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Abstract [Objective] The study aims to examine the characteristics of innate immune physiological responses induced by chitin and flagellin-derived peptide flg22 in pepper seedlings, and to explore the relationship between innate immune physiological responses and pepper multiple resistance to diseases. [Methods] Five local pepper cultivars from Sichuan were used as experimental materials. The disease indexes of bacterial wilt and phytophthora blight in pepper seedlings were analyzed. Seedlings were cultured by hydroponics and treated with chitin and flg22 exogenously. Root growth, stomata aperture, callose deposition, reactive oxygen species (ROS) accumulation, SOD, CAT activities as well as gene expression under different induction times were analyzed. The physiological responses and their relationship with disease resistance were evaluated comprehensively using biostatistics. [Results] (1) The lowest disease index of bacterial wilt and phytophthora blight was ‘Chuanteng No.10’ (‘CT10’) cultivar, which was the strongest in disease resistance. The highest disease index of bacterial wilt and phytophthora blight was ‘Tiaojiao’ (‘TJ’) cultivar, which was the weakest in disease resistance. (2) Exogenous chitin and flg22 inhibited the root growth rate of pepper seedlings in five cultivars, induced stomatal closure on detached leaves, promoted callose deposition in cell wall, and increased ROS levels with improved SOD and CAT activities. By calculating the average membership function value of the innate immune physiological response, it showed that the highest was ‘CT10’ and the lowest was ‘TJ’. The average membership function value has a significant negative correlation with the disease index of bacterial wilt and phytophthora blight. (3) flg22 and chitin induced the expression of genes involved in innate immune response in ‘CT10’, such as CaWRKY22, CaMAPK7, and ChiIV3. [Conclusion] Exogenous flg22 and chitin induce the innate immune physiological responses in pepper seedlings, with variations among the varieties. The average membership function of ‘CT10’ is the highest and the multi-resistance level is the best, due to the up-regulated expression of CaWRKY22, CaMAPK7, and ChiIV3.

Vertical alignment reconstruction obtains alignment parameters by fitting geometric components to a set of measured points representing the profile of an existing road or railroad, which is essential in alignment consistency analysis and maintenance to ensure safety and comfort. The neural dynamics model of Adeli and Park is explored and improved for reconstructing vertical alignments with constraints. The structure of the dynamics model is modified to include three layers: parameter layer, intermediate layer, and energy layer. The number of nodes in the parameter or intermediate layers corresponds to the number of independent parameters defining a vertical alignment. The number of nodes in the energy layer is the sum of the number of deviations and the number of constraints in the alignment reconstruction problem. The coefficients connecting nodes between the parameter layer and the intermediate layer determine the integral operations, which define the Levenberg–Marquardt algorithm of the dynamics model (LMADM) and the steepest descent algorithm of the dynamics model (SDADM). Both the LMADM and SDADM methods satisfy the Lyapunov stability theorem, but the LMADM method outperforms the SDADM method in its objective function value and computation time. Experiment results demonstrate that there are multiple local optima for a vertical alignment reconstruction, and the solutions obtained by the LMADM method are the best obtained so far, compared with those reported in the literature, with 57.1% and 23.4% decreases of the mean squared error for the highway and the railroad examples, respectively. [ABSTRACT FROM AUTHOR]

Due to high power-transforming capability and excellent fault-tolerant performance, dual three-phase permanent magnet synchronous machines (DT-PMSMs) are widely used in high-reliability applications. Concerning on the remedial strategy for DT-PMSMs under open-phase faults, the conventional method is to reconfigure the controller or the current references in order to obtain optimum postfault performances. Two different control schemes should be separately designed for normal and fault conditions, respectively. Meanwhile, related fault detection measures need to be adopted and the inherent fault detection delay will further result in transient performance deterioration. In order to solve these problems, this article proposes a control strategy, which can achieve natural fault-tolerant capability of DT-PMSMs without additional fault detection algorithm. With the proposed control method adopted, reconfiguration of the control structure and modification of the current command are not required. Thus, the control scheme is simplified. The transition from the healthy to the postfault operation can be improved, meanwhile, the steady-state performances in prefault and postfault situations can be guaranteed. The proposed strategy can be generally applied to single open-phase faults and multiple open-phase faults in DT-PMSMs. Experimental validations are presented on a 1 kW DT-PMSM platform to prove the effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

Stator and rotor cores of interior permanent magnet (IPM) motors are usually saturated, and the saturation distribution and saturation depth vary with the stator current. Also, their rotor structures are complex; hence, the saturation cannot be accurately reflected by a saturation factor. These considerations lead to the existing equivalent air-gap length models of induction motors and inset permanent magnet (PM) motors no longer suitable for IPM motors. Therefore, based on the consideration of stator and rotor saturation, this article proposes the equivalent air-gap length model of IPM motors expressed by magnetic potentials on the stator inner surface and the rotor outer surface. The proposed equivalent air-gap length model can accurately reflect the influences of complex structure and severe saturation of IPM motors. Compared with the existing models, the proposed one is no longer uniquely determined by motor structure parameters; it is also a function of stator current and rotor position. Furthermore, the obtained equivalent air-gap length model is combined with the winding function and the modified winding function to solve the inductances under different stator currents and different rotor eccentricity states. Finally, the proposed method is verified by both finite element analysis (FEA) and experiments. [ABSTRACT FROM AUTHOR]

A major problem of vertical alignment recreation is to automatically attribute the measured points to geometric elements (i.e., grades and vertical curves) and to efficiently recreate the vertical alignment with constraints. Most existing methods are nonoptimal in theory, semiautomatic, or inefficient in recreating an alignment. A new approach is proposed for automatically determining segmentation into geometric elements from measured points and efficiently optimizing a recreated alignment with constraints. First, independent parameters defining an alignment, are proposed to represent a vertical alignment. Then, a statistical deflection angle (SDA) method is proposed to determine segmentation by exploring statistical features of the geometric elements. Analysis shows that the SDA method outperforms the curvature method in distinguishing between grades and curves. Patterns of the segmentation process are found, and a segmentation algorithm is provided. Further, an optimization model is proposed to recreate the alignment with constraints. Experiment results demonstrate that this approach is highly efficient and effective compared with existing methods, reducing the number of searched alignments from tens of thousands to tens, while improving the value of the objective function. [ABSTRACT FROM AUTHOR]