Abstract:
A method for detecting an arrhythmia hidden by rapid pacing in a rate adaptive pacemaker/defibrillator. Unmasking a potential arrhythmia is accomplished by lengthening the pace cycle length by a small amount for a number of cycles followed by a shortening of the pace cycle length for the same number of cycles giving an average pacing rate equivalent to the desired rate. This can occur at all times or only when conditions make arrhythmia masking possible. Changing the pace cycle by a small amount over a number of cycles will move the arrhythmia and paced rhythm out of synchronization. Forcing the pacer to continue sensing the arrhythmia is accomplished by insuring that the pacer's sense refractory is less than one half of the pacing cycle length. This is done by constraining the programming of that value to one half the minimum pacing cycle length or using an adaptive sense refractory period. In another embodiment, a hidden arrhythmia is detected by periodically checking a relative refractory portion of the pace refractory period to see if a signal indicative of arrhythmia can be detected. This relative refractory period is produced by shortening the established refractory period by a calculated adaptive relative refractory period.
Abstract:
A method for detecting an arrhythmia hidden by rapid pacing in a rate adaptive pacemaker/defibrillator. Unmasking a potential arrhythmia is accomplished by lengthening the pace cycle length by a small amount for a number of cycles followed by a shortening of the pace cycle length for the same number of cycles giving an average pacing rate equivalent to the desired rate. This can occur at all times or only when conditions make arrhythmia masking possible. Changing the pace cycle by a small amount over a number of cycles will move the arrhythmia and paced rhythm out of synchronization. Forcing the pacer to continue sensing the arrhythmia is accomplished by insuring that the pacer's sense refractory is less than one half of the pacing cycle length. This is done by constraining the programming of that value to one half the minimum pacing cycle length or using an adaptive sense refractory period. In another embodiment, a hidden arrhythmia is detected by periodically checking a relative refractory portion of the pace refractory period to see if a signal indicative of arrhythmia can be detected. This relative refractory period is produced by shortening the established refractory period by a calculated adaptive relative refractory period.
Abstract:
A detection-based defense to a wireless network. Elements of the infrastructure, e.g., access points or scanning-only access points, detect intruders by detecting spoofed frames, such as from rogue access points. Access points include a signature, such as a message integrity check, with their management frames in a manner that enables neighboring access points to be able to validate the management frames, and to detect spoofed frames. When a neighboring access point receives a management frame, obtains a key for the access point sending the frame, and validates the management frame using the key.
Abstract:
A detection-based defense to a wireless network. Elements of the infrastructure, e.g., access points or scanning-only access points, detect intruders by detecting spoofed frames, such as from rogue access points. Access points include a signature, such as a message integrity check, with their management frames in a manner that enables neighboring access points to be able to validate the management frames, and to detect spoofed frames. When a neighboring access point receives a management frame, obtains a key for the access point sending the frame, and validates the management frame using the key.
Abstract:
A method and implementation are disclosed for binding a mobile node to a subnet. The invention comprises steps and implementations for intercepting messages sent by a mobile node to a server, associating a predetermined subnet with the intercepted messages and forwarding the intercepted messages to the server. The invention intercepts reply messages sent by at least one server, selects reply messages that are associated with the predetermined subnet. The selected reply messages are forwarded to the mobile node and reply messages that are not associated with the predetermined subnet are discarded.
Abstract:
Methods, apparatuses, and systems directed to reliably providing emergency services to wireless clients. In one embodiment, a wireless client determines if an attempt to transmit an emergency message exists. If so, the wireless client determines if one or more wireless access points support expedited bandwidth capabilities. If so, the wireless client notifies one of the wireless access points that the wireless client has an expedited bandwidth request.
Abstract:
In a wireless LAN (WLAN), methods, apparatuses and systems directed to facilitating configuration of a wireless network is provided. According to one implementation of the present invention, sensors are used to collect data associated with locations and other properties of access points of the wireless network. The collected data can then be used to assist in automatically configuring one or more aspects of the wireless network. In some implementations, the collected data can be used to dynamically re-configure the wireless network in real time. According to another implementation of the present invention, location computation mechanisms are used to collect data associated with the location of one or more wireless clients, and the data is used to dynamically adjust one or more radio frequency (RF) coverage maps in real time. The revised RF coverage maps can then be used to re-configure one or more operational parameters of the wireless network. Implementations of the present invention provide many advantages, such as automating the configuration of the wireless network in real time and facilitating network management decisions.
Abstract:
Wear-detection sensor has a body of electrically insulating material with an opening through which a flowable substance can pass, and one or more electrical conductors surrounding the opening and adapted to undergo a discernable change in conductivity as the insulating material is worn away by the flowable substance.
Abstract:
Wear-detection sensor has a body of electrically insulating material with an opening through which a flowable substance can pass, and one or more electrical conductors surrounding the opening and adapted to undergo a discernable change in conductivity as the insulating material is worn away by the flowable substance.
Abstract:
An ultrasonic sensor is mounted on the splash skirt at the underflow outlet of a hydrocyclone to detect a change in the underflow discharge from the normal conical shape in which the discharge impacts upon the splash skirt to a more cylindrical shape associated with roping.