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Based on the elastic theory of liquid crystal and variation theory,the capacitance characteristics of the strong anchoring hybrid alignment nematic(HAN) liquid crystal cell is studied considering the flexoelectricity of liquid crystal.Through numerical simulation using the Matlab software,the induced capacitance-voltage curves for different flexoelectric coefficients are obtained.With the increase of the applied voltage,the capacitance increases linearly for e11+e33≥0;however,for e11+e330,the capacitance begins to decreases and then increases with increasing the applied voltage.And,with the increase of absolute value of the flexoelectric coefficients,the influence of flexoelectric effect on the capacitance will be also enlarged.

Objective: To clarify whether the acupoints of Zusanli (ST36) and Sanyinjiao (SP6) have specific actions other than non-acupoints to bone.Methods: Forty Sprague-Dawley female rats were divided into five groups: Sham operated (sham) group; Ovariectomized (OVX, model) group; non-acupuncture group; OVX, needling on Zusanli and Sanyinjiao (Acp-A) group; OVX, needling on the reverse sides of Zusanli and Sanyinjiao (Acp-B) group; OVX, periostineal stimulation on the same height as points of Zusanli and Sanyinjiao (Acp-C) group. The experiment was continued for 23 weeks and then all animals were sacrificied.Results: OVX had a significantly higher body weight and lower bone mineral density (BMD) on the lumbar vertebrae, total femora and tibiae than sham rats, however, Acp-A showed a higher BMD compared with the other OVX groups. On the other hand, bone weights, bone strength and bone morphometry such as trabecular volume, trabecular separation, labeled width and bone formation rate also showed the same improvements in Acp-A as compared to the other OVX rats.Conclusion: The stimulation on Zusanli and Sanyinjiao specifically prevented the development of osteopenic rats compared with non-acupoints.

The few-mode fiber can be used to transmit limited orthogonal modes, which has the advantages of small modular interference and easily controlled modes. The Brillouin scattering sensor based on the few-mode fiber can effectively reduce the cross sensitivity of multi parameter measurement, and realize the measurement of multi physical quantity. In this paper, based on the wave optics theory, the Brillouin scattering spectrum parameters of the step-index few-mode fiber are analyzed, such as frequency shift, line width and peak gain and so on. Firstly, the transmission modes of the few-mode fiber are analyzed. The finite element analysis result shows that there are 5 kinds of transmission modes:LP01, LP11, LP21, LP02 and LP31, and their effective refractive indexes are 1.4664, 1.4652, 1.4637, 1.4630 and 1.4616, respectively. Secondly, the mathematical models of the Brillouin frequency shift, line width and peak gain of different modes in the few-mode fiber are analyzed. Finally, the parameters of Brillouin scattering spectrum with different modes' superposition are also discussed. In the few-mode fiber, due to the different effective refractive index, the light of each mode is propagated along its respective path and interacts with the particles in the fiber, thus producing different Brillouin scattering spectrum. The simulation results show that the frequency shift of the Brillouin scattering spectrum of each mode is in a range of 10.19-10.23 GHz, and the frequency shift increases with the decrease of the mode order. The Brillouin line width of each mode is in a range of 32-34 MHz, and the line width also increaseswith the decrease of the mode order. Moreover, the relative amplitude of the Brillouin scattering gain spectrum increases with the decrease of the mode order. The mathematical models of this paper are used respectively to analyze the Brillouin scattering spectra of other types of step-index few-mode fibers. It is shown that the Brillouin frequency shift, Brillouin line width and peak gain of other types of step-index few-mode fibers also increase with the decrease of the mode order. In a step-index few-mode fiber, intramodal Brillouin scattering spectrum and the intermodal Brillouin scattering spectrum are both in line with the distribution of Lorenz curve. However, the intermodal Brillouin scattering spectrum of modes' superposition leads to the line width broadening of the Brillouin scattering spectrum, and the relative amplitude of the intermodal Brillouin scattering spectrum of modes' superposition being generally smaller than that of intramodal.

In China, land consolidation represents different features and contents in various social system, and land consolidation with modern sense began in the 90’s of 20th century. In the meantime, land consolidation program is set up in the land resources management specialty in universities. The teaching and practice of land consolidation program has become the key point of land resources management research and reform. Combining with the features and contents of land consolidation during the present period, this thesis illustrates the construction of teaching system, the layout of teaching content and the design of teaching approach of land consolidation program, including the basic theory of teaching, land consolidation project, land consolidation design, item budgetary estimation, practical teaching, the design of teaching methods of land consolidation program etc.. Meanwhile, in order to intensify the learning effect of land consolidation program, this thesis also discusses the significance of constructing Industry-University-Research cooperation mode and propounds the IUR mode of university, government and industry.

This article designs an auto measurement and control system of the aircraft data recorder based on optical fiber transmission, this system can remote real-time monitor 5Km outside of the aircraft data recorder and read the data afterward. Data link transmission of the system uses 1B/12B encoding and decoding method in order to achieve DC-balance, which can guarantee that the remote command and data are correct. The whole system is not only the unique evaluation tool in design, production and experiment of the aircraft data recorder, but also the key to obtain the entire flight test data.

Isolation between antennas is one of the most important indexes for electromagnetic compatibility (EMC) problem on airborne platform. Take the Rooivalk helicopter for example, as the electrically size of the airborne platform is large, the structure is complex, the simulation results are usually not accurate enough. Due to the inaccuracy of the former modeling method which used the simple typical geometric to replace the real helicopter model, the professional software ICEMCFD/AI⋆Environment (AIE) is employed to restore the helicopter model. Based on the obtaining of the accurate helicopter model, the MLFMA method and Combined Field Integral Equation (CFIE) are employed to analyze the isolation between three VHF antennas mounted on the Rooivalk helicopter. Both accuracy and computing speed are considered, the results have some guidance significance to the optimization of the antenna layout and the EMC preliminary design on airborne platform.

The article introduced the structure and technology method of the auto test system based on PXI bus, for the core equipment of the aircraft telemetry system, requiring high work reliability. The article detailed the key technology about PCM decoding, data recording and real-time display. The validation of the final technology index was realized by computer making real time analysis and post analysis to the data. At present, the system was validated adequately in actual project application; it will be to enhance test efficiency of the corresponding domain.

The article introduced the structure and technology method of the auto test system based on PXI bus, for the core equipment of the aircraft telemetry system, requiring high work reliability. The article detailed the key technology about PCM decoding, data recording and real-time display. The validation of the final technology index was realized by computer making real time analysis and post analysis to the data. At present, the system was validated adequately in actual project application; it will be to enhance test efficiency of the corresponding domain.

An optimal design approach which combines the real frequency method and the direct numerical optimization is used to design a broadband matching network for an electrically small antenna. According to the characteristic of electrically small antenna, a network topology which improves the electrically small antennapsilas efficiency observably is designed with two methods respectively, and the design result is computed and validated with simulation software. Finally, the two methods are compared in the paper. Results show that the VSWR of the antenna is below 2.5 and its efficiency is above 30% in the pass band by optimal design, that is, the performance of the antenna is improved by a wide margin.

In this paper, a hybrid genetic algorithm has been successfully applied to broadband matching network design for antennas. Genetic algorithm (GA) and simulated annealing (SA) have been combined to enhance the search efficiency, which can avoid both the slow convergence of GA and the dependence on the initial parameters of SA. Considering the impedance bandwidth and power available from the source delivered to the load, GA based on the parallel selection algorithm is used. The broadband matching network over the band 225 to 400 MHz has been designed based on this improved hybrid genetic algorithm. The results show that the broadband matching network has broad impedance bandwidth and high covering power. The improved hybrid GA is an effective method of the broadband antenna matching network design.

Sometimes we will search varieties of resources in the network, yet it is difficult to meet some special demands properly by using general searching-engine. P2P network is an effective method of sharing and searching resources. We have proposed a model of P2P-based resource network (PBRN), through analyzing the basic architecture and resource sharing property of P2P network. PBRN is a distributed, virtual, dynamic and loose pure P2P network and it is composed by resource entity freely. And we have analyzed its application on educational information and resources with real examples.

Horizontal correlation is one of the most important characteristic parameters in ocean acoustics. In a shallow water acoustic experiment, we observed that the transverse correlation coefficient is an oscillation function of frequency. A model based on adiabatic normal mode theory in a random inhomogeneous waveguide which is statistically isotropic in a horizontal plane is developed. The theory indicates that the oscillation of the transverse correlation coefficient is mainly due to the normal mode interference.