The phrase "a concealed threat" is correct and usable in written English.
It can be used to describe a situation where a threat is not openly expressed but is implied or hidden.
Example: "The politician's speech contained a concealed threat against his opponents, suggesting dire consequences for those who opposed him."
Alternatives: "an implicit threat" or "a hidden threat".
Neuroscientist Vince Clark of the University of New Mexico, Albuquerque, for example, has found that applying 2 milliamps of current to a person's scalp for just 30 minutes can double the speed at which they learn a game in which players must detect a concealed "threat," such as a bomb or sniper, in a video clip.
In a radio interview Friday, Intelligence Minister Yuval Steinitz said Kerry's tone "carried a concealed threat that Israel would be punished if we do not reach an agreement".
Compared with high-resolution screening imaging, the concealed threat detection in range profiles can observe a large area and requires a short time.
However, it is difficult to derive a definite distribution model to represent the practical clutter in concealed threat detection, which may consist of radar echoes of the human body, clothing, the ground, and thermal noise.
Even though the Roses were always the bigger band, Happy Mondays were arguably more original, with their louche, category-shrugging soup of dance beats, psychedelia and barely concealed threat.
For most people, the concealed threats — an explosive device hidden behind an oil drum; the shadow of a sniper's rifle protruding over a rooftop — can be identified only with training and practice.
"The image produced is a black and white, ghost-like outline of an individual's body without any distinguishing features such as hair or facial features, making it impossible to recognise people but simple to detect concealed threats".The machines should provide a less intrusive, more effective, but probably slower way to check passengers.
Meanwhile, terahertz radar can also detect concealed threats in range profiles (the real range profile of a metallic pistol model beneath clothing is obtained by 0.34 THz radar, as shown in Fig. 1).
Fig. 1 Real high-resolution range profile of a metallic pistol model beneath clothing Fig. 2 Diagram of monitoring of concealed threats.
"They have by far the most developed ability to detect concealed threats," she said.
The machine takes X-ray photographs of passengers, and can reveal concealed threats without requiring the removal of clothing.
