BACKGROUND Efficiently detecting Parkinson's disease(PD)with dementia(PDD)as soon as possible is an important issue in geriatric medicine.AIM To develop a model for predicting PDD based on various neuropsychologic...BACKGROUND Efficiently detecting Parkinson's disease(PD)with dementia(PDD)as soon as possible is an important issue in geriatric medicine.AIM To develop a model for predicting PDD based on various neuropsychological tests using data from a nationwide survey conducted by the Korean Centers for Disease Control and Prevention and to present baseline data for the early detection of PDD.METHODS This study comprised 289 patients who were 60 years or older with PD[110 with PDD and 179 Parkinson's Disease-Mild Cognitive Impairment(PD-MCI)].Regression with optimal scaling(ROS)was used to identify independent relationships between the neuropsychological test results and PDD.RESULTS In the ROS analysis,Korean version of mini mental state ex-amination(MMSE)(KOREAN version of MMSE)(b=-0.52,SE=0.16)and Hoehn and Yahr staging(b=0.44,SE=0.19)were significantly effective models for distinguishing PDD from PD-MCI(P<0.05),even after adjusting for all of the Parkinson's motor symptom and neuropsychological test results.The optimal number of categories(scaling factors)for KOREAN version of MMSE and Hoehn and Yahr Scale was 10 and 7,respectively.CONCLUSION The results of this study suggest that among the various neuropsychological tests conducted,the optimal classification scores for KOREAN version of MMSE and Hoehn and Yahr Scale could be utilized as an effective screening test for the early discrimination of PDD from PD-MCI.展开更多
The larger the difference between the willingness scale of tobacco family farmers and the optimal scale of efficiency,the greater the degree of irrationality,and the higher the decision making risk.With the aid of DEA...The larger the difference between the willingness scale of tobacco family farmers and the optimal scale of efficiency,the greater the degree of irrationality,and the higher the decision making risk.With the aid of DEA model,this study calculated the optimal scale of efficiency of Guiyang tobacco family farms.Using the ratio of willingness scale and efficiency optimal scale,it measured the degree of irrationality of family farmers.In addition,with the help of multiple linear regression model,it explained the irrational decision making mechanism of family farmers.Finally,it made a portrait of farmers who tend to make irrational decisions,to find specific farmers and guide them in their production and operation,reduce the risk of planting scale decision making and stabilize the sustainable development of the tobacco industry.展开更多
Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a ...Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance.展开更多
The long-term dynamic evolution and underlying mechanisms of coastal landscape pattern stability,driven by strong anthropogenic interference and consequently climate change,are topics of major interest in national and...The long-term dynamic evolution and underlying mechanisms of coastal landscape pattern stability,driven by strong anthropogenic interference and consequently climate change,are topics of major interest in national and international scientific research.Guangdong Province,located in southeastern China,has been undergoing rapid urbanization over several decades.In this study,we quantitatively determined the scale threshold characteristics of coastal landscape pattern stability in Guangdong Province,from the dual perspective of spatial heterogeneity and spatial autocorrelation.An analysis of the spatiotemporal evolution of the coastal landscape was conducted after the optical scale was determined.Then,we applied the geodetector statistical method to quantitatively explore the mechanisms underlying coastal landscape pattern stability.Based on the inflection point of landscape metrics and the maximum value of the MoranⅠindex,the optimal scale for analyzing coastal landscape pattern stability in Guangdong Province was 240 m×240 m.Within the past several decades,coastal landscape pattern stability increased slightly and then decreased,with a turning point around 2005.The most significant variations in coastal landscape pattern stability were observed in the transition zone of rural-urban expansion.A q-statistics analysis showed that the explanatory power of paired factors was greater than that of a single driving factor;the paired factors with the greatest impact on coastal landscape pattern stability in Guangdong Province were the change in gross industrial output and change in average annual precipitation from 2010 to 2015,based on a q value of 0.604.These results will contribute to future efforts to achieve sustainable coastal development and provide a scientific basis and technical support for the rational planning and utilization of resources in large estuarine areas,including marine disaster prevention and seawall ecological restoration.展开更多
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo...This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising.展开更多
This paper explores the convergence of a class of optimally conditioned self scaling variable metric (OCSSVM) methods for unconstrained optimization. We show that this class of methods with Wolfe line search are glob...This paper explores the convergence of a class of optimally conditioned self scaling variable metric (OCSSVM) methods for unconstrained optimization. We show that this class of methods with Wolfe line search are globally convergent for general convex functions.展开更多
This paper proposes a new search strategy using mutative scale chaos optimization algorithm (MSCO) for model selection of support vector machine (SVM). It searches the parameter space of SVM with a very high effic...This paper proposes a new search strategy using mutative scale chaos optimization algorithm (MSCO) for model selection of support vector machine (SVM). It searches the parameter space of SVM with a very high efficiency and finds the optimum parameter setting for a practical classification problem with very low time cost. To demonstrate the performance of the proposed method it is applied to model selection of SVM in ultrasonic flaw classification and compared with grid search for model selection. Experimental results show that MSCO is a very powerful tool for model selection of SVM, and outperforms grid search in search speed and precision in ultrasonic flaw classification.展开更多
The Internet of Things (IoT) and Cloud computing are gaining popularity due to their numerous advantages, including the efficient utilization of internetand computing resources. In recent years, many more IoT applicat...The Internet of Things (IoT) and Cloud computing are gaining popularity due to their numerous advantages, including the efficient utilization of internetand computing resources. In recent years, many more IoT applications have beenextensively used. For instance, Healthcare applications execute computations utilizing the user’s private data stored on cloud servers. However, the main obstaclesfaced by the extensive acceptance and usage of these emerging technologies aresecurity and privacy. Moreover, many healthcare data management system applications have emerged, offering solutions for distinct circumstances. But still, theexisting system has issues with specific security issues, privacy-preserving rate,information loss, etc. Hence, the overall system performance is reduced significantly. A unique blockchain-based technique is proposed to improve anonymityin terms of data access and data privacy to overcome the above-mentioned issues.Initially, the registration phase is done for the device and the user. After that, theGeo-Location and IP Address values collected during registration are convertedinto Hash values using Adler 32 hashing algorithm, and the private and publickeys are generated using the key generation centre. Then the authentication is performed through login. The user then submits a request to the blockchain server,which redirects the request to the associated IoT device in order to obtain thesensed IoT data. The detected data is anonymized in the device and stored inthe cloud server using the Linear Scaling based Rider Optimization algorithmwith integrated KL Anonymity (LSR-KLA) approach. After that, the Time-stamp-based Public and Private Key Schnorr Signature (TSPP-SS) mechanismis used to permit the authorized user to access the data, and the blockchain servertracks the entire transaction. The experimental findings showed that the proposedLSR-KLA and TSPP-SS technique provides better performance in terms of higherprivacy-preserving rate, lower information loss, execution time, and Central Processing Unit (CPU) usage than the existing techniques. Thus, the proposed method allows for better data privacy in the smart healthcare network.展开更多
[Objective] This study was to provide references for the improvement of agricultural economic benefit by analyzing the main factors on influencing the economic benefit of rice farmer. [Method] Field survey was carried...[Objective] This study was to provide references for the improvement of agricultural economic benefit by analyzing the main factors on influencing the economic benefit of rice farmer. [Method] Field survey was carried out on 300 rice farmers in Suizhou, Wuxue and Xiaogan of Hubei Province. Through the descriptive statistics to the production input and output data of the sample farmers, the econometric model was established to conduct empirical test on the economic benefit of rice farmer and the influential factors. The optimal production scale for rice farmer was also estimated, and through the theoretical and empirical analysis of the optimal production scale, countermeasures were put forward with the aim to promote economic benefit of rice farmer. [Result] The application of fertilizer affected the economic benefit most, followed by the planting area; food policy, farming population and average economic income per capita had significant effects on the economic benefit of rice production; economic benefit was beneficial for cost control. [Conclusion] This study had great practical and instructive significance for stabilizing national food production, ensuring regional and national food safety.展开更多
In this paper, a new event detection pitch detector based on the dyadic wavelet transform was constrcted by selecting an optimal scale. The proposed pitch detector is accurate, robust to noise and computationally simp...In this paper, a new event detection pitch detector based on the dyadic wavelet transform was constrcted by selecting an optimal scale. The proposed pitch detector is accurate, robust to noise and computationally simple. Experiments show the superior performance of this event-based pitch detector in comparison with previous event-based pitch detector and classical pitch detectors that use the autocorrelation and the cepsmun methods to estimate the pitch period.展开更多
We studied the information search behaviors of Chinese consumers of miniature automobiles. First, we identified the main sources where consumers acquire or seek information about miniature automobiles and discussed th...We studied the information search behaviors of Chinese consumers of miniature automobiles. First, we identified the main sources where consumers acquire or seek information about miniature automobiles and discussed their extent of information search. Then, based on logistic regression and optimal scaling regression of statistics, we studied the influences of characteristics of consumers of miniature automobiles on the extent of information search and on Internet usage. The results indicate that consumers often utilize four sources to obtain information about miniature automobiles. The dominant information source for consumers is their friends/family, followed by dealers, newspapers, and TV. Age, occupation, education and income significantly affect the extent of information search, but gender and city of residence do not have significant impacts. Age, city of residence, occupation, education and income produce significant influences on Internet usage. Gender has an insignificant influence on whether a consumer uses the Internet to search for information.展开更多
A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problem...A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problems.The SGSO adopts an improved sharing strategy which shares information of not only the best member but also the other good members,and uses a simpler search method instead of searching by the head angle.Furthermore,the SGSO increases the percentage of scroungers to accelerate convergence speed.Compared with genetic algorithm(GA),particle swarm optimizer(PSO)and group search optimizer(GSO),SGSO is tested on seven benchmark functions with dimensions 30,100,500 and 1 000.It can be concluded that the SGSO has a remarkably superior performance to GA,PSO and GSO for large scale global optimization.展开更多
Long diversion system of hydropower station, including surge tank, inlet tunnel and penstock, is an inseparable whole system. Scale effects of distorted model on the diversion system are studied in the present paper. ...Long diversion system of hydropower station, including surge tank, inlet tunnel and penstock, is an inseparable whole system. Scale effects of distorted model on the diversion system are studied in the present paper. Based on the concept of model scale correlation and the method of parameter expression of model scale, the model scale optimization can be realized. Furthermore, a quantitative criterion for the choice of distorted model or normal model is presented. The study shows that distorted model can simultaneously satisfy the similarity conditions derived from surge wave equations, water hammer equations and wave speed equation for the diversion system. In addition, an example for the design of a practical distorted model is provided.展开更多
In this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming (SCP). A predictor-corrector interior point method is applied to solve the strictly convex s...In this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming (SCP). A predictor-corrector interior point method is applied to solve the strictly convex subproblems. The SCP algorithm and the topology optimization approach are introduced. Especially, different strategies to solve certain linear systems of equations are analyzed. Numerical results are presented to show the efficiency of the proposed method for solving topology optimization problems and to compare different variants.展开更多
Monotonic regression (MR) is a least distance problem with monotonicity constraints induced by a partiaily ordered data set of observations. In our recent publication [In Ser. Nonconvex Optimization and Its Applicat...Monotonic regression (MR) is a least distance problem with monotonicity constraints induced by a partiaily ordered data set of observations. In our recent publication [In Ser. Nonconvex Optimization and Its Applications, Springer-Verlag, (2006) 83, pp. 25-33], the Pool-Adjazent-Violators algorithm (PAV) was generalized from completely to partially ordered data sets (posets). The new algorithm, called CPAV, is characterized by the very low computational complexity, which is of second order in the number of observations. It treats the observations in a consecutive order, and it can follow any arbitrarily chosen topological order of the poset of observations. The CPAV algorithm produces a sufficiently accurate solution to the MR problem, but the accuracy depends on the chosen topological order. Here we prove that there exists a topological order for which the resulted CPAV solution is optimal. Furthermore, we present results of extensive numerical experiments, from which we draw conclusions about the most and the least preferable topological orders.展开更多
基金Supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education,No. NRF-2018R1D1A1B07041091 and No. NRF-2021S1A5A80625262022 Development of Open-Lab based on 4P in the Southeast Zone
文摘BACKGROUND Efficiently detecting Parkinson's disease(PD)with dementia(PDD)as soon as possible is an important issue in geriatric medicine.AIM To develop a model for predicting PDD based on various neuropsychological tests using data from a nationwide survey conducted by the Korean Centers for Disease Control and Prevention and to present baseline data for the early detection of PDD.METHODS This study comprised 289 patients who were 60 years or older with PD[110 with PDD and 179 Parkinson's Disease-Mild Cognitive Impairment(PD-MCI)].Regression with optimal scaling(ROS)was used to identify independent relationships between the neuropsychological test results and PDD.RESULTS In the ROS analysis,Korean version of mini mental state ex-amination(MMSE)(KOREAN version of MMSE)(b=-0.52,SE=0.16)and Hoehn and Yahr staging(b=0.44,SE=0.19)were significantly effective models for distinguishing PDD from PD-MCI(P<0.05),even after adjusting for all of the Parkinson's motor symptom and neuropsychological test results.The optimal number of categories(scaling factors)for KOREAN version of MMSE and Hoehn and Yahr Scale was 10 and 7,respectively.CONCLUSION The results of this study suggest that among the various neuropsychological tests conducted,the optimal classification scores for KOREAN version of MMSE and Hoehn and Yahr Scale could be utilized as an effective screening test for the early discrimination of PDD from PD-MCI.
基金Supported by Science and Technology Project of Guiyang Company of Guizhou Provincial Tobacco Company"Study on Cultivation of New Type Tobacco Operation Entities in Guiyang Tobacco Area"(2022-06)Students’Platform for Innovation and Entrepreneurship Training Program of Colleges and Universities in Henan Province"Study on Cultivation of New Professional Tobacco Farmers with Family Farms as the Carrier"(202210466045)。
文摘The larger the difference between the willingness scale of tobacco family farmers and the optimal scale of efficiency,the greater the degree of irrationality,and the higher the decision making risk.With the aid of DEA model,this study calculated the optimal scale of efficiency of Guiyang tobacco family farms.Using the ratio of willingness scale and efficiency optimal scale,it measured the degree of irrationality of family farmers.In addition,with the help of multiple linear regression model,it explained the irrational decision making mechanism of family farmers.Finally,it made a portrait of farmers who tend to make irrational decisions,to find specific farmers and guide them in their production and operation,reduce the risk of planting scale decision making and stabilize the sustainable development of the tobacco industry.
文摘Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance.
基金The National Natural Science Foundation of China under contract Nos 42201104 and 42071123the China Postdoctoral Research Foundation under contract No.2023M730758.
文摘The long-term dynamic evolution and underlying mechanisms of coastal landscape pattern stability,driven by strong anthropogenic interference and consequently climate change,are topics of major interest in national and international scientific research.Guangdong Province,located in southeastern China,has been undergoing rapid urbanization over several decades.In this study,we quantitatively determined the scale threshold characteristics of coastal landscape pattern stability in Guangdong Province,from the dual perspective of spatial heterogeneity and spatial autocorrelation.An analysis of the spatiotemporal evolution of the coastal landscape was conducted after the optical scale was determined.Then,we applied the geodetector statistical method to quantitatively explore the mechanisms underlying coastal landscape pattern stability.Based on the inflection point of landscape metrics and the maximum value of the MoranⅠindex,the optimal scale for analyzing coastal landscape pattern stability in Guangdong Province was 240 m×240 m.Within the past several decades,coastal landscape pattern stability increased slightly and then decreased,with a turning point around 2005.The most significant variations in coastal landscape pattern stability were observed in the transition zone of rural-urban expansion.A q-statistics analysis showed that the explanatory power of paired factors was greater than that of a single driving factor;the paired factors with the greatest impact on coastal landscape pattern stability in Guangdong Province were the change in gross industrial output and change in average annual precipitation from 2010 to 2015,based on a q value of 0.604.These results will contribute to future efforts to achieve sustainable coastal development and provide a scientific basis and technical support for the rational planning and utilization of resources in large estuarine areas,including marine disaster prevention and seawall ecological restoration.
基金supported by the National Natural Science Foundation of China(12171106)the Natural Science Foundation of Guangxi Province(2020GXNSFDA238017 and 2018GXNSFFA281007)the Shanghai Sailing Program(21YF1430300)。
文摘This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising.
文摘This paper explores the convergence of a class of optimally conditioned self scaling variable metric (OCSSVM) methods for unconstrained optimization. We show that this class of methods with Wolfe line search are globally convergent for general convex functions.
基金Project supported by National High-Technology Research and De-velopment Program of China (Grant No .863-2001AA602021)
文摘This paper proposes a new search strategy using mutative scale chaos optimization algorithm (MSCO) for model selection of support vector machine (SVM). It searches the parameter space of SVM with a very high efficiency and finds the optimum parameter setting for a practical classification problem with very low time cost. To demonstrate the performance of the proposed method it is applied to model selection of SVM in ultrasonic flaw classification and compared with grid search for model selection. Experimental results show that MSCO is a very powerful tool for model selection of SVM, and outperforms grid search in search speed and precision in ultrasonic flaw classification.
文摘The Internet of Things (IoT) and Cloud computing are gaining popularity due to their numerous advantages, including the efficient utilization of internetand computing resources. In recent years, many more IoT applications have beenextensively used. For instance, Healthcare applications execute computations utilizing the user’s private data stored on cloud servers. However, the main obstaclesfaced by the extensive acceptance and usage of these emerging technologies aresecurity and privacy. Moreover, many healthcare data management system applications have emerged, offering solutions for distinct circumstances. But still, theexisting system has issues with specific security issues, privacy-preserving rate,information loss, etc. Hence, the overall system performance is reduced significantly. A unique blockchain-based technique is proposed to improve anonymityin terms of data access and data privacy to overcome the above-mentioned issues.Initially, the registration phase is done for the device and the user. After that, theGeo-Location and IP Address values collected during registration are convertedinto Hash values using Adler 32 hashing algorithm, and the private and publickeys are generated using the key generation centre. Then the authentication is performed through login. The user then submits a request to the blockchain server,which redirects the request to the associated IoT device in order to obtain thesensed IoT data. The detected data is anonymized in the device and stored inthe cloud server using the Linear Scaling based Rider Optimization algorithmwith integrated KL Anonymity (LSR-KLA) approach. After that, the Time-stamp-based Public and Private Key Schnorr Signature (TSPP-SS) mechanismis used to permit the authorized user to access the data, and the blockchain servertracks the entire transaction. The experimental findings showed that the proposedLSR-KLA and TSPP-SS technique provides better performance in terms of higherprivacy-preserving rate, lower information loss, execution time, and Central Processing Unit (CPU) usage than the existing techniques. Thus, the proposed method allows for better data privacy in the smart healthcare network.
基金Supported by the"Insect-resistant Transgenic Rice Cultivation"of National Key Transgenic Project(2011ZX08001-001)the Earmarked Fund for China Agriculture Research System(CARS-01-10B)the Special Fund for Agro-scientific Research(201003016)~~
文摘[Objective] This study was to provide references for the improvement of agricultural economic benefit by analyzing the main factors on influencing the economic benefit of rice farmer. [Method] Field survey was carried out on 300 rice farmers in Suizhou, Wuxue and Xiaogan of Hubei Province. Through the descriptive statistics to the production input and output data of the sample farmers, the econometric model was established to conduct empirical test on the economic benefit of rice farmer and the influential factors. The optimal production scale for rice farmer was also estimated, and through the theoretical and empirical analysis of the optimal production scale, countermeasures were put forward with the aim to promote economic benefit of rice farmer. [Result] The application of fertilizer affected the economic benefit most, followed by the planting area; food policy, farming population and average economic income per capita had significant effects on the economic benefit of rice production; economic benefit was beneficial for cost control. [Conclusion] This study had great practical and instructive significance for stabilizing national food production, ensuring regional and national food safety.
文摘In this paper, a new event detection pitch detector based on the dyadic wavelet transform was constrcted by selecting an optimal scale. The proposed pitch detector is accurate, robust to noise and computationally simple. Experiments show the superior performance of this event-based pitch detector in comparison with previous event-based pitch detector and classical pitch detectors that use the autocorrelation and the cepsmun methods to estimate the pitch period.
基金the Natural Science Foundation of China ( No. 70472016).
文摘We studied the information search behaviors of Chinese consumers of miniature automobiles. First, we identified the main sources where consumers acquire or seek information about miniature automobiles and discussed their extent of information search. Then, based on logistic regression and optimal scaling regression of statistics, we studied the influences of characteristics of consumers of miniature automobiles on the extent of information search and on Internet usage. The results indicate that consumers often utilize four sources to obtain information about miniature automobiles. The dominant information source for consumers is their friends/family, followed by dealers, newspapers, and TV. Age, occupation, education and income significantly affect the extent of information search, but gender and city of residence do not have significant impacts. Age, city of residence, occupation, education and income produce significant influences on Internet usage. Gender has an insignificant influence on whether a consumer uses the Internet to search for information.
基金the Science and Technology Planning Project of Hunan Province(No.2011TP4016-3)the Construct Program of the Key Discipline(Technology of Computer Application)in Xiangnan University
文摘A simplified group search optimizer algorithm denoted as"SGSO"for large scale global optimization is presented in this paper to obtain a simple algorithm with superior performance on high-dimensional problems.The SGSO adopts an improved sharing strategy which shares information of not only the best member but also the other good members,and uses a simpler search method instead of searching by the head angle.Furthermore,the SGSO increases the percentage of scroungers to accelerate convergence speed.Compared with genetic algorithm(GA),particle swarm optimizer(PSO)and group search optimizer(GSO),SGSO is tested on seven benchmark functions with dimensions 30,100,500 and 1 000.It can be concluded that the SGSO has a remarkably superior performance to GA,PSO and GSO for large scale global optimization.
文摘Long diversion system of hydropower station, including surge tank, inlet tunnel and penstock, is an inseparable whole system. Scale effects of distorted model on the diversion system are studied in the present paper. Based on the concept of model scale correlation and the method of parameter expression of model scale, the model scale optimization can be realized. Furthermore, a quantitative criterion for the choice of distorted model or normal model is presented. The study shows that distorted model can simultaneously satisfy the similarity conditions derived from surge wave equations, water hammer equations and wave speed equation for the diversion system. In addition, an example for the design of a practical distorted model is provided.
基金This work was mainly done while the first author was visiting the University of Bayreuth, and was supported by the Chinese Scholarship Council, German Academic Exchange Service (DAAD) and the National Natural Science Foundation of China.
文摘In this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming (SCP). A predictor-corrector interior point method is applied to solve the strictly convex subproblems. The SCP algorithm and the topology optimization approach are introduced. Especially, different strategies to solve certain linear systems of equations are analyzed. Numerical results are presented to show the efficiency of the proposed method for solving topology optimization problems and to compare different variants.
文摘Monotonic regression (MR) is a least distance problem with monotonicity constraints induced by a partiaily ordered data set of observations. In our recent publication [In Ser. Nonconvex Optimization and Its Applications, Springer-Verlag, (2006) 83, pp. 25-33], the Pool-Adjazent-Violators algorithm (PAV) was generalized from completely to partially ordered data sets (posets). The new algorithm, called CPAV, is characterized by the very low computational complexity, which is of second order in the number of observations. It treats the observations in a consecutive order, and it can follow any arbitrarily chosen topological order of the poset of observations. The CPAV algorithm produces a sufficiently accurate solution to the MR problem, but the accuracy depends on the chosen topological order. Here we prove that there exists a topological order for which the resulted CPAV solution is optimal. Furthermore, we present results of extensive numerical experiments, from which we draw conclusions about the most and the least preferable topological orders.