56results about How to "Achieve resonance" patented technology

The invention provides a dual-polarized vibrator unit, an antenna and a multi-frequency antenna array. The dual-polarized vibrator unit includes a radiator and a balun support portion for feeding of the radiator. The radiator includes a dielectric substrate, two pairs of dipole antenna arms being disposed on an upper surface of the dielectric substrate and in orthogonal arrangement of plus or minus 45 degrees, and at least one coupling metal strap disposed on a lower surface of the dielectric substrate. Current induction is generated between the dipole antenna arms and the coupling metal strap so that a current path is formed on the coupling metal strap. The vibrator unit and the antenna thereof in the invention can achieve the ultra-broadband, high gain, high efficiency, high cross polarization ratio and high front-ratio, high isolation, low profile and low coupling and is simple and beautiful in structure, easy in engineering realization and suitable for mass production, the production cost is reduced, and the electrical performance index meets the base station antenna industry standard.

The invention relates to a wave power piezoelectric generating device which comprises a wave energy collector and more than one piezoelectric generating units, wherein the piezoelectric generating units are arranged on the wave energy collector; the wave energy collector comprises a U-shaped supporting floating body and a floating body, wherein the opening of the supporting floating body is connected through a rigid connecting rod; a supporting floating body framework is fixedly arranged on the supporting floating body, four support rods are fixedly arranged on the supporting floating body framework, and a generator soleplate, a generator round wall and a generator top plate are sequentially fixedly arranged at the tops of the four support rods through a generator frame; a floating body framework is arranged on the floating body, the floating body framework is rigidly connected with a driving shaft, and the driving shaft sequentially penetrates through the generator soleplate and the generator top plate; support posts sequentially penetrating through the generator soleplate and the generator top plate are fixedly arranged on the floating body framework, and the tops of the support posts are fixedly connected through connecting rods; and each piezoelectric generating unit comprises a plurality of piezoelectric vibrators and scribing sheets, wherein each piezoelectric vibrator comprises a middle layer and two piezoelectric sheets. The invention can realize sympathetic vibration under various incoming wave conditions and obtain higher wave energy conversion efficiency and output electrical energy.

The invention discloses an active resonance C-type buoyancy pendulum wave energy power generation device which is a cabin-shaped wave energy power generation device completely immersed in water. The active resonance C-type buoyancy pendulum wave energy power generation device comprises an energy harvesting system, a power generation system and a raft type base, wherein the energy harvesting systemcomprises a cabin-shaped pendulum body, an automatic mass center adjusting device is arranged in the pendulum body, the pendulum body is fixedly connected to a main shaft, the main shaft is connectedwith the power generation system, the main shaft is further provided with an encoding disc used for testing the swing of the pendulum body, the two side surfaces of the pendulum body are parallel, awave-sheltering surface is of a structure with a larger arc on the upper portion and a smaller arc on the lower portion, wherein the two arcs are concentric, a spiral line, an involute and a high-order curve are adopted for transition between the two arcs, the distance between the outer normal of the transition curve and the axis of the main shaft is the smallest, the wave-facing surface is a plane or an inward-concave arc surface or a curved surface the same as the wave-sheltering surface, the power generation system comprises a chain, a ratchet wheel, a reversing shaft, a speed increaser anda permanent magnet generator, and the power generation system is internally arranged in a pendulum body cabin or located outside the pendulum body. By adjusting the mass center position of the activeresonance C-type buoyancy pendulum wave energy power generation device, real-time resonance between the pendulum body and the wave is realized, and efficient conversion of wave energy is realized.

The invention relates to a power supply system, which. The power supply system comprises a filter, a switch matrix, a resonant network and a rectifier, wherein the filter is connected with an input multi-phase alternating-current power supply; a switch matrix is connected with the multi-phase alternating-current power supply input filtered by using the filter, comprises a plurality of bilateral switch components and used for performing high-frequency processing on the multi-phase alternating current input to finally realize DC (Direct Current) voltage output; the resonant network is connected with the switch matrix and is used for realizing resonance and controlling output current to be sinusoidal current; and the rectifier is connected with the resonant network and is used for rectifying and filtering the sinusoidal current output by the resonant network. Due to the adoption of the technical scheme of the invention, at least two phases of AC (Alternating Current) power supply inputs are converted into direct current; zero-voltage switch-on / off can be realized by using the switch matrix, and zero-current switch-on / off can be realized by using a synchronous rectifying switch in the rectifier; and the efficiency is increased and the consumption of the switching process is reduced greatly.

The invention provides an antenna device and a mobile terminal. The antenna device comprises an antenna body, an antenna feed source and a feed matching circuit, wherein the antenna feed source is connected with a feed point of the antenna body through the feed matching circuit; the antenna body is divided into a first antenna arm and a second antenna arm through the feed point; a first ground point is arranged on the first antenna arm and is grounded through a first tuning circuit; and a second ground point is arranged on the second antenna arm and is grounded through a second tuning circuit.The antenna device provided by the invention can be used as a variety of antennas, so that the number of the antennas which need to be arranged on the mobile terminal can be reduced, thereby reducingthe assembly space occupied by the antennas.

The invention discloses a self-opening velocity type hydraulic energy absorption and consumption device. The self-opening velocity type hydraulic energy absorption and consumption device mainly comprises a steel box girder and a hanging basket, wherein the hanging basket is arranged in a square concave hole at the bottom of the steel box girder; the hanging basket comprises a hanging basket bottom plate and peripheral side walls; the hanging basket bottom plate is provided with a plurality of water through holes; a cover plate is hinged above the water through holes; one rope is connected with each of four corners at the upper part of the hanging basket; after the four ropes are bound together, the four ropes are connected with a hanging rope; the other end of the hanging rope is wound on one side of a rotary barrel; the rotary barrel is fixedly arranged on a top plate of the steel box girder; a pressing device and a friction sheet are mounted above the rotary barrel; a horizontal supporting plate is arranged at each of four corners of the bottom of the square concave hole; a vertical baffle is arranged on each horizontal supporting plate; the vertical baffles are connected with a side plate at the bottom of the square concave hole through limiting springs; and the four corners of the hanging basket bottom plate are supported on the four horizontal supporting plates at the bottom of the square concave hole through round balls. An energy consumption device can be automatically opened when a bridge starts to vibrate, and the vibration of the bridge is inhibited through hydraulic energy consumption.

The invention discloses a preparing method of a reinforced gold nanoparticle cluster fluorescence system based on surface plasma. The preparing method comprises the steps of conducting contact reaction of gold nanoparticle solution and modified gold nanorod solution with buffer solution to prepare the reinforced gold nanoparticle cluster fluorescence system based on surface plasma; among them, modified gold nanorod in the gold nanorod solution comprises gold nanorod, a silicon dioxide layer and an amine modified layer, wherein the silicon dioxide layer is covered outside the gold nanorod, and the amine modified layer is distributed on the outer surface of the silicon dioxide layer; the outer protecting group of the gold nanoparticle in the gold nanoparticle solution is chosen from one kind or multiple kinds of BSA (Bovine Serum Albumin), HAS (human serum albumin) and glutathione. The gold nanoparticle cluster fluorescence system prepared from the method has excellent fluorescence quantum yield.

The invention discloses an antenna of a mobile terminal and the mobile terminal. A metal part is arranged on the surface of the mobile terminal, an S-shaped or U-shaped tuning part is arranged in the antenna, signal feed points of the antenna are distributed close to one side of the mobile terminal, the metal part serves as a part of the antenna and is communicated with the tuning part of the antenna and communicated with the signal feed points of the antenna through the tuning part of the antenna, a ground layer of a circuit board is communicated with the side, away from the tuning part, of the metal part, and the sensitive area of the antenna is tuned to the area away from the periphery of the mobile terminal by the tuning part. According to the antenna comprising the metal decoration part, the signal feed points of the antenna are distributed close to one side, the tuning part is arranged between the signal feed points and the metal decoration part, and in this way, wide-bandwidth coverage requirements of the antenna are met, sensitive points of the antenna are kept away from human hands (human bodies), and good human hand (human body) performance is achieved.

The invention provides a backstepping sliding mode maximum wave energy capture method. The method comprises the following steps: establishing a dynamic model of a direct-drive wave energy power generation device; establishing the mathematical model of a permanent magnet linear generator; designing a maximum wave energy tracking controller based on a backstepping method; and designing a backstepping sliding mode controller through combination of the backstepping method and a sliding mode control method. The structure and the mathematical model of the wave energy capture device and the permanentmagnet linear generator are mainly studied, the optimal power output condition of the system is constructed according to the incident frequency and the amplitude of the wave, the decoupling method ofid=0 is used and the optimal reference current of the d-q axis is obtained. The optimal reference current is controlled and tracked by the sliding mode variable structure. The simulation results showthat the backstepping sliding mode control strategy improves the robustness of the system in comparison with the traditional PID control strategy and is obviously superior to the traditional controlin output current, voltage and power and has obvious advantages in maximum wave energy capture.

The invention discloses a Fabry-Perot cavity and an outer-cavity semiconductor laser, wherein the Fabry-Perot cavity comprises a cavity body, a coupling mirror, a first reflecting mirror and a second reflecting mirror, incident beams are irradiated into the inside of the cavity body through the coupling mirror and rightly irradiated on the first reflecting mirror, after the incident beams are reflected by the first reflecting mirror, the incident beams go back to the coupling mirror and reflecting and transmission happen at the position of the coupling mirror, the beams which are reflected by the coupling mirror are rightly irradiated on the second reflecting mirror, after the beams are reflected by the second reflecting mirror, the beams go back to the coupling mirror, the beams which are reflected by the coupling mirror are rightly reflected on the first reflecting mirror again, and resonance oscillation of the beams among the coupling mirror, the first reflecting mirror and the second reflecting mirror is achieved; transmission beams which are through coupling mirror are irradiated out in the direction which is collinear with and opposite to the direction of the incident beams. Due to the fact that an extra electron feedback system does not need to be controlled when feedback beams are provided by the Fabry-Perot cavity, cost can be reduced, and line width of laser beams is further narrowed in a pressed mode when system stability is guaranteed.

The present invention relates to the technical field of robots, and specifically discloses a robot facial expression realization system comprising a host computer and a lower computer, wherein the upper computer communicates with the lower computer through UART, and the upper computer can send information to the lower computer. Expression command, described lower computer comprises eye screen control board, eye screen display board and power control board, described eye screen control board can resolve the expression command that described upper computer sends into picture group id and picture id, and According to the picture group id and the picture id, the eye screen display panel is controlled to display corresponding emoticon pictures. The robot facial expression realization system of the present invention can quickly establish a good user experience through the expression display based on the chat content and movement instructions, and it is easier to achieve emotional resonance with the user. Robot expression control.

The invention firstly provides a resonance or subresonance destroying method. According to the resonance or subresonance destroying method, variable-frequency load stress waves and fixed-frequency load stress waves are used successively for destroying an object, or two or more kinds of same-frequency load stress wave resonance or subresonance or similar-frequency load stress wave resonance or subresonance are used to destroy an object on the intersecting point of the lines in the propagation direction of the resonance or subresonance. The invention further provides a subresonance power multiplication method. According to the subresonance power multiplication method, the subresonance state of an engine is made to be in the normal working state of the engine, so that the purpose that energy consumption is lowered greatly under the same output power is achieved. The invention further provides a resonance release method. According to the resonance release method, a third path of stress waves is provided for releasing the existing resonance state generated between the two paths of existing stress waves, and the frequency of the provided third path of stress waves is not equal to the frequency of the two paths of existing stress waves. According to the resonance or subresonance destroying method, the subresonance power multiplication method and the resonance release method, the resonance state and the subresonance state generated among the stress waves are fully used, and the purposes of resonance destroying, power multiplication and resonance releasing are achieved.

The invention provides a nonlinear energy trap device with multistable magnetic coupling and a multistable magnetic coupling method. The device comprises a support guide rail, wherein the support guide rail extends in the Y direction and is slidably connected with a support sliding table, a support is fixed on the support sliding table, and an elastic component is arranged on the support; a first linear guide rail and a second linear guide rail extend in the X direction, the first linear guide rail is slidably connected with at least one short guide rail, a short guide rail sliding table is slidably connected to the short guide rail, a magnet assembly is fixed to the short guide rail sliding table and comprises a magnet, a sliding table is slidably connected to the second linear guide rail and connected with the elastic assembly, a magnet vibrator assembly is fixed on the sliding table and comprises a vibrator magnet, and a friction layer making contact with the sliding table is arranged in the second linear guide rail. According to the device and method, the nonlinear restoring force of a spring is coupled with the force of the magnet so that the multistable conditions of monostable, bistable, tristable and more can be realized, and a vibration absorption frequency band is increased.

This invention discloses a loudspeaker system including a sound box, at least two loudspeaker sets in the same performance and composed of one or more than one loudspeakers, each set is installed in the open-end of an independent sound chamber in the box, the chambers are in same shape and size, the adjacent chambers are run-through by a connection tube, and the structure of this invention is favorable to realizing resonance of the loudspeaker sets.

The invention discloses an active resonance C-type buoyancy pendulum wave energy power generation device, which is a cabin-shaped wave energy power generation device completely submerged in water, including an energy capture system, a power generation system and a raft base. Cabin-shaped pendulum body, with an automatic center-of-mass adjustment device installed in the pendulum body, the pendulum body is fixedly connected to the main shaft, the main shaft is connected to the power generation system, and a code disc for testing the swing of the pendulum body is also set on the main shaft, the two sides of the pendulum body are parallel, and the back wave surface is Two concentric circular arcs with a large top and a small bottom. The transition between the two arcs is a helix, an involute or a high-order curve. The distance between the outer normal on the transition curve and the axis of the main axis is the smallest; the wave front is flat or concave. The arc surface or the same curved surface as the back wave surface; the power generation system includes chains, ratchets, reversing shafts, speed increasers, permanent magnet generators, and the power generation system is built in the pendulum cabin or located outside the pendulum. By adjusting the position of the center of mass of the device, the pendulum body can resonate with the wave in real time to realize efficient conversion of wave energy.

The invention relates to the technical field of air conditioning, and in particular to a compressor foot pad, a compressor component, and an air conditioner. The compressor foot pad assembly includesa foot pad main body, one end of the foot pad main body is matched with the compressor main body and the other end of the foot pad main body is matched with a base for supporting the compressor main body, a piezoelectric energy accumulator is installed on the compressor main body and or the base, the heating element is in contact with the foot pad main body and can heat the foot pad main body, wherein the heating element is electrically connected to the piezoelectric energy accumulator, and can obtain the piezoelectric energy accumulator when the compressor body works. The piezoelectric energyaccumulator mounted on the compressor body supplies power to the heating element during working of the compressor body, so that the heating element can heat the foot pad body, so that the foot pad body can be softened, the hardness of the foot pad can be reduced, the hardness can be adjusted, the compressor foot pad assembly can meet the vibration damping requirement in the operation and transportation process, and the vibration damping effect is guaranteed.

The invention discloses a PM2.5 particle removing method. A sweeper scans the frequency of PM2.5 particles in the air and gives a power signal through a detection circuit, the frequency of a power drive frequency-sweeping oscillation circuit is consistent to the PM2.5 particle frequency to form resonance, and small PM2.5 particles are changed into large particles and settle under the gravity effect. The sweeper is connected to a power supply through the detection circuit, the power supply is connected to the frequency-sweeping oscillation circuit, and the frequency-sweeping oscillation circuit is connected to the sweeper. According to the PM2.5 particle removing method, air purification is achieved by scanning the frequency of the PM2.5 particles in the air and utilizing the frequency consistency between an oscillating electric field and the PM2.5 particles to achieve resonance so as to change the PM2.5 particles into the large particles, enable the particles to settle and achieve air purification. The PM2.5 particle removing method is low in energy consumption and good in effect compared with electrostatic dust removal.

A double-frequency four-unit millimeter wave microstrip slot MIMO antenna comprises a rectangular dielectric substrate. Four antenna units with a same structure are arranged on an upper surface of therectangular dielectric substrate, and a metal grounding plate is laid on a lower surface of the rectangular dielectric substrate. Each antenna unit comprises a rectangular metal arm printed on the upper surface of the rectangular dielectric substrate. A short side of the rectangular metal arm is superposed with an edge of the dielectric substrate, a long side of the rectangular metal arm extendsinto the upper surface of the dielectric substrate, a T-shaped structural gap is etched in the metal grounding plate, the T-shaped structural gap is orthogonal to the rectangular metal arm, and a T-shaped head part is close to the edge of the rectangular dielectric substrate. The four antenna units are rotatably and symmetrically arranged at 90 degrees about a center of the upper surface of the rectangular dielectric substrate. By using the microstrip slot antenna structure based on a deformation slot, a millimeter wave antenna design is realized, the microstrip slot millimeter wave antenna can realize resonance at two frequency points, and an isolation degree between antenna ports of each unit is relatively high.

The invention discloses a multi-frequency resonant cavity based on a metal nano-medium column. The multi-frequency resonant cavity comprises 8 metal-medium nano pillars, 4 metal-medium nano pillars inthe 8 metal-medium nano pillars are symmetrically distributed at an inner layer circular region boundary with a periodic radius R1, the other four 4 metal-medium nano pillars are symmetrically distributed at an outer layer circular region boundary with a periodic radius R2, and the length of R1 is smaller than that of R2. The characteristics of metal and medium surface plasma waves are used, theresonance of an external light or electromagnetic signal inside a structural unit through the plasma waves is achieved and is different from resonance caused by a traditional resonant cavity source inan internal part, at the same time, a plasma wave effect is used between the nano pillars to form resonance, thus resonant cavities can be independent of each other and can form a whole body, and a multi-frequency resonant cavity is formed.

The invention provides a parallel direct-driven wave power generation device. The device comprises a moving platform, a fixed platform arranged above the moving platform, and direct-current power generation branch chains of which two ends are respectively connected with the moving platform and the fixed platform through universal mechanisms. At least three groups of the direct-current power generation branch chains are uniformly distributed between the moving platform and the fixed platform. Along with impact of waves, the moving platform receives impact force from different directions and transmits the impact force to one end, connected with the moving platform, of each direct-current power generation branch chain, and the direct-current power generation branch chains are driven to generate power. Based on the design, the moving platform can bear multi-direction wave impact, the multi-direction wave impact can be transmitted to the direct-current power generation branch chains accordingly, and compared with single-degree-of-freedom intermittent power generation in the prior art, the device can achieve multi-dimensional and multi-direction wave energy absorption and conversion.

The invention discloses a multi-band support antenna. The antenna comprises an antenna shell and an antenna mainboard, the surface of the antenna mainboard is fixedly connected with a limiting rubberhead, the surface of the limiting rubber head is provided with a groove, the surface of the groove is sleeved with a metal elastic piece, the left side of the bottom of the inner wall of the antenna shell is fixedly connected with a fixed box, the left side of the inner wall of the fixed box is fixedly connected with a reset spring, the right end of the reset spring is fixedly connected with a sliding plate, the top and the bottom of the sliding plate are slidably connected with the top and the bottom of the inner wall of the fixed box correspondingly, and the middle of the right side of the sliding plate is fixedly connected with a moving block. According to the multi-band support antenna, the antenna mainboard can be placed into a fixed container to work, so that the influence of severeweather elements such as rain, snow, wind and dust outside is avoided, the service life of the multi-band support antenna is greatly prolonged, later rapid maintenance is facilitated, and accurate operation of workers is facilitated.

The invention discloses an automatic vertical condensation dyeing machine for silk by utilizing microwaves. The automatic vertical condensation dyeing machine is characterized in that due to combination of microwave technology and dyeing technology, a magnetron is utilized for microwave oscillation of the dyeing machine such that dye can rapidly dissipate in fabric; a temperature detector and a concentration meter are utilized for transferring temperature and concentration signals to a PLC control system; the PLC control system is used for making corresponding instructions to a controller based on the set temperature and concentration value; the controller is used for correspondingly regulating and controlling the magnetron, a water-cooling circulation system and a rotary disk in order to keep concentration and temperature of the overall dyeing process constant; and while highly-efficient dyeing operation is performed, colors of finished products are guaranteed to be the same due to constant dye concentration.

The invention discloses an active circulator without the need of a bias magnetic field, which is composed of three microstrip feeders, three sets of MIM capacitors, three sets of interdigital capacitors and three sets of microstrip resonant structures, wherein the three microstrip feeders are used for feeding in and out electromagnetic wave signal energy, the three sets of MIM capacitors are respectively connected to the input ends of the microstrip feeders and perpendicular to the feeders, and the three sets of interdigital capacitors are respectively connected to the input ends of the microstrip feeders. The three microstrip feeders are respectively in 120-degree symmetry, the three sets of matched MIM capacitors and interdigital capacitors are in 120-degree symmetry, the three sets of microstrip resonant structures are respectively located in the included angles formed by the three microstrip feeders in a 120-degree symmetry mode. Each microstrip resonant structure is formed by connecting one triangular ring microstrip structure with a power amplifier with a gain of 0dB, and the two sides forming a 120-degree angle of the triangular ring microstrip antenna are parallel to the microstrip feeders. The active circulator has the advantages of no need of a bias magnetic field, convenient integration, high response frequency and the like, and is applicable to a radio frequency microwave communication system.

The invention discloses an acousto-optic induction brain vision device. The acousto-optic induction brain vision device provided by the invention comprises a supporting component, an isolating device and a luminous body; the luminous body is arranged at a first set position of the supporting component; the luminous body comprises a left-eye luminous body and a right-eye luminous body; the brightness change of light emitted by the left-eye luminous body corresponds to the waveform amplitude change of a left ear audio signal; the brightness change of light emitted by the right-eye luminous body corresponds to the waveform amplitude change of a right ear audio signal; the left ear audio signal and the right ear audio signal are binaural beat effect audio signals; and each luminous body is provided with an isolating device used for preventing mutual interference of light between the left-eye luminous body and the right-eye luminous body. According to the invention, the brightness of the light emitted by the luminous body and irradiating eyes changes along with the amplitude change of a brain wave music audio signal; and a binocular beat effect similar to a binaural beat effect is generated in the left and right eye visual channels of a person, so that brain vision is formed, and brain frequency resonance is realized.

The invention relates to an all optical fiber low repetition frequency parametric oscillator used for stimulated Raman scattering. Pump light output by a pump source passes through an isolator and a first optical coupler to enter a parametric oscillation cavity; combined waves of the first and second optical couplers enter a gain optical fiber and a parametric conversion medium; the gain optical fiber amplifies the pump light power of the parametric oscillation cavity entering from the first optical coupler; the output light of the gain optical fiber enters the parametric conversion medium which is in direct fusion with the gain optical fiber; a four-wave mixing effect occurs in the parametric conversion medium; and one part of the output light of the gain optical fiber is directly output,and the other part of the output light of the gain optical fiber returns to the first optical coupler as feedback light, so that the parametric oscillation cavity can be formed. The optical couplersare placed at front of the gain optical fiber so that the gain optical fiber and the parametric conversion medium can be in direct fusion, and therefore, that optical coupler tail fiber generates harmful non-linear effects under low repetition frequency and high peak power pump light can be avoided, parametric conversion efficiency can be enhanced, frequency spectrum noise can be reduced, and theall optical fiber low repetition frequency parametric oscillator can be realized.

The invention provides a harmonic management device for an intermediate frequency furnace. The harmonic management device comprises a controller and at least one filtering circuit which is electrically connected to a three-phase electric power line. The filtering circuit comprises three same filtering branches connected in parallel, wherein each of the filtering branches comprises a filtering reactor which is provided with an adjustment device which adjusts the inductance of the filtering reactor. The controller is used for controlling the adjustment device. Through partly improving the filtering reactor in a traditional LC filtering branch, through changing the working turn number of the filtering winding, the magnitude of the filtering reactor inductance L is changed, the resonance of the LC filtering branches at different frequency points is realized, and the harmonic wave in an intermediate frequency furnace is effectively managed.

The invention discloses a spherical colloidal crystal microcavity and a preparation method thereof. The preparation method of the spherical colloidal crystal microcavity comprises the following steps: first processing one end of an optical fiber into a spherical shape, and then using the spherical part of the optical fiber as a base to self-assemble Methods Colloidal crystals were prepared in spherical parts, and finally the whole optical fiber was chemically etched to obtain spherical colloidal crystal microcavities. The invention uses the spherical part of the optical fiber as a base, adopts a self-assembly method to prepare colloidal crystals on the spherical part, and uses chemical corrosion to completely remove the optical fiber, thereby obtaining a spherical colloidal crystal microcavity. After the light wave is incident into the interior of the spherical colloidal crystal microcavity, it is reflected multiple times by the colloidal crystal structure. At the same time, the photonic bandgap of the colloidal crystal can effectively restrict the light wave in the characteristic band from overflowing the cavity. Therefore, in the photonic bandgap band of the colloidal crystal The light wave can form a whispering gallery mode in the spherical cavity, thereby forming a very high number of oscillations and achieving a very high quality factor.