Good vision is fundamental to human experience,profoundly influencing educational attainment,economic productivity and overall quality of life.Currently,it is estimated that at least 2.2 billion people globally suffer...Good vision is fundamental to human experience,profoundly influencing educational attainment,economic productivity and overall quality of life.Currently,it is estimated that at least 2.2 billion people globally suffer from vision impairment(VI),with over 1 billion of these cases being preventable or treatable yet remaining unaddressed.Despite significant advancements in global eye care services over the past few decades,which have yielded considerable benefits,the challenges continue to mount.展开更多
Ⅰ. INTRODUCTION Let A be a bounded linear operator on a separable infinitely-dimensional complex Hilbert space (?), denoted by A ∈(?)((?)), and lat A denote the lattice of all invariant subspaces of A. An operator A...Ⅰ. INTRODUCTION Let A be a bounded linear operator on a separable infinitely-dimensional complex Hilbert space (?), denoted by A ∈(?)((?)), and lat A denote the lattice of all invariant subspaces of A. An operator A is unicellular if lat A is totally ordered展开更多
AIM:To study the causal relationship between obesityrelated anthropometric traits and myopia and the mediating role of educational attainment(EA).METHODS:Univariable Mendelian randomization(UVMR)was performed to evalu...AIM:To study the causal relationship between obesityrelated anthropometric traits and myopia and the mediating role of educational attainment(EA).METHODS:Univariable Mendelian randomization(UVMR)was performed to evaluate the causal association between body mass index(BMI),height,waist-hip ratio(WHR,adjusted for BMI),and mean spherical equivalent(MSE).BMI was divided into fat and fat-free mass and included in multivariable Mendelian randomization(MVMR)to explore the roles of different BMI components in the causal relationship between BMI and MSE.A mediation analysis based on two-step Mendelian randomization(MR)was carried out.Specifically,UVMR was conducted to estimate the causal effect of BMI on EA.The direct effect of EA on MSE was estimated from MVMR.The mediation effect of EA in the BMI-EA-MSE model was calculated by the product of coefficients method.Expression quantitative trait loci(eQTL)-MR,reverse MR,and Linkage Disequilibrium Score Regression(LDSC)were performed to assess the robustness.RESULTS:Genetically predicted higher BMI had a positive total effect on MSE(βIVW=0.26 D,95%CI=0.14 to 0.37 D,P<0.001),whereas there was no significant association between height,WHR,and MSE.Fat mass was found to play a significant role in the effect of body mass on MSE(βIVW=0.50 D,95%CI=0.21 to 0.78 D,P=0.001),but there was no significant association between fat-free mass and MSE.The causal effect of BMI on EA was-0.14(95%CI=-0.16 to-0.11,P<0.001),and the direct effect of EA on MSE was-0.63 D(95%CI=-0.81 to-0.44 D,P<0.001).The mediating effect of EA in the BMI-EA-MSE model was 0.09 D(95%CI=0.06 to 0.12 D),with a mediation proportion of 33%(95%CI=22.1%to 44.6%).No reverse causal associations were detected except for BMI on EA.The results of eQTL-MR and LDSC were consistent with each MR analysis.CONCLUSION:Genetically predicted higher BMI decreases the degree of myopia with a 33%mediation proportion by EA,and fat mass provides a dominant protective role in body mass-myopia.As a supplement to previous observational studies,it provides strong evidence for the relationship between anthropometric traits and refractive errors and offers a theoretical basis for future measures to prevent and control myopia.展开更多
BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationsh...BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationship remain unelucidated.AIM To explore the causal associations between education,cognition,and intelligence and cholelithiasis,and the cardiometabolic risk factors that mediate the associations.METHODS Applying genome-wide association study summary statistics of primarily European individuals,we utilized two-sample multivariable Mendelian randomization to estimate the independent effects of education,intelligence,and cognition on cholelithiasis and cholecystitis(FinnGen study,37041 and 11632 patients,respectively;n=486484 participants)and performed two-step Mendelian randomization to evaluate 21 potential mediators and their mediating effects on the relationships between each exposure and cholelithiasis.RESULTS Inverse variance weighted Mendelian randomization results from the FinnGen consortium showed that genetically higher education,cognition,or intelligence were not independently associated with cholelithiasis and cholecystitis;when adjusted for cholelithiasis,higher education still presented an inverse effect on cholecystitis[odds ratio:0.292(95%CI:0.171-0.501)],which could not be induced by cognition or intelligence.Five out of 21 cardiometabolic risk factors were perceived as mediators of the association between education and cholelithiasis,including body mass index(20.84%),body fat percentage(40.3%),waist circumference(44.4%),waist-to-hip ratio(32.9%),and time spent watching television(41.6%),while time spent watching television was also a mediator from cognition(20.4%)and intelligence to cholelithiasis(28.4%).All results were robust to sensitivity analyses.CONCLUSION Education,cognition,and intelligence all play crucial roles in the development of cholelithiasis,and several cardiometabolic mediators have been identified for prevention of cholelithiasis due to defects in each exposure.展开更多
Objective:To explore the effect of King’s Theory of Goal Attainment combined with teach-back method on improving the standardization rate of eye drop use in patients.Methods:A total of 200 patients who used more than...Objective:To explore the effect of King’s Theory of Goal Attainment combined with teach-back method on improving the standardization rate of eye drop use in patients.Methods:A total of 200 patients who used more than two types of eye drops in the Department of Ophthalmology of our hospital were selected as the research subjects,and were randomly divided into an observation group and a control group.The control group was given routine health education,while the observation group was given King’s Theory of Goal Attainment combined with teach-back method on the basis of the control group.The standardization rate of eye drop use,knowledge awareness rate,and nursing satisfaction were compared between the two groups before and after the intervention.Results:After the intervention,the standardization rate of eye drop use,the awareness rate of eye drop knowledge,and the nursing satisfaction of the observation group were significantly higher than those of the control group(P<0.05).Conclusion:King’s Theory of Goal Attainment combined with teach-back method can effectively improve the standardization rate of eye drop use in patients,increase their awareness of eye drop knowledge,and improve nursing satisfaction,which is worthy of clinical application.展开更多
Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a ...Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a total of 5408 field experiments were collected from 2000 to 2015 across the major wheat production regions in China to analyze the spatial distribution of wheat yield,the soil nutrient supply capacity(represented by relative yield,defined as the ratio of the yield under the omission of one of nitrogen(N),phosphorus(P)and potassium(K)to the yield under the full NPK fertilizer application),and N,P and K fertilizer requirements by combining the kriging interpolation method with the Nutrient Expert Decision Support System for Wheat.The results indicated that the average attainable yield was 6.4 t ha^(−1),with a coefficient of variation(CV)of 24.9% across all sites.The yields in North-central China(NCC)and the northern part of the Middle and Lower reaches of the Yangtze River(MLYR)were generally higher than 7 t ha^(−1),whereas the yields in Southwest China(SWC),Northeast China(NEC),and the eastern part of Northwest China(NWC)were usually less than 6 t ha^(−1).The precentage of area having a relative yield above 0.70,0.85,and 0.85 for N,P,and K fertilizers accounted for 52.3,74.7,and 95.9%,respectively.Variation existed in N,P,and K fertilizer requirements,with a CV of 24.8,23.9,and 29.9%,respectively,across all sites.More fertilizer was needed in NCC and the northern part of the MLYR than in other regions.The average fertilizer requirement was 162,72,and 57 kg ha^(−1) for N,P2O5,and K2O fertilizers,respectively,across all sites.The incorporation of the spatial variation of attainable yield and fertilizer requirements into wheat production practices would benefit sustainable wheat production and environmental safety.展开更多
Control allocation considers the problem of controlling instruction distribution for control systems with multiple and redundant actuators. This paper focuses on the direct allocation method, making the time requireme...Control allocation considers the problem of controlling instruction distribution for control systems with multiple and redundant actuators. This paper focuses on the direct allocation method, making the time requirement of the algorithm analogous compared with modified pseudoinverse redistribution methods, linear programming methods solved by simplex method, and sub-gradient optimization method. To reduce off-line computations of constructing the attainable moment set of actuators, a new approach based on the null space of the control effectiveness matrix is proposed, which is superior when the number of actuators is less than 10 compared with traditional method. To decrease on-line computations, an improvement method of searching the facet that is aligned with the desired moment is presented, shortening the search time by checking only the facets that lie around the desired moment. To find such facets, the vertices of the attainable moment set are normalized and saved during off-line computations. Simulation results show that at least 32.22% of off-line computation time would be saved using null space-based construction when the number of actuators is less than 10. In on-line computations, the modified method performs superiorly compared with the three aforementioned methods. Furthermore, it may solve the problem of control allocation efficiently when a remarkable large number of redundant actuators are configured.展开更多
This paper presents a methodology for evaluating the water purification process efficiency attained by 1) jar tests, which are commonly used to determine the treatability of water, and 2) waterworks performance in dif...This paper presents a methodology for evaluating the water purification process efficiency attained by 1) jar tests, which are commonly used to determine the treatability of water, and 2) waterworks performance in different phases of the purification process as well as in its entirety. This methodology provides an important tool for the following: 1) determination of optimised reaction conditions under which water is treatable to its best attainable quality;2) evaluation of the purification process efficiency attained by waterworks during different periods and under different operational conditions;3) comparisons of performance efficiency of different waterworks;and 4) comprehensive commissioning of waterworks and identification of bottlenecks if any exist in process and plant design. This paper describes procedures for pre-processing of water samples to be analysed as well as mathematical formulas for processing of the results obtained. A few examples of the practical application of the methodology are included and the potential to obtain the optimization of waterworks’ purification processes is herein illustrated.展开更多
Background Coronary artery disease （CAD） is a leading cause of death in elderly because aging is the important non-modifiable risk factors of atherosclerosis and also a predictor of poor outcomes. Underuse of guidel...Background Coronary artery disease （CAD） is a leading cause of death in elderly because aging is the important non-modifiable risk factors of atherosclerosis and also a predictor of poor outcomes. Underuse of guideline directed therapy may contribute to suboptimal risk factor control and worse outcomes in the elderly. We aimed to explore the management of CAD, risk factors control as well as goal attain- ment in elderly compared to nonelderly CAD patients. Methods The CORE-Thailand is an ongoing multicenter, prospective, observational registry of patients with high atherosclerotic risk in Thailand. The data of 4120 CAD patients enrolled in this cohort was analyzed comparing between the elderly （age ≥ 65 years） vs. nonelderly （age 〈 65 years）. Results There were 2172 elderly and 1948 nonelderly patients. The elderly CAD patients had higher prevalence of hypertension, dyslipidemia, atrial fibrillation and chronic kidney disease. The proportion of patients who received coronary revascularization was not different between the elderly and nonelderly CAD patients. Antiplatelets were prescribed less in the elderly while statin was prescribed in the similar proportion. Goal attainments of risk factor control of glycemic control, low density lipoprotein cholesterol, and smoking cessation except the blood pressure goal were higher in the elderly CAD patients. Conclusions The CORE-Thailand registry showed the equity in the treatment of CAD between elderly and non-elderly. Elderly CAD patients had higher rate of goal attainment in risk factor control except blood pressure goal. The effects of goal attainment on cardiovascular outcomes will be demonstrated from ongoing cohort.展开更多
In this paper, the research was focused on optimizing low-temperature heat recovery to adopt multi-effect distil- lation （MED） in desalination by pinch technology. And further analysis indicated that phase changes o...In this paper, the research was focused on optimizing low-temperature heat recovery to adopt multi-effect distil- lation （MED） in desalination by pinch technology. And further analysis indicated that phase changes occurred during the heat recovery process. In such case, the feed stream was divided into two streams： the liquid feed stream and the gaseous feed stream. Through calculation, the optimal ATmin was established at 26℃, and the total cost of heat exchange process was only $1.098× 106. By using the Problem Table Algorithm for pinch analysis, the temperature of the hot and the cold steams was 119℃ and 93 ℃, respectively. At a temperature higher than 119 ℃, all heat of the hot stream could not be cooled by the condenser, and the minimum heat load of utility （QH.min） was 440457.64 kW; and at a temperature below 93 ℃, all heat of the cold stream could not be provided by the heater, and the minimum cold load of utility （QC.min） was 1965993.85 kW. Finally, the synthesis of heat exchanger network was established through integrating two heat exchanger networks.展开更多
Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Comm...Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition （SMAT-CE） is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards （NAAQS） shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.展开更多
This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streaml...This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_（2.5） attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_（2.5） to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition（SMAT-CE）,and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta（YRD） in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality（CMAQ） model simulation results with maximum mean normalized error 〈 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_（2.5） in January and August（e.g.,more than50%contributed by primary emissions in Shanghai）,and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China＇s annual PM_（2.5）National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_（2.5）（and potentially O_3 as well） and streamline air quality data for SMAT-CE to perform attainment assessments.展开更多
In order to improve the transform efficiency of bi-stable energy harvester（BEH）,this paper proposes an advanced bi-stable energy harvester（ABEH）,which is composed of two bi-stable beams coupling through their magn...In order to improve the transform efficiency of bi-stable energy harvester（BEH）,this paper proposes an advanced bi-stable energy harvester（ABEH）,which is composed of two bi-stable beams coupling through their magnets.Theoretical analyzes and simulations for the ABEH are carried out.First,the mathematical model is established and its dynamical equations are derived.The formulas of magnetic force in two directions are given.The potential energy barrier of ABEH is reduced and the snap-through is liable to occur between potential wells.To demonstrate the ABEH＇s advantage in harvesting energy,comparisons between the ABEH and the BEH are carried out for both harmonic and stochastic excitations.Our results reveal that the ABEH＇s inter-well response can be elicited by a low-frequency excitation and the harvester can attain frequent jumping between potential wells at fairly weak random excitations.Thus,it can generate a higher output power.The present findings prove that the ABEH is preferable in harvesting energy and can be optimally designed such that it attains the best harvesting performance.展开更多
English as a popular foreign language in China is learned by many students.The attainment is often considered and talked.There are many factors which affect the learning outcomes. This essay will give a brief introduc...English as a popular foreign language in China is learned by many students.The attainment is often considered and talked.There are many factors which affect the learning outcomes. This essay will give a brief introduction of the aspects concerning the evidence for the relationship between attainment and learner variables.展开更多
Since the 1970′s a steady 2—day wave has been detected in the mesosphere and lowthermosphere by many observations such as meteor radar,partial reflection driftradar,means of satellite radiance measurements and rocke...Since the 1970′s a steady 2—day wave has been detected in the mesosphere and lowthermosphere by many observations such as meteor radar,partial reflection driftradar,means of satellite radiance measurements and rocket measurements.It has beenrevealed that 2—day wave travels westwards with longitudinal wave number three and theinferred vertical wave length of the wave is in excess of 100km.If a global scale展开更多
This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristo...This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of the security margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid off and an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed.展开更多
文摘Good vision is fundamental to human experience,profoundly influencing educational attainment,economic productivity and overall quality of life.Currently,it is estimated that at least 2.2 billion people globally suffer from vision impairment(VI),with over 1 billion of these cases being preventable or treatable yet remaining unaddressed.Despite significant advancements in global eye care services over the past few decades,which have yielded considerable benefits,the challenges continue to mount.
文摘Ⅰ. INTRODUCTION Let A be a bounded linear operator on a separable infinitely-dimensional complex Hilbert space (?), denoted by A ∈(?)((?)), and lat A denote the lattice of all invariant subspaces of A. An operator A is unicellular if lat A is totally ordered
基金Supported by Hubei Province Key Research and Development Program Project,Hubei Provincial Department of Science and Technology(No.2022BCA044)Key Scientific Research Projects of Health Commission of Hubei Province in 2023-2024,Health Commission of Hubei Province(No.WJ2023Z006).
文摘AIM:To study the causal relationship between obesityrelated anthropometric traits and myopia and the mediating role of educational attainment(EA).METHODS:Univariable Mendelian randomization(UVMR)was performed to evaluate the causal association between body mass index(BMI),height,waist-hip ratio(WHR,adjusted for BMI),and mean spherical equivalent(MSE).BMI was divided into fat and fat-free mass and included in multivariable Mendelian randomization(MVMR)to explore the roles of different BMI components in the causal relationship between BMI and MSE.A mediation analysis based on two-step Mendelian randomization(MR)was carried out.Specifically,UVMR was conducted to estimate the causal effect of BMI on EA.The direct effect of EA on MSE was estimated from MVMR.The mediation effect of EA in the BMI-EA-MSE model was calculated by the product of coefficients method.Expression quantitative trait loci(eQTL)-MR,reverse MR,and Linkage Disequilibrium Score Regression(LDSC)were performed to assess the robustness.RESULTS:Genetically predicted higher BMI had a positive total effect on MSE(βIVW=0.26 D,95%CI=0.14 to 0.37 D,P<0.001),whereas there was no significant association between height,WHR,and MSE.Fat mass was found to play a significant role in the effect of body mass on MSE(βIVW=0.50 D,95%CI=0.21 to 0.78 D,P=0.001),but there was no significant association between fat-free mass and MSE.The causal effect of BMI on EA was-0.14(95%CI=-0.16 to-0.11,P<0.001),and the direct effect of EA on MSE was-0.63 D(95%CI=-0.81 to-0.44 D,P<0.001).The mediating effect of EA in the BMI-EA-MSE model was 0.09 D(95%CI=0.06 to 0.12 D),with a mediation proportion of 33%(95%CI=22.1%to 44.6%).No reverse causal associations were detected except for BMI on EA.The results of eQTL-MR and LDSC were consistent with each MR analysis.CONCLUSION:Genetically predicted higher BMI decreases the degree of myopia with a 33%mediation proportion by EA,and fat mass provides a dominant protective role in body mass-myopia.As a supplement to previous observational studies,it provides strong evidence for the relationship between anthropometric traits and refractive errors and offers a theoretical basis for future measures to prevent and control myopia.
文摘BACKGROUND Education,cognition,and intelligence are associated with cholelithiasis occurrence,yet which one has a prominent effect on cholelithiasis and which cardiometabolic risk factors mediate the causal relationship remain unelucidated.AIM To explore the causal associations between education,cognition,and intelligence and cholelithiasis,and the cardiometabolic risk factors that mediate the associations.METHODS Applying genome-wide association study summary statistics of primarily European individuals,we utilized two-sample multivariable Mendelian randomization to estimate the independent effects of education,intelligence,and cognition on cholelithiasis and cholecystitis(FinnGen study,37041 and 11632 patients,respectively;n=486484 participants)and performed two-step Mendelian randomization to evaluate 21 potential mediators and their mediating effects on the relationships between each exposure and cholelithiasis.RESULTS Inverse variance weighted Mendelian randomization results from the FinnGen consortium showed that genetically higher education,cognition,or intelligence were not independently associated with cholelithiasis and cholecystitis;when adjusted for cholelithiasis,higher education still presented an inverse effect on cholecystitis[odds ratio:0.292(95%CI:0.171-0.501)],which could not be induced by cognition or intelligence.Five out of 21 cardiometabolic risk factors were perceived as mediators of the association between education and cholelithiasis,including body mass index(20.84%),body fat percentage(40.3%),waist circumference(44.4%),waist-to-hip ratio(32.9%),and time spent watching television(41.6%),while time spent watching television was also a mediator from cognition(20.4%)and intelligence to cholelithiasis(28.4%).All results were robust to sensitivity analyses.CONCLUSION Education,cognition,and intelligence all play crucial roles in the development of cholelithiasis,and several cardiometabolic mediators have been identified for prevention of cholelithiasis due to defects in each exposure.
基金Maoming Science and Technology Plan Project(2022182)。
文摘Objective:To explore the effect of King’s Theory of Goal Attainment combined with teach-back method on improving the standardization rate of eye drop use in patients.Methods:A total of 200 patients who used more than two types of eye drops in the Department of Ophthalmology of our hospital were selected as the research subjects,and were randomly divided into an observation group and a control group.The control group was given routine health education,while the observation group was given King’s Theory of Goal Attainment combined with teach-back method on the basis of the control group.The standardization rate of eye drop use,knowledge awareness rate,and nursing satisfaction were compared between the two groups before and after the intervention.Results:After the intervention,the standardization rate of eye drop use,the awareness rate of eye drop knowledge,and the nursing satisfaction of the observation group were significantly higher than those of the control group(P<0.05).Conclusion:King’s Theory of Goal Attainment combined with teach-back method can effectively improve the standardization rate of eye drop use in patients,increase their awareness of eye drop knowledge,and improve nursing satisfaction,which is worthy of clinical application.
基金This research was supported by the National Key R&D Program of China(2016YFD0200101)the National Natural Science Foundation of China(31801938).
文摘Quantification of currently attainable yield and fertilizer requirements can provide detailed information for assessing the food supply capacity and offer data support for agricultural decision-making.Datasets from a total of 5408 field experiments were collected from 2000 to 2015 across the major wheat production regions in China to analyze the spatial distribution of wheat yield,the soil nutrient supply capacity(represented by relative yield,defined as the ratio of the yield under the omission of one of nitrogen(N),phosphorus(P)and potassium(K)to the yield under the full NPK fertilizer application),and N,P and K fertilizer requirements by combining the kriging interpolation method with the Nutrient Expert Decision Support System for Wheat.The results indicated that the average attainable yield was 6.4 t ha^(−1),with a coefficient of variation(CV)of 24.9% across all sites.The yields in North-central China(NCC)and the northern part of the Middle and Lower reaches of the Yangtze River(MLYR)were generally higher than 7 t ha^(−1),whereas the yields in Southwest China(SWC),Northeast China(NEC),and the eastern part of Northwest China(NWC)were usually less than 6 t ha^(−1).The precentage of area having a relative yield above 0.70,0.85,and 0.85 for N,P,and K fertilizers accounted for 52.3,74.7,and 95.9%,respectively.Variation existed in N,P,and K fertilizer requirements,with a CV of 24.8,23.9,and 29.9%,respectively,across all sites.More fertilizer was needed in NCC and the northern part of the MLYR than in other regions.The average fertilizer requirement was 162,72,and 57 kg ha^(−1) for N,P2O5,and K2O fertilizers,respectively,across all sites.The incorporation of the spatial variation of attainable yield and fertilizer requirements into wheat production practices would benefit sustainable wheat production and environmental safety.
基金National Natural Science Foundation of China （NSFC60704020） Changjiang Scholars and Innovative Research Team of China （PCSIRT0520） Research Fund for the Doctoral Program of Higher Education of China （20070213068）
文摘Control allocation considers the problem of controlling instruction distribution for control systems with multiple and redundant actuators. This paper focuses on the direct allocation method, making the time requirement of the algorithm analogous compared with modified pseudoinverse redistribution methods, linear programming methods solved by simplex method, and sub-gradient optimization method. To reduce off-line computations of constructing the attainable moment set of actuators, a new approach based on the null space of the control effectiveness matrix is proposed, which is superior when the number of actuators is less than 10 compared with traditional method. To decrease on-line computations, an improvement method of searching the facet that is aligned with the desired moment is presented, shortening the search time by checking only the facets that lie around the desired moment. To find such facets, the vertices of the attainable moment set are normalized and saved during off-line computations. Simulation results show that at least 32.22% of off-line computation time would be saved using null space-based construction when the number of actuators is less than 10. In on-line computations, the modified method performs superiorly compared with the three aforementioned methods. Furthermore, it may solve the problem of control allocation efficiently when a remarkable large number of redundant actuators are configured.
文摘This paper presents a methodology for evaluating the water purification process efficiency attained by 1) jar tests, which are commonly used to determine the treatability of water, and 2) waterworks performance in different phases of the purification process as well as in its entirety. This methodology provides an important tool for the following: 1) determination of optimised reaction conditions under which water is treatable to its best attainable quality;2) evaluation of the purification process efficiency attained by waterworks during different periods and under different operational conditions;3) comparisons of performance efficiency of different waterworks;and 4) comprehensive commissioning of waterworks and identification of bottlenecks if any exist in process and plant design. This paper describes procedures for pre-processing of water samples to be analysed as well as mathematical formulas for processing of the results obtained. A few examples of the practical application of the methodology are included and the potential to obtain the optimization of waterworks’ purification processes is herein illustrated.
文摘Background Coronary artery disease （CAD） is a leading cause of death in elderly because aging is the important non-modifiable risk factors of atherosclerosis and also a predictor of poor outcomes. Underuse of guideline directed therapy may contribute to suboptimal risk factor control and worse outcomes in the elderly. We aimed to explore the management of CAD, risk factors control as well as goal attain- ment in elderly compared to nonelderly CAD patients. Methods The CORE-Thailand is an ongoing multicenter, prospective, observational registry of patients with high atherosclerotic risk in Thailand. The data of 4120 CAD patients enrolled in this cohort was analyzed comparing between the elderly （age ≥ 65 years） vs. nonelderly （age 〈 65 years）. Results There were 2172 elderly and 1948 nonelderly patients. The elderly CAD patients had higher prevalence of hypertension, dyslipidemia, atrial fibrillation and chronic kidney disease. The proportion of patients who received coronary revascularization was not different between the elderly and nonelderly CAD patients. Antiplatelets were prescribed less in the elderly while statin was prescribed in the similar proportion. Goal attainments of risk factor control of glycemic control, low density lipoprotein cholesterol, and smoking cessation except the blood pressure goal were higher in the elderly CAD patients. Conclusions The CORE-Thailand registry showed the equity in the treatment of CAD between elderly and non-elderly. Elderly CAD patients had higher rate of goal attainment in risk factor control except blood pressure goal. The effects of goal attainment on cardiovascular outcomes will be demonstrated from ongoing cohort.
基金the National Nature Science Foundation (Grant No. 51178463)
文摘In this paper, the research was focused on optimizing low-temperature heat recovery to adopt multi-effect distil- lation （MED） in desalination by pinch technology. And further analysis indicated that phase changes occurred during the heat recovery process. In such case, the feed stream was divided into two streams： the liquid feed stream and the gaseous feed stream. Through calculation, the optimal ATmin was established at 26℃, and the total cost of heat exchange process was only $1.098× 106. By using the Problem Table Algorithm for pinch analysis, the temperature of the hot and the cold steams was 119℃ and 93 ℃, respectively. At a temperature higher than 119 ℃, all heat of the hot stream could not be cooled by the condenser, and the minimum heat load of utility （QH.min） was 440457.64 kW; and at a temperature below 93 ℃, all heat of the cold stream could not be provided by the heater, and the minimum cold load of utility （QC.min） was 1965993.85 kW. Finally, the synthesis of heat exchanger network was established through integrating two heat exchanger networks.
基金provided by the U.S. Environmental Protection Agency (Subcontract Number OR13810-001.04 A10-0223-S001-A04)partly supported by the funding of Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control (No. 2011A060901011)+1 种基金the funding of State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex (No. SCAPC201308)the project of Atmospheric Haze Collaborative Control System Design (No. XDB05030400) from Chinese Academy of Sciences
文摘Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition （SMAT-CE） is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards （NAAQS） shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.
基金Financial support and data source for this work is provided by the US Environmental Protection Agency(No.OR13810-001.04 A10-0223-S001-A02)Guangzhou Environmental Protection Bureau(No.x2hj B2150020)+4 种基金the project of an integrated modeling and filed observational verification on the deposition of typical industrial point-source mercury emissions in the Pearl River Deltapartly supported by the funding of Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control(No.2011A060901011)the project of Atmospheric Haze Collaboration Control Technology Design(No.XDB05030400)from the Chinese Academy of Sciencesthe Ministry of Environmental Protection's Special Funds for Research on Public Welfare(No.201409002)Partly financial support is also provided by the Guangdong Provincial Department of Science and Technology,the project of demonstration research of air quality management cost-benefit analysis and attainment assessments technology(No.2014A050503019)
文摘This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_（2.5） attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_（2.5） to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition（SMAT-CE）,and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta（YRD） in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality（CMAQ） model simulation results with maximum mean normalized error 〈 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_（2.5） in January and August（e.g.,more than50%contributed by primary emissions in Shanghai）,and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China＇s annual PM_（2.5）National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_（2.5）（and potentially O_3 as well） and streamline air quality data for SMAT-CE to perform attainment assessments.
基金Project supported by the National Natural Science Foundation of China(Grant No.11172234)the Scholarship from China Scholarship Council(Grant No.201506290092)
文摘In order to improve the transform efficiency of bi-stable energy harvester（BEH）,this paper proposes an advanced bi-stable energy harvester（ABEH）,which is composed of two bi-stable beams coupling through their magnets.Theoretical analyzes and simulations for the ABEH are carried out.First,the mathematical model is established and its dynamical equations are derived.The formulas of magnetic force in two directions are given.The potential energy barrier of ABEH is reduced and the snap-through is liable to occur between potential wells.To demonstrate the ABEH＇s advantage in harvesting energy,comparisons between the ABEH and the BEH are carried out for both harmonic and stochastic excitations.Our results reveal that the ABEH＇s inter-well response can be elicited by a low-frequency excitation and the harvester can attain frequent jumping between potential wells at fairly weak random excitations.Thus,it can generate a higher output power.The present findings prove that the ABEH is preferable in harvesting energy and can be optimally designed such that it attains the best harvesting performance.
文摘English as a popular foreign language in China is learned by many students.The attainment is often considered and talked.There are many factors which affect the learning outcomes. This essay will give a brief introduction of the aspects concerning the evidence for the relationship between attainment and learner variables.
文摘Since the 1970′s a steady 2—day wave has been detected in the mesosphere and lowthermosphere by many observations such as meteor radar,partial reflection driftradar,means of satellite radiance measurements and rocket measurements.It has beenrevealed that 2—day wave travels westwards with longitudinal wave number three and theinferred vertical wave length of the wave is in excess of 100km.If a global scale
文摘This paper presents a novel approach to find optimum locations and capacity of flexible alternating current transmission system (FACTS) devices in a power system using a multi-objective optimization function. Thyristor controlled series compensators (TCSCs) and static var compensators (SVCs) are the utilized FACTS devices. Our objectives are active power loss reduction, newly introduced FACTS devices cost reduction, voltage deviation reduction, and increase on the robustness of the security margin against voltage collapse. The operational and controlling constraints, as well as load constraints, were considered in the optimum allocation. A goal attainment method based on the genetic algorithm (GA) was used to approach the global optimum. The estimated annual load profile was utilized in a sequential quadratic programming (SQP) optimization sub-problem to the optimum siting and sizing of FACTS devices. Fars Regional Electric Network was selected as a practical system to validate the performance and effectiveness of the proposed method. The entire investment of the FACTS devices was paid off and an additional 2.4% savings was made. The cost reduction of peak point power generation implies that power plant expansion can be postponed.
