One of the signals，other than a distress signal，that can be used by a vessel to attract attention is a(n)（）.
By how much is a signal’s strength reduced when the signal passes through an object thatintroduces 3 dB of attenuation？（）
One of the signals，other than a distress signal，that can be used by a rescue boat to attract attention is a/an（）.
In the absence of a route leading from seaward，the conventional direction of buoyage generally follows（）.
In a pneumatic automation system, a unit producing a signal to govern the position of the controller of the measured variable, relative to the value of the measured variable, is said to have（）.
The directive force of a gyrocompass（）.
In the International Code of signals，a group of three letters indicates（）.
The direction of the southeast trade winds is a result of the（）.
What approximates the signal attenuation of a plasterboard wall？（）
Which of the following operation will have a direct impact on the rate of wear in a cylinder liner （）
A centrifugal impeller consists of a number of vanes curving （） from the direction of rotation.
The most powerful signal of stress is a change of pitch on the vowel.（）
Which of the following commands should be used to open a tty port configured in the /etc/uucp/Devices file as： Direct tty2 - 9600 direct in debug mode， ignoring modem control signal data carrier detect （DCD）？（）
A list signal of one white light indicates that the vessel is （）.
Which of the following components provides a direct source of seawater for the fire main system?（）
Which equipment is the primary source of generating a locating signal?（）
（）is the most visible signal of distress from a lifeboat at sea in the daytime.
When a vessel signals her distress by means of a gun or other explosive signal，the firing should be at intervals of approximately（）.
In the absence of external forces，the center of gravity of a floating vessel is located directly above the（）.
_______ is a figurative technique that directly compares one thing to another by using the signal words as or like.
______is the device that provides amplification(the increase in current, voltage, or power of a signal)without appreciably altering the original signal.
The signal sequence that directs a protein from the cytosol into the nucleus is called nuclear localization signal (NLS).
The first significant role the press played in the United States is that of a signale
Knowing the true cause of the disease, many Christians considered the Black Death a signal of the Last Judgment.()
