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Energy saving analysis of segment positioning in shield tunneling machine considering assembling path optimization 被引量:4
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作者 施虎 龚国芳 +1 位作者 杨华勇 梅雪松 《Journal of Central South University》 SCIE EI CAS 2014年第12期4526-4536,共11页
A motion parameter optimization method based on the objective of minimizing the total energy consumption in segment positioning was proposed for segment erector of shield tunneling machine. The segment positioning pro... A motion parameter optimization method based on the objective of minimizing the total energy consumption in segment positioning was proposed for segment erector of shield tunneling machine. The segment positioning process was decomposed into rotation, lifting and sliding actions in deriving the energy calculation model of segment erection. The work of gravity was taken into account in the mathematical modeling of energy consumed by each actuator. In order to investigate the relationship between the work done by the actuator and the path moved along by the segment, the upward and downward directions as well as the operating quadrant of the segment erector were defined. Piecewise nonlinear function of energy was presented, of which the result is determined by closely coupled components as working parameters and some intermediate variables. Finally, the effectiveness of the optimization method was proved by conducting a case study with a segment erector for the tunnel with a diameter of 3 m and drawing comparisons between different assembling paths. The results show that the energy required by assembling a ring of segments along the optimized moving path can be reduced up to 5%. The method proposed in this work definitely provides an effective energy saving solution for shield tunneling machine. 展开更多
关键词 energy saving segment erector work of gravity path optimization shield tunneling machine
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Plotting the Sequential Rock Remote Sensing Information by Optimization Dichotomy Method
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作者 Liu Qingsheng Lin Qizhong +1 位作者 Wang Zhigang Yan Shouxun(Institute of Remote Sensing Application, Chinese Academy of Sciences, Beijing 100101) 《Journal of Earth Science》 SCIE CAS CSCD 1999年第3期271-273,共3页
The sequential rock remote sensing information is a group of rocks that are correlative in space or in space and time. For the sake of plottiug them, someone had brought forward the optimization segn.entotion metkod. ... The sequential rock remote sensing information is a group of rocks that are correlative in space or in space and time. For the sake of plottiug them, someone had brought forward the optimization segn.entotion metkod. We have ased this method to plot the sequential rock remote sensing information at tbe remote sensing hyperspetral test field of Daqing mountain, Inner Mongolia Autonomous Region, China, and found some disadvantages of this method. Therefore, we put forward the optimization dichotomy to plot them, and get better results. Finally we make a conclusion. 展开更多
关键词 sequential rock remote sensing information optimization segmentation method optimization dichotomy method
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Study on the Optimization Algorithms for Intensity-Modulated Radiation Therapy
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作者 LIYong-jie 《Journal of Electronic Science and Technology of China》 2005年第1期95-96,共2页
关键词 intensity-modulated radiotherapy conjugate gradient (CG) method genetic algorithm (GA) segment optimization beam angle optimization expert knowledge
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Optimization of Quantizer’s Segment Threshold Using Spline Approximations for Optimal Compressor Function
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作者 Lazar Velimirovic Zoran Peric +1 位作者 Miomir Stankovic Jelena Nikolic 《Applied Mathematics》 2012年第10期1430-1434,共5页
In this paper, the optimization of quantizer’s segment threshold is done. The quantizer is designed on the basis of approximative spline functions. Coefficients on which we form approximative spline functions are cal... In this paper, the optimization of quantizer’s segment threshold is done. The quantizer is designed on the basis of approximative spline functions. Coefficients on which we form approximative spline functions are calculated by minimization mean square error (MSE). For coefficients determined in this way, spline functions by which optimal compressor function is approximated are obtained. For the quantizer designed on the basis of approximative spline functions, segment threshold is numerically determined depending on maximal value of the signal to quantization noise ratio (SQNR). Thus, quantizer with optimized segment threshold is achieved. It is shown that by quantizer model designed in this way and proposed in this paper, the SQNR that is very close to SQNR of nonlinear optimal companding quantizer is achieved. 展开更多
关键词 optimization of Quantizer’s Segment Threshold Mean Square Error Second-Degree Spline Functions Compressor Function
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An Adaptive Parameter-Free Optimal Number of Market Segments Estimation Algorithm Based on a New Internal Validity Index
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作者 Jianfang Qi Yue Li +3 位作者 Haibin Jin Jianying Feng Dong Tian Weisong Mu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期197-232,共36页
An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segm... An appropriate optimal number of market segments(ONS)estimation is essential for an enterprise to achieve successful market segmentation,but at present,there is a serious lack of attention to this issue in market segmentation.In our study,an independent adaptive ONS estimation method BWCON-NSDK-means++is proposed by integrating a newinternal validity index(IVI)Between-Within-Connectivity(BWCON)and a newstable clustering algorithmNatural-SDK-means++(NSDK-means++)in a novel way.First,to complete the evaluation dimensions of the existing IVIs,we designed a connectivity formula based on the neighbor relationship and proposed the BWCON by integrating the connectivity with other two commonly considered measures of compactness and separation.Then,considering the stability,number of parameters and clustering performance,we proposed the NSDK-means++to participate in the integrationwhere the natural neighbor was used to optimize the initial cluster centers(ICCs)determination strategy in the SDK-means++.At last,to ensure the objectivity of the estimatedONS,we designed a BWCON-based ONS estimation framework that does not require the user to set any parameters in advance and integrated the NSDK-means++into this framework forming a practical ONS estimation tool BWCON-NSDK-means++.The final experimental results showthat the proposed BWCONand NSDK-means++are significantlymore suitable than their respective existing models to participate in the integration for determining theONS,and the proposed BWCON-NSDK-means++is demonstrably superior to the BWCON-KMA,BWCONMBK,BWCON-KM++,BWCON-RKM++,BWCON-SDKM++,BWCON-Single linkage,BWCON-Complete linkage,BWCON-Average linkage and BWCON-Ward linkage in terms of the ONS estimation.Moreover,as an independentmarket segmentation tool,the BWCON-NSDK-means++also outperforms the existing models with respect to the inter-market differentiation and sub-market size. 展开更多
关键词 Optimal number of market segments internal validity index cluster connectivity SDK-means++ market segmentation
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Global optimization design method for maximizing the capacity of V-belt drive 被引量:5
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作者 ZHANG ShaoJun WAN Zhong LIUGuangLian 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第1期140-147,共8页
An optimization model is constructed to formulate the maximization problem on the capacity of V-belt drive. The concavity,the monotonicity and the global optimality condition are studied for the objective function,and... An optimization model is constructed to formulate the maximization problem on the capacity of V-belt drive. The concavity,the monotonicity and the global optimality condition are studied for the objective function,and it is proved that the feasible region of the model is bounded,closed and convex under some design conditions. Then,a solution method,called an optimal segment algorithm,is developed to find the global maximizer of the model. Under four different design conditions,solution methods are presented respectively. Some real case studies are employed to demonstrate that the model and the algorithm in this paper are promising. 展开更多
关键词 V.belt global optimization capacity of drive optimal segment algorithm
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Novel Model Using Kernel Function and Local Intensity Information for Noise Image Segmentation 被引量:2
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作者 Gang Li Haifang Li Ling Zhang 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2018年第3期303-314,共12页
It remains a challenging task to segment images that are distorted by noise and intensity inhomogeneity.To overcome these problems, in this paper, we present a novel region-based active contour model based on local in... It remains a challenging task to segment images that are distorted by noise and intensity inhomogeneity.To overcome these problems, in this paper, we present a novel region-based active contour model based on local intensity information and a kernel metric. By introducing intensity information about the local region, the proposed model can accurately segment images with intensity inhomogeneity. To enhance the model's robustness to noise and outliers, we introduce a kernel metric as its objective functional. To more accurately detect boundaries, we apply convex optimization to this new model, which uses a weighted total-variation norm given by an edge indicator function. Lastly, we use the split Bregman iteration method to obtain the numerical solution. We conducted an extensive series of experiments on both synthetic and real images to evaluate our proposed method, and the results demonstrate significant improvements in terms of efficiency and accuracy, compared with the performance of currently popular methods. 展开更多
关键词 kernel metric image segmentation local intensity information convex optimization
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Optimization of a Segmented Filter with a New Error Diffusion Approach
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作者 Ayman Al Falou Marwa ELBouz 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期853-854,共2页
The segmented filters, based on spectral cutting, proved their efficiency for the multi-correlation. In this article we propose an optimisation of this cutting according to a new error diffusion method.
关键词 of on in with optimization of a Segmented Filter with a New Error Diffusion Approach for
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