Abstract: Example embodiments of systems and methods for data transmission system between transmitting and receiving devices are provided. In an embodiment, each of the transmitting and receiving devices can contain a master key. The transmitting device can generate a diversified key using the master key, protect a counter value and encrypt data prior to transmitting to the receiving device, which can generate the diversified key based on the master key and can decrypt the data and validate the protected counter value using the diversified key.

Abstract: An ultrasonic measurement instrument comprises a housing including a pair of spaced apart legs to define a gap therebetween. Each leg includes an interior cavity. An ultrasonic circuit comprises a transmit circuit for driving a transmit crystal receive in the interior cavity of one of the legs and a receive circuit for receiving signals from a receive crystal in the interior cavity of the other of the legs. A measurement circuit is connected to the ultrasonic circuit to periodically generate pulses in the transmit crystal and to sense pulses from the receive crystal to detect presence of a material in the gap. A self test circuit is operatively associated with the measurement circuit and electrically connected to the ultrasonic circuit for periodically testing operation of the ultrasonic circuit.

Abstract: An ultrasonic point level measurement instrument comprises a measurement circuit and a transducer. The transducer transmits and receives acoustic signals under control of the measurement circuit. An improvement in the transducer comprises a transducer housing including a pair of spaced apart legs to define a gap therebetween. Each leg includes an interior cavity. A pair of crystal assemblies each comprise a crystal mounted to a circuit board. The circuit board includes conduction paths for connection between the crystal and a terminal pad. Each crystal assembly is received in the interior cavity of one of the legs with the circuit board spacing the crystal from walls of the leg. A pair of cables are each connected between the measurement circuit and the terminal pad of one of the crystal assemblies so that the measurement circuit detects presence of a material in the gap.

Abstract: A spill-resistant beverage cup lid which includes a well for adding liquid or powder condiments to a hot beverage and which also serves as a drinking portal is described. The well includes a plurality of apertures in a side wall of the well allowing the condiments to mix with the beverage. In an alternative embodiment, the well further includes a removable flap.

Abstract: A spill-resistant beverage cup lid which includes a well for adding liquid or powder condiments to a hot beverage and which also serves as a drinking portal is described. The well includes a plurality of apertures in a side wall of the well allowing the condiments to mix with the beverage. In an alternative embodiment, the well further includes a removable flap.

Abstract: The jump rope device employs DC motors to rotate two ropes and a dual closed loop control system is used to synchronize the turning movements of the two ropes. An infrared beam is used to monitor the use of the machine by a user. Each motor housing is mounted on a tripod support which can be collapsed for ease of transportation and storage. A floor mat with sensors may be employed for various exercises.

Abstract: The jump rope device employs DC motors to rotate two ropes and a dual closed loop control system is used to synchronize the turning movements of the two ropes. An infrared beam is used to monitor the use of the machine by a user. Each motor housing is mounted on a tripod support which can be collapsed for ease of transportation and storage. A floor mat with sensors may be employed for various exercises.