Multiple logistic regression analyses were used to determine the association between usual number of hours of sleep during a 24-h period and si and SA (past 12 months and lifetime).
Smart protection circuitry is incorporated into the SI-12 to prevent damage to the 12-inch aluminum cone subwoofer if ever over-driven.
内置智能保护电路，能在过载的情况下保护12寸铝锥盘低音单元不受损害。
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Appearing as an ordinary heating vent, the SI-12 is the ideal subwoofer for home theaters, listening rooms or anywhere strong, definitive bass is needed without being seen.