关于设计的十年一问(下)

以十年分段,针对1900年到2000年110年间的11件经典设计作品,展开了对设计的一系列追问,包括宏观层面的工业化问题、商业化问题、创新问题；史观层面的包豪斯理想、人道主义精神与后现代趣味；微观层面的形式美问题、材料问题、技术问题、人机问题与情感问题等,以此帮助我们认识并理解设计的本质特性,使我们的知识能力、工作方法和思维方式不断充实与完善,以适应并解决社会诸环节发展变化所带来的新问题与新视点.     

关于结缕草草坪秋季覆膜的对比研究

本文通过对覆膜与未覆膜的晚播结缕草草坏主要生长指标的对比测定，得出结论：对晚播的结缕草草坪进行秋季覆膜，可延长其生长期有绿期，提高幼苗成活率，并保证结缕草幼苗安全越冬。     

桥式起重机主梁下挠处理新技术

采用高强度钢丝绳作为张拉元件，对２０ｔ抓斗吊车主梁进行预应力法下挠处理，恢复了主梁上拱度，取得预期效果。对所使用张拉钢丝绳的拉力、挠曲线方程和下料理论长度作了理论计算分析，并且应用计算机仿真技术取代吊车动态负荷电测试验，获得主梁动刚度、桥架主梁和钢丝绳组动载系数等动态特性参数。     

胡萝卜汁中胡萝卜素的快速测定

胡萝卜汁中由于含有较多的果胶，在进行胡萝卜素测定时，很难将胡萝卜素提取完全，造成较大的测定误差。本法采用了提取胡萝卜素时先加入无水Ｎａ２ＳＯ４洗涤净化，然后直接比色测定胡萝卜汁中的胡萝卜素，并进行了精密度，回收率试验和ＧＢ１２３８９－９０纸层析法进行了显性差异检验，得到了较满意结果。此方法可专用于胡萝卜汁中的胡萝卜素含量的快速测定。     

小波神经网络用于原子半径的研究

采用原子的第一电离能与原子的核外电子分布作为输入参数，使用已知的半径值作为训练样本，对小波神经网络进行了训练并成功地预报了８６种元素的原子半径，较完整地补充了共价半径、金属半径与范德华半径标度方法中所缺的相应值．结果表明，对于原子及分子物理的研究，小波神经网络是一种很有潜力的工具．     

基于C/S构架的读者身份认证系统

现有读者身份系统单机运行,存在维护管理不便。为了解决这一问题,本文提出了基于C/S构架的读者身份认证系统,该系统网络化运行,便于维护与管理,同时为图书馆资料的高效利用提供决策依据。文中具体叙述了系统的设计与实现。     

Generating oxygen adatoms on Au(997) by thermal decomposition of NO<Subscript>2</Subscript>

We report our investigation of the interaction of NO₂ with the Au(997) vicinal surface by high-resolution photoelectron spectroscopy using synchrotron radiation as the excitation source. At 170 K, both core-level and valence-band photoemission results illustrate the decomposition of NO₂ on the Au(997) surface at low NO₂ exposures, forming coadsorbed NO(a) and O(a) species. After annealing at 300 K, NO(a) desorbs from Au(997) whereas O(a) remains on the surface. Upon annealing at 750 K, we observe no signal for adsorbed oxygen on Au(997). These results clearly demonstrate that thermal decomposition of NO₂ is an effective method to generate oxygen adatoms on Au(997) under ultrahigh-vacuum conditions.     

Harmonic retrieval in colored ARMA noise

We propose a new approach to harmonic retrieval in colored ARMA noise. A suitable filter is first used to remove all the sharp power spectrum peaks of the noisy observed process, then some kinds of cross correlation is employed to identify the noise characteristics. After filtering the noisy observed process with the identified noise characteristics again, SVD-TLS method can be applied to retrieve the harmonics. The proposed approach can be used to retrieve real-valued harmonic signals in colored ARMA noise with no restrictions on the phase coupling of harmonics and the distribution of the noise. Simulation examples show its effectiveness. Foundation item: Supported by Shanghai Post & Telecom Administration-SJTU Inf. and Telecom Joint Lab Project (1999-GR1-3) Biography: Li Sheng-hong (1971-), male, Postdoctor, research direction: statistical signal processing and intelligent technology application in broadband networks.     

层流边界层方程的Stewartson解法

介绍了采用斯蒂文森算法解完全流体的二维、定常、可压缩层流边界层方程的方法.先用斯蒂文森变换化简层流边界展方程,再用曲线拟合的方法具体求解出各参数.     

Fault detection and diagnosis for data incomplete industrial systems with new Bayesian network approach

For the fault detection and diagnosis problem in largescale industrial systems,there are two important issues: the missing data samples and the non-Gaussian property of the data.However,most of the existing data-driven methods cannot be able to handle both of them.Thus,a new Bayesian network classifier based fault detection and diagnosis method is proposed.At first,a non-imputation method is presented to handle the data incomplete samples,with the property of the proposed Bayesian network classifier,and the missing values can be marginalized in an elegant manner.Furthermore,the Gaussian mixture model is used to approximate the non-Gaussian data with a linear combination of finite Gaussian mixtures,so that the Bayesian network can process the non-Gaussian data in an effective way.Therefore,the entire fault detection and diagnosis method can deal with the high-dimensional incomplete process samples in an efficient and robust way.The diagnosis results are expressed in the manner of probability with the reliability scores.The proposed approach is evaluated with a benchmark problem called the Tennessee Eastman process.The simulation results show the effectiveness and robustness of the proposed method in fault detection and diagnosis for large-scale systems with missing measurements.