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Traditional CAD software uses mesh-based representation , but recent developments in software are exploring the use of volumetric object representation to generate surfaces , and in at least one case , the use of implicit modeling via the definition of fields that then generate cellular structures .
 enabling technology: CAD; concept or principle: software; concept or principle: surfaces; enabling technology: modeling; engineering feature: cellular structures
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 enabling technology: CAD; concept or principle: software; concept or principle: surfaces; enabling technology: modeling; engineering feature: cellular structures