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41.
In this paper, a novel system has been developed for plasma disruption conditions followed by downward vertical displacement. During the disruption, size and orientation of plasma decreases, which gives the halo current circulated around each contacting point in radial as well as in poloidal directions. Therefore, a new mathematical model has been developed, which gives the interaction forces of halo current, vertical, and radial plasma dynamical behavior (linear and nonlinear). This theoretical approach showed that the tokamak plasma has two connecting points in order to distinguish between the stable and unstable position. This model can particularly give the magnetic field change points and changing of flux, which are more convenient in order to discuss the static and tilting position of plasma behavior. Numerical techniques have been calculated in terms of plasma dynamical behavior, that is, Electromagnetic/plasma, Vertical Displacement Event (VDE) stages, and initial interaction between the forces under specific time interval. The objective of the research is to developed theoretical and computational model in order to investigate the dynamical behavior of plasma under disruption conditions. This is the novel method, and no work has been reported so far. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
42.
本文简单介绍了浮筒液位计的分类、测量原理及安装规范,对其各种测量误差的来源作出了详细的分析,并针对各种测量误差的特性,指出了它们的作用方式、影响范围及程度,在此基础上提出相应的抑制及消除方法。 相似文献
43.
In many-objective optimization, the balance between convergence and diversity is hard to maintain, while the dominance resistant solutions (DRSs) could further harm the balance particularly in high-dimensional objective space. Thus, this paper proposes a novel selection strategy – boundary elimination selection based on binary search (called BESBS), trying to avoid the impact of DRSs during the optimization and achieve a good balance between the convergence and diversity simultaneously. During the environmental selection, the binary search (BS) is used to adaptively adjust the ϵ value in the ϵ-dominance relationship and assist in detecting the well-distributed neighbors for the elite solutions. Then the ϵ value obtained by BS is used for serving the boundary elimination selection (BES) to guarantee the stability of the elite population. To improve the convergence, BES is mainly designed to select individuals approximating to the ideal point. By modifying the fitness of solutions and choosing solutions in terms of the shuffled sequence of objective axis, the DRSs will be eliminated during the selection. Thus, BESBS could achieve a good balance between the convergence and diversity and avoid the impact from DRSs simultaneously. From a series of experiments with 35 instances, the experimental results have shown that BESBS is competitive against 8 state-of-art many-objective evolutionary algorithms. 相似文献
44.
Bertha Guijarro-Berdiñas Elena Hernández-PereiraDiego Peteiro-Barral 《Expert systems with applications》2012,39(8):7084-7092
This paper presents a novel approach for classifying sleep apneas into one of the three basic types: obstructive, central and mixed. The goal is to overcome the problems encountered in previous work and improve classification accuracy. The proposed model uses a new classification approach based on the characteristics that each type of apnea presents in different segments of the signal. The model is based on the error correcting output code and it is formed by a combination of artificial neural networks experts where their inputs are the coefficients obtained by a discrete wavelet decomposition applied to the raw samples of the apnea in the thoracic effort signal. The input coefficients received for each network were determined by a feature selection method (support vector machine recursive feature elimination). In order to train and test the systems, 120 events from six different patients were used. The true error rate was estimated using a 10-fold cross validation. The results presented in this work were averaged over 10 different simulations and a multiple comparison procedure was used for model selection. The mean test accuracy obtained was 90.27% ± 0.79, and the values for each class apnea were 94.62% (obstructive), 95.47% (central) and 90.45% (mixed). Up to the authors’ knowledge, the proposed classifier surpasses all previous results. 相似文献
45.
Resveratrol has been reported to show various beneficial pharmacological effects. Nowadays, resveratrol dietary supplement (RDS) is available in the market. Cyclosporin (CsA), a probe drug of P-glycoprotein (P-gp) and cytochrome P450 3A4 (CYP3A4), is an important immunosuppressant. This study investigated the effect of coadministration of RDS on CsA pharmacokinetics. 相似文献
46.
弱膨胀性泥岩地区小型引水隧洞病害分析及加固 总被引:1,自引:0,他引:1
以贵州某水电站无压引水隧洞加固工程为例,针对弱膨胀性泥岩导致的隧洞侧墙变形开裂、顶拱岩块脱落、底板隆起等工程病害,结合工程所在区域的地质特点,通过试验和地质雷达等手段对隧洞围岩变形特征进行分析,明确了隧道围岩长期遭水浸泡,膨胀性围岩遇水膨胀是引发隧洞病害的主要诱因。采用三维数值模型,对隧洞膨胀性围岩遇水膨胀导致的隧洞侧墙应力应变分布特征进行模拟。拟定以排水、隔水为主,同时采用锚杆加固、对侧墙变形严重区段分块拆除重建的工程修复方案,并提出在实际施工过程中应注意隧洞侧墙逆止阀安装、隧洞侧墙拆除重建等施工工艺要求。本隧洞修复工程最终取得良好的实际运用效果。 相似文献
47.
Sliding mode control (SMC) is emerged as a powerful robust controller for the process control application. However, it does not posses robustness properties during reaching phase and suffers from chattering, which is undesirable. In this paper, a chatter free discrete sliding mode controller (DSMC) with reaching phase elimination is proposed. The issue of existence of reaching phase due to physical constraints such as saturation of actuating devices is also addressed. The two-input–two-output (TITO) system is decoupled into two single-input–single-output (SISO) systems using ideal decoupler. The DSMCs are separately designed for two decoupled SISO systems. The stability is ensured via Lyapunov approach. Simulation study and experimentation on real life interacting two tank liquid level system are included to demonstrate effectiveness and applicability of the proposed controller. 相似文献
48.
以3,3,3-三氟丙烯和溴为原料,经加成反应合成了中间产物1,2-二溴-3,3,3-三氟丙烷,随后在氢氧化钠水溶液中进行消除反应制备了目标产物2-溴-3,3,3-三氟丙烯,通过试验得到了较佳的反应条件。 相似文献
49.
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