Final answer:
Concealment is usually detected by various technologies like gamma ray, x-ray, neutron-scanning devices, and metal detectors, which are used by customs officers and military personnel for security purposes.
Step-by-step explanation:
Concealment is usually detected by a variety of methods depending on the context. For instance, customs officers might use gamma ray, x-ray, or neutron-scanning devices to inspect trucks and cars and reveal concealed items. Such technologies are crucial at ports of entry, helping enforce regulations against the introduction of invasive species or contraband.
Metal detectors are another common tool used by military personnel to locate hidden weapons and explosives. The aforementioned technologies, including upgraded security gates at airports, use advanced detection capabilities. It's important to note that the presence of an observer can affect the natural behavior of individuals, which is why detection methods should be as inconspicuous as possible to avoid altering the subjects' behavior.
The effectiveness of these detection methods is not only based on the technology itself but also on the training of the personnel, such as trained sniffer dogs, and the existence of policies that impose strict penalties for those caught violating the regulations.