Abstract: This paper is about the term as used in calculus.The derivative of a function of a real variable measures the sensitivity to change of a quantity (a function or dependent variable) which is determined by another quantity (the independent variable). It is a fundamental tool of calculus. This paper is based on the application of derivative in the field of manufacturing and mathematical modeling
Abstract: The 5% female dummy submarining phenomenon often occur In the C-NCAP two type's frontal collisions,. The submarining not only will cause the serious damage to human body's abdomen, The dummy abnormal movement form will cause body other parts to receive injury. The article introduced the submarining assessment method, carry on the rear seat 5% female dummy localization and experiment deferred to the C-NCAP management rule, through 7 vehicle type's data analyses, carried on the further revelation to the submarining phenomenon.
Abstract: In this paper, the armor steel welds were treated by ultrasonic impact equipment. The stress, hardness and cross section morphologies of the samples under different impact frequencies were measured by electrolytic polishing machines, X-ray stress analyzer and scanning electron microscopy (SEM). The results show that a clear grain refinement layer is formed on the surface of armored steel weld after ultrasonic impact treatment. Its hardness and residual stress all significantly improve. The ultrasonic impact treatment of different frequencies has greatly affect on ultrasonic impact effect, the higher the frequencies are, the better the ultrasonic impact effects are.
Abstract: Apply the test loads of similar truck door on the FE door model of developing truck, analyze the open & close strength with direct transient response method. Based on the strength results, perform fatigue analysis to predict the weak position. Conduct the door open & close test, simulation results and test results match well.
Abstract: By analyzing the inadaptability of vehicle braking system on the long-distance downgrade in the mountainous highway, the paper puts forward the necessity of continuous braking device and pointes out the advantages and disadvantages several continuous braking devices as well as the influencing factors of continuous braking performance, it is concluded that the combination of many continuous brake devices gains access to better continuous braking efficiency.
Abstract: The casting disfigurement on the upper end-face of cast iron roller ring is easy to happen. The paper analyses the method of disfigurement repairing. The disfigurement of centrifugal foundry cast iron roller ring has been eliminated by strict processing technology. Rate of finished products of the cast iron roller ring is improved by repair welding as a result.
Abstract: In this paper, the condition of no quick return peculiarity of crank rocker mechanism is analyzed fist, then the character and design of this mechanism is analyzed. Especially, we developed the methods of smaller quick return’s crank rocker mechanism’s design, and lay the theoretical foundation for the mechanism’s design and application.
Abstract: In order to study the stress of box-girder web under prestressing, and confirming the internal stress distribution of the web, analyzing of vertical prestressed box girder, curved beam prestressed sensitivity under the webs. Establishing finite element model of the box-girder webs vertical prestressing effect is analyzed, results show that the principal tensile stress of the web is sensitive to the vertical prestress, applying the vertical prestress can effectively reduce the principal tensile stress of the web; with the decrease of the effective vertical prestress, the neutral axis above the principal compressive stress decreases rapidly, while below the neutral axis decreases relatively slow; Under the same vertical preloading stress level, the roots of cross section of the compressive stress of web reserves than L/4 section of the web.
Abstract: Hydraulic parts with three sealing devices always leak in use, absorber and air spring for example. Hydraulic cylinder can be sealed by itself if friction hot forming technology is adopted on hydraulic cylinder at both ends. By going through the technology, two sealing devices of hydraulic parts are saved, the leak of hydraulic parts is avoided, the rigidity of hydraulic parts is enhanced, the structure of hydraulic parts is optimized and the service life of hydraulic parts is increased.