Applied Mechanics and Materials Vols. 40-41

Abstract: An indirect approach for distinguishing chaos, surrogate data method, is proposed and applied to analyze non-stationary fault signals in this paper. Firstly, the theory and algorithm of surrogate data method is investigated. And then the correctness and availability in the analysis of the method is tested by three kinds of typical known time series. Finally, we utilize the approach to analyze two groups of non-stationary fault signals from rotor system. The results show that this method is an effective one to identify chaotic characteristic of non-stationary fault signals quantificationally. It can also provide a new way for nonlinear feature etraction and recognition of rotor system typical faults.

Abstract: Life model” is the prediction system chosen for this system. Life model method is a mathematical model of generalized convergence which can predict oil output in macroscopic view. This paper selects several life models such as Weng’s model, Hubbert model and HCZ model; bringing them into the study on the development of the systems for predicting oil output; predicting the oil output of Country M from 2010 to 2050 by this system; and making certain the features of various kinds of mathematical model by applications. The results showed that the system which is based on life model can give an effective prediction on oil output.

Abstract: Based on sustainable energy development strategy，this article has a deep research on the energy policy and the corrective measure from five aspects such as energy demand, consumption, energy supply, energy reserves, energy structure and energy system. The article points out our country should establish the national economic system of energy conservation and the environmental protection，diversified energy supply system，energy reserve system includes of material object reserve, habitat reserve and technological strength. The author also indicate that the energy policy should initiate the energy structure optimization positively. Finally, the article puts forward the policy proposal to our country energy management system, the energy pricing economy, the investment system, the legal framework.

Abstract: In recent years, nanosecond pulse power techniques used in the millimeter-wave solid-state pulse power amplifiers attracted much attention. The rise- and fall-time of the pulse, the flatness of pulse-top and the stability of pulse-to-pulse, which have play important roles in a nanosecond pulse power generator techniques, and directly determine the system performance. In this paper, a method using the outbreak current with low-voltage to drive MOS-FETs is proposed. The measured results show that the rise- and fall-time of the output pulse is less than 1.5 ns with a pure resistance 0.5Ω, and it only needs two 12V power supply to give a output current of 20A with a pulse width of 160 ns at a repetition rate of 540 kHz in continuous mode. A flatness of 3% for the output voltage was obtained,which meet the requirements of ka-band solid-state millimeter-wave pulse power amplifier.

Abstract: A novel millimeter-wave transition from microstrip to rectangular waveguide is introduced in this paper. The theory for this design is explained. The strip conductor on microstrip, which is introduced from the center of a rectangular waveguide broad-wall to its E-plane, is shaped into a triangular loop in the waveguide terminated by a short circuit. A back to back transition operating at Ka band was simulated and fabricated. The experimental results showed the insertion loss of a back to back transition is less than 2.2dB with its return loss greater than 9.1dB from 26.5 GHz to 35.5 GHz.

Abstract: Rice straw and Tiefa coal were used as experimental materials. Under the conditions of different temperatures and Cl/K molar ratio, the experiment was performed by using co-firing devices and ion measure instruments (flame photometer and a visible spectrophotometer). The results reveal that the majority of alkali metals and chlorine are released to gas phase by the precipitation of alkali chloride and HCl(g) above 700°C. Alkali metals release increase with the raising of chlorine content in raw materials. Alkali metals release related to sulfur, silicon and aluminum etc.

Abstract: This paper introduces the Adjacency Matrix at the very beginning, the least transfer between two nodes can be obtained by using the Adjacency Matrix, and then Z matrix is introduced to achieve optimal routing algorithm for public transit transfer and to obtain optimal route by using the “two-step-descending-proliferation” algorithm. Through the "two-step" approach, efficiency and feasibility of data processing was increased. The algorithm focus on multi-objective optimization - takes the least transfer, the least cost, the shortest time, and so on.

Abstract: Phased implementation approach, namely three models: aircraft type distribution model, aircraft scheduling model, robustness model is used to achieve the optimization of aircraft scheduling robustness. Aircraft type distribution model is established to obtain the best model of each leg; then fleet scheduling model is established to determine specified type in the implementation of the specific aircrafts for each flight, flight strings, which meet the constraints, are obtained by solving; finally, the flight robustness model is established, that is, flight string with minimal impact is selected from above flight strings to obtain high robustness of multi-type flight scheduling combination. The phased multi-type aircraft scheduling robust model has been successfully applied in the domestic airline scheduling, it has been achieved a better effect of robust optimization.

Abstract: Pore water pressure and the changes of crustal deformation, fault rupture and seismic activity has important influence. So the pore water pressure and load rock stress – hydro-mechanical coupling mechanism is very important. This paper mainly studies the rock specimens of hydraulic crack damage simulation. This study found: with the increase of the axial compression, sample is on the surface crack. Crack characteristics is smooth and continuously expanding. With the load increasing at the same time, the number of samples is also increased damage elements. The sample was through the cracks. This is due to the effect of water pressure to reduce the size of confining pressure .From the failure mechanism analysis, the distribution of stress non-uniform material will not uniformity, reflected in the actual rock because of the grain and the defects of the random distribution. When the load, the composition of force transmission effect of different deformation and stress in rock, the internal non-uniform stress concentration, local, it will directly cause the weak part, and micro cracks generated change the failure mode of materials.

Abstract: This paper features of IPSec and MPLS technologies, proposes a suitable MPLS VPN security solutions. The program to solve the VPN using MPLS backbone network in the public transport there is a second layer of information can not automatically encrypt, or connect easily made because of errors due to the interruption of information disclosure and other issues. To verify the proposed security program, the actual MPLS VPN can be simplified, abstracestablishing a simulation system MPLS VPN, and using OPNET simulation software simulation, simulation results of VPN officers practical reference value.