private function _get_Win32_OperatingSystem()
    {
        if ($this->_Win32_OperatingSystem === null) $this->_Win32_OperatingSystem = CommonFunctions::getWMI($this->_wmi, 'Win32_OperatingSystem', array('CodeSet', 'Locale', 'LastBootUpTime', 'LocalDateTime', 'Version', 'ServicePackMajorVersion', 'Caption', 'OSArchitecture', 'TotalVisibleMemorySize', 'FreePhysicalMemory'));
        return $this->_Win32_OperatingSystem;
    }