Applied Mechanics and Materials Vols. 178-181

Abstract: In view of typical many-one distribution network in the modern distribution logistics system, the mathematic model on the inventory-transportation integrated optimization problem with stochastic demand and diversified products was established by using a bi-level programming method. Both decisions of inventory control and transportation arrangement were made at the same time. An improved heuristic algorithm was proposed to divide the integration problem into both problems of the inventory and the transportation: the cost were distributed by the former according to different products and the optimized cost was sought out by the latter according to different periods, thus the inventory-transportation integrated optimization problem was solved through the repeated iteration between the former and the latter. The mathematic description and the heuristic algorithm to the massive practice of the modern distribution logistics system are realized.

Abstract: A fuzzy sliding mode control scheme based on variable rate reaching law for attitude control of flapping wing micro aerial vehicle is proposed in this paper. Based on the feedback linearization technique, a sliding mode controller is designed. To faster response speed, a fuzzy controller is designed to adaptively tune the slope of sliding mode surface. To reduce the chattering, the variable rate reaching law is proposed. The variable rate reaching law is composed of the distance from current point to sliding mode surface in phase plane. The simulation studies for attitude control of a flapping wing micro aerial vehicle have been carried out. Simulation results show that the proposed control scheme is effective.

Abstract: Floating car data (FCD, also called probe vehicle, PV) system is a new and based on a certain percentage of all vehicles in the traffic which are equipped with a location and data communication device transmitting experienced traffic flow parameters to a traffic information center. Then the link travel status can be estimated using these large sample dada. In this paper, an evaluation and analysis method for FCD system in Ningbo was introduced. Firstly, a mathematical statistical method is used to compute the minimum probe vehicles number on one segmental road. Then, the original GPS data was analyzed on several aspects, including PV-GPS data coverage and average probe vehicle number of covered links. Based on the minimum probe vehicles number, we can evaluate overall quality of FCD system and improve it accordingly. Finally, the obtained traffic state information was validated with test drives of independent vehicles driving on a long loop route with many intersections. A valuable conclusion is obtained, and would be a valuable basis for developing FCD system in the further work.

Abstract: Comparing to fuel vehicle, electric vehicle does not apply the heat of the engine as one of the heat resources. Therefore, many heating ideas are proposed to use on Electric vehicle.This paper analyzes the attributes of various heating methods. Heat pump system is the most popular trend of the electric vehicle business, due to the high efficiency. It suggests different heat pump systems, illustrates the trend of future market, and compares the performance of electric vehicle heat pump system using different cryogen.

Abstract: In this paper, the way of setting up the vehicle structural constitutive model is introduceded. With the desert soil three triaxial test data of rock and soil mechanics, the soil structural quantitative parameter ( strain comprehensive structure potential ) is introduced into the soil strength and deformation characteristics analysis.Under the same confining pressure the stress-strain curves of different water content of sand have the same tendency. Through the method of setting up the Duncan-Chang model,structural constitutive model of sand is constructed and the parameters of the model are obtained by testing. The research can provide reference for vehicles and military vehicles to improve crossing through the desert sand.

Abstract: Particle damper comprises granular particle enclosed in a container within a vibrating structure. It may be applied in extreme temperature environments where most conventional dampers would fail. In this paper, the feasibility of an application of particle damping to the noise and vibration control of a drum brake is analyzed. A coupling simulation algorithm based on the discrete element method and finite element method is presented. This method makes it possible to consider parameters of particle damper such as the particle size, ratio and particle material and so on. The validity of this numerical method is examined by a comparison of the experimental results. And the results show that the presented particle damping is effective and the analyses of dynamic feature of a drum brake with particle dampers are reasonable.

Abstract: With the development of heavy haul freight transportation in China, the standard of the limited center height of gravity for car loaded will change heavily. The sharp curve is an unsubstantial part in the rail, reasonably working out the standard must obtain the deeply research of the process of vehicles running on sharp curves. Relying on the experiment and regarding the derailment coefficient and rate of wheel load reduction as the safety assessment standard, study is conducted concerning the safety of C_62BK-wagon loaded running on sharp curves of Beijing-Chengde line, through statistical analysis of experimental data. At last, the safety technical requirements are put forward regarding C_62BK-wagon with gravity center height of 2.4 m running through sharp curves.

Abstract: The study of sound quality which is a newly developed research area has become a hot topic and become to attract increasing attention from academia and industries. The description of sound quality, the technique of subjective and objective evaluation, and the way of improving sound quality inside vehicle are outlined. Based on an extensive discussion over the sound quality issues, the progress in sound quality methodologies and evaluation method are reviewed, and the prospects of the future development are introduced and discussed.

Abstract: With the development of lightweight car，the applications of aluminum alloy wheels are changed extensively. At present, there are many disadvantages in aluminum alloy wheel profession of my country such as the blindness in design, the long period, material consumption, the high cost and so on. In this paper, the CAD as well as the FEA technology is applied. The parametric three-dimensional model of aluminum alloy wheel is constructed using UG software. Taken the former's thickness and the angle between two formers as variables, the wheels with different sizes and shapes are established. Automobile aluminum alloy wheel hub is built and this is helpful to the development of CAE / CAM in the aluminum alloy wheel design.

Abstract: Safety Catch device is the most important mechanism in an elevator. It provides safety protection in case that driving cable of an elevator suddenly breaks. A new type of Safety Catch mechanism with simple structure is provided in this research. When driving device of an elevator failed to function, safety catch device acts automatically, this will prevent elevator cabin from falling down. To compare with conventional ones, this new type safety catch device has the feature of lower impact and simple in structure. In this paper, structure of this new type of safety catch device is detailed; design and related calculation are discussed.