Point-to-point and collision avoidance control of the motion of an autonomous bicycle

This work deals with the stabilization and collision avoidance control of a riderless bicycle (see Figure 1). It is assumed here that the bicycle is controlled by a pedalling torque, a directional torque, and by a rotor mounted on the crossbar that generates a tilting torque.Given two points r_A, r_B, and a circular obstacle in the horizontal plane. Also, given a time interval [0, t_f], where 0 < t_f < ∞. It is shown here that by applying a kind of inverse dynamics control, the motion of the bicycle is stabilized while simultaneously controlling its speed and direction in such a manner that the point of contact between the bicycle's rear wheel and the horizontal plane will be able, during [0, t_f], to move from r_A to r_B without hitting the obstacle.     

Slope stability analyses on a low-cost microcomputer

A slope stability program for use on a low-cost microcomputer is described. The program is general in that it includes circular and noncircular slip surface analyses, different soil strata, a watertable, and external loading. The graphics facilities available on the machine are used extensively to produce an interactive program which is easy to understand and run.     

Application of the chebyshev-fourier pseudospectral method to the eigenvalue analysis of circular mindlin plates with free boundary conditions

An eigenvalue analysis of the circular Mindlin plates with free boundary conditions is presented. The analysis is based on the Chebyshev-Fourier pseudospectral method. Even though the eigenvalues of lower vibration modes tend to convergence more slowly than those of higher vibration modes, the eigenvalues converge for sufficiently fine pseudospectral grid resolutions. The eigenvalues of the axisymmetric modes are computed separately. Numerical results are provided for different grid resolutions and for different thickness-to-radius ratios.     

An analytic solution for a fault tree with circular logics in which the systems are linearly interrelated

A circular logic or a logical loop is defined as the infinite circulation of supporting relations due to their mutual dependencies among the systems in the fault tree analysis. While many methods to break the circular logic have been developed and used in the fault tree quantification codes, the general solution for a circular logic is not generally known as yet. This paper presents an analytic solution for circular logics in which the systems are linearly interrelated with each other. To formulate the analytic solution, the relations among systems in the fault tree structure are described by the Boolean equations. The solution is, then, obtained from the successive substitutions of the Boolean equations, which is equivalent to the attaching processes of interrelated system's fault tree to a given fault tree. The solution for three interrelated systems and their independent fault tree structures are given as an example.     

Delamination in elastic shear deformable circular layers

This work extends the analytical solution of an interface crack in straight layered structures to circular layered structures. A small segment at the vicinity of an interface crack tip in a circular laminated beam is analyzed by a novel shear deformable bi-layered circular beam theory. Two concentrated forces are found existing at the crack tip due to the requirement of the equilibrium condition. Closed-form solution of the total energy release rate of the interface crack is obtained as the half of the product of the concentrated forces and the corresponding displacement gradient discontinuities at the crack tip. Closed-form expressions of the mode I and II components of the energy release rate are also obtained by global and local methods. Numerical verifications are conducted by analyzing the interlaminar delamination of a circular beam with an edged crack and comparing with the baseline results obtained through finite element analysis. Excellent agreements between the present method and finite element analysis on the predictions of total energy release rate and mode partition verify the accuracy and efficiency of the present solution.     

改进的基因拷贝数变异检测算法

cnvPartition算法在单核苷酸多态性数据上运算时间复杂度较高。为此,提出一种改进的基因拷贝数变异(CNV)检测算法。将二元分割与cnvPartition算法相结合,优先查找显著变异断点,再检测出隐藏性变异断点。实验结果表明,该算法在位点数增加时,最高可提高50%的检测速度,利于检测出小片段的CNV变异。     

Surface charge and conformational properties of phaseolin,the major globulin in red kidney bean (Phaseolus vulgaris L): effect of pH

The aim of this investigation was to explore the pH‐induced conformational changes of phaseolin using differential scanning calorimetry (DSC), fluorescence and circular dichroism (CD) spectra. The surface charges at the varying pH and ionic strength were also determined to probe the possible relationship between the surface charges of phaseolin and its conformation. The ζ‐potential of phaseolin decreased from 27.9 mV at pH 3.0 to –44 mV at pH 9.4, and the isoelectric point (iep) occurred at pH 4.21, which were comparable with the theoretical estimations derived from amino acid composition and pK values. The iep of phaseolin was independent of ionic strength, while the magnitude of ζ‐potential decreased as the ionic strength increased. The near‐UV CD, DSC and fluorescence spectra analyses indicated highly acidic and alkaline pH conditions induced the loss of tertiary conformation of phaseolin. The far‐UV CD spectra analysis confirmed pH‐shift led to the decreases in ordered secondary structure compositions. The present results suggested the loss of secondary and/or tertiary conformation of phaseolin as a result of the varying pattern in electrostatic interactions as pH shifted from 7.0 to acidic or alkalic pH.     

On the convergence condition of generalized root iterations for the inclusion of polynomial zeros

Using a fixed point relation based on the logarithmic derivative of the k-th order of an algebraic polynomial and the definition of the k-th root of a disk, a family of interval methods for the simultaneous inclusion of complex zeros in circular complex arithmetic was established by Petković [M.S. Petković, On a generalization of the root iterations for polynomial complex zeros in circular interval arithmetic, Computing 27 (1981) 37–55]. In this paper we give computationally verifiable initial conditions that guarantee the convergence of this parallel family of inclusion methods. These conditions are significantly relaxed compared to the previously stated initial conditions presented in literature.     

Using Anfis with circular polygons for impulsive noise suppression from highly distorted images

In this paper, a novel approach is presented to the restoration of images corrupted by impulsive noise (IN), with a new nonlinear IN suppression filter, entitled circular polygons based adaptive-fuzzy filter (CF). The proposed filter is based on statistical impulse detection and nonlinear filtering which uses adaptive-network-based fuzzy inference system (Anfis) as a missed data interpolant over the circular polygons and provides estimates for the original intensity values of corrupted pixels. Impulse detection is realized by using the chi-square based goodness-of-fit test, which yields a decision about the impulsivity of each pixel. Extensive simulations were realized to demonstrate the capability of CF and they reveal that the proposed filter achieves a better performance than the other filters mentioned in this paper in the cases of being effective in noise suppression and detail preservation, also when the images are highly corrupted by IN.