Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction safety.This paper proposes a modified back analysis method with multi-objective ...Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction safety.This paper proposes a modified back analysis method with multi-objective optimization procedure,which enables a real-time prediction of horizontal displacement of retaining pile during construction.As opposed to the traditional stage-by-stage back analysis,time series monitoring data till the current excavation stage are utilized to form a multi-objective function.Then,the multi-objective particle swarm optimization (MOPSO) algorithm is applied for parameter identification.The optimized model parameters are immediately adopted to predict the excavation-induced pile deformation in the continuous construction stages.To achieve efficient parameter optimization and real-time prediction of system behavior,the back propagation neural network (BPNN) is established to substitute the finite element model,which is further implemented together with MOPSO for automatic operation.The proposed approach is applied in the Taihu tunnel excavation project,where the effectiveness of the method is demonstrated via the comparisons with the site monitoring data.The method is reliable with a prediction accuracy of more than 90%.Moreover,different optimization algorithms,including non-dominated sorting genetic algorithm (NSGA-II),Pareto Envelope-based Selection Algorithm II (PESA-II) and MOPSO,are compared,and their influences on the prediction accuracy at different excavation stages are studied.The results show that MOPSO has the best performance for high dimensional optimization task.展开更多
The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.Howev...The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.展开更多
With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality de...With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality development of the regional economy,industrial policies are increasingly receiving attention in terms of their role and impact.This article mainly conducts an in-depth analysis of the mechanism and impact path of industrial policies,exploring the role and impact of industrial policies in promoting high-quality regional economic development.Firstly,industrial policies play an important role in promoting high-quality regional economic development.Secondly,the impact path of industrial policies on the high-quality development of the regional economy mainly includes promoting industrial structure upgrading,promoting technological innovation,guiding resource allocation,and enhancing enterprise competitiveness.Therefore,it is necessary to increase research and practice on industrial policies,continuously optimize policy measures,and promote high-quality development of the regional economy.展开更多
The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enri...The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enriches course materials,integrates teacher resources,improves students’participation in innovation and entrepreneurship,and solves problems such as low student participation,lack of course resources,insufficient teacher resources,and single evaluation methods in traditional classrooms.Through various means such as exploring course resources,innovating management models,and strengthening team construction,the role of“one-stop”student communities in innovation and entrepreneurship education has been fully utilized,promoting the development of innovation and entrepreneurship education.展开更多
The pressurizing pipeline of hot press resonates under the excitation load,which poses a serious hidden danger to the safety of the equipment and the operator.In order to increase the natural frequency of the pressuri...The pressurizing pipeline of hot press resonates under the excitation load,which poses a serious hidden danger to the safety of the equipment and the operator.In order to increase the natural frequency of the pressurizing pipeline,modal analysis of the pressurizing pipeline is carried out to study the mechanism of pipeline vibration and common vibration reduction measures.A method of increasing the natural frequency of the pressurizing pipeline was analyzed.The influence of pipeline clamp assembly stiffness,pipeline clamp number and pipeline clamp installation position on the mode of the pressurizing pipeline is studied.Sensitivity analysis is carried out to study the influence of the various parameters on the mode of the pressurizing pipeline.Genetic algorithm based on Pareto optimality is introduced for multi-objective optimization of pressurizing pipeline.The optimization results show that the natural frequency of the pressurizing pipeline increases by 2.4%and the displacement response is reduced by 17.7%.展开更多
120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis...120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated (P 〈 0.05). Total weight was significantly and positively correlated with shell weight (r = 0.8970), shell height (r = 0.6974), shell width (r = 0.6521) and shell length (r = 0.5486). Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits (shell length, shell width, shell height, shell weight and total wet weigh) of the F1 population could be improved by direct or indirect selection.展开更多
Driven by the goal of“carbon neutrality,”the increase in use of renewable energy power systems will be inevitable in the future.Uncontrolled output power and random volatility make it difficult to balance power in r...Driven by the goal of“carbon neutrality,”the increase in use of renewable energy power systems will be inevitable in the future.Uncontrolled output power and random volatility make it difficult to balance power in real time during system operation.Therefore,energy storage is considered to be an effective way to ensure the real-time balance of system power.However,cost of energy storage is relatively expensive.As a solution,energy storage can be used to balance the system power in order to reduce system operating costs.Taking the high proportion of wind power systems as an example,the impact of the“supply side”low-carbon transformation on the economics and reliability of power system operation is explored.In order to solve the problem of power system operation configuration optimization under the background of“carbon neutrality,”this paper establishes a multi-objective programming model.展开更多
In April of 2006, a base population of the noble scallop Chlamys nobilis was established by collecting parental breeders from the stocks in Wushi, Zhanjiang. In December of 2006, 200 individuals were randomly sampled ...In April of 2006, a base population of the noble scallop Chlamys nobilis was established by collecting parental breeders from the stocks in Wushi, Zhanjiang. In December of 2006, 200 individuals were randomly sampled from the base population and subjected for correlation and path coefficient analysis. It was found that there were statistically significant phenotypic correlations among the traits (P 〈 0.01). Total weight was significantly and positively correlated with the shell length (r = 0.934 3), shell height (r = 0.895 9), shell width (r = 0.899 1 ), muscle weight (r = 0.882 0) and shell weight (r = 0.937 9), respectively. Shell length, shell width, muscle weight, shell height and shell weight had positive and direct effects on the total weight, with values of 0.397 1, 0.321 9, 0.172 1, 0.089 6 and 0.066 9, respectively. Shell length, shell width and muscle weight had higher direct effects on the total weight than shell height and shell weight. A combined evaluation of correlation, direct effects and indirect effects showed that direct selection for shell length, shell width, muscle weight, shell height and shell weight would be effective to improving the total weight. It was concluded that these traits could be regarded as the selection criteria in breeding programs of the species.展开更多
[Objective] This study was tween yield-related traits and yield of conducted to understand the relationship be- Yunmai 52 which is a high-quality high-yield multi-resistant new wheat variety, and make contribution of ...[Objective] This study was tween yield-related traits and yield of conducted to understand the relationship be- Yunmai 52 which is a high-quality high-yield multi-resistant new wheat variety, and make contribution of yield-related traits to the yield of Yunmai 52 clear. [Method] Wheat variety regional trial data in Yunnan Province in 2005-2007 were subjected to correlation analysis and path analysis in the paper. [Result] Correlationanalysis showed that the yield of Yunmai 52 was in- very significant positive correlation with spikelet number per ear, maximum tiller number and grains per ear (r=0.726^**, 0.717^** and 0.695^**, respectively), in signif- icant positive correlation with 1 000-grain weight (r=0.491^*), but in significant nega- tive correlation with sterile spikelet number per ear, and in non-significant correlation with basic seedlings, effective ears and percentage of ear bearing tillers. Partial correlation analysis showed that the yield of Yunmai 52 was in very significant posi- tive correlation with spikelet number per ear (r=0.711^**), significant positive correla- tion with 1 000-grain weight (r=0.641 =), but in non-significant correlation with other 6 traits. Path analysis showed that spikelet number per ear (P=-0.595), maximum tiller number (P=0.462) and t 000-grain weight (P=0.263) had more contribution to yield of Yunmai 52. [Conclusion] Therefore, in extension and application of Yunmal 52 that is a high-quality high-yield multi-resistant new wheat variety, supply of fertilizer and water should be increased in tillering stage and jointing stage, to ensure its characteristics of high tilledng ability and large ear, as well as high 1 000-grain weight, and coordinated development of other yield-related traits is beneficial to im- provement of yield of Yunmai 52.展开更多
[Objective]The experiment aimed to study the effects of meteorological factors under different weather conditions on soil respiration. [ Method] The path analysis was used to analyze meteorological factors which influ...[Objective]The experiment aimed to study the effects of meteorological factors under different weather conditions on soil respiration. [ Method] The path analysis was used to analyze meteorological factors which influenced soil respiration of wheat field under different weather condition and at jointing stage. [ Result] In sunny day, the correlations between ground temperature at 5 cm, solar radiation, air relative humidity, air temperature and soil respiration were all at significant level while solar radiation and ground temperature at 5 cm were the major factors which influenced soil respiration. In cloudy day, solar radiation was a major factor which influenced soil respiration.[ Conclusion] The soil respiration and surplus path coefficient in sunny day were all higher than these in cloudy day, which demonstrated that except influenced by ground temperature, air temperature, solar radiation and air relative humidity, the soil respiration was also influenced by other factors especially biological factor.展开更多
The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that ...The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that since the implementation of the household contract management system in rural areas, the family farm has followed the track of gradual development, breakthrough development and normal standardization development. In order to promote the family farm to develop rapidly, orderly and healthily, work must be well done to land circulation, scale management, financial support, financial subsidy, cultivation of leading talents and professional farmers, and providing all-round services.展开更多
Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The r...Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.展开更多
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto...The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.展开更多
Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the perio...Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P 0.05).Only winter precipitation increased significantly(P 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.展开更多
Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New...Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New indica cultivars(53 in 2007 and 48 in 2008) were grown in Taoyuan,Yunnan province, to identify important components contributing to yield. Additionally, two standard indica rice cultivars with similar yield potentials, II You 107(a large-panicle type) and Xieyou 107(a heavy-panicle type), were planted in Taoyuan, Yunnan province and Nanjing,Jiangsu province, from 2006 to 2008 to evaluate the stability of yield and yield-related attributes.Growth duration(GD), leaf area index(LAI), panicles per m2(PN), and spikelets per m2(SM) were significantly and positively correlated with grain yield(GY) over all years. Sequential path analysis identified PN and panicle weight(PW) as important first-order traits that influenced grain yield. All direct effects were significant, as indicated by bootstrap analysis. Yield potential varied greatly across locations but not across years. Plant height(PH), days from heading to maturity(HM), and grain weight(GW) were stable traits that showed little variation across sites or years, whereas GD(mainly the pre-heading period, PHP) and PN varied significantly across locations. To achieve a yield of 15 t ha-1, a cultivar should have a PH of 110–125 cm, a long GD with HM of approximately 40 days, a PN of 300–400 m-2, and a GW of 29–31 mg.展开更多
Spring snowmelt peak flow (SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by ...Spring snowmelt peak flow (SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF. This study used path analysis with a selection of five factors - the antecedent precipitation index (API), spring precipitation (SP), winter precipitation as snowfall (WS), 〈0℃ temperature accumulation in winter ([ATNI), and average 〉0℃temperature accumulation in spring (AT) - to analyze their influences on the SSPF in the Kaidu River in Xinjiang, China. The results show that {ATN}, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of[ATN] on SSPF is indirect through WS and AT. The indirect influence of [ATN[ on SSPF through WS accounts for 69% of the total influence of [ATN] on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.展开更多
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wil...Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs.展开更多
Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particul...Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particulate matter pollution.In this paper,the influences of the main parameters on the droplet size,effective atomization range and sound pressure level(SPL)of a twin-fluid nozzle(TFN)are investigated,and in order to improve the atomization performance,a multi-objective synergetic optimization algorithm is presented.A multi-physics coupled acousticmechanics model based on the discrete phase model(DPM),large eddy simulation(LES)model,and Ffowcs Williams-Hawkings(FW-H)model is established,and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental comparison.Based on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results,the effects of the water flow on the characteristics of the atomization flow distribution were obtained.A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database,and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the TFN.The optimal parameters are as follows:A gas flow of 0.94 m^(3)/h,water flow of 0.0237 m^(3)/h,orifice diameter of the self-excited vibrating cavity(SVC)of 1.19 mm,SVC orifice depth of 0.53 mm,distance between SVC and the outlet of nozzle of 5.11 mm,and a nozzle outlet diameter of 3.15 mm.The droplet particle size in the atomization flow field was significantly reduced,the spray distance improved by 71.56%,and the SPL data at each corresponding measurement point decreased by an average of 38.96%.The conclusions of this study offer a references for future TFN research.展开更多
Unlike the shortest path problem that has only one optimal solution and can be solved in polynomial time, the muhi-objective shortest path problem ( MSPP ) has a set of pareto optimal solutions and cannot be solved ...Unlike the shortest path problem that has only one optimal solution and can be solved in polynomial time, the muhi-objective shortest path problem ( MSPP ) has a set of pareto optimal solutions and cannot be solved in polynomial time. The present algorithms focused mainly on how to obtain a precisely pareto optimal solution for MSPP resulting in a long time to obtain multiple pareto optimal solutions with them. In order to obtain a set of satisfied solutions for MSPP in reasonable time to meet the demand of a decision maker, a genetic algo- rithm MSPP-GA is presented to solve the MSPP with typically competing objectives, cost and time, in this pa- per. The encoding of the solution and the operators such as crossover, mutation and selection are developed. The algorithm introduced pareto domination tournament and sharing based selection operator, which can not only directly search the pareto optimal frontier but also maintain the diversity of populations in the process of evolutionary computation. Experimental results show that MSPP-GA can obtain most efficient solutions distributed all along the pareto frontier in less time than an exact algorithm. The algorithm proposed in this paper provides a new and effective method of how to obtain the set of pareto optimal solutions for other multiple objective optimization problems in a short time.展开更多
Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the ...Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.52208380 and 51979270)the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(Grant No.SKLGME021022).
文摘Real-time prediction of excavation-induced displacement of retaining pile during the deep excavation process is crucial for construction safety.This paper proposes a modified back analysis method with multi-objective optimization procedure,which enables a real-time prediction of horizontal displacement of retaining pile during construction.As opposed to the traditional stage-by-stage back analysis,time series monitoring data till the current excavation stage are utilized to form a multi-objective function.Then,the multi-objective particle swarm optimization (MOPSO) algorithm is applied for parameter identification.The optimized model parameters are immediately adopted to predict the excavation-induced pile deformation in the continuous construction stages.To achieve efficient parameter optimization and real-time prediction of system behavior,the back propagation neural network (BPNN) is established to substitute the finite element model,which is further implemented together with MOPSO for automatic operation.The proposed approach is applied in the Taihu tunnel excavation project,where the effectiveness of the method is demonstrated via the comparisons with the site monitoring data.The method is reliable with a prediction accuracy of more than 90%.Moreover,different optimization algorithms,including non-dominated sorting genetic algorithm (NSGA-II),Pareto Envelope-based Selection Algorithm II (PESA-II) and MOPSO,are compared,and their influences on the prediction accuracy at different excavation stages are studied.The results show that MOPSO has the best performance for high dimensional optimization task.
基金This work was supported by Guizhou Provincial Basic Research Program(Natural Science),Grant Number Qiankehejichu-ZK[2021]YB133Guizhou Provincial Scientific and Technological Program,Grant Number Qiankehehoubuzhu[2020]3001National Natural Science Foundation of China-Guizhou Provincial People’s Government Karst Science Research Centre(U1612442).
文摘The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.
文摘With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality development of the regional economy,industrial policies are increasingly receiving attention in terms of their role and impact.This article mainly conducts an in-depth analysis of the mechanism and impact path of industrial policies,exploring the role and impact of industrial policies in promoting high-quality regional economic development.Firstly,industrial policies play an important role in promoting high-quality regional economic development.Secondly,the impact path of industrial policies on the high-quality development of the regional economy mainly includes promoting industrial structure upgrading,promoting technological innovation,guiding resource allocation,and enhancing enterprise competitiveness.Therefore,it is necessary to increase research and practice on industrial policies,continuously optimize policy measures,and promote high-quality development of the regional economy.
基金Jiangsu Province Philosophy and Social Sciences General Project"Exploration of the Path for Cultivating Innovation and Entrepreneurship Ability of Employment-Oriented Applied Undergraduate Talents"。
文摘The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enriches course materials,integrates teacher resources,improves students’participation in innovation and entrepreneurship,and solves problems such as low student participation,lack of course resources,insufficient teacher resources,and single evaluation methods in traditional classrooms.Through various means such as exploring course resources,innovating management models,and strengthening team construction,the role of“one-stop”student communities in innovation and entrepreneurship education has been fully utilized,promoting the development of innovation and entrepreneurship education.
文摘The pressurizing pipeline of hot press resonates under the excitation load,which poses a serious hidden danger to the safety of the equipment and the operator.In order to increase the natural frequency of the pressurizing pipeline,modal analysis of the pressurizing pipeline is carried out to study the mechanism of pipeline vibration and common vibration reduction measures.A method of increasing the natural frequency of the pressurizing pipeline was analyzed.The influence of pipeline clamp assembly stiffness,pipeline clamp number and pipeline clamp installation position on the mode of the pressurizing pipeline is studied.Sensitivity analysis is carried out to study the influence of the various parameters on the mode of the pressurizing pipeline.Genetic algorithm based on Pareto optimality is introduced for multi-objective optimization of pressurizing pipeline.The optimization results show that the natural frequency of the pressurizing pipeline increases by 2.4%and the displacement response is reduced by 17.7%.
基金grants of the Guangdong Marine and Fishery Bureau(No.B02068)Guangdong Ocean University(No.E06031).
文摘120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated (P 〈 0.05). Total weight was significantly and positively correlated with shell weight (r = 0.8970), shell height (r = 0.6974), shell width (r = 0.6521) and shell length (r = 0.5486). Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits (shell length, shell width, shell height, shell weight and total wet weigh) of the F1 population could be improved by direct or indirect selection.
文摘Driven by the goal of“carbon neutrality,”the increase in use of renewable energy power systems will be inevitable in the future.Uncontrolled output power and random volatility make it difficult to balance power in real time during system operation.Therefore,energy storage is considered to be an effective way to ensure the real-time balance of system power.However,cost of energy storage is relatively expensive.As a solution,energy storage can be used to balance the system power in order to reduce system operating costs.Taking the high proportion of wind power systems as an example,the impact of the“supply side”low-carbon transformation on the economics and reliability of power system operation is explored.In order to solve the problem of power system operation configuration optimization under the background of“carbon neutrality,”this paper establishes a multi-objective programming model.
文摘In April of 2006, a base population of the noble scallop Chlamys nobilis was established by collecting parental breeders from the stocks in Wushi, Zhanjiang. In December of 2006, 200 individuals were randomly sampled from the base population and subjected for correlation and path coefficient analysis. It was found that there were statistically significant phenotypic correlations among the traits (P 〈 0.01). Total weight was significantly and positively correlated with the shell length (r = 0.934 3), shell height (r = 0.895 9), shell width (r = 0.899 1 ), muscle weight (r = 0.882 0) and shell weight (r = 0.937 9), respectively. Shell length, shell width, muscle weight, shell height and shell weight had positive and direct effects on the total weight, with values of 0.397 1, 0.321 9, 0.172 1, 0.089 6 and 0.066 9, respectively. Shell length, shell width and muscle weight had higher direct effects on the total weight than shell height and shell weight. A combined evaluation of correlation, direct effects and indirect effects showed that direct selection for shell length, shell width, muscle weight, shell height and shell weight would be effective to improving the total weight. It was concluded that these traits could be regarded as the selection criteria in breeding programs of the species.
基金Supported by National key R&D Projects(2016YFD0101603)National Planning Project Co-supported by Yunnan Province(2014GA016)Science&Technology Specific Project for Benefiting People in China(2014RA056)~~
文摘[Objective] This study was tween yield-related traits and yield of conducted to understand the relationship be- Yunmai 52 which is a high-quality high-yield multi-resistant new wheat variety, and make contribution of yield-related traits to the yield of Yunmai 52 clear. [Method] Wheat variety regional trial data in Yunnan Province in 2005-2007 were subjected to correlation analysis and path analysis in the paper. [Result] Correlationanalysis showed that the yield of Yunmai 52 was in- very significant positive correlation with spikelet number per ear, maximum tiller number and grains per ear (r=0.726^**, 0.717^** and 0.695^**, respectively), in signif- icant positive correlation with 1 000-grain weight (r=0.491^*), but in significant nega- tive correlation with sterile spikelet number per ear, and in non-significant correlation with basic seedlings, effective ears and percentage of ear bearing tillers. Partial correlation analysis showed that the yield of Yunmai 52 was in very significant posi- tive correlation with spikelet number per ear (r=0.711^**), significant positive correla- tion with 1 000-grain weight (r=0.641 =), but in non-significant correlation with other 6 traits. Path analysis showed that spikelet number per ear (P=-0.595), maximum tiller number (P=0.462) and t 000-grain weight (P=0.263) had more contribution to yield of Yunmai 52. [Conclusion] Therefore, in extension and application of Yunmal 52 that is a high-quality high-yield multi-resistant new wheat variety, supply of fertilizer and water should be increased in tillering stage and jointing stage, to ensure its characteristics of high tilledng ability and large ear, as well as high 1 000-grain weight, and coordinated development of other yield-related traits is beneficial to im- provement of yield of Yunmai 52.
基金Supported by the Scientific Research Foundation of Nanjing Universityof Information Science and Technology(80124)~~
文摘[Objective]The experiment aimed to study the effects of meteorological factors under different weather conditions on soil respiration. [ Method] The path analysis was used to analyze meteorological factors which influenced soil respiration of wheat field under different weather condition and at jointing stage. [ Result] In sunny day, the correlations between ground temperature at 5 cm, solar radiation, air relative humidity, air temperature and soil respiration were all at significant level while solar radiation and ground temperature at 5 cm were the major factors which influenced soil respiration. In cloudy day, solar radiation was a major factor which influenced soil respiration.[ Conclusion] The soil respiration and surplus path coefficient in sunny day were all higher than these in cloudy day, which demonstrated that except influenced by ground temperature, air temperature, solar radiation and air relative humidity, the soil respiration was also influenced by other factors especially biological factor.
基金Supported by the Social Science Funding Project of Hubei Province(201590)~~
文摘The Chinese family farm is the most important new micro subject in the construction and development of modern agriculture in China. The investigation and analysis of the actual situation of Hubei Province showed that since the implementation of the household contract management system in rural areas, the family farm has followed the track of gradual development, breakthrough development and normal standardization development. In order to promote the family farm to develop rapidly, orderly and healthily, work must be well done to land circulation, scale management, financial support, financial subsidy, cultivation of leading talents and professional farmers, and providing all-round services.
基金the National Natural Science Foundation of China(Grant No.52270154)the National Engineering Research Center for Bioenergy,Harbin Institute of Technology,China(Grant No.2021C001).
文摘Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.
基金This work was supported of National Natural Science Foundation of China Fund(No.52306033)State Key Laboratory of Engines Fund(No.SKLE-K2022-07)the Jiangxi Provincial Postgraduate Innovation Special Fund(No.YC2022-s513).
文摘The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.
基金supported by the National Natural Sciences Foundation of China (40871027)the Initial Project of State Key Basic R & D Program of China (2009CB426309)the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-YW-334)
文摘Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P 0.05).Only winter precipitation increased significantly(P 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.
基金supported by the National Key Technology R&D Program of China (2011BAD16B14, 2012BAD20B05, 2012BAD04B08, and 2013BAD20B05)
文摘Improvement of yield in rice(Oryza sativa L.) is vital for ensuring food security in China. Both rice breeders and growers need an improved understanding of the relationship between yield and yield-related traits. New indica cultivars(53 in 2007 and 48 in 2008) were grown in Taoyuan,Yunnan province, to identify important components contributing to yield. Additionally, two standard indica rice cultivars with similar yield potentials, II You 107(a large-panicle type) and Xieyou 107(a heavy-panicle type), were planted in Taoyuan, Yunnan province and Nanjing,Jiangsu province, from 2006 to 2008 to evaluate the stability of yield and yield-related attributes.Growth duration(GD), leaf area index(LAI), panicles per m2(PN), and spikelets per m2(SM) were significantly and positively correlated with grain yield(GY) over all years. Sequential path analysis identified PN and panicle weight(PW) as important first-order traits that influenced grain yield. All direct effects were significant, as indicated by bootstrap analysis. Yield potential varied greatly across locations but not across years. Plant height(PH), days from heading to maturity(HM), and grain weight(GW) were stable traits that showed little variation across sites or years, whereas GD(mainly the pre-heading period, PHP) and PN varied significantly across locations. To achieve a yield of 15 t ha-1, a cultivar should have a PH of 110–125 cm, a long GD with HM of approximately 40 days, a PN of 300–400 m-2, and a GW of 29–31 mg.
基金financially supported by the Project of State Key Basic R & D Program of China (973 Program, Grant No. 2010CB951002)the key deployment project of Chinese Academy of Sciences (Grant No. KZZD-EW-12-2)Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (Grant No. 2011T2Z40)
文摘Spring snowmelt peak flow (SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the SSPF. This study used path analysis with a selection of five factors - the antecedent precipitation index (API), spring precipitation (SP), winter precipitation as snowfall (WS), 〈0℃ temperature accumulation in winter ([ATNI), and average 〉0℃temperature accumulation in spring (AT) - to analyze their influences on the SSPF in the Kaidu River in Xinjiang, China. The results show that {ATN}, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of[ATN] on SSPF is indirect through WS and AT. The indirect influence of [ATN[ on SSPF through WS accounts for 69% of the total influence of [ATN] on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.
基金Supported by the Modern Agro-Industry Technology Research System(No.CARS-48)
文摘Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs.
基金Supported by National Natural Science Foundation of China (Grant No.U21A20122)Zhejiang Provincial Natural Science Foundation of China (Grant No.LY22E050012)+2 种基金China Postdoctoral Science Foundation (Grant Nos.2023T160580,2023M743102)Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems of China (Grant No.GZKF-202225)Students in Zhejiang Province Science and Technology Innovation Plan of China (Grant No.2023R403073)。
文摘Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particulate matter pollution.In this paper,the influences of the main parameters on the droplet size,effective atomization range and sound pressure level(SPL)of a twin-fluid nozzle(TFN)are investigated,and in order to improve the atomization performance,a multi-objective synergetic optimization algorithm is presented.A multi-physics coupled acousticmechanics model based on the discrete phase model(DPM),large eddy simulation(LES)model,and Ffowcs Williams-Hawkings(FW-H)model is established,and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental comparison.Based on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results,the effects of the water flow on the characteristics of the atomization flow distribution were obtained.A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database,and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the TFN.The optimal parameters are as follows:A gas flow of 0.94 m^(3)/h,water flow of 0.0237 m^(3)/h,orifice diameter of the self-excited vibrating cavity(SVC)of 1.19 mm,SVC orifice depth of 0.53 mm,distance between SVC and the outlet of nozzle of 5.11 mm,and a nozzle outlet diameter of 3.15 mm.The droplet particle size in the atomization flow field was significantly reduced,the spray distance improved by 71.56%,and the SPL data at each corresponding measurement point decreased by an average of 38.96%.The conclusions of this study offer a references for future TFN research.
文摘Unlike the shortest path problem that has only one optimal solution and can be solved in polynomial time, the muhi-objective shortest path problem ( MSPP ) has a set of pareto optimal solutions and cannot be solved in polynomial time. The present algorithms focused mainly on how to obtain a precisely pareto optimal solution for MSPP resulting in a long time to obtain multiple pareto optimal solutions with them. In order to obtain a set of satisfied solutions for MSPP in reasonable time to meet the demand of a decision maker, a genetic algo- rithm MSPP-GA is presented to solve the MSPP with typically competing objectives, cost and time, in this pa- per. The encoding of the solution and the operators such as crossover, mutation and selection are developed. The algorithm introduced pareto domination tournament and sharing based selection operator, which can not only directly search the pareto optimal frontier but also maintain the diversity of populations in the process of evolutionary computation. Experimental results show that MSPP-GA can obtain most efficient solutions distributed all along the pareto frontier in less time than an exact algorithm. The algorithm proposed in this paper provides a new and effective method of how to obtain the set of pareto optimal solutions for other multiple objective optimization problems in a short time.
基金Supported by Platform Construction for Germplasm Resources of China Tobacco (2007, 152)
文摘Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related.