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51.
本文提出新型布线算法,集李氏迷宫法与线搜索法的长处为一体,以饱和带法进行动态排序,以线搜索法确定借孔位置,然后用李氏法进行单层布线,获得最佳路径,从而达到线型好,布通率高的效果。  相似文献   
52.
存在未建模动态时,如何去除系统传递函数估计中噪声引起的偏差是系统辨识关心的重要问题。本文将我们已提出的BELS方法进行推广得出:当系统未建模动态可用-FIR模型描述时,应用本文的方法可得到系统传递函数的无偏辨识,而不需知道有关噪声和未建模动态概率分布函数的先验知识。  相似文献   
53.
论述了合成聚氧乙烯油酸酯的较佳反应条件,探讨了不同EO加成数的聚氧乙烯油酸脂的表面物性规律。  相似文献   
54.
Catastrophic convolutional codes (CC) cause an infinite number of decoded data bit errors when decoding a finite number of code symbols. A CC displays a catastrophic error propagation if the generating polynomials have a common factor. An efficient algorithm for polynomial factorization in GF(2m) is used for detecting catastrophic CC for any rate n/m and constraint length k. A general formula is derived to calculate the number of catastrophic codes in any (m, n, k) CC.  相似文献   
55.
This paper explains the principle of a method which avoids printing of phantom resist lines due to undesired intensity minima appearing on Cr-less edge line phase-shifting masks. The method combines principles of grey-tone lithography and attenuated phase-shifting masks to give, what we call, a Cr-Less Attenuated Phase-shifting mask (CLAP). Rules for generating a CLAP design and a paradigm setup of a CLAP mask are presented. The capabilities and possible limitations of the CLAP method based on simulated results for a standard wafer stepper setup using the SOLID lithography simulator are being assessed.  相似文献   
56.
A CEC-funded project has been performed to tackle the problem of producing an advanced Life Monitoring System (LMS) which would calculate the creep and fatigue damage experienced by high temperature pipework components. Four areas were identified where existing Life Monitoring System technology could be improved:
1. 1. the inclusion of creep relaxation
2. 2. the inclusion of external loads on components
3. 3. a more accurate method of calculating thermal stresses due to temperature transients
4. 4. the inclusion of high cycle fatigue terms.

The creep relaxation problem was solved using stress reduction factors in an analytical in-elastic stress calculation. The stress reduction factors were produced for a number of common geometries and materials by means of non-linear finite element analysis. External loads were catered for by producing influence coefficients from in-elastic analysis of the particular piping system and using them to calculate bending moments at critical positions on the pipework from load and displacement measurements made at the convenient points at the pipework. The thermal stress problem was solved by producing a completely new solution based on Green's Function and Fast Fourier transforms. This allowed the thermal stress in a complex component to be calculated from simple non-intrusive thermocouple measurements made on the outside of the component. The high-cycle fatigue problem was dealt with precalculating the fatigue damage associated with standard transients and adding this damage to cumulative total when a transient occurred.

The site testing provided good practical experience and showed up problems which would not otherwise have been detected.  相似文献   

57.
Among the photocathodes used for particle identification based on the Cherenkov Ring Imaging technique, the TMAE molecule is still the best in terms of quantum efficiency. Despite the fact that TMAE gaseous photocathodes have already been used in a number of large experiments, one still seeks answers to many detailed questions. We present a systematic study of gaseous photocathodes based on TMAE mixed with helium, hydrocarbon and CF4-based gases at normal pressure. The study includes a measurement of the electron drift velocity, gas quenching properties, single electron pulse height spectra and anode wire aging. The paper makes recommendations for carrier gas mixtures to obtain the best quenching, and suggests how to manage TMAE wire aging. This study was motivated by a specific particle identification detector proposal, the Fast Drift CRID proposed for the B-factory at SLAC.  相似文献   
58.
A large quantity of laminated fine grain zones were observed in the Al-Mg-Li alloy weld metal by manual TIG, which was not found in ordinary Al alloy welds. The fine grain zone is formed because of the Al3(Zr,Ti) particles in the filler metal and the manual filling of filler metal in welding process  相似文献   
59.
CA/PAN中空纤维血浆分离膜的结构与性能   总被引:4,自引:2,他引:2  
本研究以CA及PAN的共混溶液,通过干-湿法纺丝制取中空纤维,利用共混高聚物各组分在凝固剂中相分离速度的差异,形成具有稳定结构的中空纤维孔膜,该膜用于分离血液中的血浆成分具有良好效果。讨论了成型条件及添加剂等对膜结构、性能的影响,用SEM及图相分析仪、MAP压汞仪及DSC等分析手段,对膜的微孔结构、形态、孔尺寸及中空纤维膜的血浆通量和水通量等进行了系统的考查。  相似文献   
60.
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