurement Intelligent virtual control (IVC) Virtualinstrument(VI)
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Consensus Control With a Constant Gain for Discrete-time Binary-valued Multi-agent Systems Based on a Projected Empirical Measure Method 被引量:5
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作者 Ting Wang Min Hu Yanlong Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期1052-1059,共8页
This paper studies the consensus control of multiagent systems with binary-valued observations.An algorithm alternating estimation and control is proposed.Each agent estimates the states of its neighbors based on a pr... This paper studies the consensus control of multiagent systems with binary-valued observations.An algorithm alternating estimation and control is proposed.Each agent estimates the states of its neighbors based on a projected empirical measure method for a holding time.Based on the estimates,each agent designs the consensus control with a constant gain at some skipping time.The states of the system are updated by the designed control,and the estimation and control design will be repeated.For the estimation,the projected empirical measure method is proposed for the binary-valued observations.The algorithm can ensure the uniform boundedness of the estimates and the mean square error of the estimation is proved to be at the order of the reciprocal of the holding time(the same order as that in the case of accurate outputs).For the consensus control,a constant gain is designed instead of the stochastic approximation based gain in the existing literature for binary-valued observations.And,there is no need to make modification for control since the uniform boundedness of the estimates ensures the uniform boundedness of the agents’states.Finally,the systems updated by the designed control are proved to achieve consensus and the consensus speed is faster than that in the existing literature.Simulations are given to demonstrate the theoretical results. 展开更多
关键词 Binary-valued observations CONSENSUS control CONSTANT GAIN convergence rate multi-agent systems projected empirical measure method
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Behavior Measurement Model Based on Prediction and Control of Trusted Network 被引量:5
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作者 Gong Bei Zhang Jianbiao +1 位作者 Shen Changxiang Zhang Xing 《China Communications》 SCIE CSCD 2012年第5期117-128,共12页
In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation... In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation,individual similarity function,group similarity function,direct trust assessment function,and generalized predictive control,this model can guarantee the trust of an end user and users in its network.Compared with traditional measurement model,the model considers different characteristics of various networks.The trusted measurement policies established according to different network environments have better adaptability.By constructing trusted group,the threats to trusted group will be reduced greatly.Utilizing trusted group to restrict individuals in network can ensure the fault tolerance of trustworthiness of trusted individuals and group.The simulation shows that this scheme can support behavior measurement more efficiently than traditional ones and the model resists viruses and Trojans more efficiently than older ones. 展开更多
关键词 trusted network behavioral predic-tive control SIMILARITY trust measurement
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Assessment on the Effects of Hepatitis B Prevention and Control Measures in Western China:A Comparison of Three Population-based Serosurveys 被引量:6
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作者 CHEN Hui LIU Nan +6 位作者 JI Zhao Hua PU Zhong Shu GUO Zhi Wen GAO Jie SHAO Zhong Jun LIU Yi Wen YAN Yong Ping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第10期735-744,共10页
Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in W... Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in Western China.This study aimed to evaluate the strategy of hepatitis B prevention and control in Western China and identify potential areas and strategies for improvement.Methods Susceptible population vaccination,health education,professional training of doctors,and other prevention and control measures have been implemented in Wuwei city since 2010.Data were obtained from three representative cross-sectional serosurveys conducted in 2010,2013,and 2015.The serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers:HBV surface antigen(HBsAg),antibody against hepatitis B surface antigen(anti-HBs),and antibody against hepatitis B core antigen(anti-HBc).Estimates of variance were determined using Taylor series linearization methods.Results The three serosurveys revealed decreases in the prevalence of HBsAg(7.19% in 2010 vs.6.51% in 2013 vs.5.87% in 2015)and anti-HBc positivity(43.89%vs.32.87%vs.28.46%)and an increase in the prevalence of anti-HBs positivity(49.07%vs.53.66%vs.53.72%)over time.From 2010 to 2015,the legally reported incidence of hepatitis B in Wuwei city decreased from 686.53/100,000 to 53.72/100,000.Notably,persistently high HBsAg-positive rates(above 5.40%)were observed among subjects aged 20–69 years old in the three serosurveys;the prevalence of HBsAg was above 1% among children younger than 10 years old.Furthermore,rural subjects had higher rates of HBsAg and anti-HBc positivity than their urban counterparts(6.04%vs.4.83% and 30.26%vs.20.35%,respectively)in 2015 but had a lower rate of anti-HBs positivity(49.68 vs.55.18%).Multivariate regression analysis showed that age,urban and rural areas,and education level were the main factors affecting HBV infection.Conclusion Although vaccine-based prevention and control measures reduced the rate of HBV infection in Wuwei City over time,the hepatitis B infection rate in children younger than 10 years was still higher than the national average level.Therefore,the prevention and control of mother-to-child transmission and the management of the infected should be the focus of future prevention and control work. 展开更多
关键词 Hepatitis B Prevention a n d control measures SEROSURVEY Western China
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Controlled teleportation of high-dimension quantumstates with generalized Bell-state measurement 被引量:2
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作者 詹佑邦 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第9期2557-2562,共6页
In this paper a scheme for controlled teleportation of arbitrary high-dimensional unknown quantum states is proposed by using the generalized Bell-basis measurement and the generalized Hadamard transformation. As two ... In this paper a scheme for controlled teleportation of arbitrary high-dimensional unknown quantum states is proposed by using the generalized Bell-basis measurement and the generalized Hadamard transformation. As two special cases, two schemes of controlled teleportation of an unknown single-qutrit state and an unknown two-qutrit state are investigated in detail. In the first scheme, a maximally entangled three-qutrit state is used as the quantum channel, while in the second scheme, an entangled two-qutrit state and an entangled three-qutrit state are employed as the quantum channels. In these schemes, an unknown qutrit state can be teleported to either one of two receivers, but only one of them can reconstruct the qutrit state with the help of the other. Based on the case of qutrits, a scheme of controlled teleportation of an unknown qudit state is presented. 展开更多
关键词 controlled teleportation high-dimensional quantum state generalized Bell-basis measurement generalized Hadamard transformation
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Quality control measures for lowering the seroconversion rate of hemodialysis patients with hepatitis B or C virus 被引量:2
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作者 Jing Yuan,Yi Yang, Fei Han, Ping Zhang, Xiao-Ying Du, Hua Jiang and Jiang-Hua Chen The Kidney Disease Center, First Affiliated Hospital, Zhejiang University School of Medicine (Yuan J, Yang Y, Han F, Zhang P, Du XY, Jiang H and Chen JH) and Hemodialysis Quality Control Center of Zhejiang Province (Yuan J, Zhang P, Du XY and Chen JH), Hangzhou 310003, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第3期302-306,共5页
BACKGROUND: Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the pre... BACKGROUND: Hemodialysis (HD) patients are at high risk of infection by hepatitis B virus (HBV) or hepatitis C virus (HCV). The present study was designed to determine the impact of quality control measures on the prevention of transmission of blood-borne viruses. METHODS: A total of 6182 adult maintenance HD patients from all HD units in Zhejiang Province were recruited on January 1, 2007. The baseline demographic and clinical characteristics were recorded and all patients were followed up until death or survival at 4 years later. The Quality Control Standards of Hemodialysis were gradually implemented in HD units. The HBV or HCV seroconversion rates of the recruited patients were calculated and compared every year during the observation period. RESULTS: The prevalence of HBV was 8.3% at the beginning of the study, and 6.6% for HCV. With the implementation of the HD quality control measures, the HBV seroconversion rate tended to decrease year by year (χ 2 =6.620, P=0.085), and the HCV seroconversion rate decreased significantly (χ 2 =10.41, P=0.015). Compared with the data in 2007, the HBV seroconversion rate (χ 2 =4.204, P=0.040, relative risk ratio 0.393, 95% CI 0.156-0.991) and the HCV seroconversion rate (χ 2 =7.373, P=0.007, relative risk ratio 0.386, 95% CI 0.189-0.787) decreased significantly in 2010. CONCLUSION: Quality control measures for HD decreased the seroconversion rates of HBV or HCV in HD patients, showing that updated quality control measures reduce the risk for transmission of blood-borne viruses in the HD population. 展开更多
关键词 HEMODIALYSIS quality control measures INFECTION hepatitis B virus hepatitis C virus
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A New Device for Gas-Liquid Flow Measurements Relying on Forced Annular Flow
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作者 Tiantian Yu Youping Lv +5 位作者 Hao Zhong Ming Liu Pingyuan Gai Zeju Jiang Peng Zhang Xingkai Zhang 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1759-1772,共14页
A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The sw... A new measurement device,consisting of swirling blades and capsule-shaped throttling elements,is proposed in this study to eliminate typical measurement errors caused by complex flow patterns in gas-liquid flow.The swirling blades are used to transform the complex flow pattern into a forced annular flow.Drawing on the research of existing blockage flow meters and also exploiting the single-phase flow measurement theory,a formula is introduced to measure the phase-separated flow of gas and liquid.The formula requires the pressure ratio,Lockhart-Martinelli number(L-M number),and the gas phase Froude number.The unknown parameters appearing in the formula are fitted through numerical simulation using computational fluid dynamics(CFD),which involves a comprehensive analysis of the flow field inside the device from multiple perspectives,and takes into account the influence of pressure fluctuations.Finally,the measurement model is validated through an experimental error analysis.The results demonstrate that the measurement error can be maintained within±8%for various flow patterns,including stratified flow,bubble flow,and wave flow. 展开更多
关键词 Gas-liquid flow measurement blocking flowmeter measurement model pressure fluctuations numerical simulation experimental control
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Current Status and Control Measures of Ecological Restoration in Karst Rocky Desertification Area of Guizhou 被引量:2
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作者 LIU Jian-zhong1,GUO Ying1,WANG Liu-ping1,HAN De-jun2 1.Guizhou Institute of Forestry Survey and Planning,Guiyang 550003,China 2.College of Resources and Environment,Guizhou College of Finance & Economics,Guiyang 550004,China 《Meteorological and Environmental Research》 CAS 2011年第5期61-64,共4页
[Objective] The aim was to analyze the current status and control measures of ecological restoration in Karst rocky desertification area of Guizhou.[Method] The current status and existing problems of ecological resto... [Objective] The aim was to analyze the current status and control measures of ecological restoration in Karst rocky desertification area of Guizhou.[Method] The current status and existing problems of ecological restoration in Karst rocky desertification area of Guizhou were studied firstly,and main control measures were put forward according to existing problems.[Result] At present,Karst rocky desertification area in Guizhou has suitable ecological environment,obvious control results and rich control experience,and there exist many problems like ambiguous concept of ecological restoration,biased control emphasis,single control measure and serious water shortage due to lagging engineering construction.Control measures mainly include combining natural restoration with artificial tending to speed up ecological restoration,reinforcing the restoration and rebuilding of development and construction project to prevent the deterioration of regional ecological environment,speeding up the construction of environmental friendly energy infrastructures to decrease the damage of vegetation by human activities,increasing industrial structure adjustment and greatly developing green industry and improving the investment in technological innovation to promote the rapid development of ecological restoration.[Conclusion] The study could provide scientific references for the ecological restoration in other Karst rocky desertification area in Southwest China. 展开更多
关键词 KARST DESERTIFICATION Ecological restoration control measures China
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Causes of Recurrence of Rice Chilo suppressalis( Walker) in Longyou County and Prevention and Control Measures 被引量:2
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作者 Ying WANG Yong ZHANG +3 位作者 Chenguang ZHANG Runzhong LOU Xinxin XU Xiaowei XU 《Asian Agricultural Research》 2019年第2期111-113,116,共4页
In recent years,the occurrence of rice Chilo suppressalis( Walker) in Longyou County of Zhejiang Province has increased year by year and has become aggravated. This poses a great threat to the safety of rice productio... In recent years,the occurrence of rice Chilo suppressalis( Walker) in Longyou County of Zhejiang Province has increased year by year and has become aggravated. This poses a great threat to the safety of rice production. In order to curb the recurrence momentum of rice C. suppressalis,according to the dynamic monitoring and field system survey of rice C. suppressalis in Longyou County since 2015,the causes of the annual increase of rice C. suppressalis in recent years were analyzed,and the recurrence area of C. suppressalis was introduced,and finally some prevention and control measures were put forward. 展开更多
关键词 CHILO SUPPRESSALIS (Walker) CAUSES of RECURRENCE Prevention and control measures
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H-infinity measurement-feedback control for discrete-time systems with a single measurement delay 被引量:1
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作者 Mei LIU Huanshui ZHANG Guangren DUAN 《控制理论与应用(英文版)》 EI 2006年第2期121-127,共7页
H-infinity control problem for linear discrete-time systems with instantaneous and delayed measurements is studied. A necessary and sufficient condition for the existence of the H-infinity controller is derived by app... H-infinity control problem for linear discrete-time systems with instantaneous and delayed measurements is studied. A necessary and sufficient condition for the existence of the H-infinity controller is derived by applying reorganized innovation analysis approach in Krein space. The measurement-feedback controller is designed by performing two Riccati equations. The presented approach does not require the state augmentation. 展开更多
关键词 H-infinity control Delayed measurement Discrete-time systems
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Current Situation and Comprehensive Control Measures of Water Environment in the Chaohu Lake 被引量:1
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作者 Hu Mingming Ma Jianhua Zhu Xi 《Meteorological and Environmental Research》 CAS 2016年第6期45-50,共6页
Based on the analysis of current situation of water environment in the Chaohu Lake,general ideas and measures of controlling the water environment were proposed. In respect of control ideas,controlling outbreaks of bl... Based on the analysis of current situation of water environment in the Chaohu Lake,general ideas and measures of controlling the water environment were proposed. In respect of control ideas,controlling outbreaks of blue-green algae should be as one of control goals; it is needed to combine reducing the quantity of blue-green algae with decreasing eutrophication level to make the decrease in the quantity of blue-green algae larger than their natural increase until outbreaks of blue-green algae are eliminated; all kinds of techniques should be combined closely,integrated and innovated,and corresponding safeguard measures should be adopted. In respect of control measures,controlling sources of pollution and intercepting pollutants are basic measures,of which improving sewage treatment capacity and standard greatly is a key measure,and actively controlling pollution from large-scale livestock and poultry breeding is one of main measures; rivers polluted heavily should be controlled,and using microorganisms to purify small and moderate rivers can be as one of preferred techniques; blue-green algae should be dredged deeply to reducing their quantity; water should be transferred from the Yangtze River to the Chaohu Lake or the Hauihe River to purify water bodies and increase environmental capacity; reed wetland should be restored on a large scale to increase vegetation coverage from 5% to 20%; dredging should be combined with the elevation of basement of restored reed wetland. 展开更多
关键词 The CHAOHU LAKE Water environment control measures CURRENT SITUATION China
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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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