Abstract: A computer-implemented method of determining backoff windows in a wireless computer network is disclosed. The method comprises defining, by an access point in the wireless computer network, a plurality of collision patterns related to message transmission via one or more communication channels in the wireless computer network; detecting, by the access point, occurrence of one of the plurality of collision patterns involving a group of sender nodes in the wireless computer network that have each transmitted a message to the access point and received no acknowledgement message from the access point indicating successful transmission; setting to a first length a length of a backoff window for avoiding collision in data transmission based on a size of the group of sender nodes; sending a first message to a first plurality of nodes in the wireless computer network, the first message instructing performance of backoff during the backoff window having the first length.

Abstract: A network device stores in its nonvolatile memory, in response to detecting a power outage in a tree-based network, an identifier for a preferred parent and a distance identifier for the network device within the network. In response to power restoration, the network device starts a trickle timer based on the ring identifier, for determining whether a beacon request from a transmitting node and destined for the preferred parent is detected during the waiting interval. In response to the network device detecting the beacon request during the waiting interval, the network device sets its channel hopping schedule to the corresponding channel hopping schedule of the transmitting node in response to determining the beacon request is destined for the preferred parent, enabling rejoining with the preferred parent in response to detecting a beacon from the preferred parent to the transmitting node via the corresponding channel hopping schedule of the transmitting node.

Abstract: A computer-implemented method of determining backoff windows in a wireless computer network is disclosed. The method comprises defining, by an access point in the wireless computer network, a plurality of collision patterns related to message transmission via one or more communication channels in the wireless computer network; detecting, by the access point, occurrence of one of the plurality of collision patterns involving a group of sender nodes in the wireless computer network that have each transmitted a message to the access point and received no acknowledgement message from the access point indicating successful transmission; setting to a first length a length of a backoff window for avoiding collision in data transmission based on a size of the group of sender nodes; sending a first message to a first plurality of nodes in the wireless computer network, the first message instructing performance of backoff during the backoff window having the first length.

Abstract: An apparatus includes a sub with recesses along an exterior wall to receive inserts, an antenna case including a coil surrounded by a sacrificial wear portion of a material through which signals between the coil and a formation of interest may pass. An eroded outer wall of the sacrificial wear portion is restorable by application of an uncured restorative material to the antenna case. A method includes securing an antenna case having a coil there within onto a sub, surrounding the coil with a metal sleeve shield, and radially receiving and securing a multi-piece sacrificial wear member intermediate the antenna case and a retainer ring having a threaded bore. The multi-piece sacrificial wear member is replaceable after use by unthreading the retainer ring to release the sacrificial wear member for radial removal from the sub.

Abstract: A system and apparatus for configuring a well logging assembly having an elongate sub with a bore therethrough, a leading end connection and a trailing end connection, a plurality of sets of recesses in an exterior wall of the sub to receive a plurality of sets of inserts, each having a threaded exterior surface, a plurality of internally threaded retainer rings, and a plurality of well logging devices securable to the exterior wall of the sub using the retainer rings to threadably engage the inserts received in the recesses. The system enables convenient configuration and reconfiguration of the well logging assembly by enabling convenient securing of a first well logging instrument to the sub at a variety of spacings from a second well logging instrument to provide a variety of depths of investigation into a geologic formation penetrated by a drill string containing the well logging assembly.

Abstract: A system and apparatus for configuring a well logging assembly having an elongate sub with a bore therethrough, a leading end connection and a trailing end connection, a plurality of sets of recesses in an exterior wall of the sub to receive a plurality of sets of inserts, each having a threaded exterior surface, a plurality of internally threaded retainer rings, and a plurality of well logging devices securable to the exterior wall of the sub using the retainer rings to threadably engage the inserts received in the recesses. The system enables convenient configuration and reconfiguration of the well logging assembly by enabling convenient securing of a first well logging instrument to the sub at a variety of spacings from a second well logging instrument to provide a variety of depths of investigation into a geologic formation penetrated by a drill string containing the well logging assembly.

Abstract: An apparatus includes a sub with recesses along an exterior wall to receive inserts, an antenna case including a coil surrounded by a sacrificial wear portion of a material through which signals between the coil and a formation of interest may pass. An eroded outer wall of the sacrificial wear portion is restorable by application of an uncured restorative material to the antenna case. A method includes securing an antenna case having a coil there within onto a sub, surrounding the coil with a metal sleeve shield, and radially receiving and securing a multi-piece sacrificial wear member intermediate the antenna case and a retainer ring having a threaded bore. The multi-piece sacrificial wear member is replaceable after use by unthreading the retainer ring to release the sacrificial wear member for radial removal from the sub.

Abstract: A system and apparatus for configuring a well logging assembly having an elongate sub with a bore therethrough, a leading end connection and a trailing end connection, a plurality of sets of recesses in an exterior wall of the sub to receive a plurality of sets of inserts, each having a threaded exterior surface, a plurality of internally threaded retainer rings, and a plurality of well logging devices securable to the exterior wall of the sub using the retainer rings to threadably engage the inserts received in the recesses. The system enables convenient configuration and reconfiguration of the well logging assembly by enabling convenient securing of a first well logging instrument to the sub at a variety of spacings from a second well logging instrument to provide a variety of depths of investigation into a geologic formation penetrated by a drill string containing the well logging assembly.

Abstract: An apparatus includes a sub with recesses along an exterior wall to receive inserts, an antennae case including a coil surrounded by a sacrificial wear portion of a material through which signals between the coil and a formation of interest may pass. An eroded outer wall of the sacrificial wear portion is restorable by application of an uncured restorative material to the antennae case. A method includes securing an antennae case having a coil there within onto a sub, surrounding the coil with a metal sleeve shield, and radially receiving and securing a multi-piece sacrificial wear member intermediate the antennae case and a retainer ring having a threaded bore. The multi-piece sacrificial wear member is replaceable after use by unthreading the retainer ring to release the sacrificial wear member for radial removal from the sub.

Abstract: An apparatus includes a sub with recesses along an exterior wall to receive inserts, an antennae case including a coil surrounded by a sacrificial wear portion of a material through which signals between the coil and a formation of interest may pass. An eroded outer wall of the sacrificial wear portion is restorable by application of an uncured restorative material to the antennae case. A method includes securing an antennae case having a coil there within onto a sub, surrounding the coil with a metal sleeve shield, and radially receiving and securing a multi-piece sacrificial wear member intermediate the antennae case and a retainer ring having a threaded bore. The multi-piece sacrificial wear member is replaceable after use by unthreading the retainer ring to release the sacrificial wear member for radial removal from the sub.

Abstract: A system and apparatus for configuring a well logging assembly having an elongate sub with a bore therethrough, a leading end connection and a trailing end connection, a plurality of sets of recesses in an exterior wall of the sub to receive a plurality of sets of inserts, each having a threaded exterior surface, a plurality of internally threaded retainer rings, and a plurality of well logging devices securable to the exterior wall of the sub using the retainer rings to threadably engage the inserts received in the recesses. The system enables convenient configuration and reconfiguration of the well logging assembly by enabling convenient securing of a first well logging instrument to the sub at a variety of spacings from a second well logging instrument to provide a variety of depths of investigation into a geologic formation penetrated by a drill string containing the well logging assembly.