Sponge city(SPC)is proposed to solve the issues such as the degradation of urban water ecosystem environment,imbalanced water resource allocation,urban water logging,and water contamination.The PPP(Public Private Part...Sponge city(SPC)is proposed to solve the issues such as the degradation of urban water ecosystem environment,imbalanced water resource allocation,urban water logging,and water contamination.The PPP(Public Private Partnership)model is combined to release the government pressure of SPC project construction.The development of the SPC-PPP model makes significant contributions to the sustainable development and the enhancement of urban resilience against water-related disasters.However,there is no scientific performance evaluation system on its operation period has been conducted.Therefore,the SPC-PPP Evaluation model aims to objectively and reasonably assess project effectiveness,promote its development and refine the evaluation framework.This paper has set up the MEE model for performance evaluation,with improved Matter-Element Extension method to assign values to the evaluation indices.The research results show that:(1)The MEE model is more accurate in the performance evaluation and its effectiveness is reflected in its ability to capture the correlation among different indices in the same membership,rather than merely focusing on individual indices.(2)The proposed approach provided a new aspect for performance evaluation,improving the accuracy of evaluation and promoting the development of SPC-PPP project.展开更多
Taking shallow groundwater in Jinjiang City,Fujian Province for example,it was found that the classical element-matter analysis shows deficiency in calculation of correlation function,so the improved matter-element me...Taking shallow groundwater in Jinjiang City,Fujian Province for example,it was found that the classical element-matter analysis shows deficiency in calculation of correlation function,so the improved matter-element method was applied for the comprehensive assessment of shallow groundwater in Jinjiang City,and the spatial distribution was shown in maps.The assessment results demonstrated that ground water quality of most regions in the study area belonged to Grade I and II,thus the overall quality of shallow groundwater was good.The groundwater of Grade IV and V(relatively poor and extremely poor) was mainly distributed in Dongshi Town,Chendi Town,Zimao Town,and Shenhu Town,major exceeding-standard factors that influence shallow groundwater quality in the local area included TDS,Mn^(2+),NO_3,NO_2,NH_4^+ and Cl^-,which mainly owed to invasion of seawater,original geological conditions,industrial and agricultural discharge,and human life.展开更多
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th...For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.展开更多
As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great chang...As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great changes. Research on changes in Zhuhai’s land ecological security is of great significance. Using relevant data from 2007-2012, this study established a land ecological security assessment system based on the PSR conceptual framework model. The system contained 18 indicators from 3 aspects according to the concrete features of Zhuhai. Then we used the matterelement analysis and the improved entropy weight to analyze and evaluate the land ecological security of Zhuhai. The results showed that: from 2007 to 2012, the levels of the land ecological security of Zhuhai were “secure”, and the value increased year by year;as the land ecological security response value increased, Zhuhai was capable of solving land ecosystem problems. However, it should be noted that the structure of land ecosystem in Zhuhai has not formed and that rapid expansion of construction land has caused the shortage of cultivated land and other issues. Measures should be taken to control the construction area, improve land intensive utilization and improve the land ecological security.展开更多
The pushover analysis （POA） procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis （MPA） procedur...The pushover analysis （POA） procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis （MPA） procedure was proposed by Chopra et al. （2001）. However, invariable lateral force distributions are still adopted in the MPA. In this paper, an improved MPA procedure is presented to estimate the seismic demands of structures, considering the redistribution of inertia forces after the structure yields. This improved procedure is verified with numerical examples of 5-, 9- and 22-story buildings. It is concluded that the improved MPA procedure is more accurate than either the POA procedure or MPA procedure. In addition, the proposed procedure avoids a large computational effort by adopting a two-phase lateral force distribution..展开更多
The main features and connotation of the tolerance human resource management based on strategy are analyzed and summarized. The theory and method of systematic engineering is used to build the evaluation index systems...The main features and connotation of the tolerance human resource management based on strategy are analyzed and summarized. The theory and method of systematic engineering is used to build the evaluation index systems for the tolerance human resource management. On the basis of it, by using the theory of matter-element analysis, the matter-element models are formulated for the evaluation of the tolerance human resource management. Regarding annual tolerance human resource management as the object of matter-dement, the tolerance human resource ：management for two years are analyzed and evaluated through using the matter. element models proposed. A ease study is carried out and the satisfactory results are obtained. A new scientific methed is provided for the evaluation of human resource management based on strategy.展开更多
Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude flights.However,a turbocharger significantly increases the complexity ...Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude flights.However,a turbocharger significantly increases the complexity of a power system,and its considerably complex matching relation with the engine results in a coupling of failure modes.Conventional analytical methods are hard to identify failure-inducing factors.Consequently,safety issues are becoming increasingly prominent.This study focuses on methods for identifying failure-inducing factors.A whole-machine system model is established and validated through experimentation.The response surface method is employed to further abstract the system simulation model to a surrogate model(average error:~3%)in order to reduce the computational cost while ensuring accuracy.On this basis,an improved Correspondence Analysis(CA)-Polar Angle(PA)-based Classification(PAC)is proposed to identify the key factors affecting the failure mode of turbochargers.This identification method is based on the row profile coordinates G varying with the numerical deviations of the key factors,and is capable of effectively identifying the key factors affecting the failure.In a validation example,this method identifies the diameter of the exhaust valve(e_(2))as the primary factor affecting the safety margin for each work boundary.展开更多
With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In th...With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation.展开更多
Men and women farmer participation and choice of variety could guide breeding and drive the adoption of different haricot bean varieties. Thus, understanding how gender influences participation and choice of bean cult...Men and women farmer participation and choice of variety could guide breeding and drive the adoption of different haricot bean varieties. Thus, understanding how gender influences participation and choice of bean cultivation and marketing is fundamental. The study sought to analyse how socio-cultural norms determine women and men, participation and choice of variety for cultivation and sale in Cameroon’s West region. A mixed-method was used in collecting data from men and women farmers in six subdivisions in the West region of Cameroon in 2019. Result reveals that women provide most of the labour on haricot bean production than men, who are more involved in selling to national and regional markets. Participation and role were driven by socio-cultural norms of what is expected of men and women in a society where women provide food and men income for household upkeep. Women preferred varieties that were less labour intensive and food taste for household consumption while men went for labour intensive as long as they were market-oriented and high yielding. Thus, breeders should develop varieties that are mostly preferred by women, which meet the market and household demand.展开更多
A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which i...A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which influence the controller workload were determined. By establishing the classical field and node field of the controller workload, the correlation function of the controller workload grade was obtained; then the correlation degree and estimated grade of controller workload were given. A case study verifies the feasibility of the proposed evaluation method.展开更多
Wireless communication is easily disturbed by unfortunate factors which drive the wireless environment unstable and complicated. Therefore, it is essential to consider these factors in stability analysis of the wirele...Wireless communication is easily disturbed by unfortunate factors which drive the wireless environment unstable and complicated. Therefore, it is essential to consider these factors in stability analysis of the wireless network. However, wireless channel characteristics and packets collisions are neglected in the classical fluid model. A wireless TCP fluid model （WTFM） for stability analysis of wireless network is proposed based on cross layers, which not only makes the congestion control based on random early detection （RED） available for wireless network, but also provides a more accurate model to analyze the stability of wireless system theoretically. In the proposed model, active queue management, abnormality of wireless channels and packets collisions are taken into consideration. The comparisons between evaluating results from the WTFM and the practical performance from NS2 simulations validate the accuracy of the proposed WTFM in the perspectives of delay, dropping probability, throughput, sliding window size and queue length. A set of comparisons among the proposed WTFM, the classical fluid model and the convex optimization model are conducted. The results demonstrate that the proposed WTFM model performs better than other schemes in comprehensive aspects on capturing the characteristic of the wireless network and computing complexity.展开更多
The Francis turbine governing system models in PSD-BPA can’t precisely reflect the actual characteristics. Endeavor was done in this paper to solve the problem. An improved model of actuating mechanism was developed,...The Francis turbine governing system models in PSD-BPA can’t precisely reflect the actual characteristics. Endeavor was done in this paper to solve the problem. An improved model of actuating mechanism was developed, which could reflect the step closing characteristic of hydro guide vanes. The effect of the inflection point value of actuating mechanism on load rejection was analyzed based on simulation. The non-linear Francis turbine model with power versus gate position module was researched in this paper. Based on field test, comparisons of simulation results with measured data were presented. The analysis demonstrates that the improved models of Francis turbine and governor proposed in this paper are more realistic than the models of BPA, and can be applied in power system simulation analysis better.展开更多
The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and al...The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational.展开更多
The objective of this study was to determine the influence of production and consumption characteristics of improved sorghum varieties on farmers＇ adoption decisions. Thirty-four farmers and 231 consumers evaluated f...The objective of this study was to determine the influence of production and consumption characteristics of improved sorghum varieties on farmers＇ adoption decisions. Thirty-four farmers and 231 consumers evaluated five sorghum varieties to determine their preferences. The perceptions of the farmers and consumers were summarized and presented to 100 sorghum farmers to help them choose the best varieties, based on results obtained earlier. Ordered probit models were used to predict their adoption decisions. Results indicated that when adoption is predicted on production characteristics alone the adoption rate was lower than when prediction incorporated both production and consumption characteristics of the sorghum varieties. Therefore, when disseminating new technologies farmers need to be informed about the production as well as the consumption characteristics of the new technologies. The outcomes of this study imply that involving producers and consumers in the generation of new agricultural technologies would potentially increase their adoption rates when they are disseminated. Thus a subsector analytical approach is recommended.展开更多
This paper expounds the concept of HVAC construction,specifically analyzes the current situation of HVAC construction in construction engineering,and focuses on the key and difficult points in HVAC construction.In ord...This paper expounds the concept of HVAC construction,specifically analyzes the current situation of HVAC construction in construction engineering,and focuses on the key and difficult points in HVAC construction.In order to provide an effective reference for improving the quality of HVAC construction in the current construction engineering,some suggestions are put forward for improvement of relevant technologies involved in key and difficult points.展开更多
For effectively improving the overall performance of fire truck frame structure,and solving the complexity of previous methods in the frame optimization design process,the traditional grey relational grade ranking nee...For effectively improving the overall performance of fire truck frame structure,and solving the complexity of previous methods in the frame optimization design process,the traditional grey relational grade ranking needs to be improved.First,the first-order modal test was conducted to verify the validity of the initial frame model.Then,based on this model,a high-strength steel frame was designed to reduce deformation,maximum stress,and frame mass,and increase the fatigue life and the frequencies of the first bending modal and first torsional modal.Sixty groups of sample points were generated through Hammersley method.Subsequently,improved grey relational analysis with principal component analysis was proposed to realize the optimal design of the frame structure.Finally,the optimal combination of design parameters for the frame was obtained using the proposed method.Meanwhile,the optimized frame structure is found by comparing the models before and after optimization,and the mass is reduced by 14.8%.Moreover,the computational cost can be reduced by 135%when the proposed method is compared with the previous algorithm.Therefore,the proposed method can effectively improve the performance of the frame and improve the computational efficiency.展开更多
The transient impulse features caused by rolling bearing faults are often present in the resonance frequency band which is closely related to the dynamic characteristics of the machine structure.Informative frequency ...The transient impulse features caused by rolling bearing faults are often present in the resonance frequency band which is closely related to the dynamic characteristics of the machine structure.Informative frequency band identification is a crucial prerequisite for envelope analysis and thereby accurate fault diagnosis of rolling bearings.In this paper,based on the ratio of quasi-arithmetic means and Gini index,improved Gini indices(IGIs)are proposed to quantify the transient impulse features of a signal,and their effectiveness and advantages in sparse quantification are confirmed by simulation analysis and comparisons with traditional sparsity measures.Furthermore,an IGI-based envelope analysis method named IGIgram is developed for fault diagnosis of rolling bearings.In the new method,an IGI-based indicator is constructed to evaluate the impulsiveness and cyclostationarity of the narrow-band filtered signal simultaneously,and then a frequency band with abundant fault information is adaptively determined for extracting bearing fault features.The performance of the IGIgram method is verified on the simulation signal and railway bearing experimental signals and compared with typical sparsity measures-based envelope analysis methods and log-cycligram.The results demonstrate that the proposed IGIs are efficient in quantifying bearing fault-induced transient features and the IGIgram method with appropriate power exponent can effectively achieve the diagnostics of different axle-box bearing faults.展开更多
The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.Howev...The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.However,most scholars currently focus on modifying methods to enhance model accuracy,while overlooking the extent to which input parameters influence accuracy.To address this issue,in this study,a prediction model for the endpoint carbon content in the converter was developed using factor analysis(FA)and support vector machine(SVM)optimized by improved particle swarm optimization(IPSO).Analysis of the factors influencing the endpoint carbon content during the converter smelting process led to the identification of 21 input parameters.Subsequently,FA was used to reduce the dimensionality of the data and applied to the prediction model.The results demonstrate that the performance of the FA-IPSO-SVM model surpasses several existing methods,such as twin support vector regression and support vector machine.The model achieves hit rates of 89.59%,96.21%,and 98.74%within error ranges of±0.01%,±0.015%,and±0.02%,respectively.Finally,based on the prediction results obtained by sequentially removing input parameters,the parameters were classified into high influence(5%-7%),medium influence(2%-5%),and low influence(0-2%)categories according to their varying degrees of impact on prediction accuracy.This classi-fication provides a reference for selecting input parameters in future prediction models for endpoint carbon content.展开更多
Software projects influenced by many human factors generate various risks. In order to develop highly quality software, it is important to respond to these risks reasonably and promptly. In addition, it is not easy fo...Software projects influenced by many human factors generate various risks. In order to develop highly quality software, it is important to respond to these risks reasonably and promptly. In addition, it is not easy for project managers to deal with these risks completely. Therefore, it is essential to manage the process quality by promoting activities of process monitoring and design quality assessment. In this paper, we discuss statistical data analysis for actual project management activities in process monitoring and design quality assessment, and analyze the effects for these software process improvement quantitatively by applying the methods of multivariate analysis. Then, we show how process factors affect the management measures of QCD (Quality, Cost, Delivery) by applying the multiple regression analyses to observed process monitoring data. Further, we quantitatively evaluate the effect by performing design quality assessment based on the principal component analysis and the factor analysis. As a result of analysis, we show that the design quality assessment activities are so effective for software process improvement. Further, based on the result of quantitative project assessment, we discuss the usefulness of process monitoring progress assessment by using a software reliability growth model. This result may enable us to give a useful quantitative measure of product release determination.展开更多
The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
基金supported by the Open Fund of Hubei Key Laboratory of Construction Management in Hydropower Engineering(Grant No.2016KSD04)the Open Fund of Engineering Research Center of Eco-environment in Three Gorges Reservoir Region,Ministry of Education(Grant No.KF2016-11).
文摘Sponge city(SPC)is proposed to solve the issues such as the degradation of urban water ecosystem environment,imbalanced water resource allocation,urban water logging,and water contamination.The PPP(Public Private Partnership)model is combined to release the government pressure of SPC project construction.The development of the SPC-PPP model makes significant contributions to the sustainable development and the enhancement of urban resilience against water-related disasters.However,there is no scientific performance evaluation system on its operation period has been conducted.Therefore,the SPC-PPP Evaluation model aims to objectively and reasonably assess project effectiveness,promote its development and refine the evaluation framework.This paper has set up the MEE model for performance evaluation,with improved Matter-Element Extension method to assign values to the evaluation indices.The research results show that:(1)The MEE model is more accurate in the performance evaluation and its effectiveness is reflected in its ability to capture the correlation among different indices in the same membership,rather than merely focusing on individual indices.(2)The proposed approach provided a new aspect for performance evaluation,improving the accuracy of evaluation and promoting the development of SPC-PPP project.
基金Sponsored by Innovative Experimental Program in Fujian Province(201610399051)Program of Quanzhou Bureau of Science and Technology(20152139)
文摘Taking shallow groundwater in Jinjiang City,Fujian Province for example,it was found that the classical element-matter analysis shows deficiency in calculation of correlation function,so the improved matter-element method was applied for the comprehensive assessment of shallow groundwater in Jinjiang City,and the spatial distribution was shown in maps.The assessment results demonstrated that ground water quality of most regions in the study area belonged to Grade I and II,thus the overall quality of shallow groundwater was good.The groundwater of Grade IV and V(relatively poor and extremely poor) was mainly distributed in Dongshi Town,Chendi Town,Zimao Town,and Shenhu Town,major exceeding-standard factors that influence shallow groundwater quality in the local area included TDS,Mn^(2+),NO_3,NO_2,NH_4^+ and Cl^-,which mainly owed to invasion of seawater,original geological conditions,industrial and agricultural discharge,and human life.
基金supported by the National Natural Science Foundation of China (No. 41071322, 71031001)
文摘For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment.
文摘As one of the Special Economic Zones since the reform and opening up, Zhuhai has developed during the past 30 years. Its economic development, industrial structure and ecological environment have undergone great changes. Research on changes in Zhuhai’s land ecological security is of great significance. Using relevant data from 2007-2012, this study established a land ecological security assessment system based on the PSR conceptual framework model. The system contained 18 indicators from 3 aspects according to the concrete features of Zhuhai. Then we used the matterelement analysis and the improved entropy weight to analyze and evaluate the land ecological security of Zhuhai. The results showed that: from 2007 to 2012, the levels of the land ecological security of Zhuhai were “secure”, and the value increased year by year;as the land ecological security response value increased, Zhuhai was capable of solving land ecosystem problems. However, it should be noted that the structure of land ecosystem in Zhuhai has not formed and that rapid expansion of construction land has caused the shortage of cultivated land and other issues. Measures should be taken to control the construction area, improve land intensive utilization and improve the land ecological security.
基金Supported by: National Natural Science Foundation of China Under Grant No.50608024 and No.50538050 Opening Laboratory of Earthquake Engineering and Engineering Vibration Foundation Under Grant No.2007001
文摘The pushover analysis （POA） procedure is difficult to apply to high-rise buildings, as it cannot account for the contributions of higher modes. To overcome this limitation, a modal pushover analysis （MPA） procedure was proposed by Chopra et al. （2001）. However, invariable lateral force distributions are still adopted in the MPA. In this paper, an improved MPA procedure is presented to estimate the seismic demands of structures, considering the redistribution of inertia forces after the structure yields. This improved procedure is verified with numerical examples of 5-, 9- and 22-story buildings. It is concluded that the improved MPA procedure is more accurate than either the POA procedure or MPA procedure. In addition, the proposed procedure avoids a large computational effort by adopting a two-phase lateral force distribution..
文摘The main features and connotation of the tolerance human resource management based on strategy are analyzed and summarized. The theory and method of systematic engineering is used to build the evaluation index systems for the tolerance human resource management. On the basis of it, by using the theory of matter-element analysis, the matter-element models are formulated for the evaluation of the tolerance human resource management. Regarding annual tolerance human resource management as the object of matter-dement, the tolerance human resource ：management for two years are analyzed and evaluated through using the matter. element models proposed. A ease study is carried out and the satisfactory results are obtained. A new scientific methed is provided for the evaluation of human resource management based on strategy.
基金supported by the Innovation Team of Complex System Safety and Airworthiness of Aeroengine from the Co-Innovation Center for Advanced Aeroengine of Chinafunded by the National Natural Science Foundation of China and the Civil Aviation Administration of China(No.U1833109)。
文摘Turbocharging is an efficient approach for addressing power reduction and oil consumption increase in aviation piston engines during high-altitude flights.However,a turbocharger significantly increases the complexity of a power system,and its considerably complex matching relation with the engine results in a coupling of failure modes.Conventional analytical methods are hard to identify failure-inducing factors.Consequently,safety issues are becoming increasingly prominent.This study focuses on methods for identifying failure-inducing factors.A whole-machine system model is established and validated through experimentation.The response surface method is employed to further abstract the system simulation model to a surrogate model(average error:~3%)in order to reduce the computational cost while ensuring accuracy.On this basis,an improved Correspondence Analysis(CA)-Polar Angle(PA)-based Classification(PAC)is proposed to identify the key factors affecting the failure mode of turbochargers.This identification method is based on the row profile coordinates G varying with the numerical deviations of the key factors,and is capable of effectively identifying the key factors affecting the failure.In a validation example,this method identifies the diameter of the exhaust valve(e_(2))as the primary factor affecting the safety margin for each work boundary.
文摘With the increasing variety of application software of meteorological satellite ground system, how to provide reasonable hardware resources and improve the efficiency of software is paid more and more attention. In this paper, a set of software classification method based on software operating characteristics is proposed. The method uses software run-time resource consumption to describe the software running characteristics. Firstly, principal component analysis (PCA) is used to reduce the dimension of software running feature data and to interpret software characteristic information. Then the modified K-means algorithm was used to classify the meteorological data processing software. Finally, it combined with the results of principal component analysis to explain the significance of various types of integrated software operating characteristics. And it is used as the basis for optimizing the allocation of software hardware resources and improving the efficiency of software operation.
文摘Men and women farmer participation and choice of variety could guide breeding and drive the adoption of different haricot bean varieties. Thus, understanding how gender influences participation and choice of bean cultivation and marketing is fundamental. The study sought to analyse how socio-cultural norms determine women and men, participation and choice of variety for cultivation and sale in Cameroon’s West region. A mixed-method was used in collecting data from men and women farmers in six subdivisions in the West region of Cameroon in 2019. Result reveals that women provide most of the labour on haricot bean production than men, who are more involved in selling to national and regional markets. Participation and role were driven by socio-cultural norms of what is expected of men and women in a society where women provide food and men income for household upkeep. Women preferred varieties that were less labour intensive and food taste for household consumption while men went for labour intensive as long as they were market-oriented and high yielding. Thus, breeders should develop varieties that are mostly preferred by women, which meet the market and household demand.
基金The National Natural Science Foundation of China (60742117)
文摘A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which influence the controller workload were determined. By establishing the classical field and node field of the controller workload, the correlation function of the controller workload grade was obtained; then the correlation degree and estimated grade of controller workload were given. A case study verifies the feasibility of the proposed evaluation method.
基金supported by the National Natural Science Foundation of China(61106022)the Beijing Natural Science Foundation(4143066)
文摘Wireless communication is easily disturbed by unfortunate factors which drive the wireless environment unstable and complicated. Therefore, it is essential to consider these factors in stability analysis of the wireless network. However, wireless channel characteristics and packets collisions are neglected in the classical fluid model. A wireless TCP fluid model （WTFM） for stability analysis of wireless network is proposed based on cross layers, which not only makes the congestion control based on random early detection （RED） available for wireless network, but also provides a more accurate model to analyze the stability of wireless system theoretically. In the proposed model, active queue management, abnormality of wireless channels and packets collisions are taken into consideration. The comparisons between evaluating results from the WTFM and the practical performance from NS2 simulations validate the accuracy of the proposed WTFM in the perspectives of delay, dropping probability, throughput, sliding window size and queue length. A set of comparisons among the proposed WTFM, the classical fluid model and the convex optimization model are conducted. The results demonstrate that the proposed WTFM model performs better than other schemes in comprehensive aspects on capturing the characteristic of the wireless network and computing complexity.
文摘The Francis turbine governing system models in PSD-BPA can’t precisely reflect the actual characteristics. Endeavor was done in this paper to solve the problem. An improved model of actuating mechanism was developed, which could reflect the step closing characteristic of hydro guide vanes. The effect of the inflection point value of actuating mechanism on load rejection was analyzed based on simulation. The non-linear Francis turbine model with power versus gate position module was researched in this paper. Based on field test, comparisons of simulation results with measured data were presented. The analysis demonstrates that the improved models of Francis turbine and governor proposed in this paper are more realistic than the models of BPA, and can be applied in power system simulation analysis better.
文摘The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational.
文摘The objective of this study was to determine the influence of production and consumption characteristics of improved sorghum varieties on farmers＇ adoption decisions. Thirty-four farmers and 231 consumers evaluated five sorghum varieties to determine their preferences. The perceptions of the farmers and consumers were summarized and presented to 100 sorghum farmers to help them choose the best varieties, based on results obtained earlier. Ordered probit models were used to predict their adoption decisions. Results indicated that when adoption is predicted on production characteristics alone the adoption rate was lower than when prediction incorporated both production and consumption characteristics of the sorghum varieties. Therefore, when disseminating new technologies farmers need to be informed about the production as well as the consumption characteristics of the new technologies. The outcomes of this study imply that involving producers and consumers in the generation of new agricultural technologies would potentially increase their adoption rates when they are disseminated. Thus a subsector analytical approach is recommended.
文摘This paper expounds the concept of HVAC construction,specifically analyzes the current situation of HVAC construction in construction engineering,and focuses on the key and difficult points in HVAC construction.In order to provide an effective reference for improving the quality of HVAC construction in the current construction engineering,some suggestions are put forward for improvement of relevant technologies involved in key and difficult points.
基金the National Natural Science Foundation of China(No.51975244)。
文摘For effectively improving the overall performance of fire truck frame structure,and solving the complexity of previous methods in the frame optimization design process,the traditional grey relational grade ranking needs to be improved.First,the first-order modal test was conducted to verify the validity of the initial frame model.Then,based on this model,a high-strength steel frame was designed to reduce deformation,maximum stress,and frame mass,and increase the fatigue life and the frequencies of the first bending modal and first torsional modal.Sixty groups of sample points were generated through Hammersley method.Subsequently,improved grey relational analysis with principal component analysis was proposed to realize the optimal design of the frame structure.Finally,the optimal combination of design parameters for the frame was obtained using the proposed method.Meanwhile,the optimized frame structure is found by comparing the models before and after optimization,and the mass is reduced by 14.8%.Moreover,the computational cost can be reduced by 135%when the proposed method is compared with the previous algorithm.Therefore,the proposed method can effectively improve the performance of the frame and improve the computational efficiency.
基金supported by the National Key Research and Development Program of China (Grant No.2019YFB1405401)the National Natural Science Foundation of China (Grant No.P110520G02004)the China Scholarship Council (Grant No.202107000033),which are highly appreciated by the authors。
文摘The transient impulse features caused by rolling bearing faults are often present in the resonance frequency band which is closely related to the dynamic characteristics of the machine structure.Informative frequency band identification is a crucial prerequisite for envelope analysis and thereby accurate fault diagnosis of rolling bearings.In this paper,based on the ratio of quasi-arithmetic means and Gini index,improved Gini indices(IGIs)are proposed to quantify the transient impulse features of a signal,and their effectiveness and advantages in sparse quantification are confirmed by simulation analysis and comparisons with traditional sparsity measures.Furthermore,an IGI-based envelope analysis method named IGIgram is developed for fault diagnosis of rolling bearings.In the new method,an IGI-based indicator is constructed to evaluate the impulsiveness and cyclostationarity of the narrow-band filtered signal simultaneously,and then a frequency band with abundant fault information is adaptively determined for extracting bearing fault features.The performance of the IGIgram method is verified on the simulation signal and railway bearing experimental signals and compared with typical sparsity measures-based envelope analysis methods and log-cycligram.The results demonstrate that the proposed IGIs are efficient in quantifying bearing fault-induced transient features and the IGIgram method with appropriate power exponent can effectively achieve the diagnostics of different axle-box bearing faults.
基金financially supported by the National Natural Science Foundation of China(No.52174297).
文摘The endpoint carbon content in the converter is critical for the quality of steel products,and accurately predicting this parameter is an effective way to reduce alloy consumption and improve smelting efficiency.However,most scholars currently focus on modifying methods to enhance model accuracy,while overlooking the extent to which input parameters influence accuracy.To address this issue,in this study,a prediction model for the endpoint carbon content in the converter was developed using factor analysis(FA)and support vector machine(SVM)optimized by improved particle swarm optimization(IPSO).Analysis of the factors influencing the endpoint carbon content during the converter smelting process led to the identification of 21 input parameters.Subsequently,FA was used to reduce the dimensionality of the data and applied to the prediction model.The results demonstrate that the performance of the FA-IPSO-SVM model surpasses several existing methods,such as twin support vector regression and support vector machine.The model achieves hit rates of 89.59%,96.21%,and 98.74%within error ranges of±0.01%,±0.015%,and±0.02%,respectively.Finally,based on the prediction results obtained by sequentially removing input parameters,the parameters were classified into high influence(5%-7%),medium influence(2%-5%),and low influence(0-2%)categories according to their varying degrees of impact on prediction accuracy.This classi-fication provides a reference for selecting input parameters in future prediction models for endpoint carbon content.
文摘Software projects influenced by many human factors generate various risks. In order to develop highly quality software, it is important to respond to these risks reasonably and promptly. In addition, it is not easy for project managers to deal with these risks completely. Therefore, it is essential to manage the process quality by promoting activities of process monitoring and design quality assessment. In this paper, we discuss statistical data analysis for actual project management activities in process monitoring and design quality assessment, and analyze the effects for these software process improvement quantitatively by applying the methods of multivariate analysis. Then, we show how process factors affect the management measures of QCD (Quality, Cost, Delivery) by applying the multiple regression analyses to observed process monitoring data. Further, we quantitatively evaluate the effect by performing design quality assessment based on the principal component analysis and the factor analysis. As a result of analysis, we show that the design quality assessment activities are so effective for software process improvement. Further, based on the result of quantitative project assessment, we discuss the usefulness of process monitoring progress assessment by using a software reliability growth model. This result may enable us to give a useful quantitative measure of product release determination.
文摘The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of
