Advanced Materials Research Vols. 433-440

Abstract: This paper proposes a facial expression recognition approach based on the combination of fastICA method and neural network classifiers. First we get some special facial expression regions, including eyebrows, eyes and mouth, in which wavelet transform is done to reduce the dimension. Then the fastICA method is used to extract these three facial features. Finally, BP neural network classifier is adopted to recognize facial expression. Experimental on the JAFFE database results show that the method is effective for both dimension reduction and recognition performance in comparison with traditional PCA and ICA method. We have obtained recognition rates as high as 93.33% in categorizing the facial expressions neutral, anger, or sadness. The best average recognition rate achieves 90.48%.

Abstract: Relaxation-based algorithms are efficient in simulating large-scale circuits. One of the Relaxation-based algorithms, ITA (Iterated Timing Analysis), has even been widely used in industry. Hence we present accelerating techniques to fasten ITA’s speed. The basic idea is to let ITA utilize local time steps of subcircuits as much as possible. Our techniques include a heuristic approach, a method based on Strength of Signal Flow, and the method combining the previous two techniques. Proposed methods are quite advantageous, which have been justified by real experiments.

Abstract: Prestressed anchor cables have been widely used in geotechnical engineering. Correct understanding of prestress loss law is crucial to the design of anchorage supporting, anchorage effects, safety and long-term stability of a whole project. The main focus of this paper is to present a new model and calculation formula for the analysis of prestress loss in soft soils. This model is based on consideration of the coupling effect of anchor cable and soil, and the physical meaning of the two parameters in the formula is investigated, i.e., D1 represents the total amount of prestress loss, the greater value of D1, the less total amount of prestress loss. D2 represents the variation rate of prestress loss of anchor cables, the greater value of D2, the greater variation rate of prestress loss. By applying this prestress loss calculation formula to the analysis of prestress loss law in practice, the analytical results turn out to be nice and accurate. This model explains the prestress loss mechanism in essence and provides a solution to analyze prestress loss characteristics of anchor cables in soft soil area. Meanwhile, the formula can be adopted to forecast the prestress loss of anchor cables at certain time in anchorage engineering in soft soil regions.

Abstract: Signal source output resistance and negative feedback resistance all contribute to restrain transistor non-linearity and improve amplifier linearity. Amplifier sine output voltage and transistor emitting junction non-sine voltage coexist. Transistor emitting junction non-sine voltage is a by-product and doesn’t affect amplifier function. It was proved by experiment and in theory that the input signal magnitude in the basic common-emitter amplifier is not limited with small signal extent condition Ubem≤10mV, and output range is not limited with Ubem≤10mV. It was proved that small signal amplifier conception does not accord with the facts and might be not suitable.

Abstract: Systems as diverse as genetic networks or the World Wide Web are best described as networks with complex topology. A common property of many large networks is that the vertex connectivities follow a scale-free power-law distribution. This feature was found to be a consequence of three generic mechanisms: (i) networks expand continuously by the addition of new vertices, (ii) new vertex with different number edges of weighted selected that connected to different vertices in the system, and (iii) new vertices attach preferentially to sites that are already well connected. A model based on these three ingredients reproduces the observed stationary scale-free distributions, which indicates that the development of large networks is governed by robust self-organizing phenomena that go beyond the particulars of the individual systems.

Abstract: The attendence system uses RFID to realize practicable function for ground operation of coal industry. Each worker is given by a 2.4GHz passive RFID card in order to be recognised by the system. And technologies such as database, internet and microwave communication are combined with B/C structure, which enables the comsumer to manage and operate the system convenietly wherever has the access to the Internet. Also a UDP protocol applied here to make the communication effectivly and works fast. According to the applications among several coal industry enterprises, it indicates the system has the advantages such as user-friendly, fast communication, accurate data transfer, and strong anti-jamming ability etc.

Abstract: The increasing size of wind power generation requires considering wind farm model in power system stability analysis. Nowadays, the most widely used wind turbine type is doubly-fed induction generator, which is concerned here. The wind farm detailed model including every individual DFIG is high-dimensional and costs a lot of computation time, thus wind farm equivalent model is required. This paper presents an eigen analysis based approach to settle wind farm equivalent modeling for power system simulation. Simulation results indicate the equivalent model has good accuracy, and can reflect wind farm features, which is proper for large-scale power system simulation.

Abstract: This paper provides a review of 3D aircraft object recognition methods based on 2D images. First, essentialities and advantages on 3D aircraft image recognition are analyzed. Second, in view of the aircraft image recognition system model, the traits of aircraft images are elaborated, then the methods of aircraft image recognition at every stage are discussed, especial the methods of feature extraction about aircraft image and the feasibilities, which some new methods about 3D object recognition are used to aircraft image recognition, are focused. At last, some issues about aircraft image recognition which should be further studied in the future are proposed.

Abstract: For inertial navigation systems (INS) on moving base, transfer alignment is widely applied to initialize it. Three velocity plus attitude matching methods are compared. And Kalman filter is employed to evaluate the misalignment angle. Simulations under the same conditions show which scheme has excellent performance in precision and rapidness of estimations.

Abstract: This paper presents a new interactive neural network for solving constrained multi-objective optimization problems. The constrained multi-objective optimization problem is reformulated into two constrained single objective optimization problems and two neural networks are designed to obtain the optimal weight and the optimal solution of the two optimization problems respectively. The proposed algorithm has a low computational complexity and is easy to be implemented. Moreover, the proposed algorithm is well applied to the design of digital filters. Computed results illustrate the good performance of the proposed algorithm.