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The highest frequency of interactions was observed in the animals kept in groups in openair cages.


In the frequency matrix of this sequence nucleotides between the 3rd and the 7th position had the highest frequency and guanine nucleotides at the 6th and the 7th positions were recognized in all nucleotide sequences.


The highest frequency of M1plants with chlorophyllic abnormalities (green revertants, lethals, and variegated forms) was observed in nchlorina1 line.


The highest frequency of individuals with the null genotype of both genes was observed in the Kalmyk and Buryat populations.


The highest frequency of abnormal karyotypes (10%) was found among patients with azoospermia and the most frequent anomaly was 47, XXY chromosomal constitution, found in 6 (8.57%) patients.

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 Two new approximate formulas on the natural frequencies ofvibration of MultiDegreeofFreedom linear systems arepresented in this paper.Applying these formulas we can calculateall classes of natural frequencies of the ThreeDegreeofFreedom system.They supplement the Rayligh's and Dunkerley'smethods which only give the upper and lower limit of the fundamental.For the vibration of more than FourDegreeofFreedomsystem,the lower limit of the fundamental and superior limit oftop frequency can be found by... Two new approximate formulas on the natural frequencies ofvibration of MultiDegreeofFreedom linear systems arepresented in this paper.Applying these formulas we can calculateall classes of natural frequencies of the ThreeDegreeofFreedom system.They supplement the Rayligh's and Dunkerley'smethods which only give the upper and lower limit of the fundamental.For the vibration of more than FourDegreeofFreedomsystem,the lower limit of the fundamental and superior limit oftop frequency can be found by thses formulas in this paper.Thelower limit of the fundamental computed by these formulas in thispaper is more precise than that computed by Dunkerley's and issimpler than that computed by Rayleigh's.  本文给出两个计算多自由度线性系统振动固有频率的简便近似公式。对三自由度系统振动,能简便地求出各阶固有频率。弥补了Rayleigh法、Dunkerley法实际上只能给出基频上下限的不足。对四自由度以上的系统振动,也可以求出基频的下限和最高频的上限。而基频下限的精确度始终比Dunkerley法更高,计算过程比Rayleigh法更简便。  An image compression method based on wavelet transform is presented. The image data is discretized by wavelet transform in two dimensions, and then the lowest frequency coefficients are processed using DCT. The DCT coefficients are recorded in zigzag scanning and encoded by run length coding. The highest frequency components are discarded. The higher frequency components are quantized with different quantizers according to human visual characteristics and then VLC is carried out. Simulation results show that... An image compression method based on wavelet transform is presented. The image data is discretized by wavelet transform in two dimensions, and then the lowest frequency coefficients are processed using DCT. The DCT coefficients are recorded in zigzag scanning and encoded by run length coding. The highest frequency components are discarded. The higher frequency components are quantized with different quantizers according to human visual characteristics and then VLC is carried out. Simulation results show that the method proposed is better in both the compression ratio and image quality.  提出了一种基于小波变换的图像压缩方法．先对图像数据进行二维离散小波变换，对变换后的低频系数进行离散余弦变换；再对ＤＣＴ系数进行Ｚ形扫描，游程编码．舍弃最高频系数，对于次高频系数根据人眼的视觉特性采用不同的量化器进行量化，然后进行可变长度编码．实验表明，在图像质量和压缩倍数方面都取得了较好的结果  Through the study of the Embedded Zerotree Wavelet Coding (EZW) algorithm, it is found that this algorithm can not fully utilize the properties of Human Visual System(HVS) to eliminate visual redundancy. An improved image compression algorithm based on bi orthogonal wavelet coefficients is thus presented, mainly including: 1. The subimage of the lowest frequency (LL4) is carried out lossless compressed coding; 2. The subimages on the diagonal direction of the highest frequency(HH1) is abandoned and is not carried... Through the study of the Embedded Zerotree Wavelet Coding (EZW) algorithm, it is found that this algorithm can not fully utilize the properties of Human Visual System(HVS) to eliminate visual redundancy. An improved image compression algorithm based on bi orthogonal wavelet coefficients is thus presented, mainly including: 1. The subimage of the lowest frequency (LL4) is carried out lossless compressed coding; 2. The subimages on the diagonal direction of the highest frequency(HH1) is abandoned and is not carried out coding, because it is of great probability for zero, and it little affects visual. 3. The rest of the subimages are given different bit numbers according to their different characteristics. Then they are carried out quantization of zreotree and run length coding. Experimental results show that this algorithm is more effective.  在对零树编码方法研究的基础上 ,针对零树编码方法没有充分利用HVS特性来有效消除视觉冗余的缺点 ,提出了一种基于小波系数的零树编码方案。其主要包括对最低频子带单独进行无损压缩编码 ,对最高频对角线方向子带舍去不编码 ,对其余各子带根据视觉特点的不同 ,分别分配不同的比特数并按其进行零树量化 ,最后再游程编码。实验表明 ,该方法是一种比较有效的方法。   << 更多相关文摘 
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