By means of analyzing principles of spindle drive of high speed winding machine for synthetic filament, four kinds of practical mathematical models of spindle drive are discussed in view of definition of linear density of synthetic filament, winding mass, measurement of actual rotating speed of contact roller and spindle as well as synthesis. At same time, control methods of computer control system are provided. Theoretical supports and effective measures are provided for putting into effect quickly in production process and ensure constant velocity winding. It is an important technology for high speed winding machine.

Existing medical masks have various disadvantages, such as the environmental damage caused by disposable masks, the discomfort and poor ventilation caused by prolonged mask wearing, and the lack of aesthetic design in mass-produced masks. Thus, this study used quality function deployment, the fuzzy analytic hierarchy process, and fuzzy comprehensive evaluation to research, develop, and design masks. The aforementioned methods were also used to determine the ranking of design requirements. The following priority ranking of design requirements from most to least important was obtained: reducing discomfort at the contact between the mask and the skin (0.265), avoiding foul odor inside the mask (0.187), convenient cleaning and portability (0.166), good airtightness (0.152), suitable aesthetic design for wearing in public and on social occasions (0.130), and reducing waste (0.100). Experts evaluated mask designs, and their opinions were subject to fuzzy analysis. Specifically, 50% of the experts evaluated the designs to be “good” or “very good”. Only 29% of the experts rated the design results as “average”. Thus, the innovative mask designed in this study can meet the needs of users, overcome the drawbacks of existing masks, and provide a feasible solution for the current COVID-19 pandemic.

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