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51.
郝伟  刘凤艳 《光散射学报》1999,11(2):96-106
本文简要介绍了计算C G系数的生群元矩阵方程法,给出计算二十面体群C G系数时采用的简化计算方法,并给出了Ⅰ群C G系数的计算结果。  相似文献   
52.
53.
This paper considers the problem of reducing the computational time in testing uniformity for a full period multiple recursive generator (MRG). If a sequence of random numbers generated by a MRG is divided into even number of segments, say 2s, then the multinomial goodness-of-fit tests and the empirical distribution function goodness-of-fit tests calculated from the ith segment are the same as those of the (s + i)th segment. The equivalence properties of the goodness-of-fit test statistics for a MRG and its associated reverse and additive inverse MRGs are also discussed.  相似文献   
54.
We report the development and the characterization of a multipoint parallel excitation and CCD-based imaging system for high-throughput fluorescence detection of biochip micro-arrays. A two-dimensional array of (19×19) points with uniform intensity distribution, generated by a holographic array generator, was used for parallel excitation of two-dimensional micro-arrays of fluorescence samples. A CCD-based imaging system was used for high-throughput parallel detection and quantitative analysis of the fluorescence output. Micro-array samples of cyanine (Cy5) dye dots on silicon wafers and on glass substrates with varying concentration were used to evaluate the performance of the system. Results of fluorescence intensity measurements with varying concentration of dye and with different image acquisition time are presented. We have demonstrated that this novel approach will, in general, outperform the conventional approach in the excitation efficiency, the signal-to-noise ratio, and the throughput. The limitations and the potential improvements of the present method are discussed.  相似文献   
55.
李平  朱士信 《数学杂志》2008,28(2):124-128
本文研究了环F2 uF2上的奇长度的循环码和(1 u)-循环码.运用代数方法,得到了F2 uF2上的循环码和(1 u)-循环码成为自由码的几个充要条件.推广了Bonnecaze(1999)和Aydin(2002)的关于自由码的结果.  相似文献   
56.
对脉冲功率技术驱动的爆聚等离子体过程进行了物理分析,在5%的偏差范围内,得到了和数值计算结果相一致的近似解析公式。计算结果表明,功率在3—4TW,输出电能300—400KJ,技术指标类似PITHON的加速器可以使质量为200—400μg的Kr气爆聚压缩成高温等离子体柱。  相似文献   
57.
A positive‐type photosensitive polyimide (PSPI) based on poly(amic acid) (PAA), a crosslinker 1,1,1‐tris{4‐[2‐(vinyloxy)ethoxy]phenyl}ethane (TVPE), a photoacid generator (PAG) (5‐propylsulfonyloxyimino‐5H‐thiophen‐2‐ylidene)‐2‐(methylphenyl)acetonitrile (PTMA), and a thermobase generator (TBG) t‐butyl 2,6‐dimethylpiperidine‐1‐carboxylate (BDPC) has been developed as a promising material in microelectronics. The PAA was prepared from 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA) and 4,4′‐oxydianiline (ODA) in dimethyl sulfoxide (DMSO). The PSPI, consisting of PAA (69 wt %), TPVE (21 wt %), PTMA (3 wt %), and BDPC (7 wt %), showed high sensitivity of 21 mJ/cm2 and a high contrast of 6.8 when it was exposed to a 436‐nm line (g‐line), postbaked at 90 °C for 5 min, and developed with 1.69 wt % TMAHaq. A clear positive image of 8 μm line and space pattern was printed on film, which was exposed to 50 mJ/cm2 of g‐line by a contact printing mode and fully converted to the corresponding polyimide (PI) pattern on heating at 200 °C, confirmed by FTIR spectroscopy. Thus, this system will be a good candidate for next generation PSPIs. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3362–3369, 2009  相似文献   
58.
对于具有马氏调制费率的复合Poisson风险模型,用无穷小生成元构造鞅的方法,导出了破产概率的Lundberg不等式。  相似文献   
59.
A negative‐type photosensitive poly(phenylene ether) (PSPPE) based on poly(2,6‐dimethyl‐1,4‐phenylene ether) (PPE), a novel crosslinker 4,4′‐methylene‐bis [2,6‐bis(methoxymethyl)phenol] (MBMP) having good compatibility with PPE, and diphenylidonium 9,10‐dimethoxy anthracene‐2‐sulfonate (DIAS) as a photoacid generator (PAG) has been developed. This resist consisting of PPE (73 wt %), MBMP (20 wt %) and DIAS (7 wt %) showed a high sensitivity (D0.5) of 58 mJ/cm2 and a contrast (γ0.5) of 9.5 when it was exposed to i‐line (365 nm wavelength light), postexposure baked at 145 °C for 10 min, and developed with toluene at 25 °C. A fine negative image featuring 6 μm line‐and‐space pattern was obtained on the film exposed to 300 mJ/cm2 of i‐line by a contact‐printed mode. The resulting polymer film cured at 300 °C for 1 h under nitrogen had a low dielectric constant (ε = 2.46) comparable to that of PPE and a higher Tg than that of PPE. In addition, the cured PSPPE film was pretty low water absorption (<0.05%) as same as PPE. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4949–4958, 2008  相似文献   
60.
本文总设$F$是$p>2$的域,我们在域$F$上构造了有限维模李超代数$W(m,n,l,\underline{t})$, 定义了$W(m,n,l,\underline{t})$的$\Theta$-型导子,进而确定了它导子超代数.  相似文献   
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