Abstract: An air conditioning system can be toggled between a heating mode, in which heat is withdrawn from a source (e.g., a geothermal source) and deposited into a conditioned space (e.g., a building), and a cooling mode, in which heat is withdrawn from the conditioned space and deposited into the source. The air conditioning system uses a combination of efficiency-enhancing technologies, including injection of superheated vapor into the system's compressor from an economizer circuit, adjustable compressor speed, the use of one or coaxial heat exchangers and the use of electronic expansion valves that are continuously adjustable from a fully closed to various open positions. A controller may be used to control the system for optimal performance in both the heating and cooling modes, such as by disabling the economizer circuit and vapor injection when the system is in the cooling mode.

Abstract: A valve arrangement for controlling gas flow. A gas block includes a gas inlet, a gas outlet, and a gas cavity fluidly connecting the gas inlet to the gas outlet. A diaphragm is configured for controlling gas flow between the gas inlet and the gas outlet. An actuator is configured to vary the position of the diaphragm so as to control the gas flow. The actuator comprises a tubular housing; a plunger positioned inside the housing and having an actuating extension extending outside of the housing and coupled to the diaphragm, the plunger configured to be slidable inside the housing; a piezoelectric body positioned inside the plunger; and a pre-loader applying force to the plunger so as to press the plunger against the piezoelectric body.

Abstract: A valve arrangement for controlling gas flow. A gas block includes a gas inlet, a gas outlet, and a gas cavity fluidly connecting the gas inlet to the gas outlet. A diaphragm is configured for controlling gas flow between the gas inlet and the gas outlet. An actuator is configured to vary the position of the diaphragm so as to control the gas flow. The actuator comprises a tubular housing; a plunger positioned inside the housing and having an actuating extension extending outside of the housing and coupled to the diaphragm, the plunger configured to be slidable inside the housing; a piezoelectric body positioned inside the plunger; and a pre-loader applying force to the plunger so as to press the plunger against the piezoelectric body.

Abstract: Disclosed is a system and method for a rapid deployment beacon that may be hand-held. A rapidly deployable untethered beacon device will gain elevation while transmitting an emergency, or other, beacon and location signal is enabled to clear obstructions such as terrain and buildings in order to extend the communications range of said beacon.

Abstract: Disclosed is a system and method for a rapid deployment beacon that may be hand-held. A rapidly deployable untethered beacon device will gain elevation while transmitting an emergency, or other, beacon and location signal is enabled to clear obstructions such as terrain and buildings in order to extend the communications range of said beacon.

Abstract: Techniques for determining whether a lead related condition exists based on a correlation between a parameter indicative of impedance of a lead and a parameter indicative of motion of the lead. In some examples, the techniques include generating an electrical signal that is indicative of impedance of the lead, generating an electrical signal that is indicative of motion of the lead, and monitoring the frequency, amplitude, and phase of the electrical signals in order to identify a correlation. In some examples, if a lead related condition is identified, an alert is provided or a sensing or therapy modification is suggested.

Abstract: Techniques for determining whether a lead related condition exists based on a correlation between a parameter indicative of impedance of a lead and a parameter indicative of motion of the lead. In some examples, the techniques include generating an electrical signal that is indicative of impedance of the lead, generating an electrical signal that is indicative of motion of the lead, and monitoring the frequency, amplitude, and phase of the electrical signals in order to identify a correlation. In some examples, if a lead related condition is identified, an alert is provided or a sensing or therapy modification is suggested.

Abstract: Systems and methods are provided that estimate when to replace a medical device that is implanted in a patient due to battery depletion. These systems and methods significantly reduce the need for service calls made to medical device manufacturers that relate to battery longevity. In some examples, these systems and methods estimate a battery end of life based, at least in part, on an actual battery voltage received on an actual transmission date and a model transmission date determined based on the actual battery voltage. The estimated battery end of life is further based on a comparison of the model transmission date with the actual transmission date.

Abstract: Systems, methods and devices are provided for automatically detecting and classifying power-on-reset (POR) events occurring in medical devices. Data regarding the operating parameters of the medical device is communicated to a remote server where a POR detection algorithm is operated to detect whether a POR event occurred in the medical device. Upon detection of a POR event, the remote server determines a severity rating of the POR event, a basis of the POR event, and/or the time of the POR event, where this information is associated with the POR event itself. An automated alert message is then generated and communicated to at least one of a patient, a clinician, a care giver or another device with the information about the POR event.

Abstract: Systems and methods are provided that estimate when to replace a medical device that is implanted in a patient due to batter deplection. These systems and methods significantly reduce the need for service calls made to medical device manufacturers that relate to battery longevity.

Abstract: A gas delivery system accurately measures and optionally regulates mass flow rate in real time. A fluid conduit connects an inlet valve, calibration volume, flow restrictor, and outlet valve in series. Pressure and temperature sensors are coupled to the calibration volume. One or more pressure sensors may be attached across the flow restrictor. Alternatively, an absolute pressure sensor may be attached upstream of the flow restrictor. One embodiment of differential pressure sensors comprises a floating reference differential pressure sensor, including a first transducer attached to the fluid conduit upstream of the flow restrictor and a second transducer attached to the conduit downstream of the flow restrictor. In this embodiment, each transducer receives a reference pressure from a reference source, and optionally, after the calibration volume is charged, the floating reference differential pressure transducers are calibrated.

Abstract: A gas delivery system accurately measures and optionally regulates mass flow rate in real time. A fluid conduit connects an inlet valve, calibration volume, flow restrictor, and outlet valve in series. Pressure and temperature sensors are coupled to the calibration volume. One or more pressure sensors may be attached across the flow restrictor. Alternatively, an absolute pressure sensor may be attached upstream of the flow restrictor. One embodiment of differential pressure sensors comprises a floating reference differential pressure sensor, including a first transducer attached to the fluid conduit upstream of the flow restrictor and a second transducer attached to the conduit downstream of the flow restrictor. In this embodiment, each transducer receives a reference pressure from a reference source, and optionally, after the calibration volume is charged, the floating reference differential pressure transducers are calibrated.

Abstract: An apparatus and method control the pressure in a system by continuously measuring the pressure and comparing it to a desired set pressure. The apparatus and method record a history of the measured pressure as a function of time and calculate the rates at which the pressure changes. The rates at which the pressure changes are recorded and the rate at which the rates change is also calculated to determine the rate at which the apparatus and method can vary the rate of change of pressure. The apparatus and method calculate the amount of time required to reach the desired set pressure and compare it to the amount of time required for the rate of change of the pressure to become zero and adjust the flow of a gas in the system so that the desired set pressure is achieved at substantially the same time as the rate of pressure change becomes zero.

Abstract: A track servoing system is disclosed which is particularly useful with floppy disk memories. The system improves the positioning accuracy of a read/write head during a reading operation through the use of tunnel erase heads as read heads. The tunnel erase heads are positioned on either side of the read/write head and their outputs are differentially measured to provide direction and magnitude information to servo positioning electronics. The invention is particularly reliable in reading eccentric variations in data tracks caused by environment, i.e., humidity, temperature, etc.