从设计上提高FPC使用性能

文章主要介绍了FPC在三维组装过程中经常出现的几类问题以及解决方法。供FPC设计人员参考,以从设计上提高产品的使用性能及品质。     

多品种柔性生产企业的订单调度模型及其遗传算法

以订单总完工时间最小和订单平均流程时间最小为目标函数,利用改进的多目标遗传算法生成了多品种订单调度模型.为解决组合模型的指数爆炸问题,提出了一种按规则分配订单以及订单中各作业排序相结合的集成调度思想;以一种整数和字母组合的编码方法用于可行解的表达,并在每个分目标的进化过程中,对选择、交叉、变异算子以及精英解保留策略重新进行设计,保证了解的分布性和均匀性;同时还提出了一种新的终止条件,将精英种群与分目标的子种群进行合并,从而加快收敛的速度.以典型的订单生产企业为例进行仿真实验,实验结果表明,应用该算法可以获得满意的Pareto解集.     

Recent advances in flexible and stretchable electronics, sensors and power sources

There has been ongoing keen interest to mold electronic devices into desired shapes and be laid on desired configurable surfaces. In specific, the ability to design materials that can bend, twist, compress and stretch repeatedly, while still able to maintain its full capability as conductors or electrodes, has led to numerous efforts to develop flexible and stretchable (bio)devices that are both technologically challenging and environmentally friendly (e.g. biodegradable). In this review, we highlight several recent significant results that have made impacts toward the field of flexible and stretchable electronics, sensors and power sources.     

基于柔性基底异质结有机薄膜的光伏器件

研究了基于柔性基板的有机薄膜太阳能电池,实验以聚3,4-乙撑二氧噻吩/聚苯乙烯磺酸盐作为阳极修饰层,1,4-亚苯基亚乙烯基（MEH-PPV）材料作为给体层以及富勒烯（C60）材料作为受体层制备异质结柔性有机太阳能电池。实验结果表明:增加阳极修饰层,虽然会阻挡光的吸收,但是可以大幅度地提高短路电流、开路电压、填充因子和能量转换效率4个参数。并发现MEH-PPV受体层的厚度对有机太阳能电池的性能有较大影响,当受体层厚度为90 nm时能量转换效率达到最大,为1.29%。     

In situ X-ray structural studies of a flexible host responding to incremental gas loading

Crystallographic pressure-lapse snapshots of a porous material responding to gas loading were used to investigate the stepwise uptake of carbon dioxide and acetylene molecules into discrete confined spaces. Based on the data, a qualitative statistical mechanical model was devised that reproduces even subtle features in the experimental gas sorption isotherms.     

Polyspherical Coordinate Systems on Orbit Spaces with Applications to Biomolecular Shape

A general theory of molecular internal coordinates of valence type is presented based on the concept of a Z-system. The Z-system can be considered as a discrete mathematical generalization of the Z-matrix (a molecular geometry file format familiar to chemists) which avoids the principal disadvantage of Z-matrices. Z-matrices are usually only employed for small molecules because there is no easy way to glue two Z-matrices together to get the Z-matrix of a larger molecule. It is shown that Z-matrices are simply Z-systems together with additional extraneous structures and that the Z-systems for any two molecules can be naturally glued together to obtain a Z-system for the combined molecule. A general mathematical framework suitable for the detailed study of molecular geometry is introduced and applied to five and six-membered molecular rings. A classification of shapes of hexagons with opposite sides and angles congruent is given with explicit parameterizations of the flexible and rigid solutions. The entire mathematical formalism generalizes to a theory of polyspherical coordinate systems on orbit spaces of the group of -dimensional rigid motions acting on finite collections of points in -dimensional Euclidean space. The -dimensional Z-system is a new discrete structure related to abstract simplicial complexes, graded posets, and iterated line graphs. Complete proofs of all the -dimensional results are given, and connections to other areas of mathematics are noted.     

Flexible resistance memory devices based on Cu/ZnO:Mg/ITO structure

Resistance memory devices based on a Cu/Mg‐doped ZnO/indium‐tin‐oxide structure on a PET (polyethylene terephthalate) flexible substrate were fabricated. The devices showed stable bipolar resistance switching property and good flexibility. The high to low resistance ratio was larger than 30 times, the endurance was more than 10² cycles, and the resistance retention was longer than 10⁴ s. The resistance values of both high and low resistance states were not significantly changed by bending in a radius (≥20 mm) for more than 10³ times. This resistance switching phenomenon of our devices can be explained by creation/rupture of metal conductive channels induced by electrochemical migration of Cu ions. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

基于遗传算法的多目标柔性工作车间调度问题求解

本文针对柔性工作车间调度问题给出了一个有意义的综合目标尽可能缩短制造周期的同时尽可能的减少机器负荷。由于传统遗传算法在多目标柔性工作车间调度问题上的局限性，我们提出了一种改进遗传算法：首先，我们给出了针对综合目标的工序调度算法获得初始集合；接着，针对柔性工作车间调度问题的特点，我们在常用的基于工序顺序的编码方法上融入了基于机器分配的编码方法，并据此设计了相应的交叉变异操作；最后借鉴了物种进化现象中的环境迁移思想设计了解决多目标优化问题的迁移操作。实验结果表明，改进的遗传算法在多目标柔性工作车间调度问题的解决上要优于传统遗传算法。     

A Novel Nanocrystalline TiO2 Thin Film Electrodes Prepared at Low Temperature

Nanocrystalline TiO2 thin films were successfully prepared by a new ““water-cooked““ method on both conductive glass substrates and flexible substrates at low temperature. Dye-sensitized solar cells based on these films have exhibited high overall light-to-electricity conversion efficiencies of 4.67 % and 1.94 % on conductive glass substrate and flexible substrate, respectively, under the illumination at 100 mW/cm^2.     

挠性PCB用基板材料的新发展（1）——FCCL发展的综述与特点

该文主要阐述2003年￣2004年间挠性覆铜板在生产厂家及在所用材料(包括PI薄膜、铜箔)、新技术、新产品方面的新发展。