Applied Mechanics and Materials Vols. 130-134

Abstract: In recent years, Mao and his co-workers developed a class of finite-volume schemes for evolution partial differential equations, see [1-5].The schemes show a super-convergence quality and have good structure-preserving property in long-time numerical simulations. In [6], Chen and Ma developed a scheme which combine the idea of paper [5] and that of the the second-order ENO scheme [7]. In this paper, we propose a scheme which extend the result of [6] and obtain the scheme using the third-order ENO reconstruction. Numerical experiments show that our scheme is robust in long-time behaviors. Numerical solutions are far better than those of [6].

Abstract: In the paper, a plan based on WinCE is proposed to implement the UMTS CC protocol in the circumstance of system restricted by hardware resource. In the plan, we create call connection (CC) thread, which implements state transfer according to primitives. In order to realize the communication of primitives withmessages, the paper applies the way of WinCE message queue, with WinCE memory managing in a dynamic way which can increase the efficiency of memory effectively. In programming, mutex is applied so as to construct and synchronize the threads. Also, function pointer array is used in realizing FSM, which can make programming code more efficient. In the paper, the principle of WinCE is discussed, and also the key code in realization is analyzed. The test proves that the design has the quality of programming efficiently with good real time ability.

Abstract: The principle of color rendering of LCD is discussed. An experiment with EIZO CG 19 LCD and NEC PA 241 LCD was done to test the spectral additive property and the results show that the spectral additivity is held well. A new calculation method based on spectral additivity is proposed and discussed. The proposed method is simple and very few samples need to measure, and the computation precision is very high.

Abstract: A method for nearly orthogonal grid generation is presented in this study. The generating system is based on solution of a system of partial differential equations with finite difference discretization. The influence of the number of grid points, type of boundary, and intensity of the grid quality control function and grid properties are investigated. Specification of both boundary point distribution on all sides and moving boundaries is used. The proposed method is applied to various test problems£¬which shows this method provides a good balance between controlling grid orthogonality and cell aspect ratio.

Abstract: In this paper, both 3-dimentional channel matrix eigenvalue probability distribution and a newly proposed generalized condition number (GCN) are used to analyze the capacity stability of 4-element compact MIMO systems when the mean angle of arrival (AoA) of the incident waves varies in the case that mutual coupling among array elements is considered. Theoretical analysis and numerical simulations show that comparing with the traditional 4-element linear array, 4-element square array with spatially symmetric structure is much less sensitive to the angle of incidence, indicating that the square array can maintain a more stable capacity.

Abstract: To obtain high-quality infrared image real-timely, a new correction enhancement method is proposed. The method can both compensate nonuniformity of IRFPA by using calibration-based piecewise polynomial interpolation correction algorithm and increase image contrast by using histogram-based adaptive threshold image enhancement algorithm. The experiment is performed by carrying out the method in an embedded imaging system. The results show that the system can process infrared image real-timely and the processed image is clear with high signal to noise ratio.

Abstract: The purpose of this paper is to present a 2D depth-averaged model under orthogonal curvilinear coordinates for simulating two-dimensional circular dam-break flows. The proposed model uses an orthogonal curvilinear coordinate system efficiently and accurately to simulate the flow field with irregular boundaries. As for the numerical solution procedure, The SIMPLEC solution procedure has been used for the transformed governing equations in the transformed domain. Practical application of the model is illustrated by an example, which demonstrates that the mathematical model can capture hydraulic discontinuities accurately such as steep fronts, hydraulic jump and drop, etc.

Abstract: Timing-jitter is an important index of timing recovery algorithm. This paper describes impact-factors of timing-jitter in an AWGN channel and discovers that input noise have great influence on it, proposed an improved timing recovery method for adding a loop gain to reduce it. Simulations demonstrate that a timing recovery with loop gain can have performance superior to that of without it, and got the conclusion that add loop gain at the range of 0.1 to 0.3 both timing jitter and timing recovery points can reach minimum values. Better yet, when choose a loop gain at 0.1, timing jitter decrease from ±0.2 to ±0.08, and system’s error rates also have obverse decrease.

Abstract: Spherical cap harmonic (SCH) theory has been widely used to format regional model of fields that can be expressed as the gradient of a scalar potential. The functions of this method consist of trigonometric functions and associated Legendre functions with integral-order but non-integral degree. Evidently, the constructing and computing of Legendre functions are the core content of the spherical cap functions. In this paper,the approximated calculation method of the normalized association Legendre functions with non-integral degree is introduced and an analysis of the entire order of associated non-Legendre function calculation is presented. Besides, we use the Muller method to search out for all intrinsic values. The results showed that the highest order of spherical harmonic function for constructing regional model of fields is limited, thus high-resolution spherical harmonic structure of local gravity field need to be improved.

Abstract: With the dramatically increase of the scale of the Network Processor, traditionally verification method can't satisfied the requirement of market due to the limitation of the simulate speed. For solving the verification problems, a novel hardware accelerate simulator for Network Processor based on FPGA is proposed. This simulator improves the simulate speed remarkably. Furthermore, the probed signals of the Network Processor can be dumped into wave file real-timely.