Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilize simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilise simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilize simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilise simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilize simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A road marker and related light based warning device are described. The road marker or device includes a thermal sensor that triggers the illumination of at least one light-emitting diode at a predetermined temperature. The temperature may be associated with ice formation. The light-emitting diode(s) may flash to alert motorists to hazardous road conditions. The road marker or device utilise simple components to increase reliability, particularly when the device is subjected to high heat such as when the device is mounted into hot tar seal. The device further includes a switching element that prevents rapid on/off cycling.

Abstract: A key or licence management system for the secure online distribution of digitized audio-visual works (“media”) using encryption techniques. Encrypted media is stored on a media server while the encryption keys are stored on a media key server. Users acquire rights from online retailers to obtain from the media key server keys corresponding to the media they wish to play. The key server encrypts keys before releasing them, preferably with the user's public key using a public key encryption algorithm. Keys are stored in volatile memory at the user's client device and thus the user is in receipt of the key just in time to play the media.

Abstract: A key or licence management system for the secure online distribution of digitized audio-visual works (“media”) using encryption techniques. Encrypted media is stored on a media server while the encryption keys are stored on a media key server. Users acquire rights from online retailers to obtain from the media key server keys corresponding to the media they wish to play. The key server encrypts keys before releasing them, preferably with the user's public key using a public key encryption algorithm. Keys are stored in volatile memory at the user's client device and thus the user is in receipt of the key just in time to play the media.