Abstract: Disclosed herein is a portable thermoelectric device including a thermoelectric cooler; a probe configured to measure a temperature inside the device; a compartment fan configured to circulate air in the device, the air having been cooled by a cold side of the thermoelectric cooler; an exhaust fan at least partially positioned in the device and in communication with an external environment, such that the exhaust fan is configured to vent heat from a hot side to the external environment; and a power source configured to receive a range of input voltages. In some embodiments, a first input voltage results in a first temperature differential between an internal environment in the device and the external environment and a second input voltage results in a second temperature differential between the internal environment and the external environment.

Abstract: Peer-to-peer communication is established between two remote computing units over a network channel, even though a permanent network address is not known. An originating computer sends a message over a monitor channel, such as a circuit-switched telephone line, to a receiving computer creating a triggering event. In response to the triggering event, either the originating computer or the receiving computer determines a network address associated with either the originating computer or the receiving computer. Then, using the network address, peer-to-peer communication between the originating computer and receiving computer is established over the network channel.

Abstract: Peer-to-peer communication is established between two remote computing units over a network channel, even though a permanent network address is not known. An originating computer sends a message over a monitor channel, such as a circuit-switched telephone line, to a receiving computer creating a triggering event. In response to the triggering event, either the originating computer or the receiving computer determines a network address associated with either the originating computer or the receiving computer. Then, using the network address, peer-to-peer communication between the originating computer and receiving computer is established over the network channel.

Abstract: An electronic coin acceptor is described which generally comprises a synthesizer for generating a driving signal having a selectively variable characteristic, a computer for controlling the selectively variable characteristic of the driving signal such that at least one predetermined testing characteristic for each coin denomination to be tested for acceptability is selected for the driving signal in a predetermined sequence, an inductive filter for creating an electromagnetic field in response to the driving signal and for producing an alternating signal which is responsive to an electrically conductive object in the presence of the electromagnetic field, a comparator for detecting when the alternating signal crosses a predetermined threshold level and for producing a level detect signal indicative of the threshold crossing, and the computer including a counter for determining whether a conductive object in the presence of the electromagnetic field is an acceptable coin from the level detect signal.