Abstract: Filter designing is a work that most electronics engineers often do. In order to avoid editing cumbersome and duplicate MATLAB program every time when design a filter, now we design a filter designing software based on hybrid programming of VC++ and MATLAB. Users only need to enter the performance index; you can get to meet the requirements of the filter amplitude-frequency curve, phase-frequency curve, and the coefficients of the numerator and denominator polynomial of transfer function to achieve the filter design. Engine is implemented by VC++ and MATLAB mixed programming, making the interface friendly and program simple.
Abstract: Based on the author’s research, this article suggests that incorporating national defense factors into the teaching of college P.E. courses is beneficial to raise college students’ awareness of the importance of national defense, can help lay a solid foundation for the building of national defense reserve force and refine and standardize college students’ social behavior as well. It also advances utilizing drills of parade and procession march in order to reinforce and reap the good results from military trainings, improve and enrich the trainings through physical exercises, sports games and extracurricular competitions in which the concept of national defense education should be included and emphasized. In the process of cultural development regarding P.E. systems, a few pieces of advice are offered here to introduce and integrate elements of national defense education.
Abstract: The vibration signals of rotating machinery in operation consist of plenty of information about its running condition, and extraction and identification of fault signals in the process of speed change are necessary for the fault diagnosis of rotating machinery. This paper improves DDAG classification method and proposes a new fault diagnosis model based on support vector machine to solve the problem of restricting the rotating machinery fault intelligent diagnosis due to the lack of fault data samples. The testing results demonstrate that the model has good classification precision and can correctly diagnose faults.
Abstract: In this paper, the new driving structure of three cycloid gears at eccentric angle of 120 with one another is adopted so as to get rid of the weakness for the bearing of rotating arm. Thus, under the condition of that the basic dimension is not changed, by conducting optimization of profile modification and parameters optimization on traditional structure, the axial dimension is increased by width of one cycloid gear transmitting torque is increased about 40%, and the goal of large capacity with small size is realized. Three main forces are stressed upon the cycloid gear in actual work: the meshing force between gear and cycloid gear, the force upon the cycloid gear by the pin of output mechanism and the force upon the cycloid gear by the bearing of rotating arm. The paper mainly aims to work out the force upon the cycloid gear by the pin of output mechanism.
Abstract: The speed reducer with three cycloid gears, namely FA high-precision drive speed reducer, is the most advanced drive device all over the world. The speed reducer has the advantages of small size, little weight, large drive range, long service life, good rigidity, good stability and precision, high efficiency and stable drive. Compared with wave drive by robots, the speed reducer has better fatigue resistance, bigger rigidity, longer service life and higher return difference precision; the FA speed reducer is used more and more frequently in becomes the weakest part of the whole structure. The paper mainly focuses on the study of this structure. When cycloid drive adopts a large drive ratio, in order to avoid the interference of cycloid gears, the size of gears is very small so that the strength of gears is reduced, which becomes the weakness for drive. Therefore, the paper adopts the new structure of horizontal gears. The paper analyzes the force upon cycloid gears of this structure mainly by analysis, the sketch of this new structure of horizontal gears for three-gear cycloid gear.
Abstract: In this paper, we discuss a system of four coupled oscillators with delays. Some sufficient conditions to guarantee the existence of oscillations for the model are obtained. Computer simulations are provided to demonstrate the present results.
Abstract: As a solid solution matrix alloy, nickel-based alloys have the shortcomings that the strength will decrease with increasing temperature. The significance of this experiment is forming the two-phase matrix, in which γ- Ni solid solution are replaced partly by Ni3Al with potential performance at high temperature. In this paper, no visible cracks and pores Ni3Al/γ- Ni composite matrix coatings were prepared on mild steel substrate by laser cladding with mixed powders of two common thermal spying powders of Ni60AAA alloy and Ni-coated Al. The microstructure and phase constitution of the coating were studied through SEM, EDX and x-Ray diffraction analysis technique. The results show the composite coating consists of γ- Ni, Ni3Al, Cr23C6 and CrB, both the main matrix γ- Ni solid solution and the second matrix phase of Ni3Al being free uniformity dendrite and containing some alloying elements such as Fe, Cr, Si, etc,with the dendrites surrounded continuously by the eutectic. It may be possible for improving high-temperature performance.
Abstract: Microcellular foam injection parts have many advantages such as saving material and energy, reducing cycle time, and processing excellent dimensional stability. Despite these advantages, the low surface quality problems limit its application scope seriously. In this study, the microcellular foam injection molding principle and some surface defects were introduced, and the technologies to improve surface quality, such as Gas Counter Pressure (GCP), Rapid Heat Cycle Molding (RHCM), and Film Insulation were summarized in detail. Finally, the prospect of CAE technologies about microcellular foam injection molding was proposed.
Abstract: A type of hydraulic pollutant decontaminating equipment was made in this paper. The decontamination and maintenance means were studied. The circulating decontaminating method was put forward and developed by modularized technique. The hardware of the decontaminating equipment was implemented with single-chip microcomputer and integrated circuit technology. The controlling application program integrated with fuzzy logic and reasoning function was developed. The practical use showed that the decontaminating equipment could be used in the maintenance of hydraulic circuit of bulldozer as well as the other engineering machinery, therefore realizing the quick decontamination and cleaning of hydraulic component and oil on-line purifying.
Abstract: Based on embeded technology a portable fault detection equipment for the construction machinery hydraulic system is developed. The equipment is mainly composed of embeded hardware platform and graphical-interface software platform. The hardware platform includes the core control unit ECM-945GSE industrial computer, 8-channel data acquisition module based on ARM chip, LCD screen, touch screen, power supply module with large-scale operation voltage and wide temperature range, PTT pressure transducers, the integration transducer of temperature, pressure, flow rate transducer as well as equipment chassis. The software system consists of data acquisition procedures, diagnosis, detection and output printing programs and drivers programs. The pilot trial in the armed forces shows that both detectors can be used in repair shop or indoor, but also in the field of construction machinery on-site emergency repair when rapid detection and diagnosis. And it has a strong adaptability.