When there is a positivemeasure on Boole algebra? This problem had more complete results, but they require some set-theoretic hypothesis usually.
布尔代数上何时存在正测度的问题，虽已有相对完整的结果，但多附有一些集论的假设条件。
2
Objectivre: Understanding in recent years c-section rate rise social factor, and takes the positivemeasure to carry on the health education to the pregnant woman, reduces the c-section rate.
目的：了解近年来剖宫产率上升的社会因素，并且采取积极措施对孕产妇进行健康教育，以降低剖宫产率。
3
In the Nun Study and the Mills College research, a measure of early positive expression determined the effect of this positivity over the lifespan.