Applied Mechanics and Materials Vols. 513-517

Abstract: The regular indices of the surface water of the Taizi River, Liaoning Province, northeast of China, were investigated. Samples were collected from upstream to downstream locations of the mainstream, and also from the tributaries of the Taizi River in dry season, wet season, and normal season, respectively. The DO values of the surface water ranged from 3.35 mg/L to 18.73 mg/L, 0.09 mg/L to 13.44mg/L, and 3.49 mg/L to 16.9 mg/L, respectively, in the dry season, wet season, and normal season, respectively. The seasonal variations of the pH values of the surface water were in the order of dry season >wet season >normal season.

Abstract: The complicated unsteady flows with moving boundary were simulated numerically by coupling solving unsteady compressible Navier-Stokes equations and 6DOF rigid-body dynamics equations. The Chimera grid technology was used to handle the relative motion. The three-store ripple release of the wing-store configuration was simulated using this method. The computational results are in good agreement with data from other literature, showing that the method used has a strong applicability to complex multi-body separation problem.

Abstract: Aiming at improving the unreasonable situation of flight delay allocation, an optimization model which contains two cases was proposed. One of the cases is to transfer all the delay to several delayed flights to avoid delay spread, which can increase the flight punctuality rate to ensure the departure of the majority flights. Oppositely, the other is to balance the delay losses of airlines, as well as the passengers, for realizing the fairness. According to the latest data from an airport in western China, the model was verified with genetic algorithm, which indicates that the model not only decrease the total delay losses, but also optimize the flight delay allocation which achieves the initial goal.

Abstract: The computability of the solution operator of the Cauchy problem for the nonlinear Davey-Stewartson equation is studied in this paper. Firstly, a nonlinear map K_RH⁵(R²)→C(R;H⁵(R²)), where H⁵(R²) is inhomogeneous Sobolev space on R², defined from the initial value Φ to the solutionu. Then we used the relevant knowledge of type-2 theory of effectivity, functional analysis and Sobolev space to prove that when s>4/7 the solution operator of the Cauchy problem for the nonlinear Davey-Stewartson equation is computable. The conclusion enriches the theories of computability.

Abstract: This thesis studies the splicing and reconstructing problems of regular English paper fragments. By analyzing the feature of information from the same English paper fragments and relying on the gray value matrix of the English character based on the pixel information of complete characters in the document, it establishes a standard model database based on English letters and punctuations. By applying lattice close-degree to make fuzzy recognition of images from two paper fragments and characters from the standard model database, it establishes a matching model of interaction between human and computer to splice and reconstruct English fragments.

Abstract: In this paper, the extended ElGamal public key cryptosystem and digital signature scheme with appendix are described in the setting of the group of units of the ring.Elements of the group of units with the larger order are used as the base elements in the proposed extension instead of primitive roots used in the original scheme. Proposed schemes make periodic change of the group and base elements to provide necessary security level.

Abstract: Clarify the properties of derived design and complement design. The properties of Abstract: The definitions of derived design and complementary design are given. The method of constructing disjoint (13,4,1) design is proposed. The entire procedure of constructing (14,3,1) design ,(26,13,8,4,2) design and (13,9,6) design is also presented completely. 15 disjoint (13,4,1) design , 15 disjoint (13,9,6) design and 7 disjoint (26,13,8,4,2) design are obtained. The number of disjoint (13, 4, 1) design is proved.

Abstract: In order to overcome phase detection algorithm, obtain the accurate phase delay tangent value through improving ranging echo signal calculation module, a real-time difference and low accuracy multi-frequency modulation laser ranging system has designed. Then the corresponding angle can be obtained by the module of the cordic angle calculation, the exact distance can be calculated and combined with the sign bit of output orthogonal I and Q and phase ranging defuzzification algorithm . Noise-signal ratio of the systemic ranging error and echo signal has to do with the word length of calculation module with the SNR=10dB, the word length B=16 bit, phase precision is 0.03 °, distance accuracy is 0.125mm.

Abstract: Design and implementation of a 60GHz millimeter wave communication system for high-speed indoor wireless communication, which is with 1000Mbit/s data rate and for Gigabit WPAN/WLAN. Using the single carrier difference code two-phase shift keying modulation and receiving demodulation technology of 1-bit A/D, to effectively solve the problem of high dynamic range receiver because of the great attenuation caused by the people and objects in millimeter wave band communication channel. To realize the high speed data communication of 1000Mbit/s, dynamic range is more than 50dB when receiving and dispatching antenna angle is 120 °, transmitting power is 1MW and the communication distance is 0.5 to 20m.

Abstract: As the temperature process of beer fermentation has a large time delay, strong coupling and distributed parameter, the process requirements are difficult to satisfy for conventional control. The beer fermentation temperature control model was developed and the Smith compensation and distributed predictive control algorithm were proposed. The simulation shows that the algorithm can satisfy the technological requirements very well.