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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation regional large-scale Online recognition Feature extraction method
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UNIQUENESS OF SOLUTION OF FIELD POINT OF SINGULAR SOURCE OUTSIDE-REGION-DISTRIBUTION METHOD
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作者 云天铨 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第1期36-42,共7页
The uniqueness of solution of field point, inside a convex region due to singular source(s) with kernel function decreasing with distance increasing, outside-region-distribution(s) such that the boundary condition exp... The uniqueness of solution of field point, inside a convex region due to singular source(s) with kernel function decreasing with distance increasing, outside-region-distribution(s) such that the boundary condition expressed by the response of the source(s) is satisfied, is proved by using the condition of kernel function decreasing with distance increasing anal an integral inequality. Examples of part of these singular sources such as Kelvin's point force, Point-Ring-Couple (PRC) etc. are given. The proof of uniqueness of solution of field point in a twisted shaft of revolution due to PRC distribution is given as an example of application. 展开更多
关键词 solution of singular sources singular source outside-region distribution method non-singular integral equation method boundary element method line-loaded integral equation method
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Effects of Mapping Methods on Accuracy of Protein Coding Regions Prediction
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作者 马玉韬 张成 +2 位作者 杨泽林 李琦 杨婷 《Agricultural Science & Technology》 CAS 2011年第12期1802-1806,1860,共6页
[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlatio... [Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation(AC) as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter(WNPBF) based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric(PN),Electron-ion Interaction Potential(EIIP) and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods. 展开更多
关键词 Prediction accuracy Protein coding regions Mapping method Windowed Narrow pass-band filter
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A NONMONOTONE TRUST REGION METHOD FOR NONLINEAR LEAST SQUARES PROBLEMS
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作者 邓乃扬 肖奕 +1 位作者 周方俊 吴育华 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1994年第1期33-53,共21页
In this paper we present a nonmonotone trust region method for nonlinear least squares problems with zero-residual and prove its convergence properties. The extensive numerical results are reported which show that the... In this paper we present a nonmonotone trust region method for nonlinear least squares problems with zero-residual and prove its convergence properties. The extensive numerical results are reported which show that the nonmonotone trust region method is generally superior to the usual trust region method. 展开更多
关键词 TRUST region method NONLINEAR least SQUARES NONMONOTONE method.
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Review on Quantitative Research Methods of Regional Sustainable Development in China
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作者 Zhang Jinping Qin Yaochen Zhang Erxun 《Chinese Journal of Population,Resources and Environment》 2010年第3期44-53,共10页
Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD fro... Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD from Core Periodical in China National Knowledge Infrastructure (1992–2008), statistical analysis on the annual distribution, periodicals distribution and changes of the distribution were made. And from perspectives of social–economic, ecological, systematic and emerging methods, the course, problems and trends of the quantitative study methods on RSD were examined and analyzed to get a clear summary. By the review, the context on the quantitative study of RSD was to be clarified. The study also showed that, primarily, fields involving quantitative study are expanding; second, big progresses and constant development have been made on the systematic method gradually sophisticated, the flourishing ecological method and emerging new methods in the context of cross and integration which has made complex integrated systems a more satisfactory solution; third, the method system has been more multi-angled, and the clues of independent innovation have been observed despite the fact that the introduction of imported method is the main trend. Although many problems exist, multi-scale study, dynamic timeseries study and inter-regional comparative study will be further exploited and increasingly carried out with the progress of spatial information technology, which would boost the development and application of new methods in RSD study. 展开更多
关键词 regional sustainable development quantitative research models systematic methods ecological methods
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Methods for Estimating Mean Annual Rate of Earthquakes in Moderate and Low Seismicity Regions
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作者 Peng Yanju Zhang Lifang Lv Yuejun Xie Zhuojuan 《Earthquake Research in China》 2012年第3期335-347,共13页
Two kinds of methods for determining seismic parameters are presented, that is, the potential seismic source zoning method and grid-spatially smoothing method. The Gaussian smoothing method and the modified Gaussian s... Two kinds of methods for determining seismic parameters are presented, that is, the potential seismic source zoning method and grid-spatially smoothing method. The Gaussian smoothing method and the modified Gaussian smoothing method are described in detail, and a comprehensive analysis of the advantages and disadvantages of these methods is made. Then, we take centrai China as the study region, and use the Gaussian smoothing method and potential seismic source zoning method to build seismic models to calculate the mean annual seismic rate. Seismic hazard is calculated using the probabilistic seismic hazard analysis method to construct the ground motion acceleration zoning maps. The differences between the maps and these models are discussed and the causes are investigated. The results show that the spatial smoothing method is suitable for estimating the seismic hazard over the moderate and low seismicity regions or the hazard caused by background seismicity; while the potential seismic source zoning method is suitable for estimating the seismic hazard in well-defined seismotectonics. Combining the spatial smoothing method and the potential seismic source zoning method with an integrated account of the seismicity and known seismotectonics is a feasible approach to estimate the seismic hazard in moderate and low seismicity regions. 展开更多
关键词 Moderate and low seismicity regions Annual seismic activity rate Grid-spatially smoothing method Potential seismic source zoning method
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Can regional economy influence China's water use intensity?:based on refined LMDI method 被引量:4
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作者 Chenjun Zhang Hengquan Zhang 《Chinese Journal of Population,Resources and Environment》 2014年第3期247-254,共8页
China experienced a decline of water use intensity in the 11th Five Year Plan,but the water use intensity actually increased in 2009.To the best of our knowledge,the index decomposition analysis method was rarely used... China experienced a decline of water use intensity in the 11th Five Year Plan,but the water use intensity actually increased in 2009.To the best of our knowledge,the index decomposition analysis method was rarely used to analyze changes in water use,and no decomposition analysis has investigated the role of regional economy in the decline of water use intensity.In this paper,we use logarithmic mean Divisia index(LMDI)techniques to decompose the change of water use intensity in the period 2006-2010.We find that the change of industrial water use intensity is confirmed as the dominant contributor to the decline in the overall water use intensity;the regional structure effect and the industrial structure effect is positive to the decline of overall water use intensity;the decline of China's water use intensity is mainly attributed to the effect of developed eastern provinces;meanwhile,the effect of central and undeveloped western is also positive to the decline of overall water use intensity;at least one out of three effects is positive to the decline of water use intensity in the different provinces;the intensity effect is positive and the industrial structure effect is positive to the declines of China's water use intensity based on chaining approach except the period 2008-2009,individually;and the deviation of regional structure effect and industrial structure effect between with regional economy and without regional economy in LMDI is 0.9 and2.3 m^3/10~4 RMB,respectively. 展开更多
关键词 water use INTENSITY DECOMPOSITION refined LMDI method regionAL ECONOMY
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A preliminary study on the theory and method of comprehensiveregionalization of cryospheric services 被引量:5
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作者 LIN Hao-Xi HUANG Jin-Chuan +2 位作者 FANG Chuang-Lin QI Xiao-Xiao CHEN Yun-Qian 《Advances in Climate Change Research》 SCIE CSCD 2019年第2期115-123,共9页
As one of the five most important spheres affecting climate systems globally, the cryosphere not only exerts crucial impacts on natural environment, but also plays a key role in guaranteeing the goods and services pro... As one of the five most important spheres affecting climate systems globally, the cryosphere not only exerts crucial impacts on natural environment, but also plays a key role in guaranteeing the goods and services provision of the oasis in the cold and arid regions. However, there is a lack of synthesized knowledge about the contributions and profitability on socio-economic aspects of the cryospheric services (CSs). To cope with this key and urgent sustainable development issues, this study constructs a comprehensive regionalization research system that integrates the natural and socio-economic aspects for cryospheric characteristics with emphasis on interdisciplinary approaches. Guided by the supply- demand equilibrium model and the service maximization model, the research system consists of establishing a classification system for CSs, identifying the spatial distribution pattern of CSs, and constructing the comprehensive regionalization of CSs, which finally divides the research area into relatively independent, complete, and organically linked CS units of multiple spatial levels. By setting up a bridge between the CSs with socio-economic needs, it has profound and practical significance and implications for implementing the sustainable utilization strategies and macroeconomic policymaking for global environmental protection. 展开更多
关键词 PRINCIPLE method Service COMPREHENSIVE regionALIZATION CRYOSPHERE
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Discussion on the Assessment Method of Wind Energy Resources by Using Regional Meteorological Data 被引量:4
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作者 HE Jie-yan DAI Yu +3 位作者 JIN Xuan-xi LV Xiao-hua WANG Wei-nong LIU Cong-sheng 《Meteorological and Environmental Research》 CAS 2011年第2期10-12,17,共4页
The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resource... The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resources by using data from regional meteorological station was studied taking Huangjin Regional Meteorological Station in Xinning County in Hunan Province for example, besides, corresponding software was compiled. By means of SQL database and program, the method was used simply and easily and had positive meaning for the development of wind energy resources and excavation of wind farm in inland region. 展开更多
关键词 regional meteorological station Wind energy resources Assessment method China
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Analysis and comparison of spatial interpolation methods for temperature data in Xinjiang Uygur Autonomous Region, China 被引量:4
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作者 Huixia Chai Weiming Cheng +3 位作者 Chenghu Zhou Xi Chen Xiaoyi Ma Shangming Zhao 《Natural Science》 2011年第12期999-1010,共12页
Spatial interpolation methods are frequently used to estimate values of meteorological data in locations where they are not measured. However, very little research has been investigated the relative performance of dif... Spatial interpolation methods are frequently used to estimate values of meteorological data in locations where they are not measured. However, very little research has been investigated the relative performance of different interpolation methods in meteorological data of Xinjiang Uygur Autonomous Region (Xinjiang). Actually, it has importantly practical significance to as far as possibly improve the accuracy of interpolation results for meteorological data, especially in mountainous Xinjiang. There- fore, this paper focuses on the performance of different spatial interpolation methods for monthly temperature data in Xinjiang. The daily observed data of temperature are collected from 38 meteorological stations for the period 1960- 2004. Inverse distance weighting (IDW), ordinary kriging (OK), temperature lapse rate method (TLR) and multiple linear regressions (MLR) are selected as interpolated methods. Two rasterized methods, multiple regression plus space residual error and directly interpolated observed temperature (DIOT) data, are used to analyze and compare the performance of these interpolation methods respectively. Moreover, cross-validation is used to evaluate the performance of different spatial interpolation methods. The results are as follows: 1) The method of DIOT is unsuitable for the study area in this paper. 2) It is important to process the observed data by local regression model before the spatial interpolation. 3) The MLR-IDW is the optimum spatial interpolation method for the monthly mean temperature based on cross-validation. For the authors, the reliability of results and the influence of measurement accuracy, density, distribution and spatial variability on the accuracy of the interpolation methods will be tested and analyzed in the future. 展开更多
关键词 Spatial INTERPOLATION method CROSS validation MONTHLY Mean Temperature XINJIANG UYGUR AUTONOMOUS region
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A Nonmonotone Trust Region Method for Solving Symmetric Nonlinear Equations 被引量:3
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作者 YUAN Gong-lin WEI Zeng-xin LU Xi-wen 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期574-584,共11页
A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical res... A trust region method combining with nonmonotone technique is proposed tor solving symmetric nonlinear equations. The global convergence of the given method will be established under suitable conditions. Numerical results show that the method is interesting for the given problems. 展开更多
关键词 trust region method nonlinear equations nonmonotone technique
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A TRUST REGION METHOD FOR MICROWAVE TOMOGRAPHY 被引量:1
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作者 Gong Xing (Dept. of Biomedical Engineering, Zhejiang University, Hangzhou 310027) 《Journal of Electronics(China)》 2001年第2期181-184,共4页
A trust region method is proposed to solve the problem of microwave tomography,which is very difficult to be solved for its ill-posedness and nonlinearity. Compared with the Levenberg-Marquardt method, this method int... A trust region method is proposed to solve the problem of microwave tomography,which is very difficult to be solved for its ill-posedness and nonlinearity. Compared with the Levenberg-Marquardt method, this method introduces more a priori knowledge and might obtain better results, though the two methods are equal in some cases. 展开更多
关键词 MICROWAVE TOMOGRAPHY IMAGE RECONSTRUCTION TRUST region method
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A GLOBALLY AND SUPERLINEARLY CONVERGENT TRUST REGION METHOD FOR LC^1 OPTIMIZATION PROBLEMS 被引量:1
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作者 Zhang Liping Lai Yanlian Institute of Applied Mathematics,Academia Sinica,Beijing 100080. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第1期72-80,共9页
A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assum... A new trust region algorithm for solving convex LC 1 optimization problem is presented.It is proved that the algorithm is globally convergent and the rate of convergence is superlinear under some reasonable assumptions. 展开更多
关键词 LC 1 optimization problem global and superlinear convergence trust region method.
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A TRUST REGION METHOD WITH A CONIC MODEL FOR NONLINEARLY CONSTRAINED OPTIMIZATION 被引量:1
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作者 Wang Chengjing 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第3期263-275,共13页
Trust region methods are powerful and effective optimization methods. The conic model method is a new type of method with more information available at each iteration than standard quadratic-based methods. The adva... Trust region methods are powerful and effective optimization methods. The conic model method is a new type of method with more information available at each iteration than standard quadratic-based methods. The advantages of the above two methods can be combined to form a more powerful method for constrained optimization. The trust region subproblem of our method is to minimize a conic function subject to the linearized constraints and trust region bound. At the same time, the new algorithm still possesses robust global properties. The global convergence of the new algorithm under standard conditions is established. 展开更多
关键词 trust region method conic model constrained optimization nonlinear programming.
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High-temperature thermal stability of C/C−ZrC−SiC composites via region labeling method 被引量:2
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作者 Zheng PENG Chun-mao MIAO +5 位作者 Wei SUN Yong-long XU Hai-kun CHEN Yu-feng LIU Hong-bo ZHANG Xiang XIONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第10期3349-3361,共13页
To investigate the thermal stability of ceramic-matrix composites,three kinds of C/C−ZrC−SiC composites with different Zr/Si molar ratios were synthesized by reactive melt infiltration.Employing region labeling method... To investigate the thermal stability of ceramic-matrix composites,three kinds of C/C−ZrC−SiC composites with different Zr/Si molar ratios were synthesized by reactive melt infiltration.Employing region labeling method,the high-temperature thermal stability of the composites was systematically studied by changing the temperature and holding time of thermal treatment.Results show that the mass loss rate of low Si composites has a growth trend with increasing temperature,and a crystal transformation from β-SiC toα-SiC occurs in the composites.In the calibrated area,SiC phase experiences Ostwald ripening and volume change with location migration,while ZrC phase experiences a re-sintering process with diffusion.Moreover,it is found that increasing temperature has a more obvious effect on the thermal stability than extending holding time,which is mainly attributed to the faster diffusion rate of atoms. 展开更多
关键词 thermal stability ceramic-matrix composites reactive melt infiltration high-temperature thermal treatment region labeling method
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A FILTER-TRUST-REGION METHOD FOR LC^1 UNCONSTRAINED OPTIMIZATION AND ITS GLOBAL CONVERGENCE 被引量:1
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作者 ZhenghaoYang Wenyu Sun Chuangyin Dang 《Analysis in Theory and Applications》 2008年第1期55-66,共12页
In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorith... In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorithm under reasonable assumptions. 展开更多
关键词 nonsmooth optimization filter method trust region algorithm global conver- gence LC1 optimization
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Applying the AHP-FUZZY method to evaluate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau: a case study of Chaidaer-Muli Railway 被引量:1
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作者 Wei Cao Yu Sheng +1 位作者 Ji Chen JiChun Wu 《Research in Cold and Arid Regions》 CSCD 2018年第6期447-457,共11页
This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of ru... This article attempts to investigate the measure effect of rubble roadbed engineering in permafrost regions of Qinghai-Tibet Plateau. As a case study, Chaidaer-Muli Railway is used to evaluate the measure effect of rubble roadbed engineering in permafrost regions. The AHP(Analytic Hierarchy Process) method is thus employed to establish the evaluation indicator system. The evaluation factor is selected by analyzing the mutual relation between the permafrost environment and roadbed engineering. Thus, a hierarchical structure model is established based on the selected evaluation indices. Each factor is weighted to determine the status in the evaluation system, and grading standards are built for providing a basis for the evaluation. Then, the fuzzy mathematical method is introduced to evaluate the measure effect of rubble roadbed engineering in permafrost regions along the Chadaer-Muli Railway. Results show that most of the permafrost roadbed is in a preferable condition(b) along the Chaidaer-Muli Railway due to rubble engineering measures. This proportion reaches to 86.1%. The proportion in good(a), general(c) and poor states(d) are 0.0%, 7.5% and 6.4%, respectively, in all the evaluation sections along the Chaidaer-Muli Railway. Ground-temperature monitoring results are generally consistent with AHP-FUZZY evaluation results. This means that the AHP-FUZZY method can be applied to evaluate the effect of rubble roadbed engineering measures in permafrost regions. The effect evaluation of engineering measures will provide timely and effective feedback information for further engineering design. The series of engineering measures will more effectively protect permafrost stability. 展开更多
关键词 measure effect evaluation rubble roadbed engineering permafrost regions of Qinghai-Tibet Plateau AHP-FUZZY method Chaidaer-Muli Railway
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Planning method for AUV region detection under ocean current 被引量:1
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作者 ZHANGMing-jun HANZhi-xue 《Journal of Marine Science and Application》 2004年第1期46-51,共6页
In this paper we present two strategies of AUV (Autonomous Underwater Vehicle) region detection and an approach to decompose the detection region according to the direction of the ocean current. In the task of local d... In this paper we present two strategies of AUV (Autonomous Underwater Vehicle) region detection and an approach to decompose the detection region according to the direction of the ocean current. In the task of local detection and identification, the algorithm against the ocean current was proposed. In the tasks of closing obstacle, going back or moving, the fuzzy logic theory was used to solve the effect of ocean current. In one of our strategies the concept of weighted journey based on the angle between heading and ocean current is suggested and the TSP's exact optimal result is utilized to solve the global path planning. Simulations demonstrate the feasibility of this approach. 展开更多
关键词 AUV ocean current region detection planning method
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Experience and Methods for Maize Regional Experiment in Guizhou Mountainous Areas 被引量:1
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作者 周国富 王国忠 陈恩瑞 《Agricultural Science & Technology》 CAS 2016年第2期347-348,416,共3页
Maize regional experiment is a an intermediate link for overall assessment and comprehensive evaluation on yielding ability, stable yield, stress, adaptability, and quality traits of new maize varieties in different e... Maize regional experiment is a an intermediate link for overall assessment and comprehensive evaluation on yielding ability, stable yield, stress, adaptability, and quality traits of new maize varieties in different ecological conditions. It is an essential process for determining whether the new maize varieties can pass the ex- amination and approval for extension. Besides, regional experiment is an important link connecting agricultural scientific researches and agricultural production. In addi- tion, it is a scientific basis for extension and application of new maize varieties in a region. Therefore, the maize regional experiment is of the utmost importance. 展开更多
关键词 Maize regional experiment Guizhou mountainous areas Experience and methods
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A New Nonmonotone Adaptive Trust Region Method 被引量:1
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作者 Yang Zhang Quanming Ji Qinghua Zhou 《Journal of Applied Mathematics and Physics》 2021年第12期3102-3114,共13页
The trust region method plays an important role in solving optimization problems. In this paper, we propose a new nonmonotone adaptive trust region method for solving unconstrained optimization problems. Actually, we ... The trust region method plays an important role in solving optimization problems. In this paper, we propose a new nonmonotone adaptive trust region method for solving unconstrained optimization problems. Actually, we combine a popular nonmonotone technique with an adaptive trust region algorithm. The new ratio to adjusting the next trust region radius is different from the ratio in the traditional trust region methods. Under some appropriate conditions, we show that the new algorithm has good global convergence and superlinear convergence. 展开更多
关键词 Unconstrained Optimization Trust region method Nonmonotone Technique Global Convergence Superlinear Convergence
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