基于Hopfield神经网络模型的通道布线算法

本文探讨了用Hopfield神经网络模型解决通道布线问题的一种新算法。算法描述了Hopfield模型与通道布线问题的映射方法和网络能量函数的构造方法,在能量函数中既考虑了合法解约束项,又考虑了优化解约束项,从而提高了布线质量。本文的意义还在于它证明了用Hopfield网络求解通道布线问题是可行的,有效的。     

小幅振动旋成体跨音速绕流的数值分析

假设绕小幅振动旋成体所导致的物理量的变化为平均定常扰动量的高阶小量,那么将物理量(速度、密度及压力)摄动展开后代入Euler方程,便导出了前两阶摄动量的控制方程和相应的边界条件,用TVD格式进行数值求解,得到了平均定常跨音速流(零阶)和基频(一阶)非定常分量的数值解。     

世纪末中国文学病态论

本文以宏观和俯瞰的视角,对90年代以来中国当代文学发展状况作了一次回观和审视．对文学发展中呈现出的诸钏病态提出了尖锐的、中肯的批评,如文学对“道”的放弃,文学家中缺乏“思想者”,文学创作对“底层”缺少应有的人文关注以及女性文学内质的退化弱化等等,并对其产生的恶果及原因作了一定程度的分析．指出文学家在面临危机与挑战时应有的姿态与选择,指出文学的生存发展除了受到社会外力的作用外,人的因素是第一位的。     

Genetic and physical finemapping of the Sc locus conferring indica-japonica hybrid sterility in rice （Oryza sativa L.）

Hybrid sterility is a major hindrance to utilizing the heterosis in indica-japonica hybrids. To isolate a gene Sc conferring the hybrid sterility, the locus was mapped using molecular markers and an F2 population derived from a cross between near isogenic lines. A primary linkage analysis showed that Sc was linked closely with 4 markers on chromosome 3, on which the genetic distance between a marker RG227 and Sc was 0.07 cM. Chromosome walking with a rice TAC genomic library was carried out using RG227 as a starting probe, and a contig of ca. 320 kb covering the Sc locus was constructed. Two TAC clones, M45EI4 and M90J01 that might cover the Sc locus, were partially sequenced. By searching the rice sequence databases with sequences of the TACs and RG227 a japonica rice BAC sequence, OSJNBb0078P24 was identified. By comparing the TAC and BAC sequences, six new PCR-based markers were developed. With these markers the Sc locus was further mapped to a region of 46 kb. The results suggest that the BAC OSJNBb0078P24 and TAC M45EI4 contain the Sc gene. Six ORFs were predicted in the focused 46-kb region.     

Adaptive terminal sliding mode control for high-order nonlinear dynamic systems

An adaptive terminal sliding mode control (SMC) technique is proposed to deal with the tracking problem for a class of high-order nonlinear dynamic systems. It is shown that a function augmented sliding hyperplane can be used to develop a new terminal sliding mode for high-order nonlinear systems. A terminal SMC controller based on Lyapunov theory is designed to force the state variables of the closed-loop system to reach and remain on the terminal sliding mode, so that the output tracking error then converges to zero in finite time which can be set arbitrarily. An adaptive mechanism is introduced to estimate the unknown parameters of the upper bounds of system uncertainties. The estimates are then used as controller parameters so that the effects of uncertain dynamics can be eliminated. It is also shown that the stability of the closed-loop system can be guaranteed with the proposed control strategy. The simulation of a numerical example is provided to show the effectiveness of the new method.     

论周代乐舞的审美价值——西周与东周乐舞的对比

周代是我国乐舞发展的一个辉煌时期,西周的雅乐,东周的俗乐。西周一整套严密的礼乐制度,到了东周“礼崩乐坏”已成大势。西周是中国舞蹈发展史上的第一个高峰。文章认为从美学的角度讲,东周才是中国历史上乐舞发展的第一个高峰,而西周只是一个过渡期。对于我国来说东周也才是真正意义上舞蹈艺术的开端。东周的乐舞艺术审美价值远远高于西周。     

辉映海峡两岸的散文双峰──余光中、余秋雨散文比较

余秋雨、余光中为两岸著名学者、散文家，他们的创作都超越了平庸，创造了神奇，成为２０世纪两岸散文的亮点。在某种意义上，他们的创作既代表了散文的成就，又代表了散文的高度。本文通过二者散文在文化态度等诸方面特点的比照分析，凸现二余散文的创作风格及其文史学地位，并力求从二者的创作心态、风貌中揭示两岸散文某些具有普遍性、代表性意义的特质与内涵。     

割线法计算二元相图

在分析相图计算原理及评述各种计算方法的基础上,提出了以扩展割线法(即单变量函数割线法的推广)计算Cu-Ni二元相图,在求解中采用前入数据,以扩展割线法进行迭代圆满地用计算机解出一组四元非线性方程组,与牛顿迭代法相比,此法无需求导、求逆及求雅可比矩阵等繁琐步骤,且对初值要求不苛,虽不像牛顿法以二阶收敛,但对方程数目不很多(其实三元系最多也只有8个方程)的相图计算,其收敛速度仍很可观,所需机时很短。