power with backup, air conditioning, a firewall and likely an intrusion detection system, often backup of your data to one of their machines (but perhaps...

exposure. The most common devices in a reasonable price range usually contain a Geiger-Müller counter. They are suitable for detection of gamma, x-ray, alpha...

two systems used at the sensor to drive autofocus, contrast detection or phase detection. Web search will find many discussions of their relative merits...

foreigner of Chinese descent). See Imperial China for more information on pre-revolutionary China. According to legend, the origin of the Chinese civilization...

permitted to visit from the Hong Kong side. All Chinese citizens may visit from the mainland Chinese side provided they obtain a permit in advance, but...

winds. In some flood-prone areas, local governments have placed flood detection systems to help in evacuation of areas in case a flood is expected. In...

hijackings and bombings. Metal detectors, X-ray machines and explosive detection dogs are all used to make sure that nothing dangerous can be taken aboard...