摘要 |
The invention is based on the realization that for a rod-like article, a cigarette for example, having a plurality of ventilation gas flows, the flows can be equated to a single equivalent flow nominally occurring at an "equivalent ventilation point". By establishing one or more flow regimes in a rod-like article and measuring gas pressures, the articles can be monitored for displacement of the equivalent ventilation point, such displacement being indicative of the position of out-of-specification gas flows.
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