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Holographic polymer dispersed liquid crystals (H-PDLCs), which is one of promising material for LC display, when doped with nanoscale silver (nano Ag) exhibit a unique electro-optical response to frequency modulation. We established an equivalent circuit model for H-PDLC doped nano Ag gratings according to Maxwell-Wagner effect and calculated relaxation frequency for three concentrations of nano Ag. We found that the frequency modulation and doping concentration have a close effect on threshold driving voltage of H-PDLC gratings. It is experimentally shown that the lowest threshold driving voltage can be obtained when the driving frequency is located just around the recipe's dielectric relaxation frequency. It is possible to decrease the driving voltage of H-PDLC through selection of suitable driving frequency as well as via doping with appropriate concentration of nano Ag.

A four-channel frequency division multiplexed fluorescent microscope (FDMFM) modulated by holographic polymer dispersed liquid crystal (H-PDLC) grating array is presented in this paper. The four-channel H-PDLC grating array is developed and employed to generate frequency modulation. Fluorescent signals at four different locations on a rat neural cell have been successfully modulated with four different frequencies, collected by a single high-sensitivity photodetector, such as photomultiplier tubes, and distinguished by taking the Fourier transform of the detected sum signal. The experimental and simulation results agree well. The new system offers the advantages of (1) multiple channel modulation capability, (2) no mechanical noise and (3) flexible and controllable modulation profile (e.g. square wave, triangular wave, etc.). Thus this four-channel FDMFM system can be very helpful for studying fast-changing transient events in biological samples.

We experimentally demonstrated an electrically controlled variable focus optical system based on cascading polymer dispersed liquid crystal (PDLC) lens. Through adjusting external electric field applied on the hole-type electrode of PDLC lens to change the spatial distribution of refractive index of PDLC, the plane PDLC cell can be functioned as a focusing lens with the variable focus length. In this article, we simulate the electromagnetic field distribution of the external electrical field, as well as analysis the corresponding principle and mathematic equation of its electrically controlled focusing length. The experimental results show that as external alternate current (AC) voltage is increased from 0 to 80 V, the focal length of single lens decreases from ∞ to 1.073 m, and that of the double lens from ∞ to 0.484 m. These experimental results are in good accordance with the simulation results. The experimental response time of PDLC tunable lens is less than 1 ms, which will bring benefits for the applications especially for the fast imaging system. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2830–2835, 2013

The competitiveness in today's market forces many companies to rethink how to organize the enterprise resource. Many manufacturing companies are developing families of products to provide enough variety for the marketplace while keeping costs relatively low. As the traditional similarity measure used in module division is to the design stage in which the features and set are static, it is impossible to find the similar components in alterative design stages. For this reason, a new module division method on extension-distance is presented. In the different design environments, three distance concepts are discussed, namely, feature-to-feature, feature-toset and set-to-set. The first concept will be employed as the base for extension-cluster method in the platform design on the thought of each structure' s features between two adjacent structure components, while the second is used to build the function constraint in the customized components division for the virtual organization process. In the extension-cluster method, product adaptability measure is induced to evaluate whether the platform is adaptable compared to fuzzy cluster measure.

Cultivating the teacher's information ethics has double meanings, concerning teacher's own information literacy, will influence the instruction activity and students' information ethics too, it is the important component of teacher's information literacy. But teacher's information ethics education is often ignored. How to know and how to cultivate the teacher's information ethics correctly is an important and thorny problem. This article mainly explains the importance of cultivating teacher's information ethics, analyzes current situation of teacher's information ethics in our country, finally, makes a suggestion on how to promote the teacher's information ethics.

Millimeter wave (MMW) radar is booming in application to target seeker onboard the air-to-air missile (AAM), which has the capability to obtain all-weather radar images for auto target recognition (ATR) and intelligent active homing guidance. An advanced simulation system for MMW imaging radar seekers of AAM was introduced in this paper. The system is composed of parameter initialization module, signal simulation module and image formation module. It is capable of investigating and demonstrating the system performance of MMW radar seeker. The modeling of radar signal and the geometric model for missile-to-target were presented in particular. The echo signal for major radar operation modes could be generated by the system, including high-resolution range profile (HRRP) mode, Doppler beam sharpening (DBS) mode as well as the high-resolution burst-SAR mode. The image formation algorithms for each radar operation mode were integrated in the system to generate highly accurate radar imagery. Computer simulation results for an actual aircraft were presented, which validate the correctness of the simulation system. It is an advanced tool for the investigation of imaging algorithms and the optimization of the system parameter selection, as well as the demonstration of the radar scenario