Applied Mechanics and Materials Vols. 513-517

Abstract: To obtain an adjustable passband filter, one open stub with three branches is loaded on an open loop resonator. The first and the third passband frequencies of the tri-band filter can be flexibly controlled by tuning lengths of three branches, whereas the second passband frequency is fixed. The fabricated filter has good tri-passband performance at 2.19, 4.26, 6.30 GHz. Measured results agree well with the simulated ones.

Abstract: The target system for aerial defense artillery .has been widely used in the shooting training in aerial defense war. Since the performance of the target system has strong influence on the precision of the aerial defense shooting in the training process, the target system has been developed rapidly during the past decade. A novel target system has been proposed in this paper, the shooting principle is also put forward with some innovations and reasonable modification in the design process. In the system design part, the basic performance factors have been brought forward, including some necessary technical indicators and optimized design specification. Through the shooting test under the target system, a perfect performance has been obtained through observer glass experiments. The experiment results have strongly validated the rationalization and the reliability of the designed novel target system for aerial defense artillery.

Abstract: This paper is to assess the impact of ATC automation on controller workload, situation awareness, teamwork and mutual trust, and solve the relationship between human and ATC automation system collaboration. Based on experiment statistics, the method of mathematical statistics has been used to carry on overall analysis, significance analysis and correlation analysis. As a result, in the new generation ATC automation system, the overall level of controllers workload, situation awareness, teamwork and mutual trust is relatively higher than that under traditional condition, along with the increase of the controller work experience, the teamwork consciousness and situation awareness are stronger, the workload is lower, the ATC automation system of mutual trust is higher. Teamwork, workload and mutual trust have a significant positive correlation.

Abstract: The type of atomize-cool and air-cool are widely used in the world now. Air-jet is a very vital instrument in quenching by air-cooling. t is necessary to simulate the inner and outer flow-field of air-jet. By means of computational fluid dynamics soft system Fluent, numerical simulation of quenching air cooling process of air-jet was carried out. The work can support the actual production.

Abstract: There is a problem in normal meander line antenna (MLA) that it is difficult to get performances of miniaturization, high efficiency and high inductance at the same time. A simple novel antenna design for this challenge is described. Two capacitive loads are added at the end of MLA to adjust the impendence. For saving material, holes are digged on the loads. Simulation by HFSS shows that, comparing with the regular MLA, the proposed antennas impedance enhances from 10-12j to 23+150j, and the maximum gain enhances from 1.31dB to 1.67dB, with a read range of 10.1m. Meanwhile the return loss at 915MHz is-34dB, with a wide-10dB bandwidth of 860 ~ 985 MHz.

Abstract: Based on the sub-mini dual ducted UAV dynamics analysis of Newton, and according to the characteristics of the hovering and variable posture mechanism, this paper combined methods of mechanism analysis with system identification to get the attitude model of under actuated sub-mini dual ducted UAV, which contained input variable, output variable and some unknown parameters. Then the subspace method used the real flying data to identify above the attitude model. Finally，the correctness of the identification model was verified.

Abstract: Insulator is a tiny part in electrical equipment, but whether its working condition is safe or not plays a vital role in the safe operation of the entire power system. In this paper, digital image processing technology based on MATLAB is applied, the obtained image of the insulator is processed through filtering, gray-scale processing and binarization processing. The parameters such as insulator's bottom circle area and edge width are extracted, and compared with the calibration parameters to determine the size of insulators. The method to getting more precise characteristic values of insulators is described in this paper. It provides the evidence of judging the working state by comparing with the calibration value to capture measurements of insulators. The digital image processing technology based on MATLAB can effectively monitor the working status, high efficiency and accuracy of the insulator.

Abstract: This paper introduces the power line carrier communication technology and switching power supply, and expounds the factors that affect the switching power supply for power line communication, analyzes how to solve the problem of switching power supply in power line communication, such as analysis of phase noise electromagnetic interference on the impact of switching power supply, and proposes measures to perfect the switching power supply.

Abstract: Automatic vehicle license plate is an important part of intelligent transportation system. The success of the plate recognition will have a deep impact on the construction of intelligent transport systems. Image processing, tilt correction, character delimitation, character recognition and matching are main applications of vehicle license plate recognition, and the above process are implemented in matlab environment. Vehicle license plate location is implemented by vehicle license plate locating method based on edge detection and morphology filter in this article. The tilt correction mode based on Hough transform is used for license plate tilt correction section; character delimitation algorithm is used for character delimitation to achieve the vehicle license plate character segmentation; character recognition method based on template matching is chosen for character recognition section in this article, and successfully identify the license plate number.

Abstract: The reliability of the brake disc is one of the main factors influencing running safety. This paper introduces the causes and harm of train brake disc crack, the application of digital image acquisition technology, and image processing function in MATLAB. We research a method of image preprocessing and subsequent processing by programming language, give effect drawing in each phase, and calculate the pixel size through effective extraction based on the crack characteristics. At last the condition of crack size and actual area is presented. The study can provide a reference for monitoring personnel replace the brake disc timely.