A Study on Piezoresistive Characteristics of Smart Nano Composites based on Carbon Nanotubes for a Novel Pressure Sensor
This paper presents a preliminary study on the pressure sensing characteristics of smart nano composites made of MWCNT (multi-walled carbon nanotube) to develop a novel pressure sensor. We fabricated the composite pressure sensor by using a solution casting process. Made of carbon smart nano composites, the sensor works by means of piezoresistivity under pressure. We built a signal processing system similar to a conventional strain gage system. The sensor voltage outputs during the experiment for the pressure sensor and the resistance changes of the MWCNT as well as the epoxy based on the smart nano composite under static pressure were fairly stable and showed quite consistent responses under lab level tests. We confirmed that the response time characteristics of MWCNT nano composites with epoxy were faster than the MWCNT/EPDM sensor under static loads.
To deal with the market demand and the production organization feature of steel making enterprises,we formulate the optimization of charge design as a cluster analysis problem with quality constraints on chemical compositions.A particle-swarm-optimization-based(PSO-based) solution is proposed for reducing the dimensions based on the principal component analysis(PCA) techniques.The range constraints of chemical compositions for products with similar quality are introduced in terms of traditional process constraints,due time constraints and furnace capacity constraints,etc.The solution adopts an integration schema for charge plan and quality design.It performs the cluster analysis for candidate products with similar chemical compositions and constraints to realize the optimal charge design under quality constraints on steel products of multiple varieties and in small batch demands.