Zhu Yi-sheng

Prediction of Protein Coding Regions by Support Vector Machine

With the exponential growth of genomic sequences, there is an increasing demand to accurately identify protein coding regions from genomic sequences. Despite many progresses being made in the identification of protein coding regions by computational methods during recent years, the performances and efficiencies of the prediction methods still need to be improved. A novel method to predict the position of coding regions is proposed. First, a support vector machine is used as a classifier to recognize the first nucleotide of a codon in a coding region. Then, according to the difference of the time frequency characteristics of the output values of the classifier analyzed by Short Time Fourier Transform, the position of coding regions can be accurately determinate. The algorithm is not only can predict coding regions, but also can identify the first nucleotide of the codon in coding regions. This is very significant for accurate translation into a protein sequence. The simulation results show the proposed method is more effective for coding regions prediction than the existing coding region discovery tools.

Research on the electromagnetic radiation of a PCB planar inductor

In this paper, the electromagnetic radiations of a PCB planar inductor are researched based on the antenna theory. For the far-field radiation, each turn in the spiral windings of a PCB planar inductor can be viewed as a loop antenna. According to the antenna theory, it is a small loop antenna in the frequency range of 30MHz to 300MHz. By this assumption, the radiation power of a PCB planar inductor is estimated and found to be negligible. Furthermore, by comparing the radiation resistance of a small loop antenna with it of a short electric dipole, show that the radiation power of a turn in the spiral windings of a PCB planar inductor is far smaller than a copper track with the same dimensions in the printed circuit board. The near-field coupling is discussed based on a simple resonant electric circuit with a PCB planar inductor. The 3D plot of near-field radiation intensity is given, by which illustrate that the near-field coupling is only occur in the area where the inductor is located.

Predicting Splice Site by Improved Bayesian Classifier

Due to the enormous amount of DNA sequences to be processed, the computational speed is an important issue to be considered. Although relatively high accuracy has been achieved by existing methods, most of these prediction methods are computationally intensive. In this paper, a novel method for predicting DNA splice sites using improved bayesian classifier is presented. Naïve bayesian classifier is a simple and effective classification method. Combined with least square, the dependence among attributes which assumed to be independent originally can be expressed using linear function. This improves the classification performance. The simulation results show the computation time is linear to the number of sequences tested, while the performance is notably improved compared with the naïve bayesian classifier. The classification results of the proposed method are also comparable to the solution quality obtained by the existing discovery tools, while the speed of the proposed method is significantly faster. This is a notable improvement in computational modeling considering the huge amount of DNA sequences to be processed.

Analysis of electromagnetic scattering from a PCB inductor based on wavelet-Mom

Inductor is a very popular device in various circuits. A PCB (printed circuit board) inductor makes its size more compact. When the signal frequency reaches to radio or microwave bands the radiation and scattering from it must be considered. Electromagnetic scattering from a PCB inductor is studied in this paper. Combining Mom with wavelet analysis sparsifies the matrix produced in calculation, which decreases calculation time and saves the computer sources. A Coifman intervallic scarlet on [0, 1] with level 6 is constructed for evaluating the current distribution on the PCB inductor wire. The current distribution and radiation pattern of a circular PCB inductor are given finally.

Adaptive biorthogonal local discrete cosine transform for interference excision in direct sequence spread spectrum communications

A novel time-frequency domain interference excision technique is proposed. The technique is based on adaptive biorthogonal local discrete cosine transform (BLDCT). It uses a redundant library of biorthogonal local discrete cosine bases and an efficient concave cost function to match the transform basis to the interfering signal. The main advantage of the algorithm over conventional transform domain excision algorithms is that the basis functions are not fixed but can be adapted to the time-frequency structure of the interfering signal. It is well suited to transform domain compression and suppression of various types of interference. Compared to the discrete wavelet transform (DWT) that provides logarithmic division of the frequency bands, the adaptive BLDCT can provide more flexible frequency resolution. Thus it is more insensitive to variations of jamming frequency. Simulation results demonstrate the improved bit error rate (BER) performance and the increased robustness of the receiver.

The structure and analysis of coreless printed circuit board transformers

The coreless printed circuit board (PCB) transformers have good characteristics at high-frequency. They have the advantages of low costs, very high power density, no magnetic loss. Their structures are simple and easy to be integrated for manufactures. This paper introduces the structure of the coreless PCB transformers; especially an improved calculation of the self and mutual impedances in coreless PCB transformers is given. An experiment proved that the theory calculation is closely coincident with the testing results.

A fast parameter estimation registration algorithm for data fusion

A fast parameter estimation registration algorithm is developed to accurately estimate and correct the systematic errors of a data fusion system. The registration problem is expressed by a maximum-likelihood criterion function of the sensor measurements. The criterion function is optimized by a fast Newton algorithm. The effectiveness of the proposed algorithm is confirmed by simulation.