Abstract: Techniques are disclosed relating to securely authenticating communicating devices. In various embodiments, a computing device receives, via a network connection with a network, a first certificate for a first public key pair of the computing device. The computing device provides the first certificate to an offline accessory device and receives a second certificate for a second public key pair maintained by the offline accessory device. The computing device performs a verification of the second certificate and, responsive to the verification being successful, interacts with the offline accessory device. In some embodiments, prior to providing the first certificate, the computing device determines an ordering in which the first and second certificates are to be exchanged by the first computing device and the offline accessory device, and the first certificate is provided to the offline accessory device in accordance with the determined ordering.

Abstract: Techniques are disclosed relating to securely authenticating communicating devices. In various embodiments, a computing device receives, via a network connection with a network, a first certificate for a first public key pair of the computing device. The computing device provides the first certificate to an offline accessory device and receives a second certificate for a second public key pair maintained by the offline accessory device. The computing device performs a verification of the second certificate and, responsive to the verification being successful, interacts with the offline accessory device. In some embodiments, prior to providing the first certificate, the computing device determines an ordering in which the first and second certificates are to be exchanged by the first computing device and the offline accessory device, and the first certificate is provided to the offline accessory device in accordance with the determined ordering.

Abstract: In some implementations, the device may include exiting a shelf-life mode and turning on a peer-to-peer wireless protocol in response to detecting a power source. A device identifier can be provided to a host device via the peer-to-peer wireless protocol. A connection ticket authorizing the electronic device to connect to a wide area network can be received from the host device via the peer-to-peer wireless protocol. The connection ticket can be being generated by a server system using a private key. The connection ticket may include the device identifier associated with the electronic device. A connection to a wide area network can be requested from an access point using a network wireless protocol. A software update can be performed over the wide area network via the access point.

Abstract: A wireless power transmitting device includes a surface adapted to support a container containing a wireless power receiving device and further includes a wireless power transfer coil positioned to couple with a wireless power receiving coil of the wireless power receiving device when the container is placed on the surface. The wireless power transmitting device detects a presence of the wireless power receiving device when the container containing the wireless power receiving device is placed on the surface and determines whether the wireless power receiving device permits wireless power transfer while it is inside the container. Using the wireless power transfer coil, the wireless power transmitting device wirelessly transmits power to the wireless power receiving device through the container to charge a battery of the wireless power receiving device, in accordance with determining the wireless power receiving device permits wireless power transfer while it is inside the container.

Abstract: Techniques are disclosed relating to securely authenticating communicating devices. In various embodiments, a computing device receives, via a network connection with a network, a first certificate for a first public key pair of the computing device. The computing device provides the first certificate to an offline accessory device and receives a second certificate for a second public key pair maintained by the offline accessory device. The computing device performs a verification of the second certificate and, responsive to the verification being successful, interacts with the offline accessory device. In some embodiments, prior to providing the first certificate, the computing device determines an ordering in which the first and second certificates are to be exchanged by the first computing device and the offline accessory device, and the first certificate is provided to the offline accessory device in accordance with the determined ordering.

Abstract: A method of playing chess for two, three or four persons, the game comprises a playing board having a checkerboard array of rows of squares. Four additional playing areas are contiguous with the four sides of the checkerboard and conventional chess pieces are staged in conventional layout within the additional playing areas. Each set of chess pieces including distinguishing characteristics, such as color, for differentiation. The pawns initially move forward as in conventional chess, however, to provide for additional chess strategy the pawns may change to a second direction of forward movement by capturing an opponent on the side of the second direction on any space on the game board. The pawn may then continue to move forward in this second direction, which is a 90.degree. change in direction. Each pawn can be provided with a mechanism for indicating which direction the pawn can move and attack. The game is played conventionally except as modified as described above.

Abstract: Apparatus to indicate the temperature of an X-ray tube target includes an analog storage circuit to simulate the heat energy stored. Input signals representing the current and the voltage of the electron beam in the tube are multiplied to give a signal representing the instantaneous power input. The power signal is integrated in the storage circuit to give a temperature signal representing the total heat input. The temperature signal is dissipated by a cooling curve circuit representing the heat loss with time. An indicator reads the temperature signal.Input voltage and current signals are processed to refer them to ground before multiplication. The current signal is corrected to set its zero value. The voltage signal derived from a transformer primary is corrected for transformer regulation. To eliminate spurious inputs the power signal is gated to the storage circuit only when a measured current is flowing.

Abstract: Failure inducive operating conditions of an X-ray generator tube are sensed. Some of the sensed operating conditions are events such as hot overload of the target and thermal shock of the target, while other sensed operating conditions include hot target bearing use and thermionic cathode filament heater use. Certain of the sensed operating conditions are integrated, with the integrated output being compared against a predetermined standard to yield a prediction of remaining operating life. Other sensed conditions, if present, are indicative of incipient failure without integration. The integrated signals are stored in electrochemical cells and read out periodically for a prediction of incipient tube failure.