Dynamic Analysis and Control of the Clutch Filling Process in Clutch-to-Clutch Transmissions

Clutch fill control in clutch-to-clutch transmissions influences shift quality considerably. An oncoming clutch should be applied synchronously with the release of an offgoing clutch to shift gear smoothly; therefore, the gap between the piston and clutch plates should be eliminated when the torque capacity is near zero at the end of the clutch fill phase. Open-loop control is typically implemented for the clutch fill because of the cost of pressure sensor. Low control precision causes underfill or overfill to occur, deteriorating shift quality. In this paper, a mathematical model of an electrohydraulic clutch shift control system is presented. Special dynamic characteristic parameters for optimal clutch fill control are subsequently proposed. An automatic method for predicting initial fill control parameters is proposed to eliminate distinct discrepancies among transmissions caused by manufacturing or assembling errors. To prevent underfill and overfill, a fuzzy adaptive control method is proposed, in which clutch fill control parameters are adjusted self-adaptively and continually. Road vehicle test results proved that applying the fuzzy adaptive method ensures the consistency of shift quality even after the transmission’s status is changed

Self-assembly of 3D fennel-like Co3O4 with thirty-six surfaces for high performance supercapacitor

Three-dimensional (3D) fennel-like cobalt oxide (II,III) (Co3O4) particles with thirty-six surfaces on nickel foams were prepared via a simple hydrothermal synthesis method and its growth process was also researched. The crystalline structure and morphology were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. The Brunauer-Emmett Teller (BET) analysis revealed that 3D fennel-like Co3O4 particles have high specific surface area. Therefore, the special structure with thirty-six surfaces indicates the good electrochemical performance of the micron-nanometer material as electrode material for supercapacitors. The cyclic voltammetry (CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopy (EIS) were conducted to evaluate the electrochemical performances. Compared with other morphological materials of the similar sizes, the Co3O4 particles on nickel foam exhibit a high specific capacitance of 384.375 F.g(-1) at the current density of 3A.g(-1) and excellent cycling stability of a capacitance retention of 96.54% after 1500 galvanostatic charge-discharge cycles in 6M potassium hydroxide (KOH) electrolyte

Study on vibration characteristics and tooth profile modification of a plus planetary gear set

The governing vibration differential equation of a plus planetary gear set has derived from the Lagrange method. Its three often neglected components are considered: [1] the meshing damping, [2] the elastic bearing support of the sun wheel, [3] and the angles between the movement direction of the planet carrier and the gear meshing line. A simulation model for a plus planetary gear set is built. The influence that the key components have on vibration characteristics is analyzed. Model validation is performed by comparing the theoretical, simulated and measured natural frequencies. In order to reduce vibration and noise, a comprehensive finite element model of a plus planetary gear set is built. It provides useful information on dynamic transmission errors of the plus planetary gear set. The tooth profile modification is optimized by using the genetic algorithm. The optimal tooth profile modification is validated by the results of the experiment

Investigation of the Impact of Surrounding Light on Monitor’ Color Showing

AbstractUnder surrounding light, the color showing on monitor's surface is produced by its emitting light and the reflected part of surrounding light by the surface. Utilizing the color characterizing relation of monitor, the actual color showing performances of two monitors in color gamuts and tone curves under different conditions of surrounding light were investigated. The experiment results showed that the luminance values of some dark colors and black point could increase with the illuminance increase of surrounding light, resulting in the compress in gamut within the color space area. And the same phenomena appeared in every color tone curves. But the change in lightness value of the white point was much smaller relatively. And the results revealed simultaneously that the compress extent could not only correlate directly with the illuminance of surrounding light, but also with the relative increase in black point lightness, further, with the intrinsic emitting light and reflecting capability of the screen surface

Cultural Industrialization: A Value Realizing Path for Industrial Heritage

In accordance with the definitions in and out of China and current status of exploitation and utilization of industrial heritage, values of industrial heritage can be summarized as historical, artistic, scientific and economic values. Succession, transmission and innovation of these values through careful plain and scientific management of cultural industries not only coincide with the trend of industrial integration, reflecting the new requirement of the development in cultural industries, and but also serve as communication platform for interactive development of industrial heritage and cultural industries. The paths of cultural industrialization for realizing values of industrial heritage consists of tourist economic model, conference and exhibition model, art and creative economic assembling model, and urban cultural remodeling.Key words: Industrial heritage; Cultural Industrialization; Mode