行和、列和始元幻阵的构造方法

将行和、列和幻阵A_(m×n)按m和n的奇偶性分成四种类型,分别为m=2l+1,n=2k+1;m=2l+1,n=2k;m=2l,n=2k+1和m=2l,n=2k,并对这些类型分别给出相应的构造方法.

Isolation and Chromosomal Mapping of a Corn B Chromosome Specific RAPDs

B染色体存在于多种动植物中 ,具有很多独特的性状。B染色体与正常染色体在DNA组成方面十分相似 ,寻找B染色体特异序列一直是B染色体研究的难点和热点。通过对含有和不含有B染色体的两种玉米 (ZeamaysL .)基因组进行了RAPD分析 ,筛选到一个B染色体特异性分子标记B480。该标记与玉米的自主复制起始序列ARS1和ARS2同源 ,特别是该序列中的 2 5bp出现在多种模式生物基因组中。FISH的结果显示 。

Effects of Freezing Disaster on Green-up Date of Vegetation Using MODIS/EVI Time Series Data

In the field of global changes, the relationship between plant phenology and climate, which reflects the response of terrestrial ecosystem to global climate change, has become a key subject that is highly concerned. Using the moderate-resolution imaging spectroradiometer (MODIS)/enhanced vegetation index(EVI) collected every eight days during January- July from 2005 to 2008 and the corresponding remote sensing data as experimental materials, we constructed cloud-free images via the Harmonic analysis of time series (HANTS). The cloud-free images were then treated by dynamic threshold method for obtaining the vegetation phenology in green up period and its distribution pattern. And the distribution pattern between freezing disaster year and normal year were comparatively analyzed for revealing the effect of freezing disaster on vegetation phenology in experimental plot. The result showed that the treated EVI data performed well in monitoring the effect of freezing disaster on vegetation phenology, accurately reflecting the regions suffered from freezing disaster. This result suggests that processing of remote sensing data using HANTS method could well monitor the ecological characteristics of vegetation.

Comparison of robust H_∞ filter and Kalman filter for initial alignment of inertial navigation system

There are many filtering methods that can be used for the initial alignment of an integrated inertial navigation system. This paper discussed the use of GPS, but focused on two kinds of filters for the initial alignment of an integrated strapdown inertial navigation system (SINS). One method is based on the Kalman filter (KF), and the other is based on the robust filter. Simulation results showed that the filter provides a quick transient response and a little more accurate estimate than KF, given substantial process noise or unknown noise statistics. So the robust filter is an effective and useful method for initial alignment of SINS. This research should make the use of SINS more popular, and is also a step for further research.

Instability and Death of Spiral Wave in a Two-Dimensional Array of Hindmarsh-Rose Neurons

Spiral wave could be observed in the excitable media, the neurons are often excitable within appropriateparameters. The appearance and formation of spiral wave in the cardiac tissue is linked to monomorphic ventriculartachycardia that can denervate into polymorphic tachycardia and ventricular fibrillation. The neuronal system oftenconsists of a large number of neurons with complex connections. In this paper, we theoretically study the transitionfrom spiral wave to spiral turbulence and homogeneous state (death of spiral wave) in two-dimensional array of theHindmarsh-Rose neuron with completely nearest-neighbor connections. In our numerical studies, a stable rotating spiralwave is developed and selected as the initial state, then the bifurcation parameters are changed to different values toobserve the transition from spiral wave to homogeneous state, breakup of spiral wave and weak change of spiral wave,respectively. A statistical factor of synchronization is defined with the mean field theory to analyze the transition fromspiral wave to other spatial states, and the snapshots of the membrane potentials of all neurons and time series of meanmembrane potentials of all neurons are also plotted to discuss the change of spiral wave. It is found that the sharpchanging points in the curve for factor of synchronization vs. bifurcation parameter indicate sudden transition fromspiral wave to other states. And the results are independent of the number of neurons we used.

Fired Models of Air-gun Source and Its Application

Air-gun is an important active seismic source.With the development of the theory about air-gun array,the technique for air-gun array design becomes mature and is widely used in petroleum exploration and geophysics.In order to adapt it to different research domains,different combination and fired models are needed.At the present time,there are two fired models of air-gun source,namely,reinforced initial pulse and reinforced first bubble pulse.The fired time,space between single guns,frequency and resolution of the two models are different.This comparison can supply the basis for its extensive application.

Interactions of Two Identical Wave Trains with a Relative Separation Angle of 24?

Interactions between two identical monochromatic wave trains with a relative separation angle of 24? were experimentally investigated in a well-designed ‘X' configuration.Wave trains with different amplitudes and frequencies were generated.The results demonstrated that the interaction was strongly dependent on both wave amplitude and frequency.For nonbreaking and lower-frequency cases,the wave trains can approximately reestablish their initial state following the interaction.However,for larger waves,the interaction was enhanced,distorting the surfaces significantly-the wave trains were no longer two-dimensional after the encounter.During the interaction process,there was an obvious increase in wave height,reaching a maximum amplification in the middle of the interaction region that was approximately 1.55 times the initial height.Furthermore,the images captured by high-speed cameras illustrated that two wave trains entered the interaction region at the same time and then merged during the interaction process,resulting in an increase in wave amplitude.The combined wave crest was initially composed of two straight segments with a relative angle of 24? and gradually morphed into a single segment as is evident in the plan view.The wave then broke in the downstream,still within the interaction region,exhibiting a crescent pattern along the crest.

Energy Transfer among Modes in a Non-Slender Elastic Beam Subject to Vortex-Induced Vibration

The vibration of an elastic beam experiencing vortex-induced vibration is numerically analyzed employing a wake-oscillator model. The influence of the excited mode, the initial velocity, the shedding pulsation and the mass ratio on the energy transfer among modes and the vibration amplitude is determined. Multiple frequencies are detected, and the power spectral density of the beam tip time series is used to calculate the dominant frequency.

论传统和弦与现代和音的中介——兼论全音程四音集合与变五音和弦的中介特征

在传统和弦与现代和音之间,存在着一个极为明显的的中间环节,此中间环节即本文所称的中介。在这里,中介表现为传统和弦向现代和音转化的中间阶段。如果说,传统和弦与现代和音有着迥然不同的特点,那么,两者的对立有可能在中介环节中得以“钝化”或融合。过去被人们认为是互不相干的传统和弦与现代和音,实际上正通过它们的中介而互相联系起来。现代和声研究将在这里预示着某种一体化的趋向。

Numerical study of the flowing sequence of a pouring liquid

Liquid flows in a particular sequence when it is poured out from an open-top receptacle. Since the sequence is hard to catch by experiment, a numerical simulation was performed in this pouring process with the moving particle semi-implicit (MPS) method. A modified solid-liquid boundary condition was verified and employed with a new definition of static liquid layers. The whole system was discretized by a set of particles and the liquid particles were marked and tracked in the pouring process. The flowing sequence of the liquid can be calculated by restoring the liquid particles back to their initial positions before it is poured. The mass transfer property is found to depend on the position of the rotation axis and the rotation speed, as well as the viscosity of the liquid. The mechanism of the flowing sequence results from a temporal vortex and its motion during the process. The character vortex is generated by the rotation of the container. The results reveal a principle for a versatile pouring process and may contribute to the applications in flowing control in many fields.

Orbit determination using incremental phase and TDOA of X-ray pulsar

X-ray pulsars offer stable, periodic X-ray pulse sequences that can be used in spacecraft positioning systems. A method using X-ray pulsars to determine the initial orbit of a satellite is presented in this paper. This method suggests only one detector to be equipped on the satellite and assumes that the detector observes three pulsars in turn. To improve the performance, the use of incremental phase in one observation duration is proposed, and the incremental phase is combined with the time difference of arrival(TDOA). Then, a weighted least squares(WLS) algorithm is formulated to calculate the initial orbit. Numerical simulations are performed to assess the proposed orbit determination method.

Effective kernel FCM： Finding appropriate structure in cancer database

Finding available subclasses in high-dimensional medical databases using clustering techniques is considered as very important one in medical field. Due to similar intensi- ties between the datapoints in high-dimensionality cancer medical database clustering techniques have failed to cluster the available subclasses with less error. Therefore this paper presents suitable fuzzy-based clustering techniques to find available subclasses in high-dimensional prostate and breast cancer databases. In addition this paper presents prototype initialization algorithm to avoid random initialization of initial prototypes. In order to evaluate the performance of proposed clustering techniques experimental study has been performed on benchmark databases. Finally the proposed methods have been successfully implemented to find the subclasses of cancers in prostate and breast cancer databases. The clustering results of proposed methods have been validated by evaluating clustering accuracy.