VB编程中的几个小技巧

利用VB中的InStr函数、Like运算来实现数据的模糊查找,以及利用随机码进行加密.     

压电超精密定位台的动态迟滞建模研究

为了提高压电超精密定位台的建模精度,采用Backlash-Like迟滞非线性模型来描述压电超精密定位台的迟滞特性,采用基于遗传因子的递推最小二乘法来辨识Backlash-Like模型的参数,并结合压电超精密定位台的动态特性,建立了压电超精密定位台的二阶动态迟滞模型。通过实验得到,对比Backlash-Like模型,动态迟滞模型在频率为30和40 Hz时,最大输出位移误差由1.21和1.39μm下降到0.32和0.44μm,且最大相对误差分别仅为3.5%和4.4%,平均位移误差由0.53和0.76μm下降到0.17和0.21μm,平均相对误差由1.93%和3.38%下降到1.11%和1.37%。实验结果验证了提出的动态迟滞模型,既能减小了因压电超精密定位台的动态特性而引起的系统误差,又能很好地模拟其迟滞特性与动态特性,并且避免了不同频率下的模型参数反复辨识问题,提高了压电超精密定位台在高频、快速、大行程定位中的精度。该方法简单且适应性强,易于工程实现。     

Carlos Zapata and Antonio Citterio's Cooper Square Hotel,New York

Unlike most glamorous new high-rise apartment buildings in downtown Manhattan, this thin, tilted white glass tower provides homes away from home for chic out-of-towners. And what ‘homes’ they are. Upstairs are astounding long-range views; on the lower floors, a series of glass-walled lounges, restaurants, balconies, a garden and even a library with a wood-burning fireplace. And, as Jayne Merkel explains, these sensual pleasures are mixed with intellectual ones. There are art and travel books in every room and guests can enjoy ‘movie nights’ in the screening room.     

镍基单晶合金热处理的组织演化与有限元分析

通过对一种含Re单晶镍基高温合金热处理期间及不同时效温度组织形貌的观察,结合有限元分析,研究合金中γ′相在热处理期间及蠕变期间的组织演化规律。结果表明,在固溶热处理期间,γ′相以蝶形组合从基体中析出;一次时效期间,γ′相长大为立方体形貌;二次时效期间,γ′相略有长大,排列更加规则。经不同温度的一次时效后γ′相尺寸逐渐长大,立方度增加。最后确定出该合金合理的热处理工艺。     

Investigation of Tribo-Chemistry by Means of Stable Isotopic Tracers,Part 2: Lubrication Mechanism of Friction Modifiers on Diamond-Like Carbon

A solution of glycerol monooleate (GMO) in polyalphaolefin (PAO) considerably reduced the friction between the steel and the diamond-like carbon (DLC) under boundary conditions. The combination of the material-oil-additive is of importance. Model additives composed of a stable isotope ( ² H or ¹³ C) were employed to trace the additive molecule by time-of-flight secondary ion mass spectroscopy (TOF-SIMS). It was found that the additive interacted with DLC surfaces in the form of an ester. Inclusion of PAO in the boundary film on DLC was found by TOF-SIMS analysis.The utility of the isotopic tracer technique in tribo-chemistry was demonstrated in this study.     

Moral obligation in online social interaction: Clicking the “like” button

Social media greatly facilitate online social interaction among friends, and user behavior in social interaction may be influenced by interpersonal relationships. While individuals sometimes do enjoy the content shared by friends, they may also feel that they have a moral obligation to like what their friends share. Drawing on the stimulus-organism-response model, this paper examines whether the characteristics of interpersonal relationships are associated with moral obligation as well as whether moral obligation is associated with “like” intention. By using data from 348 users of WeChat Moments, we provide empirical evidence that the stimuli of interpersonal relationships (perceived authority, perceived closeness, and peer referent) are positively associated with the sense of moral obligation, which in turn, is positively associated with user intention to click the Like button on their friends’ postings on social media. Theoretical and practical implications of the findings are discussed.     

Lucene在数据库全文检索中的性能研究

通过Lucene API实现对MYSQL数据库的全文检索,并将Lucene全文检索的性能和查全率同数据库全文检索和Like子句检索作对比.通过对比发现Lucene全文检索在性能上接近数据库全文检索,检索耗时约为Like子句检索的1/5.在对中文检索方面能达到77.2%的查全率,大大高于数据库全文检索.因此对于数据量较大的MYSQL数据库,Lucene全文检索将是一个很好的选择.     

From the Subversive to the Serious: Temporary Urbanism as a Positive Force

Pavilions and pop-ups are most often perceived as standalone objects, but what do transient structures have to offer at the city scale? Peter Bishop , Professor of Urban Design at the Bartlett School of Architecture, University College London (UCL), and a director at Allies and Morrison, explores what temporary urbanism can contribute to the wider metropolis. He describes how when they grow out of the best of intentions and are well executed, pavilions and pop-ups can potentially inject joy and delight, enriching an over-planned and over-regulated city.     

Influence of silk,like finishing on polyester fabric drapability北大核心CSCD

Silk, like finishing of pure polyester fabric has been a common industrial treatment method. This method can make polyester fabric closer to the texture of natural silk in terms of drapability and hand feeling. To study the improvement effect of silk, like finishing on fabric drapability, five types of polyester fabrics were treated in different conditions. YG811 fabric drapability tester was used to test the drape coefficient, and the main mechanical performance index was tested by the FAST fabric style tester. It is verified that the silk, like finishing conditions of and structural parameters of fabric have a significant influence on the drapability of treated fabric. For the same fabric with different silk, like finishing, its drape coefficient shows a negative correlation with weight loss ratio and has a linear relation with shear stiffness and bending rigidity. © 2018 China Silk Association. All rights reserved.     

基于网络邻域拓扑的粒子群优化算法

探讨类无标度网、全局耦合网、环形网、随机网、星形网等邻域拓扑结构对粒子群优化算法寻优效果的影响。理论分析与实验结果显示,以类无标度网作为邻域拓扑结构的粒子群优化算法在误差范围内的寻优效果最好,收敛速度最快,可以较好地避免陷入局部最优,且网络平均度对粒子群优化算法的寻优效果有一定的影响。