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251.
The core of smoothed particle hydrodynamics (SPH) is the nearest neighbor search subroutine. In this paper, a nearest neighbor search algorithm which is based on multiple background grids and support variable smooth length is introduced. Through tested on lid driven cavity flow, it is clear that this method can provide high accuracy. Analysis and experiments have been made on its parallelism, and the results show that this method has better parallelism and with adding processors its accuracy become higher, thus it achieves that efficiency grows in pace with accuracy.  相似文献   
252.
Hilbert-Huang transform method has been widely utilized from its inception because of the superiority in varieties of areas. The Hilbert spectrum thus obtained is able to reflect the distribution of the signal energy in a number of scales accurately. In this paper, a novel feature called ECC is proposed via feature extraction of the Hilbert energy spectrum which describes the distribution of the instantaneous energy. The experimental results conspicuously demonstrate that ECC outperforms the traditional short-term average energy. Combination of the ECC with mel frequency cepstral coefficients (MFCC) delineates the distribution of energy in the time domain and frequency domain, and the features of this group achieve a better recognition effect compared with the feature combination of the short-term average energy, pitch and MFCC. Afterwards, further improvements of ECC are developed. TECC is gained by combining ECC with the teager energy operator, and EFCC is obtained by introducing the instantaneous frequency to the energy. In the experiments, seven status of emotion are selected to be recognized and the highest recognition rate 83.57% is achieved within the classification accuracy of boredom reaching 100%. The numerical results indicate that the proposed features ECC, TECC and EFCC can improve the performance of speech emotion recognition substantially.  相似文献   
253.
In this paper, equivalent surface impedance boundary condition (ESIBC), which takes fractal parameters (D, G) into SIBC, is implemented in the 4-component 2-D compact finite difference frequency domain (2-D CFDFD) method to an- alyze the propagation characteristics of lossy circular waveguide with fractal rough surface based on Weierstrass-Mandelbrot (W-M) function. Fractal parameters’ effects on attenuation constant are presented in the 3 mm lossy circular waveguide, and the attenuation constants of the fi...  相似文献   
254.
MV10 is an MCU which consists of PWM,ADC,CAN and some other function blocks.It is designed for car body's control.Advanced peripheral bus (APB) is a low speed AMBA bus connecting low-power peripherals.This paper presents an implementation of APB interface for MV10 MCU.After that,MV10 can be integrated into any AMBA system on chips (SoCs) easily.We have built a multi-core system with ABMA to verify this design.In this system ARM9 is a main processor mounted on AHB and MV10 acts as a low-power and low-speed slaver on APB.Before building this system,some operations are encapsulated into a task with dedicated ID.MV10 works as a co-processor with ARM by acquiring task ID from ARM.The result of simulation indicates that MCU can work well as expected.Based on our design,MV10 can be mounted on any AMBA system from now on.  相似文献   
255.
The authors have fabricated bottom gate amorphous silicon thin film transistor (a-Si TFT) array using five-step lithography process.The device shows a field effect mobility of 0.43 cm 2 /(V·s),on/off ratio of 7.5×10 6 and threshold voltage of 0.87 V.The instability of a-Si TFT is ascribed to the defect state in the a-Si channel and SiNx/a-Si interface.The present a-Si TFT array with SiN x insulator could be a significant step towards the commercialization of active matrix organic lighting diode (AM-OLED) te...  相似文献   
256.
Applications of platinum complexes as phosphorescent emitters in high efficiency organic light-emitting diodes (OLEDs) were shortly discussed in this paper. Key recent studies on highly efficient blue, green, red and white-phosphorescent OLEDs based on Pt complexes are presented in terms of efficiency and color quality.  相似文献   
257.
Parkinson’s disease (PD) is a heterogenous disease caused by multifactorial etiology. PD is characterized by the loss of dopaminergic (DA) neurons in the substantia nigra and the accumulation of Lewy bodies. In this study, two Drosophila PD models by exposing Drosophila to rotenone (sporadic PD models) are proposed, and the human α-synuclein A30P protein (family PD models) in Drosophila is expressed respectively. Both models recapitulated the main human PD symptoms including the loss of dopaminergic neurons...  相似文献   
258.
It is an important problem that we implement floating point trigonometric functions of high precision with suitable hardware cost for high performance in digit image processing.The coordinate rotational digital computer (CORDIC) arithmetic to is used to solve the above problem in this paper.In order to increase the speed of operation,it chooses the pipeline architecture.The results are disposed by IEEE-754 standard.The CORDIC architecture is modeled by using the verilog HDL and verified with MATLAB program ...  相似文献   
259.
Variable size motion estimation (ME) and disparity estimation (DE) are employed to select the best coding mode for each macroblock (MB) in the current joint multiview video model (JMVM).This technique achieves the highest possible coding efficiency,but it results in extremely large computation complexity which obstructs the multiview video coding (MVC) from practical application.This paper proposes an adaptive early termination of fast mode decision algorithm for MVC.It makes use of the coding information o...  相似文献   
260.
A novel test access mechanism (TAM) architecture with multi test-channel (TC) based on IEEE Standard 1500 is proposed instead of the traditional sub-TAM structure. The cost model of an area-time associated test and the corresponding lower bound of system-on-chip (SoC) test time are established based on this TAM architecture. The model provides a more reliable method to control the SoC scheduling and reduces the complexity in related algorithm research. The result based on the area time associated test cost model has been validated using the ITC’02 test benchmark.  相似文献   
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