Research on locating control method of ball mill based on prediction
To solve the difficulty of precise locating of large inertia ball mill, a new method based on prediction is put forward. The feasibility of this method was analyzed using the motor theory and analysis on the ball mill kinematics and dynamics. The equipment to install rotary encoder that was connected to the ball mill was designed. And the testing hard ware based on single-chip microcomputer was build, and data of the angle and the rotational speed of the ball mill were acquired. With the tool of Mat lab, data were analyzed. The results shows that the angle predicted from the starting stage is very much closed to the angle which is measured, and the tolerance is very small, and it can meet the application completely.
Research on precise locating control of large inertia ball mill
To solve the problem of difficulty in precise locating of batch ball mill, the kinetic model was build, and parameters relationship between starting and shutting down were analyzed, control system was designed. At the stage of starting of ball mill, load torque, rotary inertia and so on could be acquired. Based on the relationship of ball mill kinetic parameters between starting and shutting off, parameters at the stage of shutting off could be predicted. With these parameters, the angle that the ball mill would roll after power off could be predicted. With the angle, the optimum spot to cut off power of ball mill could be find, and precise locating and stopping of ball mill could be implemented. The control system is simple in structure, easy for installation and suitable for the reconstruction of existing ball mills control.
Diversity of Electrospinning Approach for Vascular Implants: Multilayered Tubular Scaffolds
Abstract The biomimetics of biological structures found in nature remains one of the most promising approaches to engineer functional tissues from natural or synthetic biocompatible materials for the replacement of damaged or injured parts of the human body. Recently, medical therapeutic regimes have advanced into a new era, overcoming the known mechanical and biological variances that occur when using autologous or synthetic grafts. Basically, the core concept of tissue biofabrication, commonly referred to as tissue engineering, is to find out the favorable cellular microenvironments to grow a living tissue prior to clinical uses. In fact, the ability of stem cells to regenerate is controlled via signaling pathways (growth factors) and supporting materials (scaffolds) that guide the cellular activities. After the first successful experiments to fabricate polymer fibers from their solutions, Cooley proposed the use of an electric field a century ago (Cooley (US 692:631, 1902 ). The electrospinning technique has been continually developed as a fruitful polymer processing technique to draw ultrafine nonwoven fibers. Electrospun polymer fibers have been used for a wide range of technical and biotechnical applications such as filtration, organic solar cells, tissue engineering, and drug releasing implants. In this regard, this review begins with an overview about the various spinning approaches for the fabrication of polymer fibers as well as the basic principles of electrospinning process. In addition, this review will highlight vascular bypass surgery and, in particular, the needs for vascular tissue engineering. Finally, the review includes some of the latest attempts to improve the mechanical and biological properties of electrospun polymeric fibers and summarizes the challenges and prospects for the future. Lay Summary However, vascular defects are treated successfully via bypass surgical bypass grafting using autologous or synthetic vessels. The small-diameter vessels (less than 6) are often associated with high failure rate. This review reports some of the recent features that should be highlighted to fabricate an ideal graft for small-diameter vascular grafts. The review introduces multilayered conduits as an alternative approach to overcome the known mechanical and biological mismatches of single layered vascular grafts of electrospun polymers.