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As an effective approach for multi-input multi-output regression estimation problems, a multi-dimensional support vector regression (SVR), named M-SVR, is generally capable of obtaining better predictions than applying a conventional support vector machine (SVM) independently for each output dimension. However, although there are many generalization error bounds for conventional SVMs, all of them cannot be directly applied to M-SVR. In this paper, a new leave-one-out (LOO) error estimate for M-SVR is derived firstly through a virtual LOO cross-validation procedure. This LOO error estimate can be straightway calculated once a training process ended with less computational complexity than traditional LOO method. Based on this LOO estimate, a new model selection methods for M-SVR based on multi-objective optimization strategy is further proposed in this paper. Experiments on toy noisy function regression and practical engineering data set, that is, dynamic load identification on cylinder vibration system, are both conducted, demonstrating comparable results of the proposed method in terms of generalization performance and computational cost. 相似文献
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针对目前测量分析、弱信号检测的需求,以STM32F107和AD9958为核心实现了一种高分辨率幅度、频率、相位的双路信号源。首先对直接数字合成(Direct Digital Synthesis,DDS)工作原理进行介绍,重点分析了杂散的主要来源,并设计LC椭圆低通滤波器对杂散进行抑制。设计输出电路使信号源满足低频需求,并可直接用于驱动负载。最后采用STM32F107和VC6.0搭建了配置平台,对信号源波形灵活控制。 相似文献
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木又青 《网络安全技术与应用》2014,(9):213-213
当今社会疗养院建设快速推进,疗养院卫生信息化发展极为迅速.那么疗养院怎样根据自身情况,提高疗养院整体管理水平、规范各项医疗工作,已成为一个迫切需要解决的问题.这就要求疗养院必须提高自己的自身信息化建设水平,必须跟上社会卫生信息化建设步伐.本文对疗养院信息化建设的基本情况、遇到的主要问题及其今后发展的趋势进行了探讨.以促进疗养院信息化建设迅速健康的发展. 相似文献
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The temperature dependence of permeability through highly syndiotactic poly(2-hydroxyethyl methacrylate) [P(HEMA)] membrane is reported for highly polar organic solutes such as ureas, methyl substituted ureas and amides, and for NaCl and Na2SO4. The membranes used were equilibrated in distilled water at each temperature before measurements. From the linear correlationship between the excess heat capacities, ?Cpo(excess) in aqueous solution at infinite dilution and the permeability parameter PM1/3, it is found that the water structure perturbing capability of the polar organic solutes is a controlling factor in the permeation mechanism at relatively low temperature, where P(HEMA) membrane has higher water content and more structured water. In addition, it is found that the poor separation for urea of cellulose acetate membrane in the reverse osmosis practice is due to the higher water structure-breaking capability of urea. 相似文献
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Cognitive radios such as intelligent phones and Bluetooth devices have been considered essential goods in next-generation communication systems.Such devices will have to share the same frequency band owing to the limited bandwidth resource.To improve spectrum efciency,we formulate multi-channel power allocation as a market competitive equilibrium(CE)problem,and prove that its solution exists and is unique under the condition of weak interference.We then propose two distributed power allocation algorithms achieving CE,namely the fast convergent power allocation algorithm(FCPAA)and the social-fairness-aware FCPAA(SFAF).Theoretical analysis and simulation results demonstrate that the proposed algorithms lead to better system performance in terms of the guaranteed interference temperature constraint using the price mechanism instead of a strategy based on the Nash equilibrium.Moreover,it is shown that the FCPAA maximizes total utility,and converges more quickly than the method addressed in prior research with the help of improved round-robin rules.However,the FCPAA cannot ensure the same social fairness among secondary users as the SFAF scheme in both the non-fading channel and Rayleigh fading channel;the SFAF balances the individual utility by adjusting each user’s budget at the expense of a small quantity of system total throughput. 相似文献
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Muñoz-Ramírez David-Octavio García-Salgado Beatriz-Paulina Ponomaryov Volodymyr Reyes-Reyes Rogelio Sadovnychiy Sergiy Cruz-Ramos Clara 《Multimedia Tools and Applications》2021,80(9):13707-13734
Multimedia Tools and Applications - The copyright protection of three-dimensional (3D) content is a matter of interest in artistic and creative works due to the rights of the holder for the... 相似文献