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NEW HYBRID ALGORITHM FOR WEAK RELATIVELY NONEXPANSIVE MAPPING AND INVERSE-STRONGLY MONOTONE MAPPING IN BANACH SPACE

  • Zhang, Xin;Su, Yongfu;Kang, Jinlong
    • Journal of applied mathematics & informatics
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    • v.29 no.1_2
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    • pp.87-102
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    • 2011
  • The purpose of this paper is to prove strong convergence theorems for finding a common element of the set of fixed points of a weak relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-strongly-monotone mapping by a new hybrid method in a Banach space. We shall give an example which is weak relatively nonexpansive mapping but not relatively nonexpansive mapping in Banach space $l^2$. Our results improve and extend the corresponding results announced by Ying Liu[Ying Liu, Strong convergence theorem for relatively nonexpansive mapping and inverse-strongly-monotone mapping in a Banach space, Appl. Math. Mech. -Engl. Ed. 30(7)(2009), 925-932] and some others.

MONOTONE CQ ALGORITHM FOR WEAK RELATIVELY NONEXPANSIVE MAPPINGS AND MAXIMAL MONOTONE OPERATORS IN BANACH SPACES

  • Kang, Jinlong;Su, Yongfu;Zhang, Xin
    • Journal of applied mathematics & informatics
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    • v.29 no.1_2
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    • pp.293-309
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    • 2011
  • The purpose of this article is to prove strong convergence theorems for weak relatively nonexpansive mapping which is firstly presented in this article. In order to get the strong convergence theorems for weak relatively nonexpansive mapping, the monotone CQ iteration method is presented and is used to approximate the fixed point of weak relatively nonexpansive mapping, therefore this article apply above results to prove the strong convergence theorems of zero point for maximal monotone operators in Banach spaces. Noting that, the CQ iteration method can be used for relatively nonexpansive mapping but it can not be used for weak relatively nonexpansive mapping. However, the monotone CQ method can be used for weak relatively nonexpansive mapping. The results of this paper modify and improve the results of S.Matsushita and W.Takahashi, and some others.

STRONG CONVERGENCE OF MONOTONE CQ ITERATIVE PROCESS FOR ASYMPTOTICALLY STRICT PSEUDO-CONTRACTIVE MAPPINGS

  • Zhang, Hong;Su, Yongfu;Li, Mengqin
    • Journal of applied mathematics & informatics
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    • v.27 no.3_4
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    • pp.763-771
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    • 2009
  • T.H. Kim, H.K. Xu, [Convergence of the modified Mann's iteration method for asymptotically strict pseudo-contractions, Nonlinear Anal.(2007),doi:l0.l016/j.na.2007.02.029.] proved the strong convergence for asymptotically strict pseudo-contractions by the classical CQ iterative method. In this paper, we apply the monotone CQ iterative method to modify the classical CQ iterative method of T.H. Kim, H.K. Xu, and to obtain the strong convergence theorems for asymptotically strict pseudo-contractions. In the proved process of this paper, Cauchy sequences method is used, so we complete the proof without using the demi-closedness principle, Opial's condition or others about weak topological technologies. In addition, we use a ingenious technology to avoid defining that F(T) is bounded. On the other hand, we relax the restriction on the control sequence of iterative scheme.

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Signaling Pathways Controlling Microglia Chemotaxis

  • Fan, Yang;Xie, Lirui;Chung, Chang Y.
    • Molecules and Cells
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    • v.40 no.3
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    • pp.163-168
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    • 2017
  • Microglia are the primary resident immune cells of the central nervous system (CNS). They are the first line of defense of the brain's innate immune response against infection, injury, and diseases. Microglia respond to extracellular signals and engulf unwanted neuronal debris by phagocytosis, thereby maintaining normal cellular homeostasis in the CNS. Pathological stimuli such as neuronal injury induce transformation and activation of resting microglia with ramified morphology into a motile amoeboid form and activated microglia chemotax toward lesion site. This review outlines the current research on microglial activation and chemotaxis.

Probabilistic Load Flow for Power Systems with Wind Power Considering the Multi-time Scale Dispatching Strategy

  • Qin, Chao;Yu, Yixin;Zeng, Yuan
    • Journal of Electrical Engineering and Technology
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    • v.13 no.4
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    • pp.1494-1503
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    • 2018
  • This paper proposes a novel probabilistic load flow model for power systems integrated with large-scale wind power, which considers the multi-time scale dispatching features. The ramp limitations of the units and the steady-state security constraints of the network have been comprehensively considered for the entire duration of the study period; thus, the coupling of the system operation states at different time sections has been taken into account. For each time section, the automatic generation control (AGC) strategy is considered, and all variations associated with the wind power and loads are compensated by all AGC units. Cumulants and the Gram-Charlier expansion are used to solve the proposed model. The effectiveness of the proposed method is validated using the modified IEEE RTS 24-bus system and the modified IEEE 118-bus system.

A New Direct Power Control Strategy for NPC Three-Level Voltage Source Rectifiers Using a Novel Vector Influence Table Method

  • Xia, Chang-Liang;Xu, Zhe;Zhao, Jia-Xin
    • Journal of Power Electronics
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    • v.15 no.1
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    • pp.106-115
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    • 2015
  • This paper proposes a novel direct power control (DPC) strategy for neutral-point-clamped (NPC) three-level rectifiers, to directly control the active power, the reactive power and the neutral point potential of the rectifiers by referring to three pre-calculated vector influence tables and minimizing an objective function. In the three vector influence tables, the influences of different voltage vectors on the active power, the reactive power and the neutral-point potential are shown explicitly. A conceptual description and control algorithm of the proposed controller are presented in this paper. Then, numerical simulations and experiments are carried out to validate the proposed method. Both the simulation and experimental results show that good performances during both the steady-state and transient operating conditions are achieved. As a result, the proposed strategy has been proven to be effective for NPC three-level rectifiers.

State-of-charge Estimation for Lithium-ion Battery using a Combined Method

  • Li, Guidan;Peng, Kai;Li, Bin
    • Journal of Power Electronics
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    • v.18 no.1
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    • pp.129-136
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    • 2018
  • An accurate state-of-charge (SOC) estimation ensures the reliable and efficient operation of a lithium-ion battery management system. On the basis of a combined electrochemical model, this study adopts the forgetting factor least squares algorithm to identify battery parameters and eliminate the influence of test conditions. Then, it implements online SOC estimation with high accuracy and low run time by utilizing the low computational complexity of the unscented Kalman filter (UKF) and the rapid convergence of a particle filter (PF). The PF algorithm is adopted to decrease convergence time when the initial error is large; otherwise, the UKF algorithm is used to approximate the actual SOC with low computational complexity. The effect of the number of sampling particles in the PF is also evaluated. Finally, experimental results are used to verify the superiority of the combined method over other individual algorithms.

Strong Convergence Theorems for Asymptotically Nonexpansive Mappings by Hybrid Methods

  • Qin, Xiaolong;Su, Yongfu;Shang, Meijuan
    • Kyungpook Mathematical Journal
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    • v.48 no.1
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    • pp.133-142
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    • 2008
  • In this paper, we prove two strong convergence theorems for asymptotically nonexpansive mappings in Hibert spaces by hybrid methods. Our results extend and improve the recent ones announced by Nakajo, Takahashi [K. Nakajo, W. Takahashi, Strong convergence theorems for nonexpansive mappings and nonexpansive semigroups, J. Math. Anal. Appl. 279 (2003) 372-379], Kim, Xu [T. H. Kim, H. K. Xu, Strong convergence of modified mann iterations for asymptotically nonexpansive mappings and semigroups, Nonlinear Anal. 64 (2006) 1140-1152], Martinez-Yanes, Xu [C. Martinez-Yanes, H. K. Xu, Strong convergence of the CQ method for fixed point iteration processes, Nonlinear Anal. 64 (2006) 2400-2411] and some others.

Research and Stability Analysis of Active-Disturbance-Rejection-Control-Based Microgrid Controllers

  • Xu, Xiaoning;Zhou, Xuesong;Ma, Youjie;Liu, Yiqi
    • Journal of Power Electronics
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    • v.17 no.6
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    • pp.1611-1624
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    • 2017
  • With the rapid development of microgrid technology, microgrid projects are no longer limited to laboratory demonstrations and pilot platforms. It shows greater value in practical applications. Hence, the smooth interaction between a microgrid and the main grid plays a critical role. In this paper, a control method based on active disturbance rejection control (ADRC) is proposed in order to realize seamless transitions between grid-connected and islanding operation modes and stable operation with variable loads. It is verified by simulations that the proposed ADRC-based method features better performance when compared to conventional proportional-integral-differential (PID) control. Meanwhile, the stability of the third-order extended state observer (ESO) in second-order ADRC is validated by using Lyapunov stability criteria.

Mechanical properties of stabilized saline soil as road embankment filling material

  • Li Wei;Shouxi Chai;Pei Wang
    • Geomechanics and Engineering
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    • v.37 no.5
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    • pp.499-510
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    • 2024
  • In northern China, abundant summer rainfall and a higher water table can weaken the soil due to salt heave, collapsibility, and increased moisture absorption, thus the chlorine saline soil (silty clay) needs to be stabilized prior to use in road embankments. To optimize chlorine saline soil stabilizing programs, unconfined compressive strength tests were conducted on soil treated with five different stabilizers before and after soaking, followed by field compaction test and unconfined compressive strength test on a trial road embankment. In situ testing were performed with the stabilized soils in an expressway embankment, and the results demonstrated that the stabilized soil with lime and SH agent (an organic stabilizer composed of modified polyvinyl alcohol and water) is suitable for road embankments. The appropriate addition ratio of stabilized soil is 10% lime and 0.9% SH agent. SH agent wrapped soil particles, filled soil pores, and generated a silk-like web to improve the moisture stability, strength, and stress-strain performance of stabilized soil.