Model tests on anomalous low friction and pendulum-type wave phenomena

The anomalous low friction (ALF) and pendulum-type wave (μwave) phenomena were two typical,nonlinear,geo-mechanical,and dynamic responses in deep-block rock mass discovered from in situ observations,which occurred from the movement of the geo-blocks under the impact of external pulses,such as deep confined explosion,earthquake,and rock bursts.With the aim to confirm the existence of the above two phenomena and study the variation laws of them experimentally,laboratory tests on the granite and cement mortar continuum and blocks models were conducted on the self-independently developed multipurpose testing system,respectively.The ALF phenomenon was realized under two loading schemes,the blocks model and working block were acted upon by the joint action of vertical impact and horizontal static force as well as the joint action of both vertical and horizontal impacts with different time intervals.It revealed that the discrete time delays corresponding to the local maximums and minimums of the horizontal displacement amplitudes and residual horizontal displacements of the working block satisfied the canonical sequences with the multiple of √2,most of which satisfied the quantitative expression (√2)~i △/V_p.Besides,the one-dimensional impact experiments were carried out on the blocks granite model,continuum,and blocks cement mortar models,respectively.Based on the comparison and analysis of the propagation properties (amplitudes and the Fourier spectrums of acceleration time histories of blocks) of the 1D stress wave in the above models,it is indicated that the fractures in rock mass have tremendous effect on the attenuation of acceleration amplitudes and high-frequency waves.By comparison of the model test data with the in situ measurement conclusions,the existence of the μ wave was confirmed experimentally in the cement mortar blocks model with larger dimensions,and the frequencies corresponding to the local maximums of spectral density curves of three-directional acceleration time histories of sub-blocks also satisfied several canonical sequences with the multiple of √2.     

成都麻羊MyoG基因的克隆与测序分析

根据猪MyoG基因的部分序列和绵羊MyoG mRNA设计引物,以成都麻羊、金堂黑山羊、白玉黑山羊和高原型藏山羊基因组为模板,应用PCR技术克隆测定MyoG基因序列．序列分析结果表明,成都麻羊MyoG基因长1957bp,由3个外显子和2个内含子组成,其中外显子Ⅰ、Ⅱ、Ⅲ的大小分别为398bp、82bp、122bp．内含子Ⅰ和内含子Ⅱ的大小分别为765bp和589bp．成都麻羊MyoG基因序列与金堂黑山羊、白玉黑山羊和高原型藏山羊的MyoG基因序列进行比对,同源性分别为99．9％、99．7％和99．3％,而它们氨基酸序列的同源性都为100％．这为进一步研究成都麻羊MyoG基因的表达、生物学活性和应用奠定了一定基础．     

Strong stability of linear forms in φ -mixing random variables

In this paper some new results of strong stability of linear forms in φ-mixing random variables are given. It is mainly proved that for a sequence of φ-mixing random variables {x _n , n ⩾ 1} and two sequences of positive numbers {a _n , n ⩾ 1} and {b _n , n ⩾ 1} there exist d _n ∈ R, n = 1,2,L, such that a.s. under some suitable conditions. The results extend and improve the corresponding theorems for independent identically distributed random variables. Foundation item: Supported by the National Natural Science Foundation of China(10671149)     

屏蔽二进序列偶的唯一性问题研究

提出并证明了几乎最佳屏蔽二进序列偶的唯一性问题,并将最佳屏蔽二进序列偶作为特例证明其也满足唯一性.此外,还提出并证明了伪随机屏蔽二进序列偶的唯一性问题,从理论上保证了上述信号在应用时的唯一接收.     

Pell方程x^2-（a^2-1）y^2=k的解集

应用本原解、解数列等概念,完整、清晰地表述了形如x^2-（a^2-1）y^2=k（k∈Z,k≠0,a≥2）型Pell方程的整数解集.     

由鞅差序列生成的线性过程的Baum-Katz大数定律的精确渐近性

主要讨论了线性过程Xt=∑∞j=0ajεt-j,其中{εt,Ft;t∈Ζ}是均值为零,方差有限的平稳鞅差序列,aj,j∈Ζ是绝对可和的实数序列.令Sn=∑nt=1Xt,n≥1,在适当矩的条件下,利用部分和Sn的收敛性,对于1≤p2,若supj≥1Eεjδ＆lt;∞,证明了∑∞n=1nr/p-2P｜Sn｜≥εn1p,∑∞n=1n-1/P｜Sn｜≥εn1/p当ε→0时的精确渐进性.在鞅差序列的前提下,进一步推广了线性过程的Baum-Katz大数律的精确渐近性性质.     

一种降低OFDM系统峰均比的PTS-TR联合算法

提出一种部分传输序列（partial transmit sequence, PTS）算法与载波预留法（tonereservation）相结合的算法来降低OFDM系统峰均功率比（peak-to-average power ratio,PAPR）,传统的PTS算法可以在不使信号失真的情况下很好地降低高PAPR出现的概率,但是这种算法的缺点是计算量过大,而TR法虽有不用传递边带信息的优点,但当预留子载波取值小时会得不到理想的性能,取值过大又会浪费系统功率,联合算法在大大地降低了PTS计算量、TR预留载波取值小的同时,还保持了良好的PAPR性能,仿真结果验证了其有效性。     

Low complexity method for spreading sequence estimation of DSSS signal in non-cooperative communication systems

It is a necessary step to estimate the spreading sequence of direct sequence spread spectrum (DSSS) signal for blind despreading and demodulation in non-cooperative communications. Two innovative and effective detection statistics axe proposed to implement the synchronization and spreading sequence estimation procedure. The proposed algorithm also has a low computational complexity with only linear additions and modifications. Theoretical analysis and simulation results show that the algorithm performs quite well in low SNR environment, and is much better than all the existing typical algorithms with a comprehensive consideration both in performance and computational complexity.     

赋范线性空间中一致L-Lipschitz映射的不动点迭代逼近

研究了赋范线性空间中一致L-Lipschitz映射和渐近非扩张映射不动点的迭代逼近问题,并改进和推广了文献[1]中的主要结果。