रात्रिभागौ द्वौ स्वप्नकाला त्रिभागः संवेशनोत्थानिकः ॥ कZ_०२.३१.०७ ॥
rātribhāgau dvau svapna-kālā tribhāgaḥ saṃveśana-utthānikaḥ
夜の二つの区分は睡眠に充て、第三の区分は就寝の整えと起床(夜間の処置・警戒管理)に充てる。
It implies planned night supervision—checks, repositioning, readiness to respond to disturbances—rather than leaving valuable assets unattended.