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This work set up a Lamb wave excitation device for assembling polystyrene nanospheres into 3D photonic crystals (PCs) of face-centered cubic structures. The optical property of fabricated PCs was verified by transmittance spectra measurements.

This work investigated the phenomena and cause of photonic band gap (PBG) shift under an open environment at −10 °C ∼ 20 °C for the three-dimensional (3D) photonic crystals (PCs). The 3D PCs were composed of polystyrene spheres using the self-assembly method. The reflective gloss of 3D PC sample underwent non-monotonous color change within the temperature region. PBG of PCs first red-shifted during the cooling from room temperature. Later, the PBG blue-shifted when the temperature decreased from about 0 °C. The average transmittance through the PC sample within the visible range also increased first and then decreased with ambient temperature reduction. Influences from structure dimension, optical constants of involved materials, condensation and its phase change on PBG were all quantitatively investigated.

This work both numerically and experimentally investigates hemispherical radiative properties (absorptance, reflectance, and transmittance) of complex gratings. Crystal silicon is employed to generate samples. One is a double-sided polished 520-μm-thick substrate, and the other is a substrate with complex gratings on its top. The incidence wavelength λ ranges from 0.5 μm to 1.7 μm, containing the intrinsic band gap wavelength λbg = 1.09 μm. Wavelength-selective and polarization-sensitive features are exhibited in spectra of properties for complex gratings. The wavelength-selectivity and polarization-sensitivity are elaborated using near-field electromagnetic patterns at three representative wavelengths (λ λbg).

This work developed a type of energy-saving glass for regions undergoing sun glare and high temperature. Its functions cost zero energy and negligible weight increment (1.81 g/m2). The key to its success was two-dimensionally periodic nanostructures composed of single material. These nanostructures were arranged in a hexagonal way and added on a commonly-seen glass substrate. The area of these structures was scalable, and their fabrication was cost-effective using nanoimprint lithography technology. The glass was able to exhibit broadband wavelength-selective transmittance. Measured spectra confirmed transparency in the visible and approximate opaqueness in the near-infrared regions. The power for indoor illumination and air conditioner could thus be simultaneously saved. This work also utilized numerical modeling to obtain electromagnetic field patterns in the near-field. The patterns explained the broadband wavelength-selectivity and influences from an adhesive layer existing in real samples.

InGaN/GaN-based green light-emitting diodes (LEDs) with high-density ultra-small In-rich quantum dots (QDs) embedded in InGaN multiple quantum wells via spinodal decomposition are grown by metal organic chemical vapor deposition. The density and average size of In-rich QDs increased from 1 × 1011 cm−2 to 2 × 1012 cm−2 and decreased from 8.4 nm to 2.3 nm, respectively, when the NH3 flow rate was reduced during the growth of InGaN active layers. The associated growth mechanism of QDs is discussed. High-density ultra-small QDs with improved internal quantum efficiency due to good carrier confinement and a small number of defects are obtained. The proposed approach improves the light emission efficiency of InGaN QD-based LEDs and a 10% enhancement in light output power for packaged lamp-form LEDs is demonstrated in this work.

Skin color is the significant information for many emerging applications in surveillance systems. However, the common skin color models usually need to perform color space transformation. This is not suitable for direct hardware implementation. This paper develops a statistical skin color model using the default RGB color space, which is especially suitable to implement on hardware for image processing applications. Moreover, an efficient face detection system is also proposed with our skin color model for hardware implementation. Compared with other skin color models, the proposed model produces the highest detection rate. Furthermore, the extended face detection system also significantly decreases the computational cost of the hardware implementation based on our skin color model. Experimental results demonstrate that our proposed detection system can be easily implemented on a field-programmable gate array (FPGA), where only 3202 logic cells is occupied with the high detection rate.

Over the last few years, human computer interaction has become an active research area, which releases people from inactive, inconvenient communication with machine. In this paper, an automotive infotainment system with intelligent applications is presented. The proposed system combines the interactive gesture control for controlling in-car applications which can enhance safety and driving performace, as well as increase the level of comfort in modern vehicles.

Image binarization involves converting gray-level images into binary ones, which has significantly impacted on intelligent portable devices in recent years. Given the limited memory space and computational power of portable devices, reducing the computational complexity of algorithms which work on embedded systems is of priority concern. This paper proposes a 2-D intelligent block detection algorithm with more accurate region segmentation for document image binarization. by combining merits of global and local algorithms, the proposed approach provides an effective outcome and a low computational cost. as demonstrated by the experimental results, the proposed algorithm is slower than Otsui¦s method but 275 times faster than local methods.

This paper presents the architecture and implementation of a real-time adaptive Wiener filter for non-stationary noise cancellation in a car environment. The Wiener filter has been implemented in a Xilinx Virtex-5 chip and the target device is chosen as xc5vlx110t. The proposed design can filter each 32 samples within 918 micro seconds. The peak sampling rate is estimated to be 88.6KHz. The performance of proposed design is measured as 15.85dB noise reduction.

License plate recognition system (LPR) plays an important role in many applications such as access control, traffic control, and the detection of stolen vehicles. A LPR system can be classified into the detection and recognition parts. Improvement of the detection part will be discussed in this paper. Binarization of plate images is one of the major tasks of detection which consumes huge processing time and impacts on the recognition rate. This paper proposes an efficient binarization algorithm with intelligent block size detection. Based on image characteristics, the plate image is automatically divided into several blocks with various sizes. Then, a threshold surface is constructed to derive the binary image. Experimental results show that the proposed method not only provides promising binarization result, but also low computation cost.

Skin color is an important feature for face detection and recognition in color images. In order to obtain the possible face regions in color images, the skin color models are always constructed by statistical analysis. Owing to low accuracy of the static models, researches have discussed several dynamic models to correct input image such as illumination compensation, white balance, edge points addition, etc. Unfortunately, it is possible that some objects whose color is the same as the definition exist, and the previous methods can not separate real skin item from skin color background. Thus, to enhance skin color separation, this paper presents a honeycomb model to recognize the real human skin and the skin color items. First, the possible skin color is estimated from the pixels of database, and the honeycomb structure is built in HSV color space according to the training samples. Then, the personal skin is captured in one of the honeycomb cells. The performance of the new skin color detector technique has been tested under complex lighting source and background environments. It is observed that the proposed model can effectively improve the segmentation results. Especially, the honeycomb model is capable of separating the human face which connected with other face or skin color background.

Recently, VNC (virtual network computing) has become one of the popular remote access techniques for Internet applications such as remote distant learning and collaborative application systems. However, there is no any multimedia functions have been implemented to enhance the performance. In this paper, we presents a framework based on remote frame buffer (RFB) and real-time protocol (RTP) to provide real-time video and audio transmissions for multimedia applications. The framework can be applied to build distance collaborative environments with multimedia and RTP (real-time transport) features efficiently.

In this paper, the floorplan-aware topology of hierarchical power quad-grids is proposed to dynamically meet the local requirement of high current densities inside the floorplan and an iterative linear voltage/current scaling (ILVCS) approach is proposed to meet the current electromigration and voltage IR-drop constraints phase by phase. The experimental results show that our proposed ILVCS approach based on hierarchical power quad-grids can obtain 23%/spl sim/44% improvement on total wiring area than the power grids by the wire sizing method for the tested examples.

The dynamic structure of a hierarchical stair contour is firstly proposed to maintain an incremental floorplan contour for the placement of a sequence of given blocks. Based on the LB-packing process of any given block in a compact floorplan, a double-bound list (DBL) is further proposed to represent the geometrical adjacent relations in a compact floorplan. Finally, an SA-based approach based on the combination of one rectangular-packing process and one LB-packing process as one perturbation operation is proposed to allocate and integrate the possible decaps of all the blocks into the original floorplan. Experimental results show that our proposed SA-based allocation approach based on DBL representation obtains very promising results for MCNC benchmark circuits.

A probabilistic congestion prediction approach in a dynamic hierarchical quad-grid model is proposed to be applied in timing-constrained congestion-driven global routing (TCGR). Experimental results show that the TCGR algorithm (Yan, J.T. and Lin, S.H., Asia-Pacific Design Automation Conf., p.683-6, 2004) with the proposed probabilistic congestion prediction can use less CPU time to obtain a better timing-constrained congestion-driven global routing result for the tested benchmark circuits.

Skin colour is an important feature for face detection and recognition in colour images. To obtain the possible face regions in colour images, skin colour models are always constructed by statistical analysis. Owing to low accuracy of the static models, researchers have discussed several dynamic models to correct input images. Unfortunately, it is possible that some objects whose colour is the same as the definition exist, and the previous methods cannot separate real skin item from skin colour background. Thus, this paper presents a honeycomb model to recognise the real human skin colour. The performance of the new skin colour detector technique has been tested under complex lighting source and background environments. It is observed that the proposed model can effectively improve the segmentation results. Especially, the honeycomb model is capable of separating the human face which connected with other face or skin colour background.