Abstract: Using the first-principle DFT method, the band structure and density of state are investigated. Then using the anharmonic oscillator model, the linear and nonlinear optical properties of frequency dependence are calculated for CBOB (Cd4BiO(BO3)3) crystal material. It is shown that the calculated SHG coefficient is well matched with our experimental value at a wavelength of 1064 nm, and a large nonlinear optical response originates from the charge transfers within the irregular BiO6, CdOn groups and BO3 group for Cd4BiO(BO3)3.
Abstract: Using the Least Mean Square (LMS) algorithm, this paper simulates two smart antenna models under the same signal environment. By analyzing and comparing 8-antenna elements linear array and 2*4- antenna elements rectangular array, this paper proposes the way to design the heterotypic antenna model. This antenna array can help system to gain similar performance of signal to interference plus noise radio(SINR) with reduced size of the antenna. The paper realizes the simulation of two models with the LMS algorithm. The antenna pattern and the curve about convergence of error have been given. It also analyzes the influence of the step length factor on LMS algorithm performance, and finds out the reasonable step to ensure fast algorithm convergence and to suppress interference effectively.
Abstract: With the development of numerically control and digital drive, it is a trend to put the Electronic Line-Shaft (ELS) technology into printing machine instead of the Mechanical Line-Shafting (MLS). After the shaftless reform of a printing machine for a factory, it was found that the printing accuracy and speed of most printing units was improved observably except the folding ripple. The paper analyzes the formation reason of folding ripple and the different characteristics between ELS and MLS. The research result shows that also there are many advantages in using ELS the synchronous capability is less than MLS when a periodic disturbance act on them under the same transmission stiffness. Therefore it is proposed that the AC motors must connect directly to the main printing roller to decrease the periodic disturbance and to increase the stiffness during the shaftless reform of printing machine.
Abstract: Color coordinates (0.1573, 0.0528) and (0.1542, 0.4663) have been identified in Ce3+ and Eu2+ singly doped calcium magnesium chlorosilicate (CMSC) phosphors, which present the purplish-blue and green lights under ultraviolet (UV) radiation, respectively. In Ce3+/Eu2+ co-doped CMSC phosphors, with sensitizing the green emission of Eu2+, Ce3+ co-doping changed the luminescence color from green to bluish-green, presenting a preferable mixed effect from two primary colors. Potential mixture of red phosphors will provide the possibility in achieving the ideal white fluorescence under UV-LED excitation.
Abstract: As a novel functional composite material, orthotropic piezoelectric composite material has been developed into various transducers used in the non-destructive technology and the structural health monitoring in aviation engineering, mechanical engineering, and civil engineering. In this study, the configuration and the mechanics-electric coupling property were described. A concept of the orthotropic ratio was proposed to derive the optimal length-to-width ratio of an actuator made of the orthotropic piezoelectric composite material. From the optimal length-to-width ratio, an optimal design method of the type 1-1 actuator, made of the orthotropic piezoelectric composite material, was advised. The mechanics-electric property of the type 1-1 actuator of orthotropic piezoelectric composite material designed by this approach was simulated with the software COMSOL under different actuating voltages. The modeling results were validated by experiments. It was evident that the results of numerical simulation were good agreement with that of experiments.
Abstract: Standing surface acoustic wave (SSAW) technology combined with microtechnology opens up new areas for the development of advanced microparticle and cell separating microfluidic system. A novel SSAW sensor made of the orthotropic piezoelectric composite material (OPCM) is proposed and described. A SSAW field with target wavelength can be generated by this technology and with this new sensor. The wavelength of SSAW generated by this sensor can vary the range from several to a few hundred micrometers. The acoustic radiation force (ARF) generated by the SSAW field can be used to manipulate different dimensional particles.
Abstract: In order to meet real-time and quick requirements for video information acquiring and processing, this paper introduces a hardware platform based on Altera's Cyclone series EP1C12Q240C8, to descript the driving timing for CMOS image sensor OV7620 with Verilog HDL language to acquire video information. The system uses SCCB programming model, establishes communication between FPGA chip and CMOS image sensor to achieve the control and acquisition of the signal. In order to achieve operational requirements in different environments and needs, the corresponding registers and the controller are set within CMOS image sensor. Experimental results show that the control of the CMOS image sensor OV7620 flexibly provides a stable and reliable source of raw information for video monitor, industrial applications such as on-site monitoring.