85 results about "Pulse field" patented technology

A method and system for mapping tissue and producing lesions for the treatment of cardiac arrhythmias in a non-thermal and optimal manner, minimizing the amount of energy required to selectively stun or ablate the target tissues. Energy may be delivered only at the moment(s) of best device position and proximity of an electrode to target tissue, and only during a time in the cardiac cycle determined to be optimal for reversible or irreversible effects. A method may include determining timing of the cardiac cycle and an optimal time within the cardiac cycle for energy delivery, evaluating proximity between at least one energy delivery electrode and the target tissue, and delivering pulsed field energy from the at least one energy delivery electrode to the target tissue when, during the optimal time for energy delivery, the at least one energy delivery electrode is in close proximity with the target tissue.

The invention discloses a strong electromagnetic pulse shielding effectiveness test system which comprises a strong electromagnetic pulse source, a test shielding cavity, a pulse field signal receiving loop and a pulse field signal compensation loop; the strong electromagnetic pulse source generates a strong electromagnetic pulse field in an anechoic chamber, a test window is formed in the side surface of the test shielding cavity, the shielding cavity is arranged in the anechoic chamber, and the side with the test window of the shielding cavity faces the incoming wave direction; each of the pulse field signal receiving loop and the pulse field signal compensation loop comprise receiving antenna / field probes, signal transmission loops and a signal display device; and each receiving antenna / field probe is connected with the signal display device through the first signal transmission loop or the second signal transmission loop. In addition, the invention further discloses a method corresponding to the system. Blanks in the field of strong electromagnetic pulse shielding effectiveness test system and the method are filled. The system is wide in the dynamic range, and a test result isextremely high in accuracy.

A magnetic field transducer includes a phase transition material exhibiting a change from an antiferromagnetic phase to a ferromagnetic phase when heated above a critical temperature, means for applying a magnetic bias field to the phase transition material, and means for heating the phase transition material above the critical temperature. Magnetic recording heads that include the transducer and magnetic disc drives that include the magnetic recording heads are also described. A method of producing a magnetic field pulse including applying a magnetic bias field to a phase transition material, and heating the phase transition material to cause the phase transition material to change from an antiferromagnetic phase to a ferromagnetic phase, is also provided. The phase transition material can comprise a rare earth-transition metal alloy, where the alloy is heated above a compensation temperature.

The invention discloses a quenching detection system and a method which are suitable for being used under a rapidly alternating magnetic field. The system comprises: a quenching detection sensor, a fiber optic isolator, a secondary compensation processing unit and a quenching detector. The quenching detection sensor is connected with the quenching detector through the fiber optic isolator and the secondary compensation processing unit successively. The secondary compensation unit is externally connected with a plurality of current sensors which are installed on an alternating power supply. The quenching detection sensor sends an obtained detection voltage signal to the secondary compensation processing unit after the signal is passed through the fiber optic isolator. The detection voltage signal is accumulated with the detection voltage signal which is sent to the secondary compensation processing unit and is acquired by the current sensors installed on the alternating power supply so as to obtain the effective detection voltage signal. And then the effective detection voltage signal is discriminated by the quenching detector. By using the system and the method of the invention, a large superconducting magnet can perform reliable quenching detection under the condition of rapid changes of working current and the magnetic field.

A method and system for mapping tissue and producing lesions for the treatment of cardiac arrhythmias in a non-thermal and optimal manner, minimizing the amount of energy required to selectively stun or ablate the target tissues. Energy may be delivered only at the moment(s) of best device position and proximity of an electrode to target tissue, and only during a time in the cardiac cycle determined to be optimal for reversible or irreversible effects. A method may include determining timing of the cardiac cycle and an optimal time within the cardiac cycle for energy delivery, evaluating proximity between at least one energy delivery electrode and the target tissue, and delivering pulsed field energy from the at least one energy delivery electrode to the target tissue when, during the optimal time for energy delivery, the at least one energy delivery electrode is in close proximity with the target tissue.

Pulse-generator circuit for generating an input signal for a flip-flop circuit from a clock-pulse signal and a data signal. The circuit includes a control unit for controlling a clock-pulse field effect transistor, a logic field effect transistor and a feedback field effect transistor. To generate the input signal, the control unit is configured in such a way that the clock-pulse field effect transistor is controlled chronologically after the logic field effect transistor and the feedback field effect transistor, thus generating the flip-flop signal.

The invention discloses a nanosecond-level rising edge high voltage pulse generation device in a rydberg state field ionization experiment. The nanosecond-level rising edge high voltage pulse generation device comprises a power supply module, a switch module and an output load circuit, wherein the power supply module is connected with the switch module, and the switch module is connected with the output load circuit. The power supply module comprises a direct current stabilized power supply and an R1C1 filter circuit, and a number I power supply supplies power to the direct current stabilized power supply. The switch module comprises a quick high voltage pulse switch and an external trigger signal source, and a number II power supply supplies power to the quick high voltage pulse switch. The output load circuit is composed of a damping resistor R2, a discharge resistor R3 and a test capacitor C2. The nanosecond-level rising edge high voltage pulse generation device is simple in structure, convenient to operate and good in stability; besides, rising edges are fast, and frequency and the duty ratio can be modulated. In the fields of laser ionization spectroscopy, laser mass-spectrometric technique and the like, a pulse field of nanosecond-level rising edges can be provided for a rydberg state field ionization process, and therefore a high ionization rate can be realized in the rydberg state field ionization process.

A method for extracting shape information for particles with similar shape and corresponding system of a tandem differential mobility analyzer (DMA) and pulse field differential mobility analyzer (PFDMA) system, that executes at least generating a steady state aerosol concentration; passing aerosol flow from the aerosol concentration thru a bipolar charger to produce a known charge distribution; passing aerosol thru a DMA with set sheath and aerosol flows and a set voltage to generate a mono-mobility aerosol; passing mono-mobility aerosol thru a PFDMA system; and measuring mobility as a function of electric field by varying the duty cycle of the pulse in the PFDMA system. Alternatively, the method and system relate to separating particles with different shapes by adjusting the duty cycle of the pulse to reach a higher or lower electric field than in the DMA in which the mono-mobility aerosol was generated; and separating particles based on shape.